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UU\4 , Cornell University Library The original of tiiis book is in tine Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924030750180 THE THEORY AND PRACTICE OF Military Hygiene BY EDWARD L. MUNSON, A.M., M.D. Captain, Medical Department, United States Army ILLUSTRATED BY EIGHT PLATES AND NEARLY FOUR HUNDRED ENGRAVINGS NEW YORK WILLIAM WOOD AND COMPANY MDCCCCI K ^((i> ioi ■%^rns-Gs^ O^QH^lWr^^ Copts Bit WILLIAM WOOD AND COMPANY PUBLISHERS' PRINTING COMPANY ■82-34 LAFAYETTE PLACE, NEW YORK BRIGADIER-GENERAL GEORGE M. STERNBERG Surgeon- General, United States Army WHOSE PROFESSIONAL LABORS HAVE SO MATEKIALLY CONTBIBUTED TO THE ADVANCEMENT OP SANITARY SCIENCE, AND WHOSE OFFICIAL ADMINISTRA- TION HAS SO GREATLY PROMOTED THE WELFARE OF THE ARMY AND THE EFFICIENCY OF THE MEDICAL DEPARTMENT "Cbis Booft IS RESPECTFULLY DEDICATED BY THE AUTHOR IN GRATEFUL APPRECIATION OF MANY ACTS OF KINDNESS PREFACE, For the preparation of a work on the subject of military hygiene, the author has no apologies to offer. Save a small collection of sanitary pre- cepts, intended for the use of officers of the line, no book exclusively devoted to the preservation of the health of troops has been published in the English language in more than a generation. The more complete works on general hygiene contain much material which has no applicabil- ity to the military service, and, on the other hand, they leave unnoticed a large number of subjects a knowledge of which is of the highest impor- tance to the military sanitarian. For these reasons, many of the lessons learned by bitter experience in camp and garrison, diniug a period in which sanitary science has made its greatest progress, have been practically lost to medical officers of the present day, and the experience of the past few years has demonstrated the need of a text-book dealing directly with the sanitary problems peculiar to the military service. This it has been the endeavor of the author to supply in the present volume, which it is hoped will be found available not only as a book of reference for medical officers, in connection with their sanitary duties, but also as a practical guide to officers of the line, with respect to the care of troops over whom they have control. In view of the fact that this book is in- tended for use under conditions in which recourse to a library of reference will rarely be practicable, it has been thought best not to increase the size of an already large volume by including a bibliographical index of the authorities, some twenty-seven hundred in number, referred to in the text or CQnsulted in its preparation. A list of these authorities has, however, been preserved, and may be placed at the disposal of those who desire to go more fuUy into the vast subject of military hygiene. In conclusion, the author desires to express his great indebtedness to Colonel Charles Smart, Assistant Surgeon-General, United States Army, at whose suggestion and through whose kindness the preparation of this work was undertaken, and whose encouragement and assistance rendered its com- pletion possible. Possessed of an infinite knowledge of sanitary affairs, it is the misfortune of the military service that pressure of public business made it necessary for him to delegate the writing of this book to a less worthy pen. The author has received much valuable aid from his wife in the prepar- ation of notes and of the index. E. L. M. Washington Barracks, D. C, January 1st, 1901. CONTENTS. CHAPTER I. PAGK The Selection of the Recruit 1 General considerations — Defectives — Nativity of recruits for the United States army — Previous status of recruits — Age — Heiglit — Weiglit — Chest measure- ments — Average proportions of the recruit — Examination of the recruit — Gen- eral qualifications for military service — Causes for rejection in the recruit — Mental infirmities — Moral infirmities — Constitutional disqualifications — The skin — The head — The spine— The ears — The eyes — The face — The mouth and fauces — The neck — The chest — The abdomen — The genito-urinary organs — Af- fections common to both upper and lower extremities — The upper extremities — The lower extremities — Re-enlistments — Proportion of rejections — Causes of rejection. CHAPTEE II. The Development of the Rbckuit 33 I. General considerations of physical training — The untrained recruit — Determi- nation of physical deficiencies in the recruit — Exercise in relation to muscular development and power — Exercise as affecting the nervous system — Influence of exercise upon the heart — ^Exercise in relation to the chest and lungs — E^^- cise as affecting the kidneys — Weight as affected by exercise — Exercise as af- fecting the functions — General results of systematic exercise — Exercise as influ- encing the occurrence of disease — Government of exercise — Division of exercise — Training — Exhaustion — Over-training — Proper physical proportions — Devel- opment of special parts — General plan for physical development — Physical training in foreign services — Physical training in the United States service — Schools of instruction. II. Consideration of special exercises — Attention — Manual of arms — Setting-up exercises — Fencing — Bayonet exercise — Target practice — Practice marches — Rimning drill — Equitation — Natation— Gymnasium exercise — Applied gym- nastics — Guard duty — Other exercises — Athletic sports. III. Mental and moral education. CHAPTER III. The March in Campaign, . . . 74 General considerations of the march — The march step — Work done on the march — Position of troops on the march — Time — Rapidity — Length — Meteoro- logical conditions — Terrain — Equipment — Forced marches — Night marches — Delays — Rests — Use of fluids — Straggling — Convalescents — Mental occupation — Accidents of the march — Blisters and excoriations — Pied forc4 — Heart strain —Health of troops. viii CONTENTS. CHAPTEE IV. PAGE Water, 94; I. Quantity — Permanency of supply — Rain-water — Surface-waters — Ground- water — Search for water — Transportation of water. II. Relation of drinking-water to disease— Quality as inferred from physical ex- amination — Color — Clearness — Lustre — Taste— Odor — Other considerations — Chemical analysis of water — The water-sample^ — Total solids — Hardness — Chlorine — Organic material — Nitrites — Nitrates — Ammonia — Oxygen-consum- ing capacity — Dissolved oxygen — Lead and copper — Microscopical examina- tion of water— Bacteriological examination of water. III. Purification of drinking-water — Purification by physical means — Purification by mechanical means — Improvised filters — Maignen filters — Berkefeld filters — Pasteur-Chamberland filters — Purification by chemical means. CHAPTEE V. The Ration, .... 155 I. General considerations of food — Relation of food to the work of the soldier — Requirements of the soldier's dietary and ration — Quantity of United States army ration — Quality of ration — Variety in ration — Wastage of ration — Savings from ration — Additions to ration — Cooking of ration— Means of cooking the ration — Meals — Service of ration— General messes — Foraging — Billeting — Req- uisitions as a means of supply. II. Subsistence and messing in foreign armies. III. The several articles of the ration — Meat and fish components — Fresh meat — Meat contracts— Military abattoirs — Beef — ^Beef -cattle — Weight— Age — Condi- tion — Health — Dressed beef — Age — Sex — Quality — Cysticercus disease — Tuber- culosis — Anthrax — Actinomycosis — Other diseases — Mutton — Pork — Pork measles — Trichinosis — Bacon — Salt-pork ■ — Horse-meat — Slaughter-houses — Preservation of meat — Method of slaughter — Refrigerated and frozen meat — Preservation by heat — Desiccation — Smoking — Canning — Salting — Chemical preservatives — The cooking of meat — Boiling — Stewing — Roasting — Broiling — Baking — Frying — Fresh fish — Dried fish — Pickled fish — Canned fish — The bread and vegetable components — Flour — Bread — Hard bread — Pain de Guerre — Fresh vegetables — Potatoes — Onions — Tomatoes — Other vegetables — Cooking of fresh vegetables — Dried vegetable components — Beans and peas — Rice — Hominy — Oatmeal — Cormneal^ — Dried fruits — The sugar, coffee, and condiment components — Sugar — Molasses — [Saccharin — CoSee — Tea — Chocolate — Salt — Pepper — Vinegar. IV. Emergency or reserve rations — General considerations — The emergency ration — Emergency rations of foreign armies — Special preserved or concentrated foods — The travel ration. CHAPTEE VI. Military Clothing and Equipment, 293 I. General consideration of clothing— Uniformity — Cut — Grade — Material — Color — Permeability — Absorption and conduction of heat — Absorption of moisture — Water-proofing— Special articles of the uniform — The head-covering — The outer clothing— The underclothing— The coverings of the extremities. II. Equipment— Weight of equipment— Reduction of weight— Disposition of the equipment — Carrying apparatus — The mess outfit. CONTENTS. CHAPTEE VII. PAGE Camp Sites and Camps, 336 I. General consideration of camp sites— Topography— Soil— SoU-molsture and ground-water — Soil temperature — Bacteriology of soil — Vegetation. II. General consideration of camps— Plan of the camp— Area of the camp— Biv- ouacs— Cantonments— Shelter-tents— Tentage in general— United States army tentage — Tentage of foreign armies— Improvised huts— Frame quarters — Portable barracks — Permanent camps of instruction. CHAPTEE VIII. The Sanitary Administhation of the Camp, 374 The camp space — Habitations — Beds and bedding — The excreta— Garbage and refuse — Camp-police. CHAPTEE IX. Posts, Bareacks, Quarteks, and Hospitals, 403 General consideration — Location and arrangement of posts — Arrangement and plans of barracks — General principles of barrack construction — Barrack furni- ture and the care of barracks — Casemates — Guard-houses — Quarters — Hospitals — Occupancy of new buildings. CHAPTEE X. Ventilation, 446 General consideration of ventilation — Influence of ventilation on health — Ven- tilation in the United States service — ^Vitiation of air — Drafts, and the rate of ventilating air-currents — Superficial and cubic space — Amount of fresh air re- quired — Natural ventilation — Location and size of ventilating openings — In- take apparatus — Combined inlets and outlets — Extraction by heat — Ventila- tion by aspiration — Other means of ventilation — ^Examination of ventilation — Examination of air. CHAPTEE XI. Heating and Lighting, 491 I. General consideration of heating — Fuel — Local heating — Open fire-places — Stoves — Chimneys — Central heating — Heating by hot air — Heating by hot water — Heating by steam. II. Lighting by natural means — Lighting by artificial means — Unit of light — Mineral oil — Coal-gas — Acetylene — Electricity — Vitiation and heating of air by lights — Conclusions. CHAPTEE XII. Disposal of Excreta, Sewage and Refuse 533 General considerations — Cess-pit system— Pail system — Dry-earth system — Goux system — Sewerage — Sanitary value of sewers — Sewerage systems — Con- struction of sewers — Size of sewers — Velocity of flow in sewers — Gradient of sewers — Discharge from sewers — Sewer-air — Ventilation and disconnection of sewers — Care of sewers — Drainage and plumbing — Drains — Soil-pipes — Traps — Testing of plumbing — General considerations of plumbing — Water-closets and water-closet apparatus — ^Location and arrangement of water-closets — X CONTENTS. PAGE Night-latrines — Water-closet fixtures — Urinals — Flush-tanks — Disposal of liquid wastes — Disposal of sewage and refuse — Disposal of sewage into cess- pools — Discharge of sewage into bodies of water — Sewage-farms and ground filtration of sewage — Bacterial treatment of sewage — ^Disposal of garbage and refuse. CHAPTEK XIII. The Personal Cleanliness of the Soldier, 588 General consideration of cleanliness in the military service — Lavatories — ^Baths and bathing — Eain-bath systems — Post bath-houses— Care of the person in the field — The care of the feet — The care of the mouth — The care of the hair and beard — Insect parasites — Cleanliness of the clothing. CHAPTEK XrV. Military Mortality and Morbidity, 610 General consideration — Army medical statistics — Comparative loss in campaign from sickness and wounds — Death rates in civil and military life — Loss of time from sickness — Race as influencing military mortality and morbidity — Sickness and death rate as afEected by season — Locality as affecting health — ^Branch of service as affecting health — Influence of length of service upon morbidity and mortality — ^Age as influencing sickness and mortality — Influence of military rank as affecting health — Health of troops during peace — Decrease in rates under conditions of peace — War as affecting the health of armies — Comparison of military medical statistics. CHAPTEE XV. Diseases op the Soldier, 648 I. General consideration and classification — The infective diseases. — Cerebro-spinal meningitis-^Cause — Infection and dissemination— Prophylaxis ; Cholera — Oc- currence — Cause — Dissemination and infection — Predisposing causes — Prophy- laxis — Preventive inoculation; Dengue; Diarrhoea and diarrhoeal diseases — Prophylaxis; Diphtheria — Occurrence — Cause — Dissemination and infection — Predisposing causes — Prophylaxis — Preventive inoculation ; Dysentery — Oc- currence — Cause — Predisposing causes — Method of infection — Prophylaxis ; Enteric or typhoid fever — Occurrence — Cause — Elimination of infectious ma- terial by the sick — Methods of dissemination among troops — Predisposing causes to typhoid among troops — Prophylaxis — Preventive inoculation; Influenza — Occurrence — Cause — Dissemination and infection — ^Prophylaxis; Malarial fevers — Occurrence — Cause — Method of infection — Predisposing causes — Prophy- laxis; Measles — Occurrence — Infection and dissemination — Prophylaxis; Mumps ; Plague — Occurrence — Cause — Predisposing causes — Propagation and dissemination — Prophylaxis — Preventive inoculation ; Pneumonia — Occurrence — Cause — Dissemination and infection — Predisposing causes — Prophylaxis; Sacrlet fever; Smallpox — Occurrence — Infection and dissemination — Prophy- laxis — Vaccine material — Vaccinia; Tuberculosis — Occurrence — Cause — Dis- semination and infection — Predisposing causes — Prophylaxis; Typhus fever — Occurrence — Direct and predisposing causes — Prophylaxis; Yellow fever — Occurrence — Cause and mode of dissemination — Prophylaxis; General princi- ples of prophylaxis against infectious disease — Early diagnosis — Isolation — Quarantine — Avoidance — Abandonment — Individual hygiene — ^Artificial im- munization. CONTENTS. xi PAGE II. Diseases largely dependent upon exposure. Bronchitis; Rheumatism and myalgia ; Acute articular rheumatism. III. Disease produced by an improper dietary. Scurvy — Occurrence — Cause — Prophylaxis. IV. Diseases largely dependent on military service. Affections of the circulatory system. CHAPTER XVI. Disinfection .... 766 General consideration — Disinfection by physical processes — Desiccation — Sun- light — Incineration — Dry heat — Moist heat — Boiling — Streaming steam — Super- heated steam — Chemical disinfectants — ^Bichloride of mercury — Carbolic acid — Tricresol — Lime — Chlorinated lime — The hypochlorites — Ferrous sulphate — Chemical disinfection by the use of sprays — Gaseous disinfectants — Chlorine — Sulphur dioxide — Formaldehyde — Special applications of the disinf ective proc- esses — Room disinfection — Disinfection of stables — Disinfection of wells and cisterns — Disinfection of tentage — Disinfection of clothing — Disinfection of excreta — Miscellaneous — The sanitary oflBcer and his assistants. CHAPTER XVII. The Habits of the Soldiek as Apfbcting His ErFiciENCT, .... 807 Alcoholism — Classification of military drunkards, and causes of alcoholism — Prevalence of alcoholism among soldiers — Results of alcoholism — Use of alco- hol in the military service — Prevention of alcoholism— The army canteen, and its influence on the vyelfare of the soldier — Temperance clubs — Venereal dis- eases — Amount of venereal disease in the armies of the world compared — Syph- ilis — Gonorrhoea — All venereal infections — Causes affecting the prevalence of venereal disease among troops — Prevention of venereal disease — Effect of offi- cial control of prostitution — Measures of prevention of venereal applied to the soldier — The use of tobacco — Tattooing — The amusements of the soldier in relation to his health and efficiency — Insanity and suicide. CHAPTER XVIII. The Htgibnb of Hot aijd Cold Climates, . 850 General consideration of climate. I. The hygiene of the tropics. Effects of tropical climates — The physiology of the tropics — Acclimation of soldiers— Composition of military forces for tropical service— Season for arrival— Pood— The tropical dietary— Drink— Ar- tificial refrigeration — Shelters— Clothing — Cleanliness— Habits and personal hygiene — Conduction of marches — Sunstroke— Necessity for sanitaria — Dura- tion of service in the tropics. II. The hygiene of cold climates. General consideration — Selection of troops for winter service in cold climates — Clothing — Food — Shelter — Frost-bite — Snow-blindness — General sanitary rules for field service in cold climates. CHAPTER XIX. The Hygiene of the Troop-Ship, 923 Ventilation — Cubic space — Exposure to winds — Dryness of ship and decks — Condensation of moisture — The bilge — Location and arrangement of quarters for troops — Bedding — Cleanliness of person and surroundings — Clothing — Water — Food — Disposal of excreta — Sea-sickness — ^Exercise and amusements on board ship. xii CONTENTS. CHAPTEE XX. The Disposal of thb Dead 934 Interment — Method of Embalming — Transportation of the dead, with special reference to infectious disease — Sanitation of the field of battle — Cremation of bodies after action. CHAPTEE XXI. Sanitaby Inspections in the Mtlitabt Establishment, 942 Eesponsibilities and duties of the sanitary officer — Methods of sanitary inspec- tion — Special qualifications required of sanitary inspectors in the military ser- vice — Relations between the sanitary inspector and line officers — Recapitu- lation of the most important points to be noted by sanitary inspectors with relation to camp and garrison — Sites — Shelters — Water-supply — Food — Clothing — Bedding — Means of cleanliness — General police — Habits — Methods of exercise and amusements of the men — The physical condition of the men — The prevalence of diseases, etc. Index 949 THE THEOEY AND PRACTICE OE MILITAEY HYGIENE. CHAPTER I. THE SELECTION OF THE EECEUIT. Keceuitment being the fir* necessity in the organization of military forces the examining officer should bear ia mind that upon the faithfuMess and intelligence with which his duties are performed depend iu great degree the future health, efficiency, and mobility of an army. He should consider that war and not peace affords the theoretically normal conditions governing the military establishment, that physically sound troops are essential to success both in sudden emergencies and prolonged campaign, and that the soldier may be called upon at any time to sustain the maxi^ mum of fatigue and privation of which the human being is capable. Ac- cording to the first Napoleon, "the most important quality of the soldier iS his ability to support fatigue and privation; physical courage is only the second " — and it should not be forgotten that the effectiveness of a force depends upon its vigor rather than upon its size. The strength and health of a military organization is based upon the physical character of the indi- viduals composing it, and celerity of movement and the abiUty to bear hard- ship are imperatively demanded in the successful manipulation of armies. Eecruits must be of trustworthy physique and sound constitution before the military character can be developed, and the physically, mentally, and morally defective are hence to be uniformly rejected as unfit for service. Perfunctory performance of duty or inattention in this respect wiU often admit as recruits men whose physical faults render them unfit for duty and susceptible to disease, whose undetected affections may be transmitted to others or whose moral obliquities induce malingering and desertion. Such defects will early become evident in the company organization, and the eventual discharge of the soldier on account of pre-existing disability cannot fail to bring discredit on the skill and carefulness of the examiner. Little argument seems required to demonstrate the necessity for careful physical examination before enlistment; but it may be well to remember that during the war with Mexico the regular troops, who bore the brunt of the campaign, lost about two-thirds as many.from disease and by discharge for disabiUty as did the volunteer troops, the former having been physi- cally examined where the latter had not. In the Civil War the annual mortality from disease was 32 per 1,000 in the case of the regular army, and 55 per 1,000 from the less carefully examined volunteers. At the same time the annual loss by discharge on certificate of disability was 68 1 2 THEORY AND PEACTICE OF MILITARY HYGIENE. per 1,000 for the regulars and 91 per 1,000 for volunteers. In all foreign armies in which the physical standard required of the recruits is high, a,s m the German army, the rates for sickness and death are proportionately low. While military hygiene can do much to preserve the health of the origii:ially sound and robust, in the military service — as in the struggle for existence elsewhere — it is the weak and physically defective which are the first to succumb to liardship and disease. Hence, in the prompt rejection of the unfit, the future cares of the medical officer and the liability to epi- demics are proportionately diminished. It should be remembered that the evils resulting from a'higli sick -rate are not confined to the hospitals, the number and size of which, in an army of theoretically sound men, should be largely determiaed by probable casualty rather than sickness. The efii- ciency of the army is impaired not only proportionately to the number of absentees, but is also reduced through the extra expenditure of energy re- quired on the part of the effective force in performing the additional duties "which thus devolve upon them. The general efficiency is thus not only weakened, but it is weakened in. such a way as to seriously interfere with the process of repair. The places of the dead may be promptly filled with recruits ; but those cumbering the hospitals with their chronic disabilities are stiQ borne on their regimental muster rolls and cannot be replaced by more vigorous individuals so long as they are sick and are permitted to remain in the service. The ineffective man therefore weakens the ranks he was intended to strengthen. He serves but to fill the hospitals, load the trains on the march, consume supplies, and require the care of the effective and able-bodied to minister to his infirmities — and this at a time when his own services are wanted in the field. As expressed by Tripler, if the examiner keeps in mind that the strength of an army is determined by the number of rifles in tlie field rather than the number of names upon the rolls, he will be less desirous of accepting numbers of recruits than that those whom he shall have certified to be free from defect shall not fail in the hour of trial. Particular care is necessary in the examination of men for the volunteer service. The volunteer officers themselves are largely ignorant of the vital importance of rejecting the unfit and desire their regiments to be fiUed as soon as possible ; while patriotic motives inspire applicants for enlistment to conceal their defects from the examining officer. On being assigned to duty with newly raised troops, undergoing organization, the first duty of the sanitary officer is therefore to institute such re-examination of the personnel as will result in the elimination of all those unsuited to the profession of arms by reason of physical disabUity or mental infirmity. Defectives. — Weak or poorly developed men spend a large part of their time in hospitals, and in time of war are usually unable to render any service. As expressed by Greenleaf : "There is probably no one class of men which furnishes such large numbers to the hospitals, the guard- house, and the list of deserters as this, designated by military men as 'poor physique,' ' feeble constitution,' or 'general unfitness.' " This opinion is shared by Notter and Fhth, they believing also that a close correlation exists between the physical and moral development of men ; in fact, low- ering the physical means lowering the moral standard of recruits. Where THE SELECTION OF THE EECEUIT. 3 a service dips too low for its material it will be liable to get men not only small but unsteady, wanting in mental ballast as well as physical strength and resistance to disease. The nerves and muscles are built up by the same process of nutrition, and the weighing machine is probably the best of all means available for testiug the general fitness of the recruit. Nativity. — This, as subsequently shown, exerts a certain rafluence upon sick-rates and physical development. Contrary to the opinion en- tertained by the general pubhc, the standing army of the United States contaius no large proportion of men of foreign birth. Of 52,077 recruits accepted during the six years 1892-97, a period of peace, 70.69 per cent, were born in the United States. To still further insure that the army should represent the country at large and be in sympathy with republican institutions. Congressional action has recently provided that no applicant should be enlisted unless he was a citizen of the United States or had legally declared his desire for naturalization. Table Showing Nativity of 52,077 Eecruits Accepted foe Service in the United States Army for the Six Years 1892-97. 1893. 1893. 1894. 1895. 1896. 1897. Total. United States 6,346 300 53 9 897 218 8 21 8 11 96 67 153 880 72 80 15 19 22 71 19 23 5,789 338 65 8 841 189 14 22 9 12 112 73 139 812 64 71 22 9 33 80 13 17 5,040 237 58 13 708 129 8 21 5 13 89 53 116 706 45 84 4 8 9 47 15 26 6,285 197 50 9 652 141 12 22 9 17 78 46 116 769 38 83 10 11 6 59 14 19 6,498 218 37 7 643 133 6 14 5 13 70 46 101 645 40 62 14 7 14 49 13 19 6,850 214 49 4 713 123 6 23 7 9 69 49 139 743 63 65 20 10 13 41 10 18 36 808 England 1,504 312 Scotland Wales 50 Ireland 4,454 932 Canada ■Other British Possessions France 54 123 43 Holland 75 514 Norway 334 754 Germany 4 555 323 445 85 Hungary 64 Poland 96 Russia 347 Italy 84 Other countries 122 Total 9,388 8,732 7,434 8,643 8.654 9,326 53,077 Previous Status. — Class and occupation exert a marked and often characteristic influence upon susceptibility to disease, the physical devel- opment, and, in the latter case, the conformation of recruits. In our own service, enlistments for the regular army are usually made from the lower walks of life and the laboring classes ; but in time of war, and particularly in the volunteer forces, all sorts and conditions of men are attracted to the colors through motives of patriotism and love of adventure. This was especially noteworthy in the case of one of the cavahy regiments organized for service during the war with Spain. No figures affording a means of comparing the physical qualifications of the several social classes have ever been compiled from our military records, but this has been done to some 4 THEORY AND PRACTICE OF MILITARY HYGIENE. extent in foreign services. In a recent report of the British. War Office the physique of officers and enlisted men is compared, and it is shown that the " better classes " of society are also better physically. Officers, on entering the British army, average two inches taller, are from two to five pounds heavier, and have two or three inches greater chest girth than recruits ; and this in spite of the fact that the men average nearly two years older than the officers at enlistment. In the French army a similar comparison is greatly to the advantage of the officers ; and it may be ac- cepted that generations of breeding, unconscious selection, and more favor- able environment tell on the human animal like any other. As regards the one matter of vision, however, the recruiting officers of the British service have found that imperfect or defective eyesight increases with ascent in the social scale. It is, on the whole, less perfect among the better than the lower class of recruits ; and also, naturally, among those drawn from towns than those enlisted in the rural districts. The unequal physical development induced by occupation is so well recognized that no discussion of the subject is here required. In peace the United States army is recruited largely from the ranks of unskilled labor, with a fair proportion of clerks and mechanics. As a rule, these soldiers are men more of brawn than brain who enlist at first from no particular liking for the military profession but merely as a means of securing a present support — ^those who develop an aptitude for arms re- enlisting at the expiration of their term of service. The number of men enlisting in any one year from each class is naturally largely dependent upon the industrial conditions affecting their trade or handicraft. In periods of profound business depression an unusually desirable type of men become applicants for enlistment. Occupation of 9,585 Receuits Accepted in the United States Army in the Year 1892. Unskilled laborers 2,270 Soldiers and sailors, re-enlistments 2,130 Agriculture and stock-raising 1,235 Professional and commercial 899 Building trades 592 Workers with horses 496 Mines, metals and machinery : . . . 481 Dealers and workers in food products 336 Electricity and transportation 304 Workers in cloth and clothing 155 Unclassified 151 Personal service and attendance 148 Printing trades 121 Workers in leather 117 Makers of furniture and other workers in wood. ... 101 Workers in liquors and tobacco 34 Jewelry 20 Hatters 9 No occupation given 86 THE SELECTION OF THE EECEUIT. 5 In time of war, as above mentioned, the classes from which, the vol- unteer regiments are recruited differ somewhat from those from which the regular forces, in time of peace, are drawn. It is evident, of course, that a regiment raised in a large city will differ considerably from one raised in the country in respect to the previous avocations of the enlisted strength. The 161st Indiana Infantry, recruited during the war with Spain from country districts and small towns in that State, may, however, be accepted as generally typical in its constituency of volunteer forces. This regiment was composed as follows : Skilled laborers 413 Unskilled laborers 362 Farmers 296 Clerks 118 Students 58 Professional men 47 Merchants 25 Total 1,319 The average age of this regiment was 24 years, the average weight 149 pounds and the average height 5 feet 8 inches. Of the total number, 1,265 men were of American birth while 54 were of foreign nativity — 1,191 being single and 128 married. The military forces of Great Britain, the only European power in which the system of recruitment by voluntary enlistment prevails, are similar in their personnel to our own; laborers, servants, and farmers furnishing about sixty-five per cent, of the whole, artisans about fifteen per cent., and the remainder scattering. Physically, the regular troops are picked men while the volimteers are liable not to be so well selected in that respect. As might be expected, also, the city-bred applicants for enlistment are not physically equal to those from the country ; but, on the other hand, the consensus of opinion is that men from the rural districts break down more readily under military conditions than do those from cities. As stated by Woodhull, "the agricultural recruit will be better nourished and at first may appear the most vigorous, due to his previous life of moderate exercise in the open air, uninterrupted nightly sleep, and of stated and sufficient meals. His miad and body work slowly and generally best ia accustomed grooves. To him the plain and more scanty food, the garrison exercises, or the more fatiguing marches, the prompt obedience without discussion and the sharp movements without voluntary rest, the excitement of active service, the lack of comfortable surroundings when the day's work is over, and especially the exposure at night — marching on guard in all weathers with broken and insufficient rest — all these are conditions that disturb and lower his physical estate until he becomes inured to them. On the other hand, the young man from the city has been accustomed to all grades of physical and mental excitement, he has probably eaten spare, irregular, and poorly cooked meals, and has lived in crowded and ill- venti- lated rooms. He may have been insufficiently clothed, and has certainly 6 THEORY AJSTD PEACTICE OF MILITARY HYGIENE. bepn used to late and irregular hours and to spasmodic physical exertion. Both mind and body are more active, and, although the body may appear less stalwart, he represents the survivors in a struggle for existence which has not beset his companions from the country. Discipline is distasteful, but its methods and aims are more readily grasped. To him the military life is physical promotion, in that it substitutes regularity, system, and sufficiency for irregularity and inadequacy in meals, exercise, clothing, hours, and amount of rest and atmospheric purity. The new conditions disturb both classes, but to the city man less inconvenience follows. This is distinctly tested where city and country regiments lie side by side or where a city company has been incorporated in a country regiment. After elimination by length of service the country regiments rival those from the city in endurance, and generally excel them in the familiarity in the ways and with the implements of outdoor life." Age. — In time of peace age exerts a strong influence upon military morbidity and mortality, and during campaign its effect becomes much more apparent. It should be borne in mind that the real hardships of war happen during the performance of long and harassing marches with the incidental privations which precede actual conflict, and it is under these latter circumstances that the physical difference between the old campaigner and the young soldier becomes most manifest. All military experience is opposed to the enlistment of minors for active service, and lowering the age is well recognized as lowering the effectiveness of an army. In referring to the Indian Mutiny it was said by Gordon that " old regiments marched ia the most trying season of the year with compara- tively little loss by disease other than by epidemic cholera, while the young soldiers sent to their relief were literally dying by scores." It has long been known that "in campaign the young men succumb while the old soldiers become more hardy and stronger every day." In the Crimea, when notified that recruits were ready. Lord Eaglan replied that "those last sent were so young and unformed that they fell victims to disease and were swept away like flies," so he preferred to wait rather than have young lads sent out as soldiers. The Duke of Wellington looked upon old sol- diers as the " soul and strength of the army ; " and Napoleon, in calling for 300,000 men ia 1813, desired that they be "men and not boys, who serve only to encumber the hospitals." As stated by Marshall, "to accept re- cruits before they have acquired sufficient strength to qualify them to execute their duties and to undergo the fatigues of a military life is to multiply the victims of disease and vexation and to augment the expense of an army without adding to its strength." The French army which gained the day at Austerhtz contained no men below the age of twenty- two years, and marched upward of 400 leagues, leaving but few sick en route ; on the other hand, the army victorious at Wagram was mainly composed of young soldiers, who are said to have filled the hospitals and marked the roads with their corpses. In the Franco-Prussian war the later French levies suffered the most; and, in time of peace, in 1891, the hospital admissions of French soldiers were 219 per 1,000 for those having more than one year of service, and 316 per 1,000 for those less than twelve months with the colors. Soldiers in the German army vx the first two years of service furnish three-quarters of all the cases of typhoid THE SELECTION OF THE EEGRUIT. 7 fever. In 1883, of the British army in India, according to Eyre and Spottiswoode, 41 per cent, was under twenty-five years of age, and among them the death-rate from typhoid fever was 4.34 per 1,000; while among men twenty-five to twenty -nine years of age, forming 35 per cent, of the army, the mortality from this cause was only 1.50 per 1,000. According to Aitken, a large proportion of such soldiers as are discharged for disa- bility from the British service are under twenty years of age. Of our own service it is stated by Eosse that a decade ago the greater proportion of sickness occurred in the younger soldiers ; while up to the age of twenty- four the rate proved so much above the mean for the whole army that in ' 1881 the surgeon-general concluded that "it may fairly be questioned whether the services of these young men are equal to the cost of their maintenance." Laveran observed that during campaign in hot chmates the young recruits furnish a disproportionately large share of the sickness and deaths ; and Coustan is convinced that soldiers under the age of thirty years should never be sent to tropical countries. Eough states that "young men are more readily fatigued and much more liable to nostalgia, a condition which not only predisposes to sickness but aggravates its effects." Parkes considered the enlistment of boys of sixteen to twenty- one years a cruel waste, so great is the mortality at that age, and says that "although a recruit may be usefully trained at an early age no man under twenty can be regarded as an efficient soMier fit for service." Ex- perience has sufficiently proved the fact that the soldier must have att&.ined a considerable degree of maturity before he is able properly to execute the arduous duties and imdergo the privations incident to military life. On this point a lesson may be profitably learned from the Franco-Prussian War, when the German authorities, instead of fi llin g the ranks with the young and untrained lads included in the contingent for the year, preferred to send into active service the married men of thirty-five years and up- ward. Fallot, quoted by Ewing, states that "conscripts at the age of eighteen have not attained their full growth, and medical men are well aware that the complete development of the human body requires an ex- emption from great fatigue, abundance of healthy nourishment, undis- turbed sleep, and a tranquil mind — a concurrence of circumstances which never occurs in the army." From the standpoint of developmental anatomy the soldier should cer- tainly not be enlisted before the age of twenty-one years, and a delay of an additional twelve months would be not undesirable. At eighteen years the bones are not fully formed and their actual growth continues until the twenty-fifth year, osseous development preserving a distinct and definite sequence. The epiphyses of the transverse and spinous processes of the vertebrae hardly commence to ossify before sixteen years of age, and it is not until after twenty years that the two thin circular plates form on the bodies of the vertebrse, while the whole process is not completed until the^ thirtieth year. The sacrum commences to consolidate at the eighteenth year and the process is completed from the twenty-fifth to the thirtieth year. The fourth and third bones of the sternum are united between the twentieth -and twenty-fifth years, and the second is not united to the third' bone before the thirty-fifth year. The epiphyses of the ribs commence to grow between the fifteenth and twentieth and are not completely joined 8 THEOEY AND PRACTICE OF MILITAEY HYGIENE. to the bone until the twenty-fifth year. The epiphyses of the scapulae join between the ages of twenty-two and twenty-five ; while the epiphysis of the clavicle begins to form between the ages of eighteen and twenty years. The internal condyle of the humerus unites at eighteen, but the upper epiphysis does not join until the twentieth year. The epiphyses of the radius, ulna, femur, tibia, and fibula are aU unjoined at eighteen years and are not completely united until the twenty-fifth year. The epiphyses of the pelvic bones (crest of the ilium and tuberosity of ischium) begin to furru at puberty and are completed by the twenty-fifth year. The greatest growth of the heart takes place between eighteen and twenty-five years, and even at the latter age has not attained its maximum. When cardiac de- velopment is deficient, heart failure is liable to occur under unwonted exercise and in emergencies, and irritable heart, unfitting for military ser- vice, is thus favored. (Great importance must also be attached to age in relation to the gen- eral physical development of the individual. In height, weight, and chest measure the records kept of students at Amherst College show an increase up to the twenty-sixth year. Aitken states that the white American male grows 1.15 inches between the ages of nineteen and twenty -five. Eobert found that in French soldiers, observed during the period between the ages of twenty-one and twenty-five, the average increase in height was 20 mm. (.8 of an inch), while this increase of stature iu some instances was as much as 40 or 45 mm. Baxter noted that during the Civil War the native-born white recruits between the ages of thirty and thirty -five had an average greater height of .53 of an inch when compared with the stature of the whole army, ranging from eighteen to forty-five years. Audral foiuid that the maximum lung capacity is not attained until the thirtieth year, and that it diminishes after that time ; while Quetelet showed that the adult male does not acquire his greatest strength before twenty-five, his muscular power being stationary for the five years from twenty-five to thirty, and then diminishing. The results obtained by Quetelet are as follows : Age. Lumbar strength. Kilograms. strength ol both hands. Kilograms. Age. Lumbar strength. Kilograms. strength of both hands. Kilograms. 16 103 130 138 155 63 79 84 88 30 154 122 101 89 18 40 87 20 50 74 25 Statistics would seem to show that the maximum physical develop- ment is found in Americans between the twenty-fifth and thirtieth year; although it is estimated by Gould that the white native of the United States does not attain his full growth until between thirty-one and thirty- four years of age. It may be safely concluded, therefore, that the maxi- mum physical development is not attained before the twenty-fifth year, and that continuance of the present practice of allowing the enlistment of certain recruits as young as the age of eighteen years is, in this country of small military establishment and vast population, as undesirable as it is unnecessary. THE SELECTiON OF THE RECEUIT. 9 Where a minor offers the written consent of parent or guardian, the question then presents itself whether so young a person possesses the vigor and physical development necessary for the performance of all the duties of a soldier. Young men are more easily trained and moulded than are their elders, especially for cavalry, and when well led fight as well as far as mere physical courage goes. Young recruits, however, have not only to work but also to grow and develop, and hence should have precisely the quantity and quality of exercise best fitted for their needs. Under the conditions incident to campaign the staying power of the immatine youth is found wanting. His undeveloped body often yields to the strain and a consequent permanent disability leads to his discharge from the army and application for a pension. It is useless to expect any long- continued energy or exertion from the undeveloped and immature, and if such are to be enlisted this fact should be recognized and the work suited to their strength. " If the young man of twenty years has the maximum of suppleness and facility of accommodation to conditions, it is the man of twenty-five or thuty years who possesses the greatest vigor and stamina." The history of the past is full of evidence that too yoimg men are not fit for such duty as soldiers are called upon to perform, and hence their en- listment should be discouraged where it cannot be actually prohibited. The minimum age under regulations at which the recruit might be enlisted in our service has been practically constant at eighteen years; while the maximum has varied from the peace standard of thirty-five to forty-five in the early part of the century and fifty during the second war with Great Britain. In the CivO. War volunteers were accepted between the ages of eighteen and forty-five, but no drafts were made below the age of twenty years. In time of peace nearly all the original enlistments are imder thirty years of age; in 1897, of the recruits enlisted, 43.5 per cent, were between the ages of twenty and twenty -five years. According to Baxter, out of 190,621 whites. Union soldiers enrolled during the Civil War, the average age was 26.241 years. At the same time the proportion under twenty-one years of age, according to strength, was : 18 years 159.773 per 1,000 19 " 78.659 " 20 " 74.210 " Total under 21 years 380.479 " The following are the minimum requirements as to age, as given by Onslow, for recruits in various European armies : Great Britain ' 18 years France 20 Austria " 20 Germany 20 Eussia 21 Italy' 20 ' It is distinctly provided tliat recruits not arrived at their majority shall satisfy, through their unusual development, the physical requirements provided for men of twenty -one years of age. 2 The year the recruit becomes twenty. 10 THEOEY AND PEACTICE OF MILITAEY HYGIENE. In this connection the following figures given by Aitken for the British army in India, for the decade 1876-1885, are of interest: Under 18 years, per 1,000 strength 18-19 " 19-20 " 20-21 " 21-22 " 22-23 " 23-24 " 24-25 " " " , " Over 25 " " " 7.6 5.1 15.6 .50.9 70.4 87.8 94.3 91.3 577.1 In foreign services the necessity of maiataining large standing armies has caused a lowering«of physical standards which need not be adopted in our own army. With an abundance of material upon which to draw there is no reason for the enlistment of recruits who have not attained their fuU. physical powers. It would conduce greatly to the efficiency of the service if no enlistments were made among men of less than twenty-two years of age. Although immature men should never be accepted, it would be equally unfortunate to enlist those who are too old, and, with regard to the maxi- mum age for military service, it is probable that after thirty-five years of age the untrained recruit does not possess that flexibility and freedom of motion of the joints and that power of ready co-ordination which is neces- sary for acquiring the military education. Kirkhofif noted that after forty years the infantry soldier soon becomes unfit for service; and this fact is tacitly recognized in our army in the law which permits the retirement of enlisted men after thirty years with the colors. The legal limit for enlistment of thirty-five years of age is the very extreme for recruits under ordinary circumstances, and the nearer common laborers approach that age the more unlikely are they to be acceptable. It has been observed that for desirable colored recruits the age of twenty-five or twenty-six is prac- tically the maximum, since after that time they are liable to be physically stiffened and mentally dulled. For the determination of age in the recruit, as stated by Greenleaf, "certain well-known and clearly marked physical characteristics will enable the recruiting officer to decide at a glance whether or not an appli- cant for enlistment shall be placed in the broad mean as to age between the minimum and maximum fixed by law, although to determine in an individual either the age of majority — i.e., twenty -one years — or the max- imum age for enlistment, is alwajs difficult and often impossible. The desire to enter the military service is sometimes, from varying causes, so strong as to prompt certain youths or middle-aged men to resort to any deceit for the purpose of concealing the truth. Boys wOl announce them- selves as of age with unblushing effrontery, and men who are over the maximum will add to falsehood the most ingenious artifices to disguise the evidences of advancing age. The development of the body does not neces- sarily keep pace with its years of existence. Youths of eighteen or nine- teen years occasionally present many physical characteristics of maturity, THE SELECTION OF THE EECEUIT. H while some men pass the age of thirty -five without showing well-marked indications of it. Little importance need be attached to this latter phase, because the maximum limit does not apply to soldiers who re-enlist, and during peace but few civilians present themselves after that age. The former condition is, however, an important one and demands close atten- tion. The evidences of maturity which usually accompany the period of legal majority are as follows : At twenty-one years of age the wisdom teeth are usually cut, and on each side of both jaws there should be found five grinders, viz., three large double or molar teeth and two smaller double or bicuspid teeth. Under twenty-one years of age the wisdom teeth are seldom to be found. At maturity there should be some beard upon the face, and hair under the arms, a full growth around and above the genital organs, and some scattered hairs in the neighborhood of the anus. The hair of the body is generally fine and silky; while' after maturity it is thick and coarse in the various places mentioned. After maturity the skin of the scrotum is somewhat darker iu color than the surrounding parts, is opaque, and is marked in various directions by wria- kles or folds. Before this period such skia retains the soft, velvety con- dition of youth, its piak or flesh color, and is more or less translucent, while the wrinkles or folds are not well pronounced, or are entirely absent, particularly at the sides. This condition of the scrotum is the most valu- able of the signs of maturity." Height. — ^That stature is largely a question of race has long been demonstrated ; yet within racial lines it is a matter of class and, among classes, of age, occupation, diet, and environment. According to Kil- bourne, the following is the average height of the various classes from which the material for our army must be chiefly recruited : Feet. Inches. North American Indians 5 '''•93 United States whites (Union soldiers in Civil War) 5 7.67 Norwegians 5 '''■66 Scotch, United States immigrants 5 7.06 Canadians .' 5 7.01 Swedes, United States immigrants 5 6.90 Irish, United States immigrants 5 6.74 Welsh 5 6-66 American negroes 5 6.63 English, United States immigrants 5 0-58 Hungarians, United States immigrants 5 6.58 Germans, United States immigrants 5 6.54 Swiss, United States immigrants 5 6.38 French, United States immigrants 5 6.37 Poles, United States immigrants 5 6.30 Italians, United States immigrants 5 6.00 Austrians, United States immigrants 5 5-58 From the above table it is evident that in our service, the recruits for which are drawn from aU classes of foreign immigrant stock, the observ- ance of rules establishiag a fixed minimum is less desirable than in a country possessing a more physically homogeneous population. Deficient stature, when estimated according to the standard for each race, implies a lack of osseous growth which, in a large majority of cases, is accom- panied by proportionately defective muscular development and power, to- gether with lowered vital resistance. Mean height for different races. 12 THEORY AND PEACTICE OF MILITARY HYGIENE. however, is comparative and not absolute, and the height of sixty-two or sixty-three inches indicates degeneracy in the native American where the Latin of the same stature is not far removed in this respect from his racial normal. While with peace conditions an abundance of recruits can be ob- tained imder existing restrictions as to height — excellent when applied to native-born recruits — there should be some provision by which, for war service, the rejection of the comparatively undersized but muscular Slav and Latin, both notoriously hardy in campaign and in the performance of heavy manual labor, should not be obligatory upon the recruiting officer. While height has been accepted by some as being a physiological ex- pression of constitutional force, the vital resistance and endurance of the individual, as well as the maximum strength, is based rather upon the symmetrical development of all parts of the body. Beyer, however, con- siders that increase in height is a factor of the greatest importance in de- termining the ultimate degree of development in young men under physi- cal training, in which instance he considers that increased height means also increased strength; but the strongest individuals are not usually of great stature, and excessive height rarely implies a corresponding increase of general physical development and muscular power. Many centuries agq^egetius wrote that "it is of much more importance that the soldier should be strong than that he should be tall," and in the military service of the present day an even less necessity exists for men above the mean in size. The average stature of a youth of eighteen years of age, a "grow- ing lad," is a little over 5 feet 4 inches, and this increases gradually until he reaches the age of twenty-five years — about the stage of physical maturity or manhood — when his average height is between 5 feet 7 inches and 5 feet 8 inches. During the growing period the framework and vital organs receive their proper development, and considerable departures from the given average of proportionate height to weight indicate an impairment of these organs which may and probably will develop into positive disease after exposure to the hardships incident to the life of a soldier; hence they are of greater significance in men of these heights than in taller men, who are presumably of greater age and more mature growth. During the Civil War the average height, age and chest girth of 190,621 native white Americans, examined and accepted for the military service of the United States, was found by Baxter to be as follows : Mean age 36.96 years. Mean chest girth 35.25 mches. Mean height 67.35 " The minimum limit of stature for the recruit has varied greatly in our service. Shortly after the Eevolution it was fixed at 5 feet 6 inches, and in 1835 a minimum of 5 feet 8 inches for infantry was required. In 1838 it was reduced to 5 feet, but this was increased by 5 inches three years later. Before the end of the Civil War it was again reduced to 5 feet. At present it is placed at 5 feet 4 inches for all branches of the Height. Under 61 innhes Number. 609 61 to 63 (( 4 939 63 to 65 (( 21 713 65 to 67 u 47 731 67 to 69 u 58 348 69 to 71 u 38 935 71 to 73 il 14 858 73 and ovei 3.499 THE SELECTION OP THE EECRUIT. 13 service, although recruiting officers are allowed to exercise their discre- tion as to the enHstment of desirable recruits (such as band musicians, school-teachers, tailors, etc.) who may fall not more than a fraction of an kich below the minimum standard of height. The above requirement for height is, ftowever, subject to change, instructions to that effect being issued from the adjutant-general's office "from time to time as the re- quirements of the service may dictate." In foreign armies the minimum height of the soldier is at present fixed as follows : Meters. English 1.62 (64 inches). Swedish 1.60 German 1.57 Belgian 1.57 Italian 1.56 Austrian 1.56 Meters. Swiss 1.55 French 1.54 Russian 1.53 Spanish 1.50 Portuguese 1.50 (59 inches). It is a demonstrated fact that very tall men cannot for long support the fatigues of arduous military service ; and excess of height, in the ab- sence of proper and proportionate general physical development, is cause for rejection the same as a deficiency in stature. In men of great height the chief development is usually in the lower limbs, and in young and very tall recruits the excess of their growth becomes obvious by contrast with the narrow flat chest, in which the apices of the lungs closely ap- proach each other. Aitken noticed that the majority of cases of tubercu- losis in soldiers were found in taU men, and believed that the taRer the recruit the more his lungs should be tested with the spirometer — while Baxter found that during the Civil War the ratio of rejections increased with increase of height. According to Viry, the French grenadiers are notoriously inferior as marchers to the voltigeurs or infantry of the line. Men of large size require proportionately more food than do those of smaller stature, besides presenting larger surface to the bullets of the enemy. It is obviously an advantage to exclude men of great height from the mounted service and thus avoid the carriage of an unnecessary weight by the horses. For all arms of the service the enlistment of stocky, mus- cular men of medium height is most desirable. In our cavalry and light artillery establishment the miaximum height is 5 feet 10 inches; that for infantry and heavy artillery being governed by the maximum of weight, to which should be applied the rule for the proportion of height. Weight. — ^Weight, to be effective, should be chiefly in bone and mus- cle, since fat, more than is necessary for filling in and rounding out the figure, is dead weight and diminishes capacity to perform work. Weight varies directly with age and height and, according to Aitken, good weight for height is of even more importance than an ample chest measure. As a result of his investigations, Quetelet obtained the following figures : Age. Height. Meters. Body Weight. Kilograms. Age. Height. Meters. Body Weight. Kilograms. 17 1.634 1.658 1.674 52.85 57.85 60.06 25 1.680 1.684 1.684 63.96 18- 30 63 65 20 40 64.67 14 THEORY Am) PEACTICE OF MILITARY HYGIENE. The most important point to consider in regard to weight is the mia- imum compatible with military efficiency. Parkes placed the weight of 115 pounds as the minimum for the recruit of eighteen years of age, but at the same time advised agaiust the enlistment of such a class of men ; while, according to Fetzer, it is rare to find among men hating a height of 1.57 meters those who, weighing less than 60 kgm. (132 pounds), would make good soldiers. VaUin believed that men of a height of 1.70 meters should weigh not less than 60 kgm. and those of 1.80 meters not less than 70 kgm. Morache concluded that the weight, based upon the height, should be as follows : Meters. Kgm. Meters. Kgm. 1.55 56 1.65 61-63 1.60 58-60 1.78 63-64 The minimum weight for all recruits in our service is 125 pounds, ex- cept for cavalry, in which arm enlistment may be made without regard to a minimum standard, provided the chest measurement and chest mobility are satisfactory. Foreign standards place the average increase of weight with the height at about 0.75 kgm. for each centimeter of stature. The rule in use in our own service considers that up to 5 feet 7 inches twice the height in inches should represent the weight in pounds, adding 7 pounds for each inch above 5 feet 7 inches. This standard of weight may, with experienced examiners, be advantageously varied; since many young men of excellent bone may be temporarily under weight through defective nour- ishment, hard labor, or sojourn in hot climates, but be none the less vigor- ous and physically adapted to military service. The weakness of such men is apparent rather than actual. After twenty-five years of age, the body being fully developed, the excess of nutritive material over and above that required for its mainte- nance in health is deposited in the tissues as fat, and it will be found that a disproportion of weight over height occurs usually in adults or men in middle life. It is rare to meet in the recruiting rendezvous with very fleshy young men. Huxley regards the proper weight of man as 154 pounds. This, however, is much in excess of the mean for our military service, which, for men of twenty to thirty years, is about 145 pounds. It is better that recruits, if muscular, be over than under weight. Marked disproportion of weight over height does not disqualify for the military service, but positively obese men should be rejected. All things considered, the maximum United States army weight of 190 pounds for foot service is well placed, since the overweight man is handicapped by his superfluous flesh ; but it is weU to remember that a sedentary occupa- tion may favor a temporary inclination toward obesity which yields promptly to military conditions. In this connection the history of the recruit should be given some consideration, particularly in time of war, when men are urgently needed, and cases should not be judged too hastily on the basis of overweight alone. For cavalry and light artillery the maximum weight is wisely established at 165 pounds. Chest Measure.^ — The thorax, containing the heart and lungs, is the most important division of the body. It contains the vital machinery and THE SELECTION OF THE REOEUIT. 15 represents the staying power of the man. It must, therefore, be ample. The function of the legs is to transport the body ; they should be well formed and sufficient, but not unduly long — for length of limb at the ex- pense of the chest is a disadvantage. A long-legged, long-necked man with a short chest is objectionable as a recruit. The siiie of the chest is an excellent indication of the vital resistance of the individual. It should be large, well formed, and inclined to rotundity rather than flatness. As to chest measure, Leeland and Stolaroff concluded from their researches that in the properly proportioned individual this should exceed the half height by from 25 to 40 mm. Seggel, as the result of a large number of measurements, arrived at the opinion that if the width of the shoulders and the diameter of the chest sliould together equal or exceed the demi- height the recruit might be considered as acceptable. He believed that the width of the shoulders in connection with the chest measure should be recognized as an important factor in the selection of the soldier, placing this width, in the properly built man, at two-ninths of the height. Fetzer considered that a chest measure of 0.76 meter (30 inches) indicated the lowest limit of physical aptitude for military service ; but this standard, based on the necessity for a large number of men and on the comparati\'ely undersized population of southern and eastern Europe, is much too low for the native-born American recruit. Bernard showed that the frequence of respiratory and circulatory disease was in inverse ratio to the chest meas- urements ; while Mackiewicz, from the weight and measurement of seven hundred and seventy-one men invalided from consumption, demonstrated that among weak men, as determined by weight and chest measure, tuber- culosis occurred four times as often as among sound men. These results are borne out by common experience. According to Onslow, the minimum chest measurement for the recruit in various European armies is as follows : England 33 inches. France 30.86 " Austria 30.06 " Russia No limit. Germanj^ No limit.' Italy 31.5 inches. In Switzerland the chest measure of the recruit is required to exceed half the height. In our service the rule is that "a man whose chest measures less than thirty-two inches in circumference at expiration should be rejected, unless he be considered specially desirable, when the case may be reported to higher authority." The quantity of air introduced into the lungs at each inspiration is certainly one of the most important elements determining the vital force and physical fitness of the recruit ; and the mobility of the chest is in this respect one of the data most necessary to consider, especially with refer- ence to its relation with height and weight. Chest mobility does not nec- essarily mean chest capacity, however ; but where mobility is good capac- ity is usually satisfactory. Hutchinson states that the breathing capacity normally increases eight cubic inches for each inch of height between five and six feet. The vital capacity attains its maximum at thirty -five years of age, there being an average annual decrease of 1.21 cubic inches from that ' But the mobility and conformation are considered in connection with the general physique. 16 THEORY AND PEACTICE OF MILITAEY HYGIENE. poiat backward to fifteen and forward to sixty-three years of age. In general, the respiratory processes bear a close relation to the standard of nutrition of the organism. From a large number of observations in the British service the maximum chest expansion of a man of average size, eighteen to twenty-iive years, was found to be two to two and one-half inches ; rarely three inches. In our army "the chest mobility, i.e., the difference between the measurement at inspiration and expiration, should be at least two inches in men below five feet seven inches in height, and two and one-half inches in those above that height. It is not necessary that the applicant should conform exactly to the figures indicated in the rules, a variation of a fraction of an inch in chest measure being permissible if the applicant is otherwise in good health and desirable as a recruit." Of 9,901 men examined in Illinois for volunteer service during the war with Spain, the chest expansion was found imexpectedly high. The average in their case was 3.67 inches — ^where Baxter found that during the Civil War 315,620 native-born whites had an average expansion of but 2.807 inches. Among the volunteers above mentioned 4,067 men had a chest expansion of over four inches, and 801 of five inches or over. In examining the recruit the circumference of the chest is measured by passing the tape around it immediately at the point of the shoulder blade, the arm hanging down. Generally the tape will then be found to fall below the nipple. In taking this measure contortions of the body should be avoided. For the determination of the vital capacity the spiro- meter naturally gives more exact results than does the tape, but resort to this apparatus is unnecessary in practice. In the field, ill-adjusted packs tend materially to derange the chest organs. Even the canteen and haversack straps may press on the immature recruit to his lasting detriment, and, next to the inspiration of bad air, the imperfect or continuously obstructed expansion of the chest tends more than any other cause to bring about disease of the heart and lungs. In this respect, during campaign, the unformed chest of the recruit suffers much more severely than that of the seasoned soldier, and it is never advisable to accept the physically defective with the idea that the thorax wiU be devel- oped by a military life. As a general rule, large men are proportionately less developed as to chest than smaller men, but the influence of height on capacity of respiration is much greater than is that of weight. In obese individuals the chest mobility is never great. Average Proportions. — It should be understood that age, weight, height, and chest measure are very closely correlated in the growth of the healthy human being to the full development of his strength and powers of endurance, and that the maintenance of due proportions in these factors is absolutely necessary in order to enable the soldier to sustain the fatigue and hardships incident to the profession of arms. All the conditions of military life are established on the basis of uniformity ; and as far as pos- sibly average conditions of the above factors are required to co-exist. The march step is designed for men of mean height, not the very taU or short, while the weight of the equipment is proportioned to the average strength of the bearer. Hence the individuals above and below the normal line are at a physical disadvantage. All experience goes to show that the men most suitable for the military establishment are the typical men whose THE SELECTION OF THE BECEUIT. 17 -So ^|8 •nonB -aidsai I saa'jis •UOHB -jidxa CO coosepos.-t ^ -*t-Oi-ICO CO cocoeocccc CO CO CO CO CO CO S 53gS§S I S CO cojoeocojo I So i-it^o6'*co S IS 2S S coto»hS«5 CO COCOCOCOCO CO OCOCOCQgO I CO COCOCOCOff coco CO CO CO i£ Ss CO COCOCOC^CO CO •nonB -jidsni SS : ^ •noijB -JIdxa 8 : CO CO COCO CO •o toSo^o § Co COCOCOCQCO CO CO CD-* OS -HO :?2SS t- Oi-i^25§5 ^ ^&M«;lo CO TOCOCTCO^ eS CO eococogoco I co coco co fi ■nOBB -jjdsui •noijB -Jidxa 03 CO CO CQ SSS8' CO CO CO CO coco S S5SSS s CO COCOOSCOCO So CO CO CC CO CO ?s s? 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S^osS SS SfSSSS S3S3!8S g tjg^i^S 5; S^isSS SSSgS •Tuoq 5SKS S SS88S • -^i^giS 5 §555° ^j* -*25^^^ s ss ^s^'* si diss's rti StoSKi-- ^ S^SSSi ^ i$=g^^^ -^*i S-^S-SS ui lOtousoin u5 S3 5 •pajoioa IO^t1>CO CO ^xiXngCt »oS"*WCO 1-^ t-^ t^ L- t-^ CD EO ^ ^ ^ S5S 0-; •paioioo 8 -a««o S 00— jQt- t-^ b-I t^ 1-^ i--^ SSS8SS Wffi •TOOX lS38a IS82 8 £tSS SScocom 4Wfi® Ss UJOq :3SS^ ■ti'^irtr a; sss^g CO co^ffi.-i2s 1-H toSotCoS IffiSSS D t- t- ir ^; sssss ^.t-t~^t-I>. *P3J0[00 "^S-^^- (Mi-HrH ss I •P3J0I00 loSocOOS 3 S^S!SS •l«»ox io ^Sosao SggfJS u5*0"*coeo •TUoq , 1--OCO to in >— 1 C3 m i-lrHi-Hi-l ^ S« •aARBK t- x^ ?i -x- 5^ *--o5wg oco--i(»2 * -^ CO (M 5 '^os-iticoffi cooioaooo -«1 I CO CO - -r bo boS > CO ^rs "d s sS § c^K*5cSw coco coco CO 18 THEORY AISTD PRACTICE OF MILITARY HYGIENE. physical proportions vary the least from the common mean and who are naturally found in the great majority. The table on the preceding page shows the average height, weight, and chest measure of 9,226 recruits accepted for the United States military service m 1897 ; there being 6,062 native whites, 2,371 foreign-born whites, and 793 colored. The following standards for the United States service are based upon results obtained by skilled observers who, after careful study and the ex- amination of large numbers of men in civil and military life, have estab- lished the fact that there is an average proportion in healthy, fully devel- oped men between the height, weight, chest measurement, and chest mobility, which, however, will admit of slight variations without indicat- ing a departure from health. Height. Weight. Chest Measueement. Feet. Inches. Pounds. At expiration. Inches. ;Mobffity. Inches. 5A 64 128 82 2 5A 65 130 33 2 5A 66 182 33i 3 67 184 33 3 ^A 68 141 33i H ^inr 69 148 334 n Syi 70 155 34 2i 5t4 71 162 34i H 6 72 169 34f 3 6A 73 176 35i 3 In the British service, in 1886, of the men serving with the colors, 901 per 1,000 had a height of five feet five inches and upward ; 931 per 1,000 had a chest measure of thirty-four inches and upward, and 834 per 1,000 were over twenty years of age. Similar data with regard to the total en- listed strength of our own service are not available, but as compared with our raw recruits the trained British soldier possesses a slight superiority in chest measure, but is inferior in both age and height. The Examination of the Recruit. — The profession of arms is ardu- ous, and ample experience has shown the foUy of attempting to conduct military operations unless such men as are affected with disease, predis- posed to its occurrence, or are unfitted to sustain fatigue and exposure are excluded and eliminated fi'om the service. An effective or healthy mili- tary force cannot be' made from imperfect or immature men ; nor is it true that every man who supports himself by hard manual labor wlE make an efficient soldier, since aU his senses may not be keen, his joints not flexi- ble and he may not be souud. For determining the physical aptitude for military service many factors must be taken into consideration ; the requirements for recruitment neces- sarily varying with the social conditions of the different countries, as well as with the need for men. Some allowance may be made for blemishes, not affecting organic soundness, which have originated in the service in men who technically re-enlist, since their education in military matters and habits of discipline compensate for some minor weaknesses. In the foreign services, where conscription prevails, the lesser disabilities do not THE SELECTION OF THE EECEUIT. 19 as readily disqualify as with us, and a man unfit for one branch of the ser- vice is assigned to another. The leading characteristics of a good constitution are thus enumerated by Tripler : " A tolerably just proportion between the different parts of the trunk and members ; a well-shaped head, thick hair, a countenance ex- pressive of health, with a lively eye, skin not too white, lips red, teeth white and in good condition, voice strong, skin firm, chest well formed, belly lank, parts of generation well developed, limbs muscular, feet arched and of a moderate length, hands large. The gait should be sprightly and springy, speech prompt and clear, and manner cheerful. AU lank, slight, puny men, with contracted figures, whose development is, as it were, arrested, should be set aside. The reverse of the characteristics of a good constitution will indicate infirm health or a weakly habit of body." In general, a weak constitution will be better recognised than described, by the softness of tissue, slightness of form, insufficient development of the skeleton and muscles, and want of harmony between different parts of the body. " The examiner should endeavor to judge from the eyes, from the whole expression of the countenance, from the conformation of the limbs of those who are capable of making the best soldiers ; there are as certaia and as well understood indications for judging of the soldierly value of men as there are for ascertaining the qualities of a horse or a hunting-dog." The room in which the examination is conducted should be well lighted and large enough for the men to exercise in walking, running, and jumping, as every organ directly concerned in locomotion should be sub- jected to inspection. Only those persons who^e services are absolutely required should be present at the examination. The body of the recruit should be washed with soap and water before he is- presented for inspec- tion. " It is not believed to be good policy to enlist men who, though able-bodied and intelligent, appear at recruiting rendezvous in ragged or filthy dress, as the chances are such men are tramps and vagabonds and will not make good soldiers. Men who, though attired in clean and re- spectable clothing, are found to be filthy, in their persons should be promptly rejected for like reason." In the examination of the recruit he should, as advised by Greenleaf , take the position of the soldier in the best lighted part of the room, and be examined in the following order : 1. The general physique, skin, scalp and cranium, ears, eyes, nose, mouth, face, neck, and chest should be examined and the chest measure- ments taken. 2. The arms should be extended above the head, the backs of the hands being together, and the applicant required to cough vigorously ; any form of rupture is now readily discovered by the hand and eye. 3. The hands remaining extended above the head, the man is required to take a long step forward with the right foot and bend the right knee ; the genital organs are conveniently exposed and varicocele or other defects in the scrotum may be recognized. 4. The arms are dropped and the man required to separate the but- tocks with his hands, at the same time bending forward ; this exposes the anus. 5. The heart and limgs are examined. 20 THEORY AND PRACTICE OF MILITARY HYGIE:srE. 6. The elbows should be brought firmly to the sides of the body and the forearms extended to the front, palms of the hands uppermost ; extend and flex each finger separately ; bring the points of the thumbs to the base of the little fingers ; close the hands, with the thumb covering the fingers ; extend and flex the hands on the wrists ; rotate the hands so that the finger-nails will first be up and then down ; move the hand from side to side ; extend the arms and forearms fully to the front and rotate them at the shoulder ; flex the forearms on the arms sharply, striking the shoulders with the fists; extend the arms at right angles with the body, place the thumbs on the points of the shoulders, raise and lower the arms, bring them sharply to the side at each motion ; let the arms hang loosely at the side ; swing the right arm in a circle rapidly from the shoulder, first to the front and then to the rear ; swing the left arm in the same manner ; extend the arms fully to the front, keeping the palms of the hands together and thumbs up ; carry the arms quickly back as far as possible, keeping the thumbs up, and at the same time raise the body on the toes ; extend the arms above the head, locking the thumbs, and bend over to touch the ground with the hands, keeping the knees straight. 7. Extend one leg, lifting the heel from the floor, and move all the toes freely; then move the foot up and down and from side to side, bend- ing the ankle-joint, the knee being kept rigid ; bend the knee freely ; kick forcibly backward and forward and then throw the leg out to the sides as far as possible, keeping the body squarely to the front ; repeat these mo- tions with the other foot and leg ; strike the breast first with one knee and then with the other; stand upon the toes of both feet; squat sharply sev- eral times ; kneel upon both knees at the same time (if the man comes down on one knee after the other there is reason to suspect infirmity). Take the position to "fire kneeling"; present the back to the examiner and then hold up to view the sole of each foot; leap directly up, striking the buttocks with the heels ; hop the length of the room on the ball of first one foot and then another ; make a standing jump as far as possible and repeat it several times ; run the length of the room in double time several times. 8. The heart and lungs are re-examined. 9. The hearing of each ear is separately determined. 10. The vision of each eye is separately determined. 11. The test for color-blmdness is made. The duties of the examining officer will be materially facilitated if his clerk or assistant be instructed in the positions of the examination, as the re- cruit will usually find no difficulty in imitating the necessary movements. THE GENERAL aUAMFICATIONS OF THE RECRUIT. The Manual for the Medical Department requires that " in passing a recruit the examining officer is to examine him stripped; to see that he has the free use of his limbs; that his chest is ample; that his hearing, vision, and speech are perfect ; that he has no tumors or ulcerated or extensively cicatrized legs ; no rupture or chronic cutaneous affection ; that he has not received any contusion or wound of the head that may impair his facul- ties; that he is not a drunkard; is not subject to convulsions, and has no THE SELECTION OF THE RECRUIT. 21 infectious or other disorder that may unfit him for military service " ; also that the recruit must be effective, able-bodied, sober, free from disease, and of good character and habits. The' causes for rejection for service in the army of the United States, having relation to the efficiency of the soldier and his susceptibility to disease, have been well summarized by Greenleaf, whose admirable manual on the examiaation of the recruit, officially prescribed for the guidance of the examining officer, has been largely drawn upon in the preparation of this section. These defects, surgical as well as medical, may be enumer- ated as follows, a brief explanation being given to such abnormalities as are not self-evident disqualifications for military service even to the inex- perienced examiner: Mental Infirmities. — Insanity; Idiocy; Imbecility; Dementia. Moral Infirmities. — Intempekance in the tfsE oe Stimulants or Narcotics ; Conviction of Felony ; Masturbation ; Sodomy. — The moral character should be scrutinized with care in order that enlistments from the vagrant and criminal classes may be avoided. The recruiting rendez- vous is a favorite haunt for these men and a study of their personal char- acteristics will well repay the recruiting officer for his labor. "The enlistment of . . . intoxicated persons ... is forbidden." This regulation is intended not only to prevent the admission to the ser- vice of men who at the time of enlistment are under the influence of stim- ulants or narcotics, but of those who are of intemperate habits. Long indulgence in habits of intemperance will almost surely be indicated by persistent redness of the eyes, tremulousness of the hands, attenuation of the muscles — particularly of the lower extremities — sluggishness of the intellect, an eruption upon the face, and purple blotches upon the legs. Close and skilful questioning will often develop the facts connected with the antecedents of the applicant and materially assist the examiner in forming his opinion of the case. Even in time of war there should be no deviation from the rule that those who appear of undesirable character or personality, even if physically acceptable, should be promptly rejected. An army is always better without than with the^i. Cerebro-Spinal System. — Epilepsy; Chorea; All Forms of Pa- ralysis; Tabes Dorsalis; Neuralgia; Stuttering. special sisaxtalifications. Feebleness of Constitution (Poor Physique) ; Scrofulous Diath- esis ; Cancerous Diathesis ; Syphilis. — The last disease, recognized by its characteristic symptoms, is at all times cause for rejection. It will be most convenient, while making the general examination of the surface of the body, to search for evidence of a syphilitic nature. In the detection of this no single sign will suffice, although the presence of two or more should determine the matter, especially if the man admits having had a sore on any part of his penis or a chancre on any other part of his body. The rejection of men of poor physique, even if there be nd definite lesion or abnormality, is of the greatest importance. Such men are the first to succumb to hardship and to contract disease, while their lack of vital re- sistance renders their case mortality unduly high. 22 THEOEY AND PEACTICE Ot MILITAEY HYGIENE. The Skin. — All Chronic, Contagious, and Parasitic Diseases of THE Skin; NjEvi; Extensive, Deep, and Adherent Cicatkices ; Chronic Ulcers ; Vermin. — While skin disease of intractable nature is cause for rejection under usual conditions, in time of war exemption should be given only on account of long-standing or incurable diseases of the skin ; the milder forms may be treated with reasonable prospect of recovery in a short time, and the men should accordingly be held to service. A con- tagious skin disease should be cause for disqualification at any time. Ver- min indicate habits of uncleanliness which cannot be tolerated in the military service. Men whose constitutions have been broken down by poverty or vice are often the subjects of ulcerations of the legs, where the slight injuries to which so exposed a part is liable have failed to heal ; or if healed present large irregularly shaped scars, more or less discolored or adherent to the bone. These scars, being unhealthy, are liable upon slight irritation to be destroyed and the ulcer reproduced. Such men are unfitted for soldiers and should be rejected. Scars non-adherent, white and smooth, or even red, when recent, if apparently painless on manipulation, resulting from an incised or lacerated wound or a burn, not involving lesion of the sub- jacent organs, are not causes for rejection. In time of war conscripts may, with a design of evading service, purposely induce and keep open ulcers. Suspicion will naturally be aroused where a man, otherwise healthy, claims exemption from service on account of an ulcer of long standing; as this lesion is seldom seen except in persons of broken-down constitution and generally in middle or advanced age. The appearance of the ulcer and the tissues surrounding it will furnish some evidence as to its age, active in- flammation pointing to voluntary irritation and a recent lesion, while an old ulcer presents reverse characteristics. The Head. — ^Abnormally Large Head ; Considerable Deformities, THE Consequence of Fractures; Serious Lesions of the Skull, the Consequence of Complicated Wounds or the Operation of Trephin- ing ; Caries and Exfoliation of the Bone ; Injuries of Cranial Nerves ; Tinea Capitis ; Alopecia. — The scalp should be examined very carefully, by running the fingers through the hair, for depressions in the skull. If any are found that are deep and abrupt in character, especially if covered by a scar, the applicant should be rejected — the same applies to deformity of skull resulting from fracture. If the loss of hair is total, or if but a few tufts remain about the back of the head and the neighborhood of the ears, or if the scalp shows evidence of pre-existing disease, the applicant should be rejected. Considerable loss of the hair, either over the crown or above the forehead,, is cause for rejection. The military head coverings are not of themselves sufficient protection against heat or cold ; there should be enough natural covering in the hairy scalp to provide against suffering or disease from extremes of temperature. The Spine. — Caries; Spina Bifida; Lateral Curvature of the Cervical, Dorsal or Lumbar Regions; Lumbar Abscess; Eickets; Fracture and Dislocation of the Vertebra; Angular Curvatures, Including Gibbosity of the Anterior and Posterior Parts of thi; Thorax. — In lateral curvature of the spine rejection is demanded if an imaginary vertical line from the centre of the base of the skull falls one THE SELECTION OF THE KECRUIT. 23 inch on either side of the spinal prominences. Arching of the back, with flattening of the front part of the chest, are disqualifications when they exist to such a degree as to impede respiration or to interfere with the action of the heart. Men frequently present themselves for inspection with shoulders of unequal height. This is generally the result of habit, and is of no consequence unless connected with true curvature of the spine. The degree of this curvature, where it exists, will determine the eligibility of the recruit ; but, particularly in peace, recruits with rounded or unsym- metrical shoulders are not desirable, although they may be accepted. The Ears. — Deafness of One or Both Ears ; All Catarrhal and Purulent Torms of Acute and Chronic Otitis Media; Polypi and Other Growths or Diseases of the Tympanum, Labyrinth, or Mas- toid Cells ; Perforation of the Tympanum ; Closure of, the Audi- tory Canal, Partial or Complete, Except from Acute Abscess or Furuncle; Malformation or Loss of the External Ear and All Diseases Thereof, Except Those Which Are Slight and Non-Pro- gressive. — ^As the distance at which the' natural tone of voice may be heard in a closed room, when both ears are normal, is about fifty feet, the distance at which the applicant is to stand from the examiner in testing the hearing must be as great as the apartment will allow, not to exceed fifty feet. The applicant wUl stand with his back to the examiner, who is to address him in a natural tone of voice. When the distance is less than forty feet, it should be specified on the examination form, and the tone of voice lowered. Failure of the applicant to respond to the address of the examiner wiQ demonstrate a defect. The personal attention of the recruiting officer or sergeant must be given to closing the entrance to each ear separately, by pressing with the thumb the lobe situated in front of the opening to the inner ear. Advantage should be taken of the absence of other sounds to make the examination. Recruiting officers should re- member that a man may be totally deaf in one ear, and yet may hear all ordinary conversation perfectly if the sound ear is not completely stopped. Deafness of one ear is a bar to enlistment, but in ordinary occupations it might not be observed. Deafness may be caused by an accumulation of hardened wax; therefore an otherwise desirable recruit should have his ears well cleansed before final action is taken in his case. AD. men enlisted for the artillery arm of the service at a military post or assigned to that arm from a depot are required, before such enlistment or assignment, be- sides undergoing the ordinary examination, to be examined especially with a view to establishing the fact of the patency of the Eustachian tubes and the integrity of the tympanic membranes, in default of which the men are unfit for that arm. The Eyes. — Loss of an Eye ; Total Loss of Sight of Either Eye ; Conjunctival Affections, Including Trachoma; Entropion; Opacities of the Cornea, if Covering Part of a Moderately Dilated Pupil; Pterygium, if Extensive; Strabismus; Hydrophthalmia ; Exophthal- mia ; Conical Cornea ; Cataract ; Loss of Crystalline Lens ; Diseases OF the Lachrymal Apparatus; Ectropion; Ptosis; Incessant Spasmodic Motion of the Lids ; Adhesion of the Lid ; Large Encysted Tumors ; Abscess of the Orbits; Muscular Asthenopia; Nystagmus; Any Affection of the Globe of the Eye or its Contents; Defective 24 THEOEY AND PRACTICE OF MILITARY HYGIENE. Vision, Including Anomalies of Accommodation and Eefeaction; Myopia ; Hypermetropia, if Accompanied by Asthenopia ; Presbyopia ; Astigmatism ; Amblyopia ; Glaucoma ; Diplopia ; Colok-Blindness (for THE Signal Service Only). — The determination of vision requires the greatest care and patience on the part of the recruiting officer ; it is made with cards bearing the twenty feet test types and test characters. To use the cards, a distance of twenty feet is measured off ia a straight line ; place the applicant with his back to the light at one end of the liae, while the examiner stands at the other and holds the card exhibiting the test types or characters in full view of the applicant and so that a good light falls on the card. Each eye is examined separately, and if the applicant fails to read the test types or describe the test characters correctly, with either eye, he must be sejected. This standard for vision may be departed from in the examination of candidates for appointment into the Medical Corps of the army and in the enlistment of members of the Hospital Corps, and applicants accepted who are the subjects of refractive errors, viz., myopia, hypermetropia, presbyopia, and astigmatism, provided these errors are not excessive, may be entirely corrected by glasses, and are not progressive or accompanied by ocular disease. The object of this test is to exclude from the service men whose visual defects are such as to prevent them from be- coming marksmen. Successful use by the soldier of long-range fire-arms demands that his vision shall be normal or so nearly normal that there need be no question of his ability to see the target at all ordinary ranges. A large percentage of men are the subjects of slight visual defects, not to such an extent as to disqualify them for military duty, but sufficient to cause a little blurring or indistinctness in some of the letters of the required test, which may be increased by the nervous apprehension of failure. Ignorance, stupidity, or fear on the part of an applicant are factors to be considered in making this examination, and unless the recruiting officer exercises sound judgment he wUl probably reject men whose vision is in reality good ; hence plenty of time should be taken and slight errors, such as misreading a P or T for an F, provided the majority of the letters or test characters are read with facility, need not be regarded as failure of the test. The Face. — N^vi; Unsightly Hairy Spots; Extensive Cicatrices ON the Face. — Great deformities of the face — ^large, Hvid, hairy, un- sightly spots, loss of substance of .cheeks — are so many reasons for rejection, as they are calculated to excite aversion and disgust in others ; they may prove prejudicial to the service by provoking discontent in the quarters and by exposing the sufferer to cruel and irritating sarcasms and jests that too often end in fatal quarrels. Loss of the nose disqualifies the recruit, not only because it may be the indication of a constitutional disease, but be- cause the consequent modification of voice renders speech unintelligible ; and the same objections apply in the case of perforation of the hard palate. The Mouth and Fauces. — ^Hare-Lip, Simple, Double or Compli- cated ; Loss of the Whole or Considerable Part of Either Lip ; Unsightly Mutilation of the Lips from Wounds, Burns, or Dis- ease; Loss OF THE Whole or Part of Either Maxilla; Ununited Fractures; Ankylosis; Deformities of Either Jaw Interfering with Mastication or Speech; Loss of Certain Teeth; Cancerous THE SELECTION OF THE EECEUIT. 25 OR Erectile Tumors; Hypertrophy or Atrophy of the Tongue; Mutilation of the Tongue ; Adhesion of the Tongue to any Parts, Preventing its Free Motion ; Malignant Diseases of the Tongue ; Chronic Ulcerations ; Fissures or Perforations of the Hard Palate ; Salivary or Bucco-Nasal Fistul^e; Hypertrophy of the Tonsils Sufficient, to Interfere with Respiration or Phonation. — ^The con- dition of the teeth is to be considered solely with reference to the proper mastication of food. If there are not enough in the mouth for this purpose food is swallowed without the necessary preparation, and indigestion with imperfect nutrition and its consequent evils are the result. If several of the teeth are decayed, especially about the crown, it is probable that be- fore the expiration of an enlistment they will be so far destroyed as to ren- der mastication imperfect ; hence men who have lost the front teeth from decay and have' many unsound back teeth should be rejected. The loss of the front teeth through accident is not cause for rejection, provided a sufficient number of back teeth are sound. Unless an applicant has at least four sound double teeth, one above and one below on each side of the mouth, and so opposed as to serve the purpose of mastication, he should be rejected. Exception may be made by the adjutant general in the case of a soldier who desires to re-enlist, if a report is made showing his age, physical condition as to nutrition, and the number and location of the sound teeth. If the front teeth remain and the double teeth are gone, re- jection is demanded. If the loss of the natural teeth is supplied by artifi- cial ones the fact should be noted on the enlistment papers ; but the artificial substitutes cannot be considered as equivalent in value to the natural teeth, or as removing the disability on this account for military service. The Neck. — Goitre; Ulcerations of the Cervical Glands ; Cica- trices OF Scrofulous Ulcerations ; Tracheal Openings ; Wry-Neck ; Chronic Laryngitis, or Any Other Disease of the Larynx which Would Produce Aphonia; Stricture of the CEsophagus. — Goitre dis- qualifies only when large enough to interfere with breathing or the hooking of the collar of the coat, or if recent or growing. The Chest. — Malformation of the Chest or Badly United Eractures of Eibs or Sternum Sufficient to Interfere with Ees- piRATioN ; Caries or Necrosis of Eibs ; Deficient Expansive Mobility ; Evident Predisposition to Phthisis; Phthisis Pulmonalis; Chronic Pneumonia; Emphysema; Chronic Pleurisy; Pleural Effusions; Chronic Bronchitis; Asthma; Organic Disease of the Heart or Large Arteries ; Serious and Protracted Functional Derangement of the Heart; Dropsy Dependent upon a Disease of the Heart. — In measuring the chest the applicant should stand erect without muscular strain or rigidity. After the tape is placed in position and lies snugly and evenly upon the skin, and while the loose ends are held between the fijigers of the examiner so that when the chest is expanded the tape wiU run readily through them, the applicant should be directed to draw in slowly and steadily a long breath until his chest is inflated to its utmost capacity, when the record of chest circumference at inspiration should be read from the tape. He is then to expel the air by counting slowly and steadily from one onward until he can no longer resist the urgent demand for in- spiration, when the record of chest circumference at expiration should be 26 THEOEY AND PEACTICE OF MILITAEY HYGIENE. read. This should be repeated several times to insure accuracy. Many men are extremely awkward in developing their chest capacity on demand,, and great care and patience are necessary in getting true measurements. It is sufficient to require rejection that the chest should be ill-formed, that, its structure should appear to be too weak, and that the other parts of the organism should be stamped with signs "of debility and suffering." It is true the risk is run of rejecting men who may afterward become very robust and who, by a long and successful life, may contradict the opinion that may have been pronounced in their cases; but the army is not a public sanitarium, and " one will be astonished at the number of men who, received because no determinate lesion of the chest was recognized when they were inspected, succumb afterward with consumption, or whom it was- necessary to send back to their famUies with broken health after their strength had been exhausted." A feeble man left at home may become strong; but sent into the ranks he perishes almost certainly. Kecently. many cases of so-called "bicycle heart" have been found in applicants for enlistment. These are characterized by hypertrophy, dislocation of apex beat, rapidity and irregularity of rhythm. Such cases are cause for rejec- tion, since under hard service they would probably develop the irritable' heart so commonly found in the military service. The Abdomen. — ^All Cheonic Inflammations of the Gasteo-In- TESTINAL TeACT, INCLUDING DiAEEHCEA AND DySENTEEY; DISEASES OF THE LiVEE OE SPLEEN, INCLUDING THOSE CAUSED BY MaLAEIAL POISON- ING ; Ascites ; Obesity ; Dyspepsia, if Confiemed ; Hemoeehoids ; Peo- LAPSus Am; Fistula in Ano; Consideeable Fissuees of the Anus; Heenia in All Situations. — ^WhiLe hernia itself is a cause for rejection there is found in some men a condition of the parts through which the bowel would pass in the formation of a hernia that is known as " relaxed abdominal rings," and is considered by some surgeons as indicating a ten- dency to hernia. There is, however, no special evidence to show that hernia follows this condition with greater frequency than it does when the parts are normal. To exclude this class of cases would cause the loss to the- service of many excellent men, and it should not, therefore, be considered a cause for rejection. Eace exerts a marked tendency on the occurrence of hernia. According to Ssolomka, statistics gathered in the Eussian army show that while among the Eussians 1 man in every 250 was rejected for this cause, the proportion was 1 to 200 among the Poles, 1 to 175 among the Germans, and 1 to 35 among the Hebrews. Applicants from the latter race are, therefore, to be examined with especial care in this respect. Bleeding or internal piles are always cause for rejection ; the external variety, if recent, or if they are old and single, and the applicant asserts that they have never been painful or troublesome, do not disqualify ; but if there should be more than one old pile and they are larger than described, or if a single old pile is ulcerated or inflamed, or if there is a smaU. pile associated with varicose veins of the legs, the applicant should be rejected. The flabby folds of skin are not cause for rejection unless very large. The Genito-Urinary Organs. — Any Acute Affection of the Genital Oegans, Including Gonoeehcea and Veneeeal Sores; Loss. OF the Penis; Phimosis; Steicture of the Urethea; Loss of Both THE SELECTION OF THE EECRUIT. 27 Testicles; Peemanent Eetraction of One or Both Testicles With- in THE EXTEENAL EiNG; AnY ChEONIC DISEASE OF THE TESTICLE; HY- deocele of the Tunic and Coed ; Atrophy of the Testicle ; Varico- cele ; Malfoemations of the Genitalia ; Incontinence op the Ueine ; Ueinary FisTULiE; Enlaegement of the Peostate; Stone in the Bladdee; Cheonic Cystitis; All Diseases of the Kidney. — ^A sore upon the head of the penis, in the furrow immediately behind it or on the foreskin, is in the vast majority of instances venereal. This being the fact, the Government is entitled to the benefit of the doubt and these cases should be rejected. The same remarks apply to gonorrhoea. No individual can say positively that an attack of this disease, however mild, will not be followed by a stricture of the urethra. Stricture is frequently a sequence of gonorrhoea, for which reason aU cases of this disease should be rejected. Further, it is a contagious disease which should always be excluded from barracks. Other acute diseases, such as swelled testicle, simple inflammation of the foreskin and head of penis, may or may not be of venereal origin ; but it is safer to reject the man than to accept him and afterward have him rejected at the second examination or discharged the service at a subsequent date. Phimosis, if marked, is cause for rejection. This condition, although apparently trivial, is occasionally the cause of serious reflex disorders. It interferes with the free discharge of uriae and prevents a thorough cleansing of the parts from the natural secretions, which when retained act as an irritant, setting up inflammation and un- fitting the soldier for the performance of duty. Loss of both testicles by extirpation or disease, or marked atrophy of both or special sensitiveness of either, rejects. The absence of both testi- cles from their natural situation does not necessarily imply the loss of them from either of these causes, for they may never have descended into the scrotum. If the organs have been extirpated by accident or design the scar of the wound wiH reveal the fact ; if they have disappeared from atrophy some rudiment wiU stiU remain to show that they have descended. If neither of these signs be present and the testicles are not in the scrotum they are either still lq the abdomen or are arrested in the groin, where they may be felt and possibly seen as tumors or lumps, and may be dis- tinguished by the peculiarly sickeniag pain felt when they are vigorously squeezed between the fingers. If they occupy any portion of the groin they incapacitate the man from their liability to be followed by rupture, and particularly from their exposure to painful injury and to strangulation ; but if they are within the abdomen, and the man appears vigorous other- wise, the condition may be disregarded. These remarks are also applicable to those cases in which only one testicle is present ia the scrotum. Varicocele, when slight, is not a cause for rejection ; butit is presented to the examiner in so many degrees of development — ^from an almost im- perceptible enlargement of a few of the veins to a condition in which all of them are swollen as large as goose quills and completely fill, by then- mass, the scrotum — that the determination of the cases would be most perplexing, even to a medical expert, but for the rule formulated by Tripler, which; if strictly followed, wOl exclude from the service men thus physically unfitted. This rule is as follows : " If the testicle upon that side is atrophied, whatever may be the volume of the cirsocele, or if the 28 THEORY AND PRACTICE OF MILITARY HYGIENE. volume of the latter exceeds that of the former, the recruit should be rejected." Of 9,901 men examined for the volunteer service in 1898, varicocele, in varying gravity, was found in 21.17 per cent. Of all these cases only 6 caused rejection. It should be remembered that varicocele is markedly aggravated by service in hot climates. Affections Common to Both Upper and Lower Extremities. — Chronic Eheumatism ; Chronic Diseases of the Joints ; Old ok Irre- ducible Dislocations or False Joints ; Severe Sprains ; Relaxation OF the Ligaments or Capsules of Joints; Dislocations; Fistul^e Connected with Joints or Any Part of Bones; Dropsy of Joints; Badly United Fractures; Defective or Excessive Curvature of Long Bones; Rickets; Caries; Necrosis; Exostosis; Atrophy or Paralysis of a Limb; Extensive, Deep, or Adherent Cicatrices; Contraction or Permanent Retraction of a Limb or Portion There- of; Loss of Limb or Portion Thereof. — It is a matter of primary importance that the soldier should have the perfect use of all his limbs, and that the completeness and integrity of these organs should be in no wise impaired. Careful inspection of the limbs, even to the most minute de- tail, will therefore not be neglected by the officer who feels a proper in- terest in the good of the service or in his own reputation. Old dislocations, usually occurring in the upper extremities, if attended by any impairment of motion or distortion of the joint are cause for rejection. The applicant for enlistment will, of course, put the best face on the results of these cases and stoutly assert that the joint is as good as ever; but he should in aU cases be tried with a rifle, to see if he can perform quickly and easily the various motions required in the manual of arms and in the set-up drill. Even if motion is perfect it is doubtful policy to enlist a man who has any amount of distortion from a dislocated joint, because he has enough of a visible defect upon which at any time to hang an excuse for a discharge if from any cause the service becomes irksome to him. Fortunately, badly damaged joints are easily discovered, and the safest plan in such cases is to reject, even if the distortion or loss of motion be ever so slight. The same general remarks will apply to important fractures, especially if they have been in the neighborhood of joints. If followed by wasting of limb or paralysis there can be no doubt about the necessity for rejection. The Upper Extremities. — Fracture of the Clavicle ; Frac- ture OF the Radius and Ulna ; Webbed Fingers ; Permanent Flex- ion OR Extension op One or More Fingers, as Well as Irremedi- able Loss of Motion of These Part^; Total Loss of Either Thumb; Mutilation of Either Thumb; Total Loss of the Index Finger of the Right Hand; Loss of the Second and Third Pha- langes OF All the Fingers of Either Hand; Total Loss of Any Two Fingers of the Same Hand. — Rejection is necessary when there is mutilation of either thumb to such an extent as to produce material loss of flexion or strength of the member. The common distortion of the extremity due to contusion or felon need not disqualify. Special care should be used in the examination of the thumbs with a view to the ability of the applicant to use them in cocking the rifle. Permanent partial flexions of the little finger of one or both hands, due to the effect of some particular varieties of labor, do not disqualify, as they in no wise interfere THE SELECTION OF THE KECRUIT. 29 with the prompt and effective handling of arms. The permanent flexion of any other finger does, and should exclude from service. Redundant fingers are not always objections to a recruit. If the redundant finger is upon the outer border of the hand it is not usually in the way, and particularly if it be the left hand. The Lower Extremities. — Varicose Veins ; Knock-Knees; Club- feet; Splay oe Flat Feet; Webbed Toes; the Toes Double or Branching; the Great Toe Crossing the Other Toes; Bunions; Corns ; Over-Eiding or Superposition of Any of the Toes to an Ex- treme Degree; Loss of a Great Toe; Loss op Any Two Toes of the Same Foot; Permanent Eetraction of the Last Phalanx of Any of the Toes, or Flexion at the Right Angle of the First Phalanx of a Toe upon the Second, with Ankylosis of the Ar- ticulation; Ingrowing of the Nail of the Great Toe; Stinking Feet. — In young men, the development of varicose veins to a degree of prominence that would warrant especial attention is rarely met with ; it is more commonly found in men of thirty years and upward, particularly in those of intemperate habits or of feeble constitution. Mechanical obstruc- tion to the flow of the blood through the veins may also be the cause. Moderate prominence of the veins in men who are otherwise healthy, and who are temperate, need not disqualify; but it must be borne in mind that the tendency of this affection is to become aggravated, particularly in tall men, and upon long marches with knapsacks and arms. The character, then, of the veins should be well noted. Sometimes the minute superfi- cial branches only are enlarged. This is particularly the case in the space behind the knee and on the inside of the thigh, and is in itself of no conse- quence; but when clusters of knots are seen, or one or more single knots, large and with thin walls, or a network of enlarged branches are found about the ankle, the back of the foot, the calf of the leg, the ham of the thigh, or distinctly enlarged veins exist, that are not necessarily knotted, especially if extending above the knee, the man should be rejected. In all cases when there is chronic tumefaction, dropsy of the limbs, or marks of ulceration, rejection is demanded. The condition known as " knock -knee " sometimes, though rarely, exists to such a degree as to unfit a man for nulitary service. When dis- qualifying, it is impossible for the man to take the position of a soldier, and he is anatomically disabled from performing a long march. It would be said generally that if a recruit cannot bring the inner borders of the feet, from the heel to the ball of the great toe, within one inch of each other without passing the inner surface of the knees respectively in front of and behind each other, he is unfit for service. With regard to flat feet, the condition that renders a man unfit for service is that in which the arch is so far effaced, that the entire inner border of the foot rests upon the ground ; the inner ankle is very promi- nent, as is also the bone of the foot articulating with it, and the axis of the leg does not fall upon the centre of the foot— giving the effect that the ankle-joint has been dislocated and the foo t crushed down and outward. This extreme degree of! splay or flat foot is not often seen ; a broad and flat sole is common to the laboring classes, and particularly so among negroes ; but, unless an ill-fitting shoe is worn, this shape of the foot is not more 30 THEOEY AND PEACTICE OF MILITARY HYGIENE. likely to induce disability in long marches than is the arched foot of a more shapely mould. Eejection follows over-riding or superposition of any or all the toes to a degree that renders the wearing of a shoe painful; permanent flexion of the last joiat of one of the toes (hammer toe) so that the free border of the nail bears upon the ground, or flexions at a right angle of the last joint of a toe (usually the second toe) upon the second, with stiffness of the joint ; ingrowing nail of the great toe, usually the outer side, if deep and accom- panied with signs of inflammation or ulceration. Re-Enlistments. — When authorized by the War Department, the re- cruiting officer is permitted to accept men desiring to re-enlist and who present themselves for that purpose within the prescribed limit, "notwith- standing they may have some physical disqualification which would cause their rejection as recruits, provided they have no serious defect which would probably prevent the discharge of their duties as soldiers. In aU such cases the defects and the fact that they existed prior to re-enlistment will be noted on the soldier's enlistment papers." In modifyiag its require- ments for enlistments in this particular, it is the intention of the War De- partment to provide for the continuance in service of such faithful soldiers as have incurred disabilities during prior enlistments, which either do not or probably wiH not unfit them for duty in the future. Rejections. — Of the applicants for enlistment a considerable proportion are summarily rejected by recruiting officers, prior to any physical exam- ination, by reason of intoxication, obvious defect of body or mind, or on account of apparently undesirable personality. Such rejections are not made a matter of official record. Of those admitted to the physical exam- ination only about one in four has been found in times past to be qualified for the military service. In the five years 1889—93, the total number of applicants physically examined was 101,432, and of this number 85,136 were rejected, while 26,296, or 25.92 per cent., were accepted. During the past decade the physical attributes of the classes from which recruits were derived appear to have undergone steady improvement, the enlistments for the year 1897 showing the proportion of 702.19 accepted as fit for service per thousand examined. The colored applicants for enlist- ment have a somewhat higher physical average than the whites, the rate of acceptances per thousand examined being 786.71 for the former as against 695.16 for the latter. The causes of rejection on the primary examination with ratio per thousand of the 62,02^9 men examined, covering the four years 1894-97, are as follows : Tear. Total number examined Venereal disease (rate per 1,000) Other infectious diseases do. Diseases of nutrition, general do. Diseases of the nervous system do. Diseases of the digestive system. ... ..do. Diseases of the circulatory system ... do . Diseases of the respiratory organs. . ..do. Diseases of the genito-urinary system . do . 1894. 1895. 1896. 1897. 16,586 17,645 14,659 13,139 14.89 14.96 16.10 10.80 3.77 6.97 3.27 1.75 .36 .68 .27 .30 .78 .74 .48 .61 33.40 37.75 21.15 13.48 36.47 52.08 30.36 27.55 .84 3.83 1.03 1.53 41.30 40.92 33.36 23.53 Average. 15,507 14.19 3.69 .39 .65 26.19 36.61 1.55 34.77 THE SELECTION OF THE EECRUIT. 31 Year. Diseases of the lymphatic system and ' ductless glands (rate per 1,000) Diseases of muscles, bones, and joints do . Diseases of integument and subcuta- neous connective tissue do. Diseases of the eye do. Diseases of the ear do. Disca.ses of the nose do. Hernia do. Other injuries do. Over height do. Under height do. Over weight and obesity do . Under weight do. Imperfect physique do. Mental insufficiency do. Over age do . Minors do. Married or having dependent relatives do . Illiteracy do . Imperfect knowledge of English do. Re-enlistment disapproved do. Character bad or doubtful do. References none or unsatisfactory .... do . Aliens do . General unfitness do . No vacancies ,do . Unclassified do . Total per thousand 1897. Aver'affe. .72 5.37 8.80 77.73 5.25 2.47 7.72 4.40 .36 19.77 4.04 46.00 68.61 1.39 4.64 14.29 3.62 6.75 16.64 3.32 9.95 21.46 3.56 31.35 8.08 3.56 2.49 5.44 7.76 59.67 6.63 .91 11.50 5.04 .11 8.50 2.15 36.50 86.54 1.53 2.49 14.39 2.78 9.80 6.23 1.19 10.43 7.88 4.35 20.01 .17 3.10 1.84 4.57 8.53 51.50 4.09 1.98 6.75 3.96 .48 5.46 3.55 44.00 61.87 1.30 1.16 11.94 3.34 5.98 4.16 .55 7.37 10.98 1.91 11.94 1.91 4.57 1.83 4.11 5.10 37.14 4.26 1.14 5.33 3.97 .30 4.19 1.98 26.41 58.98 .83 .61 4.64 1.83 1.37 .23 3.13 5.10 5.63 .61 7.15 .53 2.83 1.73 4.87 7.55 56.50 5.05 1.62 7.83 4.09 .31 9.48 3.93 38.36 69.00 1.36 3.22 11.31 3.89 5.96 6.81 1.80 8.31 11.49 3.58 17.61 3.67 3.36 510.67 473.45 371.65 365.77 405.38 During the war with Spain an unusually good class of young men presented themselves for enlistment in the volunteer service. Out of 9,901 members of the Illinois National Guard who offered themselves for the United States service only 747, or less than 8 per cent., were rejected as being physically disqualified. It is proper to say that these men had already been examined for their militia service ; which examination, though not rigid, had eliminated the more obviously unfit. The causes of rejec- tion, as compiled by Adams, were as follows : General Gonstitutional Conditions. — Poor physique, 177; rheumatism, 13; syphilis, 14; tubercular diathesis, 3; premature senility, 4; obesity, 6 ; ancient sunstroke, 5 ; pediculosis, 2 ; chronic alcoholism, 1 ; chronic cutaneous affections, 3 ; asymmetry, 1 ; not stated, 6. Eyes. — Myopia, 13; strabismus, 10; defective vision, precise condition not stated, 35 ; leucoma, 6 ; keratitis, 1 ; tumor of orbit, 1 ; purulent con- junctivitis, 2; trachoma, 1; ai'tificial eye, 1; cataract, 1. Ears. — Otitis purulenta, 21 ; defective hearing, 24; mastoid abscess, 2. Teeth. — Extensive caries, 18 ; extensive loss of, 30. Nose. — Rhinitis, chronic, 1 ; dermoid cyst, 1 ; deformity with obstruc- tion, 1; chronic pharyngitis, 2. Throat. — Chronic laryngitis, 2. Neck. — Tubercular adenitis, 3. Chest. — Deficient expansion, 6 ; consolidation of lungs, 7 ; mitral lesions, 15; weak heart, 1. Deformities: Flat chest, 6; rachitic, 14; muscular atrophy, 2; old gunshot wound, 3; deformity not specified, 2; chronic ulcer of, 1. 32 THEORY AND PEACTICE OF MILITARY HYGIENE. Spinal Column. — Curvature, 4. Upper Extremities. — Ankylosis of shoulder, 2 ; ankylosis of elbow, 2 ; synovitis of elbow, 1 ; loss of fingers, 4; ankylosis of fingers, 4; drop-wrist, 1 ; deformity not specified, 1. Abdomen. — ^Hernia, oblique inguiual, 129 ; ventral foUowiug operation, 2 ; recurrent and chronic appendicitis, 12 ; pot-beUy, 3 ; chronic diarrhcEa, I. Genitals. — ^Varicocele, large, 5 ; varicocele with atrophy of testis, 1 ; hydrocele, painful, 8; cryptorchid, partial, painful, 1; tubercular testis, 2; epididymitis, 2. Venereal Disease. — Gonorrhoea, 18; gleet, 1; suppurating bubo, 1; chronic orchitis, 1. Zower Extremities. — Talipes, 3 ; flat feet, excessive or paiaful, 33 ; var- icose veins, 22 ; varicose ulcer, 3 ; unhealed gunshot wound, 1 ; deformed toes, 4 ; ununited fracture of great toe, 1 ; bunions, 1 ; corns, 1 ; ingrowing nail, 1 ; ankylosis of hip, 1 ; synovitis of knee, 3 ; loss of foot at ankle- joint, 1. Of the recruits examined for the British service in 1893 an average of 405.54 per thousand were rejected. The most frequent cause for rejection was defective development — the ratio being 181.78 per thousand; while impairment of vision was the next frequent disability and accounted for 41.51 rejections per thousand. Heart affections, diseases of veins, loss of teeth, and defects of the lower extremities were among the other causes and were arranged in the order given. Marshall divides the causes on account of which recruits are rejected into three classes : 1st. Diseases or deformities which a medical man from Ms professional training and acquaintance with the duties of the soldier considers are in- firmities which disqualify men for service in the army. 2d. Slight blemishes which do not disqualify a man for the army but which an unwilling soldier may exaggerate, and allege that he is thereby rendered unfit for military duty. 3d. Unimportant details or deviations from symmetry, or slight varia- tions from the usual form or condition of the body — teclinical or nominal blemishes which do not incapacitate a man for the army or in the slightest degree impair his efficiency. As stated by Greenleaf, experienced • surgeons will reject all recruits whose defects fall under the first two headings from a conviction that they render the men unfit or undesirable for the army ; but those under the third head are frequently rejected from fear of responsibility, a dread of official correspondence and to an ultimate damage to' professional character. In time of war those coming under the first head should be excluded, while those coming under the second and third heads should be as rigidly held in the service. CHAPTEB II. THE DEVELOPMENT OF THE EECEUIT. I. GENERAL CONSIDEBATIONS OF PHYSICAL T^AlNlTStiSr, Stebngth, activity, endurance and discipline, combined with, sound bodHy health, are the first requisites of the soldier; the foundation upon vrhich the whole structure of military efficiency rests. These quahties may be largely obtaiued by a scientific system of physical training, regu- lated by the fitness of those who undergo it, progressive in character and calculated to develop the body to its full power and perfect conformation. As applied to the recruit, physical training has a special technical value ; since, in addition to the qualities enumerated above, it does much to per- fect him in military duties and exercises, instructs as to the best manner in which to overcome the possible contingencies of actual warfare, and greatly aids to bring about that peculiar state of endurance and habit by which the soldier is enabled to support the labors and requirements of the military service. "It is false economy on the part of the nation and cruelty to the men to expose them to the privations of war and the fatigue incident to campaign without fortifying their constitutions and providing that reserve of strength, vitality, and endurance upon which they must draw and without which they will break down." If to physical ability be added the faculties of quick perception and prompt execution, the combination is of infinitely more value than the same amoimt of sluggish muscle piled on the back of a listless and in- different mind and an irresolute and halting wOI; these mental virtues being best developed by varied movements rapidly performed in obedience to the word of command. In the absence of such mental qualities it wiU prove of but little value to drill and instruct the soldier. The Untrained Recruit. — In time of peace the methods of recruiting employed in the army of the United States prevent the entrance into the service of men with muscles clearly undeveloped or such as are distinctly atrophied as the result of disease. Still, it is by no means uncommon that men are enlisted with defects or deficiencies sufficiently pronounced to exert a considerable influence on their health or value as soldiers during their term of service. Previous hard manual labor is far from being the equivalent of intelligent physical training. The deformities of occupation, due to the excessive use of one portion of the body and neglect of others, are well recognised; and variations of structure from this cause are so frequent that but a trifling proportion of accepted recruits are fairly sym- metrically developed. The idealr soldier is a man of commanding pres- ence, erect statiire, broad shoulders, strong, graceful and neat; and the 3 34 THEOEY AND PEACTICB OF MILITAEY HYGIENE. raw material from which these ideal conditions must be evolved is weU shown in Prince Hohenlohe's graphic description of the men obtained in the recruitment of his own regiment : " The barracks were soon full of figures that would put to shame the most exaggerated cartoons of the comic papers. The awkward fellows, whose neglected carriage made them look like a set of botched-up images, tried hard, but ta vain, to stand erect. Ill-made and ill-developed, their imiforms would not fit them, and if altered to suit their present figure would need to be remade when they should be remodelled by physical training. So, before teaching them a single movement of the military drill or providing them with uniforms other than their canvas fatigue suits, they were driLLed in gymnastic exercises leading progressively and gently from the more easy to the more advanced, until finally they had reasonable command of themselves." In such lack of harmony between various parts of the body lies a source of marked physical weakness in the recruit. The well developed chest and arms in the average recruit are more than likely to be accompanied by spindling legs ; while the limbs of the left side are usually smaller than those of the right, an asymmetry which extends to numerous other details. As a general rule, weight, height and breadth may be said to be in direct proportion to the strength — ^but exceptions are numerous and pronounced. Weight may be due to an excess of adipose tissue, tending to produce de- bility rather than strength. Height may be due to excessive length of legs or neck, both elements of weakness ; while breadth may imite with it flabby muscles and fatty deposits. Few recruits, if indeed any, are enlisted in whom devleopmental deficiencies are not at once apparent. Determination of Defects. — ^Accurate examination of the recruit win show his deviation from the normal type, from which the exercises necessary to assimilate him to the physical mean will be a natural deduc- tion. In this connection mensuration, inspection, and palpation are of particular importance ; but mensuration alone may lead to error in that one group of muscles may be over-developed so as to neutralize, in the measurement of a limb, the effect of the atrophy of another. The prelim- inary data upon which to base the physical training are, in the larger colleges, obtained by a considerable number of measurements; but this method, while eminently scientific and satisfactory in its results, is much too laborious and minute to be of practical application for the military service. In general, a proper course of training may be readily and satis- factorily outlined as a result of simple but careful inspection of the in- dividual. It should be remembered, however, that it requires most accurate anatomical knowledge to select the individual muscle to which a defective part owes its weakness or lack of symmetry. Not only is correct appreciation of its function necessary to imderstand the particular movement or combination of movements adapted to the development of a defective muscle, but to secur etlie best results there must be familiarity with its secondary and remote effects upon portions of the system. Hence proper physical training requires the careful supervision of an educated instructor to direct the exercises to the needs of the particular individual, and thus prevent the harm that may arise from the unintelligent and in- judicious use of what in well directed channels is a most important agent THE DEVELOPMENT OF THE RECRUIT. 35 in the attainment and maintenance of structural development and physical health. Exercise in Relation to Muscular Development and Power.— Exercise is_ usually regarded as implying action of the voluntary muscles alone, but in its effects it has a far wider range of application. Move- ment of the voluntary muscles is accompanied by corresponding action of the involuntary muscles ; and the condition of these, their health, and the activity of their physiological processes, depends greatly upon the impulses excited by voluntary motion. Every organ in the body is capable of being exercised directly or indirectly, and in such as are not properly brought into action an abnormal state is certain to ensue ultimately. As remarked hy Aitken, "AU the parts of the organization of man are connected and correlated so that with the increased or diminished dimensions of- the whole body, or any particular part of it, certain organs are increased, diminished, or modified ; and modifications which arise during the earlier stages of growth tend to influence the subsequent development of the whole man." Exercise increases the size and voluntary power of the muscles em- ployed. It accustoms these to unusual and extended effort and at the same time develops other muscles to assist in the execution of more com- plex movements. Under exercise against resistance the muscle increases in its nitrogenous constituents, growing by hyperplasia and becoming stronger. Such trained muscles are harder than the untrained, probably because of the increased power of simultaneous contraction acquired by the fibrillae. Within a certain limit, resistance to the shortening of a muscle makes it more able to shorten, and greater extension of the muscle places it in a state in which it can contract more powerfully. Hence, to be of the most value, exercise should consist of movements of sufficient force to necessi- tate energetic muscular contraction. Actual work must be accomplished, and the muscles should be so used that the exercise is felt and fatigue is noticed. This requirement necessitates resistance as an element, and hence physical exercise may be defined as voluntary labor. Resistance is necessary to obtain proper contraction of the muscles, the contraction for their molecular disintegration and the disintegration for their renewal, since upon the constant destruction and breaking down of tissue depends the subsequent renovation upon which the strength and vigor of aU parts of the body depend. Exercise as Affecting the Nervous System. — ^In addition to its effect on muscle, exercise may be employed to -produce prompt co-ordina- tion or for its effects on the nervous centres, which are quite as important as those upon the muscles. Proper physical training favors a symmetrical brain development, as exercise of the function of the centres governing the action of the muscles must favor the grovrth and development of those centres. Bodily exercise does not interfere with mental activity, and aU. nervous functions are by it improved in tone. Influence of Exercise Upon the Heart. — ^As a result of exercise the action of the heart is increased in both force and frequency. The heart stimulus is due to the increased amount of blood in its cavities, and the venous circulation supplying this blood is largely influenced by muscular 1 ©- 36 THEOKY AND PEACTICE OF MILITARY HYGIENE. action. "Every muscle is a little heart," and these by their contraction constantly tend to drive the blood on to the true heart and lungs. Exer- cise produces an enlarged heart; this beiag due to the fact that it is a muscular organ, and shows with other muscles both the fatigue due to violent and prolonged exertion, and also the iacrease in size and power due to proper exercise and nutrition. " The fatigue results in dilatation, the in- creased power in hypertrophy, and one of the main objects of traiaing is the establishment of this hypertrophy." The degree of dilatation following severe exertion is more marked in the young and inexperienced than in those who are well traiaed, and it is in the X. „ 1 A „ T^-i„f„«™ „» Tioorvt tio™.,.^ toiTneT ckss that acute dilatation, suflfi- FiG. 1. — Average Bilatation of Heart, Harvard ' Boat Crevr, after Eace. 1, Nipples ; z, before cient tO CaUSe CvanOSlS, IS Sometimes ob- race : 3, after race. (Aft«r Darling.) ■, r^ , • i ^ • - served, ouch an accident, occurrmg m the untrained, may often result in permanent injury ; while under the same circumstances the experienced athlete might recover apparently complete compensation in a few hours or days. To over-exertion, as in forced marches, is ascribed the condition known as "irritable heart." Hypertro- phy, rather than dilatation, follows long-contiijued exertion of low grade; while sudden effort, when severe, has been known to rupture a valve or weakened heart-wall. Hence the circulatory organs should be carefully trained before their powers and endurance are severely tested. The effect of continued and severe exercise being cardiac hypertrophy, persons who have such enlarged hearts frequently present symptoms of over-compensa- tion after the cessation of training. Under such circumstances the heart and arteries must re-adjust themselves to changed conditions, and there is some risk accompanying the degeneration by which this is accomplished. As a result of severe exercise, particularly when long sustained and carried to the point of extreme exhaustion, valvular murmurs of functional character are of frequent occurrence. The cause of these murmurs, in acutely dilated hearts, has been well studied by Williams and Arnold — ^no evidence having been advanced contrary to their conclusion that the bruits are of mitral origin, and are due partly to a relaxation of the circular muscular fibres surrounding the orifice, and partly to fatigue of the papillary muscles which control the movements of the valve cusps. These observers found such cardiac murmurs in eleven out of thirteen contestants in a long-dis- tance run examioed by them. As long as the heart is- not overtaxed the pulse beats are regular and even, though suddenly increased exertion may make the rate very rapid ; but the ordinary military exercise, when properly conducted, should not, after a course of preliminary training, increase the pulse rate more than fifteen to thirty beats a minute. If at the beginning of a new exercise the heart action becomes irregular, the work should be discontinued and later recommenced in a more gradual way. Loss of breath is due to cardiac embarrassment together with fatigue of the respiratory muscles. After unusual effort, provided that the exercise be not too greatly prolonged, the pulse is invariably of high tension ; but if the exhaustion be extreme the arterial tension falls much below the normal. It is to be remembered that THE DEVELOPMENT OE THE EECEUIT. 37 the physiological capabilities of the heart are enormous, and in judging of the effect of any undue exertion on it, the murmurs and irregularity must not be alone considered, but also the way in which the heart is doing its work, its strength, as shown by its ability to maintain a proper arterial tension, and its recuperative power. As with other muscles, not size but quality tells in the long run. Exercise in Relation to the Chest and Lungs. — ^The chest is the most essential factor of a soldierly physique. Its development necessarily includes tha,t of other portions of the body, for no one can perfect the capacity, bony frame and muscles of the thorax without also developing the back, loins and limbs. A capacious and mobile chest almost invari- ably means stout arms and, to a certain degree, good legs. During muscular action there is an increased demand for, and con- sumption of, oxygen and an increased production and elimination of carbon dioxide and other waste material. This demand for better aSration of the blood necessitates a considerably increased activity on the part of the respiratory organs — a man marching at the rate of four miles per hour in- spiring five times as much air as when reclining at rest — and this is one of the greatest advantages of physical exercise. Eespirations are by it in- creased in frequency and dbpth, the lungs expanded, the air vesicles flushed out and refilled. Consequently the movements of any given exercise should be with speed and force enough to deepen and quicken the respiration ; and conversely, if any severe exercise is to be undertaken or a course of training begun, especial care must be had to develop the lung capacity. Since action of the muscles is checked and rendered less vigor- ous if the carbon dioxide produced by their action is not immediately carried off by the blood and eliminated by the lungs, it follows that during exercise there should be nothing to impede the circulation or action of the chest or lungs, and that aU tightness of clothing, especially about the waist, chest and neck, should be avoided. Eespirations fall during sleep and appear to bear some relation in their frequency to the energy liberated ; the production and elimination of carbon dioxide under exercise being particularly large in recruits inclined to obesity. Among recruits, even if the chest measurements be satisfactory, shallow respiration is a common defect. The lungs are habitually only partially expanded, and in consequence, through absence of reserve power and the lack of air ia excess of actual ordinary needs — the result of inadequate vesicular dilatation — the individual becomes winded- upon unusual or pro- longed exertion. Breathing exercises, with voluntary forced expansion and • contraction of the chest, are most difficult of accomplishment by this class of men, they appearing to possess only to a limited degree the power of conscious control over the muscles of respiration. As the lungs contain little air beyond immediate respiratory needs, so the muscles of the chest are but little developed in excess of ordinary demands, and their free un- embarrassed action is the exception. The common and incorrect method of breathing among recruits consists in filling the upper and middle parts of the lungs at the partial expense of the lower. The collar bone and shoulders are raised, as is also the upper part of the chest. There is a slight movement upward and outward of the chest, while the lower part of the lungs remains passive, the diaphragm being but little used. As a re- 38 THEOKY AND PKACTICE OF MILITARY HYGIENE. suit of proper training a large portion of the lungs is utilised which is never used by persons of sedentary habits, the whole of the lungs and not merely the upper half being brought iato action. When breathing is correctly performed there is no movement of the clavicles and shoulders, but merely an upward and forward action of the sternum, more especially the lower part, combined with elevation of the ribs and with abdominal contraction and relaxation. Abdominal breathing should be particularly cultivated ; it not being forgotten that the diaphragm is as amenable to training as is any other muscle. The lungs should be filled slowly and emptied forcibly, regularity in this exercise soon increasing expansion and serving as an excellent aid in securing an erect, manly carriage and digni- fied gait. The increase of lung capacity depends largely on thoracic mobility ; an originally mobile chest, even if of small dimensions, favoring it greatly. Generally speaking, the younger the recruit the better the results which may be anticipated in this respect. The habit of breathing properly is a great factor in longevity, and a roomy thorax and strong heart are no mean allies in resisting invasion by disease. When the latter has actually gained a foothold a few additional cubic inches of respiratory capacity or a small reserve of disciplined cardiac power may suffice to turn the scale in pneum'bnia or typhoid fever. It is true that many comparatively undeveloped persons enjoy fair organic health, but it is equally true that greater respiratory and muscular power would unquestionably make such lives more effective and of longer duration. The influence upon the system of enlargement of the chest cannot be overesti- mated. The greater expansion permitted to the lungs, the greater play allowed the heart, the greater amount of oxygen introduced into the system, the greater excretion of effete matter from the blood — all these exert a powerful influence for well-being upon every cell of which the body is composed. To be truly strong the individual must be able to breathe deeply and well, and nothing is more certain in the military service than the dictum that " every inch a man adds to his chest measure adds to the measure of his days." Abel found in seventy-flve out of one hundred soldiers, examined after a 90urse in physical training, that the chest measure was increased from 2.6 to 5 cm. Marey noted among the men under instruction at Join- ville-sur-Pont that while after a six months' course of training the fre- quency of the respiratory movements was actually decreased, there was a notable increase in the amount of air inspired in a given time ; the exami- nation of a large number of men by means of the spirometer showing an average increase of respiratory capacity of 500 c.c. — ^rising from 3,800 to 4,300 c.c. At the end of the course of instruction he observed that ex- ercises which at the outset had rapidly induced breathlessness and exhaus- tion were readily performed with little or no acceleration of breathing. In the British service the drill sergeant endeavors not only to expand the chest but to keep it expanded. The recruit is required to hold himself upright with the head well back and the chest inflated by the fullest in- spiration, and this artificial dilatation is sought to be maintained without giving place to a corresponding exhalation. In this condition, as analyzed by Davy, the expiration, being held in abeyance, obstructs the circulation and impedes the cardiac action. With imperfect respiration the aSration THE DEVELOPMENT OP THE EECEUIT. 39 of the blood becomes imperfect, the abdominal muscles are weakened by overstrain and their action is impeded bj- forced depression of the diaphragm, while the increased measurement of the chest of the recruit is secured at the expense of its mobility and at the risk of emphysema. In this dis- tended chest the heart is displaced downward, the area of the impulse is increased, the beat is jerky and too powerful and may reach 110, with irregular force and time. This training is persevered in from day to day, making picturesque soldiers at the expense of their weakened vitality. Trainiog for strength and training for wind are two different things, attainable by quite di&erent means. Exercises which best favor develop- ment of the chest are those which relate to the upper extremities, and hence a course of gymnastic training is of particular value ia the attain- ment of this object. All track athletics also must be considered as respiratory exercise, and rapidity of performance adds to any movement the element of respiratory effort. A light dumb-bell may be Kfted and grounded so slowly as scarcely to quicken the respiration, or so rapidly as severely to test the wind. The voluntary muscles do no more work in one case than the other, but the involuntary muscles may do twice as much. Hence such efforts should always be preceded by scientific training. Exercise as Affecting the Kidneys. — As regards the effect of hard exercise upon the kidneys. Darling noted the occurrence of a slight in- crease in the excretion of urea — ^this probably being due to an increase in proteid digestion and not to an increase of muscular action. In his hi- vestigations upon the Harvard University crew for 1898 he found that a small amount of albumin persisted during ordinary training, whUe after racing the quantity was greatly increased. Under the latter conditions the sediment contained large numbers of hyaline and finely granular casts, many having renal cells and blood corpuscles adherent. This sediment was in many cases exactly like that in the first stages of an acute nephritis. The renal conditions during severe exercise he believed might be interpreted as an active hypereemia, becoming intense during extraordinary effort, and probably dependent on increased arterial tension. Whether such hyper- semia ever leads to permanent changes in the kidneys is a matter to be de- termined by future investigation. Apparently opposed to the above are the results obtained by Forrest from an exhaustive examination of the urine of 142 British soldiers, healthy and fi-ee from gonorrhoea, and marching from ten to twenty miles daily under full field equipment. He found that out of the 142 men, 14 presented albumen in the urine prior to beginning the march. In 9 of these 14 cases albumen was not subsequently found, on testing for it both before and after the daily march. The invariable effect of the day's work was either to abolish the albumen found before the march or to lessen the amount excreted. Marching exercise, however, is pro- tracted, and in it the element of sudden and severe exertion is absent. Between the steady but low-grade expenditure of energy in the one, and the brief but supreme effort required in boat-racing, it is evident that legitimate comparisons are impossible. Weight as Affected by Exercise. — It has long been recognized by athletic trainers that weight is one of the best indicators of condition. At the beginning of training a man always loses weight in fat, but it is usually more than regained later in increased muscular development, provided 40 THEORY AND PRACTICE OE MILITARY HYGIENE. sufficient food is given in proportion to the exercise taken. Ordinarily recruits gain weight, not lose it. Ammon, in a series of observations carried on upon a regiment of Baden grenadiers, found an increase in weight under exercise of about 2 kgm. ; almost identical results being obtained by Abel. At the gymnastic school of the French army at JoinvUle, as the result of the careful observation of eighty men, Burg saw the weight go up on an average of from 6 to 10 kgm., and be- lieved that this increase was due exclusively to muscular development. The results last mentioned, however, were obtained with selected men placed under conditions far more favorable to development than are foimd in ordinary military life, and such an unusual increase in weight is not ordinarily to be anticipated by the instructor. Eecruits as a class are not of an age or habit in which their weights can be greatly reduced by properly administered exercise, the greatest loss of weight naturally occurring in MAY JUNE 18 19 20 22 23 24 26 26 27 29 30 31 2_ 3 i 6_ e_ _7_ j_ 9_ i". 12 16 16 17 19 20 21 22 23 24 26 27 28 M I z 172 171 170 169 168 167 166 165 161 163 .^ -. •A ' 170 V o g s z ^ ^ z S r ■^ -N ^ ^i- ^ r ^ X- s. / ? V, J ^ 1G6 ie5 i i -I HO w AT HER . "t' 1 1 P H z il its 1 g ; . no. 2.— Average Dally Weight of Harvard Boat Crew under Training. (After Darling.) men of large girth and superabundant fat. Extraordinarily hard and exhausting exercise, even with conditioned athletes, when continued in- duces a certain loss of weight, as evidenced in the accompanying chart. Brief exercise, iE severe, may result in considerable temporary diminu- tion of weight. Maclaren observed upon himself that as a result of an hour's energetic fencing the loss in weight amounted to about forty ounces, of which about thirty-six ounces remained in the clothing as perspiration. When the exercise is more protracted and the individuals are unused to such labor, the results are for the time similar. In the First Munster Eegiment the weights ui one company were taken by Barry before and after a six days' practice march at the Curragh. It was found that : 7 men did not vary in weight; 12 lost one pound; 4 lost two pounds; 6 lost three pounds ; 1 man lost four pounds ; 3 men lost five pounds ; 1 man gained one-half pound ; 8 men gained one pound ; 3 gained two pounds. The net loss of the 47 men was 42.5 pounds, or a trifle over three-fourths of a pound per man. A loss of several pounds during prolonged exertion does not by any means imply an undue degree of exhaustion, provided the individual is in good condition. The men who lose most are usually fuUy as vigorous as their companions. It is generally accepted on experimental grounds that during active exercise the energy is largely if not wholly derived from the oxidation of fat and glycogen, and that the muscles themselves are not used up in the process. The end-products of this combustion — chiefly water and carbon dioxide — are rapidly excreted through the lungs and THE DEVELOPMENT OF THE KECEUIT. 41 skin. The loss of weight represents very closely, therefore, the amount of fuel used up. Hence the man who has an adequate supply of reserve fuel in the form of fat and glycogen is ia better condition to withstand a prolonged exertion than one who is deficient in those substances. This corresponds with the experience of aU athletes. There is always a loss of weight during the early part of training, while a man is getting rid of the superfluous fat; but every athlete knows that when a certain point is reached — ^his so-called "weight in training " — any further reduction is ac- companied by a feeling of lassitude and an incapacity to sustain prolonged exertion without excessive fatigue. This form of over-training, known as "staleness," is in aU probability due to a deficiency of reserve fuel. These facts emphasize the importance of maintaining at a proper proportion the fat and carbohydrate constituents of the dietary instead of sacrificing them for an excess of nitrogenous material — a mistake which is undoubtedly often made. Exercise as Affecting the Functions. — ^Exercise greatly increases the amount of perspiration, the evaporation of this surface moisture main- 102° lOf lOO' Jl/NE 16 17 ^7^ Fio. 3.— Temperature Chart of Harrard Boat Crew During Training and Immediately Before Race. (After Darling.) taining equability of the bodily temperature notwithstanding that heat is rapidly evolved. As soon as movement ceases the heat production is checked, the body cools off rapidly and the temperature may even become subnormal. Hence, following the cessation of exercise, there is great danger of chilling unless additional clothing be donned. After extremely exhausting exertion the temperature is markedly lowered. Williams and Arnold found the temperature of all the contestants in a long-distance run at least one degree below normal, while in three it fell two degrees and ia one four degrees. Prolonged training also appears to reduce the average temperature — as is shown in the accompanying temperature chart of the Harvard crew for the final fortnight of training — such reduction by many being looked upon as evidence of overtraining. The rise of tempera- ture noted at the end of the accompanying chart occurred immediately before the race and was presumably of nervous origin. Exercise increases the appetite, partly because of the increased demand of the muscles for food and partly on account of the increased circulation of the blood through the liver and vessels of the alimentary tract, causing a more rapid assimilation of the nutrient material ingested. After severe exercise an increased amount of carbonaceous food and of water is indi- cated to replenish the system in place of what has been eliminated. The increase of carbon is probably best given in the form of carbohydrates 42 THEORY AND PRACTICE OP MILITARY HYGIENE. rather than fat; and of all fluids, water is the best. As a general rule, alcohol is harmful because it benumbs and deadens the nerves and wiU; and, as every voluntary impulse must origiuate in the brain, anything that interferes with the communication between it and the muscles must lessen the promptness with which they respond and the consequent efficiency of their work. The use of a small quantity of malt liquor as a tonic during training for an athletic contest may not be harmful. Physical training, by lessening sexuality, conduces to morality and hence promotes military efficiency through the diminution of venereal affections. The positive value of exercise in diminishing genital irritabil- ity has. long been recognized. General Results of Systematic Exercise. — The physical benefits of systematic training of young soldiers are often very surprising. As stated by Eossignol: "Young men, whom one would consider very weak for supporting the hardships incident to mUitary service, acquire in a short time — after six months physical training — a general development of the body which one would scarcely be bold enough to hope for; and become, under the influence of exercise, strong and robust soldiers. " When physical training has been properly carried out, the men are educated to act with great cohesion, rapidity and accuracy; each soldier having his individuality developed, his intelligence sharpened, his interest excited, and the general monotony of his work relieved. By such training, individual serviceability is increased, and hence also that of the whole military establishment; while, on the contrary, the diminution of future pension roUs is accom- plished. In the United States army, though but little in the wa;y of systematic training has been done, the reports upon the results so far achieved are extremely favorable. With regard to the gymnastic exercises instituted some years since at recruiting depots, they were reported as being " severe and rapidly progressive, and giving noticeable physical development and elasticity of person, so that the individual is more quickly 'set up,' and sooner acquires good military carriage and movement." As a result of his work among recruits at Columbus Barracks, Butts obtained the following figures after a course of instruction extending over an average period of three and one-half months. II III II If hi III 11 n hi Average on arrival at depot » Average at departure from depot. 145.07 147.88 2.81 2.804 3.410 .606 36.53 37.18 .65 30.18 29.19 "!99 35 33 27 26 4.5 10.4 10.85 .44 13 12.5 9 9.25 1 12.05 12.66 .61 14 14.5 10.3 11 1.75 3.87 7.08 3.21 9 12 2 9 3.61 7.23 3.62 10 14 1 11 2.76 3.12 .36 3.5 3.75 2 2.33 1 8.32 3.71 .39 4.5 4.67 2.58 2.83 1.25 6.50 7.22 .72 9 10 4 5 2.25 9.50 10.99 1.49 Largest measurement at arrival. . Largest measurement at depar- 179 184 124 128 4.5 6 1.5 2 2 41.5 42 32 33 3 14.5 15 Smallest measurement at arrival. Smallest measurement at depar- 5.83 7 00 Greatest gains 13 13.5 5.25 Of the results obtained on cadets at West Point, a report from a former PLATE I. A. B. IMPROVEMENT UNDER PHYSICAL TRAINING. A. Condition at commencement of regular exercise. B. Condition of same man at the end of six months (After photographs by Way ) THE DEVELOPMENT OE THE EECEUIT. 43 superintendent of that institution stated that "the physical tests and measurements show marked average gaiu at the end of the first year's work of each class, in weight, wrist measurement, forearm measurement, upper arm extended and with biceps set, chest inflated and normal, and ia tests with horizontal bars, parallel bars, and broad jump." Much valuable work has been done by Beyer, upon cadets at the United States Naval Academy, with regard to the influence of exercise upon nor- mal growth. His investigations are particularly important in that the system of record in vogue at that institution renders possible the careful comparison of physical development when unaided by systematic exercise with that which ensued upon the establishment of a comprehensive course of physical training. Not only did he find a very marked increase in weight, strength, and lung capacity, as a result of physical training, but even the height of the cadets was much increased thereby, ^s shown in the following table recently officially submitted by him to the Navy De- partment. Height Standing. • Average Increase in Millimeters Between THE Tears— 16-17. 17-18. 18-19. 19-20. 30-21. Total. 1. From records of 4,537 naval cadets', nor- mal values 38 38 48 6 30 26 15 13 16 19 7 13 1 3 9 69 3. From records of 186 continuous individual 69 3. From records of 243 cadets influenced by 111 According to the above figures the total amount of increase in height, apparently due to exercise alone, and for the entire period of four years, is 42 mm., or nearly one and three-fourths inches. This result is cer- tainly surprising, and shows that the results of physical training are more far-reaching than had untU recently been suspected. The agent which can induce an actual growth of the skeleton of nearly two inches is surely profound in its effects; and a gain in bone, as opposed to that of muscular tissue, can not subsequently be lost. It should be remembered that these cadets were trained during a period in which there is normally consider- able growth, and that no such increase in height could be expected with soldiers of more mature years, in whom the bony framework has almost •completed its development. Beyer also noted that the taller the individual at the beginning of training, the greater also the increase in height, weight and strength induced by the exercise he is called upon to perform. Hence, in the selection of the recruit, he believes good height to be of prime importance. This can be accepted only within certain limits. Many accurate data from gymnasia and colleges are now available, which are of marked value to the military sanitarian. At Harvard the following average development, based upon a class of two hundred men, was obtained by Sargent. I In this number are Included several hundred who left but the records of a single examination, were afterward rejected in the mental examination, and consequently never became cadets. 44 THEORY AND PRACTICE OF MILITARY HYGIENE. Height Weight Chest (inflated) Chest (contracted) . . Forearm Upper arm (flexed) . . Shoulders (width). . . Hips Thigh Calf Average state of flevelop- ment upon entering gymnasium. 18.3 years. 67.974 inches. 134.981 pounds. 35.067 inches. 33.39 10.03 10.960 15.603 81.475 19.613 13.739 Average state of growth and development after having practised In gym- nasium half an hour a day four times a week for a period of sU. months. 68.354 inches. 137.133 pounds. 36.839 inches. 33.306 10.760 11.903 16.360 " 33.875 30.964 13.333 Average increase In vari- ous measurements after working halt an hour a day lour times a week, for six months. i inch. 3 pounds. 4 inch. 1 " * " 1 " t " 2i inches. 1* " i inch. The following table shows the effect of four hours' exercise a week for one year upon a youth of nineteen, working in the Harvard gymnasium. This was two hours' work more each week than was required of the regular class whose j-esults are noted above. Increase in one year Height. Feet. 145 160 15 36^ 40 Si g*' 34i lOi 11 13i 13J U s . at! 15f 17 li fl| 35 36i H 19f 33 2i g| m 15 1* In his work among the inmates of the New York State Reformatory, Way obtained most . gratifying results from physical training; the course of instruction being military marching and rifle drill supplemented by gymnastics and field athletics. Figures given by him are as follows : MBAStTRBMENTS SHOWING THE GaIN OF Six Men, Fotjs Months' CoUItSE. 13^ ^ a Strj;ngth in Kilogram of— Date. fS- 1 M |l ^S8 |i 1 1 O 1 i pa Soi June 10th 3,716 17 1,613 54.4 880 905 310 360 7 41, 110 90 1 17 October 10th . 1,630 56.3 880 930 310 365 8 50 161 ?.08 12 31 June 13th-. ... 4,011 17 1,569 47.1 770 795 364 380 8 30 90 100 5 18 October 13th.. 1,575 48.3 830 873 380 348 6 88 145 176 9 22 June 16th 3,639 18 1,637 50.8 800 840 330 335 3 28 75 110 14 October 16th . 1,646 55,3 890 955 280 361 5 32 107 134 7 29 June 17th 3,681 19 1,769 70.8 870 896 808 378 2 42 150 165 1 20 October 17th . 1,775 76.9 950 986 837 289 9 48 16(1 380 9 27 June 13th 3,530 19 1,736 68.5 830 900 384 248 1 31 100 110 2 12 October 13th . 1,743 63.8 930 956 804 261 6 50 149 260 9 38 June 17th 3,639 30 1,680 59,1 830 860 360 244 1 29 80 180 12 October 17th . 1,690 64.9 883 930 330 380 6 40 150 333 6 32 In addition to the above table the accompanying series of photographs by the same investigator show at a glance, and far more comprehensively B. IMPROVEMENT UNDER PHYSICAL TRAINING. A. Condition at commencement of regular exercise. B. Condition of same man at the end of six montlis. (After photographs by Way.) THE DEVELOPMENT OF THE EECKUIT. 45 than could be done by figures, the pronounced changes readily induced by properly selected and controlled exercise. According to Onslow, of the 15,504 British soldiers that completed their full course of training in 1887 in the military gymnasia of the United Kingdom, the average increase was : Weight, two and one-half pounds ; chest measurement, one and one-eighth inches; forearm measurement, one-half inch ; upper arm measurement, three-fourths inch — thus accom- plishing in chest girth in three months as much as had been gradually brought about, prior to the introduction of physical training, during the first five years of service with the colors. At one time twelve non-commissioned officers, selected from aU branches of the British service, were sent to Maclaren to qualify as instructors in mili- tary gymnastics. These men ranged between nineteen and twenty-nine years of age, between sixty-five and seventy-two inches in height, and be- tween one hundred and twenty-eight and one hundred and seventy-four pounds in weight. Of the results of the training of these men he says : " The muscfllar additions to the arms and shoulders and the expansion of the chest were so great as to have absolutely a ludicrous and embarrassing result; for, before the fourth month, several of the men could not get into their uniforms, jackets, and tunics without assistance, and when they had got them on, they could not get them to meet down the middle by a hand's breadth. In a month more they could not get into them at all; and new clothing had to be procured; pending the arrival of which the men had to go to and from the gymnasium in their great-coats. One of these men gained five inches in actual girth of chest." And Maclaren well adds: "Now who shall tell the value of these five inches of chest, five inches of additional space for the heart and lungs to work in ? " AU these men in- creased decidedly in weight — the smallest gain being five poimds, while the average was ten pounds. One man gained sixteen pounds in less than four months ; and it is unlikely that any of this increase was due to fat. Every man's chest enlarged decidedly; the smallest gain during the four months was one inch, the average two and seven-eighths, and the largest — in a man twenty-eight years of age — ^five inches. And he adds : " But the greatest of all changes, a change which I could not record, was the change ia bodily activity, dexterity, presence of mind, and endurance of fatigue ; a change a hundred-fold more impressive than anything the tape measure and weighing-chair can reveal." Again, from the Eoyal Military Academy at Woolwich, Maclaren took twenty-one cadets having an average age of eighteen years, and ia the brief period of four and one-half months obtained an average advance of one and three-fourths poundairu-weight, two and one-half inches in chest, and one inch on the upper arm ; while one slender youth of nineteen gained eight pounds in weight, and five and one-fourth inches around the chest. To gain five inches of chest girth and nearly that amount of lung, heart, and stomach room, with a consequent greater capacity for all the vital organs, is a matter, to any man, of almost immeasurable value. Kigal noted that chest capacity might iacrease even if the circum- ference diminished, a fact which he believed to be due to the absorption of fat. He found that among the weaker men at enlistment the greatest increase in weight ultimately resulted. Fetzer found that ia the French 46 THEOEY AND PKACTICE OF MILITAEY HYGIENE. army the chest capacity of 292 recruits had increased an average of half a liter after ten months of training. In a study of the Sixteenth Army Corps, FriQey noted that in 5,999 recruits there was an average gain of 5 millimeters in height, of 1.058 kilograms in weight, and of 12 milli- meters in chest measure. Mandoul, experimenting with two hundred and thirty men of the Twenty-second Infantry and a number of young men of the Third Hussars, arrived at analogous results, as follows: Increased height, after serving one year, 6 millimeters ; increased chest measure, 15 millimeters ; increased weight, 2 kilograms. In analyzing their results at the French military school of physical training at Joinville-sur-Pont, Chassagne and Daily found that 76 per cent of 401 men examined showed an increase in chest measure of 20 to 30 mOlimeters. In the same number the circumference of the arm was increased in 332, forearm in 250, and thigh in 258. The dynamometric force of the two hands increased in 344 cases (86 per cent.), decreased in 42 and remained stationary in 15. In the great majority the increase in strength was from 25 to 30 kilograms. As a result of physical training they found that " young men develop in chest-girth and muscle, the weak in strength, the awkward in agility, and the timid in confidence." In the military service the obvious results of exercise include develop- ment of the muscular system, increase of the respiratory capacity, stimula- tion of the nerves, and diminution of adipose deposits. Apart from these well recognized results, however, it should not be forgotten that the increased girth of the extremities is not the only indication of their added strength, since it does not take into the account their firmness and contractile power gained even before the growth began. " The quickened sympathy between brain and muscle is not readily demonstrable, nor are suppleness, agility, and self-confidence to be represented in figures." Although the effects of exercise are particularly notable in the former artisan or city-bred recruit, any man who has received judicious physical training as a soldier can readily be distinguished from his fellows who remain in civil life. He has a springy step, an erect and easy carriage, his abdomen is retracted, his head is mobile but well raised, his chest is expanded and his shoulders are squared. Exercise as Influencing the Occurrence of Disease. — ^With regard to the part directly played by physical training in the prevention of disease but little investigation has been done, and sufficiently elaborate statistics are lacking. Hitchcock, however, in his observation of students at Amherst College, believed that systematic exercise redounded to the general health in that institution, the average sickness among the seniors being about half that constantly prevailing among the freshmen; and similar conclusions have been drawn by Sargent as a result of his work among the students of Harvard University. Of the correctness of these conclusions common experience is witness. A certain amount of muscular exercise has long been recognized as being highly beneficial in health, and as actually necessary to the proper performance of organic function. Life must be considered as essentially organization in action. Physical training undoubtedly promotes health as weU as strength by quickening the circulation and increasing the respiratory powers. Systematic exercise aids in resisting disease, since, as a result of muscular action, healthy and PLATE III. A. ^^H (K^^ ^^^ ^^* ■* ^^H ^■. w^ ^M (h^i . IMPEOVEMENT UNDER PHYSICAL TRAINING. A. Condition of youth 16 years of age, immediately prior to entering upon a systematized course of exercise. B. Physical condition of same youth at the end of three months. (After photographs by Way. ) THE DEVELOPMENT OE THE EECEUIT. 47 active tissues take the place of weak and sluggish ones, glandular and organic functions are stimulated and waste material is elLminated. Its directly favorable influence in the maiatenance of health and the prevention of disease cannot be gainsaid. "A fine physique once gained is never whoUy lost. He who has satisfied his physical obligations, whose credit with nature is good, is not visited by her heavy penalties for subsequent shortcomings. " Government of Exercise. — ^Physical training should be begun and increased with moderation, and is not to be continued after great fatigue is manifest. Too violent exercise under any circumstances does more harm than good. The movements to be employed should be from time to time prescribed, and their execution systematized, in order to avoid injury arising from an unwisely selected and unintelligently executed exercise, or the development to an abnormal degree of any particular portion of the body. AgOity in the soldier is rather to be desired than great strength, and most recruits possess considerable muscular development and little activity. Hence the efforts of the instructor should be largely directed toward suppling the joints, and educating the men properly to use the strength they already possess. This is best done by light but continued exercise, for the trained use of an organ renders it more effective in the performance of its functions. While securing the modicum of agility and strength in the soldier the true aim of physical drill is to develop and keep in good health the whole body. To ensure the greatest advantage from physical training there should be a record book kept of each company, and an examination made each month by a medical officer with a view of noting the progress made, dis- covering the neglected parts which need strengthening and instituting such course in each individual case as wiU tend to gradually develop and perfect the entire system to a sound and healthy condition. Should a man have difficulty in executing an exercise, readily accomplished by his comrades, he should be carefully examined to ascertain if any physical cause can be found to accoimt for it, especially as regards his heart. The best time for exercise is midway between meals, preferably in the forenoon from two to three hours after eating. Physical training in the early morning before breakfast is wrong in every respect, and may then result in as much harm as it is, when properly timed, capable of doing good. Men just risen from bed are wanting in nervous energy, have relaxed muscles, and are not physically prepared to undergo fatiguing exercise. If such a plan be long maintained a noticeable rise in the sick rate will surely follow, particularly in a malarious country. Early morning setting-up drill is a not infrequent fad of commanding officers which mUitary sanitarians wiR do well to discourage. If exercise be taken too soon before meals, either the stomach, by calling the blood from the exhausted muscles, will prevent their proper repair and rest ; or the muscles, calling the blood from the stomach, wUl prevent the proper supply of gastric juice. If exercise be taken too soon after eating, it is apt to prevent the flow of blood to the stomach and the formation of gastric juice ; or by forcing the contents of the stomach into the intestines before gastric digestion is completed, and before the food 48 THEOEY AND PEACTICE OF MILITAEY HYGIENE. has reached a condition in which the intestines can make use of it, to cause intestinal irritation and indigestion. As to duration, in beginning the physical traiaing of the recruit not more than fifteen minutes' gymnastic or setting-up exercise should be re- quired at any one time. Later the men can receive with advantage one hour's physical training daily, preferably half in the morning and half in the afternoon ; this being contiaued for five days during each week. The duration and severity of the exercise should be increased gradually, and iu beginning or ending the daily period of instruction the lighter movements should be chosen. The exercise should be suspended whenever the men show signs of muscular weariness or of being out of breath. The pulse also is to be ob- served when necessary. If it become irregular or its rate rise to 130 or 140, a rest should be required. It should not be forgotten that severe sudden effort may rupture a muscle, tendon, or even bone of attachment, and that hernia is liable to be caused by too Adolent gymnastic exercise. If drills or gymnastics must take place indoors, the room should be large and well ventilated ; but as a general rule men should be exercised in the open air rather than in buildings. In rainy or very hot weather these driUs are advantageously carried on in sheds or porches. During rests and after periods of work the men should not be chilled by exposure to currents of cold air. Whenever' possible, the exercise should be followed by a cool shower bath for the maintenance of comfort and cleanliness. If this is not obtainable, the men, if heated, may rub themselves dry with towels before going into the cold air outside; and, after exercising, additional clothing should under aU circumstances be donned to prevent chilling. Thirst may be satisfied by drinking cau- tiously — if necessary at frequent intervals. The amount of energy to be expended should be intelligently con- trolled. The usual estimate of the minimum amount of daily muscu- lar exercise required to keep a man in healthful condition is that it should be about 150 foot-tons; or equal to a walk of about nine nules, without weight-carrying, on level groimd. That this is no great amount will be readily appreciated if it is considered into how many appar- ently unimportant movements the daily expenditure of energy is divided. For the accomplishment of the physical development of the soldier a greater amount of exercise is required, and when this is properly distrib- uted over several groups of muscles, a daily average of 300 to 350 foot- tons as the total amount of work to be done is probably not too large an estimate. Without adequate preparation even the strongest man is unfit for great exertion. A young recruit cannot keep pace with a fuU grown and com- pletely trained man in the ranks, mainly because his heart and blood vessels are not fuUy developed nor specially trained. Failure arises usually from attempting too much at the outset; and with excessive work at the beginning or with a sudden increase, as in forced marches, such youths rapidly break down. The taking of exercise merely for its own sake soon becomes to most men a task for which they grudge the time. Exercise should always be recreation. Unless it gives pleasure and relaxes mental tension at the B. mPROVElVIENT UNDER PHYSICAL TRAINING. A. Condition at commencement of regular exercise, B. Condition of same man at the end of six months. (After photographs by Way.) THE DEVELOPMENT OE THE EECEUIT. 49 same time that it occupies the limbs exercise becomes labor — an added strain and not a diversion. The movements employed should be subjected to wide variation. Those giving general development as well as those educating special groups of muscles should be employed; but such con- stant repetition as makes the work mechanical and tiresome should be avoided. When accompanied with music and perhaps varied by simple changes of formation, the object desired will be obtained without undue fatigue. Except in the purely military exercises, such as the setting-up and bayonet drills, the men should not be held under the strictest restraint and military discipline ; and too great severity during general gymnastics should not be used in repressing the signs of interest and pleasure which may be excited by competition and exercise. Purely mechanical movements, by their monotony, will become weari- some and lose their efficiency. Hence the best exercises for the soldier are those in which he does not simply obey a command mechanically, but employs his mind and body under the influence of present necessity — fencing, wrestling, and boxing being of particular advantage. The best results of exertion are often obtained by directing the mind and efforts to- ward some other object ; and thus purely gymnastic exercises can scarcely be as satisfactory as out-of-door games and athletic contests. The instructor should render the work as agreeable as possible, and in taking due precau- tions against injury he should avoid exciting apprehension. Muscle and mind must be gradually educated, and both undue tension and Ul-regulated effort serve to retard development. It has long been noted that physical training in general, but particularly athletic sports, exerts a marked effect no the morale of troops as well as on their physical condition, rendering men more interested in their work and contented with their lot. This has its influence in diminishing the evils of desertion and drunkenness. Division of Exercise. — Pilcher divides the physical training of the recruit into two parts. The first builds up to symmetry and muscular harmony men whose physique is below standard, imparts that ready com- mand over the muscular system which follows thorough training, and contributes to the quickness of mental apprehension only to be derived from exercising in response to frequently varied commands. The time during which the recruit should remain in this class is very variable, depending on the amount of deviation from tire normal type and the readiness of re- sponse to-trgatment. The second class of training is purely conservative and aims at the maintenance of a well-balanced bodily condition. After this has once been secured, very little effort suffices to overcome the retro- grade tendency characteristic of all forms of life when stimulated to a higher grade ; but a certain degree of training must be constantly maintained, and the exercises, though not arduous, should be numerous and varied. During the first period the recruit should be held imder medical supervision to ensure proper direction of the training and prevent excess of apphcation — but when he passes into the second class the medical inspection may be much less minute, though never to be entirely withdrawn. Training. — In the technical sense, to " train " is to lead the most health- ful life possible while by appropriate exercise the body is prepared for some supreme effort. Diet is plain but otherwise unrestricted, but alcohol and tobacco are to be tabooed except on, rare occasions. From eight to ten 4 50 THEOEY AND PRACTICE OF MILITARY HYGIENE. hours' sleep should be prescribed. The methods of training employed of course vary accordiag to the results desired. Under any circumstances it should be slow and progressive, nothing beyond the power of endurance being required and the heart and lungs being gradually adapted to the unusual labor they are called upon to perform. Training will not be employed in the military service save in the case of the few individuals who enter into department or other athletic competitions. Exhaustion. — If the physical' training of the soldier be not properly governed the condition known as exhaustion soon supervenes; this being a guard against over-exertion as hunger is against inanition. Fatigue may be due to lack of sufficient contractile material in the muscles to do the work required or to the exhaustion of nerve force and the weakening of the motoi: impulses from the brain, but is imdoubtedly largely determined by the accumulation of carbon dioxide and other waste products in the organism. In any case the sense of fatigue cannot be taken as the measure of actual muscular exhaustion, since under the influence of fear or excitement men frequently accomplish feats which, without such stimulus, they have previously declared themselves unable to perform. The wiQ, in fact, rarely if ever calls forth the greatest contractions of which the muscles are capable. In general, the symptoms of fatigue are similar to those of fever. Muscles undergoing frequent contraction become painful, and if fatigue be great the heart becomes weak, the arterial tension falling from impaired cardiac action. Signs of exhaustion naturally occur first in the weak, young or illy developed ; and hence, as the personal equation varies so greatly, it is a difficult matter to determine other than by actual experi- ence the maximum amount of exercise which could be taken by a given individual. When a large number of men are being exercised together the capacity of the weaker rather than the stronger must be considered as the standard. Drill must be within the powers of endurance, and the young soldier, usually keeping up too long fi-om pride, should be encouraged to fall out of ranks when distressed and remain quiet until normal circula- tion and respiration are resumed. It is well, at first, to stop short of actual fatigue ; and hence recruits should be drilled with moderation, particular care in this respect being given the yoimger men. The results of exercise, beneficial if the task be moderate, are quite different if it be carried on to the point of exhaustion. Eigal noted among the Twelfth Chasseurs that following severe manoeuvres in a mountainous country the weight di m i n ished, as did also the chest measure. He observed many cases of exhaustion, and noted that the men admitted to hospital had lost on an average six kilograms of their weight. Excessive exertion, espe- cially when combined with exposure to cold, is a fruitful source of nervous disease, and during winter campaigns nervous weakness, myelitis and tabes are common maladies of soldiers. In hot coimtries excessive fatigue plays a most important, if not, indeed, essential part in the causation of sunstroke. Exhaustion, especially when frequently repeated, renders the soldier an easy prey to disease of an mfectious nature. L^ques noted that the French soldiers of the Alpine districts are particularly liable to typhoid fever, a fact which he attributed largely to the exhausting character of the duties required of these troops. AU foreign military sanitarians appear to agree with Czernicki and Coustan that the increased sick rate from typhoid THE DEVELOPMENT OF THE EECEUIT. 51 fever among troops during manoeuvres is largely, though indirectly, depend- ent on physical exhaustion. Overtraining. — The common symptoms of this condition are well known. They are, in brief, a loss of strength and endurance, so that a man previously strong becomes incapable of prolonged effort. This may be accompanied by a general nervous restlessness, listlessness, a loss of weight, insomnia, and various digestive disturbances, such as anorexia and diarrhoea. These symptoms should not be confounded with the tem- porary collapse which is occasionally seen after a severe exertion, and which is more apt to be due to undertraining than to overwork. The con- dition known as overtraining may often be seen in soldiers engaged in prolonged campaign and hard marching, particularly with poor food and frequent conflict with the enemy. The real condition at the bottom of overtraining is still somewhat ob- scure, but in the light of recent inquiry certain possibilities are suggested by Darling as factors which may have much to do with its causation. The first and most obvious one is the condition of the heart. A great increase in size and strength is demanded of this organ, and it may easily happen that it is called upon for more work than it is able to do,' and that instead of establishing a compensatory hypertrophy it becomes dilated and weakened. A "broken-winded " athlete or soldier is probably one with a dilated, flabby heart. The second possible factor is the condition of nutrition. This is more difficult of demonstration than the first. The nutrition may be dis- turbed in two ways, either by an improper diet, in which the nutritive elements are not apportioned to the needs of the body, or by disturbed digestion, as a result of which the food taken into the body is not utilized. That both of these contingencies may occur has been sufficiently demon- strated. Further, as aheady stated, the influence of exhaustion of reserve fuel, in the form of fat and glycogen, in the production of overtraining, is undoubtedly of great importance. The third factor may be simple over- work. This is not so likely as the two preceding; for, when properly nourished, the capacity for work on the part of healthy young men is certainly much greater than that demanded in training. The peculiarity of severe training, however, is its concentration. It may be that the ex- cessive work accomplished in a brief space of time exhausts the muscles so that they do not recuperate before being caUed upon for a repetition of the work — ^that there is, so to speak, an accumulation of fatigue, and that this constitutes overtraining. The fourth factor which suggests itself is a nervous one, and this, while more intangible than the others, is unques- tionably important. In the present state of our knowledge it can be only surmised, not proved. It is well known that there is a nervous fatigue entirely distinct from muscular fatigue and resulting from prolonged anxiety, from monotony of work, and from numerous other causes. It may be that anxiety leads to a condition of nervous exhaustion, and that this nervous exhaustion contributes to overtraining. No one of these factors wiU. account for all cases of overtraining and probably more than one cause must be admitted. At any rate it is safe to suggest certain points which should be borne in mind in laying out any course of training. They are (1) not to throw too much work upon the muscles, and especially upon the heart, until they are strengthened by pre- 52 THEOEY AND PEACTICE OP MILITAEY HYGIENE. liminary work; (2) to watch, the nutrition carefully, and (3) to avoid nervous fatigue by providing a certain variety of exercise, and by not con- fining the attention too closely to the results to be attained. Proper Physical Proportions. — ^While the physically perfect man is a figment of the imagination, the following comparative measurements, as given by Blaikie, show the ideal proportionate development which physical training endeavors to produce in soldiers. (1) The neck, muscled arms and legs around the calves should measure the same. (2) The upper arms relaxed should measure two to two and one-half inches more than the forearm. (3) The circumference of the shoulder should be about four inches more than that of the neck. (4) The circumference of the shoulders should be about four raches more than that of the muscular chest inflated. (5) The difference between the expanded and unexpanded respiratory chest should be about four inches. (6) The muscular chest expanded should be eight to ten inches larger than the smallest natural waist. (7) The chest width should be about two and one-half inches more than the chest depth. (8) The largest hip measurement should be four to five inches larger than the smallest natural waist measurement. (9) The thigh should measure six or seven inches more than the calf. Development of Special Parts. — As sunmiarized by Maclaren, "where the activity is, there wUl be the development." Bearing this fact in mind, the determination of muscular growth becomes at once simplified and readily accomplished. While the exercises which bring into action any given set of muscles are very numerous, a few may here be given, which, on account of their simplicity and the fact that either inexpensive apparatus, or none at all, is required for their accomplishment, are practi- cally adapted to the needs of the' military service. A larger variety of movements, essential for the physical culture of the weak, dwarfed and undeveloped of civil life, are scarcely to be required in the case of the re- cruit, himself already free from blemish and selected under standards which ensure his general physical superiority to the class from which he is derived. The exercises may be conveniently arranged as follows : 1. To develop the calf of the leg {a) the seventeenth, exercise of the settipg-up drill is unsurpassed. To this may be added, (&) running on the toes, (c) jumping — both high and flat — and (d) hoppiog. The fourteenth and fifteenth exercises of the setting-up drill are also valuable. 2. To increase the size and power of the shin muscles (a) the thirteenth exercise of the setting-up drill is probably the best. This exercise may be supplemented by (5) balancing on one foot, holding the other clear of the .floor and then drawiog it up as nearly as possible to the front of its own ankle, (c) Walking on the heels serves the same purpose. 3. To develop the anterior muscles of the thigh {a) the fourteenth exercise of the setting-up driU may be employed. A more severe tax is (b) by extending one foot either front or rear and then stooping down whoUy on the other foot, (c) Jumping, either high or flat, is admirable THE DEVELOPMENT OE THE RECRUIT. 63 for the thighs ; as are also (d) fast walking and (e) runniQg. (/) Hopping, excellent for the calves, is hardly less so for the front of the thighs, (g) Cycling and (h) horse exercise also enlarge these important muscle'). 4. To develop the thigh posteriorly (a) the eleventh setting-up exercise may be employed, (b) Hill climbiag is excellent ; while (c) running with the foot thrown high behind is best of aU. 5. To add strength to the loins (a) the eighth, (6) the eleventh and (c) the twelfth setting-up exercises may be' employed, (d) Bending down, and touching the floor with light dumb-bells — ^the knees being kept rigid — is probably the best exercise for these muscles. 6. The abdominal muscles are well brought into action by (a) the eighth setting-up exercise ; (b) the eleventh and (c) twelfth exercises having a less powerful influence in this respect. The best method consists (d) in lying on the back and drawing the straightened legs upward until the vertical position is reached and then lowering them until horizontal. Another method consists (e) in taking the same recumbent position, keep- ing the legs down and drawing up the body until sitting erect, (f) Running implies great activity of these muscles. 7. To strengthen the sides of the waist (a) the ninth setting-up exercise may be employed. A better method than this, however, consists (b) in extending one hand vertically above the head, while the other is brought down against the thigh, the arms rapidly alternating in position. 8. To develop the trunk above the waist the (a) first, (b) second, (c) third, (d) fourth, (e) sixth and (/) seventh setting-up exercises are all ex- cellent and each should be briefly employed in its turn. For more severe exercise these motions may be carried out with light dumb-bells. 9. To enlarge and strengthen the front of the chest (a) the exercises given below for the development of the biceps and triceps wlU be of advantage. Of particular value in this connection is (5) the second setting- up exercise, (c) Using dumb-bells with the arms extended at right angles to the body, and moving them up or down for a foot or so, is one of the best exercises for the upper portion of the pectoral muscles. 10. In filling out the shoulders and upper back (a) the arms, hanging at the sides, may be carried backward and upward, keeping the arms parallel and straight at the elbows. They are held in position a moment and then allowed to drop slowly back to the sides. Light weights or dumb- bells may be advantageously used in the execution of this movement, (b) The second and (c) the fourth setting-up exercises are excellent for the development of this region. 11. To bring up the muscles of the front and side of the shoulder (a) the holding of weights at arms' length is excellent. The weight of the hands, as in boxing, or the sabre or foil, falls directly at this point, (b) With the elbows straightened and the arms held parallel the bells are raised vertically over the head and then returned to the original position, (c) Holding the bells at the side, they are raised behind as far as possible and then lowered as before. 12. To develop the neck (a) carry the head forward and back, and also move it laterally, (b) Resting on the head and heels — the so-called "wrestler's bridge " — is an admirable exercise for this purpose. 13. The triceps muscle is brought into action in (a) the first portion of 54 THEORY AND PRACTICE OF MILITARY HYGIENE. the seventh setting-up exercise. A better exercise, however, is (b) to push up light dumb-bells vertically above the head. A more severe test is (c) to stand facing a wall and about two feet from it. The hands are placed on the wall about three feet apart ; the body is allowed to fall slowly in until the chest nearly touches the wall and is then pushed back until the erect position is again assumed. 14. To enlarge the biceps (a) the use of light dumb-bells or other weights is desirable. Starting with these held at the sides, they should be raised slowly and steadily in front until they nearly touch the shoulder. The neck is held well back and the beUs are lowered slowly to the sides. (b) Picking up weights or (c) holding weights at arms' length are valuable exercises in this connection. 15. For the development of the forearm (a) the fifth setting-up exercise is admirable. It should, however, be assisted (b) by flexion and extension of the wrist and (c) by the motions of pronation and supination, preferably with light weights. 16. The development of the muscles of the hand is provided for (a) in the fifth setting-up exercise. For improving the grasp of the hand (6) the simple squeezing of a rubber ball, a wad of any elastic material, or even paper, will soon teU. 17. For the development of the lungs themselves deep breathing is essential; and, as this is induced by any active exertion, marked improve- ment wiU follow brisk general exercise irrespective of special physical training. Excellent lateral chest expansion foRows the use of the first and fifth setting-up exercises. ' To deepen the chest employ the eleventh setting-up exercise, or (c) hold the arms horizontally in front and slowly raise them to the vertical position. The head should be held high, prefer- ably even back of the vertical line. General Plan for Physical Development. — Maclaren suggests the following system of gymnastics as fitted to afford harmonious development. First : an introductory course of posturing and light exercise with dumb- bells and bar-bells. Second : leaping the horizontal bar, vaulting bar and horse. Third: parallel bars, swinging rings, ladder, horizontal bar and plank. Fourth : climbing the pole — fixed, slanting, turning — ropes, ros- ary and mast. A schedule for the varied instruction of a company where but little gymnastic apparatus is available, or only that which could be put up at any post, as given by Butts, i3 as follows : Lesson. Ten minutes drill. Ten minutes drill. Ten minutes drill. 1.... 2.... 3 Rifle drill Dumb-bells Calisthenics Rifle drill Rifle drill Calisthenics Indian clubs .... Dumb-bells Rifle drill Calisthenics .... Running and walking Hurdling and sprinting Wall scaling Calisthenics. Bar-bell. Medicine ball. 4.... 5.... 6.... 7 Long and high jumping Running and passing obstacles. Hurdling and sprinting Wall scaling Climbing ropes, planks, etc. Horizontal beams. Bar-bells. Medicine ball. 8.... 9.... 10 . Climbing ropes, planks, etc. . . . Long and high jumping Horizontal beams Coek-flght. Carrying wounded. Wall scaling. To the exercises as prescribed above by Butts may be advantageously THE DEVELOPMENT OF THE RECRUIT. 55 added wrestling (the most generally valuable of aU exercises), boxing, fencing, and broad-sword exercise, bayonet and sabre drill. Where such apparatus is available, the use of the chest weights and rowing machine wiU be found of the greatest advantage. At least once a week during the season field sports should be indulged in ; such general exercises as hurdling and running at the various distances being particularly encouraged. Where prizes are to be given they should not be awarded for excellence in any one sport or event, but should be reserved for the best all-around athletes — ^the men who excel under any conditions which may be imposed upon them. It should always be remem- bered that the athletic specialist is of but little advantage in the military service. For the use of the trained soldier there should be, in every garrison, walls for practice ia the escalade by mutual support, hurdles and ditches to leap, banks to jump off, and bars to vault. These exercises, at first practised without the equipment, should ultimately be done ia heavy marching order. The changes should be rung on these exercises and they should be performed at least two hours weekly. Whatever be the course of instruction employed, a carefully prepared scheme — possessing both the elements of pastime and instruction — should always be developed. Such a scheme should not, however, be of too military a character ; and set movement should be largely avoided, as being too mechanical and monotonous to be attractive to the soldier. Under any circumstances the men should be divided into squads according to proficiency, so that such exercises may be selected as will give the best results. One set may need strength, while another shows the awkward powers of the laborer and requires agility. Hartwell thus enumerates the four conditions which physical educa- tion must meet in order to be successful: 1. It must have a direct and large effect upon the health. It must build up vitality. The large muscular groups of the body, the muscles of the back, the waist, the chest, the thighs, must be made to contract with vigor a large number of times. It is through such vigorous contraction of these large groups that the heart is strengthened, the lungs are brought to their best condition of development, and the digestive system is stimulated to more perfect action. Upon the satisfactory working of these three systems health and vigor largely depend. 2. There should be that training which wOl confer skOI in handling the body. The hands, arms, and body should be trained to act with skill and activity. A high degree of co-ordination should be rendered easily possible. The muscles of the trunk and the nerve centres governing them must be brought into that condition of discipline which wiU. enable them to act with the greatest readiness and freedom. 3. There should be secured that control of the body which we call good carriage, graceful, vigorous action, not merely in walking, but in all of the positions and exercises which are required of the soldier. 4. The psychological elements — courage, coolness, self-control and self- reliance — should be prominently brought out. As summarized by Hyde: "That exercise is best which reaches the largest number and does most for the weakest men. That exercise is best 56 THEOEY AND PRACTICE OF MILITAEY HYGIENE. which makes the hardest work attractive. That exercise is best which most co-ordiaates body, mind, and will." Physical Training in Foreign Services. — In France, Germany and Austria a compulsory system of physical traiaing is in force in all educa- tional institutions, both civil and military, with resulting marked influence upon the national physical development. The soldier after his enrollment continues a course of physical training with which as a boy and youth he has aheady become familiar, and the main features of which still re- main the essentials in his military education. Among the schools of England, as in our own, no special gymnastic training is officially re- quired, the taking of proper exercise being left largely to the individual ; much to his physical disadvantage when compared with the corresponding classes of the countries just named, and to unnecessary detriment of the military service of which he may ultimately become a part. In most foreign services the physical training of the soldier begins immediately he joins, and is continued to the end of his service with the colors. There is no such thing as a man commencing a course of physical training and being taken away in the midst of it for military drill or target practice ; to return after a lengthy absence to begin again, having forgotten much that he may have been taught and lost much of the benefit he may have derived. Once started, his training continues systematically and progressively to the day he is passed into the "Eeserve," he getting the maximum of benefit without the waste of time, labor and expense. In 1842 the value of physical training for the military service was officially recognized in the German army, and schools were established for the education of instructors in this subject. The training in that army is at present comprehensive in scope, but particular importance is attached to practical and applied gymnastics, the men being continually exercised in them throughout their service. As illustrating the festimation in which gymnastic training is held in Germany it was said in a circular published in 1871: "It is acknowledged everywhere by soldiers and civilians that the astonishing accomplishments of our armies in the late war, especially their thorough discipline, exhibited in the most cheerful and self-sacrificing manner, their skill in overcoming natural and artificial obstacles in a hostile country, their courage and calmness in battle, the resolution with which they bore pain and privation, must, in large measure, be attributed to the gymnastic training of the rank and file." France has equalled Germany, and, if elaboration of exercise, number of apparatus and multiplication of detail is a criterion, she is even more advanced in physical traiaing. In France attempts were made in 1847 to establish physical training in the army, but no good results were arrived at owing to imperfect organization. In 1869 the Government issued a decree making gymnastics compulsory at aU schools, but the operation of this law was nullified by the war of 1870. At the termination of the war, however, France awoke to the necessity of cultivating a strong race of men and a large number of athletic societies were established. In 1878 the Government made physical training compulsory in aU schools, and since that time immense improvement has been made in the physical de- velopment of the French. The instruction of the recruit begins with calisthenics and gymnastics, at first without the use of weapons. It in- THE DEVELOPMENT OF THE KECBUIT. » 57 eludes the movements for suppling the arms, flexions of the body and lower extremities, and also movements of jumping. These exercises are afterward repeated with arms, and later with arms and the full equipment. FoUowing this traiaiag, a course in applied gymnastics is instituted, which include aU exercises which bear on the accomplishment of feats of a peculiarly military nature. A comprehensive and carefully prepared system of training has been laid down in the British service; the character of the exercises being officially stated to be "so arranged that while the most advanced course is sufficient to test the powers of the strongest the preliminary course can be performed without injury to the weakest frame." According to Woodhull, gymnastic drUl is required one and one-half hours daily in simple move- ments, the older soldiers having a more extensive course. This is augmented for the foot service by a one-hour running drill daily, the training beginning at the distance of three hundred yards, and ending with one thousand yards; moimted soldiers being given extra work in fencing and single stick. As in the various continental armies, swimming is taught at all stations where the facilities exist. Some of the gymnastic exercises are accompanied by music. Special schools have been established for the gynmastic instruction of officers and non-commissioned officers; and ex- cellent gymnasia, with simple though adequate appliances, are provided for all posts. It is officially prescribed that the exercises be not carried to the point of fatigue, and that they be varied sufficiently to avoid lack of interest. In Austria the highest importance is attached to the physical education of both soldiers and civilians, it being compulsory in schools for both classes; but as late as 1848 the educational spirit dominant in the country was absolutely hostile to it, and it was not until the year following their humiliating defeat by the Germans that a compulsory system of physical training was put in force in all educational institutions as well as the military service — since which time it has rapidly and steadily grown to great importance. In Eussia a system of physical training was not officially established until after the Crimean War, when on the termination of that campaign, so disastrous to Eussia, it was established in every military school and corps, and has been increased and improved ever since. All recruits are under instruction for four months, and in time of war for two months. The system is -pfogressive and commences with the simplest exercises, advancing by degress to applied gymnastics, to which great importance is attached. In Italy, Norway, Sweden, Denmark, and Switzerland systems all more or less similar obtain, and physical culture is looked upon as necessary as, and also as being an aid to, the mental and military education of the in- dividual. Physical Training in the United States Service. — The American soldier cannot be regarded as an athlete or even well-trained physically, lu time of peace the ordinary garrisons have been so small, and the work required of them so various, that there has been little lack of physical exercise in the sense of mere muscular exertion ; but there has been largely omitted from the military life that intelligent and comprehensive physical 58 THEORY AND PEACTICE OF MILITARY HYGIENE. instruction which is essential to the equable and physiological development of the body, As expressed by PiLcher: "While the medical department has devoted ample attention to the prevention of disease by the removal of threatening conditions it has almost entirely neglected prophylaxis by increasing the resistive power of the soldier himself. It is also true that the line has been equally unmindful of so potential an agency in securing efficiency in the soldier ; devoting centuries to the development of weapons of war, entirely regardless of the men who were to handle them. Having had a single object in view, the training of the soldier has been confined to the single direction of military exercise. This, having no break or variety of motion, becomes tiresome, is done in a perfunctory manner and failing in its hygienic function, leaves him overtrained in certain anatomical regions, expert only in specific muscular actions and generally but little better off physically than when he entered the service. " It should be con- sidered that if physical training has been found necessary for soldiers of European armies, all of them msn who have been compelled to undergo an extended preparatory training while at school, it must be . much more necessary for our men, recruited as they are from a population that has no such advantages. Physical training should not be merely tolerated — as has been too largely the case in our service — but should be officially prescribed rather than encouraged, and proper places and appliances provided for its execution. It should be carried out under orders from the War Department, since if physical training be left to the discretion of an indifferent commanding officer the exercises are apt to become both tedious and farcical. In char- acter and scope they should be regulated as carefully as drill and tactics ; ■ for if there be no definite requirements, no specific programme, no sufficient incentive to make of physical education the Same serious business as is the case with target practice or other purely military functions, the results must always be unsatisfactory. As expressed by General Miles : " The physical training can be made injurious to the enlisted man or of great benefit, depending much upon the care and attention of the company officers and the interest taken by the individual" — and to this might be added the necessity of intelligent medical supervision. Many zealous officers, largely unlearned in anatomy, physiology and hygiene, cannot appreciate the application of their govern- ing laws to the proper growth of the normal man ; and such, especially if lacking in experience, may illy direct or overtax the powers of the in- dividual. At present, also, the instructors — not always themselves trained athletes — are frequently changed during the physical education of a recruit, and the advantages of a systematic course of training are thus lost. Squads, too, are composed of the ignorant, the partially and the wholly-instructed — a condition which cannot fail to be detrimental to the welfare of each individual and of the whole. The authorized exercises should be rational and simple. The present tendency is rather to induce excellence in feats of agility and athletic sports than to develop the muscular system regularly by less interesting gymnastic training; but spectacular work should be discouraged, and the efforts limited to an honest endeavor to improve health, strength, endurance and muscular harmony. THE DEVELOPMENT OF THE EECKUIT. 59 The War Department authorities have for some time permitted the expenditure of post and company funds for fixtures and appliances for athletic sports; and, in 1889, when the establishment of canteens was authorized, official announcement was made that one of their objects was to afford the troops "the requisite facilities for gymnastic exercises — and other proper games." This plan, however, will always yield un- satisfactory results, and such an important factor in the military education should not be made dependent for its support upon meagre and infrequent allotments from unreliable sources. At each military station a suitable gymnasium should be provided and adequately equipped by the Quarter- master's Department — the apparatus being not necessarily either elaborate or costly. If possible, the gymnasium should be so planned or located as to render the shower baths available for use after exercising. At posts where much of the physical training must be done under cover the issue of proper gymnasium shoes to troops should be authorized. A cinder track, for use in connection with athletic sports, is desirable although not absolutely essential. Schools of Instruction. — Special schools for the training of instruc- tors in gymnastics and physical exercise are maintained in all the more iinportant foreign military services. In the German army particularly, great value is attached to physical training. All officers are required to be proficient teachers of certain designated exercises ; while one officer and several non-commissioned officers are yearly detached from each regiment and sent to large training-schools for an extended course of instruction. The central establishment is in Berlin, a section being set apart for the instruction of officers. In the British service special classes have been instituted at Aldershot and the Curragh for the training of non-commis- sioned officers as instructors in gymnastics. The French training-school at Joinville-sur-Pont graduates yearly from six hundred to eight hundred in- structors for the army. These graduates are non-commissioned officers drawn from the several branches of the service. They are given a course of six months' training calculated to produce general physical development, and are also exercised in applied gymnastics, in practice-marching and in the construction of fortifications and entrenchments. For the greater efficiency of our own army it is desirable that schools of the above character be established at suitable points, preferably as ad- juncts to the present service schools at Fort Leavenworth and Fort Monroe. In addition to the student officers already detailed in attendance on the general course of instruction, of which the work in physical training should be a part, each regiment should be required to send yearly two non- commissioned officers to this school, thus providing a sufficient number of officers and non-commissioned officers capable of competently un- dertaking the physical training of the men. II. CONSIDERATION OF SPECIAL EXERCISES. Attention. — The position of attention is the basis of all martial bear- ing, showing its effects most conspicuously when the man is in motion. While not in general looked upon in the light of an exercise its mainten- 60 THEOEY AND PRACTICE OF MILITARY HYGIENE. ance nevertheless implies constant and symmetrical muscular action, which, when protracted, becomes one of the most severe tests of endur- ance which can be required of the soldier. When troops remain steadfast for a considerable time, as during a review, and particularly when equipped in heavy marching order, the constrained position and immobility may combine with the weight of the equipment to produce faintness and syncope. Manual of Arms. — The manual of arms, while bringing into action the muscles of the arms and chest, is, when considered as a means of ex- ercise, both inadequate in character and injurious in effect. The move- ments are not sufficiently comprehensive, and then- influence upon the body is such as to render it unsymmetrical, often inducing a marked drooping of the right shoulder and in some instances, in immature recruits, manifesting a tendency toward the production of lateral curvature of the spine. To combat this unequal development a special course of training becomes necessary, and this should be carried on concurrently with the driLL of the recruit. The manual of arms does little or nothing to strengthen the soldier, but as regards certain muscles rather the reverse. These movements, limited in number as they are, requii-e comparatively little skiU in their execution when once acquired, and are performed automatically to a greater or less degree. Experience has shown that the lowest class of men learn these movements and acquire a degree J of precision comparing favorably with those more highly endowed, and with practically no beneficial physical results. In this connection it may be emphasized that sound health and generally increased strength are not obtained through use and development of special muscles in the performance of specific acts, but in the synchron- ous and harmonious development of all muscles of the body. The constraint and discipline accompanying the execution of the manual of arms become in a sense mechanical — ^thus rendering it of more advantage as a mental and moral exercise than as a means of physical traiaing. Setting-TJp Exercises. — While every movement of the manual of » arms and every evolution in driU or marching has its effect upon the muscular system, it is an error to presume that these alone are sufficient for bringing about and maintaining thorough physical efficiency. Not • only by themselves are they inadequate for the maintenance of harmonious development, but, as already noted, they markedly tend to the origination and accentuation of bodily asymmetry. To remedy their serious deficien- cies and defects, and to correct the vicious attitudes and unequal muscular growth imposed by various phases of military duty, the setting-up driU, so far as it goes, is most efficient. For the proper development of aU portions of the muscular system, however, it is not sufficiently comprehensive in its scope, and hence might be advantageously amplified by the addition of certain of the simple movements and exercises detailed in the previous section. From a more spiritual aspect setting-up exercise does away with much of the heaviness and gaucherie noted in new recruits. Straightening up their bodies to a position of grace and manly erectness, it also insensibly communicates a similar uplifting tendency t(j the mind — awakening the THE DEVELOPMENT OF THE RECRUIT. 61 intellect, sharpening the wit, and keeping consciousness on the alert by its innumerable demands on the mind for obedience to new orders. Finally, it trains the body to work m harmony and conjointly with the miad — an operation frequently of burdensome performance by recruits. Infantry tactics state that " in order to retain a proper set-up and to keep the muscles supple, all soldiers in garrison should be frequently practised in the following exercises. The arm, hand, trunk, leg, and foot exercises should be alternated, the driU interrupted by frequent rests and varied by instruction in the facings, marchings, etc. While exercising one part of the body care should be taken that the other parts remain quiet, as far as the conformation of the body wiQ allow." First Exercise. — (1) Arm, (2) exercise, (3) head, (4) up, (5) down, (6) raise. At the command exereise, raise the arms laterally until hori- zontal, palms upward. Head : Raise the arms ia a circular direction over the head, tips of fingers touching top of cap over the forehead, backs of fingers in contact their fuU length, thumbs pointing to the rear, elbows pressed back. Up : Extend the arms upward their full length, palms touching. Down : Force them obliquely back and gradually let them fall by the sides. Raise : Raise the arms laterally as prescribed for the second command. , Second Exercise. — (1) Arm, (2) exercise, (3) front, (4) rear. At the command exercise, raise the arms laterally as in the first exercise. Front : Swing the arms extended horizontally to the front, palms touching, heels on the ground. Bear : Swing the arms extended, well to the rear, in- clining them slightly downward, raising the body upon the toes. Third Exercise. — (1) Arm, (2) exercise, (3) circle. At the command exercise, raise the arms laterally, as in the first exercise. Circle : Slowly describe a small circle with each arm, upward and backward, from front to rear ; the arms not passiug in front of the line of the breast. Fourth Exercise. — (1) Arm, (2) exercise, (3) shoulder, (4) front, (5) rear. At the command exercise, raise the arms laterally as in the first exercise. Shoulder : Place the tips of the fingers lightly on the top of the shoulders, keeping upper arm horizontal. Front : Force the elbows to the front. Bear : Force the elbows back as far as possible. Fifth Exercise. — (1) Hand, (2) exercise, (3) close, (4) open. At the command exercise, raise the arms laterally as in the first exercise. Close : Close the hands with force. Open : Open the hands quickly, spreading the fingers and thumbs apart as much as possible. Sixth Exercise. — (1) Forearms vertical, (2) raise, (3) up, (4) down. At the command raise, raise the forearms until nearly vertical, fingers extended and joined, palms toward each other. Up : Thrust forward with force, extending the arms to their full length. Down : Force the arms obliquely back and gradually let them fall by the sides. Seventh Exercise. — (1) Forearms horizontal, (2) raise, (3) front, (4) rear. At the command raise, raise the forearms to the front until hori- zontal, elbows forced back, hands tightly closed, backs down. Front: Thrust the arms forcibly to the front, turning the backs of the hands up, arms horizontal. Bear : Bring arms back quickly to the first position, forcing elbows and shoulders to the rear. Eighth Exercise. — (1) Trunk, (2) exercise, (3) down, (4) back. At the 62 THEORY AND PRACTICE OE MILITARY HYGIENE. com.Taa.nd* exercise, raise the hands and place them on the hips, fingers to the rear, thumbs to the front, elbows pressed back. Down : Bend the trunk forward at the hips as far as possible. Back : Raise and bend the trunk to the rear as far as possible. Execute both motions slowly, without bending the knees. Ninth Exercise. — (1) Trunk, (2) exercise, (3) right, (4) left. At the command exercise place the hands on the hips as in the preceding exer- cise. Bight : Bend the trunk to the right without raising either heel. Left: Bend the trunk similarly to the left, executing both motions slowly. Tenth Exercise. — (1) Trunk, (2) exercise, (3) circle right (or left). At the command exercise, place the Imnds on the hips as in the eighth exercise. Ci^'cle right : Bend the trunk to the right as ia the ninth ex- ercise ; turn the trunk to the rear as in the eighth exercise, turn the trimk to the left and bend it to the left, as in the ninth exercise ; tvim the trunk to the front and bend forward, as in the eighth exercise. Eleventh Exercise. — (1) Arms vertical, palms to the front, (2) raise, (3) down, (4) up. At the command raise, raise the arms from the sides, extended to their full length, till the hands meet above the head, palms to the front, fingers pointed upward, thumbs locked, right thumb in front, shoulders pressed back. Down : Bend over till the hands, if possible, touch the ground, keeping arms and knees straight. Up : Straighten the body and swing the arms, extended to the vertical position. Twelfth Exercise. — (1) Arms_ forward, palms down, (2) raise, (3) doivn, (4) u,p. At the command raise, raise the arms to the front, extended their full length, till the hands are in front and at the height of the shoulders, palms down, fingers extended and joined, thumbs under fore- fingers. Down : Bend the trunk forward at the hips as far as possible and swing the arms backward, knees and arms straight. Up : Straighten the trunk and swiag the arms to the upward position. Thirteenth Exercise. — (1) Leg, (2) exercise, (3) half lend, (4) down, (5) up. At the command exercise, place the hands on the hips, as in the eighth exercise. Down : Lower the body, separating the knees and bend- ing them as much as possible, heels on the ground, head and trunk erect. Up : Raise the body, straightening and closing the knees. Fourteenth Exercise. — (1) Leg, (2) exercise, (3) full lend, (4) down, (5) up. At the command exercise, place the hands on the hips as in the eighth exercise. Down : Lower the body, separating the knees and bend- iQg them as much as possible, head and trunk erect, heels raised, weight of body resting on the balls of the feet. Up : Raise the body, straighten- ing and closiDg the knees, and lower the heels to the ground. Fifteenth Exercise. — (1) Leg, (2) exercise, (3) left {or right), (4=) for- ward, (5) rear, or ground. At the command exercise, place the hands on the hips as in the eighth exercise. Forward : Move the left foot to the front, knee straight, so as to advance the foot about fifteen inches, toe turned out, solp nearly horizontal, body balanced on right foot. Hear : Move the leg to the rear, knee straight, toe on a line with the right heel, sole nearly horizontal. Wlien the recruit has learned to balance himself the command forward is followed by grotmd. Throw the weight of the body forward by rising on the ball of the right foot, advance and THE DEVELOPMENT OF THE EECEUIT. 63 plant the left, left heel thirty inches from the right, and advance the right leg quickly to the position oi forward. Sixteenth Exercise. — (1) Leg, (2) exercise, (3) up. At the command exercise, place the hands on the hips as in the eighth exercise. IJp : Raise the left leg to the front, bending and elevating the knee as much as possible, leg from knee to instep vertical, toe depressed. Up : Eeplace the left foot and raise the right leg as prescribed for the left. Seventeenth Exercise. — (1) Foot, (2) exercise, (3) up, (4) down. At the command exercise, place j_the hands on the hips as in the eighth exercise. Up : Eaise the body upon the toes, knees straight, heels together. Down : Lower the heels slowly to the ground. These exercises, though simple, are fatiguing; and the various groups of muscles are best brought into action for brief periods only. The ex- ercises in general, and particularly any one movement, should never be carried to excess, since under such circumstances, especially when the heart is irritable, faintness is readUy induced in untrained recruits. Particu- larly is this true of the third exercise. Fencing. — This exercise is of particular value in producing chest de- velopment. It brings into play all the muscles of the body and ensures agility and soundness of wind as well as decision of character and rapid co-ordination. It has the disadvantage, if used to excess, of inducing an exaggerated development of the side holding the foil, together with scoliosis, the concavity of the spine corresponding with the sword arm. On the same side the shoulder is dropped and the chest flattened. These faults, however, may be avoided by fencing with each arm alternately. To avoid injuries the mask should be so rounded that the fod. can scarcely strike perpendicularly; while the mesh of the mask itself should be small, as also the button on the foil. Due care should be taken to protect the hand of the sword arm from injury — but constant exercise in fencing tends to produce contraction of the fingers. Both the faults and advantages of fencing exist in less degree in sabre exercise. Bayonet Exercise. — The primary object of bayonet drdl is to render the soldier quick and proficient in handling his piece, but it also serves as a most valuable physical exercise, expertness depending largely on quick- ness and accuracy of motion. Eleven movements are laid down in tactics ; but the number is not restricted, the addition or selection of other exercises being -left to the discretion and ingenuity of instructors. This drdl supples the soldier,-gives firmness of footing, increases muscular strength and removes awkwardness. It has, however, the general fault of all purely military exercises in that it favors unilateral development. Target Practice. — This is important as a form of exercise. It has the advantage of being carried on in the open air; and constitutes, with its varying positions and movements, a species of gymnastics requiriag for its performance the ready co-operation of vision, muscles and nerves, checking each shot with the immediate result. It is not, however, with- out drawbacks. When smokeless powder is used, and the shooting is done against the wind, the fumes from its combustion, inhaled by the marksman, often induce cerebral congestion and severe headache. At the longer ranges, particularly if the sun be high and heat waves induce refrac- tion, eye strain is frequently developed. Banister states that the latter 64 THEORY AND PEACTICE 0F_^M1LITAEY HYGIENE. affection is diminished in frequency, and that better scores are made, if the body of the target be black and the bulls-eye and riags be buff. This obviates the reflection of light, and at the same time produces a greater contrast between the color of the target and the face of the landscape. He also recommends that the prone position be the only one allowed ia recumbent |_firiag and that the side and back positions be excluded, as causing congestion of the intra-ocular tissues by compression of the blood vessels of the neck. In small-arms practice the markers are exposed to the dangers of gun- shot if due precautions for their safety are not carefully observed, and the same applies also ia less degree to the marksmen themselves. In artillery practice the atmospheric vibrations often result in injury to the auditory apparatus. During the recent Anglo-Boer war, MuUer found marked changes in the auditory apparatus in forty-four out of ninety-six soldiers examiaed before and after a battle, whUe many of the artillerymen were made partially deaf or suffered from buzzing in the ears. To avoid pos- sible rupture of the tympanum, hemorrhages from the eyes and ears, deafness and subjective noises, the artillerymen should stand well behind the piece and habitually open the mouth at the moment of firing to equalize the air pressure on both sides of the tympanum. The use of cotton wadding in the ears, to break the force of the atmospheric waves, is always advisable. Leques noted that injuries to the tympanum became much less frequent after breech-loading ordnance was adopted ; on the other hand the use of nitro and smokeless powders appears to favor them. Practice Marches. — Marchiag is the most important of military exercises. It has been laid down as an axiom that the soldier who cannot shoot is useless and an incumbrance to his battalion, and incontestably the same might be said with an even greater degree of truth as regards the soldier who cannot march; for whereas the former may conceivably find himself in a position where accuracy of aim is unnecessary, the man unable to keep up with his comrades is not only an incumbrance but be- comes in an enemy's country a positive source of danger. Not only should troops be able to march rapidly, but they should be able to cover a con- siderable distance in full campaign order. It is also a desideratum that they should do this without undue fatigue ; and that not only should they be able to take part in an engagement, but should, in the event of necessity, have sufficient residual energy to take part in a pursuit. Napoleon has been credited with the dictum that the secret of success in war lies in being able to march ten leagues, fight a battle, and march ten leagues afterward. If this was true of his day, it is even truer of our own. To enable the recruit to fulfill the above requirements properly it is evident that careful training is necessary. According to Austin, of the defectively trained British troops in the field during the annual manoeuvres of 1895, a large number were found unable to sustain the task assigned them; and of one division, in a single day, eight hundred and thirty-five found it necessary to fall out. Since that time British regulations ex- plicitly provide that practice marches are to be progressive, beginning with nine and gradually increasing to sixteen miles. The training culminates annually with a six days' march during which the battalion is required to cover one hundred miles. In the practice marches of the French army the THE DEVELOPMENT OE THE EECEUIT. 65 recniit commences at the distance of 16 kilometers, and this is gradually increased to 30 kilometers. Finally he is given four successive days of marching under the fuU equipment, the distances being 22, 24, 26, and 28 kilometers. With the French recruit, after some traioing, roads are aban- doned and the command marched over open country. The course of train- ing in vogue in the German and Eussian armies is similar to that of the French. In our own service no special regulations as to this training ex- ist ; in this respect, as in others, too much being left to the discretion of the local commanding officer. Troops are expected to make a practice march of mild character aod not too long duration, annually ; but there are no requirements as to the course of training which properly leads' up to such marching. This method is obviously faulty, and it is certainly unfortu- nate that the question of the systematic training of the soldier in this most important part of the military curriculum has not received more careful at- tention at the hands of the authorities. It cannot be said that free and graceful carriage, one of the essentials of correct physical training, is brought about by exercise in marching. In this drill the man is taught to march upright and stiffly, and look straight to the front. Every movement is constrained, and natural motion of the trunk or upper limbs is denied, thus stopping the action of muscles necessary for their development — and this at a period in the career of the soldier when every effort should be used for such development. Without correcting exercise, the individual undoubtedly acquires an accuracy of step and correct alignment in marching, but existing physical defects are unremedied and some are exaggerated. The effect of marching, when well regulated, is, as might be expected, unquestionably beneficial to the gen- eral health of the soldier. He gains in weight, the muscles become firmer and well developed, the face becomes ruddy and free from all signs of an- aemia. When marching is injurious the effect is found to be precisely the reverse : there are loss of weight, muscular flabbiness, anaemia, and a hag- gard, drawn appearance. The several phases of marching, apart from its uses as a means of instruction or exercise, are fully discussed in the next chapter. Running Drill. — Short drills in running are desirable from a military standpoint as well as excellent as a gymnastic exercise. They should not, however, be given too frequently, should commence with very short dis- tances, and even after very long practice should never exceed ten or fifteen minutes' duration. Drills at the double will first be without arms or accoutrements. After some practice, the armament, canteen and haver- sack may be added, but nmning with the full field equipment should at no time be indulged in. Commencing slowly, the pace should be increased to the middle of the run and then gradually decreased. The men should run entirely on the ball of the foot, striking the ground lightly, since running on the flat foot js- both fatiguing and awkward and on rough ground sprained ankles frequently result. Men showing any evidences of cardiac weakness should never be allowed to run. In this drill recruits should be encouraged to fall out at wiU, for a heart may very easily be irreparably overstrained, and an exercise intended to strengthen the man may ruin him for life. Even when permitted to fall out the overtaxed soldier wiU frequently endeavor to complete his task ; being spurred on by a desire to excel, to hide his weakness and to escape the banter of his 5 66 THEOEY AND PEACTICE OF MILITAKY HYGIENE. comrades. Hence the instructor should observe the men carefully, and be alive to the first symptoms of cardiac and respiratory embarrassment, as well as those of actual exhaustion. Instruction in double time is given the importance it deserves in various foreign armies. In the English service the regulations prescribe a running drill, in addition to the general physical training, for all infantry regiments ; it being intended that each man should ultimately be able to run one thousand yards without being too disturbed to use the bayonet, if it should be necessary. In the French army, running drill is given with and without the fuU equipment, is limited to two periods weekly, and the distance traversed must not exceed 120 meters. The distances prescribed for training are 60, 80, 100 and 120 meters respectively. Equitation. — This is the most important exercise of the mounted service. It brings into use certain previously undeveloped muscles of th^ leg and thigh, increases the appetite, promotes assimilation of food and mechanically aids the action of the intestines. Horse exercise is produc- tive of hemorrhoids and frequently induces hernia. It has been accused of causing varicocele, atrophy of the testicles and impotence, but these claims have scarcely been substantiated. Excoriations from riding are somewhat common in recruits but are of less importance than blistered feet in the case of the infantryman, and are also much less frequent.- To prevent such abrasions the painful spots should be washed and greased, while the drawers should be clean, soft, and well fitting. Furuncles are quite common among mounted troops. They usually occur on the buttocks, through pressure and irritation by unclean and sweaty clothing. When the pustules break, the pus and contained micro-organisms are frequently rubbed into other parts of the skin, thus forming new points of infection. On account of the uncleanly duties which the mounted soldier is re- quired to perform frequently, he must watch with care his bodily cleanli- ness, and washing after returning from stables, together with frequent bathing of the person, should be the rule. Work in the riding-hall is much less healthy than when carried out ia the open air. The atmosphere of the riding-hall is charged with a fine dust composed chiefly of microscopical splinters of wood, dried fecal matter, urine, and bacteria ; and this, when inhaled, is both irritant and dangerous. Since some maladies of the horse can be transmitted to man, all sick animals should be promptly isolated, and the equipments thoroughly dis- infected. Such men as have charge of sick horses should change their outer clothes and wash themselves well with soap and a disiufectant solu- tion after performing their duties and before returning to barracks. Natation. — ^As a military accomplishment, and apart from its hygienic advantages, all soldiers should be taught swimming; since they are thus rendered independent in case of accident or when it becomes necessary to cross a deep water-course duriag action. In every station near a suitable body of water, exercises in natation should be instituted during the proper season. Swimming combines the tonic and cleansing effect of the cold bath with general muscular exercise, without the disadvantage of being accom- panied by heat and perspiration. It should not be required in water hav- ing a lower temperature than 65° to 70° F., nor should it immediately THE DEVELOPMENT OF THE RECRUIT. 67 follow eating or severe exercise. Soldiers en route to the bathing-place should inarch slowly and not arrive sweaty ; although if men swim or exercise vigorously and not merely bathe and paddle in the water, there is no harm ia goinig into the water while moderately perspiriag. Colds are caught by standing undressed waiting to cool off, and no time should usually be lost in wetting the head and then entering the water. Under ordinary conditions, remaining in the water more than half an hour is in- advisable, and under any circumstances the exercise should be concluded on the slightest feeling of chilliness. Most persons unable to swim do not take sufficient exercise, especially if the water be cool, and such are prone to chill the body by sitting or standing on the bank, undressed, after having been in the water. The exercise should be supervised by an officer, assisted by the best swimmers of the command, and these should require the maintenance of constant activity and effort on the part of aU. Since swimming is a source of danger, instruction in the art requires careful surveillance, while the bathing-place should be carefully explored and the limits of safety for non-swimmers sounded out. In anticipation of possible asphyxiation by submersion, certain individuals of the command should always be proficient in the methods employed for the restoration of the apparently drowned, including Sylvester's method of artificial respira- tion and Laborde's tongue traction. Bathing is somewhat liable to in- duce ear trouble, and individuals so affected should not be allowed to participate in this exercise. The men should be cautioned against swim- ming under water on account of danger to the hearing, and on coming out should be instructed to incline the head to enable the water to escape from the ears. Certain individuals will often present a severe erythema as a result of cold bathing, and such should be excused by the medical officer, who should also fix the time and duration of the bath. Gymnasium Exercise. — Infantry tactics prescribe that where there is a regular system of gynmastic instruction it may replace the setting-up exercises for well-trained soldiers ; it being recognized that with the latter movements it is impossible to obtain such muscular development and control as foUows the intelligent use of gymnastics. E:^rcise in the open air is always preferable to that indoors ; but the gynmasium is the only place where every muscle can be most readily exercised, and has the great advantage of being available when drill and other military duties have to be suspended on account of inclement weather. Although a well-equipped gymnasium is naturally desirable, yet its main advantages for the develop- ment of the recruit may be obtained where a large building is available, and at the expense of but a trifling outlay for dumb-bells, Indian clubs, and carpenter work. If to the kinds of apparatus just named, the parallel bars, vaulting horse, rings, hanging rope, horizontal bar, spring- board, and chest weights be added, the outfitting of the military gymnasium becomes practically complete, and the further multiplication of apparatus may be regarded as an unnecessary refinement. A few simple, well-select- ed exercises with these appliances, thoroughly carried out, leave little to be desired. The men must bg taught how to exercise and use the apparatus ; since if not started in the light way they are liable to stand around helpless, imagining that as they cannot turn handsprings or perform other showy 68 THEORY AND PRACTICE OF MILITARY HYGIENE. feats there is nothing left for them to do. Energy and life should instilled into the drOl, and much better results wiU be obtained if iastruc- tion be given more by example than verbal direction. For this reason the delegation of the gymnastic driUs to younger officers is highly desir- able. Work in the gymnasium should be used to supplement the settiag-up exercises, and not to their exclusion. General development should be aimed at rather than the enlargement of any special group of muscles — a proceeding which, for military purposes, is of little or no value. The lighter and simpler exercises should be the compulsory ones, but encourage- ment should be extended to those men who show special aptitude for more difficult gymnastics. A few skilled gymnasts and athletes serve an ex- cellent purpose in a military command, since they are of use not only as instructors but also raise the standard to which the average man endeavors to conform. It should never be lost sight of, however, that in the military service the, mass must be trained — ^not the individual athletes. As a general rule, light gynmastics develop the muscles more uniformly and increase the capacity of the lungs much better than do acrobatic ex- ercises. After a certain amoimt of limg power and endurance has been obtained, it is only following the heavier work that frequent rests wiU be required ; since the exercises may be so varied that one part of the body can be rested while another is beiag exercised. When properly conducted the gymnastic work cannot fail to be attrac- tive, and the men wlU look forward to this feature of their life as a pleasure rather than an arduous duty, and as a welcome break in the monotony of the tactical drOls. Men with hernia and a few old soldiers who, by reason of age or in- firmity, have lost their agility, to whom the gymnastic exercise would be of no benefit, should be excused altogether from the driU. Such men as have largely lost their suppleness of joints but are still fit for active service should be required to fall out before each drOl and, under the charge of an instructor, be given a few minutes of light and entertaining exercise. Wherever praibicable there should be five drUls weekly, each drOl to be of at least thirty to forty-five minutes' duration. Applied Gymnastics. — Following a general course of physical train- ing, the French and Germans — and to some extent the English — accustom their troops to the overcoming of such obstacles as may often be encoun- tered in actual warfare. These exercises, known as "applied gymnastics," are practised first m light garb and without encumbrance, the soldier being gradually worked up to executing the movements under arms and with the full field equipment. The practical character and comprehensiveness of these exercises is well shown in the following description of the conditions under which the work is reported as being now carried on in the German service : " The course was U-shape, one hundred and ninety-five paces long and eighteen feet broad; the obstructions being arranged in the following order : " 1. A ditch, six feet wide, for the running jump. " 2. A mound of earth, three feet high and four feet wide, for the high jump. " 3. A ditch, twelve feet wide, for the broad jump. THE DEVELOPMENT OF THE EECRUIT. 69 " 4. A mound, six feet high and ten feet wide at the base, on the edge of a ditch twelve feet wide, for the ' deep leap.' "5. A board fence, five feet high, to be vaulted over. " 6. An escaladiQg stage, twelve feet high and six feet wide at the top, to be climbed by ladders, ropes, or poles, and jumped or dropped from. " 7. A ditch, ten feet deep and nine feet wide, bridged by a shaky beam and with an escarpment wall rising four feet above the hither «edge of the ditch. "8. A palisade, seven feet high, built of sharpened planks. " 9. A glacis. "A section of twelve men in three ranks of four each, with muskets, side arms, and knapsacks, habitually made the entire course, from end to end, in three to three and one-half minutes. Without weapons or knap- sacks, four men usually covered the course in sixty to seventy seconds ; and a few individuals were able to surmount the obstacles in forty-five seconds." Of the advantages occurring from such exercises Mutel says: "The soldier well trained in (applied) gymnastics knows how to jump consider- able heights, with or without his arms. He is able to cross streams or precipices with the trunk of a tree for a bridge and can pass over walls, ditches, or ravines, aided or not by such instruments as may be available, either with free hands or carrying a burden. He is accustomed to the escalade with or without the use of the ladder or knotted rope ; to climb to the top of trees and to descend readily ; to carry weights with address and security without bodily suffering or inconvenience, and to transport the wounded." In our service but little work of this character has been done in spite of its obviously great practical advantages. Through the efforts of Butts a few soldiers have lately been trained in the escalade and kindred exer- cises, but the work has unfortunately been looked upon as spectacular rather than as possessed of actual military value. Besides greatly conduc- ing to general efficiency and a sound bodily development, such a system of training would in a short time disclose the latent defects of physically imperfect individuals and result in their early elimioation from the service to which they are certain to be but a useless expense and encumbrance. It is much to be hoped that a course of exercises of this character may be officially incorporated into the military curriculum. Guard Duty. — ^Whether in camp, garrison, or on picket, and particu- larly when superadded to the fatigue of the march, on accoimt of the responsibility and vigilance which it imposes and the loss of sleep which it entails, guard duty is the most exacting and wearing that befalls the soldier. Ordinarily, guards' are reKeved every twenty-four hours, during which period the soldier may remove neither his "clothing nor accoutrements ; while he is on post and alert for two hours, with an interval of four hours' rest, four times during the tour. While under ordinary conditions this plan is not seriously olijectionable, dining periods of severe cold or great heat the sentinels should be changed more frequently or else the system of nmning-guards instituted. In the latter case the whole period is so divided that any particular soldier goes on but once in his tour or once during the night, and is able to rest during the remainder of the time. The guard must be larger than usual in order not to keep one man on post 70 THEOEY AND PRACTICE OF MILITARY HYGIENE. too long a time, but the compensation lies in the uninterrupted rest before and afterward. As sufficient sleep is indispensable, so its loss is followed by a degree of lassitude and discomfort amounting in many to actual suffering, especially in the case of recruits; and there is no doubt but that deprivation of accustomed rest is a potent factor in the production of a lowered resistance through which invasion by disease is favored. While young soldiers must necessarily take their share of guard duty, their tours should preferably not be in the 'first hours of the night, when the mature are wakeful and the young are disposed to sleep. Under this plan the older men wiU also receive their rest at a time when nature most prompts them to seek it. In war, night guard is very frequent, and rest must be completely subordinated to the necessity of guarding against surprise — ^this usually occurring at a time when the fatigues of campaign are greatest. In addition to the inclemencies of the weather, sentinels are unduly exposed to infection by disease, particularly that of a malarial nature. If hard-tack and a bowl of hot coffee be served out to the men just before going on post late at night — and this can usually be arranged — it is of decided advantage in preventing sickness. Guards in a dis- tinctly malarial region should be given five grains of quiaine at retreat, and should be required to wear flannel next the skin. Due care should be taken that the clothing worn should be suited to the duty and weather. The custom prevailing in many European countries of having the sentries belonging to the regiments of the guards posted in fuU dress uniform is a useless sacrifice of the hygienic to the aesthetic. It is the nights on guard ia all kinds of weather and with heavy re- sponsibility which break men down most rapidly. A tour of guard duty for a seasoned soldier should not occur oftener than once in five days, nor for a recruit oftener than once a week — and the longer the interval the better for the health. Too frequent guard duty is a potent factor in increasing desertions. Other Exercises. — Soldiers of all branches of the service, especially of the engineers and artillery, should often be exercised in the throwing up of entrenchments, instructed in the buLlding of roads, construction of mines, and similar duties. This kind of work, done in the open air, is very salutary if it be not carried to the poiat of extreme fatigue. In campaign, however, the work of fortifying becomes both laborious and dangerous, and it involves great exposure to fatigue associated with the action of heat or cold. The opening of the ground in a malarial country offers dangers which are to be palliated by the prophylactic use of quinine, choice of hours for the work and attention to the location of the camp during the night. Skating affords excellent exercise, but is usually considered rather in the light of a pastime. In Holland and to some extent in Eussia, how- ever, the troops are taught to drill and manoeuvre on skates. Snow-shoeing is valuable, and is included m the military training in the armies of Norway, Sweden, Austria and Eussia. Athletic Sports. — These, through the spirit of competition which they arouse, are a powerful factor in stimulating interest in physical exercise and do much to render even the hardest work attractive. Many sports, however, call for an irregular physical development; especial THE DEVELOPMENT OF THE KECEUIT. 71 proficiency requiring that certain muscles be cultivated to the exclusion of others. This class of exercises should not be encouraged in the military service, and hence such exercises as the pole vault or throwing the shot and hammer are undesirable. The tug of war, so popular among soldiers, is liable to induce heart strain, and is possessed of no particular advantage in the military education. Long-distance running — as in "hare and hounds " — much praised by some, is not to be advised in the physical train- ing of the soldier. Williams found that of eleven trained athletes who par- ticipated in a cross country nm aU had lost weight, one as much as six poimds, and aU were exhausted, cyanotic, and presented weak cardiac action. Boxing and wrestling are admirable, the latter being the best of aU single exercises. Besides developing every muscle in the body the last two exer- cises impart confidence and self-reliance, and may often be of direct value in the exigencies of military service. Interest in baseball, football and other manly games should be stimu- lated in every manner ; and as many men as possible should be encouraged to participate in the training. Football, above all other sports, is the game of the soldier, since it develops strength, agUity, coolness, fearlessness, and determination, all subordinated to a leading mind in perfect discipline. Beyer found that the total strength of seventeen naval cadets, averaging nineteen and one-half years of age, and having an average height of 1.765 meters, was increased, in one month of practice at football, no less than 17.15 per cent. — or nearly by one-fifth. When properly played by ade- quately trained men, this game is largely free from the danger of severe ac- cidents. Strains often occur and bruises are common ; but the severe and sometimes fatal injiuries which are recorded are received practically only by the untrained and by immature and undeveloped boys. A recent in- vestigation of football, as played at the three great universities of Yale, Harvard, and Princeton, showed that in ten years less than a dozen broken bones had been incurred at those institutions. This showing emphasizes the fact that careful preliminary training, consisting of running, dodging, tackling, and, above all, of learning how to fall oh the ball and to be thrown so as to receive no injury, practically eliminates aU valid objec- tions to this admirable exercise for the soldier. It may be remarked, in passing, that the athletic spirit now so much cultivated in colleges, athletic clubs, and similar organizations is of peculiar value in connection with the military strength of the nation, in that it does much to render available, in case of an emergency, a large number of young men trained in bodily exercise and readily receptive of military instruction. III. MENTAL AND MORAL EDTTCATION. To the training of the body should be joined that of the mind, to in- culcate the spirit of discipline in the soldier. Eaw or ill-disciplined troops are always sickly as a result of their own ignorance and indiscretion, and hence the moral training has an important bearing on hygienic results. The soldier should be of manly character, willing, brave, steadfast, zealous, enthusiastic, of good humor, and possessed of initiative. At aU 72 THEORY AND PRACTICE OF MILITARY HYGIENE, times there should be exacted complete subordination, outward manifesta- tion of respect to superiors, precision and correctness iu exercises, and that temporary effacement of the personality which makes the man in the ranks a part of an intelligent machine to act at the voice of the commander. The latter requirement has always met with opposition in this country and to it has undoubtedly been due a large proportion of our military calamities. Individuality of thought and action is jealously guarded as the heritage of a republican form of government ; and this idea, when carried into the army, constitutes a serious military defect. In the history of the United States Sanitary Commission, published in 1866, StUl^ wrote : "This strange infatuation pervaded all ranks of the people, and, as it seemed a foregone conclusion that discipline such as that which existed in other armies could not be enforced in ours, of course little effort was made to introduce it in the volunteers. The effect was soon apparent. The ignorance of the officers concerning their duties was manifested at the first test. The injury to the health of the troops and, therefore, to their morale and efficiency, mainly due to the ignorance, incapacity, and carelessness of the officers, is now known to have been absolutely disastrous." These remarks might have truthfully been written of our volunteer troops during the Spanish- American War, carried on a full generation later. Tonnochy believes that the mental education of the soldier should include the blunting of the instinct of self-preservation so fan as it can be attained in the living being, and that the individual should be so trained that he is not afraid to be destroyed if only his destruction cost the enemy dear. It is obviously true that the soldier must be taught to accept with resignation the misfortunes of war, and to support with composure the fatigue and privations which are always the price of victories. He should possess a desire for service and glory, should take pride in his uniform and duties, and, over all, entertain a patriotic love for his country. This idea of patriotic devotion and sacrifice serves as a powerful incentive to the soldier ; and moral force, according to Bugeaud, is equal from a military standpoint to the physical force, through the constant stimulus to activity which it engenders. Religious feeling, apart from its moral aspect, is a potent factor in military efficiency, and has been a dominating factor in many military movements. The most difficult peoples to conquer are those fanatics who believe themselves the inspired agents of the Deity, and whose religious teachings lead them to court death in the effort to destroy the unbelieving enemy. Education is of value from the military standpoint purely as it enables the soldier better to perform his duty. HygienicaUy considered, education is important since it broadens the character of the soldier, raises the standard under which he desires to live, and induces a better appreciation of the inevitable and disastrous results which must follow the commission of sanitary faults. Libraries in regiments or military posts are of great value. While containing standard fiction as well as science, they should include historical works, particularly such as express patriotic sentiments and relate the deeds of great commanders. Books pertaining to the care of the health in the military service, and especially those which are de- voted to physical development, wOl prove interesting and desirable reading. THE DEVELOPMEHT OF THE EECEUIT. 73 In conclusion, it has been well written by Woodhull: "Asa conse- quence of efficient military hygiene, which involves moral as well as physical traiaiag, the average recruit at the conclusion of his enlistment is a better man in mind and body, if his company has any discipline worthy of the name. He has learned obedience, responsibility, promptness, order, the value of co-operation and attention to his own duty as moral qualities ; and the importance of cleanliuess, of regular habits and sufficient bodily exercise as physical ones. The slouchy, dirty, careless and perhaps in- subordiuate rough becomes the erect, neat, and disciplined man-at-arms, distinctly charged with the preservation of the peace." CHAPTEE III. THE MAEOH IN CAMPAIGN. In the disposition of the march certain hygienic as well as strategic elements must enter, the former being those of season, weather, physical character of country and the condition of troops. It is evident that if the character of the march be so imprudently designed, in its length or detail, as to fatigue and harass troops, a commander will succeed in break- ing down the strength and spirits of his soldiers ; so that the more he marches and the nearer he approaches the enemy the less fit he will be for the encounter. In a hostile country it is always advisable to keep troops fresh and make only short marches, for fatigue and exhaustion are as inimical to courage and initiative of action -as they are to physical endur- ance. As far as possible military restrictions of an unnecessary natiu'e are to be avoided, since in marching at ease the ordinary jomney is relieved of much of its harassing character and becomes a salutary and stimulant exercise. The men are more cheerful, more contented and capable of higher measure of endurance. The movements of the individual soldier should not be restrained by precise military rules, but should occur more easily in the better maintainance of equUibrium. Preparation. — Prior to active operations in a foreign country it is desirable to thoroughly understand the climatic conditions which wiU be encountered. Such knowledge wiU not only assist in the outlining of the campaign, but will render it possible, should such action be necessary, to alter plans with advantage. If an enemy be drawn into an unhealthful situation and compelled to stand on the defensive or remain under observa- tion imder such conditions, more ultimate benefit may be derived from the depletion of his ranks by disease, and the fi llin g of his hospitals, than by a victory dearly purchased in a doubtful conflict. On the other hand, a knowledge of the medical topography of the theatre of war will perhaps prevent the drawing, by a seasoned enemy, of troops unaccustomed to the coimtry, to insalubrious regions where both disease and the enemy must be combated. In preparing for an active campaign or long march, aU cases of slight iUness or disability should be carefully segregated and left behind, since such soldiers may be considered as practically certain to break down at an early date and become an encumbrance to a marching column. Especially does this apply to the detection and elimination of concealed or partially cured venereal disease, the symptoms of which are notoriously aggravated by such prolonged and arduous exertion or exposure as are inevitable in campaign. Such cases, after recovery, may be later forwarded as reen- forcements, and thus become a source of strength instead of weakness to the command. It is well to remember, in this connection, the spirit of THE MAECH IN CAMPAIGN. 75 military ambition which prevails among such forces as are raised by vol- untary enlistment, as is the case in the armies of the United States and Great Britain. Such soldiers, particularly in time of war, are eager to participate in active service. Inspired by the desire to accompany then- respective commands on campaign, and buoyed up by nervous excitement and fictitious energy, men carried on sick report will often, wilfully or innocently, favorably misrepresent their physical condition to the medical officer in order to obtain consent for their return to full duty. Great care must always be observed that such men, in spite of their praiseworthy de- sires, are not permitted to engage in a march for the accomplishment of which their strength is iaadequate. Under the best of circumstances, ac- cording to Wolseley, in a division of infantry marching one hundred mUes, the probable loss may be estimated at two to three per cent. This percent- age may, of course, be increased by climate, weather, condition of roads and other factors. Troops should never be marched fasting, for such action increases fatigue, lessens resistance and breaks down the barriers against disease. While European armies wiU make a march on merely bread and coffee, our troops require a much more substantial meal. Experience has shown that laborers ia tropical countries, a;ccustomed to work until late in the forenoon with no refreshment except a cup of black coffee, are capable of accomplishing much more if provided with a hearty breakfast before begin- ning their task. The Step. — ^The military marching step, as a means of locomotion, must be considered as far more fatiguing than ordinary walking, since the movements of the soldier are, to a certain degree, unnatural and constrained ^ the ease of the individual being somewhat sacrificed to precision of action. Hence the value of scientific computations as to the work performed by ordinary pedestrians is much diminished in the case of the soldier on service. Until within the past generation it was considered that military methods and customs must necessarily be artificial, and nothing was toO' constrained or even grotesque if it appeared to contribute to the precise manners which were supposed to characterize the military man. Hence it is not surprising to find that until only comparatively recently the left arm was held firmly against the side in marching, much to the interference with the equilibrium of the soldier ; and that, on account of its striking effect on parade, a peculiarly exaggerated high step, in which the thigh was elevated to almost a right angle with the body, was for a long time cultivated in certain European troops and only abandoned through the physical im- possibility of travelling any but the shortest distances' in such a manner. Under present methods of marching the shoulders must be kept straight and the neck and body held erect. The knees are only slightly flexed, and the feet are thrown out well in advance of the body, but the free arm is allowed to swing naturally to better maintain the balance. Such a maimer of progression is not that voluntarily employed by the individual, and hence, on long marches or campaigns or whenever energy is to be con- served, the use of the route step is always advisable. In ordinary walk- ing, the heel touches the ground first ; the greatest weight being borne hy the flat of the foot, and the toe leaving the ground last. Hence the prac- 76 THEORY AND PRACTICE OE MILITARY HYGIENE. tice in the German army, as well as our own, of training the marching soldier to place the foot almost flat upon the ground, increases the shock of impact and is more fatiguing to the individual, especially on a rough Fig. 4— Military or Straight-leg MarcMng. CAlter Bradlord.) terrain. When the leg is at its greatest length, and is lifted from the ground, it is brought forward to a position under, or slightly in front of, the body, by the force of gravity and without muscular exertion ; the action of gravity being also exerted to a certain degree outward. From this point the leg is advanced through the distance required for the next step by the action of the vasti muscles and the straightening of the limb. The foot acts like a lever of the second order, as shown in the accompany- ing diagram (Fig. 5), the fulcrum being at A, the resistance — ^represented by the weight of the body — at E, and the power at P, where the muscles are inserted into the calcaneum. In the ordinary military marching step, the toes should be directed well forward so that the thrust backward in the foot, and especially on the great toe, should be in the direction of its length rather than to a certain ex- tent across it; since the muscular action of the great toe is one of the most potent agents in the propulsion of the body forward. The foot is anatomically so constructed as to sup- port the body weight from the heel, the ball, and the outer portion of the sole ; the inner portion of the plantar surface being concave and not normally coming in contact with the surface over which the individual moves. The more the eversion of the foot, the less the body is supported by the outer surface of the sole and the greater the tendency to break down the plantar arch through the increased weight which must be borne upon its extremi- ties, the heel and ball of the foot. Marked eversion of the foot, such as Fig. 5. THE MARCH IN CAMPAIGN. 77 was formerly carefully inculcated in many European armies, could only result in placing the marching soldier at an anatomical disadvantage which increased his labor, fatigue and discomfort, and directly tended to permanently impair his efficiency by the production of flat feet. On the other hand, iaclination of the foot outward to a slight extent favors the muscular action of the smaller toes and better preserves the equilibrium of the body by affording a broader basis of support over which the body passes in its advance to the front. A moderate iucLLuation outward, of about ten or twelve degrees, probably best answers all requirements. The foot should be raised from the groimd only so far as is necessary to clear obstacles. The marching step recently strongly advocated by de Eaoul, of the French army, was previously unknown to civilized nations, but is com- monly employed in the Orient ; especially among the couriers and footmen of Japan, Ceylon, and India, who are able to cover their seventy-five miles daily for months at a time without great physical effort or serious effects. In this step, known in France as the "pas de flexion," the hips, knees, and ankle joiuts are sHghtly bent, the body is inclined forward and the feet are placed on the ground with little emphasis. According to de Eaoul this method is far less fatiguing than the ordinary marching step, since in the lattfer the body rises and faUs to an excessive degree and so unneces- sarily increases one of the principal ways in which muscular force is lost. It has been photographically demonstrated, also, that the vertical elevation of the body is more than two inches in the ordinary step, and less than one inch in the "pas de flexion." Such a difference at first sight appears to be trivial, but it has been shown by Marey that in marching a mile with the flexion step the energy saved in the lessening of the vertical oscillations of the body was sufficient to elevate the individual through the vertical distance of one hundred and fifty feet — an economy of energy somewhat surprising and well worth consideration. In the Eaoul method the body above the hips is inclined forward to such a degree that the centre of gravity is constantly on the point of being lost, and the only way to prevent falling forward is to keep in motion ; when, as the centre of gravity moves forward, it drags the weight of the body with it without muscular action. To keep pace with this movement with the least effort, the foot should be only slightly raised and should be brought into contact . with the ground glancing rather than flat, thus lessening the shock of im- pact. The pressure on the ground is also said to be lessened. To train in this method, short, quick steps, one htmdred and sixty to the minute, are at first required; their length being gradually increased. The step is noiseless, and the toes are directed toward the front. The distance trav- ersed, as practised in the French army, begins at three thousand yards and increases up to twelve thousand yards. Lessons are preferably given but two or three times weekly, and it is said that a three months' course of training is necessary for proficiency in this step. According to Viry, experiments in France have repeatedly demonstrated that the fully equipped soldier, if trained in this step, can easily attain a rate of eight miles per hour. Of two officers and thirty-two men who were put imder training at Nantes it was recently reported that "after three months' instruction, they marched, carrying their rifles, bayonets, one hundred rounds of ammunition per man, and food for one meal, along 78 THEORY AND PRACTICE OF MILITARY HYGIENE. a hiUy road, a distance of twelve and one-half miles, in an hour and forty-six minutes, which is at the rate of rather over seven miles an hour. Not one man fell out by the way. After a rest of two hours, they re- turned in three hours and five minutes, including two halts of ten min- utes each, which gives an average speed of over four and one-half miles an hour. Two days afterward these same men, in heavy marching order, covered a distance of six and seven-eighths miles across fields, on hiUy ground, in an hour and twenty minutes, which works out at about five and one-half miles an hour. At the end of their march they were at once told off to target practice, when their shooting proved superior to that of the best company of marksmen in the regiment; this was done to determine whether the exer- tions of their rapid march had injured their capabilities as riflemen." It is said that in this method a man's endurance de- pends entirely on the strength of his legs and not on his wind, since the lower extre- mities give out first. The shoes must be very loose, low and comfortable. Long dis- tance pedestrians and soldiers, when tired, unconsciously fall into an imitation of this step, and so bring into action mus- cles which have not previously been used in ordinary loco- motion. The ability to per- form rapid and long marches without the expenditure of an undue amount of energy is a matter which concerns not only the sanitarian, but the tactician. The science of war has been defined as "getting there first with the most men," and this definition was never so applicable as it is to-day. The only objection to this step is that it lacks that rigidity and precision which is supposed to mark the soldier ; but questions of sentiment cannot be per- mitted to outweigh those of practical utility. A thorough trial of flexion marching should be made in our service. The length of the natural step varies with the height of the individual, and, according to Cortial, the proper step of the soldier on the march should not exceed six-sevenths of the height of his limbs. Since the marching step is assumed to be based on the average height and is some- what in excess of the length of the natural step of the smaller men, it is always advisable to let troops take their own step on long marches, for ex- perience amply demonstrates that many men can more easily increase the FlO. 6.— Flexion or Bent-knee Marching. tOTd.) (After Brad- THE MAECH EN CAMPAIGN. 79 number of their steps than they can their length. Should weights be carried the steps must necessarily be shorter, since the length of the step depends on the height to which the body is raised above the ground a condition against which a heavy burden is constantly operating. In the army of the United States the quick or marching step is 30 inches, measured from heel to heel, and the rate is 120 per minute. In double time the step is 36 inches and the cadence 180 per minute. The short step, quick time, measures 15 inches, and the short step, double time, measures 18 inches. The marching step of various foreign armies, reduced to inches, is as follows : In the German army the length is 31.2 inches, and the rate 112-114 per minute. The foot is brought down flat and with considerable emphasis, a method unnecessarily fatiguing and wasteful of energy. The German double quick step has a length of 39.4 inches and a cadence of 165-170 per minute. The step of the English army has a length of 30 inches and a rate of 112 per minute. In the French army the length of the step is 29.5 inches. The cadence at the beginning of the march is 120, and the same during the last half hour of the journey. After the march is well established the rate is accelerated to 125 or even 135 per minute. According to Laveran, the length of the marching step in the Austrian, Belgian, Swiss, Swedish and Italian armies is 29.5 inches. In the Eussian army the cadence is 120 per minute, but the length of the step is only 28 inches. This is extremely short when compared with the marching step adopted by other countries, but appears to be easy and comfortable for troops. The Eussian soldier, according to Tonnochy, throws his weight in both standing and marching more on the heel than the sole of the foot. Prom a large number of elaborate experiments Marey concluded that for a man of average height (which he set at 65| inches) the length of the natural step was 31.7 inches and the cadence 120 per minute. If the same man carried a burden of forty-five pounds the length of the step was reduced several tenths of an inch. In experiments on a man untrained in marching he obtained the following results : Number of Steps per minute. Length ol pace. In inches. Number of steps per minute. Length of pace, In Inches. Number of steps per minute. Length of pace, In Inches. 110 120 28.89 31.72 130 140 32.48 32.79 150 160 38.66 33.26 This shows that there is no value in increasing the cadence beyond 150 per minute; since what is gained in number, at the cost of increase of fatigue, is lost in the diminution in the length of the step. The above results would seem to show clearly the artificial nature of the military step of 30 inches as adopted in our own and some foreign armies, particularly since our soldiers are of greater average height, and vindicates the action of the Germans in selecting a step of 31.2 inches for their march on campaign. Unless guided by the will, the two steps are of unequal length, the 80 THEOEY AND PEACTICE OF MILITAEY HYGIENE. step with 'the right foot beiag somewhat longer than the left. With the eyes closed or ia darkness it is impossible to proceed in a straight line for any distance, a deviation toward the left being noted. In double time the distance traversed per minute is about one hundred and seventy-five yards, which rate, if prolonged, would mean the cover- ing of six miles during the hour. As a matter of fact the double time can scarcely be considered as a marching step, since it should be — and is — ^but rarely employed, and then only for very brief periods. A running step, in spite of all previous training, is quickly exhausting to the soldier, and in- fantry can rarely be justifiably brought into action imder such conditions. Work Done on the March. — ^The march should be considered as labor performed in addition to the daily routine of camp or garrison and not at aU as the only drain upon the energies of the soldier. Still, it is of value to know the amount of work done by the soldier on the march, and this knowledge has been supplied by recent investigation. According Fig. 7.— Positions of the Extremities ol the Soldier During " Double Time." Pliotographs talien at the rate of sixty per second. (After Marey.) to Eubner, the amount of work performed in ordinary walliing, expressed in kilogram-meters, may be calculated according to the formula 0.071 X W N, where the number 0.071 = the height of the step, W = the body weight, and N = the number of steps taken. For the French soldier weighing 64 kgm. (141 lb.), Marey calculated that the expenditure of muscular energy required for each step, the cadence of the march being 120 per minute, was 12 kilogram-meters (1 kilogram-meter being equal to 7.2 foot-pounds). In double time, with a cadence of 180 per minute, the work done with each step was equal to 15.8 kilogram-meters; 0.3 kilogram-meters being due to the movement of the Umbs, 8.0 in the vertical movement of the body and 7.5 in the horizontal translation of the latter. The expenditure of labor in passing over a flat surface varies with the rate of motion, and, according to Marey's experiments, ranged from 25 kilo- gram-meters per second of time to 74 kilogram-meters for the same period. According to Notter and Firth, Coustan and others, the average daily work of the ordinary laborer is from 350 to 400 foot-tons, or about one-sixth or seventh the force theoretically obtainable from the food taken by the in- dividual. Walking on a level surface at the rate of three miles per hour THE MAECH IN CAMPAIGN. 81 is equivalent to raising one-twentieth of the combined weight of the walker and his burden through the distance passed over. For a soldier weighing 160 lb. and carrying a burden of 60 lb., a march of ten miles over flat country amounts to 259.30 foot-tons, or what would be a rather small daily expenditure of energy for the civilian laborer. On the other hand, a inarch of 20 miles with a weight of 60 lb. is alone a very hard day's work for the soldier, without taking into consideration the labor necessarily involved in making and breaking camp and the other laborious duties incident to the field, and, such severe labor could not long be con- tinued without injurious effects. If the ground be not level or the weight badly adjusted the expenditure of energy becomes greater, as is also the case if it be done in a shorter time. Velocity is also an important factor in determining the strain on the heart and lungs. For a soldier weighing 160 lb. to march a distance equaling 300 foot-tons in work done, would mean a journey of 16.3 miles at the rate of three miles per hour. Theo- retically, as ia practice, if the burden be advantageously arranged and the rate of march not too great, the soldier should be able to easily accomplish a per diem of 12 miles with an occasional rest; but a daily march of 20 miles, with fuU equipment, would not be possible for any great length of time. As a matter of fact, however, if very rapid or very long marches are required, the troops are usually sent out in light marching order, with the equipment reduced to the minimum ; or they may later bring the labor within their powers of endurance by discarding portions of their equipment en route. Position on the March. — Since marching in the rear of the column is comparatively much more fatigurag and disagreeable, each minor organi- zation should, in its daily turn, lead within its next higher command — the same rule holding good for regiments, brigades, and divisions ; but newly raised organizations, in marching, should preferably be placed at the head of the column, as they march better in this position, and in case of a skirmish behave better from the knowledge of having the support of seasoned troops. It may be laid down as a general rule that infantry, on the march, should preserve a wide front and as open a formation as may be practicable, in order to avoid the deleterious effects of crowd-poisoning. In marching in dust, close order becomes particularly harassing to infantry, although the reverse is true in regard to cavalry. Infantry should never march with cavalry or artillery, and if a meeting becomes at times unavoidable it is well to move infantry off the road until other troops have passed. Time. — Except in cold weather the early morning is far preferable for marching. The men are fresh, the air is cool, the heat of the sun is not burdensome and the men appear to be less fatigued by their exertion. But for crossing a malarious country the time selected should be the forenoon in the temperate climates and afternoon in the tropics, since the danger of malarial infection is much greater in the early morning before the heat of the sun becomes powerful. Rapidity. — The rate of speed and individual ease with which troops march depends largely upon the size of the command. An ordinary day's march wiU be done in six hours by a regiment, while a division will need eight hours for the same distance. An army corps will require ten or 82 THEOEY AND PRACTICE OF MILITAEY HYGIENE. more hours to complete its day's march — this bekig largely due to the delays and accidents of the march, which are proportionately increased in the case of large bodies of men. On the march, barring halts, a brigade moves its own length in about fifteen miuutes. If no obstacles are to be overcome or especially unfavorable conditions of roads or weather are encountered, the ordinary rate of advance of an infantry column is about two and one-half miles per hour, including the halts necessary to briag the command to its destination in an effective condition and without stragglers. A day's march of fifteen miles is usually accomplished in about six hours. In large comjnands the rate of march of leading regiments should be carefully controlled, erring if anything on the side of slowness. The mounted officer of infantry, setting the pace for his command, should realize the limited capacity of foot troops. If a mixed column be necessary, the rate of march of the infantry must control the speed of the whole. Marches should begin and end slowly. The French have an excellent custom of reducing the rate of march during the last half hour in order to avoid bringing the command into camp in too heated a condition. Length. — ^As to the length of a march any definite rules are impossible, since marching is necessarily largely influenced by the conditions of weather, roads and military necessity. Small groups of individuals, lightly burdened, can march very rapidly ; and military marches appear to be but short to the trained and unencum- bered pedestrian in civil life, he not stopping to consider the fact that work done by one is represented by weight carried plus distance marched, while in the other the same expenditure of energy is applied wholly to the gain- ing of distance. Further, the soldier cannot govern his own actions and must be considered merely as an individual unit of the moving army. His position in the ranks is fixed and must be constantly maintained in order to avoid interference with the space and movements of others. As this applies to the soldier so does it also to the company, regiment or brigade. On the march the soldier is warmly clad for such severe exercise, is unable to stop at the first promptings of fatigue and is compelled to accomplish a certain per diem of locomotion. The weak must keep up with the strong, the man of short stride with the one of long, and the very regularity of the step, when prolonged, tends to make it wearisome and exhausting. It must be remembered also, in computing the length of the march, that the soldier's duties do not end upon his arrival at the camping ground, and that he must prepare his lodgment, procure wood and water, perhaps go on guard, and perform a number of small tasks that are a considerable additional tax upon his energies. As expressed by Smart, the severity of the march must be measured not so much by the number of miles traversed as by the number of hours elapsing between the breaking of camp in one position and its establishment in another. It is a generally admitted principle that for a complete rest after a sustained effort, such as a long march, at least twelve hours in the twenty-four are necessary for both man and horse. Deducting from the remainder an interval of three or four hours for preparation for the march and for duties at the close, there will ordinarily remain for actual marching an interval of five to seven and one- half hours. ' THE MAKCH IN CAMPAIGN. 83 A long hard march, at the outset may defeat the object of the journey hy breaking down a large number of men and rendering them imfit for further marching; and hence, at the beginning of an extended march, unless the necessity be urgent, the distance traversed should be short. This affords an opportunity to the men to become gradually accustomed to the new conditions and the carriage of the equipment. The day's march may subsequently be increased until at the end of a week or ten days the maximum is reached; but in general, when a great distance is to be traversed, the daily marches should always be short rather than long. In the United States a fair day's march for infantry, under usual conditions, is considered to be from fifteen to sixteen miles, or slightly higher than the average in European armies. On long marches or in campaign, the daily march of the English soldier is about twelve nules, occasionally as much as eighteen or twenty. In the march from Cabul to Candahar the expedition, comprising ten thousand men, eight thousand native followers and eleven thousand animals, averaged over sixteen miles daily for twenty-three days. The longest day's march was twenty-one miles. In the French army the average daily march in campaign is twelve and one-half to fifteen miles. G-eneral Lewal considered that a continued march, averaging twelve and one-half miles daily and carrying a equipment weighing forty-five pounds, was an excellent result in campaign. Spanish infantry, said to have no superiors as marchers, regard a march of fifteen miles, under usual conditions, as a fair day's work. In the German army the daily average is fourteen miles, with a halt every fourth day; but, according to Aitken, the Eighteenth (Prussian) Division, in 1870, marched two hundred and sixty miles in nine days in October, and fifty- four miles on December 16th and 17th, heavily equipped and over bad roads. According to Grodekoff, in 1896 a force of about three thousand Eussians made a continuous march of three thousand nules in eastern Siberia, averaging about fourteen miles a day for a large part of the dis- tance. On the entire journey it was found necessary to leave behind only four officers and twenty-nine men, and on arrival the command was in good condition and excellent spirits. It appears to be a well-demonstrated fact that good infantry wOl, in continuous march or long campaign, wear out and out-march cavalry ; but a greater average than fifteen miles daily is rarely achieved, imless by small bodies of men and for short periods. In the case of the soldier, other conditions being equal, weight carried and rate of march must be considered correlative. Beyond the mean established by long experience any attempt at increase in the one must be accompanied by a correspond- ing diminution of the other, or exhaustion quickly supervenes. Meteorological Conditions. — No forethought can guard against marked changes in the weather, and continued marching in long periods of excessive wet, great cold or heat may frequently be more destructive to the efficiency of a command than the results of actual fighting, which at most is of short duration. As a general rule, troops should not be marched in rainy weather, since wet clothing is always to be considered a potent factor in reducing the vital resistance of the soldier and in predis- posing to the occurrence of disease. StiU, while actually exercising but little injury appears to be done to a moving command, and bad effects are 84 THEORY AND PRACTICE OF MILITARY HYGIENE. largely to be attributed to the surface chilling resulting from the frequent failure to change damp clothing on arrival at camp. In marching during wet weather the camping ground should be reached by noon, so that troops may be able to shelter themselves, collect fuel for fires, don the change of clothing carried in the equipment and dry their wet garments before nightfall — ^proper attention doing much to modify the untoward effects of exposure. The length of the march is largely affected by meteorological conditions. As the barometric pressure diminishes so does the oxygenation of the blood, and hence also the vital forces of the organism. If such pressure be greatly reduced, as in the case of considerable elevation, the condition known as " mountain sickness " supervenes ; but as usually observed in soldiers, the effects of rarefaction of the atmosphere are manifested only by hurried and difficult breathing. Temperature exerts a powerful influence on the march. If it be elevated the body is enervated, the muscular system is relaxed and the loss of fluid, through copious perspiration, interferes with the systemic equilibrium. Low temperature, on the con- trary, has a strong tonic effect and stimulates to arduous exertion. Hu- midity, fog and rain render muscular movement and the evaporation of perspiration less free, increase the discomfort of the soldier and therefore by so much impair his efficiency and power. Snow and rain considerably diminish the length and rapidity of the march, especially if the snow-fall amounts to several inches or if the mud produced be deep or tenacious. The moisture absorbed by the clothing and equipment also adds much to the weight to be carried. In dry weather the dust raised by a marching column may become almost insupportable and do much to impair its energies. Head winds greatly impede marching, sometimes to the extent of diminishing the day's march by one-fourth. Terrain. — The soldier is unable to select his own ground for marching, but must maintain his place in the ranks and his rate of speed irrespec- tive of obstacles. Unless the groimd be frozen he marches in the dust or mud created by the regiments which have preceded him ; the discomfort and restriction of respiration caused by one, and the increased fatigue re- sulting from the other, being strong factors in the exhaustion of his energies and the curtailing of his capabilities. If the road be rough the foot is insecurely placed ; if sandy, it sinks ; if muddy or icy, it slips ; if stony, it is liable to hurt or bruise — and all result in the increase of fatigue of the marcher, especially since he is obliged continually to modify his movements according to the nature of the surface and to keep his attention fixed upon the ground in front of him. On the other hand, marches over a smooth, gently roUing country are easier for troops than those made on a level, sandy surface ; since muscles used in locomotion are rested by variety of action as well as by absolute inaction. It is in conformation with this principle that the tired couriers of the Orient walk backward to rest themselves and avoid the loss of time on the way. Whenever possible the movement of troops should occur parallel to the road and the latter be reserved for the use of the wagon trains. This permits the wagons to arrive promptly at the camping grounds, and prevents the occurrence of a long, dispiriting wait, often in rain, heat, or snow. The extra labor in marching over a pathless and possibly broken country is more than neutralized by THE MARCH IN CAMPAIGN. 85 the comfort and satisfaction which the prompt pitching of camp brings to tired soldiers. Equipment. — Soldiers on the march still are, during campaign, loaded down like beasts of burden, in spite of the efforts constantly made in all countries to reduce the weight of the personal equipment. Seasoned troops, wise through experience, will, when ia the field, reduce the weight of their equipment to the minimum. Newly-raised troops, on the con- trary, always overload themselves at the outset ; failing to appreciate the disproportionate amount of fatigue which the carriage of a few extra pounds entails on its bearer in the course of a long march and considering as necessities many articles which they later come to regard as purely superfluous luxuries. Until this latter desirable condition is reached, however, frequent inspections are required to eliminate aU unnecessary and unauthorized articles. Eaw troops, when tired and perhaps overburdened on the march, will often be inclined to discard necessary portions of the equipment which wiU be required for their future comfort and health, and due care must be taken to prevent any such action on their part. Forced Marches. — Such marches are fortunately but rarely required. From their nature they are accomplished under conditions involving scanty food and insuf&cient sleep, which, combined with the unusual fatigue, oper- ate to produce early elimination of the less physically vigorous or untrained individuals of the command. Since the object of the march is not so much to transport men a given distance as it is, while marching, to con- stantly preserve their efficiency and fighting condition, commanding officers should not willingly undertake forced marches, as the risk of break- ing down new troops is too great to be incurred without careful deliberation. On concluding a forced march even the best and most seasoned troops are exhausted, and before being fit for further extended effort require rest and recuperation. Hence a temporary loss of efficiency and a diminution of the effective strength must be calculated in advance as being the price which is to be paid for the position secured. Anything above eighteen or twenty miles is practically a forced march, unless the conditions of the weather, temperature and terrain are extremely favorable. In Mexico, a French column is said to have travelled thirty iniles in five hours at night, rested one hour and then marched nine miles further. According to Thomas, the grenadiers of Oudinot, in 1805, pursued the corps of Werneck for three consecutive days, the daily marches being thirty, forty and fifty miles respectively. Three regiments of British infantry, in July, 1809, marched sixty-two miles in twenty-six consecutive hours, carrying arms, ammunition and packs — in all, a weight of between fifty and sixty pounds. This march implied an expenditure of energy equal to about six hundred foot-tons. One of these same regiments, during the Indian mutiny, marched forty- two miles in twenty hours, and on the following morning marched ten miles and engaged the mutineers. But marches of such character may be said practically to exceed the powers of any large military force under normal conditions. In a forced march, after four hours, the column should be halted for an hour, during which time the men should, if water be at hand and the weather permit, wash the face, hands, neck and feet ; but discrimination 86 THEOEY AND PRACTICE OF MILITARY HYGIENE. as to the duration of the halt must be employed, since the men stiffen up if prolonged rests are permitted. A light lunch should preferably be issued at such a halt. FoUowing a forced march a rest of a day will usually be necessary. Hence such a special effort, besides impairing the efi&ciency of the force, actually gains nothing in distance in a long journey. Night Marches. — Marches at night are rarely necessary. Except under the stress of some imperative military necessity, the loss of sleep and general discomfort occasioned by such marches may be considered to far outweigh the ordinary advantages to be gained thereby. Many soldiers are imable to sleep as well during the day-time as during the darkness of the night, and for these such marches practically destroy all rest. A single night march is not an economy of time, since troops are required to rest the day before as well as the day after the effort. Under an attempt to continue such marching, troops may be expected to break down and an increase in sickness is the invariable result. This was well shown in a recent instance in which, of two French brigades arriving at the same depot, it was stated that the one made prolonged marches partly by night, while the marches of the other were short and slow and always by day. The result, as furnished by the hospital records, was as follows : Marching by Long Stages, Pabtly by Night. Kegiment. Days of sickness. 2nd. 60. 4th. 41. 6th (1st Battalion). 43. Marching by Short Stages, Always by Day. Eegiment. * Days of sickness. 1st. 32. 6th (2nd and 3rd Battalions). 14. 12th. 19. 3rd Chasseurs. 23. Thus those who made long marches, partly by night, lost twice as much time by sickness as those who made short marches always by day, a significant commentary on the hygiene of exercise. Unless the night be very clear or bright, some attempt at the illumina- tion of the route should be attempted by means of lanterns or torches. Night-marching in mountains or rough country is particularly dangerous and fatiguing, and is always difficult. Despite the utmost caution of the soldier he is constantly stumbling, through miscalculation of distance in the deceiving light, and injuring his feet through contact with stones and surface inequalities. Drowsy, out of sorts and tired, he has not the mental stimulus to exertion which the constantly changing scenery of the day march affords. Delays, — To avoid fatiguing delays in starting, the careful regulation of the march is necessary and each organization must be required to arrive at the designated point at the proper time. Having once started on the journey, troops should always be required to continue the march steadily THE MARCH IN CAMPAIGN. 87 and without hesitation, even when minor obstacles, such as mud or pools of water, are encountered ; for delay in advance is transmitted along the column and, the obstacle having been overcome, troops marching in the rear must increase- their pace to regain their lost distance, or leading regi- ments must move slowly or halt to allow the rear to close up. Irregular progi'ess is always particularly vexatious to marching troops. Time lost in waits of indefinite length probably cost more nervous strain and actual fatigue to troops than the same time spent in marching; since the un- certainty of the delay maintains the soldier in a condition of constant un- easiness, prevents the temporary removal of the equipment and destroys much of the benefit which might otherwise result from such a period of rest. Hence whenever occasional halts can be foreseen, they should be announced in the beginning and the whole colunm notified. Even in the case of accidental stops it may frequently be feasible to determine their probable duration, and to make such use of the delay as wiU best conserve the strength and temper of the command. Rests. — In the prevention of exhaustion on the march from too con- tinuous effort, the column should be halted at suitable intervals for periods of rest, and for this purpose frequent short halts during the march give more satisfactory results than by marching with fewer and longer delays en route. Their duration and frequency is thought by PourvoirvUle and others to be determined more by the nature of the country traversed than by the length of the march, and to be directly influenced by the size of the command, small bodies of troops not requiring as frequent rests. Under ordinary circumstances, halts for infantry should occur every fifty minutes and last ten minutes ; but in a mountainous country more frequent stops are necessary, and a breathing time of five minutes should be allowed every twenty-five minutes. For these halts the commanding officer should select situations not too hot, too wet nor too much exposed to the wind. Deep, sandy ravines or places where there is not free circulation of air are to be avoided. A halt at the end of the first two miles enables the men to attend to the calls of nature and to adjust their equipment more satisfactorily. While resting,^ men should divest themselves of their packs and, if the ground be not too muddy, they should sit down. According to Woodhull, the French make use of a method of resting during short halts which saves time, prevents straggling, keeps the soldier off the ground and relieves his fatigue. In this method twenty or thirty men form a circle and each man sits on the knees of the man behind him. If perspiring freely, and exposed to a breeze, soldiers should move about sufficiently to avoid chniing. Overheated or exhausted troops should never lie on the damp ground. If a poncho or blanket is not available to protect against the ground dampness, the soldier should sit on a log or stone, or, failing in this, he should remain standing. It is well, if the march exceed a dozen miles, to halt for half an hour when half way — or about noon — for a light lunch ; and for this purpose a shady, sheltered locality, close to an abund- ance of good water, should be chosen. In addition to those required for resting purposes, halts, in a large command, will now and then be necessary to enable the rear of the column to close up with the main body. If the command has been widely separated, the halt should be continued until 88 THEOEY AND PEACTICE OF MILITAEY HYGIENE. the rear organizations have been properly rested and are in condition to proceed on the journey. Since it is well understood that tired troops cannot march successfully, it will scarcely be necessary to say that laborious field exercise of any kiad should not usually be followed by a march without sufficient delay to allow of recuperation. In pressing the advantage of a victory such action is usually possible under the mental stimulus which is given by success ; but that great risk exists of overtaxing the men under such con- ditions cannot be denied. At the end of a march the feet should always be washed and dry stock- ings put on, and the men should take care not to expose themselves to the danger of chilling. If very warm, and they have no duties requiring phy- sical exercise, extra clothing should be donned. Every eight or ten days, besides Sundays, an all-day halt wiU be required for rest and necessary repairs. Use of Fluids. — In campaign in arid regions, under usual conditions, it is well to estimate the minimum daily allowance of water as not less than one gallon per man. This is merely the amount required for drink- ing and culinary purposes, and makes no provision for the maintenance of personal cleanliness. Much of this water may have to be carried in wagons. Too free drinking of water on the march in temperate climates is inad- visable. Eecruits are prone to drink as often during the day as they approach usable water, and such suffer greatly when restriction is necessitated by the absence of water en route, not marching with the same energy as men who drink in moderation. Soldiers who drink heartily before the start and then habitually refrain from drinking until the noon- day lunch, or until camp be reached, soon learn to feel no discomfort from their failure to drink — and such a custom may be of the greatest service to them in campaign. While arbitrary control over the use of the canteen is unwise and impracticable, it is well to explain to the men the advan- tages of comparative abstinence. During a halt near a cold spring, over- heated soldiers should be prevented from making too free use of the water to their own injury. Canteens should habitually be carried filled. The future cannot always be foreseen, and even if not used on the march the contents may be needed if no water be found at the camp. While the supply should always be replenished at frequent intervals, especially in hot weather, great care must be taken to prevent the use of water from suspicious sources, and men should not be permitted to leave the ranks to fiU. canteens except by spe- cial authority. In foreign countries the civil authorities of towns, through which marching troops are to pass, are obliged to supply an abimdance of fresh water of good quality for this purpose on the request of the com- manding officer of the column. At the halt or in camp a guard placed over the source of supply wiU prevent local pollution by men and animals. Dogs should not be allowed to range with a marching column when approaching water, since, if the weather be warm, they wiU. invariably run ahead to cool themselves in the water. Stock should be watered, and men should wash their persons and clothing, at designated places below the point from which water for cooking and drinking purposes is drawn. THE MARCH IN CAMPAIGN. 89 For use on the march, canteens may advantageously be filled with weak, unsweetened coffee, which appears to quench thirst better than pure water. The employment of tea, from its tendency to attack the metal of the canteen, is undesirable. The use of alcoholic liquors on the march is extremely injurious and provocative of sunstroke. If ever employed they should be used only toward the end of fojced marches, to relieve exhaustion. The patronage of any neighboring saloons by the men, during halts, should be prohibited. Tobacco chewing, and to a less degree smoking, is inadvisable on the march, siace it increases thirst and causes an additional drain on the fluids of the body through the necessarily frequent expectoration. The sensation of thirst may be largely prevented by carrying some small hard object in the mouth, as a twig or pebble, to excite the flow of the salivary glands and so moisten the fauces. The slow sipping of water is said to favor its absorption. Straggling. — Nothing so much harasses troops as straggling on the line of march. Should a soldier find it necessary to fall out between halts for any purpose, special authority from his company commander should be obtained and his prompt return to his place required under pain of punish- ment, his piece being carried by another VLntH his return. During a halt scattering should not be permitted, and the command under all circum- stances should be kept well together and in hand. Straggling is an evil which directly impairs the military efficiency of a command, and, like aU infractions of discipline, may be expected to exert an unfavorable effect upon the general health and morale. Its prevention depends upon careful determination and elimination of the sick, the encouragement and perhaps the assistance of the tired and the application of suitable measures to the lazy and undisciplined. The carefal transportation of the sick will, with good troops, induce extra effort on the part of the latter ; they believing that they will be well cared for should they become exhausted. Convalescents are to be spared as much as possible on the march. Their equipment should, if possible, be carried with the baggage. ' Every precaution should be taken to prevent their becoming wet, since such ■exposure, combined with fatigue, will often return them to hospital. With due precautions they wOl be actually strengthened by not too arduous marching and will shortly be able to return to their full duties in the ranks. Mouth-Breathing. — During the march, breathing through the mouth is to be avoided. This prevents the passage of unwarmed air or particles of dust into the lungs, with resulting possible irritation, and also diminishes the sensation of thirst and tendency toward breathlessness. Mental Occupation. — To occupy the mind of the soldier on the march is an excellent way of preventing fatigue and weariness. Absolute silence is depressing to the men, and should not be required; but frequent talking is undesirable and is to be discouraged. At high altitudes or on ■dusty roads marching soldiers are instinctively silent. Singing en route affords a pleasing mental occupation and does much to lessen the tedium of the march. Nevertheless, in the presence of fog, dust, inclement weather, or during the occurrence of epidemic influenza 90 THEORY AND PEACTICE OF MILITAEY HYGIENE. or bronchial affections, general singiag on the march would seem inadvis- able. The Eussians have recognized this fact to the extent of selecting beforehand certain soldiers to do the singiag for their respective organiza- tions duriag the journey. MUitary music is a diversion and mental stimu- lant and hence is a positive aid on the march. Its rhythm materially assists in imparting and maintaining the proper step and swing, this beiag especially true of fuU bands or the fife and drum. As marching music that of the trumpet is distinctly inferior. Accidents of the March. — In the conduction of the march various conditions may operate to imperil the safety or impair the efficiency of the command. Notably in the first class may be mentioned the disastrous- effects which may result from exposure to extreme heat or cold, which, since they depend more upon temperature and climate than upon the method in which the military march is conducted, receive attention else- where. The second class naturally includes such injuries to the individual which, though theoretically preventable and intrinsically of but slight im- portance, exert a serious and unfavorable influence upon the effective strength and mobility of marching troops. Blisters and Excoriations. — Blisters and excoriations of the feet, in themselves of no importance, often require rest for their recovery. For this reason they possess a considerable interest from a military point of view, especially as they may rapidly render a large number of men imfit for military service and so diminish in large proportion the effective force at the beginning of campaign. Tourraine estimated that after several days' marching about one-fourth of an infantry command would present excoriations of the feet ; while military statistics in general show that from twenty-five to thirty per cent, of troops in campaign, as a result of the first few days' marching, sustain more or less injury to the feet. In the Army of the Potomac whole brigades are said to have been tempo- rarily disabled from this cause ; and it has been estimated that in European armies an average loss of ten per cent, of the effective force, directly due to the hard marching of campaign, must be anticipated among^ unseasoned troops on taking the field. In the early part of the Franco- Prussian war, in the Tenth Army Corps, the constant ineffective from injury to the feet, as a result of marching, ranged from eight to ten per cent. ; and it is said that at one time not less than thirty thousand Ger- man soldiers were, from this cause alone, unfit to perform field service. Such results are partly to be explained by the fact that socks or stockings,, which are of great value in preventing chafing by the hard leather, are not issued to their troops by most European nations, and the soldier must either wrap his feet in small pieces of cloth, as a makeshift, or do without adequate protection. However, under the best circumstances and with all precautions, constant marching must be expected early to render a con- siderable proportion of an infantry command unfit for duty. It thus be- comes evident that care with regard to the feet of the infantry soldier is well recompensed by his increased efficiency. Blisters are naturally produced on those points which support the greatest pressure and friction, these being generally the heel and top of the metatarsal bones. The most painful and serious abrasions usually occur on the heel at the level of the insertion of the tendo AchUlis. THE MARCH IN CAMPAIGN. 91 These cause great suffering to the soldier and usually render his continu- ance on the march impossible. Blisters on the soles of the feet at once disable. In the production of the blister there is an elevation of the epidermis comparable to that which follows a burn of the first degree. Should the epidermal covering be torn off, the skin becomes inflamed and the discomfort of the individual considerably increased. Evacuation of the blister is best done by traversing it with a thread and allowing the oozing of its contents. The raised cuticle may then be greased, pressed into place and, if at night, Kghtly bandaged. Ill-fitting shoes combine with uncleanliness of the feet to disable the marching soldier. Hence it is well to use in daily rotation the two pairs of shoes included in the equipment of the soldier and so prevent a constant pressure upon the same points. On the march the feet are, if practicable, to be kept dry, since continuous moisture softens and loosens the epidermis and favors the formation of blisters. Shoes, when wet, become heavy and rapidly lose their shape ; while damp socks are liable to wrinkle and induce abrasions of the cuticle. The employment of soft, smooth, undamed socks, of good fit and excellent quality, will do much to prevent injury of the feet from marching. Cleanliness of the feet on the march is a prime military necessity. Its- importEince is fuUy understood in European armies, and during campaign each German soldier is required by regulations to wash his feet within two hours after arrival at camp or cantonment. The ablution of the feet, at least once daily, is imperative; and an even more frequent cleaning is desirable during hard field service. Brief immersion in cold water after the daily march has a soothing effect and removes the sensation of burning and irritation ; but prolonged soaking of the feet is inadvisable as softening the cuticle and so tending to promote its injury. If facilities for the complete washing of the feet are not at hand, a thorough wiping with a wet cloth, particularly of the toes, answers an excellent purpose in the removal of grease and dirt. A large proportion of such soldiers as suffer from blisters and excoria- tions — perhaps one half — require medical attention and care, and should be encouraged to apply to the surgeon for relief; but such are not to be readily excused from the performance of fuU military duty. After the washing and drying of sore feet their careful greasing is advisable, particularly of painful localities, before the actual formation of blisters has occurred. For this purpose the fresh tallow of beef or mutton may be used, but the employment of rancid or salted fats is undesirable. Accord- ing to Laveran, an excellent plan is to saturate a pair of cotton stockings with grease. If worn on the march only, and the feet be cleansed and fresh socks donned when camp is reached, a single pair of greased stock- ings will serve admirably for a number of days without washing. A popular method among United States soldiers is to thoroughly soap the foot before beginning the day's journey, thus diminishing friction from the stocking. For hardening the epidermis, foot baths of strong brine or alum solution will be found of advantage as will also the application of alcohol, either fuU strength or diluted one-half with water. For excoriations, the use of astringent ointments, having a basis of lead, zinc or tannin, are often of service. In the German army a two-per-cent. ointment of salicylic 92 THEORY AND PRACTICE OF MILITARY HYGIENE. acid, made up with mutton tallow, is much favored. An excellent pro- cedure, used in the French and German armies, consists in covering the abrasions with waddiag soaked in a ten per cent, solution of chromic acid. In the begianiag of treatment a strength of five per cent, is often sufficient. Excessive sweating of the feet may be relieved by bathing in weak solutions of perchloride of iron or of potassium permanganate. Re- cently weak solutions of formaldehyde have been used for the same pur- pose. The use of finely pulverized alum, dusted into the stockings, is said by Simonton to diminish secretion and harden the epidermis. For similar purposes a foot powder is employed in the German army containing the following ingredients : Salicylic acid, 3 parts; starch, 10 parts; powdered talcum, 87 parts. Of this powder about 5 gm. are used daily by each indi- vidual. Hard corns, if troublesome, may be temporarily removed by scrap- ing with a fragment of broken glass. In the prevention of injury to the feet by marching three factors must receive consideration : the elimination of soldiers with badly formed feet, the issue of a good quality and style of footwear, and the enforcement of cleanliness and such measures of pro- phylaxis as are above noted. Both foot and mounted troops, particularly ia hot weather, are liable to suffer from chafing of the groins and nates as a result of the wearing of ill-fitting, irritating and sweaty imderclothing during the march. A knowledge of the cause of the iajury suggests the remedy, and the same priaoiples should be applied for this condition as have just been suggested with reference to the care of the feet of the soldier. Pied Force. — The swelling of the feet, pain about the tarsal region and functional incapacity to some degree observed among large marching commands was long supposed to be due to a periostitis of traumatic origin. It remaiaed for Boisson and Chapotot to demonstrate in 1899, from Eoentgen-ray photographs taken of a considerable number of cases, that the condition is due to fracture of the diaphysis of a metatarsal bone, usually the second. According to these investigators the fracture is induced by the carriage of heavy weights for long distances over rough roads. The second metatarsal is usually injured on account of its length, slenderness, and proximity to the inner border of the foot. Fixed as it is at its tarsal extremity, under the condition of a lever of the second order, it is in just the position to be fractured. The condition is naturally rarely bilateral. Stout and roomy shoes, with aU possible reduction in the weight of the equipment, will do much to prevent the occurrence of this accident. Heart Strain. — ^A well-defined group of symptoms, for want of a more scientific designation known as " irritable heart of the soldier " or "heart strain," has received considerable attention from military and medi- cal writers — in this country notably from Taylor and Da Costa. These cardiac symptoms usually occur in young and untrained soldiers, especially when weakened by disease or privation, during the occurrence of forced marches and particularly in warm weather. The general symp- toms may be indefinite, but the soldier usually complains of pain in the chest and inability to carry his equipment on the march without losing his breath. The pulse is weak, intermittent and dicrotic, and there is the general appearance of exhaustion. Often there is dizziness, which may occur at night. The condition is brought on by great exertion, particu- THE MARCH IN CAMPAIGN. 93 larly in the absence of proper preliminary training, and especially in such cases as may be affected with latent cardiac weakness, not discoverable upon ordinary physical examination. Since restricted respiratory function must be looked upon as an important exciting cause of heart strain, its occurrence wiU be largely favored by the mechanical compression of the chest waU by tight clothing, belts and the weight and mode of carriage of the equipment. Examination of the heart reveals no valvular lesions, but dilatation of the cardiac chambers, often excessive, may be noted. The right ventricle is the one usually dilated because of its thinner walls, and the greater proportionate strain to which it is subjected. As a result of the examination of a body of soldiers who had marched a distance of fifty nules, Teissier, in 1894, noted that the apex of the heart was dis- placed outward, that its breadth was increased and that the venous circu- lation was impaired. The action of the heart was short and irregular and a well-defined cardiac murmur was present. The arterial pressure was considerably lowered. The action of the heart may be seriously impaired or even paralyzed through the stretching and separation of its muscular fibriUse. Permanent and serious impairment of the cardiac function not rarely results, although the symptoms of heart strain may disappear as long as exertion is not required. A number of cases immediately fatal through cardiac paralysis have been noted, although the condition must be considered rather as chronic than acute. According to Taylor, at the battle of Corinth, during the Civil War, of two companies which had engaged in a lively reconnaissance, one-fourth of the men returned in a state of complete exhaustion, while three soldiers had dropped from the ranks from cardiac syncope and were supposed to be dead. Even under the most favorable conditions, heart strain dis- qualifies the soldier for hard military service ; for the same mode of life which originated the disease wiU operate even more powerfully for its return in the weakened organ. Should a soldier on the march present the symptoms of this affection any tight clothing should be loosened, his equipment removed and he be furnished with wheel transportation. Continuance of exertion in such a case can only result in serious permanent injury to the individual. The prophylaxis of this condition depends upon the prompt discharge from the military service of all soldiers who, at any time, present signs of cardiac weakness. Marches are to be carefully regulated, lest too great exertion induce strain and dilatation of the healthy heart and so create a condition permanently destructive to the efficiency of the soldier. Health. — A marching column is proverbially a healthy column and, barring footsoreness, usually shows a much smaller rate of sickness than when in camp. Daily marching, however, in connection with the concen- trated food usually employed, has a tendency to lead men to neglect their bowels, in the production of constipation. It is of course desirable, in the remedying of this condition, that too strong catharsis be not produced while on the march. As remarked by WoodhuU, for the proper conduction of the march either ample personal experience or careful attention to theoretical detail is required. CHAPTER IV. WATEE. I. aUANTITY, SOURCES, STORAGE AND STTPPLY. Quantity. — The supply of a sufficient amount of wholesome water is :a fundamental sanitary necessity. As a general rule, quantity of supply has a bearing on the health of troops chiefly through its relation toj per- sonal cleanliness. It may, however, under certain conditions, be so scanty as to exert a directly deleterious effect upon the organism of the soldier. The determination of the quantity of water to be provided for troops depends to a considerable extent upon their manner of living and the presence or absence of an efficient system of drainage and sewerage. As far as the soldier is concerned, the results either of a limited supply of water, or of difficulty in removing water which has been used, are very similar. Hence an essential step, in securing the use of an abundance of water, is an adequate provision for its subsequent removal. Whatever the ■quantity of water which is to be allowed, the supply, consideriug the circumstances, should be liberal. There should be proper economy in use and avoidance of waste ; but any error in supply had far better be on the side of excess. For troops in barracks a fair allowance is fifteen gallons per capita for all purposes except baths and water closets ; of this amount about one and one-half gallons being required for driuking and cooking. A daily supply in garrison of five gallons is probably the minimum compat- ible with health, and with this quantity proper cleanliness of the person and surroundings cannot be maintained. "Water closets require four to six gallons daily for efficient flushing, according to the pattern used ; and in this particular instance a false economy in the use of water is most undesir- able. A certain amount of water, when the post is sewered, about five gal- lons per capita, will advantageously be allowed to run to waste in each twenty-four hours in order to maintain due cleanliness of the sewer pipes. Where shower baths are used, an allowance of three or four gallons a head is sufficient for a daily bath. If the tub bath system is employed, the amount of water required for each bath is much greater — forty to fifty gallons — ^but such baths are less convenient and are probably taken less frequently. Taking all factors into consideration, together with the matter of un- avoidable wastage, it is probable that a daily allowance of not less than thirty-five gallons will be to the best interests of the soldier. In the British army each adult is entitled by regulations to receive twenty gallons, and each child ten gallons, per diem. According to Viry, the minimum allowance in the French service is seven and one -half gallons to the foot soldier, nine gallons to the cavalryman, and twenty- WATER. 95 five gallons to each kitchen. In Germany, according to the same authority, the daUy allowance is twelve and one-half gallons to each soldier. These amounts are obviously quite insufficient for the main- tenance of the standard of cleanliness, as regards person and surroundings, obtaining in the army of the United States. In hot climates a much greater quantity is required for washing and bathing; and probably a supply of fifty gallons per diem, under such circumstances,- should be re- garded as the minimum. At certain western stations ta the arid belt, where the water supply from rainfall is never very gi'eat and is somewhat uncertain, the supply of water available may be, at certain periods, insufficient to meet demands for all purposes. Nearly all posts of this character, however, have been abandoned dftring the last few years. For hospitals a much larger quantity of water must be provided than is required for barracks. Where possible the supply should be unlimited. There is necessarily much bathing and washing in such institutions, and with a considerable proportion of typhoid cases the average daily consumption, per capita, may readily reach two hundred and fifty gallons. The minimum quantity of water ordinarily to be supplied during active campaign amounts to about two gallons daily, divided as follows : For drinking and cooking purposes, four and one-half quarts; for the maintenance of cleanliness, two and one-half quarts ; unavoidable wastage, one quart During great emergency the matter of bodily cleanliness may be disregarded, and the amount of water for drinking and cooking purposes reduced to about three or four quarts — but such reduction must obviously be only temporary. During campaign in hot weather or in the tropics it is probable that a daily allowance of three gallons should be considered as the minimum compatible with a reasonable degree of comfort. During a march the water supply is limited, consisting for each man of what can be carried in the canteen. No dependence can often be placed on the probability of replenishing the supply while en route, and hence the guides for use should be the water level in the canteen and the length of the day or journey, rather than the desires of the individual. Experience shows the capacity of the canteen, one quart, to be often insufficient during long marches in hot weather; but it is especially under these conditions that the overloading of the foot soldier by an additional burden is highly inadvisable. For mounted troops no such objection obtains, and hence for long marches in a hot and waterless coimtry the carriage of an extra canteen by the cavahyman will usually be of advantage. In certain regions, water is so scarce that judicious management is required to for- ward troops over the route. Some camping stations may have enough for only one or two companies or regiments, and the command, if larger, must pass in detachments. Where the distance between the nearest supplies of water is too great to be marched without rest, a dry camp must be made at some suitable intervening point, as much water as pos- sible being transported with the command. For stationary camps the minimum quantity of water to be supplied each soldier, for all purposes, should be placed at about five gallons. If the quantity be more than ten gallons per capita its proper disposal, in the absence of sewers, may become a serious problem. 96 THEORY AND PRACTICE OF MILITARY HYGIENE. Horses require, as a daily minimum, six to eight gallons of water for drinking purposes, according to season and work, with an additional allowance of about three gallons for the maintenance of cleanliness. If a horse be given free access to water, he will take eight to ten gallons daily, and sometimes more, drinking from one and one-Tialf to two gallons at a time. Mules and cattle drink slightly less than horses. In the expedi- tion against Santiago, the official allowance of water for horses and mules was six gallons per capita, this appearing to be sufficient. In the Brit- ish service the maximum allowance for each public animal is twenty gallons. Where watering the streets of the camp or post is necessary, the dust may be laid by the use of two hundred and twenty-five gallons to each six hundred square yards of surface. In providing the amount of water required for this purpose, the probable number of dusty days, as well as the superficial space to be watered, should be taken into consideration. Permanency. — ^In the establishment of a military post or standing camp, the importance of determining the permanence of the water supply is obvious. To this end any available evidence should be obtaiued; particularly with reference to the amount and period of rain, without which it is impossible to arrive at any safe conclusion. The coimtry which forms the gathering-ground for the springs or rivers should be considered. If there be an extensive background of hills, the springs toward the foot of the hills will probably be permanent. In a flat country the permanency is doubtful unless there be evidence from the temperature of the spriag that the water comes from some depth. In limestone regions, springs are often fed from subterranean reservoirs, caused by the gradual solution of the rocks by the water charged with carbonic acid, and such springs are very permanent. In the chalk districts there are few springs or streams, on account of the porosity of the soil, unless at points where the level is considerably below that of the country generally. The same may be said of the sandstone formations, both old and new; but deep wells in sandstone often yield largely, as the permeable rocks form a vast reservoir. In the granitic and trap districts small streams are liable to great variations, unless fed from lakes; springs are more permanent when they exist. Much also depends upon the quantity and character of the vegetation of the watershed. Wliere the country is well wooded, the trees, undergrowth and especially the dead vegetable matter covering the ground do much to retain moisture and render its percolation to lower levels a gradual process. The roots of vegetation gi-eatly promote absorp- tion of the rainfall. Further, in northern climates, heavy vegetation greatly delays the melting of snow in the spring, and thus assists in creat- ing a supply of water for the dryer summer months. If the watershed be cleared of timber and brushwood the volume of existing watercourses is materially altered, a steady supply at aU seasons being replaced by alter- nating periods of freshet and drought. This is a matter of particular im- portance in those regions, as m the arid belt of the west, where the annual precipitation is small, and is limited to certain seasons. Several military posts established on what had previously been perennial streams of ample volume have had their existence threatened as a result of the greatly de- creased water supply which followed the mistaken policy of permitting WATEK. 97 indiscriminate felling of timber and unchecked forest fires. In one instance the removal of a large number of beaver dams allowed the rapid escape of waters during the spring floods, none being retaiued to trickle down into the reservoir of the post during the dry season. In determining the sufficiency of a water supply for a proposed post, the decision should be obviously based upon estimates made during the period of least flow, and preferably for the dryest year. Rain Water. — Eaia water approaches nearer to purity than any other kind of natural water, receiving only such contamination as may be derived from the atmosphere. This water is highly afe'rated, containing a greater proportion of oxygen as regards nitrogen than does atmospheric air, through the readiness with which the former gas passes into aqueous solution. Through its purity and ae'ration it is both healthful and palat- able ; and ^hen the supply from the surface or ground water is poor the use of rain water is desirable. Through the absence of earthy salts, rain water is very soft and admirably suited for purposes of cleanliness .and cooking. "Where proper arrangements for its storage in tanks or cisterns can be made, the use of such water is calculated to limit the diseases ordinarily transmitted by water. This is especially the case in time of epidemics, when infectious material so frequently finds its way into the general source of water supply for the community. The uncertainty of the rainfall from year to year, the length of the dry season in many localities and the large si^e of the cisterns which are then required are the disadvantages of using water from this source. The use of cisterns as a source of water supply for troops is still continued at Fort Stevens, Fort St. Philip, Jackson Barracks, and other stations. At many small artillery posts no other method of supply is available, and it has happened, in periods of drought, that water has had to be brought in by boat and pumped into the cisterns. At certain western stations, notably old Fort Sisseton, established for military reasons away from an abundant water supply, cisterns were employed for the purpose of supplementing the scanty and uncertain local supply. In determining the amount of water available from the rainfall, the precipitation during the period to be considered and the area of the re- ceiving surface must be known. The former can be determined only by a rain gauge ; the latter may be measured. To calculate the receiving sur- face of a roof, the slope should not be taken into account, but merely the flat surface actually covered by the roof. The external dimensions of the building, when multiplied together, give a superficies slightly less than the area of the roof, which also includes a certain space due to the projection of the eaves. For military purposes it is sufficient to multiply the area of the receiving surface by half the rainfall in inches, the result being in gallons. The error by this calculation is only about four per cent. In estimating the size of the cistern required, besides the amount of water to be used daily, the least, the greatest and the average annual rain- fall should be known ; together with the period when it falls, and the duration of the rainless season, when no replenishment of the supply, from time to time, may be expected. The average of twenty years, less one- third, gives very accurately the amount of rain in the driest year ; and the same average, plus one-third, gives very nearly the amount in the wettest 7 98 THEORY AND PEACTICE OF MILITARY HYGIENE, year. The average of the three driest years in twenty is a safe basis for computation. It may be assumed that about six-tenths of the rainfall is ordinariLy available for storage. For the construction of large cisterns the best material is ' brick or stone, thoroughly cemented inside. Common mortar should not be allowed to come in contact with the contained water, since lime is readily taken up and the water becomes hard. In the construction of small cisterns, slate may be advantageously employed, but is somewhat liable to leakage. For tanks above ground, galvanized iron is much used. Where common boiler iron is employed the metal corrodes and colors the water; in such instances the application of an interior coating of cement or asphaltum paint is advisable. Wooden tanks should not be used, especially in hot climates. Where there is great fluctuation in the water level of a wooden cistern, organic development is liable to occur and the tank itself readily falls out of repair. IJeceptacles for the storage of rain water should always be well covered to prevent pollution of their contents, and be thoroughly ventilated if of Fig. 8.— Separating Tank for Ealn Water. any great size. Light should be excluded to prevent the growth of vegetation. Care should always be taken that there is no leakage into them, a contingency impossible if the cisterns be above ground. Where the latter plan is adopted, a large iron tank, on a suitable platform, is per- haps the best reservoir; bearing in mind the fact that in addition to the weight of the tank each gallon of water stored at a temperature of 60° F. will weigh about ten pounds. It is important that the overflow pipe be not directly connected with a sewer — thus allowing the absorption of sewer gases — ^but be made to discharge above ground over a trapped grating. The amount of dust collected on a roof during periods of prolonged drought is by no means inconsiderable ; and to this may be added organic matter in the form of leaves, mossy growths and the excrement of birds. Such materials impart a peculiarly unpleasant taste to cistern water, as well as being a possible agent in the production of disease, and hence the separation and rejection of the first portion of the rainfall is desirable. This is readily accomplished by several forms of automatic apparatus, the most simple of which is a receiving tank operating a float, the latter mov- ing a plunger in a divided pipe so as to divert the stream of water from one pipe through the other after the tank is filled. According to Viry, it WATEK. 99 has been determined that a rainfall of one liter on each two square meters of collecting space is ordinarily sufficient for securing cleanliness, and hence the dimensions of the separating tank may be calculated accordiagly. In the absence of automatic apparatus of this character, the rejection of the roof washings may be less conveniently accomplished by inserting a joint in the conductor, which, when in place, leads the water into a cistern, but when turned runs it to waste. It is always advisable to filter rain-water before storage. This is preferably accomplished according to the plan shown ia the 'accompany- ing illustration. Where this cannot be done, the cistern may be divided into two compartments by a tight partition having several openings near the bottom. In one compartment is placed the filteriag material, usually composed of three or four feet of clean, coarse sand. The roof leader empties into this side, while the filtered water is drawn from the other compartment. Where the cistern is so large that it cannot well be covered, a second smaller tank, capable of holding a few days' supply, might be Fig. 9.— Method of Filtering Rain Water. (After Parlies.) provided and fitted with a filter through which water from the larger reservoir could be led as required. Cisterns should be periodically inspected and cleaned. This is a matter of great importance ; since there are recorded many instances of the grossest kind of pollution of cistern water, arising from ignorant neglect of what would seem very evident and simple precautions. Surface Waters. — The water of large lakes is usually excellent and free from any great impurity. The mineral matter present, in both nature and amount, largely depends upon the character of the soil over which the water rests ; but ordinarily, with the exception of lime salts, the quantity of dissolved mineral matter is small. The organic material present is chiefly of vegetable and not animal origin. In small surface ponds the water is frequently unwholesome from the high degree of vegetable im- pregnation and is largely exposed to animal contamination, while concen- tration by evaporation may render such water more deleterious. Water from such sources should ordinarily be regarded as imsafe. Marsh water should be unhesitatingly rejected as a source of supply for troops, being rich in organic matter and hence in the lower forms of 100 THEORY AND PEACTICE OF MILITARY HYGIENE. animal life. It undoubtedly has a strong influence on the prevalence of dysentery, and is presumably a medium by which the causative agent of malaria finds its way into the organism. Fed from a variety of sources and directly influenced by season and meteorological conditions, river water is usually complex in its constitu- tion. Sometimes river water is almost as pure as raia water ; or it may, on the other hand, contain a high proportion of miaeral matter, or be foul from pollution by sewage or other impurities. An excellent index of the potability of river water is ordinarily given by the character of the country through which it flows, and the density of the population along its banks. In general, river water is both good and palatable ; but streams receiving the sewage of towns or undergoing pollution from the encampment of large bodies of troops along their banks are dangerous sources of supply for many miles below the point of contamination. It is true that surface, and espe- cially running, water undergoes self -purification ; but the factors bringing about this end are dependent upon such variable conditions that it is scarcely possible to determine both rapidly and accurately the point at which such water again becomes suitable for human consumption. As far as the military sanitarian is concerned, it is probably safe to consider aU running water receiving a proportionately large amount of organic contamination within the distance of one day's march for foot troops, estimated on the meander line of the stream, as at least suspicious. This process of self -purification of surface waters varies greatly in rapidity, according, as stated above, to the presence or absence of varying factors. Solid sewage is soon deposited on the bed of the stream or be- comes food for fish and the lower forms of organic life. Dissolved or particulate organic material, in a rapid current, breaks up quickly under the influence of the large amount of oxygen held in solution in such highly aerated waters, and the same factor is inimical to the development and existence of pathogenic micro-organisms. The latter also are probably destroyed by the hard particles of sand or grit held in suspension in a turbid water and with which they constantly come in violent contact, while the sedimentation of such earthy particles in stiU waters results also in the mechanical entanglement and deposition of a considerable proportion of the germ life. Kruger, in investigating the influence of precipitating mud in hastening the fall of suspended bacteria, and using one-half gramme of fine sterilized potter's clay in each liter of water, obtained the following counts of bacteria in each cubic centimeter, the water' being maintained at 55° r.: Watek with Clat. CONTROL Water Containins No CLAY. Top. Middle. Bottom. Top. Middle. Bottom. After standing two hours After standing twenty hours . . After standing fifty hours 575 531 6,938 887 155 6,190 33,495 43,595 66,350 5,340 5,960 7,330 6,110 6,710 5,987 5,480 6,210 6,924 In addition, the solar rays are powerful factors in the destruction of bacteria, the blue and violet rays being particularly germicidal. This in- fluence of the solar rays has been ingeniously shown by Buchner, who WATER. 101 exposed a Petri dish, thickly sowed with the typhoid bacillus, to the sun- light ; certain parts of the dish being shaded by letters of the alphabet cut out of black paper. After six hours' exposure the dish was removed and placed in an incubator, subsequent examination showing no development of bacteria on the parts exposed to the sunlight, while a strikingly luxuriant and well-defined growth occurred on the parts shaded by the black letters. Buchner also foimd that the germicidal effect of sunlight was pronounced even at considerable depths of water, plates of nutrient gelatia inoculated with the typhoid bacillus being steriliaed by exposure during four and one- half hours at a depth of five feet three inches in lake water. Similar plates, however, exposed at a distance of ten feet below the surface, ex- hibited but little dimiuution of vitality. It is obvious that the degree of turbidity in a water markedly influences the action of sunlight on the contained micro-organisms. Where a considerable body of troops is to be encamped or stationed on a small watercourse, it is often important that the sufficiency of supply Fig. 10. —Side View of Weir. furnished by the stream should be determined. Should it be required to ascertain the yield with great exactness, the plan most generally adopted by engineers consists in the use of a carefully leveled weir of thin board or metal in which a rectangular notch has been cut, having a width of one foot. The water flows over this weir in a thin sheet, the difference in height between the apex of the notch and the level of the water flowing through the notch being measured. If the weir is more or less than a foot, the quantity in the table opposite the given depth should be multi- plied by the length of the weir in feet, or decimals of a foot. If the wen- measure one foot, and the depth of water falling over be two inches, the delivery is read at once, viz., 13.63 cubic feet, or 84.9 gallons, per minute. The following table of reference is given by Notter and Firth : Depth falling over, incbes. Discharge per minute, cubic feet. Depth falUng over, inches Discharge per minute, cubic feet. Depth falling over, inches. Discharge per minute, cubic feet. i 1 n 1.70 4.82 8.84 2 2i 3 13,63 19.70 26.62 3* 4 33.22 40,71 For the purposes of the military sanitarian, however, sufficient accuracy may be attained by selecting a portion of the stream where the channel is 102 THEORY AND PEACTICE OF MILITARY HYGIENE. fairly uniform, and presents no eddies for a distance of fifteen to twenty- yards. The sectional area is obtained by measuring the breadth and depth in several places. A chip, cork or other light object is then floated over a certain distance of the portion of channel chosen, the surface velocity in feet per second being thus obtained. The surface velocity, however, is greater than the bottom or mean velocity, and hence four-fifths of the sur- face velocity — ^being nearly the proportion of mean to surface velocity — multiplied by the sectional area, will give the yield of the stream per second. It may sometimes be worth while, if labor be available, to remove some of the irregularities in the channel before calculating the yield of a watercourse. For greater nicety the stream may be dammed, and the water passed through an artificial channel, as a wooden trough, of known dimensions. Where a stream which serves as a source of supply is small, it is frequently desirable to accumulate during the night and hours of non-use the water which would otherwise run to waste, and thus provide a sufficiency for the great demands made upon it at certain periods duriug Fig. U.— FronfView of Weir. the day. The storage of surface water occurs naturally in depressions of the ground surface, and its collection by artificial means consists almost entirely iu imitatiiig these natural processes. Special arrangements are necessarily required in each case. In hilly countries a reservoir is usually formed by carrying a dam across a valley receiving the tribu- tary waters of adjacent hills ; or on a flatter surface, trenches may be arranged, leading finally to an excavated tank. In form, a reservoir should be deep rather than extended, so as to diminish evaporation and secure coolness. Previous to coUecting the water the bottom of a proposed reservoir should be policed, and, as far as possible, be cleared of aU vege- table material. Decomposition of recently killed vegetation takes place under water quite rapidly at first, but the process is soon converted into one of exceeding slowness, particularly when the covering water is deep. Alternate flooding and exposure to sun and air is quickly destructive of vegetable matter ; and as a result, a reservoir with very gently sloping sides furnishes conditions favorable to a contaminated water supply, particularly if the water be liable at times to considerable reduction in depth. Even though the level of the contents be maintained at high-water mark, sloping sides permit thin layers of water to be overheated by the summer sun ; thus encouraging a growth of aquatic plants which subsequently decay to the damage of the water. The reservoir and its vicinity should be kept scrupulously clean, and no possible source of contamination should be per- WATER. 103 mitted to exist. For temporary encampments, the quantity of water to be stored depends usually only on the quantity used, but for permanent garrisons the ease of replenishing must also be taken iato consideration. There are also losses incidental to storage which must not be overlooked, these being chiefly due to the processes of percolation and evaporation. The formula for storage given by Notter and Firth is as follows : p— ' ■\/F where F represents the mean annual rainfall in inches and D the number of days' supply to be stored. It should not be forgotten that surface water is extremely liable to pollution, and hence a careful inspection of the surroundings of a proposed source of supply is of the greatest importance, the question of the probable healthfulness of such water being often necessarily decided, in the military service, by such inspection. Surface water is particularly liable to con- tamination by sewage, manufacturing waste or organic refuse ; by manure washed down from cultivated lands of the watershed ; by animals pastured on the gathering ground or having direct access to such water supply ; by FIG. 12.— Method ol Forming Eeservoir for Camps. dead animals in such situations ; by refuse from encampments and by persons bathing or washing clothing. Of these, contamination by sewage and organic refuse is the most important in its relation to health, and with the settling up of sparsely settled districts such later contamination of the water supply has forced the abandonment of garrisoned posts, recently that of Fort Custer. Where surface waters are used as a source of supply by a marching command, great care is necessary to prevent a supply, originally pure, from rapidly becoming contaminated and imfit for use as a result of lax sanitary administration; the danger being less in the case of ground waters. To this end the of&cer entrusted with the duty of forming an en- campment for troops in the field wOl promptly place a guard over the water supply, taking the sentries from the first troops that arrive on the ground. When the camp is completely formed, the regular guard should take charge of the supply. Under such circumstances every effort should be made against waste, against pollution, and against the turbidity which results from trampling the margin of a surface supply into mud. If the camp is of any permanency and the water is derived from a small stream, the approach should be paved and so located that the water may be dipped from the main current and not from a foul eddy. Where the siapply is 104 THEORY AND PRACTICE OF MILITARY HYGIENE. taken from such a source, the water used for drinking should be drawn from a part well above the camp ; for watering animals a place should be selected below this, and the lowest part devoted to bathing and the wash- ing of clothing and utensils. Where an encampment is located on a large body of water, as a lake, the points at which water may be drawn, animals watered and washing carried on should be widely separated and specially designated. Where a camp is of any permanency, water will be best given to animals, if the supply is limited, by receiving it first in troughs, as by so doing less disturbance of the stream results. As a general rule, the less the water supply the greater the care necessary to maintain its purity. An essay for the use of volunteers, published in 1861, advised placing latrines over running water when possible. Fortunately this was corrected in the next edition ; but the same mistake was made by raw troops during the war with Spain, and the incident is cited to show that the importance of guarding the water supply is sometimes strangely overlooked. Noth- ing is better established than that no refuse, and especially no fecal matter, should be discharged so as to follow a stream, either directly or indirectly, unless it be one of the great rivers, and then only when it is certain that the water is to be used by no one within a reasonable distance. It is suicidal to pollute small streams which may possibly supply our own forces sooner or later, and it is nothing less than criminal to spread disease in tliat way among a civil population, or even among an enemy. In hard soil especially, a water supply at a lower level — even if it be at some distance — is liable to be sooner or later polluted in spite of ordinary care and give rise to enteric fever and other water-borne infections. Ice used in the military service within the United States may be con- sidered as wholly derived from the congelation of surface waters due to natural processes. In freezing, water becomes much purer, losing a large portion of its saline contents, even calcium carbonate and sulphate being largely reduced in quantity. Air at the same time is expelled. Water produced by the melting of ice is thus usually pure but heavy and non- aerated. Snow water contains less ammonia, carbon dioxide and dissolved oxygen than raiu water. Clear ice is much purer, as regards both mineral and organic matter, than snow ice; the former containing only six per cent, where the latter contains twelve per cent, of the organic matter in the water from which they were derived. As to bacterial life, Notter and Firth state that snow ice has been found to contain as much as eighty-one per cent, of the amount present in the water, while clear ice contains only two per cent. Prudden found the number of bacteria, per cubic centimeter, in water derived from several samples of melted ice cut from the same cake, to be as follows : Transparent ice, 2,322 ; bubbly-streak ice, 26,049 ; snow ice, 55,062. It is thus obviously much safer to use clear ice for cooling driakiag- water, and for placing in contact with food. If distilled water is employed in its manufacture, artificial ice made by the can system is extremely pure. Where ordinary water is used, the outer portion of the cake is pro- portionately free from impurity, but the centre of the cake, through concentration, is highly impure. Prolonged freezing has no marked effect upon the vitality of the typhoid bacillus, though alternate freezing and WATER. 105 thawing have. It should, therefore, be an unvarying rule that ice should never be cut from bodies of water which are not iu every way suited for driuking purposes, and due care should be taken to prevent its contamina- tion during the operation of harvesting and storage. Ice may be fairly well preserved ia cool climates, for use in warmer weather, by heaping it up in layers, protected by sawdust, under an ordinary shed; or by storing it in the same manner in properly drained excavations in the ground. For permanent posts, ice-houses should be constructed on the general plan detailed in the section on tropical hygiene. Ground Water. — Spring water is both pure and impure in different cases ; and the mere fact of water being derived from a spring is not, as sometimes imagined, necessarily an evidence of goodness. As a general rule, however, water derived from such a source may be regarded as of excellent quality and well adapted for use by troops. No small number of stations in this country are supplied with water from springs, among them being such important posts as Angel Island, and Forts Huachuca, SneUing, and Eobinson. For standing camps, springs have the greater merit of being a source of supply the contamination of which can be readily prevented. Pasteur and Joubert long since found that spring water, on . emerging from the soil, usually contained but few micro- organisms, while after comparatively brief contact with the surface it con- tained vast numbers. Spring water is clear and bright, in consequence of the great degree of filtration which it naturally undergoes in percolating through the strata which it may have traversed between the gathering gi'ound and the point from which it issues again from the earth. For the same reason it is generally cool, unless coming from a depth much above two hundred feet; and by the reason of the gas it contains, is sparkling and brisk to the taste. The temperature of spring water varies, and is generally regulated by the depth. The yield of a spring is determined most readily by receiving the water' into a vessel of known capacity and timing the rate of filling. The spring should have previously been opened up and the receptacle employed should be of large size. The capacity of the vessel used as a standard may be found by filling it by means of a known measure or by determining its several dimensions, capacity in cubic feet being reduced to gallons by multiplying by 6.23. If a tub or cask only be procurable, its capacity may be determined by measuring the diameter midway between the bung and the head, designating this measurement M. The bung diameter is called B, the head diameter H and the length of the barrel L ; then (H'' -f- B^ + ^ M') X L X 0.0004721 will give the contents in gallons. Should a spring be steady but small in volume an increased supply may frequently be ob- tained by digging out the spring head. A box or barrel, from which the bottom has been removed, should always be sunk in a spring head, to prevent fouhng of the water through its disturbance during removal. Where used for any length of time a spring should be enclosed, its level raised and the ground made to slope away from rather than toward it. If this is impracticable, the vicinity should be so ditched that aR surface drainage from higher ground is intercepted and conducted to a point below the level of the spring. The latter should be frequently cleansed and all accumulations of leaves or debris removed. 106 THEOEY AND-PEACTICE OF MILITAEY HYGIENE. Artesian wells are practically springs of artificial origin. They are generally of great depth and tap a sheet of water held under high pressure between two impermeable strata, both of which crop up elsewhere at a higher level. In the military service, artesian wells will only rarely serve as a source of water supply. During the war with Spain, however, wells of this character furnished the water' consumed by troops at several of the large camps in Florida ; and they are also in use at the garrisoned posts of Forts Logan, MoPherson, St. Francis Barracks and Vancouver Barracks. Water from such a source is usually of excellent quality and contains only a very minute quantity of organic matter. In some cases, however, it is so charged with saline matter as to be undrinkable. The waters of the artesian wells in Florida, above mentioned, were highly charged with sulphur dioxide ; this gas, however, being rapidly dissipated on ex- posure to the air. As a general rule, artesian water is not well aerated and is by no means as palatable as spring water. Laveran states that water furnished by artesian wells is usually quite sterile. Excavated wells, while properly to be rarely employed as a source of water supply ia garrison, may frequently be called upon to supplement a Pie. 13.— Diagram Showing how an Impermeable Stratum, d. May Permit Water in Wells, a, 6, and c, to be deriyed from different levels. (Alter Mason.) deficient water supply in the field. Such weUs are usually classified as deep or shallow, according as the depth is greater or less than fifty feet. Deep weUs, rarely found in the military service, are usually good sources of supply; the great efficiency of the filtration which most of these well waters have undergone being attested by their freedom from suspended material, either mineral or organic. Water from such wells is usually pure, and, unless extremely hard, excellent for drinking purposes. Shallow wells, on the contrary, are readily exposed to contamination by surface drainage or soakage, and the water from such wells is always to be re- garded with suspicion. The amount of organic matter in shallow wells is usually large, and is too often of animal origin. In locating such weUs in the field the ground for a radius of one hundred yards should not be camped upon and a site should be selected entnely free from the danger of overflow by storm water. If possible, the mouth of the well should be sheltered, and a sufficient coping to prevent possible accident and limit contamination is always necessary — the level of the surrounding ground being made to slope from and not toward the mouth to prevent the en- trance of surface water. Precaution should be taken for the conduction to a short distance of such water as may be spilled after being drawn, so that it is not immediately returned to the well saturated with the organic WATER. 107 material dissolved during percolation through, the necessarily polluted soil around the well site. "When used in garrison, wells should be stoned and rendered impervious to surface soakage by an interior coat- ing of cement; but ia the field this precaution is obviously impossible. For very shallow, temporary weUs, an excellent plan to prevent cav- ing of the walls and facilitate the drawing of water consists iu a frame- work of plank, set in the excavation, the earth previously removed being packed around this frame. For weUs not greater than twenty-five feet in depth, in soft soU, the removal of earth during the process of ex- cavation may be accompanied by the forcing down or, building of a protecting frame, these frames being necessarily made progressively smaller as the depth of the well is increased. For such weUs a light pump provided with a rubber pipe of sufficient length to reach the water level can be used with ad- vantage. A pump is always much superior to the rope and bucket system, through the lessened danger of pollution by the former means. A well drains an extent of ground around it nearly in the shape of an inverted cone. The area must, of course, depend upon the soil; but it has been demonstrated that the radius of the surface area drained is ordinarily at least equal to four times the depth, and that it often exceeds this. The curve of the subterranean water-level rises suddenly near the well and becomes gradually flatter as it extends under the ground surface, the distance to which it reaches depending on the lowering of the level of the water in the well. Thus a shallow well heavily pumped may drain a wider area than a deeper well under moderate pumping — ^this fact being of great significance in connection with wells in a densely populated encamp- ment, where soil pollution is both extensive and rapid and where the with- drawal of water is constant and great. The distance to which the influence of pumping is felt on the ground water is very variable, ranging from fifteen to one hundred and sixty times the depression of the water in the well. A well which yields a moderate quantity of good water may thus, if the demand on it be increased, draw water from the surrounding parts to meet the demand, and thus tap sources of impurity which a moderate demand left untouched. A sudden rise in the ground water may also lead to communication between a cesspit and a well, by the water tapping the former in its flow. The trend of the sub-soil water at any given point being always in the direction of the nearest natural outlet, when such exists — as a spring, stream, or sheet of water — it is evident that the purer water will be fomid before it passes such possible point of pollution. For this reason it is possible, in the case of two wells situated only a short distance from each other, that one may yield a pure water Fig. 14.— Temporary Well for Encampments. 108 THEOKY AND PRACTICE OF MILITARY HYGIENE. and its neigkbor one highly contaminated. This point should not be overlooked in the respective location of wells and latrines or other sources of pollution. Where pollution of a well from a latrine or similar source of contamina- tion is suspected, a large amount of salt dissolved in a considerable bulk of water may be poured into the vault and the water in the well repeatedly examined quantitatively for chlorides. Many color- ing substances have also been employed for this purpose, and among these fluorescin and methylene blue have been found to be the most satisfactory. According to TriUat, fluorescin may be detected in a strength of one part in two billions of water. All colors are removed by peat. Clay and sand let colors pass freely, but humus and garden sou retain aU but fluorescin and acid fuchsin. The yield of wells can be determined only by lowering the water to a certain level and noting the length of time required for refilling, as well as measuring the quan- tity removed; the complete removal of the water is unnecessary for a sufficiently ac- FiG. 16.— Method oi sinMng Temporary curate estimate in this rcspect. Well for Camps, Showing Portable __„ , ^ , ■-,-,, Pump and Filter. Where the water supply, especially for encampments, must be derived from existing wells, a careful inspection of their character, and particularly of their sur- roundings, should be made. The water of those located in the vicinity of refuse heaps or privy vaults should be carefully avoided. It is said by Bashore that in the state of Pennsylvania the proportion of typhoid fever is fifteen times greater in the country districts than it is in cities ; this being explained by the fact that the population in the former case is obliged to depend upon well water, drawn from ground water often infected from privies which at one time or other have contained typhoid excreta. Unless properly protected at the top, weUs are liable to con- Wo,tej- Leval .^.:i0' i - Water Levfe^, ■^ *^ Jit-reeiio-n. of flow of «H.bjoi.l Wund, a bhuHh tint is ac- jquired. Many excellent waters are grayish, and a few. — as an instance, that of the Dismal Swamp, formerly much prized on board ship — are diHtinctly brown. Greenish waters usually owe their color to vegetable matter, chiefly unicellular algaj, and are ordinarily harmless. Yellow and light brown waters are most to be feared, as their color is usually due to organic matter, too frequently sewage. These tints may, however, be due to iron salts, although in most cases the iron is precipitated from solution in the form of ferric oxide. Clearness. — ^Where the water is of good quality it is usually trans- parent and limpid, but it frequently happens that water of otherwise ex- cellent character contains considerable earthy matter in suspension. Such waters are readUy clarified by sedimentation ; this process und()ul)tedly re- sulting, as already stated, in the mechanical carrying down of a consider- able proportion of the bacterial organisms present. Occasionally it hap- pens that water remains hazy or turbid even after standing foi- some time, the suspended matter in such case being in a state of very Hn^ division. With reference to the influence of suspended mineral matter upon health there is some diversity of opinion. It is an niniuestioned fact that very turbid water is habitually used by large communiticM with no demon- strable evU effects, but the preponderance of testimony goes to show that immunity is attained by continued use, and that tlie stranger in this re- spect is not upon the same plane of safety with the native. J*iirl¥A^ ^^^Xt- ■- - e, o, ,_ ''/;,> " -; v^y i^ _j/ii i»,jj/' COMMONER AND MORE IMPORTANT FORMS OF MI0RO8GOPI0 LIFE IN WATER. 1. Diaptomus. (X 35.) 5. Cyclops. (X 35.) 3. Gladothrix, showing false branching. 6. Bosmina. (X 35.) (Much enlarged.) 7. Anguillula. (X 100.) 3. Beggiatoa. (Much enlarged.) 8. Uroglena. (X 250.) 4. Daphnia. (X 35.) 9. Canthocamptus. (X 35.) WATER. 135 Fig. 22.— Mlquel's Flask. sterilize their contents. Gelatin tubes thus prepared should be kept stored in the dark, their wool stoppers being covered by rubber caps to prevent evaporation and concentration. Gelatin-peptone should be made in but small quantities, since old jelly has a tendency to become acid in reaction, which is unfavorable to the growth of certain forms of bacterial life. It is obvious that bacteriological examination of water is valueless un- less made promptly upon samples which have been collected with every precaution against contamination. Miiltiplication of bacteria goes on with extraordinary rapidity at ordi- nary temperatiues, and when possible, the inoculation of cultiffe media should be performed at the source from which the water is drawn. This can be done by the use of Miquel's conical flasks, which have flat bottoms and tubulated glass caps, ground at the joint, plugged with cotton. Such flasks receive 10 c.c. each of the nutrient gelatin when it is first made, and are kept in stock like test tubes. Taken to the field, they receive an inoculation of 1 c.c. of water, and the chances of later contamination by transfer, and of multiplication during the journey to the laboratory, are thereby avoided. Water samples are taken by many in small glass bulbs with long thin stems. These bulbs can be sterilised by the direct Bunsen flame and sealed while hot. Upon afterward break- ing off the point of the stem imder water, the latter will enter the vessel because of the partial vacuum and the stem can be at once sealed in a candle flame. During transportation to the laboratory the bulbs fiUed with water samples should be packed in ice. Upon arrival at the laboratory the base of the stem is partially cut through and broken off. After agita- tion of the water, 1 c.c. is transferred, by means of a sterilized pipette, to a test tube of nutrient gelatin, the jelly having pre- viously been liquefied by immersion of the tube in warm water and the cotton plug having been singed in the Bunsen flame. Mixing of the water and gelatin is accomplished by tilting the tube forward and back, and the mixture is then poiured into a sterilized Petri dish, and incubated, in the dark, at a temperature of about 22° C. Where the water contains a large number of micro-organisms it is advisable to make several cultures with different dilutions. This is usually accomplished by sowing one tube of nutrient gel- atin, for purposes of comparison, in the manner already given. Inoculations are then made in the same manner from a mixture made up of 1 c.c. of the water under examination and 9 c.c. of ster- ilized water ; and also from a mixture containing 1 c.c. of the water sample and 99 c.c. of steriUzed water. These dilutions must be made with great care, since any error is multiplied. Counting of the colonies of bacteria is usually undertaken after an in- cubation period of forty-eight hours, but this period varies according as there is greater or less danger of the colonies coalescing and thus confus- /] Fifi. 23.— Bulbs for Water Samples. 136 THEOKY AND PRACTICE OF MILITARY HYGIENE. Fig. 24.— Improved Apparatus for CountiDg Colonies of Bacteria. (After Mason.) ing the count. It is assumed that each colony is the result of the develop- ment of a single micro-organism, and from the enumeration of these colonies the amount of bacterial life in each cubic centimeter — taking the various dilutions of the water sample into consideration — may readily be deter- mined. It is the practice of some to use high dilutions, to continue the in- cubation for a period of two or three weeks to allow the development of the more slowly developing bac- teria and to coimt only such colo- nies as are then perceptible to the naked eye. This method of pro- cedure has many advantages. Where the number of colonies is large, counting must be done with the aid of a ruled glass plate. For this purpose a modification of Wolffhiigel's apparatus is rec- ommended by Mason. The number of micro-organ- isms found in different water samples varies greatly, not only according to their degrees of purity but also according to season and, as intimated above, the length of time they have been kept before examination. It is difficult to lay down any standard of bacterial pinity for drinking-water, in terms of permissible numbers, as the power of micro-organisms for evil plainly depends not so much upon their quantity as upon their special character. "It has been asserted that the presence of a large number of micro-organisms is no cri- terion of the quality of a water, and that the mere enumeration of colonies is of little or no value. Without a thorough knowledge of all the accom- panying conditions such knowledge is certainly insufficient ; though speak- ing in a general way, it may be accepted that numerous bacteria indicate the existence of a sufficient quantity of food which, in water, is commonly of the nature of sewage." Besides the positive evidence which it gives regarding the conditions favorable to the existence of germ life in water, pathogenic as well as saprophytic, the bacteriological examination of water has a special value in testing the efficiency of the Berkefeld filters used in the military service. For this latter purpose the cultivation and coimt of germs is most valuable and differentiation is a secondary matter; for the assumption is a just one that a filter which removes the harmless bacteria will eliminate the patho- genic varieties as well. Among natural waters a sample which contains but 100 bacteria per cubic centimeter is usually regarded as very pure, while water containing up to 500 per cubic centimeter is usually classed as good. When con- taining 500 to 1,000 micro-organisms per cubic centimeter a water may justly be regarded as suspicious ; while very impure waters contain from 5,000 to 50,000 germ per cubic centimeter. WATEE. 137 III. PURIFICATION OF DBINKIN|' - "■■■-V Fig. 46.— Battery of Pasteur-Chamberland Filters as Used In the Frencb Army. often be a matter of the greatest difficulty. During cold weather due care must be given these filters to prevent their injury by freezing. It is obvious that to store filtered water in an unclean receptacle, or to mix it with xmfiltered water, is to destroy the special advantage of filtra- tion by the Berkefeld or Chamberland apparatus. Purification by Chemical Means.— While the unhealthfulness of a water is probably rarely due to mineral matter held in suspension, the clarification of a turbid water wiU at times be desirable. Where filters are not available such waters may be cleared by sedimentation, the process being materially aided by the use of alum. In China, the removal of sus- pended matter is thus commonly effected; the natives stirring the water to be clarified with a small bamboo pierced with holes and containing this substance. In general, the proportion of 6 grains of alum to the gallon of water is sufficient. The method is most satisfactory when calcium car- bonate is present in the water, and if this be absent the addition of a little 152 THEORY AND PEACTICE OF MILITARY HYGIENE. sodium carbonate prior to the use of the alum is advisable. The carbonates present ia the water readUy decompose the alum with the formation of a white gelatinous precipitate of aluminum hydrate ; this, together with cal- cium sulpliate, entangling suspended particles and carrying them down to the bottom. The reaction, where the carbonate of calcium is concerned, is as foUows : K„ Al, (SO,), + 3 CaC03 + 3 H, = 3 CaSO, + K, SO, + 3C0, + Al, (OH), The time required for the sedimentation of water treated with alum is short, and the clear fluid which may soon be decanted off may be further purified by boiling or filtration. The deposition of the earthy matter held in suspension mechanically removes, also, a varying proportion of organic matter and bacterial life. In general, the more turbid the water the greater the proportion of germs carried down during clarification. De Santi and Lejeune found that most of the bacterial life was removed by alum, and Babes went even so far as to state that a proportion of one to five thousand is sufficient to sterilize drinking-water. Teich, however, found that it was extremely difficult to remove all micro-organisms by this method, and states that alum appeared to have no directly germicidal properties — the typhoid bacillus not being destroyed by a strength of one to three thousand, while the vitality of even as low a resisting germ as the cholera vibrio was not affected during an ex- posure of twenty-four hours. The long continued use of alum water is said to induce digestive dis- turbances, and its employment as a means of purification is quite inferior to modern methods of filtration. It has, however, a practical value for field use in the absence of suitable filtering apparatus. Where necessity requires the use of an extremely hard water it is often advisable, even in the field, to institute measures for its correction, at least in limited quantity. Vegetables cooked in hard water turn yellow, and beans and peas shrivel and harden. Meat boiled in hard water becomes tough and indigestible ; while the use of such water for washing purposes is wasteful of both soap and labor. The common cause of hardness of water is due to the presence of calcium carbonate and also of the sulphates of calcium and magnesia. In pm'e water, calcium carbonate is soluble only to a very slight extent, but in water which holds free carbon dioxide in solution, one pound of calcium carbonate can be dissolved in five hundred and sixty gallons of water by seven ounces of the gas. It is also soluble in water from an almost opposite cause — by driving off the carbon dioxide from the carbonate and reducing the latter to the oxide. In burning one pound of calcium carbonate, seven ounces in weight is lost by the expulsion of carbon dioxide, and the remainder, consisting of nine ounces of calcium oxide, is then entirely soluble in forty gallons of water. Clark's process for removing the hardness of water takes advantage of these facts. The water to be softened is mixed with water containing quick-lime in the above proportions, when the seven omices of free carbonic acid gas, which held the first one pound of calcium carbonate in solution, combines with the nine ounces of quick-lime to form one pound of calcium carbonate ; and this, together with the first one pound of calcium carbonate no longer soluble through the loss of the free carbon dioxide, is precipitated out. This process is simple and convenient, but is more advantageously carried WATER. 153 out on a large scale. In the precipitation of calcium carbonate a consider- able proportion of suspended matter is also removed. Hard waters may also, to a certain degree, be corrected by the addition of sodium carbonate. If beans are to be cooked iu hard water a small pinch of soda to the liter of water is usually sufficient, but where the quantity of soda is very great the beans take on an alkahne taste and are reduced to a soupy consistency. Where the water is to be used for drink- ing, the quantity of soda to be added should be determined by chemical analysis. The sodium svdphate so formed is in no way harmful, while the resulting calcium carbonate is precipitated out. Based on the three methods detailed above, Maignen has devised a powder, sold under the trade name of "anticalcaire," for the purification of water. This is composed of a mixture of hme, sodium carbonate and alum ; the relative proportions being made to vary with the character of the water to be purified. Laveran, however, experimenting with this powder, was rmable to effect the sterilization of water, even when the powder was used in the proportion of one to two thousand, although the number of bacteria was markedly reduced and clarification was excellent. It has not been shown that Maignen' s powder can be employed any great length of time without inducing intestinal disorders. A ready method of clarifying water, but available in certain regions only, consists in the addition of "prickly pear " or cactus leaves which have been previously cut up and bruised. The water is preferably allowed to clarify over night. The use of permanganate of potash for the pmification of water, by the oxidation of organic matter, has been advised by SchipUoff and others. No definite strength can be suggested, since the amoimt of permanganate of potash required necessarily varies with the quantity of organic matter to be oxidized. The usual procedure consists in adding small quantities of a strong solution of potassium permanganate to the water to be purified, stirring constantly during the operation. An excess of the reagent is in- dicated by a permanent pink tint, which should remain for at least half an hour before being discharged. The rosy color of the permanganate in excess can best be discharged by the addition of a weak solution of citric acid, or, in its absence, of tartaric acid. Sugar, after inversion by boiling with vinegar, may also be used, but its action is slow and considerable quantities are required. Experiments by the writer showed that 100 c.c. of a .05 per cent, solution of potassium permanganate was decolorized in ten minutes by 10 c.c. of a 1 per cent, solution of citric acid, and by 5 c.c. of the same solution in thirty-five minutes. Using the same strength of permanganate solution, 10 c.c. of a 1 per cent, solution of tartaric acid de- colorized 100 c.c. of the permanganate solution in thirty-five minutes, and 5 c.c. in sixty-five minutes. Chicandard states that water may ordinarily be sterilized by the use of 5 to 10 cgm. of the potassium salt to the liter of water. CoreQ, however, states that as much as 10 to 20 cgm. per liter does not sterilize, but merely reduces the number of micro-organisms. It is probable that these dissimilar results were due to a difference in the amount of organic matter present in the waters examined by these observers. Laveran found that, under ordinary circumstances, a strength of 0.5 gm. to 0.6 gm. of permanganate to the liter could be depended 154 THEORY AND PEACTICE OF MILITARY HYGIENE. upon to kill pathogenic bacteria if the exposure were continued for several hours. One objection to the use of permanganate is that it often communi- cates a yellow tint to the water, arising from suspended finely divided peroxide of manganese. This is probably of no moment as far as health is concerned, but it is unsightly. Sometimes the addition of a little alum will carry down this suspended matter ; boiling may be used, but often has no effect. Sometimes nothing removes it but filtration. Potassium per- manganate readily removes the odor of hydrogen sulphide, and has a spe- cial value in destroying the peculiar offensive odor of impure water which has been kept in casks or barrels. Permanganate of calcium has been suggested by Bordas and Girard for use in connection with the piu-ification of water. On contact with organic matter this substance rapidly decomposes in the production of oxygen, oxide of manganese and lime ; the presence of carbonic acid in the water favoring this decomposition through the affinity between lime and carbon dioxide. The excess of calcium permanganate remaining in the water is removed by filtration through coke and the black oxide of manganese. Schumberg has recently described a method of sterilizing water, by the use of bromine, which appears to possess a special value for the military service. In this method a 20 per cent, solution of bromine is used, thirty drops being sufficient to sterilize a quart of water in five minutes. The bromine is then neutralized by ammonia in the production of ammonium bromide ; thirty drops of a 9 per cent, solution of ammonia being sufficient to exactly neutralize. It is desirable that actual neutralization should be obtained, although a faint taste of bromine or ammonia is not seriously objectionable. In case the water is very hard or foul the bromine may be cautiously added until a faint yellow color is produced. Watt has proposed the use of perchloride of iron for the sterilization of water, this salt being neutralized by calcium hydrate or sodium carbonate. This produces the hydroxide, which, on jsrecipitating, carries down the micro-organisms in suspension. After sedimentation, the water is filtered. The water so obtained is undoubtedly very pure, but the method is open to the criticism of using a salt which is itself corrosive to metals and which, in common use, would not be free from the danger of accidents. It is stated by Christmas that, as far as the cholera vibrio is concerned, water may be as surely sterilized by the addition of 0.6 gm. to 0.8 gm. of citric or tartaric acid, per liter, as by boihng. This proceeding is very simple and may be used with advantage during the prevalence of cholera infection. CHAPTER V. I. THE EATION. General Consideration of Food. — Food is that which, when taken ia the body, builds up tissue, repairs waste or is consumed in the produc- tion of heat and energy. If food be in excess of the requirements of daily consumption it may be stored up, chiefly in the form of fat, for future use. The best nutritive substances are those which perform their function in the most thorough and complete manner; that is, with as little waste as pos- sible and with the best physiological results. They should be digestible and palatable, and, when brought together iu the diet, should furnish in proper alnounts the different substances required by the system. The latter point, ia determiuiag the dietaries of soldiers, is of much importance. It may be assumed that, in general terms, nitrogen and carbon represent the materials required. No single article of the ration, however, yields these substances in the proportion desired. The soldier confined solely to a meat diet would be required to take iuto his system about four times as much nitrogen as would be necessary in order to get sufficient carbon; while a diet of bread alone would overload the organism with carbon be- fore a sufficiency of nitrogen was attained. Foods, from their different chemical composition, are therefore used most advantageously to supplement each other. Food-stuffs are usually classified, according to their proximate com- position, as follows : ( Nitrogenous, as proteids or albuminoids. I.— Organic •< ({a) Pats. ( Non-nitrogenous <(b) Carbohydrates. ( (c) Vegetable acids. TT r „„j„ ( Mineral salts. II.-Inorgamo -j Water. III. — ^Pood accessories, as tea, cofEee and'condiments. The first two classes of food-stuff's are essential to life ; the third class is important as favoring palatability and digestibility. The true nutrients are protein, fats and carbohydrates; and these, within the organism, serve the following general purposes : Protein forms tissue (as muscle, tendon, and fat) " and serves as fuel j Fats form fatty tissue (not muscle) and serve as fuel Carbohydrates are transformed into fat and serve as fuel All yield energy in form of heat and muscular strength. The protein and fats of body tissue are used like those of food. In being themselves burned to yield energy the nutrients protect each other from being consumed. An important use of the carbohydrates and fats is to protect protein from consumption. All foods contain water in considerable 156 THEOEY AND PEACTICE OF MILITAEY HYGIENE. but varying proportion ; and many of them contain considerable material, as the bone of meat and the skins of potatoes, which cannot be employed for purposes of nutrition. In the adjusting of diet to the demands of the body, the important matter is to provide enough protein for the building and repair of tissue, and enough energy to keep it warm and do its work. Considering the body as a machine, there must be material to construct it and keep it in repair, and fuel to supply heat and power. If there is not food enough, or the nutrients are not in the right proportions, the body will be weak in its structure and inefficient in its work. So, likewise, if there is too much, damage to health will ultimately result. The latter con- tingency is scarcely to be apprehended in the military service. While fats and carbohydrates may within certain limits replace each other in the dietary, neither can take the place of protein. A sufficient supply of the latter is essential, and if the income of nitrogen, which is present in food only in protein, be not equivalent to the outgo — ^the amount of the latter varying with the individual and the work to be performed — a condition of inanition, resulting in death if the deprivation of protein be sufficiently continued, is certain to ensue ; although for a time the muscles will carry on work at the expense of their own albuminous constituents. On the other hand a large excess of nitrogenous material in the diet is undesirable ; and it is of advantage if the amount of protein taken in as food can be reduced, through the ingestion of a proper amount of fats and carbohydrates, to about the point required for constructive and reparative purposes alone. Protein is a source of energy, as well as of repair, in the body ; but it is undesirable to employ it for the former purpose, since its oxidation leaves behind a large amount of nitrogenous matter which must be passed out of the organism as an excrementitious body. No constant figure can be given as to the amount of protein which should be taken as food by each individual, but physiologists are agreed that 150 gm. of protein may be regarded as sufficient for the needs of men at such labor as may be required of the soldier. The amount of nitrogen is found by dividing the amount of protein by the factor 6.25. Fats find their use as sources of energy and heat to the body. Fat has a place in all dietaries, its relative proportion in the food consumed being much increased in cold climates. When hard work is to be per- formed fat is also instinctively taken, since it possesses a high calorific and potential value. The amount of fats, consumed by inhabitants of the United States is considerably greater than that used by corresponding classes in other countries of the temperate zone, and our military ration is also far superior to those of foreign armies in respect to its fatty constituents. The consumption of carbohydrates not only spares proteid food but also fat, being utilized in the production of heat and energy. As compared with fats, carbohydrates are a less concentrated, fuel; but they may be transformed into the latter in the body and thus become a reserve source of energy and warmth. The greater proportion of carbohydrates are, how- ever, directly consumed within the body; and excess of carbohydrates, owing to the bulk of the food taken, appears to derange digestion. The inorganic constituents of food, especially water and sodium chlo- ride, play an important part in the dietary. Death ultimately follows de- privation of the two constituents named. THE KATION. 157 An important point with respect to the nutritive value of foods is their digestibility, since it is evident that only such portion as can be re- duced to a condition in which it may be absorbed will be of value to the economy. Much experimental work has been done on this point, and the results obtained may be briefly summarised as follows : 1. The protein of ordinary meats and fish is very readily and com- pletely digested. The protein of vegetable foods is much less completely digested than that of animal foods. Of that of potatoes, whole wheat and rye flour, one-fourth or even one-third may escape digestion and thus be useless for nourishment. Eoughly speaking, one-sixth or one-seventh of the protein of wheat flour, com meal, beans and peas may be assumed to be imdigested when cooked and eaten in the usual way. With inexperi- enced cooks, and especially in the field, a still greater proportion may be unavailable for nutritive purposes through lack of proper preparation. 2. Much of the fats of animal food may at times fail of digestion. This is presumably true of vegetable fats, but the quantities are in general so small that the determinations of the proportions digested are not very accurate. The experiments thus far made imply that perhaps five per cent, of the fat of meats, butter and lard wiU escape digestion as they are ordinarily eaten. 3. The carbohydrates, which make up a large part of vegetable food, are in general very completely digestible. The crude fiber or cellulose is an exception ; but the quantities of this in the materials used for the food of man are too smaU to be of importance. Sugar is believed to be com- pletely digested. The carbohydrates of animal foods are very- small in amount. 4. The animal foods have, in general, the advantage of the vegetable foods in digestibility, in that they contain more protein and that their pro- tein is more digestible. 5. The quantity digested appears to be less affected by flavor, flavor- ing materials and food adjimcts, and to differ less with dijfferent persons, than is commonly supposed. Relation of Food to the Work of the Soldier. — For the military service a knowledge of the potential energy latent in food is desirable in calculating the amoimt and character of the nutritious substances capable of yielding suflicient energy for the performance of a definite amount of external muscidar work ; since force manifested in the living body must be the correlative expression of force previously latent in the food eaten or the tissue formed. This potential energy latent in nutritive material can be measured like heat or mechanical power; and work to be done may be calculated in foot-tons, which can also be readily expressed in terms of food or foods. In practice, however, such a calculation is not exact and is only of relative value, since the mere expression of potential energy cannot exactly fix a dietetic value which may be dependent on conditions of the body imknown to us. Experiments made by Helmholtz seem to show that this external work should be one-sixth to one-fifth of the mechanical force latent in the digestive food, but conditions must be very favorable to obtain this proportion, and in practice probably only one- sixth to one-seventh may be expected. It is obvious that, given a definite amount of nutritive fuel capable of conversion into heat or energy, the re- 158 THEORY AND PEACTICE OF MILITARY HYGIENE. quirements of the system would be greater, in respect to the former, in a cold climate than in a warmer one, and the energy available from the com- bustion of this food would be proportionately diminished by the greater expenditure for heat. Hence a diet sufficient for the accomplishment of a certain number of foot-tons of labor in the United States should properly be increased for troops performing the same amount of labor in Alaska or along the Canadian border — or could be safely diminished for tropical service. The unit commonly used for the measurement of the fuel value of food is the large calorie, this being the amoimt of heat which would raise the temperature of 1 kilogram of water 1° C, or 1 pound of water 4° F. The same word " calorie " is used also to designate the heat required to raise the temperature of 1 gm. of water 1° C. The large calorie is usually spelled with a capital "C," and represents 1,000 of the small calories. In this work the large Calorie only will be employed. The English heat imit is sometimes used in calculating diets ; this being the amount of heat re- quired to raise the temperature of 1 pound of water 1° F.,and representing the dynamic equivalent of the power required to raise 772 pounds to the height of 1 foot. Usually, in estimating the potential value of dietaries, the unit of mechanical energy employed is the foot-ton, 2,240 pounds raised through 1 foot, of which the English heat unit obviously equals about one-third. One Calorie thus corresponds to very nearly 1.53 foot- tons. Taking ordinary food materials as they come, the following general estimate has been made for the average fuel value of 1 gm. of each of the proximate of nutrient principles : In 1 gm. of protein there are latent In 1 gm. of fats there are latent In 1 gm. of carbohydrates there are latent Foot-tons of energy. These figures mean that when a gram of fat, be it the fat of food or body fat, is consumed in the body, it will, if its potential energy be trans- formed into heat,. yield enough of the latter to warm 9.3 kilograms of water 1° C, or 4 pounds of water 1° F. ; or, if it be transformed into mechani- cal energy, such as the muscles use to do their work, it wUl furnish as much as would raise 1 ton 14^ feet, or 14^ tons 1 foot. A gram of protein or carbohydrates yields a little less than half as much energy as a gram of fat. Using the above figures and knowing the percentage composition of the articles of the rations — as given later — the amounts and proportions of the food theoretically required to furnish the energy for any given amount of external muscular work can readily be calculated. For practical appli- cation, however, it is necessary to know about the amount of external mus- cular work performed by the soldier under various conditions — ^the average limit of human endurance for adult males being generally put at about five hundred foot-tons, during the twenty-four hours, in temperate climates. The expenditure of this great amount of energy, however, could not be con- tinued any great length of time. Assuming the principal work of the soldier to consist in marching, walking at three miles per hour, as stated elsewhere, is equivalent to raising one-twentieth part of the weight of the THE RATION. 159 body through the distance walked. Using this calculation, and assuming the soldier with his clothing to weigh one hundred and sixty pounds, the following figures are obtained for the energy required in marching on level ground : Work done in tons luted one foot. IVIarching one mile 18.86 " two miles 37.72 " ten " 188.60 twenty " 377.20 " one mile and carrying sixty pounds 25.93 two miles " " " " 51.86 ten " " " " " 259.93 twenty" " " " " 518,60 In practice, however, the ground over which the soldier marches can- not be regarded as level, while the weight of the accoutrements is rarely adjusted correctly. Military drill without arms is estimated by Hickman as being one-third more fatiguing than ordinary walking, and four hours' drill for recruits as being equivalent to the daily work of the ordinary agricultural laborer. The duties of the soldier outside of marching are very various and obviously cannot all be, in practice, reduced to exact figures in foot-tons. In general, however, the daily output of energy may be estimated with sufficient accuracy by comparing the muscular exhaus- tion resulting from any task with the labor expended in marching, as cal- culated above. Taking all things into consideration, three hundred and fifty foot-tons may be accepted as a fair estimate of the average day's labor which may be performed by the soldier. In considering the amount of food required, however, a certain excess over the quantity sufficient to furnish energy for the accomplishment of these three hundred and fifty foot-tons of work should be allowed, since there should be a certain amount of reserve force upon which the soldier may draw during unusual trial and hardship. Exactly how much food is considered by physiologists to be required by men performing hard manual labor, equal to that de- manded of the soldier, and what its proximate character should be, is con- sidered subsequently. Requirements of the Soldier's Dietary and Ration. — The con- ditions governing a perfect dietary may be considered to consist in : 1. The determination of the real nutritive wants of the body imder different labor and climate. 2. A proper selection of food as regards quality, nutritive power, ap- petizing property and digestibihty. 3. The association of foods in such wise as not to offend the appetite or burden the digestive powers. 4. A right treatment of nutritive substances by cooking, so as to ren- der them most useful to the system. 5. A jnst distribution of the daily diet in appropriate meals. These conditions especially apply to the soldier, who, considered as a machine, must be kept in good repair and supplied with sufficient motive power. A deficiency in nutritive material means diminished vital resist- ance and impaired strength, which for a time incapacitates the individual and renders him unable to fulfil his duties. It is most important that work done by the soldier should be evolved from the food taken and not 160 THEORY AND PEACTICE OF MILITAEY HYGIENE. from the tissues of the body, since sickness will otherwise ultimately result. Only in great emergency, and then but for brief periods, should the tissues be called upon for the production of energy. As to the special qualities of the military ration, m addition to pos- sessing adequate nutritive value, its components should be sufficient ia number to afford a reasonable variety to. the food consumed by the soldier. They should also be easy of preparation. Since troops must often be fed at considerable distances from the point of supply, it is evident that the articles included in the ration must be readily transportable and easily pre- served. Bulky articles offer obvious disadvantages, and hence the ration Nutritive mgredients, refuse, and fuel value. Untrients. Non-mitrieDte. Froteio.) Fats, Carto-* Mineral bydrates. matters. Water. Eofuae. Fig. 47.— Proportionate Composition of the Chief Food Materials Entering into the United States Army Ration. CAf ter Atwater.) must largely be dry; but, on the other hand, a certain amount of fresh food is necessary to health. Coupled with these requirements, the nutri- tive' substances must be so inexpensive as to refute any charges of extrava- gance, and must be articles abundantly produced and commonly consumed within the limits of the state. From the circumstances of the case, the character of the food available for use in the field in time of war is neces- sarily somewhat different from that issued in garrison in time of peace. Quantity of Ration.— In the United States army the nutrition of the soldier depends on the allowance of food — or ration — provided at govern- ment expense ; on the additional food purchased from the funds accruing from the post exchange and the disposal of salable property ; the food pur- chased by the soldier from his private resources and eaten by him at the post exchange or other resort; and the food furnished by post gardens and by huntmg and fishing parties. Of these, the first is by far the most im- THE EATION. 161 portant, the other sources of supply being merely supplementary to it and by no means constant. Particularly is this the case in the field, where a liberal supply of nutritive substances is most desirable and yet where the means of supplementing the ration by gardens, exchange dividends or per- sonal outlay is naturally wanting. The ration by itself, therefore, should supply to the soldier a quantity and variety of articles of food which, under proper manipulation, should yield dietaries of moderate nutritive value for the routine duties of garrison life or should be capable of furnishing suffi- cient energy and of repairing body waste under any of the conditions under which troops may be forced to campaign. Nothiag should be left, with regard to food, to chance or opportunity. Insufficient nourishment directly disposes to disease by lowering the powers of vital resistance ; and from the economic view a weak, under-fed soldier is no soldier, costing the na- tion to support him more than his services are worth. Particularly in the field must the allowance of food be liberal. The average appetite of the command is the theoretical measure of this allowance, but in practice this should be exceeded to afford a margin or surplus for contingencies. Over- feeding may have its dangers, but these are scarcely to be dreaded in the military service. Armies have been disarmed by a deficient dietary, but never by over-feeding consequent on the establishment of a liberal ration. Bearing these facts in mind, it is important to gain an understanding as to the sufficiency and composition of the ration supplied the soldier, both with regard to its individual components and as a whole. The following table, compiled from data elaborated by Atwater and Bryant, shows the quantities, chemical composition and nutrient values of the various articles of the ration as at present issued in our service : Quantities per ration, ounces. Amounts Present in Ration (Grams). III Articles ol Ration. 1 S 1 il H Fresh beef (fore and hind quarters) Or Fresh mutton 30 30 13 13 22 14 18 18 16 18 18 16 30 2f 1| 3f 1| 16 16 16 3 83.35 93.4 55.08 31.38 88.6 63.53 40,8 70.90 88.43 55.08 48.45 65.7 50.4 15.16 3.5 16.38 3.69 9.5 8.6 8.16 1.18 13.3 14.7 8.8 4.99 14.16 10.16 6.5 11.18 14.14 7.9 6.9 10.44 7.99 3.43 .56 2.62 .59 1.52 1.4 1.30 .19 89.5 125.8 225.08 210.12 142.3 1.59 1.02 108.14 34.00 5.6 6.13 5.9 13.4 1.22 .18 .75 .27 .45 .73 .58 1.03 380.46 369.38 330.5 435.8 40.18 35.55 41.8 85.5 81.7 73.09 63.59 33.8 1,180 1,440 Pork 3,187 3,085 Salt beef 1,584 Dried fish (cod) . 276 155 Pickled fish (mackerel) 1,039 680 Flour 1,850> Or Soft bread 1,355, Hard bread 1,712 Cornmeal 1,986, Beans 240. Or Rice 163; Peas 246; 173; Potatoes 380 Or Potatoes 80 per cent. , and onions 20 per cent 340 Potatoes 70 per cent., and canned tomatoes 30 Der cent 397 Dried fruits (average of varieties issued) 147 11 162 THEORY AND PRACTICE OF MILITARY HYGIENE. Articles of Bation. Sugar Or Molasses Cane syrup CoflEee, green Or Coffee, roasted Tea, green or black Vinegar Salt Pepper Baking powder Soap Candles Amounts Pkesent in (Grams). ElATION ^^^ Quantities per ration, ounces. I g i 2* M gill- % A^ii- .... .... 64.6 41.25 41.36 364 198 198 __ Prom the above table it is at once apparent that the ordinary variation of the articles composing the food of the soldier, as contemplated ia the establishment of alternative components of the ration, does not furnish dietaries of the same proximate composition or nutritive value. Using the figures just given, the proximate composition and nutrient value of the maximum quantity of food material which may be drawn as a daily alLow- ance by the United States soldier are seen to be as follows : Articles. Quantity in ounces. Fats, grams. Carbo- hydrates, grams. Protein, grains. Nitrogen, grams. Fuel value. Calories. 20 18 3.4 16 2 3.4 89.50 . 5.60 1.32 .45 1.02 380.46 40.18 81.70 33.80 64.60 83.35 55.08 15.16 9.30 1.18 13.30 7.90 3.43 1.53 .19 1,180 Flour 1,850 Beans 340 380 Dried fruit 147 Sugar 264 Total 60.8 97.79 600.74 164.37 35.33 4,061 Total carbon, 437.03 gm. ; nitrogen to carbon, 1 : 17. In the followiug table are included those articles of food which, taken together, may be considered to constitute the ordinary ration for troops in the field or during active campaign. No fresh vegetables are considered ia this dietary. Articles. Quantity In ounces. Fats, grams. Carbo- hydrates, grams. Protein, grams. Nitrogen, grams. Fuel value, Calories. Bacon 13 16 3.4 3 2.4 310.12 5.90 1.22 1.02 33d.5b 40.18 33.80 64.60 31.28 65.70 15.16 1.18 4.99 10.44 3.43 .37 2,085 1,713 240 Beans . . Dried fruit 147 Sugar 264 Total 34.8 318.26 489.08 113.33 18.13 4 448 Total carbon, 432.78 gm. ; nitrogen to carbon, 1 : 33.8. THE RATION. 163 A selection of food-stuffs contained in the ration commonly employed by troops in garrison is given in the following table, but to the figures yielded by them must in practice be added those for whatever additional foods might be purchased from the savings in flour, beans and other articles, possible with this dietary : Articles. Quantity In ounces. Fats, grams. Carbo- hydrates, grams. Protein, grams. Nitrogen, grams. Fuel value. Calories. Fresh beef 20 18 16 2 3.4 89.50 6.13 .72 1.02 269.28 73.09 33.80 64.60 83.35 48.45 8.60 1.18 13.30 6.90 1.40 .19 1 180 Soft bread 1,355 340 147 • Potatoes and onions Dried fruit Sugar 264 Total 58.4 97.36 '440.77 141.58 31.79 3,296 Total carbon, 344.57 gm. ; nitrogen to carbon, 1 : 16.3. In the following dietary a combination is given in which a full daily allowance from each component of the ration is included. This dietary represents the least amount of nutritive material which can be drawn by the United States soldier; but to it, as in the previous instance, shotdd be added the additional articles of food which would be purchased from the sav- ings on flour, coffee and vinegar, thus considerably increasing its nutritive value. Articles. Quantity in ounces. Fats, grams. Carbo- hydrates, grams. Protein, grams. Nitrogen, grams. Fuel value'. Calories. Fresli fish (cod, whole) . . . 18 18 1.6 16 2 3.4 1.02 6.12 .18 .54 1.02 269.38 35.55 65.80 33.80 64.60 40.80 48.45 3.50 8.17 1.18 6,50 6.90 .36 1.36 .19 155 1,355 Eice 163 Potatoes and tomatoes . . . Dried fruits 297 147 Suear 264 Total 56 8.88 409.03 102.10 15.51 3,321 Total carbon, 341.84 gm. ; nitrogen to carbon, 1 : 16.7. In considering the sufficiency of the ration the maximum allowance which can be drawn, as given in the first dietary, wiU alone be of impor- tance ; and this should be compared with accepted dietary standards as determined for the correspondrag laboring classes in civil life. These are variously given by Atwater, for different countries, as follows : Active muscular labor. Atwater (Amer ican standard) Men at hard work. Voit (German standard) Active laborers. Playfair (English standard) Protein, grams. Fats, grams. 150 150 145.13 99.77 154.19 73.56 Carbohydrates, grams. 500 448.96 566.87 Fuel value, Calories. 4,060 3,370 3,630 164 THEOEY AND PEACTICE OF MILITAEY HYGIENE. On comparing the American standard proposed by Atwater with the combination of components of the ration given in the first dietary, noted above, it is seen that the fuel value almost exactly corresponds in both. The fats are somewhat deficient in the ration dietary, but the carbohydrates and protein are in excess. Ordinarily in our service, however, in each ten days there are seven issues of fresh meat and three of bacon and pork. This makes a considerable change in the character of the dietary ; and, sub- stituting the average figures of the beef and bacon issues for those of beef alone, the nutrient value and composition of the maximum food allowance for the soldier is seen to be as follows : Protein, grams. Fats, grams. Carbohydrates, grams. Fuel value, Calories. 152.79 134.97 600.74 4,333 This dietary has a force-value somewhat higher than the standard men- tioned above, and the carbohydrates are also in excess. The deficiency in fats is but slight, while the amount of protein is seen to be almost exactly the theoretical normal for this country. As a whole, and in each of its proximate principles, the United States army ration is much superior in nutritive value to the allowance of food which is regarded by foreign au- thorities as quite sufficient for the needs of men at hard labor in England and Germany. As shown by the above figures, the food-value of the ration is in con- siderable excess of the nutritive material found by Atwater to be actually eaten in the training diets of the Yale and Harvard University crews dur- ing the hard labor of the racing season of 1898, These diets gave the fol- lowiag average : Protein, grams. Fat, grams. Carboliyarates, grams. Fuel value. Calories. 155 177 440 4,085 From these and numerous similar results it may be fairly accepted that according to American standards of diet, which are much higher than those obtaining abroad, the United States army ration is somewhat more than sufficient to meet all the demands of active muscular labor in a temperate climate. That this is, indeed, the case is shown not only by comparison of the ration with the above standards, but also by long practical and satisfac- tory experience with its use in garrison and in the field, and the fact that recruits subsisting upon it gain largely in weight and attain a high degree of physical development. As shown later, the standard ration is in excess of the physiological needs of the soldier on tropical service, but, on the other hand, it is undoubtedly insufficient for service in the far north. Atwater' s more recent investigations place the American standard for ex- hausting labor at forty -five hundred Calories. Hence for a continuous win- ter campaign of arduous nature the ration could with advantage be slightly supplemented by special issues, varying in quantity according to circum- stances. In such instances the additions should be chiefly in the line of an increase in protein and fats, especially the latter, as expressed in the beans and bacon components. THE EATION. 165 In connection with the question of the sufficiency of our ration the fol- lowing analyses of the several rations of the German army, as given by Atwater, are instructive: German army. Protein, grams. Fats, grams. Carbo- hydrates, grams. Fuel value. Calories. Nutritive ratio (protein to energy). Ration, peace footing 113.37 136.05 190.47 40.81 58.95 45.35 480.71 489.78 676.71 3,800 3,095 3,985 5.0 Ordinary ration, war footing. . . Extraordinary ration, war footing 4.6 4.1 ■ From this it wiU be seen that even the maximum German ration is quite inferior to our food allowance except in the matter of protein, and in this respect the German ration is undoubtedly unduly high. It is of interest to note, also, the limited quantities of food under which troops can perform efficient military service. According to Dunlop, the food value of the rations issued to British troops lately besieged in Lady- smith, South Africa, yielded but 73.4 gm. of protein, 69.7 gm. of fats and 141.6 gm. of carbohydrates. The fuel-value of this ration was but 1,527 Calories. This diet is extremely small, being even less than prison or poorhouse diets for persons at rest, yet it furnished a sufficient supply of energy for a stout and successful resistance, extending over a considerable period. Of course the performance of hard marching with such a dietary would have been quite impossible. In this connection it may be remarked that while some men eat more than others at aU periods of their lives, it is an almost universal rule that the young and growing eat and require more food than do those whose development is complete. The same applies also to such as have been long under-fed before their enlistment. The gluttony of men recently enlisted is a constant source of surprise to old soldiers, and it is well to give such immature recruits the desired sense of fuUness by the liberal supply of bulky vegetable foods. For such men to eat of concentrated foods to satiety is to invite sickness. Quality of Ration. — While the quantity of food supplied to the sol- dier is defined by regulations, its quality is largely dependent on the effi- ciency of the Subsistence Department and its preparation for use lies with the consumers. It is obvious that quahty is a factor of the greatest impor- tance, since an inferior character of supplies means that the soldier does not receive subsistence of the nutritive value to which he is entitled. The various methods for the determination of quality in the articles of the ration are detailed in the special mention given them subsequently, and it will here be only remarked that the issue of stores as far as possible in the order in which they are received, as required by existing rules, will often result in the sale of articles which have undergone certain deterioration ; fresh articles lately received in stock perhaps remaining in store to their detriment untU their time for issue arrives. This plan undoubtedly results in a saving to the Government, but is not always to the best interests of the soldier. To limit the bad effects of this rule it is desirable that the supply of perishable articles, as kept on hand by the commissary, should be suf- ficient for a period of not more than one month. 166 THEORY AND PRACTICE OF MILITARY HYGIENE. Variety in Ration. — Variety, in food, is craved by all. However good a single article may be in itself, its continued and exclusive use for any length of time is sure to inspire distaste and consequently to impair its nutritive value. Nutrition depends on assimilation, and assimilation on the tone of the digestive tract, manifesting itself in taste and relish. Mal- nutrition arises from sameness of diet almost as surely as from deficient quantity, and the character of the organic tissues requires that their repara- tive material be gathered from many soiirces ; the distaste and loss of appe- tite which follow the use of an imvaried dietary, however well arranged it may be as to its carbonaceous and azoti^ed proportions, shows that it does not fulfill all the requirements of the system. The company officer should therefore use every effort constantly to vary the diet of his men, bearing in mind that by this means he secures the proper nutritive elements, in due proportion, in the surest and most economical manner. The army ration is uniform throughout the country regardless of local- ity, climate or duty. Manifestly it can be exactly suitable only within very narrow conditions, if indeed perfectly to any. Bearing in mind that in tropical countries carbohydrates form the staple, while a mixed dietary is used in temperate climates, and fuel foods, or fats, are required imder low temperatures, the diet of troops should be suitably modified in these respects according to their geographical distribution. It is obvious that special regulations for soldiers' fare cannot be promulgated to suit each lo- cality and circumstance ; and, with intelligent supervision on the part of officers, these are quite unnecessary. The alternative portions of the ration give it a wide range, which may be further increased by the exchange or sale of surplus parts and the purchase of other foods with the accruing funds ; and the proper selection of these should be the constant study of the company officer. In addition to those of climate, the physiological requirements of the system, dependent on duty or season, should also be given consideration. In the field, variety in food is necessarily restricted as compared with garrison life — depending chiefly upon difficulty of supply, but also to some extent on the inefficiency of cooking utensils. The nearer the camp to a base of supply, or the more permanent it is, the more easily wOl the food be approximated to what is used in garrison. Since a certain degree of sameness necessarily attaches to the most liberal government issue of food, any method which enlarges the scope of its nutritive qualities is valuable. Experience shows that variety of cook- ing answers many of the purposes of variety of diet, and the necessity for a good cook in the company kitchen is obvious. Simplicity in preparing food by no means militates against a certain degree of variety ; and it may be expected that a cook who provides but one dish for a meal will prove expensive and unsatisfactory. A temporary change of cooks, from time to time, is often of benefit, since it brings into use varied methods of prepara- tion; and constant supervision of the bills of fare, on the part of company officers, will tend to neutralize the tendencies of the kitchen to fall into routinism. This question of variety in cooking, important as it is now conceded to be, was long completely disregarded in most armies, our own being some- what better off in this respect. Until as late as 1886, variety in cooking was not prescribed in the French army; and, until 1850, soup made of THE EATION. 167 beef, bread and vegetables was the only food served to French, soldiers at each of their two daily meals. This monotony of preparation was said to have done much to prevent a proper utilization of the ration. As late as 1857, testimony before the committee ravestigatiag into the condition of the British army showed that at that time a company was provided with two boilers, in one of which the men boiled their meat and in the other their potatoes. A soldier ate this diet from the date of his enlist- ment to his discharge; living on boiled meat, if he completed his service, for twenty-one years. Although the meat ration was scarcely adequate, a large portion was imused, as the men became sickened at the monotony in its preparation. There was no means of cooking the ration except by boil- ing. Before leaving this subject it may here be emphasized that an abun- dance of properly varied, well-cooked food does much to promote content- ment among troops. The palatability of his food is no less important to the soldier than to others, and attention bestowed on the company mess has no small influence in preventing dissatisfaction and desertions. Wastage of Ration. — When proper economy in its administration is secured, the quantity of the authorized ration is sufficient. Through indifference on the part of the company commander, and with ignorance or lack of judgment on the part of the cook, the wastage of the ration may be so great as to bring its sufficiency into question. With raw soldiers, inexperienced officers and untrained cooks, as found in the volunteer forces, the wastage of the ration is often serious in this respect. A certain amount of loss is ima voidable — such as is due to the rotting of vegetables, their paring for the table or the presence of bone in meat — ^but outside of this, where there are efficient cooks, the kitchen waste should contain practically nothiQg of any food value to the soldier. Not only should every effort be made to prevent unnecessary loss in cooking, and to utilize all residues, but care should be had in the mess hall, while allowing sufficient food, to take all precautions against' issuing portions larger than will presumably be utilized. Small portions, repeated if desired, should be the rule. The small amount of refuse left on an individual plate may appear trifling, but if this uneaten excess be left throughout a considerable part of the organi- zation, it may have a food value equal to that of a number of full rations. Great care should be taken to preserve aU grease and drippings. Such can be largely used in the preparation of food and gravies, and any excess is ordinarily salable. In one regiment in the British service it was found that the grease thrown out by the kitchens had an annual money value of nearly a thousand dollars. Bones, too, after being well boiled in the mak- ing of soup, have a commercial value. Woodruff estimated that, for a regimental post in Montana, the financial loss per year from bones thrown away amoxmted to a thousand dollars. The other refuse should have a value as fertilizer or for the feeding of stock, but in practice there is usually no market for it. As mentioned elsewhere, in some companies this refuse is fed to hogs, but such a practice is to be discouraged for sanitary reasons. In a post having a strength of four hundred and forty men, during a period of ten days. Woodruff found the wastage in the more important arti- cles of the food to be as foUows : 168 THEOEY AND PEACTICE OF MILITAEY HYGIENE. Article. Per cent, of waste. Eemarks. Bacon Pork 1.40 8.00 3.30 33.50 37.09 ) 31.04 \ 33.00 45.00 13.00 Only nine pounds were reported, but this was increased to thiirty-one pounds to include bones, etc. Crusts and small unavoidable wastes. Nineteen and three-quarters bone, two and three-quarters fat and other wastes. Parings and defective ones. Stones and other wastes. Estimated. Bread Beef Potatoes Onions Primes Cabbage Ham A wasteful cook, no matter what his other virtues, is always undesir- able. In the general mess at Jefferson Barracks the civilian head-cook, paid by the mess at the rate of $1,000 per year, was shown to save the mess twice his salary through his superior economy ; while at the hospital of the Soldiers' Home it was recently found that the chief cook effected a saving, over his predecessor, amounting to nearly $150 monthly. In both instances the men lived better than under a more wasteful administration. Savings from Ration. — While no savings are permitted on fresh meat, fresh vegetables or dried fruit, with due economy some other por- tions of the ration will be saved and sold. The quantities naturally vary with different conditions — of which efficient management is most impor- tant. Climate and the nature of the service also have considerable influence in this respect. Ordinarily the cheaper articles wOl be drawn for use, and those of higher cost saved and then- money value turned into the company fund. In many iastances the local market rates are higher than the prices at which articles of the ration are sold by the Government. In such cases the company commander will draw his fuU allowance and dispose of any surplus to best advantage outside the camp or garrison. Most of the savings are made on flour and bacon, with smaller amounts on the other articles of the ration. The allowance of sugar is always required for use ; generally some of the coffee can be saved, tea rarely. The condiment al- lowance is generally in excess. Food purchased from savings must not be regarded as in any way adding to the food aUowahce of the soldier, but as merely replaciag other nutritive substances to the benefit of which he would otherwise be entitled. It may sometimes happen that certain arti- cles are cheaper in the local markets than as supplied by the commissary ; but ordinarily it is not true economy, quality being considered, to purchase outside food of the kiads which may be bought from the Government. In the field, especially during campaign, but little if any savings can be made from the ration ; certainly none are supposed to be made. If they are made, it is questionable whether the commissary will have the purchasable articles on hand, since great difficulty is often experienced in keeping even the articles of regular issue available for troops. In general, the savings from the ration in garrison, under proper administration, will so supple- ment the diet as to supply abundantly all the actual needs of the com- mand, though naturally falling short of luxury. In the field no back rations are issued, and a command must draw its allowance when due or go without. Generally deprived of markets as THE RATION. 169 well as outside sources of revenue, inarching soldiers fare worse for food than those in garrison and at the same time their nutritive requirements are greater. Additions to Ration. — ^In garrison, the additions to the food fur- nished by the Government for the subsistence of the soldier will usually be considerable, and hence the articles and allowances of the legal ration by no means show what is actually consumed. Money is received in varying amounts from outside sources, independent of the savings on the ration proper, and this is almost wholly used for the purchase of such extra articles of diet as may be desired. Woodruff found that in a garrison of four hundred and forty men, during a period of three months, the average daily receipts and expenditures per man were as follows : Prom ration 3.73 cents. From post exchange 3.58 " From other sources 34 " Total receipts 5.64 " Expenditures for extra food 4.11 " These figures, not including the savings from the ration itself, gave an in- crease to the soldier amounting to about one-fifth the value of the author- ized ration. The savings from the ration are wisely not permitted to be used other than for the benefit of the soldiers' fare, and practically most of the money accruiag from outside sources is devoted to the same purpose. Funds of this character should not be allowed to accumulate to large amounts and lie idle, since the soldier is entitled to an early share in the savings or exchange dividends which he has helped to create. On the other hand, a small reserve should be gradually acquired ; so that when troops take the field and are reduced to subsistence on the bare ration, there should be a sufficient fund to permit the purchase of a fair amount of fresh food when it can be obtained. The limits of the company fund should be prescribed in orders, a reserve of $2 per man being sufficient. This sum would permit the daily expenditure of 2.2 cents per capita, out- side the savings from the ration, for a period of three months. Troops will rarely be in the field, and without exchange dividends, for a longer period than this except during actual warfare. The latter contiugency is so infrequently realized, and its probable duration is so completely beyond the powers of human calculation, that any effort to accumulate a large fund better to meet such conditions would not be justified. As to the expendi- ture of the company fund, the mere purchase of articles of food is a simple matter. To do so judiciously and to the best advantage should be the constant study of the line officer, and prove a subject about which he wOl learn to the last day of his service. To this end the nutritive and eco- nomic values of foods, the habits and tastes of the men and the skiQ of the cook in various methods of preparation will all receive due considera- tion. In general, variety will be sought and price and liability to deteri- oration will be fully considered. Cooking of Ration. — Each soldier is supposed to be capable of cook- ing his own ration in a manner consistent with the preservation of health. To assist in obtaining this object an excellent cook-book is issued, but, as 170 THEOEY AND PEACTICE OF MILITARY HYGIENE. a matter of fact, only a small proportion of soldiers receive trainiag to this end. It has been held that traiaed cooks should prepare the ration and that the soldier should merely be required to consume it ; but as in field service every man may be thrown on his own resources for the preparation of his food, familiarity with the simple methods of cooking is clearly essen- tial. Unfortunately it is rarely possible, under the best of circumstances^ to give such general knowledge to all — the cook beiog usually permanently assigned as such, and some of the men, in rotation, being detailed tempo- rarily as his assistants. By this plan the men have the best skill in the preparation of their food that the company affords ; but it not infrequently happens that the best culinary skill available in a command is by no means sufficient properly to qualify its possessor for such a position. To meet this contingency the special enlistment of cooks, with the pay and allow- ances of sergeants, has lately been authorized ; but even this step has by no means insured the results desired. In the British army greater im- portance is attached to this part of the service than with us, and a special training-school for army cooks is maintained at Aldershot. This is an ex- ample which might be followed with great advantage in our own army, particularly with reference to the preparation of the ration under the con- ditions prevailing in the field. Camp life necessarily dispenses with many kitchen facilities and thus diminishes the variety of dishes which may be prepared ; but those retained should be served in perfect condition. The shortcomings of the camp kitchen cannot be considered as a valid excuse for bad cooking, for nothing should be attempted save what can be certainly accomplished with the fa- cilities at hand. While line officers are responsible for the cooking of the ration, its su- pervision and inspection is part of the duty of the sanitary officer. It is. not expected or practicable that the latter shall minutely instruct in cook- ery, but he should have a knowledge of the general principles of that art, and, especially with raw troops, should have the preparation as weU as the quality of the food constantly under observation. Above aU things he should bear in mind that the first duty of a cook, in or out of the military service, is scrupulous cleanliness. Means of Cooking the Ration. — The cooking-ranges, fixtures and utensils that accompany them are provided by the Quartermasters' Depart- ment. Utensils needed for the preparation of food that are not furnished by the Government can be provided by purchases made from the company or mess funds. The range supphed for garrison use is the so-caUed Army Eange No. 4. This does not differ greatly from similar large ranges em- ployed in civil life and requires no description; the same remarks apply also to the kitchen ware and mess crockery. In the field the conveniences for cooking are greatly varied, ranging from the portable cookimg-outfits, nearly equal in completeness of equip- ment to the kitchen in garrison, to the open fire over which the soldier pre- pares his bacon and coffee with the utensils carried on his person. Vari- ous portable stoves, ranges and ovens have been placed on the market and several varieties are used in our service. Lately, however, the Buzzacott outfits have been accepted as standard for the military service, and these are now bemg generally issued to troops. These outfits are made in sev- THE EATION. 171 eral different sizes and styles. In principle, tlie Buzzacott outfit consists of a steel frame, which serves as a skeleton stove, enclosing a stout rectan- gular oven composed of two sheet iron boxes, one inverted over the other. riG. 48.— Buzza«ott Cooking-Outflt, Paclted. Within this oven are packed a large number of boilers, pans and other utensils, largely on the "nesting" principle, so that comparatively little space is occupied. The outfit is complete for roasting, baking, frying, boiling and stewing, and wiU readily cook for 100 men — and, in an emergency, for a larger number. The roasting capacity is 150 pounds, the broiling or frying 60 pounds and the boiling or stewing capacity 32 gal- lons, or about one barrel. The si^e is 25x35x14 inches; the weight, com- plete, 175 to 200 pounds. In shipping, the skeleton stove fastens about the whole and permits of heavy objects being packed on top without dan- ger of crushing. This cooking-outfit wiU use any kind of fuel and appears well to fulfill every require- ment of field service. It cannot, however, be used except in the open air ; and to meet the needs of troops who may be required to oc- cupy houses, the Buzzacott range, furnished with a stovepipe and built on much the same plans as the cook- ing-outfit, is also supplied. It is of excellent pattern, has a boiling capacity of nearly two barrels, a roast- ing capacity of one hundred and fifty pounds of meat and a bread-baking capacity of twenty -four loaves. Much simpler than the Buzzacott outfits, and correspondingly less sat- isfactory in the results given, is a simple shield for the camp fire made of sheet iron. It is composed of a top and three sides joined by hinges. ^'isshx.^i'-^ ^ Fig. 49.— Buzzacott Cooklng-Outflt In Use. 172 THEORY AND PRACTICE OF MILITARY HYGIENE. Fuel is inserted in front, which should be to the windward ; and being open, any length of wood can be used. A single joint of stovepipe is sufficient. The dimensions of this stove are 30x26x12 inches. It is ob- viously very portable. The Barney steam cooker is also authorized for field use, but is rarely issued. The usual size is 18x24 inches, and when complete it has a weight of 100 pounds. It is made in two sections, one containing a soup or coffee kettle and the other a bakiog-pan. The former has a capacity of 13 gaUons, this being equivalent to 160 cups of coffee or rations of vegetables for 100 men. The baking-pan is said to have a capacity of 75 pounds of meat. The apparatus is operated merely by inserting the legs and placing it over a moderate fire, after pouring water into the steamer. It requires no further attention. Food placed in this apparatus ordinarily requires three or four hours' cooking; it may be kept warm several hours after the fire has died out. The Norwegian stove, used in several foreign armies, is men- tioned elsewhere. Kitchen wagons have been tried in the Austrian army, the idea being to have the food prepared when camp is reached, so that the tired troops would thus be spared the labor of its preparation. The amount of food which it was found could be fur- nished by such a wagon, however, was small; one wagon being re- quired for each one hundred to one hundred and fifty men. The ex- periment was, therefore, with reason abandoned; since the amount of transportation required would great- ly swell the wagon train and corre- spondingly hamper an army. In the absence of any special FiQ.5i.-coiiapsibieSheet:irou stove. cooking-apparatus, the simplest kitchen consists of a trench dug in the direction parallel with the wind, of such width that the kettle, when placed on it, does not project beyond it more than an inch on each side ; its depth should be twelve inches at the end from which the wind is blowing, and continue this depth for four feet. It then decreases grad- ually to three inches at the opposite end, where a space must be left equal Fig. 50. — Buzzacott Range and Utensils in Use. THE EATION. 173 Fig. 53.— Barney Steam Cooker. to the breadth of the trench to serve as a chimney. The fire is estabKshed at the end where the trench is deep; it should not extend beyond three or four feet up the trench. The kettles are placed touching one another; dry sods should be used to stop up the chinks made by the roundness of the kettles, so that the space under them may form a flue. It is advisable to pile up sod, or with stones and earth to erect a chimney of at least one foot in height, at the end farthest from the fire. All grass around the fireplaces should be cut to prevent accidents from fire. If the command halts for more than one day, these kitchens are susceptible of great improve- ment; the chimney can be made of mud, or twigs and mud, and the draft may be in- creased by using short pieces of hoop-iron as bars, stretched across the trench to support a fiUing-in of clay around each kettle. As on the day following the wind may change to an exactly opposite direction, a similar trench must be dug in continuation of the former one — the same chimney beiug used. Tn this manner one chimney wOl serve for trenches cut to suit the wind blowing from all four quarters. The openings from these trenches into the chimney should all be closed with sod, except the one in use. In some places, where brick or stones suitable to the purpose are to be had, it is better to construct these kitch- ens on the gi'ound iastead of below the surface. In the British service the so-called " broad arrow " kitchen is used. It is similar to the- trench kitchen akeady described, but is much more elabo- „ rate and intended for the preparation of food for large bodies of men, regiments rather than companies. It appears to give entire satis- faction. In well-wooded coun- tries, two logs side by side and parallel to the direction of the wind, the fire being kindled between them, make a good company kitchen. Sometimes two logs are laid parallel about three feet apart, two notch- es being cut in each about ten to twelve iuches apart and green logs laid trans- versely in these notches. The fire is built in the centre and the transverse logs give a suitable support to the camp ket- tles. Cranes are buUt by driving two green posts into the ground a foot from the fire. The upper ends, if not terminating in a crotch, should HI _i- Lj VJ ■i^- ,-:-( ^ \A; ^%, VJ VJ VJ VJ \J \J TIANSVEHSE TRENCH 3 SECTION A-B Fig. 63.—" Broad Arrow Field Kitchen, Used In the British Army. 174 THEOEY AND PEACTICE OF MILITARY HYGIENE. be slightly split and a transverse pole with flattened ends inserted in them. Ordinarily the method of improvising a cooking-place consists in ex- cavating a trench eighteen inches wide, twelve inches deep and from four Fig. 54.— Improvised Kitchen rire-place. to six feet long. At each end a forked stick is placed, of equal heights, with a stout saphng, from which to suspend the kettles, extending from one to the other. This, however, is neither the best nor most economical mode, as it consumes much fuel, wastes much of the heat and causes great inconve- nience to the cook. An improvement can be effected by casing the sides of the trench with brick or stone, adding a chimney at one end and, in place of the forked sticks, using iron uprights and crossbar, to which haK a dozen hooks for the suspension of kettles are attached. In a clay soil a neat, economical and convenient plan consists in dig- ging a hole three feet square and two feet in depth, generally in the slope of a hni. From this a shaft, about one foot square and six feet in length, is run laterally about one foot below the surface of the ground. At the extreme end a shaft is sunk vertically to form a chimney ; and at equal distances three similar holes are pierced of sufficient diameter to prevent the kettles from falling through when placed in position. Kettles placed over these respective holes are made to boil or simmer as desired. Bakery Facilities. — The fact that hard bread is unsuitable for use by troops for any great length of time, together with the fact that at present f la. 55.— Excavated Fire-place in Side of Hill or Bank. there is no article which can replace fresh bread in the dietary, necessitate the establishment of bakeries in the field as weU as garrison. In posts, the management of the flour is taken entirely out of the hands of the com- pany commander and all flour is turned into the post bakery, where the THE RATION. 175 bread used by the men of the entire command is prepared. The apparatus used under such conditions is similar to that employed in small bakeries in civil life and requires no special mention. In the field, however, new- conditions are presented which are peculiar to the military service. For an army operating along a line of raOroad a fbced bakery at the general or secondary base is often constructed and the bread forwarded as soon as baked to troops at the front. This system was employed with great suc- cess in the Army of the Potomac during the Civil War. In camps of any size or permanence iron portable ovens wiU usually be temporarily brought Fie. 56.— Side View of Field Oven, witli Break, Showing Longitudinal Bars Inside. into use, while for marching columns the employment of bakery wagons is practicable. For small commands, not in permanent camps, the baking must be as a rule done by coiapany organkations. Under any conditions, except in fixed bakeries at the base, the preparation of a good quality of bread in the field wOl be a matter of some difficulty, and in very cold weather the production of a fermented bread is almost an impossibility. Portable field ovens, for military use, are usually simple in construc- tion, light in weight, easy of establishment and satisfactory as regards their output. Many varieties were used during the CivO. War. At pres- ent two kinds are issued in our service, these differiag little from each other except in size. The smaller oven, usually issued, is made of sheet steel strengthened with longitudinal bars and transverse ribs. The sheets composing the body are five feet long and thirty inches wide ; so curved that, when their upper edges are connected and lower edges fixed in the ground, they form an arch the span of which is three feet nine inches and the rise one foot four inches. The lower edge of each sheet is bent into a flange, so as to secure a firm rest on the ground. The upper ends of the transverse ribs Fig. 57.— End View of Field Oven. on one of the sheets are formed into hooks and those of the other sheet into eyes, by means of which the parts are secmely united. The front of the oven is closed by a two-handled iron door, which is kept in place by means of hooks and eyes. When the soil is of clay or other favorable quality, the rear end of the oven may be closed by the natural earth; but if it is sandy or loose, a sheet-iron plate is required to close it. No chim- ney is necessary. When set up, the whole, with the exception of the door, is covered with earth to the depth of about eight inches. A larger quantity of earth is liable from its weight to bend the heated iron, and a smaller 176 THEOEY AND PEACTICE OP MILITARY HYGIENE. quantity allows too much heat to escape. An excavation three or four feet in depth is usually made a foot or so from the door, for the convenience of the baker. Two hours are required for heating the oven at first starting, but for each heatiag immediately following one hour will be sufficient. A quantity of wood is placed in the oven at the extreme rear and ignited, the door beiag kept open to afford a draft and a vent for the smoke. Small quantities of wood are added as combustion progresses. In this way the fuel burns more freely, and the oven is heated more quickly, than if aU the fuel necessary for the heatiag is put in at once. As soon as the oven is at a white heat the ashes are raked out, the floor is swept clean and the dough in- troduced in pans. The door is then closed and all interstices are filled with moistened clay or earth. The time required for each baking is about forty- five minutes. As each of the two principal pieces forming an oven weighs only about eighty-five pounds, the whole — consisting of the two sides, the door and end plate — can be easily transported, and can even be carried on a pack animal if necessary. To set up the oven no tools except a pickaxe and a shovel are required ; the sides being merely placed on level ground, fastened together, the rear end closed and the whole covered with earth. Fig. 58.— Portable Oven Used in French Army. (After Laveran.) It can be erected and prepared for use in fifteen minutes, and if kept in constant operation for twenty-four hours can bake sufficient bread for one thousand men. By the use of two of these ovens, therefore, a regiment of a thousand men, if it make a halt of fourteen hours each day, can be sup- plied with fresh bread daily on the line of march. In the French service the portable bake oven used is provided with a chimney. The sections are made with double waUs for better retention of heat, are very light, so as to be transported if necessary by porters, and are capable of being operated independently. A completely equipped field bakery is attached to each army corps, together with a bakery train carry- ing the flour and necessary materials, and, if possible, a two-days' supply of bread. Bakery wagons were tried during the Civil War and have also been much employed in foreign armies. In the French army they have been used successfully in Algeria and Mexico and during the Franco-Prussian War; in the German army they are also used. In construction these wagons are simple. There are two metal ovens connected with a chimney, the latter being lowered during the march. The walls of the ovens are double, or THE EATION. 177 sometimes triple, to prevent loss of heat. The interspace is packed with powdered coral, which is said to so retard the passage of heat that the hand can be held on the outside of the apparatus during the process of baking. These ovens are heated in the usual manner by wood fires kia- dled within them. Special wagons for the transportation of bakery su|p- plies accompany these bakery wagons, and the baking of bread is continued during the march. The capacity of one of these bakery wagons is said to be two hundred rations of bread per hour. The recent model used in the German army is ten feet long, having a fire box for -wood fire below and an oven above. The capacity of this oven is eighty loaves every one and one- half hours. The wagon has the advantage of the older models in being lighter, even if its yield is not as great. Bread may be excellently baked in the Buzzacott range, although the size of the oven renders it scarcely sufficient for more than the needs of a single company. It is much superior to the Dutch oven, so often used. The latter consists merely in a heavy flat iron pot, with short legs and fitted with a flanged top. It is heated by coals beneath and above. Sim- FIQ. 69. — Bakery Wagon, as Used in tlie French and German Armies. Uar to this method is the preparation of bread in mess pans. Of these, the rim of one is cut down so as to leave a ragged border. This pan is then filled two-thirds with dough and the perfect pan inverted over it. Both are then placed in a hole about eighteen inches deep, in which a fire has burned for several hours and from which nearly all the embers have been removed. The whole is then covered with hot ashes and allowed to remain several hours. A frying-pan may also be eiiiployed in the absence of better utensil. It is greased and heated; the dough is then put in, rolledjto about one-half an inch in thickness and the whole set on the fire. The pan is shaken to prevent sticking. When the lower crust is formed the bread is removed, set on edge close to the fire and turned occasionally. Woodhull states that by this method one man with six pans can bake twenty-five pounds of bread in less than an hour. In the absence of special apparatus for the purpose, field ovens may be improvised by excavation of the earth, or from any material available, as sod, wood or brush. The dimensions of such an oven should ordinarily not exceed 150 to 200 rations, unless the arch be of brick or stone. The ration loaf should occupy from 25 to 31 inches of floor space, preferably the latter. For 150 loaves averaging 30 square inches each the dimensions of the hearth should be 31.25 square feet. Ovens made of earth, mud, sod and frames of twigs should preferably contain not more than 100 rations. 12 178 THEORY AND PEACTICE OF MILITARY HYGIENE. The best oven is made ia a steep bank, preferably 4 to 6 feet high. Two men with a spade and a long-handled shovel can build it, in light soil, in three-quarters of an hour. If such tools are not available, it may be constructed with trowel bayonets, entrenching tools or even with knives. To build the oven, the bank is dug down to a vertical face and a hole FIO. ).— Vertical Section ol Oren Excavated Bank. Fig. 61.— Ground Plan of Bank Oven. excavated at the base from 4 to 5 feet horizontally, care being taken to keep the entrance as small as possible ; the sides of the excavation are hollowed and the roof is arched until the floor is about 2 feet 6 inches in its widest part and the roof 16 inches high in the centre. The back end is then tapped for the flue. A hole from 4 to 6 inches in diameter will furnish a good draft, and a piece of tent stovepipe may be utilized for this purpose. It will be advantageous, before using, to wet the whole interior surface of the oven and smooth it over neatly, drying it out and hardening it witii a small fire. The time required for drying out will depend upon the charac- ter of the soil; if ordinarily dry, a fire kept up for an hour wOl suffice. Such an oven has a capacity of about forty rations and will bake good bread in about forty minutes. "With proper care it will last several weeks. Bake-pans may be used in baking, if they can be obtained ; if not, the bare floor, after the ashes are removed, may be used to bake on. After the introduction of the dough, the flue and door should be closed, which may he done with logs of wood, pieces of hard-bread boxes plastered with mud, flat stones, a wet grain sack or piece of canvas. After the oven has been Fig. 62.— Improvised Oven on Flat Ground. Upper portion shows longitudinal section; shoves plan, with ditch. lower portion heated, the degree of heat may be regulated by means of the door and flue, opening or closing them as may be necessary. On level ground an oven is built by digging a hole four feet long, eighteen inches wide and eighteen inches deep. Without enlarging the top, the sides are hollowed from above downward until the floor is about thirty inches wide. At about a foot from one end a trench of suitable dimensions is dug to enable a man to attend to the oven. The partition between the oven and THE RATION. 179 trench is then dug through to form the door. At the back end of the oven a small hole, slanting downward, is dug for the flue. The top of the oven is then closed in with green poles. The interspaces are filled with grass or weeds. The whole is plastered over with mud, after which a sec- ond layer of poles is added and another layer of mud. The oven and trench are then ditched to keep out storm water. Such an oven may be built by two men in one and a half hours. It is much inferior to the bank oven, but has the advantage of being easily constructed and available for imme- diate use. Where a camp is to remain a number of days, a bank oven may be made by digging a pit about five feet deep and then excavating its wall in the manner previously described. Ovens may be made on the surface of the ground of mud, clay or mortar. Wliere mud is used, the admixture of chopped hay will give it strength. To build such an oven a rounded heap of dry earth or sand, about five feet long, thirty inches wide and twenty inches high, should be raised. This is the mould on which the oven is to be formed. Sand is more suitable for the mould than earth, as being more readily removed. Wniow twigs bent over and closely wattled together, or a flour barrel laid flat and covered completely with earth, will likewise suffice to give form to the mould. A stiff mud or mortar is mixed and plastered over the mould five or six inches thick, commencing at the base. One or two days are allowed for it to dry and harden, plastering up all cracks which may ap- pear. When nearly dry, the door at one end and the flue at the top of the other end are cut out. A small mud chimney raised over the flue will greatly improve the draft. The loose earth or sand is then carefully with- drawn from the interior. If a barrel has been used for the mould it may be burned out without damaging the oven. Two men can build this oven in three hours, but it will generally not be fit for use for two days. It will last several weeks and will prove very satisfactory. This oven may also be built dome-shaped, like the household ovens used by the Mexicans. This kind of an arch would be stronger than the semi-cylindrical form, but with the same quantity of material used would not have as great a baking capacity. The clay oven is peculiarly adapted for use when on swampy ground. Under such circumstances it may be constructed upon a platform of stones or logs covered with clay. Dough is kneaded in the field by hand, the operation requiring about forty-five minutes. If pressed for time, it may simply be kneaded on a rubber blanket spread on the ground. A kneading-trough may be readily improvised by digging two paralleL trenches a foot apart, of unequal sizes and depth. The smaller should be lined with plank and serves as a knead- ing-trench to the bakers, who descend into the larger excavation. To facilitate the rising of bread in the open air, an excavation, of con- venient length and width and having a depth of about eighteen inches, is made. This is heated by a small fire, after which the bread is placed in the excavation on brush- wood and the whole covered with branches, plank, hay or grass. With respect to the amount of fuel required in the preparation of the ration, Parkes regards one-half pound per man as sufficient, using a cook- ing apparatus of good type. In the field, in our service, it is customary to rely chiefly upon the vicinity of the halting-place to supply the neces- 180 THEOKY AND PRACTICE OF MILITARY HYGIENE. sary amount of fuel. Where its scarcity is apprehended, a small amount may be carried in the wagons. In the French army, often manoeuveririg in districts in which fuel is scarce, each soldier is frequently required to carry a small piece of wood, in addition to his equipment, for use when camp is established. Meals. — In garrison, breakfast wiU. ordiuarily be about 6:30 A.M., dinner at noon and supper about 5 p.m. The latter meal might be delayed until 6 o'clock, but the soldier himseK usually prefers to have a long evening to devote to his own purposes. Breakfast, in opposition to the views prevailing in foreign services, should be substantial. The last meal has been taken more than twelve hours previously, the stomach is empty, the digestion active and the work of the day is to follow. Under these circumstances the European practice of allowing the soldier merely a bit of bread and cup of tea or coffee appears quite indefensible, at least for this climate. Dinner should be the principal meal of the day, and, like break- fast, should include meat. Supper should be comparatively light. Many men, while in garrison, make a practice of taking a slight lunch at the post exchange before going to bed. It is probable that a small allowance of bread, with coffee or soup, might be issued with advantage from the kitch- en about 9 P.M. to such as choose to ask for it. This would be of special value in a cold climate, particularly to members of the guard. On the march but two meals can be prepared. Breakfast is naturally early. Under favorable circumstances and in commands of moderate size a small limch may be supplied, to be eaten while en route. Preparations for din- ner should be at once begun when the camping-ground is reached ; and this, the heaviest meal of the day, should be ready two or three hours be- fore sunset. In the uncertainties of field service a delayed meal may be a lost one, and a salutary maxim for troops in the presence of the enemy is to eat whenever and as often as they can. Before going into action troops should be given a hearty meal, since they are thus enabled better to endure the strain of battle or pursuit. Service of Ration. — The service of food is a matter which in our army has been given the attention it deserves. Airy and cheerful mess- rooms are provided in aU barracks, and these are fully equipped with an abundance of furniture, crockery, glass and table ware — luxuries which are not even considered as attainable in most foreign armies. Abroad, the soldier eats his food at any convenient place in or around the barracks, using his own cooking utensils, as carried in the field, for that purpose. In the Russian army, food is issued in large mess-pans, out of which sis or eight men eat in common. The same system is in vogue in the French army ; and Laveran mentions the great frequency with which medical offi- cers in that service have been called upon to remove fragments of bone from the throats of soldiers, these liaving been inadvertently swallowed by the men in their eagerness to secure a fuU share of food. It is obvious that such a method of messing is highly undesirable from every standpoint, and certainly would not be tolerated in this country. Even in the field, where the camp is more than ephemeral, efforts should be made by company officers to have the men eat at a common place, to prevent contamination of the tents or theix Adcinity with the dSbris of meals. Ordinarily a tent-fly is soon spread for the protection of THE EATION. 181 tlie cook, and additional flies or a brush shelter subsequently erected for a diaing-room; the men generally managing to erect rude tables and benches of rough lumber, logs or poles. In barracks, troops usually mess as company organizations, with indi- vidual kitchens and mess-rooms. These are cared for, and the messiug crockery and utensils washed, by men specially detailed for that piirpose and held responsible for the maiatenabce of cleanliness. Usually the men employed in the diuing-room and as assistants to the cook are detailed by roster, thus insuriug a fair knowledge of the service of food and the man- agement and preparation of the ration throughout the command. Bread is usually placed on the tables on platters, but meat, vegetables and coffee are served out individually before the meal is announced. This practice has several disadvantages. The portions of food are frequently cold by the time the men are seated, and hence are less palatable. Further, under this system each man usually receives at once a. portion which is supposed to constitute a full meal. If the portions issued were always small the wastage would be less and the untouched remainder could be served over again. In cold weather the crockery should be warmed and no food served before the men are seated. This entails additional work on the waiters, but the extra labor is well repaid by greater contentment among the men. General Messes. — The plan of bringing aU the troops of a garrison into a general mess, for their subsistence, has been tested at a number of the larger posts in this country. When properly administered there can be no doubt that the general mess system, other things being equal, is more economical in the use of fuel, labor and the ration and offers greater vari- ety in the matter of diet. Skilled cooks, however, are necessary to super- vise the running of large general messes, and with enlisted men as cooks the troops will probably fare better when subsisted in company messes. It is much easier to find in a company a man who can cook for a small number of men than in a garrison one who has the ability to administer to best advantage the kitchen of a general mess. Where the general mess system is in vogue the barracks are free from the odors and annoyances which the presence of company kitchens entails, while the concentration for subsistence greatly lightens the labors of the sanitary of&cer as regards the maintenance of cleanliness, attention to proper sanitary detail, inspec- tion of food and its proper preparation. On the other hand, it must not be forgotten that theoretically the normal existence of the soldier is in the field, where he may frequently be called upon to prepare his ration for himself. It is particularly in this respect that the general mess system is weak, for the cooking in such an establishment is carried out on so large a scale, and the apparatus provided is so totally at variance with the mea- gre cooking outfits available for the field mess during campaign, that the average soldier cook, who may have served a detail as an underling in such a general mess, is rarely competent at once to undertake the responsibilities incident to cooking for a company in the field. In the general mess, also, the kitchen staff is largely of a permanent character and comparatively few men are thus enabled to acquire a practical knowledge of cookery. It may therefore be concluded that, while possessing many undeniable advan- tages for troops in garrison, the general mess is, on the whole, inferior to the usual plan of preparing the food for each organization in its own kitchen. 182 THEORY AND PEACTICE OF MILITAEY HYGIENE. In general, kitchens and mess-rooms will be better conducted if they are placed under the immediate charge of non-commissioned officers, who should be held responsible for their condition and for the proper use of the ration. No one should be allowed to visit or remain in the kitchen except those who go there on duty or are employed therein. Foraging, — To rely on the coimtry for means of subsistence, especially in view of the vast numbers of men which are massed together in modern wars, is ordiuarily extremely hazardous. A retreating enemy wiU endeavor to destroy all stores likely to be of value, while the inhabitants along the line of march, whether friendly or hostile, have usually removed aH avail- able food to secret hoards for their own use. Under such conditions the army operating ia a friendly territory is at a disadvantage, since it neces- sarily shows far greater consideration as regards the property of the civil- ian population than would a victorious enemy. This fact was strongly exemplified ia France in 1870-71, when the French troops, operating on their own soU, were unable to obtain in the way of food a fraction of what the iavadiag Germans subsequently wrung from an unwilling and hostile population. Foraging will ■ often do much toward eking out deficient sup- plies, and, where shortage is imminent or transportation is scanty, it should be authorized. Lootuig, however, should not be permitted ; the foraging should be done only by parties detailed for that purpose under responsible officers, and everything taken should be paid for with vouchers. Billeting. — In this country the bOleting of troops on a civilian popu- lation, for purposes of subsistence, is never required. In foreign armies, however, this procedure is common. French regulations provide, where troops are to subsist on the country, that soldiers may be told off for sub- sistence by the inhabitants of a town or region at the rate of four to six for each fireplace. In case of great necessity this may be increased to four to six for each inhabitant. In the German army similar regulations pre- vail. In the Austrian army the number of soldiers billeted may be equal to the civil population of the place. Troops billeted in this way are en- titled to the usual fare of the country. Usually soldiers are not billeted on a civil population for more than three or four days. Requisitions as a Means of Supply. — The rapidity of movements in modern warfare wiU reduce the value of magazine rations as a source of supply, so that the system of requisitioning when in occupation of an ene- my's country will be not infrequently employed. According to Eiordan the most densely populated place can fiirnish food and quarters for as many troops as there are inhabitants, and for a less number of troops for several days. Hazenkampf arrives at the following conclusions: (1) If the popu- lation of a given point or locality be equal to the number of troops, it can supply them for a period of four, but not more than six, days. (2) If the number of troops be half the number of the population, they can be main- tained at the expense of the latter for one or two weeks. An army of sixty thousand men can be easily supplied from the means of a country which has one hrmdred and fifty inhabitants per square mile, but only while on the march. It must not halt at one place in a concentrated position. The foUowing rule is given for demanding supplies on requisition : One ration daily for every three inhabitants of a weU- cultivated district, and one for every six inhabitants in mountainous or poorly cultivated countries. THE EATION. 183 In cases in which, an army operates in countries either devastated, un- cultivated, mountainous or thialy populated, or has to fight for several days consecutively on the same ground, or has to meet the resistance or cunniug of the inhabitants, it is plainly impossible for it to subsist on the resources of the country. The Germans, who made such a large use of requisitions during the Franco-Prussian war, do not appear to have had any iixed rule upon which to base their demands. Forse says : " The aim of the German officers was evidently to exhaust all the occupied towns and to make it absolutely impossible for them to assist finally in contributing toward the expenses of the war." The system of requisitions has been much used abroad, not only during the Franco-Prussian war but during the Napoleonic wars and the Kusso-Turkish war of 1878. The British have frequently employed this system of supply in their expeditions, notably in the Afghan- istan campaign. II. SUBSISTENCE AND MESSING IN FOREIGN ARMIES. The ration of the British soldier at home stations, supplied gratuitously by the Government, consists merely of 12 ounces of meat with bone and 1 pound of bread daily. In addition, a grocery ration is provided by a stoppage from the soldier's pay, usually about 3-J pence daily per man. This latter sum is at the disposal of the various companies in a regiment, and is usually expended on the purchase of extra bread, tea, sugar, pota- toes, vegetables and other articles. Under canvas, 1 pound of bread and 1 pound of fresh meat or 12 ounces of preserved meat are allowed. In billets on the march, 20 ounces of bread, 1 pound of meat and 1 poimd of potatoes or other vegetables are authorized, together with vinegar, salt and pepper. Duriag campaign, when required by the senior medical offi- cer, a daily ration of half a gill of rum is issued and a small deduction made therefor from the soldier's pay. At stations abroad, the ration is ordiuarily the same as the issue under canvas at the home stations. In case of active operations in the field a special scale is fixed according to climate and circumstances. For this the following is accepted as a guide to be used as far as possible : One poimd fresh, salt or preserved meat ; 1 J pounds brpad or 1 pound biscuit or 1 pound flour; -J oimce tea; -^ ounce coffee ; 2 ounces sugar ; ^ oimoe salt ; -gig- ounce pepper ; ^ pound fresh vegetables, when procurable, or 1 ounce compressed vegetables. To this is added ^ gUl of lime juice and 1 ounce sugar on days when fresh vege- tables are not issued. During campaign, if the supply of cattle is abim- dant, the allowance of fresh meat may be increased to 1^ poxmds. Where troops are under canvas the money value of ^ pound of fresh meat may be expended in the purchase of cheese. Notter and Firth give the free ration and grocery ration as being ordinarily made up as follows : Articles. Quantity in ounces. Meat 12 Bread 24 Potatoes 16 ' Other vegetables 8 Milk 3.25 Articles. Quantity in ounces. Sugar 1.33 Salt 25 Coffee 33 Tea 16 The lack of fat, vinegar and pepper ia this dietary is noticeable. 184 THEOEY AND PEACTICE •OP MILITAEY HYGIENE. The number of men in a mess in the infantry is usually the number that each barrack-room contains. Special dining-halls are provided in but few barracks and the men eat in their squad-rooms, storing their bread and the articles of food purchased by themselves on their shelves or in their lockers. But two hot meals a day are provided, supper being merely sweetened tea with such bread or other food as may be still uneaten by the soldiers. Few men appear to take advantage of this bread and tea issue, and nearly all purchase their suppers at the canteen. The sergeants have a separate mess. Cooking is done in a regimental cook house ; each company cook, usually trained at Aldershot, preparing the meals for his own organization under the direction of the sergeant cook. Cooking is generally done by baking or stewing. The British system of cooking, messing and service of food appears to be ia all respects far inferior to our own and leaves much to be desired. The food allowance in the German army is based on the recognized general principle that greater physical exertion necessitates a more gener- ous supply of nutriment. In time of peace two rations are allowed, one being used in garrison and the other in camp or for field manoeuvers. Their constituents, according to Notter and Firth, are as follows : Articles. Bread Meat, fresh Or Bacon Smoked meat (war only) Eioe Or Oatmeal Peas or beans Potatoes Salt Eoasted coffee Brandy Or Beer Wine Butter , Tobacco Field ration, ounces. 35.30 17.65 6.00 8.82 6.00 6.00 13.00 71.00 .88 1.41 3.53 35.30 17.65 1.76 1.41 The quantity of vegetable food given in these rations is so great as to arouse suspicion as to the correctness of the figures quoted. The amount of meat also is considerably greater than the figures obtained by the com- mission lately investigating the dietary of the British soldier, which placed the German meat ration in war at but 8.81 ounces. Of the above articles the Government issues free, in time of peace, the bread ration ; the other articles are provided by a stoppage from the sol- dier's pay amountiag to about three and a half cents daily; and, as this is insufficient, the Government furnishes a supplementary subsistence allow- ance, determined for each garrison from the local price of foods during the preceding quarter. The bread, made of a mixture of wheat and rye flour, is furnished in kind and can be commuted only in exceptional cases. The reason for this is stated to be that jthe men should be well nourished and not be tempted to eat more palatable but less nutritious foods. This bread is either baked in the military bake-houses or may be directly contracted for from civilian bakers. The method of usiag the ration varies with the THE EATION. 185 garrison. Cooking is done with steam kettles, and the meat ration is roasted only exceptionally. Usually it is prepared ia the form of a thick soup or stew. Two fuU meals a day are ordinarily issued, the first repast consifctiag usually of coffee alone. In some instances bread is used three times daily — ^twenty per cent, for breakfast, fifty per cent, for dinner and thirty per cent, for supper. Kitchens are provided in barracks, as are also mess-rooms. The latter are used for purposes of assembly, recreation or instruction other than at meal-times. Usually a battalion messes together. The non-commissioned ofiicers mess separately. The following is the daily ration during war : Articles. Quantity in grams. Bread 750 Or Biscuit 500 Fresh meat 375 Or Smoked meat 350 Preserved meat 300 Bacon 170 Articles. Quantity in grams. Eice, millet or oatmeal .... 125 Or Dry vegetables 350 Potatoes 1,500 Salt 35 Coffee 35 In the enemy's country this ration may be increased by an issue of spirits. Under certain conditions, as when troops are billeted on the march, the rations are commuted. Eeimbursement in these instances is made according to tariffs based on local prices for food. Under such conditions troops are, by regulation, entitled to the usual fare of the country. In the French service, a small amount of meat is furnished at a reduced rate by the Government, and the state also supplier bread and fuel gratis ; the white bread for soup and other articles, except a small amount of coffee and sugar, being purchased from the company funds provided by the Gov- ernment. In time of peace the meat allowance is 300 gm. ; the allowance of "munition " bread is 750 gm., or of biscuit 550 gm. Usually the pur- chases from the company funds include 250 gm. of soup bread and 100 gm. each of fresh and dried vegetables per man. Laveran states that in garrison the food actually eaten by the French soldier yields about 124 gm. of protein and 760 gm. of carbohydrates. The amount of fat is too small, amounting to only about 60 gm. daily. These quantities would possess a fuel value of 4,182 Calories. Ordinarily, beef is issued four days weekly, and mutton twice. Codfish is eaten on Fridays. In the field a larger ration is issued, this varying considerably with the particular service on which troops are employed. The " strong " ration for campaign contains the following articles : Articles. Quantity in grams. Bread 750 Or Biscuit 600 Bread, dried (pain biscuite) 700 Rice 100 Or Dry vegetables 100 Salt 30 Sugar 31 Coffee, roasted 34 Articles. Quantity in grams. Fresh meat 500 Or Bacon 300 Preserved meat 350 Lard 30 Condensed soups 35 Wine (occasional) 350 c.c. Brandy (occasional) 63 c.c. As in the British service, meals are ordinarily eaten in the squad- rooms, no mess-halls being provided except in a very few of the latest type of barracks. In these barracks there is one kitchen to each two squadrons, 186 THEORY AND PEACTICE OE MILITAEY HYGIENE. but each, squadron has a separate mess-room. Two meals a day, in addi- tion to coffee ia the morniag, are prepared. Mess-gardens are encouraged wherever possible. In each company or fraction of a company a soldier is designated by turn to prepare and cook the food, usually for the peritod of three months. Each cook has an assistant who is relieved weekly. The sergeants do not mess with the men but eat at the canteen, the cantiniferes being obliged by the letter of their appointment to run a sergeants' mess at a rate fixed by the commanding officer. In the Austro-Hungarian army the ration in time of peace consists of an allowance of black bread, amounting to 875 gm., issued in kind, and a money allowance, for breakfast and dinner. The breakfast portion con- sists of bread, soup, tea, coffee, or brandy; the dinner portion of 190 gm. of beef and 140 gm. of desiccated vegetables, or a corresponding quantity of fresh vegetables. This ration, according to Laveran, yields 17 gm. of nitrogen. On the march, troops receive cooked subsistence in kind, con- sisting of 280 gm. of meat and one other article of food. In time of war the amount and constituents of the ration vary according to circum- stances. The fuU war ration is issued during the concentration of the army after mobilization, the "nachschub " ration during active operations, and the reserve ration in case of emergency. The composition of these rations is as follows : Articles. la § . SSg IsS gsa. S5 .a N ^ se Substitutes in lieu of articles of the full ration, grams. Bread . Or hard bread . Fresh meat Meat conserves Vegetables (rice, barley, grits, or other dry vegetables) Sausage Salt Pepper or paprika. . . . Fat (lard, butter, etc. ) Soup conserves Coffee . Sugar . . Brandy . Tobacco Cigars (number).. 700 500 400 140 30 .05 20 36 25 25 9c.l. 35.23 6 700 500 400 140 "30 .05 30 36 25 25 17.8 250 290 "25 86 25 25 200 25 25 25 Meat, 400 ; vegetables, 400 ; flour, 400; potatoes, 2,000. Pork, mutton, veal, 500; sausage, 200; cheese, 250 ; tinned meat, •200. Meat, 100; or flour, 140; sauer- kraut, 300; potatoes, 1,000. Flour or meal, 26; lard, 40, and caraway, 1.5. Tea, 6; sugar, 25; rum, 4 c.l. ; or cocoa, 25; sugar, 30. Wine, 40 c.l. ; or beer, 75 c.l. ; or rum or brandy, 6 c.l. The commanders of armies, of detached corps or divisions, or even of smaller forces in the field, are authorized to change and supplement the ration, or even double it under certain circumstances. Eegimental com- manders are required to supplement the " nachschub " ration with fi-esh vegetables, etc., if possible, when the troops are in bivouac or cantonments. THE RATION. 187 For this purpose a special money alllowance is granted or each day that the " nachschuh " ration is issued. This extra allowance is not granted in an enemy's coimtry, the supplement to the ration being obtained in this case by requisition. The allowance of fresh meat is increased by 200 gm. on days when the reserve ration is issued, when beef cattle can be obtained in the enemy's country. In the Eussian army the garrison ration is composed as follows : Articles. Grams. Flour 820 Or Bread 1,230 Biscuit 820 Articles. Grains. Groats 136 Fresh meat 205 Vegetables, variable quantity. When circumstances warrant the issue, the allowance of meat is increased to one pound per day. In addition to the food allowances there is also a money allowance for the purchase of vegetables and condiments, varying in value with the nature of the duty being performed by troops. Any of the above articles may be replaced by others according to the following scale: One-quarter pound of barley or oat groats equals .9 poimd of peas or beans, 1.7 pounds potatoes, 2.2 pounds turnips or carrots, 3.2 pounds cabbage. In time of great hardship, according to Viry, the amount of flour may be increased to 930 gm. This quantity is much in excess of the needs of the soldier and the portion unused is either sold or used in the manufacture of the Eussian beer, or "kvass." Oatmeal is usually prepared with fat, and is much liked. Kitchen gardens are usually cultivated; potatoes are little used, reliance being chiefly had on cabbage and legumi- nous vegetables. Fast-days are rigorously observed to the number of one hundred and fifty annually, and on these days fish soup, purchased from the company funds, is issued. There are but two heavy meals a day. Although tea is a national beverage in Eussia it does not enter into the official ration but is purchased by the soldiers themselves. In time of war the ration is greatly increased according to circumstances. In the expedition against the Turcomans of Khiva the ration was composed as follows : Articles. Grams. Meat (on the hoof) 820 Biscuit 820 Groats 205 Flour 17 Articles. Grams. Fat (lard, tallow or butter). .* 21 Dried peas 140 Salt 55 Also tea, sugar, and brandy. Notter and Firth give the larger Eussian war ration as ordinarily con- taining, in ounces — ■ Articles. Ounces. Rye bread 36.15 Meat 21.67 Articles. Ounces. Groats 4.80 Butter or tallow 2.73 This is said to have the following nutritive value : Protein, grams. Fat, grams. Carbotiydrates, grams. Fuel value. Calories. 164.14 117.08 530.40 3,894 188 THEOEY AND PEACTICE OF MILITAKY HYGIENE. The peace ration of the Italian soldier is as follows : Articles. Ounces. Bread 33.40 Meat 7.06-10.59 Lard or bacon .53 Rice 5.30 Articles. Ounces. Salt 58 Sugar 71 Coffee, roasted 53 Wine 8.83 Eeduced to its proximate principles, this diet contains 3.99 ounces of protein, 1.34 ounces of fat and 21.64 ounces of carbohydrates. The camp- ing or marching rations are similar to the above, except that the allowance of meat is somewhat greater. The food for the troops is prepared in com- mon; the sergeants have a separate mess. Ordinarily two meals are served daily, but when the exigencies of the service require it the food may be issued but once daily. Bread is obtained both from the military bake-houses and by contract. For field service a considerable number of rations of varying composition are authorized. The field ration lq the Swiss army consists of the following articles : Grams. Bread 750 Fresh meat : 375 Vegetables (rice, pulse, etc.) . . 150 Grams. Salt 30 Coffee 15 Sugar 20 Eiscuit may be substituted for bread ; and instead of fresh meat there may be 'issued salt or smoked meat or bacon, canned meats, or cheese, in the following proportion : 500 gm. of biscuit for 750 gm. of bread; 275 gm. of salt meat or 250 gm. of smoked, dried or canned meat or bacon, or 250 gm. of cheese, for 375 gm. of fresh meat. When troops are exposed to very severe work or cold weather, extra subsistence may be issued, amount- ing in the meat ration to an increase to 500 gm., or to an addition of 65 to 125 gm. of cheese, and 3 to 5 deciliters of wine or 6 to 10 centiliters of brandy. In the Spanish army the ration received by the soldiers consists merely of 650 gm. of bread — about 23 ounces. During peace, the soldier's pay is drawn upon to the extent of about 30 centimos daily tO furnish the remain- der of his subsistence, the exact amount varying ia the discretion of the colonel or chief of battaKon. Coffee with sugar is served at about 7 a.m., while the heavy meals of the day come at about 11 a.m. and 5 p.m. The food of the soldier naturally varies ia character and quality with the region and the preferences of the commanding officer. No accurate figures as to the actual nutritive composition of the food ordinarily eaten by the Span- ish soldier appears to have been made. As a rule, the various parts of the repast are cooked and served together as a mixed dish. Mess-rooms and tables are provided only for non-commissioned officers ; the privates eat in any convenient point of the barracks or barrack yard. Each company usually has a different m&u, and it is a common practice, in large com- mands, for soldiers from different companies to come together and share their food with each other to secure the desired variety. For field-service, no less than ten different rations, entirely dissimilar in character, are authorized. In the army of Holland the ration consists of two parts. One, the bread, is furnished gratuitously by the Government; it amounts to about twenty-two ounces. The second portion, which includes meat and groce- THE EATION. 189 ries, comes out of the soldier's pay and is purchased by company officers. Great liberty being thus given, the Government has laid down certain regulations fixing the minimum quantity of daily food which must be fur- nished to the soldier. These scales vary with the season. In time of war the ration is as f oUows : Or Groats 0.20 kgm. Rice or meal 25 " CofEee 02 Sugar 01 " Salt 03 Pepper 0005 " Vinegar 04 liter. Gin (under special cir- cumstances) 5 " Three meals are issued daily, the breakfast usually consisting of a thick rich soup; though sometimes of coffee, bread, butter and cheese. The other meals are heavier. The sergeants mess together and contribute a considerable proportion of their pay for their subsistence. The rations of the Swedish soldier vary largely in composition. Ac- cording to Viry, the average nutritive composition has been estimated to be as follows: Protein, 185 gm. ; fat, 108 gm. ; carbohydrates, 671 gm. The ration of the Turkish soldier is said by Viry to be composed as follows : Meat . .4 Or Pork . .25 " Mutton Smoked or salt pork . . Pickled fish . .30 " . .20 " . .50 " Potatoes ; . . Or Green peas Beans . 2.25 liters. . .40 " . .50 " Grams. Bread 850 Mutton 250 Eice 85 Salt . . . , Onions , Grains. . 20 . 20 The ration of the Belgian soldier consists of : Ounces. Munition bread 26.47 White bread 70 Meat 8.82 Potatoes : 85.8 Ounces. Butter 0.7 Lard 35 Salt 1.00 CofEee 9 This ration contains about 17 gm. of nitrogen; the fats amounting to about 40 gm. The sergeants mess together ; receiving three meals a day, at two of which at least one dish of meat must be served. It is customary for the sergeants to contribute from their own resources to supplement the food provided by the Government. The men receive three meals daily. Of these the first consists of bread and coffee ; the second of soup, meat and vegetables ; and the third usually of bread and vegetables. Cooking is done by men detailed for the purpose. In the Japanese army, in time of peace, each soldier receives daily about thirty-sis ounces of rice, and a money allowance of six sen for the purchase of beef, chicken, pork or fish, vegetables, pea flour, tea and pep- per. The ration during the late Chino-Japanese war consisted of : Ounces: Rice 36 Chicken, beef, pork or flsh 5 Or Preserved meat 2^ Dried meat 8f Vegetables, fresh 5 Or Dried vegetables li Ounces. Or Spiced vegetables 1|- Preserved plums 1-J Salt i Soy, miso and tea in varying quantities. 190 THEORY AND PEACTICE OF MILITARY HYGIENE. In hot weather, during the war with China, hard flour biscuit was sub- stituted for rice, as the latter, when boiled, was apt to decompose. The quantity of biscuit issued is not stated. The cooking in the field is sim- ple ; the rice is boHed in large boilers, each man adding to his portion his can of preserved meat, vegetables or spice. This ration is markedly de- ficient in fat, a fact which was recognized by Ogata in the ration proposed by him, and which was so successful in reducing beri-beri among the Japanese naval forces. The Japanese ration is said closely to resemble that of the French native Annamite troops. The ration issued to the military forces of the Argentine Eepublic is of especial interest through its marked contrast to that issued in other nations, especially Japan. This ration, according to Gache, is composed of 1,370 gm. (3 pounds) of fresh meat; biscuit, 250 gm. ; rice, 56 gm. ; mat^, 77 gm. ; sugar, 100 gm. ; coffee, 36 gm. This remarkable dilfer- ence in respect to meat components is to be explained by local customs of diet and the fact that meat, costly in Japan and Europe, is extremely cheap and abundant in Argentina. In the army of Chih the ration is composed of the following articles : Grams. Meat , 460 Rice lao Flour 340 Beans 250 Onions 50 Fats 40 Grams. Sugar .• 45 Potatoes 100 Coffee 15 Salt 25 Pepper 5 Any attempt at a comparison of the rations of foreign armies, either among themselves or with our own, would seem to be productive only of misleading results. Not only must quantity be taken into consideration, but also quality and the method of preparation. To these, the varying factors of custom, race and climate must be added. On the whole, the rations of foreign armies would seem to contain altogether too small a pro- portion of fats. As far as the garrison and peace ration provided in most armies is concerned, it usually is quite insufficient — even in some cases approaching mere subsistence diet — and the soldier is not only tacitly but officially expected to supplement it from his own resources. In most ser- vices a large share of the pay nominally allowed, as in the Spanish army, never reaches the soldier, but is expended for his subsistence by a superior officer; in other services a smaller stoppage is made against the soldier's pay, but he is practically required — as in the British army — ^to purchase one meal daily at the canteen or other outside source. In stiU other ser- vices, as in the German army, the food allowed by the state and the pro- portionally large stoppages from the meagre pay of the soldier are together insufficient for his proper sustenance. Lacking outside means, the soldier must, under the last conditions, either receive food from his friends, sup- plement his pay by performing duties for his wealthier comrades, or prac- tically become an object of charity to the civilian population among whom he is stationed. Such an undesirable condition of affairs cannot of course exist in an army recruited purely by voluntary enlistment, as is our own, and in a country in which both the scale of wages and standard of living are high. To secure recruits by voluntary enlistment the service must be THE RATION. 191 made attractive, and in accomplishing this end an abundance of good food is a potent factor. Hence it is that the United States army is, as far as the garrison ration is concerned, by far the best fed army in the world. For field service it is obvious that the soldier will usually have neither the opportunity nor the wherewithal to add to his diet. All nations recog- nize the paramount value of proper nutrition where hard labor is to be per- formed, and appreciate the false economy of too greatly reducing the sol- dier's diet under such conditions. Hence for field service the rations of foreign armies are greatly increased imtil, as in the case of the Austrian ration, doubled ta time of war, the food allowed the soldier may even be in excess of that supplied in our own service. The statement may there- fore be accepted without qualification that no civilized nation will, at the present day, attempt to maiutaiu an under-fed army ia the field. All fully appreciate that generous subsistence is an element in the absence of which there can be no efficiency, and that parsimony in respect to food will bring its own punishment through defeat. III. the several articles of the ration. Meat and Fish Components. In the United States service meat is supplied in the fresh state as beef or mutton. and in the salted or preserved condition as beef, bacon or pork. It ordinarily rests with the department commander as to how much of each kind of article the soldier shall have, and it is customary to direct that in ten days there shall be seven issues of fresh beef, two of bacon and one of pork. It usually happens, however, that much of the pork and bacon is not drawn, but the money value of the same saved and expended for articles of food of a more desirable nature. Except in the field, when fresh meat cannot be supplied, salted or preserved meats are not employed to any considerable extent. Under the best of circumstances these arti- cles soon become distasteful, and the craving for fresh meat which early ensues is responsible for the foraging expeditions which soldiers in the field, long deprived of fresh supplies, are so prone to undertake. This craving is well understood by the authorities in all armies, and every effort is made to supply the want by providing freshly killed or refriger- ated meat, in garrison or distributed from convenient points in the field, or by purchasing beef cattle to be driven with marching troops and slaugh- tered as required. Under all circumstances fresh meat should be supplied where it can be obtained. Fresh Meat. — In our service it is intended that the soldier shall receive the fuU benefit of the fresh meat ration, and no savings in this respect can be purchased by the Government. The daily allowance of twenty ounces for the United States soldier is ample when the meat is of good quality, and is far more generous than the ordinary fresh meat ration of foreign armies. Its weight, however, is not based upon meat free from bone; and hence a deduction of ten to thirty per cent., according to breed and cut, must be made for bone from the gross allowance. In determina- 192 THEORY AND PEACTICE OF MILITAEY HYGIENE. tions made by the Subsistence Department the average proportion of bone in beef, for the parts of the animal issued, was found to be about lifteen per cent. In mutton the proportion of bone is said to be somewhat higher. The waste due tO' bone is relatively greater in young animals, and in veal it may amount to as much as thirty per cent. As a general rule the pro- portion of bone in fresh beef suitable for issue wOl not exceed twenty per cent. Under the influence of cooking the weight of the meat ration still fur- ther diminishes. When meat is boiled for a long period the loss may amount to as much as thirty-five per cent., while roast meat may lose an even more considerable part of its weight by evaporation and by the melt- ing of its fat; the decrease in weight beyond a certain point being ap- proximately proportionate to the amount of fat present. In the ordinary processes of cooking the following results have been obtained by the Sub- sistence Department : Pour pounds of beef lose rour pounds of mutton lose . . In tolling. 1 pound. 14 ounces. In baking. 1 pound 3 ounces. 1 " 4 " In roasting. 1 pound 5 ounces. 1 " 6 " The flesh of young animals, as veal, loses greatly in weight, forty to sixty per cent., as a result of cooking; and very great loss is also said to occur with the flesh of half-fed cattle. In cutting up the meat there is also a small waste, and it is thus evident that the fresh meat ration of twenty ounces, as delivered from the block, undergoes a diminution of about forty- five per cent, before being served — leaving the soldier only about eleven ounces of cooked flesh as a daily net allowance. Viry states that in the French army the amount of cooked meat available for the soldier wiH not exceed thirty-five to thirty-eight per cent, of the raw weight. He places the ordinary proportion of bone in the beef issued in the French service, known as second quality beef, at twenty-four per cent. It is true that a certain amount of the fat lost by the meat is returned to the soldier in the form of gravy; and the bones, when used in soup, possess a considerable nutritive value, especially when crushed, reckoned at about one-third that of an equal weight of beef in carbon and about one-sixth in nitrogen. The unavoidable loss is, however, considerable, and it may be accepted that the fresh meat ration, as issued from the block, ultimately affords the soldier the nutritive equivalent of not more than thirteen to fifteen ounces of bone-free meat ; its value varying slightly with the economy of the cook and the method of preparation. For the American soldier, accustomed to the use of a considerable quantity of meat in his dietary prior to entering the army, the above amount wiU. not justly be considered as any more than sufficient in quantity, so that it behooves all who are concerned with the soldier's ration to see that he receives the fuU benefit of the excellent qual- ity of meat with which he is supposed to be provided. Meat Contracts. — In this connection it may be emphasized that the present system of awarding meat contracts, covering long periods, to the lowest bidder, is distinctly opposed to the interests of the soldier and favors sharp practice on the part of the contractor. Constant watchful- THE RATION. 193 ness by sanitary officers is necessary to insure that the requirements of the contracts are properly carried out; for where competition is keen and the successful bidder secures his contract at a figure so low as to allow but a very small margin of profit, the temptation is great for unscrupulous deal- ers to supply troops with meat of inferior quaKty. It is undoubtedly the case, in many iustances, that contractors bid so low that, if any unforeseen contingency arises, it is out of the question for them to supply meat of good quality at a profit. The rule of accepting the lowest bid, irrespective of other considerations, may thus frequently deter honest men from under- taking a contract for supply, which, by the stringent working of this rule, naturally falls to the less scrupulous speculator. Without the exercise of great care, beef from old or diseased animals, and from those in poor con- dition from long travel or hardship, wUl be offered for issue ; while con- tractors who have a civil and military clientele are prone to sell the choice cuts to outside customers, furnishing only cuts of inferior quality for the use of troops. The meat supplied is too frequently on the border line be- tween good and bad, and of&cers are imfortunately too prone to pass over minor delinquencies on the part of contractors and fail to hold the latter to the strict letter of their contracts. In foreign armies the necessity of constant inspection of meat is fully appreciated; in the English, French, German and other services the senior medical officer with a regiment is required to inspect and approve all meat intended for issue to troops, and is held responsible for its good quality. Western beef cattle are in poor condition at certain seasons, particu- larly after drought or following a hard winter and late spring. Meat from such animals is naturally tough and lean, and possesses an undue proportion of bone. Where beef contracts are awarded for as long a period as one year, and at a price which prevents the contractor from supplying beef from other than neighboring and often sterile ranges, the quality wiU. be periodically subject to criticism. StaU-fed animals might with advantage be contracted for — at least during certain specified seasons of the year. Where dressed meat is contracted for, it would be much to the advan- tage of troops if the practice of making local contracts could be discontin- ued and dealings be had, wherever possible, direct with large firms of known reliability, operating establishments at centrally located points. At these large establishments competent Government inspectors are always on hand, and would thus pass upon the quality of all meat intended for the military service, its uniformly good character being thus maintained. As far as troops located in the eastern, *middle and southern states are con- cerned, it would seem as if this direct method of supply should in most cases entail little if any additional expense, since the profits of the local dealers, who themselves obtain most of their meat from these central estab- lishments, would thus be largely avoided. While of importance to the wel- fare of the soldier at aU times, it is particularly in time of war that the inspection of meat, either on the hoof or on the block, should be carried out with the greatest care to prevent knavery on the part of contractors. Military Abattoirs. — To avoid the many disadvantages of purchasing dressed meat by contract, government abattoirs have been established in connection with some of the larger military garrisons in France, Germany and England. Where smaller bodies of troops are located near towns, the 13 194 THEOEY AND PRACTICE OF MILITARY HYGIENE. municipal abattoirs are in many instances used by them on certain days of the week. The animals slaughtered are carefully inspected by compe- tent officers both before and after killing, and an excellent quality of meat is thus insured for issue. As the purchasing agents of the Government usually deal directly with the cattle raisers, the profits of the middle-nian are largely avoided, to the benefit of both the stock raiser and the state. This system has not been employed in our service during time of peace ; but in certain instances it might with advantage be adopted. Beef. — In the United States service, mutton is rarely issued and fresh meat is almost invariably supplied in the form of beef. The latter, next to bread, therefore becomes the most important article of the soldier's diet. In its chemical composition, beef varies so greatly with the cut and with the condition of the animal that it is extremely difficult to formulate any averages for the whole. Analyses of some of the more important cuts, however, shown in a subsequent illustration, yield the following figures : Out. Water, per cent. Protein, per cent. Fat, per cent. Fuel value per pound,Ca]ories, Fore and hind quarters, average. Chuck 50.5 54.0 52.9 48.0 62.5 46.9 57.0 14.7 15.8 16.4 13.8 19.2 15.2 , 16.5 15.8 15.5 16.9 24.8 9.2 18.6 8'.4 944 820 Loin 1 020 Eibs 1,305 745 Rump 1,065 660 Shoulder clod Contracts for the army require that fresh beef shall be good in quality and condition, fit for immediate use, and from fore and hind quarter meats proportionally, including aU the best cuts thereof. Beef from bulls, stags, cows, hornless or diseased cattle shall not be delivered. The necks of the cattle slaughtered for beef shall be cut off at the fourth vertebral joint, and the breasts trimmed down; the shanks of fore-quarters shall be cut off four inches above the knee-joint, and of hind-quarters eight inches above the hock-joint. Necks, shanks and kidney tallow shall be excluded from delivery. It has been found by the Commissary Department that in a steer dressed according to contract the fore-quarters weighed 310 pounds 15 ounces, and the hind-quarters 268 pounds 13 ounces — the excess in weight of the fore-quarters being 42 pounds 2 ounces. This proportion has been found to be general; consequently, in receiving fresh beef under contract it should be expected that the proportion of fore-quarters meat to hind-quarters meat would be about as eight is to seven. As to the char- acter of eating beef, cattle may be graded in the following order : Spayed heifer from four to seven years old ; steer or bullock (never worked) from four to six years old; "free-martin," or barren heifer, not over eight years old ; ox from five to eight years old ; heifer from three to four years old ; cow from three to eight years old. Beef Cattle. — The pm^chase of animals on the hoof, for slaughter as food for troops, is a common procedure in foreign armies, many of which, as stated above, maintain military abattoirs, but the practice is comparatively rare in our own service. Under present conditions, within the United States, the supply of dressed beef to troops is usually easy of accomplishment ; but THE EATION. 195 in war the reverse may be the case and the purchase of live cattle may be- come necessary. Before the adoption of modem processes of preservation, troops dm'iiig campaign were obKged to depend on the country for their supply of fresh meat — at best an insufficient and precarious source of sup- ply — or have recourse to herds of beef cattle provided by the commissariat and driven with the army. Where troops are operating far from railroads, or at a long distance from the base of supply, these methods may still be necessary; but they present many obvious disadvantages, as experienced in our army duriug the Civil War. Where a subsistence herd accompanies troops the meat soon becomes poor ia quality, tough and presentiug an imdue proportion of bone from insufficient grazing and much driving. If marching is constant and movements are rapid, it may frequently happen that the herd is left behind and not available when hard service renders the issue of good meat most to be desired. The subsistence herd has also not infrequently become infected with contagious disease, restdting in the death of many diseased animals and the necessary slaughter of others. During the Franco-Prussian war the beef cattle of the invading Germans were largely diseased, and were credited with causing outbreaks of sickness in the population of the regions through which they passed. Wherever beef herds are maintained they should be under careful and constant in- spection, and any sick or ailing animals at once separated from the others. All meat-producing animals should be examined while living and after they are killed. Both inspections are made because there are some condi- tions that cannot well be detected after the animal is slaughtered, but which often have an important effect on the quality of the meat, as fever, fatigue, exhaustion, starvation and excitement. When animals are pur- chased in any large quantity the services of a veterinarian should be avail- able, but in his absence the medical officer should be able intelligently to carry out the necessary inspection. This duty is by no means difficult of performance, since the sick and unsound animals are readily eliminated and sex, age, and condition are at once determined — ^these being the most important factors in estimating the quality of the meat. Animals should be inspected twenty-four hours before being killed. Such as have been accepted by the inspector should be at once branded or otherwise properly marked to prevent possible substitution and fraud. Weight. — Where live beeves are purchased it is specified in regulations for the Commissary Department that animals weighing less than 1,000 pounds or more than 1,400 pounds must not be accepted except in case of necessity, when the purchase of those weighing less than 1,000 pounds is permitted. Ordinarily a net weight of 600 poimds is expected. It is required that aU animals offered for sale shall be kept without food or water for the twelve hours immediately before weighing. The present method used in our service for estimating the net weight of cattle on the hoof is officially laid down as follows : Gross weight. Estimated net weight. 800 pounds and less 40 per cent, of gross weight. Over 800 pounds and less than 1,300 pounds 50 " " " " 1,300 pounds and over 55 " " " This mode of determining the net weight is to govern only when the beeves are in condition to yield fresh meat of good quality. In the Civil 196 THEOEY AND PEACTICE OF MILITARY HYGIENE. War fresh meat was generally issued upon the hoof, the net weight of the animal being at that time determined by the following rule : From the live weight of a steer there is deducted twenty-five per cent, when the gross weight exceeds 1,300 pounds, and fifty per cent, when it is imder 1,300 and not less than 800 pounds. Where the beeves cannot be weighed it is directed that the animals be divided into three or more lots, graded ac- cording to apparent weight, and that from each lot an average animal be killed, dressed, trimmed and weighed. A satisfactory method for the deter- mination of the weight of an animal, where scales are not available, consists in measuring the length of the trunk from just in front of the scapulae to the root of the tail, and the girth or circum- ference just behind the scapulae; then by multiplying the square of the girth by 0.08 and the product by the length, the dimensions in cubic feet are obtained; each cubic foot is supposed to weigh 42 pounds avoirdupois. The formula is (C' X .08) X (L X 42) = weight; the result is in pounds avoirdupois. The skin is one-eighteenth of the weight; the tallow one-twelfth. In very fat cattle the weight may be five per cent, more, and in very lean cattle five per cent, less than the actual weight found by the above rule. In the British service an ox is ex- pected to weigh not less than 600 pounds, while in the French army the miniTnum is fixed at about 550 poimds. A fat cow wOl weigh from 700 to 750 pounds; a heifer should weigh at least 400 pounds. In the French army a minimum weight for cows to be accepted for food is fixed at 350 poimds. The largest and best-conditioned cattle in our own coimtry come from the ranges of the northwest. Southern cattle, especially Florida cattle and those found in the tropics, are small and lean and their meat is stringy. Where meat is supplied on the hoof and pasturage is abimdant, troops may realize a valuable saving, in quantity and quality, by allowing cattle to recruit from the exhaustion of a long journey and gain flesh by feeding before slaughter. Age.— The best quality of beef is found in animals from four to six years old. Before that time the maximum development is scarcely attained, while later the flesh undergoes deterioration in quality. Cows or heifers intended for slaughter should best be not more than four years old. Where veal is purchased by troops it should preferably be killed between the ages of three and five months ; under six weeks of age veal is imfit for food. Fig. 63.— 1, Lower jaw of calf of eighteen to twenty months ; 2, lower jaw of animal of two years ; 3, lower jaw of beef of two- and one-half to three years ; 4, lower jaw of beef of three and one-half to four years ; 5, lower jaw of beef at flve years ; 6, lower jaw of beef at twelve years. (After Lecoq.) THE RATION. 197 In the living animal, or where the head is attached to the carcass, the age is told with great certainty by the teeth; less accm'ately by the horns. The temporary teeth are in part through at birth, and all the incisors are through in twenty days; the first, second and third pairs of temporary molars are through in thirty days; the teeth are grown large enough to touch each other in six months, and gradually wear and fall in eighteen months ; the fourth permanent molars are through at the fourth month ; the fifth at the fifteenth; the sixth at two years. The temporary teeth begin to fall at twenty-one months and are entirely replaced by the thirty- ninth to the forty-fifth month, the order being — central pair of incisors gone at twenty-one months ; second pair of incisors at twenty-seven months ; first and second temporary molars at thirty months; third temporary molars at thirty months to three years ; third and fourth temporary incisors at thirty- three months to three years. The development is quite complete at from five to six years. At that time the border of the incisors has been worn away a little below the level of the grinders. At six years the first grinders are beginning to wear and are on a level with the incisors. At eight years the wear of the first grinders is very apparent. At ten or eleven years the used surfaces of the teeth begin to bear a square mark surrounded with a white line ; and this is pronounced on all the teeth by the twelfth year; between the twelfth and fourteenth year this mark takes a round form. The appearance of the horns is less useful as a guide, but affords reasonably accurate data upon which to base an estimate of age. According to Laveran, a ridge appears at the base of the horn after the third year, with an additional ridge for each subsequent year. The rings on the horns, however, become indistinguishable in old age ; besides which unscrupulous dealers may file the horns. Condition. — The condition of live cattle is generally told by the han- dling points, of which as many as twelve are given. Of these, however, but five need be mentioned, since an animal satisfactory in these points is sure to be good in the remainder. These points are the natches, or the bones by the side of the tail, the twist, the flank, the udder and the rib. The flesh on all these handling points should feel compact and firm, the twist or parts between the two buttocks should stand out prominently, the flank should be full and appear to meet the hand on passing it over the animal. The rib should be well covered with compact flesh and the cod or udder should be a large lump of firm fat. In half-fed animals the flesh wOl not be so firm to the touch as in fully-fed ones. To be able to properly tell the condition of a beast by handling requires some practice. Health. — As indicating health, the inspector should note the general ease of movements ; the quick bright eye ; the nasal mucous membrane, red, moist and healthy looking; the tongue not hanging; the respiration regular, easy; the expired air without odor; the circulation tranquil; the excreta natural in appearance. Disease is shown by an alteration in the conditions above mentioned. When sick, the coat is rough or standing; Fig. 64.— Horn of Beef Animal Nine Tears Old. (After Laveran.) 198 THEOEY AND PEACTICE OF MILITAEY HYGIENE. the nostrils are dry or covered with foam ; the eyes are heavy ; the tongue is protruded ; the respiration is difificult ; movement is slow and difficult. There may be diarrhoea, scanty or bloody urine or other abnormal symptoms. In the cow the teats are hot. The more common diseases likely to engage the attention of the inspector are pleuro-pneumonia, anthrax, tuberculosis, foot-and-mouth disease, rinderpest and actinomycosis. The nature of any of these affections, if at aU advanced, is usually readily recognized. In time of peace, or when supplies are abundant, diseased animals should invariably be rejected. In foreign countries a disease not likely to injure the health of the consumer is not regarded as sufficient reason for th& rejection of a carcass. In the United States, however, people are more particular in regard to the quality and character of the food they eat than are those of any other country, and there is an almost universal senti- ment against eating the meat of animals affected with any disease, whether the latter be directly communicable to the consumer or not. There is no doubt but that this practice is wise, since in nearly every diseased condition the quality of the meat is inferior. If food is scarce,the flesh of cattle affected with any of the above diseases, save an- thrax, may in an emergency be eaten after thorough cookiag. Dressed Beef. — ^After an animal is slaugh- tered, the organs and flesh should be examined for evidence of diseases that are directly transmissible to the consumer, parasites that may be injurious,, and any other conditions, which, while not directly transmissible, may render the flesh indigestible or toxic and thus produce digestive distmrbances or more severe diseases. The carcass is also examined for the purpose of discovering conditions that ren- der the meat innutritious or offensive — such as chronic wasting diseases, emaciation, old age or immaturity. The manner of cutting up a beef, as well as- the nomenclature of the cuts, varies to some extent with local usage ; but the method shown in the accompanying diagi'am may in general be accepted as correct. For examination by the inspector the carcass is usually divided into quarters. The inspection should usu- ally be made, in temperate climates, twenty-four hours after slaughtering ;. in the tropics it wiU frequently have to be performed immediately after dressing. With marching troops, slaughtering should be done as soon as camp is reached. The meat should be hung up for inspection, since in this way the entire surface is readily observed. If examined on a flat sur- face it may be safely assumed that anything of a doubtful nature which may exist will be found on the under side. Meat found to be of unsatis- factory character should be so marked as to prevent possible fraud on the part of the contractor. The inspection of meat on the block is by no means easy of proper Fis. 65.— Diagram of Cuts of Beef. 1, Neck; 2, chuck; 3, ribs ; 4, shoulder clod ; 5, fore shank ; 6, hrisket ; 7, cross ribs ; 8, plate ; 9, na/- vel ; 10, loin ; 11, flank ; 13, rump ; 13, round ; 14, second cut round ; 15, hind shank. THE EATION. 199 accomplishment, and the sanitary officer should familiarize himself with the characteristics of good meat, qualities to be learned only by actual experi- ence. Good meat, in general, presents the foUowiug characteristics : The lean parts in young, well-fed, healthy animals, after exposure to the atmosphere for some length of time, should be of a bright, clear-look- ing, cherry-red color. Should the cut portion of any meat under inspec- tion have been so long exposed as to become black and dried up, and the general conditions be such that there is a doubt whether the meat is accord- ing to contract, a fresh section should be made. As, however, raw meat freshly cut is always dark in color, no decision should be arrived at until the air has had at least an hour to act upon it, when, if it is as it should be, the color will have changed to that mentioned above. Pale, moist muscle marks the young or sickly animal, the dark colored the old one ; the muscular fasciculi are larger and coarser iu bulls than oxen. A deep purple tiut is said to indicate that the animal has not been slaughtered but has died with the blood iu it. This blood is objectionable, not because it is unhealthful in itself but because it favors rapid decomposition. The lean should have a marbled appearance, due to the presence of adipose material among the muscles. This marbling, however, will be chiefly found in the sections at the ribs and sirloias and wiU. be absent from the sections of the fore and hiad legs or buttocks. The fat should be reason- ably abundant but not in excess, hard and firm; the lean should be full of juice and have a sUky feeling to the touch; the muscles should be firm and elastic, yet not tough. The fat on a carcass is a most important item in judging beef. The exterior should be covered with bright, healthy- looking fat ; the pleura, peritoneum and pelvic cavity should be well fur- nished and the kidneys surrounded with adipose material. In a fattened ox the fat may constitute as much as one-third of the flesh, but the amount varies with the feed of the animal. The meat should possess a pleasant, sweet taste, while the odor should be slight and not disagreeable. When such meat is placed on a white plate a little reddish juice flows out after some hours. In temperate climates the marrow of the hind legs is solid twenty-four hours after killing, and is of a light rosy red. If it is soft, brownish or with black points, the animal has been sick or putrefaction is commencing. The marrow of the fore legs is more diffluent, something like honey, and is a light rosy-red color. In general, variation from the characteristics of good meat, as noted above, wUl indicate flesh of an under- fed, coarse or diseased character: Age. — For determining the age of a dressed carcass no defined signs are available. It is of value to remember, however, that in the young ani- mal the bones are small, soft, porous and of a pinkish color; but as the animal grows older the bones become large, harder; less porous and whiter in color. The inside part of the ribs is very pink in young animals, but as age increases this color fades away and the ribs at about six or eight years old become quite white. The tops of the spinous processes forming the chine are composed of gristle in the yoimg animal, but are ossified about the age of six years. The pubes or aitch bone is only joined by gristle in the young animal, but this ossifies also about the age of six years. Before this gristle has ossified the butcher divides it with his knife in dressing the animal and the blue cartilage is plainly seen in the sides or quarter after- 200 THEOEY AND PEACTICE OF MILITAEY HYGIENE. ward ; but after it has ossified the saw has to be resorted to. By the ninth year all the signs of youth will have disappeared, and the lean, instead of being soft and silky to the touch, will have become tough and stringy. As a rule, there will be a marked deficiency in the quantity of fat, and the carcass in general will present a gaunt, angular and ill-conditioned ap- pearance. Sex. — It is important that the sex of the animal, from which the meat under inspection was derived, should be determined; a matter of no great difficulty if the various points of difference, given below, have been care- fully considered. In the hind quarter of the steer, at the root of the piz- zle, is found the erector muscle, which is about three inches in length by one and a haK inches in breadth. In the bull this muscle is much more fully developed than in the ox, and is much wider, darker in color and coarser in grain. The pizzle in the ox is small and undeveloped, not thicker than the finger. In the bull it is largely developed. It is often split and partly removed in order to make it appear of the same size as that of the ox ; or it may be entirely removed and the retractor muscle left in. There is more cod fat in ox than in bull beef, and in the bull the cavity is gen- erally seen from which the testicle has been removed. In bull meat gen- erally, owing to the superior muscular development of that animal, the proportion of muscular tissue or lean meat is much greater than it is in the ox, and this gives the whole quarter of the bull a darker and redder appear- ance. The lean of the young ox is juicy, smooth and silky to the touch, florid in color and marbled with fat ; but in the bull the marbling is ab- sent, and on touch — a most valuable aid in judging of the quality of meat — the coarseness, stringiness and toughness of the texture is easily detected by passing the thumb or finger gently over the cut siu- face of the lean. The fat, though less plentiful in the full-grown bull, will be of a distinctly whiter color than that of the ox. No matter how well a bull is fed, the proportion of fat to lean is very considerably less than in the steer; in fact, an old bull has hardly any fat at all on his carcass, and what there is will be found almost entirely on the hind quarters. The chief distinguishing features of a fore quarter of an ox from that of a buU is the collar or crest, which in the buU is very large and muscular, requiring at least the whole hand to grasp it, but in the ox is very much smaller and can be grasped between the forefinger and thumb. The quarters themselves are narrower and slighter than those of the ox ; but in general the bony structure, and especially the aitch bone, is very much more massive in the bull. Young cows are rarely killed for beef, for if in good health they possess much greater value for dairy or breeding purposes. When young and in good condition the flesh is silky and juicy to the touch and possesses all the attributes of good beef. Iii distinguishing cow from heifer beef the udder is the sign usually relied upon. In the heifer this gland is but slightly developed ; it is surrounded by fatty tissue and forms a uniform thick wall on either side of the flank. After the delivery of one calf the surface of the udder will be slightly soft, but the main portion will stiU consist of adipose tissue and the small millv -ducts wUl just be visible. After the second calf the udder wUl be partially composed of a tough, brown, spongy substance and partly of fine fat, while the milV ducts will Plate .VII. Fig. Fig. 1 , Hvrui.-quxxrte;r of Cow orHa/er; „ Z,HiiwL-quM7-terofBtdt ,1 3 , HiTLdrqiicLrter' of Ox. (Afier Natter and Firth) THE EATION. 201 be much more prominent. As the number of calves increases, the udder becomes looser, browner and more spongy in appearance. To make the hind quarter of a cow resemble that of a heifer the udder is sometimes cut out while the carcass is warm and the skin is then skewered neatly over the excised part. The fraud is at once exposed by removing the skewers, and a quarter tampered with ia this manner should be promptly rejected. It is very difficult to teU the fore-quarter of a heifer from that of an ox. The pelvic bone of the old cow is unmistakable. As age iacreases, the portion nearest the udder gradually wears away and becomes narrower, while that nearest the haunch generally broadens considerably. The fat of the old cow is usually deficient in quantity and of a brighter yeUow than that of yoimg animals ; though the latter fact, unsupported by other evidence, is not sufficient cause for rejection, as it may be attributable to breed or feeding. The flesh iu old cows is generally coarse, dry and stringy. In the fore-quarter the chief indications that the animal is old are the bleached ribs, want of fat on the ribs and pleura, and a very promi- nent scapula or shoulder bone, with a hollowness or falling away on either side of it which gives a concave or " shelly " appearance to the quarter. Quality. — Carcasses of animals that are slaughtered shortly after com- ing off ship-board, especially in bad weather, or have been transported long distances in crowded cars, are sometimes found to be much brtdsed and occasionally to have abscesses ; the bruised parts may be cut out and the healthy part issued. The flesh of animals killed on account of acccidents is usually dark and discolored by reason of not having been bled, the tho- racic and the abdominal walls are stained from contact with the viscera; the odor is offensive and there is discoloration from incipient decomposi- tion. Most meat of this class should be condemned. If the injuries are localized and the animal is at once slaughtered, the carcass being properly dressed, the undamaged parts are normal in condition and may be eaten without injury. The flesh of over-driven animals is harsh in character, has a strong, peculiar odor and is wanting in that juicy characteristic noticed in good, well-fed animals which have been rested before slaughter. The color of such meat is dark, rigor mortis begins early, decomposition is rapid and the muscles are highly acid. The flesh of over-driven and ex- hausted animals is said frequently to produce diarrhoea when eaten. In certain tropical countries it is customary to work cattle on the yoke for some years and then fatten them for market purposes. Such animals are habitually driven with sharp goads instead of whips, and, on slaughtering, the muscular tissue is found to contain cicatricial nodules or cavities, hold- ing pus or detritus resulting from the injuries produced by the free use of these goads. In commencing putrefaction the color of the meat becomes paler. The consistence is altered and some parts of the meat are softer than others, tearing apart readily when stretched. A greenish tint may be later appar- ent and the putrefactive odor is marked. Taint in suspected meat is best found by plimging a knife or clean wooden skewer into the thickest part of the flesh and observing the odor acquired. This precaution is especially necessary in warm weather. The meat of healthy animals, when slightly decomposing, may often be eaten without danger ; but occasionally it gives 202 THEOEY AND PEACTICE OF MILITARY HYGIENE. rise to gastro-intestinal disorders, vomiting, diarrhoea and great depression. In some instances severe febrile symptoms occur, accompanied by marked cerebral complications. These effects are produced by the ptomaines re- sulting from the action of the micro-organisms of putrefaction ; cooking appearing to have Kttle or no influence in destroying the toxic properties of the ptomaine. Fresh meat, derived from unsound animals, has not infrequently given rise to severe toxic symptoms, particularly if kept in dark, imwholesome and poorly ventilated places. The poisonous qualities of the meat appear to depend upon the formation of a ptomaine resulting from the action of a specific bacillus — the Bacillus enteritidis — first discovered by Gaertner in the flesh of a cow affected with severe diarrhoea ; the meat of this animal having given rise to severe toxic symptoms in those who had partaken of it. This bacillus grows easUy on ordinary media and is very fatal when injected subcutaneously into rabbits and guinea-pigs. It has since been isolated by other observers in a considerable number of cases of poisoning by bad meat. Veal appears especially liable to undergo change in the formation of ptomaines. According to Laveran, of 30 epidemics of intoxi- cation fi-om fresh meat occurring in France, 14 of them resulted from the use of fresli veal — a proportion extremely high when it is considered that veal is not a common staple of diet but rather an article of luxury. In one outbreak mentioned by this writer, occiuxing in the Seventy-second Eegiment of the line, of 147 men who partook of some poorly cooked veal no less than 135 became sick; 10 cases were extremely serious and 2 deaths resulted. Sausages, meat pies and hash, even when made from meat of appar- ently wholesome character, are liable to undergo fermentative changes in the formation of ptomaines, especially when allowed to stand in warm weather or placed in covered dishes, near a fire, over night. Hash prepared the night before it is to be eaten is particularly prone to such changes, and outbreaks of intestinal disturbances, varying from simple diarrhoea to marked choleraic symptoms, have not infrequently followed the use, in our own service, of such preparations. At Fort Sam Houston, in 1888, out of a company of the Nineteenth Infantry twenty-eight men were reported as having suffered from ptomaine poisoning; while at West Point and Walla Walla, in 1898, an entire company in each post was prostrated from the use of stale hash. At West Point, in 1895, fifty-four cadets were affected with ptomaine poisoning from a similar cause. Many other outbreaks of this character have also been reported. The symptoms of ptomaine poi- soning usually follow rather closely on the ingestion of the meat, but may be delayed as much as thirty-six horns. In character, when severe, the symptoms closely resemble those produced by irritant poisoning and are accompanied by marked nervous depression and coUapse. The ptomaines appear to resist a comparatively high temperature — and hence cooking, even when thoroughly carried out, does not render them harmless, even though it destroys the micro-organisms to which they owe their origin. It should not be forgotten, in this connection, that a return to a fresh meat diet from salt rations often induces diarrhoea, frequently very free in character. This, however, does not occur if the meat is eaten at first in moderation. Among the transmissible affections to which beef cattle are liable, THE RATION. 203 Man iTy gn ^ Sa g, i Fig. 66— Life Cycle of the Beef Tapeworm. (After BoUiiiger.) capable of influencing the health, of man, the most important are the occmrence of cysticerei, tuberculosis and anthrax. Cysticercus Disease. — When the Cysticercus bovis is present in beef the latter is known as " measly " — ^the life history of the parasite beiag as follows : The eggs of the beef tapeworm, Taenia mediocaneUata or saginata, are expelled with the dejecta of its host and do not undergo further development unless entrance be obtained to the alimentary canal of the ox. From here the em- bryo, liberated by the digestive juices, passes into the voluntary muscles of the animal, where it re- mains as the bladder-worm or Cysticercus bovis. An ox affected with this parasite may contain many hundreds of such cysticerei within its mus- cles. In the living animal the cysticercus is sup- posed to survive for several years, but it ordinarily dies about fomrteen days after the death of its host ; this fact having especial importance in connection with the storage and refrigeration of meat. It is kUled by exposure to strong brine for twenty-four hours and is unable to withstand a tem- perature of 140° F. for five minutes. In ordinary salting, however, it requires some time for the brine fully to penetrate the tissues. On the flesh of the afi'ected animal, either raw or imperfectly cooked, being taken into the alimentary tract of man, the cys- ticerei develop into the sexually complete taeniae and the life cycle of the parasite is completed. The cys- ticerei are usually most numerous in the haunch and closely resemble those foimd in "measly " pork, here- after described ; but are said to be much more difficult to detect, since, according to Laveran, they rapidly disappear under exposm-e to the air, by desiccation, and their presence may be overlooked unless care is taken to examine- a fresh piece of meat. To render the cysticerei more apparent it is frequently of advantage to moisten the surface of the meat to be ex- amined. The head of the cysti- cercus of the ox is relatively larger than the cysticercus of pork; it is provided with four strong, prominent suckers, but lacks the booklets char- acteristic of the cysticercus of the hog. In case of doubt the suspected cysticercus may be taken between the fingers and gradual pressure exerted, this causing the protrusion of the head, upon which the four suckers are readily distinguished. The only parasites in cattle liable to be mistaken for "measles" are Cysticercus tenuicoUis and Echinococcus polymorphus. Neither of these parasites is directly transmissible to man. " Measles " is said to be particularly common in the cattle of India and -.4 Fig. 67.— Cysticerei bovis: in muscle; B, devel- opmental form, head everted. (After Leuc- kart.) Fig. 68.— TMn- Necked Bladder Worm, Cys- ticercus tenuicolUaT with Head Extruded from Body. Natural size. 204 THEORY AND PRACTICE OF MILITARY HYGIENE. Abyssinia, and Laveran states that infection by the beef tapeworm is very common among the French troops in Algiers and Tunis. The same writ- er states that one-fifth of the beef cattle slaughtered at the military abattoirs in Tunis are affected with cysticerci. In the United States and England the beef tapeworm is said to be much more frequent than the pork tape- worm ; probably from the common habit of eating rare beef and the greater care given to the thorough cooking of pork. In the United States army, during the Civil War, there were noted 566 cases of tapeworm; while for the period of twenty-seven years, 1868-94, tapeworm was reported as occurring in 1,280 cases, giving a yearly average of 47.4. No differentia- tion in diagnosis appears to have been made between infections by T. mediocaneUata and T. solium, but it is extremely probable that most of the cases noted were due to the former parasite ; especially since trichino- sis, common in American swine, was very rare in our army during the same period, this fact showing that pork is ordinarily sufficiently cooked to destroy any contained parasites. During the years 1895-97 the cases of "taenia and other intestinal parasites " numbered 114; and for 1898 there were 50 such cases reported. In the British service in India the rate of admission for tapeworm was 9 per 1,000 for 1898, 11 for 1897 and 11 for the decade 1887-96. In 1898 there were reported 162 cases of Taenia solium and 6 for Taenia mediocaneUata. In the Bombay district alone, in 1898, the admissions for taenia were no less than 24 per 1,000. These figures show the importance of more careful inspection and better cooking of meat in our service ; particularly since troops serving in the tropics will often be forced to rely upon native beef, well known to be largely affected with cysticerci. There appears to be no way by which the presence of cysticerci in the ox can be definitely determined during the life of the animal. By exam- ining the under side of the tongue it is occasionally possible to find small lumps which can be moved by the fingers and which may represent cysti- cerci. It is rare, however, that this method leads to practical results and no rehance should be placed on it. Tuberculosis. — Tuberculosis is a very common affection among cattle, especially among mature animals, thus showing that the influence of con- tagion is more to be feared than that of heredity. It is more frequent in stabled cattle than those allowed to range freely, and varies in frequency with locality. In the United States it has been determined that from twenty to thirty per cent, of milch cows are tuberculous, even those under the best sanitary conditions. The meat inspections of Berlin showed that no less than twenty-five per cent, was tuberculous. The proportion of tuberculosis in calves is much lower than in cattle ; varying according to the age and the locality, but averaging about eight per cent. In England twelve per cent, of beef is found to be tuberculous, while in Mexico as much as thirty-four per cent, appears to be so affected. In France tuberculosis in cattle does not appear to be relatively common. Bovine tuberculosis is compatible, unless well advanced, with the main- tenance of apparently good bodily condition; and it is usually impossible to diagnose the affection in the living animal by the ordinary methods of physical examination. There may be no visible symptom of the disease in the animal unless in the case of an acute attack, when there is always THE RATION. 205 fever and rapid wasting of the body. When the disease attacks the external organs, such as the udder, there is generally no constitutional disturbance ; this is much more likely to be present when the internal viscera are affected, but an animal may be extensively diseased and yet exhibit no symptom to call for special attention. Since the discovery of Koch's tuberculin, however, a safe and reliable means of diagnosis is always available, and by the use of this test the proportion of affected cattle has been found to be much greater than was formerly supposed. Brewer states that all competent authorities consider the test unerring; while Pearson states that of a very large number of animals which responded to this test and which were afterward slaughtered, aU presented tuberculous lesions on post-mortem examination. According to De Schweinitz, the tuberculin employed in the Depart- ment of Agriculture is prepared in the following manner : One pound of finely chopped lean meat is added to one liter of distilled water, to which is also added one per cent, of peptone, one-fourth of one per cent, of salt, and seven per cent, of glycerin. The whole is heated to boUing and filtered. The filtrate is stored in sterilized flasks and sterilized on three successive days. After the cotton plugs of the flasks have become dry, they are removed, dipped in melted paraffin and replaced in the flasks so as to make tight stoppers. The inoculation of the media with the micro-organism is accomplished in the usual manner, using a pure culture of tubercle bacilli grown for several weeks on glycerin-agar or potato. A bit of the spongy growth so formed is detached by the platinum loop from the jelly or po- tato and carefully floated on the surface of the nutrient liquid; if com- pletely immersed it will sink, and the bacilli, in the lack of oxygen, wiLL not develop. The flask is then kept at a temperature of 98° F. until the surface of the liquid is covered with a growth of bacUli, this usually occm'ring in about ten days. When this is noted, the flask is carefully shaken, causing most of the growth to sink to the bottom of the liquid but leaving a small particle on the smrface to serve as a nucleus for a new growth. The second growth is shaken down as in the first instance and a third growth allowed to form. This process will require six weeks to two months from the time the flask was first inoculated, and the contents are then in a condition for the preparation of tuberculin. The flask is then placed in an oven at 125° C. and allowed to remain until its contents begin to boil. It is then removed, its contents are carefully filtered and the residue on the filter paper is washed twice with distilled water. The filtrate and washings are then concentrated by evaporation down to one-fifth of the original volume. In the work of the Department of Agriculture, in- stead of sending out concentrated tuberculin, it has been found advisable to dilute it to such a strength that 2 c.c. wOl be a suitable dose for the purpose of diagnosing tuberculosis in cattle. To accomplish this dilution there is added, to the concentrated tuberculin, glycerin equal to one-fourth the original bulk of the culture liquid. This is then diluted with one- fourth of one per cent, carbolic acid, so that the volume of the tuberculin usually obtained is one-fourth more than the original quantity of crdture media used. In other words, 1,000 c.c. of ciilture media, after the germ has been allowed to grow sufficiently long, diluted with the proper amount of glycerin and carbolic acid, should give 1,250 c.c. of tuberculin of such 206 THEORY AND PEACTICE OF MILITAEY HYGIENE. a strength, that 2 c.c. would be a satisfactory dose for testing an animal of one thousand pounds iu weight. Several methods of standardization of the tuberculin are employed. The amount of the tuberculin required to produce a rise of four or five degrees in temperature in tuberculous guinea-pigs of one pound in weight is noted ; or the quantity of tuberculin found necessary to kill a tuberculous guinea-pig; or, again, a standard upon a chemical basis, depending upon the amount of acid which is produced by the growth of the bacilli,' is used. All tubercle cultures after they are well grown show a decided acid reaction. If the reaction of the media is carefully noted before inoculation and again after the growth of the germ, it is found that the amount of acid reaction is increased proportionately to the quantity of the growth. By practice it 'is also found that this is approximately constant. If the value of a tubercu- lin made from a culture ia which the acid reaction has been carefully tested is once noted, it serves as a guide for future work. In practice it has been found that healthy animals do not give reactions with large doses of tuberculin, and that as a rule tuberculous animals do not show an appre- ciably higher reaction with large doses of tuberculin than with medium doses ; hence, while the above methods of standardization are not so accu- rate as those which would have to be used in weighing out a very poison- ous alkaloid, experience has shown that they are sufficiently accurate for ordinary work. If the animal is diseased, from six to eight hom:s after the injection of the tuberculin the temperature begins to rise from the normal, which in cattle varies from 101° to 102° F., and should continue to rise imtil it has reached 105° to 107°. A reaction of two degrees Fahrenheit above the normal may be considered as good evidence that the animal is infected with tuberculosis. The febrile reaction in tuberculous cattle, following the injection of tuber- culin, reaches its maximum niae to fifteen hours after the injection. The temperature should be taken every two hours, beginning six hours after the injection and continuing eighteen hours. Each adult animal should receive 2 c.c. of the tuberculin diluted by the above method. Yearlings and two year olds should receive 1 to 1.5 c.c, according to size. Bulls and very large animals may receive 3 c.c. The injection is made beneath the skin of the neck or shoulders ; no marked local swelling usually occurring at the seat of injection. There are, now and then, uneasiness, trembling and the more frequent passage of softened dung. There may also be slight acceleration of the pulse and of the breathing. A rise in the temperature on the day following the injection, of two or more degrees Fahrenheit above the maximum observed on the previous day, should be regarded as aniudication of tuberculosis. For any rise less than this a repetition of the injection after three to six weeks is highly desirable. It must not be forgotten that tuberculin condemns many animals in whom the disease may have but a slight foothold ; a tubercular nodule, small and confined to a bronchial gland, may give rise to a reaction as in- tense as if the animal were affected with a generalized tuberculosis. On the other hand, some tuberculous animals, after reacting several times to tuberculin, no longer react and may be marketed as healthy. It is not clear how such fraud can be prevented. In bovine tuberculosis the muscular tissue is less frequently affected. THE RATION. 207 Nocard states that of one hundred diseased animals examined, the lesions were found in the lungs and pleura in forty, in the lungs alone in twenty- five and in the serous membranes in twenty; the lesions in the remainder being generalized or located in the lymphatic ganglia, the genital organs, the bony system or other parts. Tumors of the lungs, variable in dimen- sions and often calcified, are formed by the agglomeration of tubercles. They are hard, resistant and crackle under the knife. On section, then- tissue appears of an intense yellow color and is rough to the touch. Some- times the tubercles present an obscure fluctuation and incision allows the escape of a thick, yellow, lumpy matter. The ordinary miliary tubercles are foimd around the tuberculous masses. The bronchial glands are also invaded where the limgs are affected ; they are hypertrophied, hard and nodular, and on section appear like cheesy matter infiltrated with lime salts. The tubercles often cover the serous membranes. They appear like little tumors, roimd or mechanically flattened, hard, firm and white; sometimes disseminated over the serous membrane but often assruning the form of grapes, cauliflower or polyps, and many acquire considerable size. In inspecting beef carcasses care should be taken to observe the presence of the pleural and peritoneal membranes. In tuberciilosis or pleuro-pneu- monia there are almost invariably adhesions of the lung and pleura. Ex- amination of the pleuia wiU reveal this, or else there will be distinct evi- dence of the knife having been used in the attempt to remove the evidence of their existence. The under side of the diaphragm should also be care- fully examined, and, if the coating of either this or the ribs be removed, the carcass should be rejected. No weight should be given to statements to the effect that this stripping is the result of endeavors to remove the unsightly appearance caused by " over-sticking " or " body-sticking," other- wise, unskilful bleeding; the contractor is responsible for the skiU. of the men he employs and must be prepared to take any loss arising from their carelessness. In the udder, tuberculosis is characterized by sclerosis. In the centre of the tissue there is a new formation of finely granular tuber- cles; these slowly coalescing into a more or less voluminous mass, which imdergoes cheesy degeneration and calcification. The characteristic baciLLi have not infrequently been found in the fluid expressed from infected muscular tissue; they have also been observed in the blood and in the secretions of diseased organs. Feeding-experiments made with raw meat from tuberculous animals, from which the outwardly diseased portions had been removed, show that thirty-six per cent, of pigs kept on this food became tuberculous; the most frequent seat of infection in such instances being the lymphatic glands of the throat. A practical objection to the use of any parts of tuberculous animals as food consists in the fact that butchers are ordinarily careless in the cutting up of car- casses, and tuber cidous matter may find its way to the knives used and be transferred by them to portions which might otherwise have remained uncontaminated. It has been shown also that even when the disease is localized the blood may contain bacilli, and in this way the meat may be throughout a source of danger. Woodhead experimented in roasting and boiling meat smeared with tuberculous matter and found that rolls of such meat, over three or four poimds in weight, were not sterilized by the ordinary means of cooking. Eoasting was the least and boiling the most -effective 208 THEOEY AND PRACTICE OF MILITARY HYGIENE. method of destroying the bacilli. As a corollary to the points brought out above, the necessity for the thorough cooking of fresh beef, in aU instances, becomes evident. An official decree was promulgated by the French Government in 1888 forbidding the sale of tuberculous meat : (1) If the lesions were general- ized; (2) if the lesions, though localiiied, had invaded the greater part of an organ, or were manifested by an eruption on the walls of the chest or of the abdominal cavity ; such flesh was not to be used for feeding animals but must be destroyed. In Austria, when the affection is localized the remaining meat is passed as healthy. According to a recent Eussian re- script, the flesh of tuberculous cattle is looked upon as dangerous to health either when the flesh contains tuberculous nodules or when the tubercu- lous animal is in poor condition, even if no such nodules are present in the flesh. For the military service, in time of peace or when an abundance of provisions can be secured, the flesh of animals which react to the tubercu- lin test, or which present the characteristic lesions of the disease, even if slight, should be rejected. In time of scarcity the apparently sound portions of meat of slightly afl^ected animals, if otherwise in good condition, need not necessarily be condemned — but special care should be taken to insure thorough sterilization by cooking. When the lesions are generalized, the flesh of tu- berculous animals should under no cir- cumstances be used as food. Anthrax. — ^Anthrax occurs in cat- tle, sheep, horses and sometimes pigs. The disease is rapidly fatal and the ma. 69.— Bacim of Anthrax m Blood. (Alter affected animal may die in a few hours. Abbott.) .„ . '' . . , The specific micro-organism associated with this disease, the Bacillus anthracis, is found chiefly iu the blood and spleen of affected animals. It is rod-shaped, multiplies by division, and when injected into other animals produces the characteristic symptoms of the disease. In animals affected with anthrax, -the liver, kidneys and spleen are congested. The spleen is enlarged, dark and frequently found to be ruptured. In the more localized affection, " black quarter," there are general hemorrhagic effusions into the subcutaneous or intermuscular tis- sues of the affected member. When boils and carbuncles form they are at once recognized. The flesh of animals affected with anthrax presents in high degree the appearance of meat taken from an animal sick with fever, but the specific nature of the condition cannot always be detected by mere inspection. An examination of the blood under the microscope shows the characteristic micro-organism; but the examination must be made shortly after death to prevent the bacilli of anthrax being confounded with the common bacilli of putrefaction, which develop with extraordinary rapidity. In the blood the bacillus of. anthrax is short and rod-lilie and does not develop into the long filaments seen in artificial cultures. Anthrax is particularly dangerous because the germs circulate in the THE EATION. 209 blood and reach every portion of the body. They are certain to be ia every part of the meat taken from the carcass. Further, the bacilli of anthrax form spores when the carcass is dressed and the oxygen of the air comes in contact with the meat. These spores resist a very high tem- perature and may not be destroyed by cooking. It has been claimed by some that the flesh of animals affected with anthrax, if well cooked, is not dangerous ; and it is certain that such flesh has on several occasions been eaten with impunity. Its manipulation, however, is fraught with great danger prior to cooking, and many instances have occurred in which inoc- ulation from the carcasses of diseased animals has taken place. Many cases have also occurred in which the flesh of animals affected with anthrax has given the disease ; and inoculations made from the centres of affected roasts or steaks, after cooking, have abnost invariably given positive results. Not only should the flesh of animals affected with anthrax be rejected as food, but it should be carefuUy destroyed, preferably by fire. Actinomycosis. — ^This disease, also known as " lumpy jaw " in cattle, is ordinarily at once recognized by the eye from the characteristic deformity of the jaw which it produces. In doubtful cases the nature of the disease is readily determined by the microscope. The disease may also attack the lungs and bones. When the affection is advanced, the emaciation of the animal is usually great and the flesh is imfitted for food. In the early stages, when the affection is distinctly localized, the quality of the meat is not seriously impaired. The disease appears to be particularly common among range stock. Other Diseases. — In cattle-plague, or rinderpest, the meat is seriously affected and is quite imfit for human consumption. In the sieges of Strasbourg and Paris, however, in 1814, many of the animals used as food had rinderpest and yet no evil consequences ^'*'- ^--Actinomyces, apparently resulted. This disease was extremely pre- valent among the beef herds accompanying the invading Prussians in 1870-71, and many animals died from this cause. It is understood that, where possible, the German authorities made no use of the meat of such animals, regarding it as being of a dangerous character. Texas fever is a common disease of cattle in the United States. The appearance of the meat is that induced by any febrile affection. The flesh is imdeshable as food ; but it may be used without harm, after thorough cooking, in an emergency. Epidemic pleuro-pneumonia is a disease peculiar to cattle, and is a contagious inflammation of the lungs and pleura; it has never been 'trans- mitted to other than bovine animals. Its effects are localized in the lungs alone, and even in these organs the disease is a limited one. In the ad- vanced stages, and when a large area of lung tissue is destroyed, with ex- tensive pleurisy, the flesh becomes altered in color and consistence. Notter and Firth advise that the carcasses of animals affected with pleuro-pneu- monia be passed as innocuous, if they present no departure from natural conditions. Acute rheumatism in cattle is sometimes known as " joint-Hi " or, 14 210 THEOEY AND PRACTICE OP MILITARY HYGIENE. "joint-felon." The serous fluid effused into the joints may become puru- lent, and abscesses may sometimes be found in the neighborhood of the affected joints. The meat becomes dropsical and the carcasses of animals so affected are totally unfit for hmnan food. Laveran, Notter and Firth and others give a number of instances in which typhoid fever has apparently followed the use of meat of bad quality. In such cases the typhoid baccilli must have subsequently gained access to the blood and found conditions favorable for their development. It is, of course, impossible, in the light of our present knowledge, to admit that the meat of a diseased animal is capable of directly originating true typhoid. The flesh of feverish animals undoubtedly contains an abnormal quantity of leucomaines and perhaps of toxines, which are liable to affect the diges- tive organs, particularly in hot weather, and to cause illness in the con- smner which is mild or severe in the latter, according to his condition at the time of partaking. According to Miller, meat derived from animals affected with, febrile diseases is more or less dark and of a dull tint; the adductor muscles of the thigh usually being gray, earthy or yellowish. The serous membranes of the abdomen and chest are furrowed with hypo- static discolorations of a gray or livid color ; a purplish discoloration of the loins is rarely absent. The fat shows vascular injections, giving the ap- pearance of being streaked with wine. The smell is unpleasant and cadav- eric, especially on incision of the thighs and shoulders. The muscular tissue is lacking in flrmness, and in long-standing diseases the tissues are bathed in serum ; the flesh is wet and pale, and rigor mortis does not read- ily take place. Such meat has a mottled appearance, readily " pits " on pressure and has not the elasticity of ordinary flesh. Meat of this char- acter should invariably be rejected in time of peace; in severe straits it is better to issue it than allow troops to starve. It is said that melted fat is sometimes rubbed over the carcasses of thin and diseased animals to give the characteristic glossy look of health. When medicines have been given, diseased meat may present the odor of physic, very evident when the meat is chopped up and drenched with hot water. Meat of this character has been known to produce in man the characteristic symptoms of the medicine administered. Mutton.— i'resh mutton, in the same quantity as beef, forms part of the legal ration. It is by no means suited for use as a steady diet, and only as an occasional issue is it relished by troops. Even when mutton of the best quality is available the issue of beef is almost always preferred by the men. A sheep yields about sixty per cent, of flesh available as food. A full-grown animal will weigh from sixty to ninety poimds, but the difference in breeds, in this respect, is very great. Sheep under fifty pounds should not ordinarily be received, since those under this weight tendered for issue are likely to be of inferior quality. The chief character- istics of good mutton are almost the same as in beef ; and the general in- dications as to sex in sheep can be told much the same way as in cattle. The ram in relation to the wether presents much the same appearances as the bull in relation to the ox. The pizzle of the ram is about twice as thick as the ordinary lead pencil, while the pizzle of the wether is not more than half that size. In the ram the neck is very broad and massive as compared with that of the wether or ewe. The thick neck in the ram THE RATION. 211 con-esponds to the crest of the bull ; and the butcher may remove it and attempt to pass the remainder as contract mutton in the same way as the neck of the bull is sometimes cut off with a view of masking the sex. Carcasses of mutton mutilated in this manner should be unhesitatingly I'ejected. In live animals, or where the head is attached to the carcass, the age may be told with accuracy. The temporary teeth begin to ap- pear in the first week and fiU the mouth at three months; they are gradually worn and fall at about fifteen or eighteen months. The fourth permanent grinders appear at three months and the fifth pair at twenty to twenty-seven months. A common rule is "two broad teeth every year." The wear of the teeth begins to be marked at about six years. Sheep fit for slaughter should always have a clean, even set of teeth ; in the British army those with broken teeth are rejected. Should the back of a carcass present a gen- erally discolored and veined appearance it is probably the result of age and want of condition, and the meat should be rejected. It very frequently happens that mutton tendered by contractors is extremely fat, the proportion of fat to lean being so great as to give rise to complaint on the part of the men. Mutton suet suffers a large wastage in cookiag; further, it imparts a disagreeable odor and tallowy taste to the meat. The amount of fat on a carcass may be determined, without cutting it through, by inspecting the region of the shoulders. If a bluish tinge is discernible the proportion of fat is not too great. If, on the other hand, this tinge — which is the lean showing through the covering of fat — is absent, the carcass is too fat, and the contractor should be required to strip off some of the covering of the back as well as the surplus fat about the kidneys. It is best to see personally that this is done, since otherwise only a very superficial trimming will take place. Should the contractor refuse to remove the surplus fat the carcass should be rejected. The average chemi- cal composition of mutton is as follows : Diagram of Cuts of Mutton. 1, Neck ; 2, chuck ; 3, shoulder ; 4, flank ; 5. loin ; 6, leg. Tig. 72.— Dlstomum Hepaticum. Water, per cent. Protein, per cent. Fat, per cent. Fuel value per pound, Calories. 43.8 16.3 22.3 1,152 The diseases affecting sheep are similar to those of cattle. Of these anthrax is the most important. Sheep also frequently suffer from acute pulmonary troubles, hsematuria and other diseases. Of the chronic lung affections, one of the most im^jortant is the so-called phthisis, which is pro- duced by the ova of strongylus filaria. The entozoon has not yet been found in the muscle, and the meat is said to be good. The Distomum hepaticum is frequently found in the livers of sheep, which may contain large num- bers of this parasite. The number of cases of human infection by this 212 THEORY AND PEACTICE OF MILITARY HYGIENE. parasite are not large, but they are sufficiently numerous to indicate that they may be the cause of severe, though not often fatal, disorders. The affected liver should in all cases be destroyed, and the carcass condemned if it be deteriorated in quality ; this being usually the case in advanced stages of the disease. The flesh of a young, well-fed goat which has been properly castrated when young, or of a maiden female goat, is so much like mutton that it is extremely difficult to tell the difference when cooked. Pork. — The chemical composition of some of the more important cuts of fresh pork, as purchased, is as foUows : Cut. Water, per cent. Protein, per cent. • Fat, per cent. Fuel value per pouud. Calories. Ham 45.1 40.8 44.9 14.3 13.3 13.0 39.7 36.0 39.8 1,530 1,340 Shoulder 1,480 While not included ia the ration, fresh pork at contract price for beef will give pleasing variety and prove an economy when it can be kept. The lard may be rendered and all unconsumed grease preserved for culinary use, thus saving an otherwise necessary purchase from the commissary. Under-done pork, however, may cause erythema and urticaria, and such pork is always a source of danger through the ai^imal parasites which it may be in a condition to transmit. The flesh of ap- parently healthy pigs has not infrequently caused diarrhoeal outbreaks, which at times have even assumed a choleraic character. In 1896 a severe outbreak of this character occurred at West Point, affecting twenty-five men. Hogs, when full grown, weigh from one hun- dred to one hundred and eighty pounds or more, and yield from seventy-five to eighty per cent, of available food, of which as much as one-half may be fat. Old or diseased swine should be rejected. The age of the pig may be told up to three years by the teeth ; after that there is no certainty. The temporary teeth are complete in three or four months; about the sixth month the pre-molars, between the tusks and the first pan- of molars, appear; in six to ten months the tusks and pos- terior incisors are replaced ; in twelve months to two years the other incisors; the four permanent molars appear at six months ; the fifth pah- at ten months ; and the sixth and last molars at eighteen months. Hogs are frequently kept by companies at military posts, being fed on kitchen refuse and a certain amount of grain. This practice has its advan- tages from an economic standpoint, but the styes and their surroundings are almost invariably allowed to lapse into such bad sanitary condition as FI8. 73.— Diagram ot Cuts of Pork. 1, Head; 3, shoul- der; 3, back; 4, middle cut; 5, belly; 6, bam; 7, ribs; 8, loin. THE KATION. 213 to render the keeping of hogs by troops qiiite inadvisable. The flesh of swine fed on garbage is qiiite inferior to that of grain-fed animals ; and Gamgee states that pigs fed on flesh have a peculiarly soft, diffluent fat and emit a strong odor from their bodies. The pig is not infrequently at- . tacked by swine fever ; more rarely by anthrax. Cobbold showed that the flesh of the pig, especially the fat, sometimes contains a large parasite, Stephanurus dentatus. The worm is at first free and then encysted ; the cyst is large and |may be one and three-fourth inches in length and one- half inch in diameter. The full-grown worm may be as much as one and one-half inches in length. Three to six eggs are found in the cyst ; the young worms migrating into the surrounding tissue after hatching. This parasite is not known to induce disease in man, although its presence in flesh intended for food is certainly undesirable and may be a cause of apprehension to inexperienced inspectors. Its true nature is readily deter- mined by the microscope. Pork Measles. — The eggs of the pork tapeworm, or Tsenia solium, after being expelled from the affected person, are not infrequently taken up by the hog. In the latter event the contained embryo is liberated, passes into the muscular structure of the animal and becomes metamorphosed into the blad- .-taan^So; ; der worm," or Cysticercus cellulosse, giving rise to the appearance known as "measles." The embryo remains in the flesh imtil the death of the animal acting as host, or until it passes with the flesh of the animal, used as food, into the stomach of man, when it develops into the mature tapeworm identical \v^^^ ^^ \Man with that from which its life cycle was Hog (Cyst.CeU.) begun. It should not be forgotten that the ^^^- ^'^' eggs of the Taenia solium, when taken in by ^'''- ''^■""^'Ste/BomngerT"' "'"'""' man, undergo development the same as in the hog; man thus serving as the intermediate host of the cysticerci. As showing its frequency. Stiles states that the proportion of cases of Cysticercus ceUulosae, occurring in cadavers dissected in Berlin, fell from 1:31 before the introduction of meat inspection to 1 : 280 after a system of meat inspection was instituted. Where the number of cysticerci is small the resulting symptoms are insignificant and obscure. Where the number of parasites is large the condition of the individual acting as host may be- come serious. Satisfactory statistics as to the proportion of pork measles in American hogs are lacking. During life there are few indications of the existence of cysticerci in the animal. The only positive sign to be obtained is in the mouth, where the cysts may sometimes be detected on the base and sides of the tongue, or between this and the lower jaw. According to Laveran, these cysts may be caused to disappear by pricking with a needle; he stating that this practice is not infrequently resorted to by unscruprdous dealers. The body of the affected animal may have a soft, flabby feeling, and on firm pressure a crackling sensation may be imparted to the fingers. The latter signs are unreliable. " Measles " in pork are readily recognized by the eye when the cysti- 214 THEOEY AND PRACTICE OF MILITARY HYGIENE. cerci are numerous. These appear in the flesh as smaU, somewhat elon- gated gelatinous cysts, usually about the size of a pea, lying among the muscles. The cysts may be so numerous as to cause the flesh to crackle under the knife. Sometimes they are present in the liver ia large num- bers, giving that organ a mottled appearance on section; and Stiles states that as many as twenty thousand may occur in a single carcass. They are readily enucleated by pressure, leaving a cavity. When the meat is cooked, the cysts become opaque and pearly white. "Measly " pork has a pale, flabby appearance and is soft and apparently dropsical. The tongue, heart, intercostal muscles and neck are the parts most frequently affected, Flo. 75.— 1, Cystlcercl In muscle ; 2, cystlcerci removed from muscle ; 3, external coat opened to show para- site ; 4, body of parasite extruded from cyst ; 5, longitudinal section, showing parasite in situ ; 6, ex- ternal coat opened to show inner lining containing parasite ; 7, 8, Inner coat cut open and parasite ex- truded ; 9, cystlcercus, with head, neck and body outside the cyst. Enlarged. (After Davalne.) and these are the regions to which the attention of the inspector should be especially directed. As above stated, the cysts, though variable in size, are ordinarily readily visible to the naked eye ; and in all cases then- nature is easily determined by the microscope. The smallest cysticercus observed by Leuckart in the pig was about y^ of an inch long and -^^ of an inch broad ; but they are generally much larger and may attain a length of three-fourths of an inch. Living specimens of Cysticercus cellulosse have been foimd in pork twenty-nine days after slaughtering — but after fourteen to twenty days of cold storage the parasites are said to be dead. More ob- THE RATION. 215 servations are needed on this subject. Cooking ordinarily kills cysticerci, but the meat must be well done throughout. Exposure to a temperature as low as 125° F. for the period of five minutes is said to destroy the vi- tality of the parasite, and the temperature of well-done meat must always attain this point. Cysticerci are killed by hot, not common, smok- ing, but saltiag does not have this effect. " Measly " pigs are said to salt badly. Old and rusty pork is frequently termed " measly ;" but this term, in the absence of the characteristic cysticerci, is incorrect. Pork contain- ing cysticerci should invariably be rejected as being unfit for consumption by troops. Trichinosis. — The presence of the Trichina spiralis is by no means urfcommon in swine, the proportion being generally considered as about two per cent, in all animals raised in this country — and this fact has served as an excuse for the exclusion of Ameri- j^^j can pork from certain foreign markets. Of all the examinations made by the Massachusetts Board of Health, the pro- portion of trichinous hogs found was 6.3 per cent. Although infection with trichinse is very rare among our soldiers, only one case having been reported during the thirty- one years 1868 to 1898, this immunity should be regarded as due rather to a na- fig. 76.— ufe cycie and intermediate tional dislike of under-done pork than to Hosteo, Trichina spiralis. (After boi- the freedom of swine from this parasite. Several severe epidemics of trichinosis have occurred in the German army, and the symptoms induced by this parasite are so severe that careful inspection of the pork supplies in this respect is of great import- ance. The presence of trichinse cannot be determined in the living animal im- less a bit of muscle be removed from the under part of the tongue' and exam- ined microscopically. In human beings affected with trichinosis, the blood has been found to contain a greatly increased proportion of large, coarsely granulated, eosinophile cells ; but as yet no application of this test has been made to swine. Within the muscles of animals affected with this parasite may be seen tiny, opaque, ovoid cysts, having a length of about .015 inch and a breadth of .006 inch, within which are coiled very small worms, only to be detected with the microscope. These bodies represent the em- bryonic stage of the parasite ; when swallowed, the envelopiag cyst wall is digested and the embryo liberated. The latter develops in the intestinal canal and reaches maturity in five or six days. The mature worm is white and about the thickness of a hair. The female at once begins to procre- ate, giving off from a thousand to fifteen himdred embryos at a brood ; these passing into the system by way of the lymphatics. After penetrat- ing the muscular fibrillae they become encysted, the cyst wall becomiag thickened and finally undergoing calcification; in which condition they appear as opaque, whitish, lens-shaped bodies. Trichinae are observed in the flesh of hogs, cats and rats ; less frequently in certain other animals. The rat and cat are believed frequently to play a part as intermediate hosts in its occurrence in swine. 216 THEOEY AND PEACTICE OF MILITARY HYGIENE. To the naked eye, pork infected with trichinse usually presents nothing characteristic. In certain cases in which the cysts have undergone calcifi- cation they may appear as white dots, and if very numerous may give rise to a distinct grating sensation under the knife. Por the microscopical ex- amination thin strips of muscle should preferably be cut from the tongue, diaphragm, muscles of the jaw and larynx, or the intercostal muscles, since these parts are the ones most liable to harbor the parasite. These strips are pressed firmly between two glass slides and then examined under a magnifying power of forty to sixty diameters. If the meat is very fat it may be treated first with ether or benzine. The muscle may be cleared and the cysts rendered more prominent by inunersing the bit of muscle in a solution of weak potassa, one to eight, for a few minutes ; but if left* in Fig. 74.-1, Trichinae in muscle ; 2, embryo trichinse ; 3, encysted trichinae ; 4, cyat containing seven tri- chlnEB ; 5, trichina in latty tissue ; 6, trichina removed from cyst. (Alter Laveran.) too long the trichinae are destroyed by the alkali. Calcified trichinse may be rendered transparent iby the addition of a drop or so of diluted acetic or hydrochloric acid, when the worm is distinctly seen. Trichinse are not destroyed by the ordinary process of smoking meat ; but hot smoking, ac- cording to Leuckart, does destroy them. Pickling in strong brine is said by Stiles to kill them in about four months, but neither freezing nor the complete decomposition of the meat destroys their vitality. They are readily kiUed by exposure for a few minutes to a temperature capable of coagulating albumin (158° F. ); but when the interior of a piece of pork still retains the fresh red color of uncooked meat, it may be assumed that a temperature sufficiently high to destroy this parasite has not been at- tained. It is by no means easy to raise the temperature in the interior of a large ham sufficiently to destroy with certaiaty the contaiued trichinae, and constant boiliag for several hours should invariably be required. THE RATION. 217 It is scarcely necessary to say that where the presence of trichinae can be positively demonstrated the affected meat should be promptly con- demned. The so-caUed Psorospermia, or Eainey's capsules, must not be mistaken for trichinae, nor indeed with care is error possible. These are smaU, al- most transparent bodies, found in the flesh of oxen, sheep and pigs. They are oval or spindle-shaped, or sometimes one end is pointed and the other rounded, or they are kidney-shaped. The iavesting membrane exhibits delicate markings, caused by a linear arrangement of minute, hair-Kke fibres which are stated to increase in size as the parasite gets older. They are sometimes pointed, and the appearance under a high power (one thou- sand diameters) is as if the investment consisted of very delicate, transpar- ent, conical hairs, terminating in a pointed process. The contents of the cysts consist of granular matter, the granules or particles of which, when mature, are oval and adhere together so as to form indistinct divisions of the entire mass. The length varies from one three-hundredth to one-fourth of an inch. They are usually narrow ; they lie within the sarcolemma, and appear often not to irritate the muscle. In human beings these bodies are not known to produce any ill effects, but their existence should be remembered in searching for trichinae. Bacon. — In the military service the flesh of swine is ordinarily used in the form of bacon or salt pork. The composition of the former, as or- dinarily issued to troops, is as follows : Water, per cent. Protein, per cent. Fat, per cent. Fuel value per pound. Calories. 16.8 9.3 61.8 3,606 For field use no meat can take the place of bacon. It is readily trans- ported, prepared and digested; is appetizing when properly cooked, and possesses a high calorific value in a small bulk. It is much more accept- able than pork, but contains too high a proportion of fats to render its fre- quent issue desirable in hot climates. For such stations, bacon consisting of almost clear fat should not be issued, but a fair proportion of lean should be required. As a general rule, the frirther north the station the greater the proportion of fat which may be allowed. Discrimination should be used by the Subsistence Department in this respect. When very fat the loss in cooking is great ; the soldier when frying his bacon in his in- dividual mess-tin rarely securing the full benefit of the melted fat. Many soldiers prefer to fry their bacon to a crisp, rejecting the grease — in which case only a relatively small proportion of its nutritive substance is utilized. In general, the weight of the sides determines the proportion of fat, and sides weighing from twenty-five to fifty pounds are preferable. The wastage of bacon under natural heat is often considerable, amount- ing at times to as much as twenty or twenty-five per cent. When slop- fed and summer-cured, bacon is said to waste much more rapidly than when corn-fed or winter-cured. Notwithstanding this waste under heat, properly selected bacon should be generally substituted for salt pork at southern posts. Bacon is preferably stored in the crates in which it is 218 THEORY AJ^D PEACTICE OF MILITARY HYGIENE. issued. It has been stored in bins, packed with bulk salt in alternate layers, but the salt appears to cause the separation of the fatty portion from the riad. At southern posts, where bacon becomes very soft and liquescent, it is best packed in charcoal, after wrapping in clean cotton cloths. Poorly cured bacon is soft and watery and will not keep. When cut into, moisture appears in the incision. The only remedy for this condition is a second smoking. When the fat of bacon i's yellow and the taste is strong, the meat is rusty or tainted. When the lean shows brownish or black spots it is not good. Bacon from stag hogs or those fed on mash may have a yellowish appearance and still be fit for use. The Dermestes lardarius or bacon-bug is very destructive to bacon and aU other kinds of dried meat. It is a rapid breeder, and a generation may be developed in six weeks. This insect deposits its eggs on bacon or other dried meats; the larvae being hatched from these and at once beginning their attacks on the flesh. Wlien fuU-fed they change into the chrysalid state and from that iuto the beetle ; the latter being about one-third of an Fig. 78.— Dermestes lardarius : a. larva ; b, pupa ; c, adult beetle— all enlarged. inch long and of a dusky-brown color, except the upper half of the wing cases, which are of a whitish or ashen color. These insects, when iu the larval and chrysalid states, are so concealed in the meat that they cannot be removed from it — ^but upon attaining the beetle state they may be readily removed and destroyed. Affected portions of bacon should be cut away. Where a commissary store-room is overrun with these insects, the room should be cleared out as far as practicable, and sprayed with benzine or subjected to strong fumes of bisulphide of carbon. The latter method is much recommended, as the disagreeable odor of this substance soon disap- pears. Salt Pork. — The chemical composition of salt pork, as issued, is in general as follows : Water, per cent. Protein, per cent. Fat, per cent. Fuel value per pound, Calories. 16.2 16.2 66.3 2,733 THE RATION. 219 Salt pork is by no means a popular component of the ration. It is rarely used in garrison except when cdfcked as an adjunct to beans or vege- tables, and ia the field it is entirely supplanted by bacon. So many and so general were the complaints made, a decade ago, against salt pork as a food for the soldier, particularly from southern stations, that the matter received special consideration in the report of the surgeon general for 1889, and strong evidence was adduced against its further issue to troops. It was shown not to be relished by the men and to be rarely used, and was reported as being ''repulsive to taste and digestion." Pormerly it formed three-twentieths of the meat ration; and in the department of Texas it was reported by the commandiug general that, for the year 1885, one-half the issue of pork was turned back to the commissary and its money value expended for other foods, it thus being utilised merely as a means of exchange. This dislike of pork, however, was not shared by the colored troops, and in a sanitary report from Fort Duncan, Texas, in 1880, it was stated that three colored companies, with an aggregate strength of one hundred and forty-one, saved only three hundred and fifty-seven pounds of pork — and one of these companies made no saving in this re- spect ; while in a company of white troops at the same post, with an aver- age strength of fifty-eight men, no less than three thousand pounds were saved during the same period. In the entire department of Texas it was found that the white troops saved and sold proportionately twice as much pork as did the negro soldiers. It would undoubtedly be of advantage if pork were replaced in the ration by an allowance of cheese, leaving the small amount of pork which might be desired for cooking purposes to be purchased from the commissary as required. Corn-fed pork is the best quality of pork found in the general market. It can be distinguished from mash, slop or swill-fed pork by its pearly appearance, and by its retaining the dent of the finger on pressure. Mash- fed pork has a blue tinge, is spongy and is elastic to the touch. Winter- killed pork is much better than pork killed in warm weather. If it freezes before thoroughly cured, however, it will spoil when thawed out; as freez- ing suspends the pickling process. Pork should be subject to frequent inspection. If the meat is a little turned it may at times be saved by rubbing in salt and rebrining. The barrels should be kept on the side, rolled at weekly intervals and carefully protected from the sun. Pork is never safe if there is not a considerable quantity of undissolved salt in the barrel; and the loss of brine by evaporation must be promptly made good. If brine be added it should be of sufficient density to float an egg. Horse Meat. — The flesh of the horse, though not employed for the subsistence of troops in time of peace, is capable of rendering excellent ser- vice during campaign. It was much used by the French during the sieges of Metz and Paris in the Franco-Prussian War, was lately employed during the Anglo-Boer War, and, together with mule meat, has not infrequently been of necessity utilized by our own troops in expeditions against hostile Indians. Horse meat is palatable and wholesome, and where the meat ration is at all insufficient the flesh of animals kOled in action should cer- tainly be utilized as food. The flesh of the horse is said to contain about ten per cent, more nitrogen than good beef; a quality which should make it especially valuable in connection with the shortage of food and the 220 THEOEY AND PEACTICE OF MILITAEY HYGIENE. arduous labors incident to hard fighting. Horse meat is now regarded as a staple article of diet among the poorer classes of Europe, Laveran stating that in 1892 no less than twenty thousand horses were slaughtered for food iu Paris alone; and in the western part of our own country it is said that several companies are engaged in canning the flesh of the half -wild horses of the plains for European consumption. In view of its common u^e abroad it has recently been proposed, from motives of economy, to in- clude horse flesh in the meat ration of several foreign armies. Its issue iu our own service, however, would never be countenanced except as a meas- ure of urgent necessity. Horse meat can be detected by the horse having eighteen pairs of ribs, while the ox has but thirteen pairs ; the tongue of the horse is smooth at the tip and base of blade, while the tongue of the ox is rough. Ordinarily, however, a fore-quarter with more than the number of ribs possessed by the ox would not be presented ; hence the points to be chiefly relied upon are the darker color and coarser fibre of the flesh of the horse, the yellow, oily fat, the greater size of the bones and their oUy marrow, the peculiar odor and somewhat unpleasant taste of the fat. The flesh of the horse ap- pears to be lesis liable to transmit disease than either pork or bacon, since this animal is not liable to trichinosis, is relatively insusceptible to tuber- culosis and is not known to contain parasites which can be transmitted to man. The horse is frequently affected with glanders, but the flesh of glandered animals does not appear necessarily to produce injurious effects, if thoroughly cooked, when eaten as food. Viry quotes an instance in which three hundred glandered horses were eaten without injury; and in 1870, during the siege of Paris, large quantities of flesh from horses with farcy and glanders were eaten without producing ill effects. There can be no doubt that glandered flesh, however, if insufficiently cooked, is capable of transmitting this disease to the consumer. Slaughter-Houses. — In addition to the examination of the animal from which the meat is derived, and of the meat itself, it may frequently devolve upon the sanitary officer to supervise the method of slaughtering and cutting up of the carcass, and insure that all the steps are carried out in a cleanly manner and that the meat is not unnecessarily contaminated by carelessness or filthy surroundings. Slaughter-houses are natmally cen- tres of disease, and the more unsanitary the condition of the premises the more dangerous they become to health. It not infrequently happens that little care is bestowed upon the policing of such an establishment and its vicinity, which, in the nature of things, are befouled with urine, droppings, blood and decomposing offal. This is a matter requiring the constant at- tention of the supervising officer, and every effort should be made to pro- mote cleanliness and remove unsanitary conditions. Frequently slaughter- houses are located on the banks of streams, which, lower in t'tieii- course, are sources of water supply ; and in many instances the offal is thrown out to be eaten by hogs kept for the purpose, or by rats and prowling dogs. This practice is extremely dangerous, for even if the abattoir be small the number of animals slaughtered therein in the course of a year may be considerable. Among the hogs slaughtered, a certain proportion are sure to be affected with trichinosis, and when the offal of a trichinous hog is fed to swine the latter cannot escape infection with trichinse. But THE RATION. 221 this is not all ; for rats act as transmitters of trichinae to hogs, and slaugh- ter-houses are usually overrun with these vermin. Where these feed on the offal of trichinous animals they likewise acquire trichinosis ; Stiles find- ing fifty-five per cent, of rats killed in slaughter-houses, meat shops and packing-houses to be so diseased. The affected rats, after death, are them- selves not infrequently eaten by hogs — and further, if the abattoir be burned or abandoned, they scatter in all directions for the purpose of ob- taining food and thus greatly increase the chances of the dissemination of the disease among swine kept in the vicinity. Hence the great necessity for keeping down the rats by the use of traps, cats, ferrets and poison. Tuberculosis is also transmitted by flesh, and swine fed on the offal of tuberculous animals themselves become affected, and may, when slaugh- tered, give rise to the disease in man. Dogs also are attracted to slaugh- ter-houses ; and through eating the discarded organs they infect themselves with several kinds of parasites, among them the echinococcus disease, the thin-neck bladder worm, the gid bladder worm and the tongue worm. The first named parasite is extremely dangerous to man — the latter affect animals. The dog, after eating flesh containing parasites, proves a con- genial host for the development of the mature tapeworms, and naturally deposits the eggs, with the excreta, in all directions and under conditions which favor their entrance by the medium of water and herbage into hosts suitable for their development. It is obvious that dogs should be pre- vented from having access to abattoirs or their animal refuse. It is needless to enumerate all the diseases which might centre at a slaughter-house; but anthrax, tuberculosis, hog cholera and swine plague may be mentioned. As the yards and buildings will often harbor the specific organisms of these and other diseases, it should be a rule that an animal once admitted to a slaughter-house should not leave it alive. The flesh of diseased animals should be burned, not buried ; since in such a case the carcasses may become food for dogs, rats and burrowing animals. Further, on Indian reservations or in the tropics, they may be subse- quently disraterred and used as food by the natives. In construction, slaughter-houses should be solidly buUt, preferably of brick or stone, and should have cemented floors throughout. They should be well drained and scrupulously maiatained ia a good sanitary condition. In the transportation of meat the strictest cleanliness of hands and clothing should be required of those in charge of its conveyance from place to place, and of the wrappers, receptacles or vehicles in which it is so conveyed. During transportation to the place of issue the meat should be well exposed to air ; imder no circumstances should it be wrapped in rubber sheeting, as is sometimes done, but the air should have access to it at aU times. When kept in store, without refrigeration, the meat should be hung up in as cool a place as possible, the pieces being not too close to the wall or to each other, well protected from dust, sun and flies, and, if possible, in a free current of air. PRESERVATION OF MEAT. The necessities of the military service obviously require that meat should frequently be consumed at considerable distances from the places of production and slaughter; and hence its preservation, by physical and 222 THEOEY AND PRACTICE OF MILITAEY HYGIENE. chemical means, has been an object of constant study on the part of those who have the subsistence of troops at heart. The artificial refrigeration of meat, a process only of comparatively recent development, has done much toward satisfactorily solving this vexed problem. The following methods have been employed for the preservation of meat. Method of Slaughter. — It has been demonstrated that meat killed in the Jewish manner wiU keep one or two days longer in summer than meat killed the ordinary way, since the more thoroughly the blood is removed the better the meat keeps. In the Jewish or " kosher " method the animal is hauled ilp by the hind legs and the throat is rapidly cut without pre- vious stunntag; the vessels retain their contractility and convulsions take place, which stiU further help to squeeze aU blood from the body. If the animal is first stunned the bleeding is imperfect and considerable blood is left in the hind-quarters. The objection to this method of kill- ing is the unnecessary cruelty attaching to it. The same result is reached in a new process by which the keeping qualities of the meat are said to be markedly enhanced. In this method, after previous stunning and bleed- ing, the large blood-vessels are washed out with a weak, sterilized salt solution ; the irrigation being continued for some minutes until the escap- ing fluid is only faintly colored. The animal is hung up by the hind legs during the operation, and the irrigating trocars are plimged iato the femoral arteries. Where refrigeration is not available, and it is desired to keep meat several days during warm weather, this method of preservation has much to commend it, being simple of execution and entirely avoiding the use of chemical preservatives. Refrigerated and Frozen Meat. — The preservation of meat by cold, and its transportation in the chiUed or frozen state over long distances to the point of issue, is now a common procedure in the military service. In France, Germany and other countries, military cold-storage establish- ments, fully provisioned against emergency, are maintained at strategic points from which distribution can be readily accomplished. Viry states that one-fifth of all the cold-storage establishments in Germany are exclu- sively employed in the military service. In the United States army no need for such establishments has existed, through the comparatively small numbers of the regular array, its dissemination in small garrisons over a wide area, the readiness with which supplies could be obtained by reason of excellent transportation facilities, the existence of large, centrally located packing-houses belonging to private corporations, and finally, the geograph- ical situation of this country, through which invasion by foreign forces is rendered impossible. In the tropical possessions, however, no such condi- tions prevail, and in Cuba, Porto Eico and the Philippines the establish- ment of cold-storage facilities has been found essential. In the Philip- pines the troops were at first supplied du-ect from the ships bringing meat from the United States and Australia, but recently a refrigerating plant has been established at Manila, having a capacity of five thousand beeves, eight thousand sheep and other perishable articles in like proportion. As delivered to troops, refrigerated beef is almost invariably of excellent quality and in prime condition. Little difficulty has been experienced in preserving the meat imtD. required for use, although in several instances in our service the refrigerating apparatus on board transports has broken THE EATION. 223 down during the voyage and all perishable articles lost in consequence. Kefrigerated beef, as shipped to troops in the tropics, is far superior to native grown meat, which is usually deficient in fat and is tough and stringy from the fact that it must be used a few hours after killing to pre- vent spoiling, even though rigor mortis be still present. Meat should be refrigerated rather than frozen if it is to be issued at no great distance from the point of refrigeration. Where transportation over considerable distances is required for the supply of troops, actual congelation becomes advisable in the prevention of putrefaction. As an additional precaution against contamination and spoUing, the quarters shoiild be sewed in clean, steril- ized cotton cloths before shipping. Eefrigerated beef differs slightly in appearance from fresh, having a dead color and lacking the lustre charac- teristic of good fresh meat. The lean is somewhat pale in hue and more of a brick-red color than the bright, rich red of recently kdled beef. The fat is pale pink instead of white, due to the juice of the lean soaking into the fat. A general pinkish tinge extends over the whole of the carcass and the gristle of the joints is pinkish instead of bluish in color. The shanks are bruised and discolored owing to the method of hanging up the quarters. Sometimes the shanks are much lacerated, and such injured portions, besides being objectionable in appearance, readily become tainted. The carcass itself is cold to the touch, stiff and moist. On removing the cloth in which the quarter is wrapped for transportation a slightly unpleas- ant odor is sometimes discernible ; but care should be taken not to reject such meat without further examination, since the smell may be merely a smrface one caused by the cloth. When this is removed the quarters should invariably be cut into, when if any taint exists it wUl be readily detected. Meat in the frozen state is readily recognized. In the thawed or semi- thawed condition the outside has a wet, water-logged appearance, and there is considerable oozing and dripping of a watery liquid from the carcass. Should it have been kept so long a time as to have lost its outward moist- ure it can be recognized by a generally dull, dirty appearance, and on a fresh section being made the watery condition is at once apparent. This dripping and infiltration is due to the rupture of the cells by freezing and the subsequent escape of their liquid contents, to the no slight deterioration of quality. The flesh has a uniform pink appearance, owing to diffusion of the coloring matter in the blood. The fat, however, is unstained and is of a tallowy white color. The outside of the meat is dull and lacking in lustre. It is said that in the Philippines frozen quarters of beef have been transported to troops on the firing line fifty miles from the cold-storage establishment, and have been kept free from taint for as much as three days without further refrigeration, even in a tropical temperature. Frozen beef is not accepted in the British army, although frozen mut- ton is regarded as satisfactory. The reason for this discrimination is that the carcasses of sheep are frozen whole, while beef is cut into a consider- able number of parts, and on thawing the loss of nutritive matter from the flowing of liquid from the cut surfaces is much greater. Mutton being naturally drier than beef it is said to suffer less deterioration in the freez- ing process. The committee appointed to investigate the dietary of the 224 THEOEY AND PEACTICE OF MILITAEY HYGIENE. British soldier recommended that when frozen meat is issued an extra allowance of ten per cent should be added " on account of the waste that occurs in the process of cooking it." Since frozen meat iS now much used in our service it would seem as if this matter deserved attention. Frozen meat, after thawing, undergoes decomposition much more read- ily than refrigerated meat, through its infiltration with serous fluid. . To the mechanical disorganization of the tissues from rupture of the muscle cells is thus added the diffusion through the meat of a fluid which fur- nishes an admirable culture medium for the development of the micro- organisms of putrefaction. In the inspection of frozen or refrigerated meat it should be cut through iu the thickest part, since when the meat is frozen while still warm, the outside forms a hard protective casing behind which putrefaction may be possible. It has recently been stated in a sani- tary journal that meat long kept in cold storage undergoes a deterioration of intangible character. Such meat is said ultimately to lose in flavor and be poorly assimilated. It is also stated that those who eat meat long pre- served in cold storage are particularly prone to diarrhcsa. The moral of this is to avoid keeping meat in cold storage any great length of time, and to make contracts for small but frequent consignments of the freshly killed article. The apparatus for the production and maintenance of artificial refriger- ation, at permanent posts, is discussed in a subsequent section. To in- sure the better keeping of meat in the field, an excavated cellar may be made in connection with the camp kitchen, roofed with logs, brush, leaves and a heavy covering of earth, and having a passageway communicating with a small tent. Excellent surface drainage must be provided for the removal of storm water ; while, if the ground water be high, subsoil drain- age by trenches somewhat deeper than the cellar, and carried to a lower level, should be instituted. These trenches should be partially iilled with large stones, loosely placed ; or poles be laid horizontally to carry off the water. Where ice is available in the field, excellent ice chests may be made of packing boxes sunk in the ground one inside the other, and hav- ing holes bored in the bottom to allow the escape of water. A tight lid is provided for each box, and the whole shielded from the sun. In garri- son, a more elaborate commercial form of refrigerator wOl usually be em- ployed. These should be well lined with zinc throughout. Some refrig- erators now supplied by the Quartermaster's Department are wooden throughout, absorb odors and organic matter and are incapable of proper cleansing. The sanitary condition of such refrigerators soon becomes very bad, and the slight additional cost of better models should not be allowed to stand in the way of their issue. Preservation by Heat. — Directly opposed to the method of refriger- ation is one consisting in exposing the meat to a high temperature for a few minutes ; thus destroying the bacteria and coagulating the albumen in the surface layers and hermetically sealing the interior. This process is obviously not applicable except on a small scale, and is of value for limited periods only. In hot weather, in the absence of ice, the use of this method of preservation will frequently be temporarily of advantage to troops in the field. Desiccation. — ^Drying or " jerking " meat in the open air is a common THE EATION. 225 metliod of preservation among the Indians and frontiersmen of the west, where the dry air prevents putrefaction. "Jerked" meat has not been infrequently employed by United States troops duriag campaign against hostile Indians, the flesh of the game killed while on compaign being often preserved for future use ia this manner. It appears to have given satis- faction, and is very palatable when made up in soup or stews. It is ob- vious that this method of preparation is possible only under suitable at- mospheric conditions. This process is artificially imitated in the dried beef of commerce; but the latter is also treated with salt and is too strong- ly impregnated with saline material to be of utility for the military service. Pemmican — dried meat pounded to a powder and mixed with fat, sugar and raisins — is an excellent food, formerly much used ia the far ISTorthwest. It was employed in the military exploring expedition ia the Arctic led by Greeley, and has also been used by military exploriug expeditions ia Alas- ka. Its composition, concentration, keeping qualities and portability give it a high place among the preserved meats. Smoking. — This is a method of preservation which is usually employed — as in the preparation of bacon — in connection with salting and drying. The best woods for smoking are hickory and rock maple, the preservation being due to the absorption of pyroUgneous acid and creosote from the smoke generated in the slow combustion of the wood fuel. Canning. — ^Next to refrigeration, the canning of meat is pre-eminent- ly the best method of its preservation ; but it may be laid down as a gen- eral rule that preserved meat should be regarded purely as a variety of diet and used rarely. For the military service, the compactness, portability and keeping qualities of canned meat render it of especial value. Canned fresh beef, known as "roast" beef, has long been used success- fully as a component of the United States army travel ration, but was sub- jected to much unfavorable criticism when used by troops in 'Cuba and Porto Kico during the war with Spain. This criticism, however, was due not so much to the undesirable character of the food itself as to the faq|; that it was, from force of circumstances, usually eaten direct from the can, and its issue was contiaued for so long a period that the very monotony of the diet produced a marked repugnance to this meat on the part of troops. Where issued only occasionally, and where proper facilities for making it into hash or stews are furnished, canned meat may be regarded as an acceptable article of food for troops. It is much used and lilied in foreign armies — notably the French army — in which stewing is the usual method of preparing the meat ration. It is quite unsuited for use when eaten direct from the tin, since the meat is comparatively tasteless and stringy and the fat is collected in an unappetizing cake at the top of the can. Canned beef contains no bone — a great saving to the soldier — and much of the water and fat is removed by the processes to which it is sub- jected. Its fuel value is fully equal to fresh beef, pound for pound, while the proportion of nitrogenous matter is much greater. It should, therefore, prove satisfactory — temporarily at least — for nutritive purposes in the field; for which use its keeping qualities, and the fact that it may in emergency be eaten without cooking, render it particularly applicable. The influence of canning on the composition of beef is shown by the foUowiag analysis, hitherto unpublished, made by Bigelow for the Department of Agriculturej, 15 226 THEOEY AND PRACTICE OF MILITAEY HYGIENE. on three hundred and fifty-eight pounds of fresh beef which was converted under his observation into two hundred and thirty-five pounds of canned beef. Fresh beef, weight and composition in Pounds Avoirdupois. Extracted by boiling. Pounds Avoirdupois. Added in canning. Pounds Avoirdupois. Calculated composition of canned meat, Pounds Avoirdupois. Composition of resulting canned meat, as determined by analysis. Pounds Avoirdupois. Water 354.8 59.3 49.7 4.9 4.7 3.9 35.4 8.4 .1 1.2 132.1 0.1 .1 .7 12.3 .7 .1 14.1 .1 1.6 ' ' '.'3 .2 59.3 54.6 4.6 3.1 "3.9 146.8 Proteids, total " coagulated. " globulins . . Proteoses ) Peptones [ Gelatin ) Meat bases 58.5 53.3 6.3 2.7 Pat 23.2 Ash 3.1 Sodium chloride Undetermined .4 1.7 Totals 358.0 .... .... 235.0 The chemical composition of canned roast and boiled beef, as given by Atwater and Bryant, is as follows : Water, per cent. Protein, per cent. Fat, per cent. Fuel value per pound. Calories. Canned roast beef 58.9 51.8 35.9 35.5 14.8 33.5 1,105 1,425 Canned boiled beef ... It is readily seen from the above tables that the popular statement tjiat the " good " is all removed from canned beef is quite without founda- tion in fact ; the latter contains, weight for weight, a much greater amount of nitrogenous material, while the proportion of fat in the fresh and canned meat is almost exactly the same — although there is an actual loss, in this respect, of about one-third. It is true that a certaia proportion of the ex- tractives, which give flavor to the meat, are unavoidably removed in boil- ing, but of these, according to analyses made by the Department of Agri- culture, not more than one-sixth to one-third, varying with the special method of processing, is extracted in canniag. These substances, more- over, have no positive nutritive value but may be regarded merely as stimulants. Of the total proteid iu canned beef, it is stated by Notter and Firth that not. more than ten per cent, was found by them to be indi- gestible. The meat used for canning is ordinarily of good quality, although the less valuable portions of the animal, as the chuck and rib trimmings, are commonly utilized for this purpose. ■ It is claimed, however, that par- tially spoiled meat is sometimes used for this purpose by unscrupulous dealers. In the inquiry after the war with Spain, one ofiicer testified to finding dead maggots in a can on opening it. On its preparation, the beef is first placed in water and maintained at a temperature of 95° 0. until well cooked. It is then removed, trimmed THE EATION. 227 and placed in cans, a little gelatin being added to bind the meat together. The cans are then sealed and either submerged in boiling brine or placed in super-heated steam at 125° C. The contained steam is aUowed to es- cape through a puncture made in the cap of the can, which is immediately afterward closed with solder. The meat being sealed up while hot, any portion of the enclosed space is a partial vacuum ; consequently a good tin of meat will almost invari- ably present a concave appearance on its 'external surfaces through the pressure of the atmosphere. When a tin is bulged it is sure to be bad — unless it be frozen — and should be rejected. The bulging is due to the gen- eration of gas in the process of decomposition of the meat inside. The ends of such cans, if pressed, give out a rattling sound and resume their convex shape on removal of the pressure. Freezing causes a bulging of the ends of cans without injuring their contents. The ends, after the con- tents of the can have been thawed, return to their former shape; but a number of freezings and thawings may so change the contents of the tin that the ends wOl not, on removal of pressure, remain in their original shape. The process of canning articles of food involves the making and solder- ing up of two punctured holes in the top of each can, and these have no bad significance. The presence, however, of three such holes is an evi- dence that the can had been imperfectly processed, and that to remedy this defect it was re-heated, the gas of fermentation allowed to escape, and the hole punctured for this purpose again sealed up. The contents of re-heated cans are more likely to be of inferior quality, or subsequently to undergo putrefactive changes, than cans properly processed in the first instance. Owing to the objections to re-heated cans, the packers are careful to make the third puncture as inconspicuous as possible; and frequently endeavor to conceal it entirely by making it on the side of the can, near the top, and pasting the label over it. By ruiming the finger aboimd the rim of a can it is easily determined whether a third hole has been made, by the presence or absence of a lump of solder. Sometimes newly packed cans are so much swollen that re-heating is not sufficient. In such cases the cans are opened, the contents sorted over and the sound parts packed into cans, which are then subjected to the same process as in the original can- ning. Ee-processed cans of this character have the same appearance as regularly packed cans, and their defective quality can be determined only by opening and examining their contents, which will present an over- cooked appearance. First-class canned goods have both the name of the factory and that of the wholesale house through which they are sold upon their labels. Doubtful goods have a fictitious factory name, and no deal- er's name. These are easily avoided in peace — but under the pressure of war, supplies of this character are apt to deteriorate and must be critically watched. Canned meats, when properly stored, should theoretically retain their good qualities indefinitely in any climate. A certain gradual deterioration appears, however, to occur, and Morache states that in cans of meat a change, similar to the formation of adipocere, sometimes occvu'S. Viry states that putrefactive changes may take place without the formation of any gases. He recommends that canned meat having a fishy or putrefac- 228 THEOEY AND PEACTICE OF MILITARY HYGIENE. tive odor, in which the fat is liquefied or has lost its transparency, or when the meat is soft or discolored, should be rejected. He states that these conditions may occur ia canned meats presentiag no outward signs of bad quality, and remarks that a considerable number of cases of illness among the French troops has demonstrated the danger of using meat of this character. Coustan mentions ten severe outbreaks of ptomaine poisoniug, occur- ring from the use of canned meats, as having been noted in the French army. Barker has recently observed severe poisoning in twenty-four per- sons following the use of canned beef. He states that this meat presented no unusual appearance other than that it was less firm than is ordinarily the case, and the jeUy was slightly oily. The meat had no odor, and its taste was not unpleasant except to a single individual of those who par- took of it. Meat contained in pierced tins wiU, of course, putrefy very quickly, and therefore all cans showing holes made by nails, rust, crush- ing or other means should be rejected. In an inspection recently made in Cuba, many thousand cans of meat, which had been carried in the holds of transports and had come into contact with salt water, were found to have rusted through and their contents undergone decomposition. It is important that cans of meat should not be opened except as required for immediate use, since canned meat appears to undergo putrefactive changes more quickly than fresh meat. The quality of canned roast or boiled beef is determined by its appear- ance, which should be bright, lively and well colored; by its flavor, which should be pleasant, and by its freedom from gristle, sinew and fascia. A due proportion of fat should be present. This is usually collected with the gelatin at the top of the can. Packers endeavor to prevent the solidification of this fat in cakes, during the process of cooling, by frequent turning of the cans — but their efforts are only partially successful. Canned beef con- tains ordinarily from fifty to sixty per cent, of moisture. The transporta- tion of this amount of innutritions matter in the field ration is certainly undesirable, but it is admitted by the canners that the meat is stringy, uninviting and flavorless unless this proportion of water be allowed to remain. It is not disputed that canned food frequently contains tin, which has been dissolved from the tin plate by the action of acids or other constitu- ents of the food, or which have been introduced through the careless use of stannous chloride, a constituent of some of the soldering fluids used in sealing cans. But the quantity of tin is usually very small, varying from a few hundredths of a grain to one grain per poimd — rarely approaching, however, the higher figure. These amounts are not likely to give rise to acute poisoning. Usually canned fruits and vegetables, from their con- tained acids, are more liable to dissolve tin than is meat so preserved. Blyth states that he found in some samples of canned fruit as much as 14.3 grains of stannous chloride per pound, and that the average amount of all examined was 5.^ grains per pound. In some cases the juice had a metallic taste. With such quantities of tin, in a form easily absorbed into the system, the possibility of acute poisoning must be admitted. But tin poisoning, from the use of canned foods, is not greatly to be feared. A quantity of tin salt sufficient to cause acute poisoning would probably be THE EATION. 229 recognized by the taste, and food so contaminated would be rejected as un- palatable. Used in the manner in which canned food should be employed in the military service, the possibility of chronic tin poisoning should also not exist. In speaking of a number of cans of beef examined by him for the Department of Agriculture, Wiley remarks as follows : " On opening the cans it was found in many instances that the tins on the inside were discolored, and it was first considered that actual erosion had taken place. A careful microscopic examination of the surface, how- ever, showed that this assumption was an error. In no case was the sur- face of the tin found to be eroded, and the discolorations were due doubtless to the natural effect of the meats upon the tin surface." In general, the tin used in making cans should be of the best quality and the solder should be carefully applied to the outside of the cans only, so as to prevent it from coming into contact with the contents. It is important that animals to be used for canning purposes should be inspected on the hoof, since if the animal is sick and the flesh contains bacteria or toxines, the heat of processing may not destroy the toxiaes or spores of the bacteria even though the micro-organisms themselves do not survive. Canned corned beef is prepared in almost exactly the same manner as canned roast or boiled meat, the flesh having previously lain in pickle for fifteen to twenty days. It is the usual meat component of the travel ra- tion, for which purpose it has given entire satisfaction. Its percentage chemical composition is as follows : Water, per cent. Protein, per cent. Fat, per cent. Fuel value per pound, Calories. Oanned corned beef 51.8 36.3 18.7 1,280 Canned corned beef is very salty and soon becomes distasteful to troops. Its employment, except for very brief periods only, should be condemned. Meat is sometimes preserved in tin cases by partly excluding air and destroying the oxygen of the remaining part with sodium sulphide. In another process the air is removed from the packed cans and nitrogen, with a little sulphur dioxide, substituted. Salting. — Corning is treating raw beef or pork to a pickle, usually composed in the proportion of two gallons of water, four pounds of salt, one and one-half pounds of brown sugar, one and one-half ounces of saltpetre and one-half ounce of saleratus. The meat, cut into pieces of about eight pounds each, is put in the brine under a weight. After an immersion of eight or ten days it is ready for use. If the meat is pickled directly from the block, the bloody brine should be renewed every three or four days until all the blood has soaked out. In corned beef the extractives are in great part removed by the brine, while the albumen is hardened and the meat thus rendered tough and insipid. The process of curing appears somewhat to impair digestibility and the meat is much too salty for contin- ued use. In the expedition to Porto Eico, when a deficiency of transpor- tation rendered it necessary to use caimed corned beef for a number of days, the men were said to have suffered greatly from thirst and to have 230 THEORY AND PEACTICE OP MILITARY HYGIENE. been affected with a condition of the mouth similar to that resulting from mild mercurial salivation. Salt beef is good only when new; after a year it becomes drj' and tough, especially if made of fresh beef of inferior quality. The determina- tion of the quality of corned meat is by no means easy and the test of cooking must often be employed. When the salting is badly done signs of putrefaction can often be detected. The meat is paler than it should be, is often sKghtly greenish in appearance and may have a peculiar odor. If the meat has become tainted before briniag, no salting will remove its softness and it may present the odor of putrefaction. If the meat is old, its hardness, toughness and shrivelliag will be noted. The use of inferior portions for salting can be determined by inspection of the meat after re- moval from the brine. It should be remembered that brine is sometimes poisonous. This occurs in cases in which the brine has been used several times ; a large quantity of animal substance passes into it and appears to decompose. The special poisonous agent has not been isolated, but prob- ably is a ptomaine. Meat from a pig slaughtered on account of sickness, which had been pickled in strong brine for four days and smoked for three more, was foimd by Glucksmann to have induced fatal poisoning. Proteus vulgaris was found in the meat and stomach contents, and when injected into animals proved very virulent. The following is the average chemical composition of corned beef: Water, per cent. Protein, per cent. Fat, per cent. Fuel value per pound. Calories. 49.2 14.3 33.8 1,371 The subject of salt pork has already been discussed. Chemical Preservatives. — Of these, borax and boric acid are now al- most generally employed for the preservation of fresh, raw meat, since they are effective and cheap as well as odorless and their taste is easily lost or disguised when mixed with food. Boric acid is usually preferred by butchers to borax, as the latter is considered to bleach the meat. Boric acid enters largely into the secret powders used for meat preservation, the accessory preservatives being variously salt, saltpetre, sodium sulphite and other substances. Ordinarily the surface of the meat is lightly dusted over with the boric acid, from ten to fifteen grains per pound being usually employed. In the preservation of sausage meat it is said that four ounces are generally used to each one hundred pounds of meat. Wlien large joints are to be treated, it is customary to cut the meat into comparatively small pieces before applying the boric acid, since internal putrefaction fre- quently occurs in very large pieces of meat and extends from the bone outward. The meat treated with these substances remains in a fresh state for double the usual time and retains its normal qualities and nutritive value. For the sanitarian the question of chief importance has reference to the possible effects of the continued or frequent use of these preservatives upon the health of consumers. In general, it cannot be said that the influence of borax or boric acid, in this respect, is unfavorable when taken in mod- THE RATION. 231 erate quantities. Chittenden fouad no interference with the processes of digestion following the use of borax, and De Cyon observed no disturb- ance of the general nutrition of dogs when as much as 12 gm. of this substance, added to meat, was used daily — this being ten times the amount which would ordinarily be taken in on preserved meat by human beings. The same writer found that when borax was given in sufficient quantity to produce any effect its action was similar to that of common salt, tending to increase proteid decomposition. Boric acid, in doses up to 3 gm. per day, appears to be without influence upon either pro- teid metabolism or the general processes of nutrition. Many general statements have been made in condemnation of borax and boric acid pre- servatives, especially during the recent war with Spain. It is noteworthy, however, that these statements were purely matters of opinion and were not founded on personal observation of any ill effects directly traceable to the use of these substances, and it may probably be accepted that, in the quantities in which they might be taken into the system with food preserved by theii- agency, they exert no harmful influence upon the organism. This lack of toxicity, however, does not necessarily render the use of the borax compounds desirable for the military service ; and this is particularly the case since in artificial refrigeration there is available a far more prefer- able method of preserving fresh meat, and one which is not open to criti- cism through the use of chemical substances. The determination of borax or boric acid in meat is extremely simple, requiring no special apparatus for its accomplishment. A portion of the suspected meat is cut up, boiled in a small amount of water and the latter filtered. A small amoimt of hydrochloric acid is then added to the filtrate, the best proportion being about one part of strong acid to fifteen parts of the solution. A greater amount of the acid interferes with the reaction. A strip of turmeric- paper is then dipped in the acidified solution and al- lowed to dry, becoming a bright cherry red. After the paper is dried a drop of ammonium or sodium hydrate is added ; when, if boric acid be present, the color of the wet paper changes to dark green ; or if boric acid be present in large quantity, to a dull black. If no boric acid be present the addition of the alkali produces a light brown tint, but the play of colors — ^cherry red to green — is characteristic of boric acid. The use of salicylic acid forms the basis of several methods of preser- vation ; this substance haviag a marked effect in restraroing putrefactive processes. A method successfully employed in the Italian army, as far as the preservation of meat was concerned, consisted in covering fresh meat with a coating of salicylated grease, the whole then being packed in kegs or baiTcls. Fresh meat so treated was found capable of being preserved about two months without apparent alteration. The salicylated grease was readily removed and was used over again for a number of times. It is understood that this method was not long used. SaMcylic acid is a drug' possessed of marked caustic properties when used in strength, and is capable of inducing severe toxic symptoms if taken continuously or in considerable doses. Its use for the preservation of meat intended for troops is unjustifiable. The presence of salicylic acid or the salicylates in suspected meat is readily determined by washing the surface of the meat with water, and adding a few drops of tincture of the chloride 232 THEOEY AND PRACTICE OE MILITAKY HYGIENE. of iron to a test-tubeful of the washings. If salicylic acid or the salicy- lates be present a deep purple color is developed, varying in intensity with the amount of these substances. This test is delicate enough to de- termine the presence of one part in the million of the solution. A process which has been considerably employed in the past for the preservation of meat consists in its exposure, for a number of hours, to the fumes of sulphur dioxide. This process is uncertain in its results. It is believed not to interfere with the digestibility of meat ; but when thor- oughly carried out the latter acquires a somewhat bitter taste and a sour, putrid odor. This method is now largely abandoned. It is said that a much-criticised quarter of meat carried on a transport to Santiago, during the war with Spain, for trial as to its keeping qualities, had been treated with sulphur dioxide. Formaldehyde has quite recently been adopted as a food preservative and is now much used — ^though more especially to add to the keeping qualities of milk than of meat. In the proportion of one to fifty thousand, as has been shown by Eideal and Fullerton, formaldehyde, employed in watery solution, is an effective preservative of millc for twenty-four hours. In this strength, even during extended periods of use, this substance appears to have no injurious effect upon the consumer. Meat has been preserved by formaldehyde by spraying, or wrapping it in cloths saturated with a solution of no great strength. When pre- served in this manner meat will remain free from taint for a number of days. Formaldehyde, however, combines with albuminous material to form a new compound, practically insoluble and highly indigestible. When permitted to come in contact with meat it thus forms a protective surface coating, which, besides possessing directly antiseptic and germi- cidal properties, mechanically hinders invasion by the bacteria of putre- faction. Meat treated in this way, however, frequently acquires a dis- agreeable odor, and the appearance of its outer layers is much changed. In the quantity in which formaldehyde could be taken in by the individual with meat preserved by this agent, it may fairly be presumed that no di- rectly toxic effects might be expected. Interference with the digestive processes might fairly be anticipated, unless the outer layers of the meat were cut away and rejected. It may be concluded that for the military service the preservation of meat by formaldehyde is quite inadvisable, and from the chemical changes produced would readily be recognized. Leys states that formaldehyde may be detected by adding together 25 c.c. of the suspected fluid, 10 c.c. of a colorless solution of phloroglucin (1 gm. in 1 liter) and from 5 to 10 c.c. of a weak potash solution, shaking in a test tube. If formaldehyde is present a red color is produced, which dis- appears after a few minutes. Other Methods. — Efforts have been made to preserve meat by vari- ously coating it with fat, glucose, gelatin and glycerin. The application of charcoal or sugar to the exterior of meat is said by WoodhuU to increase greatly its keeping qualities, and the same writer suggests the rubbing of meat with black gunpowder for the same purpose. It is obvious that such methods of preservation can have no practical value for the military service. THE EATION. 233 GEIfEBAL PRINCIPLES INVOLVED IN THE COOKING OF MEAT. By cooking, meat is rendered more pleasing to the eye, acceptable to the palate and digestible by the stomach. Before cooking, meat is tough and stringy, but when cooked the muscular fibres are given firmness from the coaguktion of their albumen, and the connective tissue which biads the fibres together is softened into a gelatinous condition especially favor- able to the action of the digestive juices. If meat is so tough as to resist the softening action of cooking, it may be made tender, before putting on the fire, by macerating in weak vinegar or cutting into thin slices and pounding across the cut ends until the fibres are broken. From a sanitary standpoint, the cooking of flesh has a special value, since, when properly performed, it destroys all parasites or disease germs existing in it. Meat is commonly cooked by boiling, stewing, roasting or baking, broiling and frying. _ _ Boiling.- — In the military service, boiling is a much abused method of cooking. The object of boiling is ordinarily not to extract the constituents from meat, but rather to retain its flavor and nutriment. Hence the piece to be cooked should be large — about five poimds — and should be plunged at once into boiling water, to coagulate the albumen of the outer layers and thus retain the juices. If this is not done, much of the nutritive sub- stance passes into the flmd. The actual period of boiling should not last longer than a few minutes ; the temperatiure should then be lowered and the cooking conducted at a heat at about 160° to 180° F. This is the true cooking point of meat, since above this point the albuminous material becomes completely solidified and, from its hardness, indigestible. Over- heating is therefore to be avoided — and the slower the cooking the better the result. Usually meat is boiled fifteen minutes for each pound of its weight. Eapid boiling is to be avoided ; additional heat is not generated by furious boiling, and much of the volatile principles escape when steam is rapidly generated. The use of the kitchen thermometer by inexperienced cooks is much to be desired in both boiling and stewing. As ordinarily prepared, boiled meat is somewhat tasteless and comparatively less diges- tible. The flavor of meat depends upon the extractives present, and these are liable to be removed to considerable extent by this method of cooking. After prolonged boiling the muscular fibres approach the condition of gela- tin, a substance possessing but slight nutritive value. Vallin found that after four hours of bo ilin g the internal temperature of a joint of beef at- tained 90° to 100° C. While this temperature destroys organic life it does not destroy the harmful qualities of ptomaines. Stewing. — ^This, when properly conducted, is an admirable way of preparing meat. It is much used in foreign armies but has never become popular in our own service. In stewing, small pieces of the meat should be placed in a little water and the whole maintained at a temperature of 140° to 145° F. for several hom-s. Very high temperatiires, which co- agulate and toughen the albumen, defeat the object of stewing, in which the effort is made to dissolve out as large a proportion as possible of the juices of the meat. When stewing is employed the accompanying liquid should be served with the meat ; the two dishes combining all the nutritive 234 THEORY AND PEACTICE OF MILITARY HYGIENE. principles to be found in roast or boiled meat and at the same time pre- senting them in a form very easy of digestion and acceptable to the palate. For stewing meat the ordinary water-bath, made on a larger scale, is an excellent cooking apparatus and deserves a place in all company kitchens. In its absence a satisfactory substitute may be improvised. That very high temperatures are quite unnecessary for stewing is shown by the successful results given by the use of the Norwegian stove, to which reference is made, in another section. ' When it is desired to extract aU the goodness of meat to form a soup, the meat should be finely cut up and placed in cold water. After it has soaked for a while, heat should be applied slowly. If a broth is to be made, the heat, though constantly applied, is not allowed to reach boiling for some time, much of the albumen being thus extracted before coagula- tion has taken place; most of the natural juices having passed into the broth, the meat is left tasteless but still not without some nutritive value. In the making of soup the same procedure is adopted, but simmering is. continued longer, as is also the boiOng; more of the gelatin being extracted and little of the meat being left except as innutritions and tasteless fibre. The difference between a broth and a soup is, therefore, merely one of degree. Roasting. — By roasting is properly to be understood that process by which joints or large pieces of meat are cooked by the direct heat of a fire,, without interposition of utensils and generally in the open air. This method is at present rarely employed except by individual soldiers in the field, baking being substituted for it. When properly carried out the re- sults are excellent, but in practice this is infrequently the case. Broiling. — ^This is the same in principle as roasting, but the scorching of the surface is greater, owing to the larger surface exposed to the heat. The pieces also are smaller and are usually cut in slices. In broiliug the article should be tiuned frequently so as to have it cooked evenly. It is better to broil before a fire than over it, since in the latter case the fat and juices fall into the flames and tend to give a smoky flavor by then igni- tion. Broiling is rarely used in our service. In the field it occasionally happens that soldiers toast their meat ration before the fire, but such meat is apt to be scorched or imperfectly cooked and the result is usually unsat- isfactory. Baking. — Baking, miscalled roasting, is usually employed in cooking the beef and mutton components of the ration. The temperature of the oven is best maintained at about 400° F. This may be determined by the thermometer ; but ordinarily the naked hand and arm are thrust into the oven, and if it can be held there for fifteen seconds the temperature is about right. Experienced cooks are able to make accurate estimations of temperature by this method. Owing to the limited ventilation of the oven the volatile principles are largely retained in the meat. Meat is more savory when roasted than when boiled or stewed, the juices being retained by the protective coating of albumen formed by the high temperature. In all roasting processes, to hasten the course and prevent burning of the su- perficial parts, the joint should be basted or kept constantly enveloped in a coating of hot melted fat ; this, while assisting in the communication of heat, preventing undue evaporation of the juices. In general, about two THE EATION. 235 and one-half hours are required to cook a ten-pound roast. It should be appreciated that the temperature in the centre of a roast of beef of moder- ate size remains much below the temperature of boiUng, albumen being readily coagulated at a far lower temperature. Vallin foimd that the cen- tral temperattue of a large roast frequently did not reach 55° C, even when the temperatvu-e of the periphery stood at 120° to 130° C. It is thus apparent that roast meat may be dangerous iu spite of cooking as commonly performed. Frying. — This, generally speaking, is a bad way of cookiag. In the field it is probably the most convenient way of preparing the meat ration ; and imder such circumstances the stimulation of the digestive functions, through hard exercise in the open air, undoubtedly does much to diminish its harmful effects. Where much grease is used, and this is raised to a high temperature (400° F.) before the meat is added, but little fat is ab- sorbed by the latter, siace the great heat at once creates a protective coat- ing of coagulated albumen on the outside of the meat. If, however, the fat is not hot enough or is chiRed by dropping too much in it at one time, the meat will absorb it and suffer marked deterioration iu digestibility and flavor. The latter method is unfortunately the only one ordinarily avail- able to the soldier on campaign. When heated slowly, fat undergoes de- composition into glycerin and fatty acids — ^the latter materially retarding digestion. When little jets of smoke issue from the melted fat, a suitable temperature for frying has been attained. In garrison, fried foods should always be drained a few moments in a sieve or colander to remove excess of grease. FISH. Fresh Fish. — The place of fish in the diet, if judged by its composi- tion, is the same as that of meat ; it being supplementary to the vegetable foods, most of which are deficient in protein — ^the chief nutrient in fish. Fresh fish, when obtainable, makes a useful variation in the diet, but should not be too frequently issued. Troops soon tire of it ; besides which its flesh contains so much water, and the wastage incident to its prepara- tion for the table is so great, that the ration of fresh fish, from a nutritive standpoint, is far inferior to the ration of fresh meat. Ordinarily, when dressed for cooking, the entrails, head and fins — and, less frequently, the bones — are removed. This entails a considerable loss in weight as well as of nutritive material. It has been assumed, as a result of numerous in- vestigations, that in dressing fish the following percentages are lost: Large-mouthed black bass, sea bass, cisco, kingfish, mullet, white perch, pickerel, pike, tomcod, weakfish and whitefish, each 17.5 per cent. ; smaU- mouthed black bass, eel, Spanish mackerel, porgy and turbot, each 13.5 per cent.; butterfish, 12.5 per cent.; shad, 11 per cent.; brook trout, 16.5 per cent. More recent figures for loss in weight in dressing are as fol- lows: Bullhead, 50 per cent. ; buffalo fish and lake sturgeon, 40 per cent. ; carp and sucker, 35 per cent. ; fresh-water sheepshead, 23 per cent. ; grass pike, black bass, white bass, yellow perch and salmon, 15 per cent. ; eels, 10 per cent. Fish is less satisfying and not so stimulating as the flesh of animals. Contrary to accepted ideas, experiments indicate that fish is less quickly 236 THEORY AND PEACTICE OF MILITARY HYGIENE, digested than beef, being about equal to lamb in this respect. However, the difference in digestibility of fish and meat is not very great, tod before sweeping deductions are made the thoroughness as well as rapidity with which fish is digested should also be taken into accoimt. A nimiber of experiments have been made on man with reference to the completeness with which fish is digested, and these show that fish and lean beef are ultimately about equally digested. Langworthy states that about ninety- five per cent, of the total dry matter, ninety-seven per cent, of protein and over ninety per cent, of the fat are utilized in the human organism. In general, the digestibility and flavor of fish depend upon the proportion of fat it contains. This varies largely with the species ; but white-fleshed fish have little fat while those with darker meat are rich in this substance. Salmon has considerable fat and approaches beef in composition. The preference for fresh-water or salt-water fish is a matter of individ- ual taste. Both are wholesome. The market value of fish is affected by various conditions, among which are the locality from which they come, the season in which they are taken and the food on which they have grown. In general, it may be said that those from clear, cold or deep water are preferable to those from shallow or warm water, while fish taken in waters with a rocky or sandy bottom are preferable to those from water with a muddy bottom. Some fish, for instance shad, are at their best dur- ing the spawning season, while others should not be eaten during this pe- riod. Those fish which feed on small Crustacea and other forms of animal and vegetable life are preferable to those living upon sewage and other matter which may contaminate the waters. The mode of capture of fish affects their value as food. Those caught by the giUs and allowed to die in the water by slow degrees, as is the case where gUl nets are used, im- dergo decomposition very readily and are inferior for food. Fish are often landed alive and allowed to die slowly. This custom is not only inhumane but lessens the value of the fish. It has been foimd that such as are killed immediately after catching remaia firm and bear shipment better than those allowed to die slowly. The quality of the fish is often injured by improper handling before placing on the market. The majority of fishes are iafested with different kinds of parasitic worms. The only one known with any certainty, however, to be conveyed to man is the Bothriocephalus latus. The encysted stage of this worm is passed in either the pike or turbot. Fish, particularly decomposed and some preserved fish, contain various kinds of bacteria which are often of a pathogenic nature. The flesh of apparently healthy fish may produce poisonous symptoms. There is no evidence that such fish are diseased and the flesh may not appear to be decomposed ; it at times produces, however, violent symptoms of two kinds — gastro-intestinal irritation and severe ataxic nervous symptoms, with great depression and algidity. The herring, flatfish and others have at times been known to cause these effects. Mackerel also has produced poisonous symptoms, probably through rapid decomposition — for when such fish are cooked immediately after being caught they do not appear to produce any bad effect. The formation of ptomaines quite generally, although not always, accompanies putrefaction. Fish which have been frozen and, after thawing, kept for a time before being cooked are especially likely to contain injurious ptomaines. THE RATION. 237 In examining fish the inspector should satisfy himself as to the matter of freshness. Fresh fish is firm and stiff; the drooping or not of the tails is a fair criterion ia this respect. Flatfish keep better than herriags or mackerel. Cod, haddock and whitiag keep the best, particularly if rinsed with salt water and stored in a cool place. AU fish intended for food should be unbruised, unbroken and clean. If the scales are duU and damaged it is very suggestive of either ill-usage or staleness ; softening in places indicates the same. It is an established fact that decomposition in the surface fishes, such as herring, mackerel and mullet, is extremely rapid. Ground fish, like halibut, cod and plaice, decompose much less rapidly, and if properly packed may remain fresh and fit for human food from seven to ten days after being taken from the sea. Fish which have been ungutted are the most difficult to inspect, more especially those with large, oily livers. Externally such fish appear good, the eyes being bright and gills red, but internally they are fiill of decomposition and decay. On strong pressure between the thumb and fingers the deeper flesh readily crushes, leaving only the skin between the fingers. This is an infallible test of imsoundness. Immediately after death the blood of fishes becomes coagulated. When decomposition sets in, on cutting the flesh, this blood win run out as a liquid of a dull red color, giving off an offensive smell. On removing the bones, in such cases, each one leaves a dull red mark, showing where the processes of decomposition are extending to the more solid portions of the fish. To avoid rapid decomposition, aU fish should be at once bled and gutted on being caught. The allowance of fresh fish in the ration is eighteen ounces. As al- ready stated, however, this quantity is so reduced by unavoidable wastage, and the meat is so watery in character, that it is far inferior in nutritive value to the ration of animal flesh ; the legal allowance of whole fresh cod- fish furnishing one hundred and fifty -five Calories where the ration of fresh beef supplies eleven himdred and eighty Calories. It is therefore evident that fresh fish, in the quantity authorized, is not suited for use by troops during periods of hard work ; and even in garrison it should never be em- ployed more than once weekly. As a general thing the wastage in fresh fish and its lack of a satisfying character are appreciated by company com- manders, and issues of fresh .fish are rarely made by the Subsistence De- partment — such fish as are desired being purchased from the company funds. The variety of fish which may be used as food is almost infinite ; but taking into consideration the stations at which our troops are serving, the more important species which may presumably from time to time enter into the subsistence of the soldier — ^together with their chemical composition — wiU be found in the following table. Whole flsh. Water, per cent. Protein, per cent. Fat, per cent. Fuel value per pound. Calories. "Rat^q black 34.6 34.8 31.4 40.3 38.7 33.6 61.9 9.3 8.7 7.4 10 8.4 5.4 15.3 0.8 .2 .7 .6 .3 .3 - 4.4 305 Tiass sea 170 Blackfish 165 T51iipflah 310 Cod 165 115 470 238 THEORY AND PEACTICE OP MILITAEY HYGIENE. Whole flsh. Water, per cent. Protein, per cent. Fat, per cent. Fuel Talue per pound, Calortes. 41.7 40.4 31.5 28.4 30 29.7 39.5 42 40.9 35.2 26.9 46.1 40.4 38.0 11.2 10.2 8.2 7.3 6.6 6.6 10.3 10.8 15.3 9.4 6.6 10.1 9.9 8.6 3.9 4.2 2.0 1.5 .2 .4 4.3 .6 8.9 4.8 .2 1.0 1.1 1.1 375 Monkprel . 365 Mullet 235 T*fT*rh white 200 130 Pike 135 375 335 660 Shad 380 Shpfnshpad 130 Smelt 230 Trout 230 Weakfish 305 In its preparation, fresh fish is commonly boiled, steamed, broiled, fried or baked ; or it may be combined with other materials ia some made dish. When boiled, it is stated that the loss in weight ranges from five to thirty per cent., according to the species and length of cooking. One ex- perimenter gives twenty-six per cent, as the average. This loss is largely made up of water, and little fat or protein is lost. So far as known, ex- periments have not been made which show the losses by other methods of cooking than boihng. It is probable, however, that there would be a very considerable loss of water by any method. Dried Fish. — This, under favorable circumstances, is capable of pres- ervation for at least a year ; but the process of curing not only modifies the flavor but impairs digestibility. Preserved fish, as a rule, show a small percentage of refuse, with the exception of a few kinds which are preserved whole. The percentage of actual nutrients is naturally much larger than in the corresponding fresh fish, owing to the removal of a large part of the refuse and considerable fluid. The gain in nutrients is chiefly represented by protein, which is the most valuable nutrient. The allowance of dried fish, issued in the form of codfish, is fourteen ounces ; the chemical com- position of dry salt cod, as issued, being as follows : Water, per cent. Protein, per cent. Fat, per cent. Fuel value per pound. Calories. 40.2 16.0 0.4 315 Bad codfish has a disagreeable odor and its hardness and consistency are notably diminished. In color such codfish is frequently reddish, the latter being due to a development of a growth — the Clathrocystis roseopersinica, according to Viry — which is of itself not poisonous but may often be a sign of the development of micro-organisms of a dangerous character. This red growth can be prevented by salting the codfish with a salt con- taining sodium sulpho-benzoate in the proportion of five per cent, by weight, or by dusting the fish with boracic acid. In the French service, where fish is regularly issued on Fridays, several outbreaks of ptomaine poisoning have followed the use of spoiled codfish. These outbreaks close- ly resembled those due to the use of meats of bad character. THE KATION. 239 Brieger has isolated a ptomaine from putrid codfish, which he considers identical with muscarin and which gives symptoms analogous to those f ol- lowiag the use of poisonous toad-stools. There appears reason to believe that where fish are originally unsound, the processes of salting and drying serve to increase the capabilities of the fish as regards the production of irritant symptoms. Care should be taken to see that codfish issued to troops is new, firm and white ; and that it readily softens when placed in cold water and the latter brought nearly to the boiling point and kept at that temperature for an hour. Pickled Fish. — The allowance of pickled fish is eighteen ounces, salt mackerel usually being employed for this issue. Pickled fish is rarely drawn, and then only for the sake of variety. It is not relished to any great extent by troops and could well be dropped from the ration. Its keeping qualities are, however, better than those of dried fish. The chemi- cal composition of salt mackerel is as follows : Water, per cent. Protein, per cent. Fat, per cent. Fuel value per pound. Calories. 34.8 13.9 21.2 1,155 Pickled fish should be stored in a cool, damp place and be kept well brined, as they soon become rusty and impaired in quality if the brine leaks out and leaves them dry. Canned Fish. — Canned salmon is employed with advantage, as part of the ration, in the quantity of sixteen ounces. It is palatable and diges- tible, and its nutritive value, for fish, is relatively high. Used as an occa- sional substitute for meat it gives a welcome variety to the diet, especially for the lighter meals of the day. The fish is canned in its own juice and the original flavor is largely retained. In composition, canned sahnon com- pares favorably with the fresh article. Generally speaking, the amount of refuse is small, since the portions commonly rejected in preparation for the table are also removed before canning. The following is the chemical composition of canned salmon : Water, per cent. 56.8 Protein, per cent. 19.5 Fat, per cent. 7.5 Fuel value per pound. Calories. 680 Canned fish should never be allowed to remain long in the can after opening, but should be used at once. There is some possibility of danger from the combined action of the can contents and oxygen of the air upon the lead of the solder or the can itself. Furthermore, canned fish seems peculiarly suited to the growth of micro-organisms when exposed to the air, and the production of poisonous ptomaines is extremely rapid, espe- cially under conditions of warmth, moisture and a deficient supply of oxy- gen. 240 THEORY AND PRACTICE OE MILITARY HYGIENE. THE BBEAD AND VEGETABLE COMPONENTS. Flour. — ^The inspection and preparation of grain, in the manufacture of flour, does not concern the military sanitarian, who has merely to do with the finished product. In the United States service wheat flour only is used, but in some northern countries, notably in Germany, where the production of wheat is less extensive, rye flour is much used in the prepa- ration of bread for the soldier. On account of the variation from the normal in the chemical compo- sition of the wheat from which it is made, arising from the peculiarities of the kind of wheat or of the soil on which it was grown, or the meteorolog- ical conditions which prevailed during its growth, or a combination of these factors, flour wiH generally be deficient in some and redundant in other chemical elements essential to the production of good bread of proper nu- tritive value. These faults are, however, readily corrected by the miHer, by properly mixing one or more brands of spring wheat flour with one or more brands of winter wheat flour. To make bread of proper nutritive value and wholesomeness, " straight " flour — which contains aU the ele- ments of the fully developed wheat grain, except the husk or bran^ — ^is es- sential, and flour of this character is the variety supplied for issue as a component of the ration, the daily allowance per man being eighteen ounces. The average chemical composition of such flour is as follows : Water, per cent. Protein, per cent. Fat, per cent. Carbohydrates, per cent. Fuel value per pound. Calories. 13.8 10,8 « 1.1 74.8 1,640 Where large lots of flour are to be purchased or issued, the samples should be examined microscopically, physically, chemically and practically by making bread. This is particularly necessary in time of war, when flour is more liable to be adulterated by unscrupulous contractors. Detec- tion of any such adulteration should be followed by the severest punish- ment of those responsible. Eiordan states that : " The prompt action of the Russian authorities, during the Eusso-Turkish campaign, on discover- ing that the flour furnished by the head of the commissarial department contained a large proportion of terra alba, is to be commended. The man who endangered the success of the enterprise was immediately shot for his dishonesty." Ordinarily, when flour is purchased in small quantities-, the physical and practical examinations wiU be sufficient. In appearance, flour should be of a warm white color, not a chalky white. The latter indicates deficiency in strength from over-grinding, which removes too much of the gluten and leaves the starch element too prominent. A bluish tinge indi- cates the presence of cockle seed — a small black seed borne by a weed which grows among the wheat — or smut, a fungous disease to which wheat is liable. The color which flour wiU give to bread made therefrom can be shown by placing a flattened ball of dough on a piece o^ window-glass and noting the color of the bottom through the glass after twenty-four hom's. THE RATION. 241 On touching the flour there should be no lumps, or, if there are, they should at once break down on light pressure. There must be no grittiness ; which shows that the starch grains are changing, are adhering too strongly to each other and will give an acid bread. There should, however, be a certain amount of cohesion when a handful of flour is compressed. "When flour is damp it should be rejected without question. This condition is indicated by the possibility of rolling a pellet of it between the thimib and finger, or by the general feeling of moisture perceptible in running the open hand through it. Where more exactness is required in determining the water, the following method may be employed: Weigh 1 gm., spread it out on a dish, and dry either by a water-bath, or in a hot-air bath or oven, the temperature not being allowed to go above 212° F. The flour must not be at aU burnt or much darkened in color. Weigh directly the flour is cold ; the loss multiplied by one himdred is the percentage of water. The range of water is from ten per cent, in the best dried flours to eighteen per cent, in the worst. The more water the greater the liability of change in the flour and the less is the amount of nutriment supplied by a given weight. If, then, the water be over eighteen per cent., the flom- shoiild be rejected; if over sixteen, it should be regarded as of inferior character. Moisture, in the presence of heat, favors the development of the bacteria by which fermentative changes are produced. Fermenting flour produces gastro- intestinal disorders. The heat and moisture of the stomach doubtless ex- cite at once very rapid fermentation, carbon dioxide is rapidly developed; hence uncomfortable feelings, flatulence, imperfect digestion and diar- rhoea. 11^ is to remedy this condition of the flour that alum is added, and some of the effects ascribed to alum may be really owing to the bad character of the floxu: itself. In some instances the flour may have been originally good, but altered either from age or imperfect drying. The bread made from such flour is often acid, and sometimes highly so, suffi- cient to produce diarrhcea ; though such bread has sometimes been used for a long time without this effect — usually soldiers will not eat much of it and thus their supply of nutriment is lessened. The taste of flour must not be acid, although the best qualities are slightly acid to test paper. If flour does not have the taste of sound, freshly-ground wheat meal, or if it has a sour taste or a musty, mouldy or earthy taste or odor, however slight, it should be rejected. Earthy smell- ing flour is made from wheat which has been exposed to dampness while in the straw. Bread made from such flour is clammy, heavy, dark-colored and unwholesome. To determine whether flour has absorbed any foreign odor, three or four oimces of it should be placed on a plate and drenched with boiling water. If contaminated in the above respect the foreign odor is readily noticed in the vapor. The quantity and quality of the gluten present in a flour is a matter of great importance, and different kinds of wheat vary greatly in this respect. Gluten has a high nutritive value as an easily digested proteid; mixed with water it forms a tenacious, elastic body, which expands under the pressure of the gas from the yeast imtil the dough is full of vacuolations whose walls of tough gluten do not allow the contained gas to escape, and thus make the dough light and porous. The so-called hard wheats are rich in gluten of a strong, tenacious character, while soft wheats contain less glu- 16 242 THEORY AND PEACTICE OF MILITAEY HYGIENE. ten and proportionately more starch. The gluten of hard wheat can be mixed with large amounts of water, and produces a large loaf from a com- paratively small quantity of flour. Soft wheat, on the other hand, while it does not yield so large a loaf, makes a bread containing less water and having a milder and more agreeable flavor. In general, flour containing a satisfactory proportion of gluten should stick to a perpendicular flat surface when thrown against it. The strength of flour, or the amount and quality of its gluten, can also be determined with sufficient accuracy for all practi- cal purposes from the elasticity and other characteristics of its dough. For this test, two ounces of the flour are mixed with one fluid-ounce of water - — good flour absorbs water in about this proportion — and the mixture is thoroughly kneaded into a dough. The latter is then moulded into the form of a cylinder about two and one-half inches long and one and three- fourths inches in diameter. It is then placed on end on a flat surface and allowed to remain half an hour. If it stands up and retains its form well, and has acquired a hardened, dry surface, it is evidence of the sufficiency and good character of the gluten. If it falls, flattens or "runs," it is evi- dence that the gluten is deficient in quantity or quality — or both. If dough which has stood the first test satisfactorily be flattened out by pull- ing it around the ends until it is so thin as to be transparent, it is further evidence of good character ; and if, when rolled in the form of a thin cylin- der, it is pulled gently at the ends and the tension then relaxed, the dough retracts on itself and resumes its former shape, no further evidence as to its good character is required. The gluten may be determined with accuracy by weighing out 10 gm. of the flour and mixing it into a dough with a glass rod while water is slowly added from a burette. The dough is then allowed to stand about fifteen minutes, at the end of which time a little water is added, the dough worked with the rod and the starch poured ofi'. This process is continued until the dough is so coherent that it can be worked with the fingers, when it is manipulated until the water which comes off is quite clear. The gluten is preferably weighed after drying on a water-bath. If weighed in the wet state the gross weight should be divided by 2.9 to get the amount of dried gluten. Dry gluten usually ranges from eight to ten per cent. ; flour showing less than eight per cent, should be rejected. Flour is in its best condition one to three months after milling. After this period it does not improve and ultimately undergoes deterioration. Animal and vegetable parasites appear in it, and its acidity increases rapidly and progressively. Under ordinary conditions, the period of good preservation of flour does not extend beyond a few months. In general, flour made from winter wheat has superior keeping qualities. No floiu', however, will keep unless made from sound and weU- Fio. 79.-Tyrogiyphus cleaned wheat. The minute so-called flour mite — longlor. (Much en- rp i i i • • , larged.) iyroglyphus longior — is by no means uncommon m old, inferior flour, especially if it is damp. Its occur- rence does not necessarily indicate that leguminous seeds are present, as sometimes stated. The presence of these mites always shows that the flour is beginning to change. A single mite may occasionally be found THE EATION. 243 in good flour, but even one should be looked on with suspicion, and the flour should be afterward frequently examined to see if they are increas- ing in numbers. These insects are capable of passing into a resistive stage in which they can exist without food for many months. If a store- house be once infected, their extermination is a matter of considerable difliculty. Several species of little flattened beetles, of a shining brown color and similar appearance generally, so frequently occur in bags and barrels of flour as to have earned the popular title of "flour weevils." They live upon cereals and other seeds and various other stored products, but gener- ally prefer flour and meal and articles of diet containing farinaceous matter. Their eggs are often deposited in the flour in miUs, and these and the larvae Via. 80.— TrlboUum confusam. a. Beetle ; 6, larva ; c, pupa. (All much enlarged.) they produce, being minute and pale in color, readily escape notice; but after the flour has been barreled or placed in bags and left unopened for any length of time, the adult beetles make their appearance and in due course the flour |is ruined, for when the insects have time to propagate they soon convert the floiu' into a gray, useless mass. A part of the an- noyance is due to the fact that the insects are highly offensive, a few specimens being sufficient to impart a disagreeable and persistent odor to the infested substance. While there are several allied varieties of these flour beetles, the most important is the Tribolium confusum, which is said to be the most destructive of all insects to prepared cereal foods. The mature insect is shining brownish-red in color, and is about one-sixth of an inch long. Somewhat rarer pests are the larvse of various kinds of moth, more particularly Ephestia kuehniella, belonging to the micro-lepidoptera. In this insect the adult moth has a wing expanse of a little less than an inch ; the fore-wings are pale leaden-gray, with transverse back markings of the pattern shown in the accompanying illustration; the hind-wings are dirty whitish, semi-transparent, and with a darker border. The caterpillar is whitish and hairy. The chrysalis is reddish-brown. For the destruction of all these flour insects exposure to weak fumes of sulphur dioxide is ef&cacious ; but the quality of the flour is somewhat 244 THEORY AND PEACTICE OF MILITARY HYGIENE. injured for bread-making by this treatment. The method now generally adopted by millers for destroying these insects consists in spreading out the iiour, so as to expose a reasonably large surface, in a small, fairly tight room. Bisulphide of carbon is then evaporated in shallow dishes, or on bits of cloth or cotton waste, distributed about on the surface of the infested material. The liquid rapidly volatilizes, and being heavier than air, the vapor descends and kills the insects in the flour or grain. While this liquid has a strong, disagreeable odor, this soon passes away. Its inflam- mability should be remembered. One ounce of the bisulphide is said to be sufficient for one hundred pounds of flour. For the fumigation of in- fested storehouses one pound to each one thousand cubic feet of space is required. In flour which has gone to extreme decomposition, and is moist and becoming discolored, moulds and various forms of bacterial life are fre- quently seen. They cannot be mistaken. Fig. 81.— EphesUa kuebnlella. a. Moth ; c, larva ; d, pupa. (Enlarged.) Good flour cannot be made from sprouted wheat, because such wheat has undergone more or less fermentation and, although it may be given a satisfactory appearance by careful milling, it will not ferment sufficiently to make good bread. Such flour feels heavy and is dull, flat and lifeless. The dough made from flour of this character has a rank odor, and the bread is moist, heavy and dark colored. Occasionally flour from wheat grown on sandy soU, or where lime is deficient, may rise well enough, but the bread becomes heavy and sour when it cools. This is especially the case with Arizona-grown wheat. Good bread may be made from such flour by the use of lime-water. The impurities which may accidentally gain entrance to a bag of grain, or even into the flour made from it, consist chiefly of the seeds of other plants and of blighted or moulded wheat. The foreign seeds most to be dreaded are perhaps cockles and darnel, and both should be carefully guarded against — cockles because they injure the color of flour and bread,, and darnel because it is commonly regarded as poisonous. Other foreign seeds may not be equally dangerous, but they should be removed with equal care as they lessen the nutritive value and strength of the flour. In the United States there is undoubtedly little attempt at the adultera- tion of flour offered for military use. The adulterants which are most com- monly used abroad are rye flour, corn (maize) flour, rice meal, potato starch and meals from various leguminous plants, such as peas or beans. They are not harmful in the food and sometimes improve the color of the bread ; nev- THE EATION. 245 ertheless they are fraudulent because they lower the quality of the flour without harming its appearance. The mixture is sold as flour, and thus the Government would secure an adulterated article under a false name and at the same price as pure goods. The nature of these grains can be determined by the microscope. Mineral substances, such as alum, borax, chalk and carbonate of magnesia, are occasionally put into the flour to whiten it or to neutralize its acidity; but these are more often used by the baker than by the miller. When flour is suspected of adulteration with a mineral substance, it should be strongly shaken with chloroform. The flour floats, while aU mineral matters fall to the bottom. Many other tests are given for the detection of special miueral substances, but these will rarely be required in the inspection of floiu: for the military service. Flour keeps, best in cool, dry and weU-ventilated storage. Extremes of temperatme should as far as possible be avoided, nor should flour be ex- posed to a freezing temperature. It is pecidiarly sensitive to exhalations from other substances, and, therefore, should not be stored in proximity to articles which give rise to powerful or unpleasant odors. In general, flour sacks should be packed in tiers, but caking occurs in the lower layers if the tiers be too high. Bread. — This, the other important part of the ration with meat — for practically bread and meat make up its nutritive value — is the only portion of it in which there is practically no imavoidable waste. Further, bread is very completely digested. It is not, however, a complete diet; being somewhat deficient in nitrogen and markedly so in fats. Greasy food is eaten with it by instinct, and unless fats are supplied, as bacon or rich gravy, it will often be wasted by troops. When used with other foods in proper proportion, it is much appreciated and can be eaten indefinitely without becoming distasteful. The allowance of soft bread is the same as that of flour, eighteen ounces. It is possible, however, to increase the bread ration to the full extent of the flour ration, or any part thereof, imder the concurrent authority of the post council of administration and the commanding officer. Under ordi- nary circumstances in civil life a pound of bread is made from three-fourths of a pound of flour — ^the additional weight being due to the water required in the process. With some flour five to ten per cent, more water can be absorbed, and in the military service the saAongs oh a hundred-weight of bread are ordinarily calculated at about thirty -three pounds of flour. On the other hand, since many of the compounds formed during the fermenta- tion process are either gases or are volatile at the temperature of baking, appreciable losses of dry matter necessarily take place. These losses are usually estimated at about three or four per cent, of the flour used. The chief difference in the composition of flom* and bread is the proportion of water, which makes about one-eighth the weight of flour and one-third that of the bread. The average composition of bread, such as is used in otu" service", is as follows : Water, per cent. Protein, per cent. Fats, per cent. Carbohyarates, per cent. Fuel value per pound. Calories. 35.4 9.5 1.2 52.8 1,244 246 THEOEY AND PRACTICE OF MILITARY HYGIENE. Where carbon dioxide is in any way formed within or forced into the interior of dough, so as to divide it iato a number of miaute cavities, bread is made. There are practically two kinds of bread — ^that made by means of yeast and that aerated by chemical means. In the first, the action of the yeast and heat results in fermentation of the carbohydrates and the production of carbon dioxide and alcohol; the production of soluble carbo- hydrates, as dextrin, from insoluble forms, as starch; the production of lactic and other acids ; the formation of other volatile carbon compounds ; the partial oxidation of the fats. Besides these there are many other changes, the nature of which is less weU understood. The ordinary process of bread making consists reaUy of three stages — ^namely, the preparation of the leaven or ferment, the preparation of the sponge and the making of the dough. The ferment is made by mashing boiled potatoes into a thin paste, cooling to about 80° F., adding sufficient good yeast and a little flour. The mixture is set aside in a warm place for about five horn's ; at the end of which time the yeast is very active and maltose, dextrin and peptone-like bodies have been found in the mixture. To this ferment, when ready, about one- third the flour to be used is added, together with sufficient water to form a stiff dough and a little salt. The resulting mixture constitutes the sponge, in which very active fermentation goes on. After about five hours the sponge breaks, owing to the development of large quantities of carbonic acid and alcohol from the maltose and dextrin. When the sponge has broken twice, the dough is formed by adding to the sponge the remainder of the flour and sufficient water. This rises in an hour or so, and is then transferred to an oven for an hour and a half. Though the temperature of the oven varies from 400° to 450° F., the actual temperature of the dough does not rise much over 212° F. In this stage the chemical processes are not very active ; but the bread gradually becomes well aerated and its con- stituents, undergoing a kind of automatic digestion, improve both in flavor and aroma. MUitary bakers almost invariably prefer to use potato yeast rather than the compressed article. The so-called " salt-rising " bread is interesting as an illustration of self-raised bread. In it the ferments originally present or acquired from the air produce the fermentation which leavens it. To make it, warm mUk and corn-meal are mixed together into a stiff batter, which is left at blood heat until the whole mass is sour. Next a thick sponge is made of wheat flour and hot water, in which a little salt has been dissolved. This sponge and the sour batter are thoroughly kneaded together and set in a warm place for several hours. The leavening action started in the batter spreads through the dough and produces a light, porous loaf, which many persons consider very palatable. Such bread is quite free from acidity, as the presence of the salt prevents imdesirable fermentation. On an average there is about one per cent, by weight of alcohol pro- duced when bread is made. It serves a useful purpose, since, in baking, the alcohol is volatilized, and the vapor aids the carbon dioxide in expand- ing the dough, thus making the bread more porous. Notwithstanding the loss of carbohydrates caused by the production of alcohol and carbon dioxide, fresh breads ordinarily contain from three to four per cent, of solu- ble carbohydrates. Allowing for average losses of carbohydrates by fer- mentation, not far from six to eight per cent, of the total insoluble starch, THE KATION. 247 origiDally present in the flour, is changed to soluble forms during the bread- making process. There are also other changes which the starch has under- gone which are not shown by chemical analysis. By the combined action of the ferments and heat the forms of many of the starch grains in bread are materially changed. When bread is extracted with alcohol and water to remove a part of the proteids and the soluble carbohydrate bodies, the form of the starch grains may be distinctly seen. Many of these appear as if they had been partially digested, and many pieces of disintegrated starch granules are present. In some cases the outer layers of the starch grains appear as if they had been subjected to pressure and partially rup- tured. Many of the smaller and medium-sized grains appear unaltered. These physical changes which the graias have undergone during the bread- making process doubtless render bread, when properly made, more sus- ceptible to the action of solvents, as the digestive fluids. In the non-fermented breads the necessary carbon dioxide is ordinarily generated by mixing sodium or ammonium carbonate with the dough, and adding hydrochloric, tartaric or citric acid. Baking-powders are com- pomids of these substances, well mixed and preserved in a dry state. The chief objections to such yeast substitutes are that imless carefully prepared they may be inefficient or harmful, that they are easily adulterated and that bread made from them is usually rather tasteless, lacking the flavor and aroma which good yeast imparts. Alum is often added to whiten bread and stop an excess of fermentation. It is frequently present in bak- ing-powders, and when in excess interferes with digestion. The "aSrated" or Dauglish patent bread may here be mentioned. In this method the water used for wetting the dough is directly charged with the requisite amount of carbon dioxide gas, and then mixed with the flour in a specially constructed machine. Sometimes a little fermented barley infusion or wort, from a brewery, is put into the water. This aids it in absorbing the gas, renders the gluten more elastic and improves the flavor of the bread. JSTotter and Firth state that about twenty cubic feet of CO^, derived from chalk and sulphuric acid, are used for two hundred and eighty pounds of flour; and that about eleven cubic feet of the gas are actually in- corporated with the flour. It is claimed for imfermented breads that they do not contain alcohol, acetic acid and other products of excessive fermenta- tion, but the advantage is a doubtful one, as the action of yeast partially digests the starch, changing it into maltose and dextrin, while the pro- teids of flour are also largely converted into albumoses or other peptone- Kke bodies. In general, it should not be forgotten that the lightness and sweetness of bread depend as much on the way in which it is made as on the materials used. On pressing in a well-baked loaf of bread, without, however, breaking the surface, it should, if properly baked, spring back into its original shape. In good bread not less than thirty per cent, of crust should be present, this being yellowish brown, firm and not aerated. The external surface should be caramelized but not burned. The amount of crust is readily determined by paring it off with a sharp knife and weighing. The crumb should be permeated with small, regular cavities and no part should be heavy or without these small cells. The partitions between the cavi- ties should not be tough, the color should be white and the taste not acid. 248 THEORY AND PRACTICE OE MILITARY HYGIENE. even when held in the mouth. If the color changes soon, and fungi de- velop, the bread is too moist ; if sodden or heavy the flour is bad, the bak- ing at fault or the sponge badly set. In the military service, bad bread is generally due to carelessness or inexperience on the part of the baker rather than to defect in the raw materials employed. From the cheapness of flour, bread is rarely adulterated in this country — except where mineral salts are mixed into the dough for the purpose of producing a good-looking loaf from poor flour. Alum is the most common of these. It tends to check the action of the diastase and permits a weak " flour to absorb more water than usual. It also improves the color of the bread. Many reliable bakers use it under the impression that it does good and not harm ; but besides producing a bread the nutritive value of which is not so great as appearances indicate, it is believed to be really injurious to the digestive system and must be ranked as an objectionable adulterant. Alum tests are usually made by soaking a sample of the suspected bread in a solution of tincture of logwood and ammonium carbonate, in which alum betrays itself by a bluish color. Copper sulphate is used to produce an effect similar to that of alum in bread, but is believed to be more dan- gerous. Lime exerts practically the same influence and does no particular harm. In the military service bread is ordinarily baked from the flour provided by the Subsistence Department ; and if the quality of the flour be good the pmity of the bread is insured. Under certain circumstances, however, small bodies of troops may be temporarily without facilities for baking their own bread, and in such instances the ration of flour may be turned over to some civilian baker ; he agreeing to supply an equal weight of bread and taking the flour savings for his labor. Under these circum- stances special attention should be given to the quality of the bread — not only as regards the above mineral adulterants but also since dishonest bakers are apt to under-bake the bread so as to retain as much water as possible and thus increase the weight. It is also for their advantage to have the bread weighed out as soon as possible after baking, but this should not be done within twenty-four hours. After being taken from the oven bread begins to lose weight. This loss naturally depends upon size, amount of crust, temperature and movement of air, but in a sheltered place, at ordinary temperature, a two-poimd loaf, baked with crust all over, loses about three-fourths of one per cent, in cooling and from one to one and one-fourth in five hours. A similar loaf, with only top and bot- tom crust, loses three per cent, in cooling and about four per cent, in five or six hours. A loaf with four sides crust loses two per cent, in cooling and retains its weight without much further loss for five hours. For each of six; sides that is not crust there is a loss of weight of about one per cent, in the first five hours. At the end of twenty-four hours the proportion is about one-half more, and the total loss is doubled at the end of seventy- two hours. If the bread is baked in larger loaves the loss wUl be propor- tionately less, the ratio of the evaporating surface to the bulk of the loaf being diminished. In the German army bread less than twenty-four hours or more than four days old is not accepted for issue. Bread may be of bad color from old flour, from grown flour — in which case the changes in the starch have generally gone on to a considerable extent, the bread contains more sugar than usual and does not rise weU — THE EATION. 249 and perhaps from bad yeast. Bread may undergo lactic or butyric acid fermentation from the introduction of specific bacteria. In such instances it frequently happens that the vessels used in preparing the dough were not thoroughly cleaned after the last using ; that the yeast contained an undue proportion of these bacteria ; or, if the latter were found only in nor- mal quantities, the yeast itself may have been weak and quickly exhausted. If the dough stands too long after mixing and the yeast ceases to work, the undesirable bacteria, which grow best in the presence of acetic acid, such as oc^rs after alcoholic fermentation has ceased, may undergo luxuriant development. In certain cases these bacteria may have been originally present in the flour itself and survived baking. Bread which grows sour with age has usually received its bacterial infection from the air. When sour bread has been produced, great cleanliness on the part of the bakers and their utensils should be enforced. When the flour itself is acid, lime water should be used instead of pure water to moisten the dough. The former has the advantage that, while it corrects acidity, it does not check the fermentation of yeast. Bread may sometimes be bitter from bitter yeast — the remedy for this is obvious. One of the most common and dangerous faults in bread is heaviness and sogginess. This fault may be caused by the use of cheap flours, poor in gluten, which cannot absorb all the water -put into the dough, or, to state it in another way, by the use of too much water in proportion to the flour ; by too little or by too poor yeast, or by insufficient kneading, rising or baking. It is said, also, that if the flour has been dried at too great a heat the gluten is altered and the bread does not rise weU. The practice of wrapping freshly-baked bread in cloths during cooling makes it damp and clammy. Heavy bread is one of the most indigestible of foods, since when chewed it rolls itself into solid lumps which afford little oppor- tunity for the action of the digestive juices to act upon them. Occasion- ally the crumb of fresh bread breaks when cut, instead of separating cleanly under the knife. Harsh, dry flours, not sufficiently fermented, may be the cause of this — or the dough may have lost its tenacity by being overworked. Another common fault in bread is a crumb fuU of large, irregular holes instead of th^ small, even pores which it should sh(j,w. These occur in ■over-kneaded or over-raised dough; or if they are found just below the crust they mean that the oven was too hot and that the crust formed be- fore the carbon dioxide had finished expanding. In the course of three- or four days after baking, bread sometimes be- comes sticky or slimy, assuming a light-brown tint and presenting a sweetish taste and peculiar odor. When touched, such bread appears sticky — a condition which ultimately may become so marked as to permit the production of threads which may string out several feet in length. This condition was shown by EusseU to be due to the presence of the ordi- nary potato bacillus — Bacillus mesentericus vulgatus — and it was found that the temperature of the interior of loaves was not sufficiently high to destroy these baciUi in the spore condition. This bacOlus appears to gain access to the bread through the medium of impure yeast. The trouble need not cause any special alarm from a sanitary standpoint, for the organ- ism causing the change is a saprophytic form that is widely spread. As soon as the fermentative change begins to be weU marked it is apparent 250 THEOEY AND PEACTICE OF MILITARY HYGIENE. enough to the taste, so that bread affected with the same would be quickly rejected as food. The remedy consists in careful investigation into the character of the yeast supply, and, if necessary, the storage at a low tem- perature of bread liable to be affected in this manner. Among the various species of bacteria which may occur in bread, men- tion should be made of the Bacillus prodigiosus, the occurrence of which gives rise to blood-red spots in the dough. This micro-organism is harm- less — but from its striking appearance its presence is liable to give rise to considerable apprehension among those less well informed. Bread, especially when moist or stored in a damp atmosphere, often serves as a medium for the develop- ment of moulds, the spores of which are floating everywhere in the air. Balland and Masson state that the temperature in the interior of bread during baking attains a height of 100° to 102° C; This heat, combined with the acidity of the bread, destroys or- dinary pathogenic micro-organisms ; but certain spores of high resisting • powers are capable of subsequent Many of the moulds are probably present in the wheat form of spores, and hence exposure of the bread to the air after baking may not be necessary to induce their development. With the more common varieties of these moulds the sanitary officer Fig. 82.— Aspergil- lus nlger. .4, My- celium and spores ; B, arrangement of . spores (enlarged). (Alter Laveran.) germination, itself in the Fig. — PenicilUum glaucum, showing mycelium and spores, (much enlarged). (Af- ter Laveran.) =?TCy^ Fig. 84.— Muoor mucedo. a. Mycelium and spores ; b, section of sporulatlng form ; c, showing dis- semination of spores (enlarged) . Fig. 85.— Rhizopus nigricans. should be familiar, since bread so affected is unfit for food. Chief among these growths is the Penicillium glaucum, which forms the green- ish patches so commonly observed on stale bread. Under the micro- scope the mould is seen to consist of ramifyiag filaments with characteristic brush-like extremities having a beaded appearance. These beaded extremi- ties are due to the arrangement of the spores of the penicillium. Many varieties of aspergiUus also find on bread a congenial field for then- develop- THE RATION. 251 Q ^ Fig. 86. — OMium aurantiacum. A, Mycelium ; B, spores (enlarged). ment. Among these may be mentioned A. flavus, which produces yel- low or light-brown spots ; A. glaucus, which gives rise to greenish blotches s imila r to those produced by PeniciUium glaucum, but distinguished from it by a more granular appearance ; A. niger, which gives rise to black granular spots; and finally, A. albus, which gives white granular patches. Under the microscope aspergUlus is readily distinguished from peniciUium, the filaments terminating in a bulbous enlarge- ment upon which the spores are disposed in a manner similar to that of a dandelion flower gone to seed. It is these spores which give to the spots produced by as- pergOlus their granular appear- ance. Three species of mucor are also found on mouldy bread. Of these, Mucor mucedo is the most common. It forms, on the surface of bread, spots which are variously white, gray or blackish. Under the microscope M. mucedo is seen to present a stem ending in a bulbous enlargement containing the spores and having a coUar- Kke projection around the bottom of this enlargement. When the spores are matured the membrane by which they are covered is detached and the spores fall on all sides. As these spores are black, the patch made by this growth appears white, gray or black according to the period of de- velopment. Mucor racemosus forms a yellowish blotch ; the filaments of this mould are shorter than in M. mucedo. Ehizopus nigricans, developing on bread, gives spots which are variously black or yellow. The growth is composed of short, ramifying filaments, terminating in bulbous ex- tremities having a mushroom like appearance when the spores are matured. The Oidium aurantiacum — a mould commonly found on bread — forms an efflorescence of a golden-yeUow or salmon color and having a nauseating odor. Under the microscope the growth shows a ramify- ing network on which appear globular bodies containing the spores. The latter have a characteristic discoidal ap- pearance. The Oidium lactis gives white patches of a s lim y appearance when developing on bread. Under the microscope the growth is seen to be made up of elongated cells placed end to end. fee Oidium albicans, an aHiSd species, has much the same appearance. Oidium auranti- acum has not infrequently been known to cause severe diarrhoea in persons who have consumed bread contaminated with this mould, and instances are given by Laveran in which similar symptoms have been produced by this agent in swine and horses. Viry mentions a case in which bread was covered with black and yellow mould forty-eight hours after baking, and this bread, fed to cavalry horses, produced paralysis. Ehizopus nigricans is believed to be especially dangerous. It is probable Fig. 87.— Oidium lactis. A, Ma- ture form; B, young lorm. 252 THEOEY AND PEACTICE OF MILITARY HYGIENE. that all moulds found on bread, through the changes which they induce and the toxins to which they may give rise, are more or less dangerous — the degree probably depending to a considerable extent upon the physical <;ondition of the oonsumer. From what has been said it is obvious that bread not immediately to be eaten should be stored in clean, dry and tight receptacles, preferably of metal or earthenware, and the latter sunned and sterilized at frequent intervals. The not uncommon practice in our service of keeping bread exposed to the air in damp, dark cellars or closets should be guarded against. As a general rule, bread for troops should not be issued earlier than twenty-four hours, nor later than forty-eight hours, after baking. Too fresh bread is unhealthful and the wastage is considerable, since many soldiers eat only the crust of such bread and reject the damp crumb. Hence, from an economical as well as sanitary standpoint, stale rather than iresh bread should be issued. In instances where the loaves have become too hard and dry they can be re-baked— the moisture being driven from the crust into the crumb by this procedure, and the bread thereby fresh- ened. An even better plan is to dip the loaves into water before re- baking. Such warmed-over bread, however, rapidly changes and must be eaten within twenty-four hours. It also lacks the elasticity of the fresh loaf and its interior crumbles as easily as before it was re-heated. Stale bread cut into thick sHces and toasted is thereby freshened; bread sour from an exfless of acid wOl become more edible through volatilization of the acid if cut into thin slices and toasted. As great cleanliness should be observed in handling bread as in makiag it. In some post bakeries it is stored in places where dust and dirt can get to it, or is handled by unclean persons and transported to the place of consumption in dirty receptacles. When fresh bread is to be shipped con- siderable distances to troops in the field, particularly if by wagon transpor- tation, the loaves of bread should preferably be wrapped in paraffin paper ; this serving the double purpose of keeping off dirt and preventing the bread from drying. For transportation, loaves should be placed on the side or end, not on the bottom. An army wagon will carry, with side-boards up, eighteen hundred rations of bread. Hard Bread. — Hard bread is made from unfermented or slightly fer- mented dough, from which most of the water is expelled during the process of baking. Its keeping powers are far superior to ordinary bread, for which it is temporarily a fair substitute under conditions where the latter cannot be obtained. Weight for weight it is much more nutritious than soft bread, ojj account of the small quantity of water present. It is, however, markedly deficient in fat, and the latter cannot be introduced into its com- position on account of the rancidity which early results. The average chemical composition of hard bread is as follows : Water, per cent. Protein, per cent. Fats, per cent. Carbohydrates, per cent. Fuel value per pound, Calories. 9.3 14.4 1.3 73.8 1,713 Hard bread should be of a light yeUow color, possess an agreeable taste and odor, be resonant when struck and dry to the touch, present no large THE EATION. 25S cavities and be well cooked without being burnt. The latter is important not only for the 'sake of driving off the water but also to increase digesti- bility through the conversion of a certain amount of starch into dextrin. Good hard bread should float and partially dissolve in water, and when placed in the mouth should thoroughly soften down. Other things being- equal, the best hard bread is that which becomes soonest softened when soaked in hot water. The bread best responding to this condition is one- slightly agrated, its substance being evenly pervaded with minute vacuola- tions. The density of the bread is lessened by this porosity, but the ad- vantage given above more than offsets the slight additional bulk, through the lessened danger of diarrhoea among the users. Such vacuolated hard bread is far more readily acted upon by the digestive juices than is a denser article. While salt improves the flavor of hard bread it increases- its liability to absorb water and impairs its keeping qualities — Whence this- substance should be added only in cases in which the hard bread is in- tended for immediate use. * Valuable as hard bread is for field use, it soon becomes difficult of di- gestion, and in the dry state, when improperly masticated, the sharp -irri- tating fragments are directly provocative of diairhoea. Further, troops early acquire a certain aversion to hard bread, and hence it should be issued only in instances where it cannot be avoided. Every effort should be made to insure that it is not used more than four or five days succes- sively. Hard bread should preferably be softened before use by steeping: in some fluid ; but soaking in water makes it pulpy and unsatisfactory and coffee, soup or similar liquids are not always obtainable. It is sometimes- softened in water and then fried in bacon fat. This renders it tough and indigestible, and such a method of preparation is to be strongly discour- aged. Weevils not infrequently make their appearance in hard bread, but can be destroyed by putting it into a bake oven and subjecting it to a temper- ature of 230° to 240° F. for the period of thirty minutes; or the hard bread may be spread out on a clean sheet or paulins and exposed to the hot sun for several hours. To prevent deterioration and protect against para- sites, bread of this character intended for the French army is put up only in the cold weather months and is packed in tins or wooden boxes having- the joints hermetically sealed with stout paper. When properly packed and stored, hard bread is good for about a year, but if exposed to a damp atmosphere it soon becomes mouldy. Hard bread was formerly put up in large rectangles, but this practice is now discontinued and it is issued only in cakes about one and^one-half inches square. Large biscuits appear to be more difficult to masticate than those of smaller size. Hard bread is now conveniently issued in one- pound stiff cartons. There is no waste, as formerly occurred to the large squares by crumbling when taken out of the original box. Pain de Guerre. — In this coimection note may be made of the "war bread " developed in the French ser-vice to remove the defects above noted as attaching to ordinary hard bread. At first, fresh issue bread was par- tially desiccated in the military bake-houses and then compressed, remain- ing fairly soft and suited for use in soup. It required, however, about a month to reduce the water in a loaf down to twelve or fourteen per cent.. 254 THEOEY AND PRACTICE OE MILITAEY HYGIENE. and when the residuum was moistened for use its edible qualities were regarded by troops as far from satisfactory. Private enterprise along these lines was also enlisted by the Government, but the result was a series of more or less complete failures. In December, 1892, the war office decided on making an extended trial of the compressed bread of Perrier, and after a two years' trial the reports received were fairly favorable. Before reach- ing a definite decision in the matter, however, the war office called upon all persons engaged in the baking trade to produce "a substance occupying very small space, but including, nevertheless, the whole of the qualities, nutritive and digestive, of ordinary bread." The required product was to keep good for a year without deterioration, its dimensions were to be such as to admit of its being readily packed in the soldier's valise, and its sub- stance was to be sufficiently resistant to withstand the shocks of ordinary transportation. The materials used were to consist exclusively of wheaten flour, leaven, water and salt. In shape, each piece was to be square or rectangular, with a due proportion of crust. The crumb was to be white and porous, and both the taste and smeU agreeable to the senses. Finally, the dryness must be perfect, there must be no crumbling and every loaf must swell out to the standard size within ten minutes after immersion in water at 50° C. The competition failed to produce a specimen superior to Perrier' s compressed bread, and the latter has, since 1895, been definitely adopted in lieu of hard bread in the French army. In appearance this bread somewhat resembles the biscuits for dog food now on the mar- ket. It takes up water more readily than ordinary hard bread, but, according to Laveran, remains in good condition after immersion in water and drying in the sun or by the fire. In soup, it is said to take up eight times its own weight of liquid. It has, however, the disadvantage of re- quiring about thirty minutes to soften completely in water, is more costly than ordinary bread and is not as palatable as fresh bread. It is believed by French authorities to be much superior to ordinary hard bread ; but this ©pinion, after due consideration of the merits of both articles, was not shared by the board of officers, in our own service, appointed for the pur- pose of devising an emergency ration. The process of manufacture of pain de guerre is a mUitary secret — ^but it is said to be a true fermented bread. Laveran states that a compressed aerated bread has been given careful trial in the Austrian army, as a result of which it has been formally in- cluded in the ration of that service. Fresh Vegetables. — These are always desirable to afford variety, for their own sake as food, to stimulate the appetite, to aid digestion and pre- vent con|tipation. They are most important in the prevention of scm-vy. Fresh vegetables were formerly not supplied to troops in the United States service, their addition to the ration beiag of comparatively recent date. In the earlier reports concerning the food of soldiers after the Civil War, it was commonly stated that, on the frontier, vegetables were scarce and correspondingly dear. Many complaints about the lack of vegetables were made — a deficiency thought to be in no small degree responsible for the high percentage of desertions occurring at that time — and numerous requests that potatoes and onions be added to the ration were made. A general scorbutic taint pervaded the troops during this period, and serious outbreaks of scurvy occurred at several of the frontier stations, notably in THE RATION. 255 the southwest. To relieve this condition at some of the posts, watercresses were planted in the neighboring creeks, gathered and eaten — and gardens were established where practicable. A few years later an improvement was observed; attributed to better transportation facilities, which enabled the company savings on bacon, flour and sugar to be expended on vege- tables. In many instances the soldiers themselves contributed toward the purchase of an additional supply of vegetables, often as much as a dollar a month per man. At present the vegetable component of the ration — be- sides beans, peas, rice and hominy — includes one hundred per cent, of fresh potatoes ; or eighty per cent, potatoes and twenty per cent, onions ; or seventy per cent, potatoes and thirty per cent, canned tomatoes, or other vegetables. No savings from these are purchased by the Government, and in time of peace, at established posts, the quantities allowed may be con- sidered as ample. Partly, however, on account of the small nutritive value of vegetables in proportion to bulk and weight, and partly on ac- count of their perishable nature, there will always be great difficulty in securing their actual issue during campaign, especially imder adverse cli- matic conditions — ^that is to say, there wiU be the greatest risk of failure just when they are most needed. But the recognition of their importance and the attempt to supply them constitute a true sanitary advance. The large amount of -vegetables used in continental armies is worthy of remark, and the taste for this class of food is doubtless increased by the foreign methods of cooking, which appear to be superior in many ways to our own. The hygienic examination of fresh vegetables is by no means as impor- tant as that of meats, but stiU should not be neglected. If they have become too old and woody, they are inferior in nutritive value and are imperfectly digested; stale vegetables are equally inferior in value and far from appe- tising. In general, they should be of good varieties, of reasonably krge and uniform size, fully matured, dry, free from cuts and dirt and in all respects of good quality and in good condition. Where vegetables are watered with sewage or drainage containing the ova of the animal parasites, these may find their way into man and un- dergo development; pathogenic bacteria may perhaps be introduced in the same way, and there is reason to believe that in this manner water- cress, growing in sewage-polluted streams, has been on several occasions the source of enteric fever outbreaks. In time of epidemic the fresh vege- tables used should be carefully selected and thoroughly cooked. The use of salads or vegetables in the raw state should be interdicted, as they are frequently contaminated with pathogenic micro-organisms through hand- ling or washing. In the southern states and in the tropics, vegetables rapidly deteriorate and imdergo decay. It is provided that such as have undergone deterioration shall be issued in increased quantities on the recommendation of a board of survey. In garrison or permanent camp, where conditions permit, gardens should invariably be cultivated by troops. These permit of a considerable saving of the ration through the vegetables which they furnish, and also supply a variety to the table which is much appreciated by the men. Certain stations, unfortunately, afford no facilities for gardens — and in the field gardening is, of course, impracticable. There is no work more cheer- 256 THEOEY AND PRACTICE OF MILITARY HYGIENE. fully performed by soldiers, or accruing more directly to their advantage, than the cultivation of vegetables for their own use. Dried or desiccated vegetables of excellent quality are now produced. As antiscorbutics they are inferior to fresh vegetables and the latter should always be supplied when possible. Dried vegetables may have a place in the ration duriag campaign, where transportation is limited and distances are great. To meet these indications they are supplied in various foreign services. Potatoes. — The white potato enters into the ration in the quantity of sixteen ounces daily ; a deduction from this allowance being made where canned tomatoes, onions or other fresh vegetables are also drawn. Pota- toes may be considered as occupying a place next in importance to the seeds of the cereals as a vegetable food, and are of particular value since their preparation may be largely varied and the system does not soon weary of their continued use. The juice of the potato is acid, due to the presence of a certain amoimt of free citric acid and the citrates of potas- sium, sodiiun and calcium, these rendering it particularly efficacious in the prevention of scurvy. As the amount of these salts is small, a con- siderable quantity of potatoes should be taken daily — at least ten or twelve oimces if no other vegetables are eaten. Being rich in starch but poor ia protein and fats the potato serves excellently to supplement the meat ration. The percentage of water is high, though not so much so as in turnips, cabbage and similar foods. When properly prepared, potatoes are very digestible as regards the carbohydrate element, ninety-three per cent, of this beiug digested. The protein, however, is less readily acted on, seventy-two per cent, only beiug digested. The waste in potatoes, as ordinarily prepared, is about twenty per cent. ; the average chemical composition of the edible portion being as follows : Water, per cent. Protein, per cent. Fats, per cent. Total carbohydrates, including fibre, per cent. Fuel value per pound. Calories. 78.9 u 0.1 18.0 380 Potatoes for army use should be of medium size. The very large ones are coarse and often hollow, while with very small ones, if peeled before cooking, the loss is considerable. The specific gravity of potatoes should be greater than that of brine containing 2.25 ounces of salt to the pint. Other things being equal, the greater their specific gravity the better their quality. They should be smooth, firm and free from worm holes and po- tato rot. On section they should cut with considerable resistance, being brittle rather than otherwise. If sprouting has occurred it can be detected by a close examination of the eye or by cutting just under the skin; the base of the eye enlarges inside as the potato sprouts, and such potatoes generally present a shrivelled appearance. Sprouted potatoes are unfit for use from the solanin which they contain. Viiy gives an instance in which poisoning was believed to have occurred from this substance ; and Coustan mentions a case in which one hundred and one soldiers were poisoned by eating sprouted potatoes. The symptoms produced were similar to those of belladonna poisoning. Fed to animals, these potatoes produced the same THE EATION. 257 symptoms. The quantity of starch present is an excellent indication of the cookiag qualities, and also whether, after cooking, the potato will be wet and soggy or dry and mealy. This may be estimated by bisecting the potato, perpendicularly to its long axis, with a sliarp knife. The condi- tion of the cut surfaces as to moisture should be observed, and where the moisture is sufficient to drip when the cut surfaces are held at an angle with the floor, the potato will be sogg3r and poor when cooked. If the two cut surfaces be placed together and rubbed agaiust each other with a cu-cular motion, the resulting white froth will be thick and tenacious if the potato be of good grade, and weak and watery if of inferior quality. On pressing the cut surfaces together, the degree of richness of the potato will be shown by the greater or less tenacity with which the parts cling to each other. The best test of quality, however, is given by cooking. Potatoes afFected with Phytophera infestans, or potato rot, are shown by the pres- ence of dark-brown spots, a peculiar flat. mouse-Like odor, and a reddish, marbled appearance on section. The nature of the fungus can be deter- mined by the microscope, if necessary. Potatoes are best stored in a cool, dry and well-ventilated place, and should not be exposed to the light more than is necessary. They should be frequently picked over and the spoiled tubers removed. Potatoes rapid- ly deteriorate in hot cHmates, and are best preserved under such conditions by spreading them out in a thin layer exposed to the air. As mentioned elsewhere, they may be preserved in the fresh state by slicing and packing in molasses. On a small scale, the boiling of potatoes will keep them for some time. Cold storage, several degrees above the freezing-point, is of course the best method of preservation. Onions. — These may be drawn by the soldier in the amoimt of 3.2 ounces daily and are much appreciated as a savory and wholesome com- ponent of the ration, both as a food and condiment. The waste in prepar- ing onions is ordinarily about ten per cent. ; the average chemical composi- tion of the edible portion being as follows : Water, per cent. Protein, per cent. Fats, per cent. Total carbohydrates, including fibre, per cent. Fuel value per pound. Calories. 87.6 1.6 0.3 9.9 235 One of the special qualities of the onion is the presence of a pungent, volatile oil, to which its characteristic taste and odor are largely due. Onions for army use should be firm and the outside leaves crisp. If they have sprouted, the fact can be determined by cutting them open. Dishonest dealers frequently cut off the sprouts and twist the outside leaf over the cut so as to conceal it. Onions should be free from defects, dry and solid. An onion pulled before it has thoroughly matured will have more or less moisture on the outside and be soft in spots. Overgrown onions are not desirable, being generally less firm and of poorer flavor than those of average size. This vegetable will stand a greater degree of cold without injury than wUl potatoes; if frozen, those thawed out slowly in a dark place are not much injured for immediate use. The white variety pos- sesses the sweetest and mildest flavor, but the better keeping qualities 17 258 THEORY AND PEACTICE OF MILITARY HYGIENE. of the yellow and red varieties render them far preferable for storage pur- poses. Onions are very perishable and are best kept in a single layer on narrow slatted shelves, arranged one above the other at convenient dis- tances. Tomatoes. — Canned tomatoes are wisely included in both the service and travel rations — their issue m the latter being allowed after four days' continuous travel. In the former ration the quantity is 4.8 ounces, while iu the latter the daily allowance is 16 ounces. The tomato is a better antiscorbutic than the potato. Its acid is malic, which it holds free at about .3 per cent, and about as much in combination with bases. The tomato is excessively watery, and, as ordinarily supplied, the solid constit- uents of the canned article, after straining, vary from fifteen to fifty per cent. It would seem as if some definite standard should be required ia this respect; for where the fluids are in high proportion the Government pays for the purchase and transportation of water and the soldier is large- ly defrauded of an article with which it was intended he should be well supplied. The practice of accepting the lowest bid, and requiring no definite standard for the goods, is naturally fatal to quality and forces articles of the best character out of competition. Under the ordinary proc- esses of canning a considerable number of cans undergo fermentation and are spoiled. It has recently been found that this fermentation can be almost wholly prevented by processing at a high temperature with super- heated steam, and without deterioration in quality of the contents. Ee- processed cans are always of poor quality. They are those in which leaks are detected after processing, and are known by the presence of an undue amount of solder along the seams. Canned tomatoes stand extremes of climate without apparent deterioration. The average chemical composition of canned tomatoes is as follows : Water, per cent. Protein, per cent. rats, per cent. Total carbohydrates, Including fibre, per cent. Fuel value per pound. Calories. 94.0 \2 0.3 4.0 105 Other Vegetables. — Besides potatoes, canned tomatoes and onions, the legal ration provides for the issue of "4.8 ounces of other fresh vege- tables not canned, when they can be obtained in the vicinity of the post or transported in a wholesome condition from a distance." As a matter of fact, advantage is rarely taken of this provision within the limits of the United States, and such other vegetables as are used by troops are either derived from post gardens or are purchased from the company funds. At stations where transportation facilities are poor or the facilities for keeping fresh vegetables are inadequate, particularly in the tropics, it may frequently be necessary to rely upon vegetables grown in the vicinity. For the convenience of sanitary officers, therefore, the averages of analyses of the vegetables not specifically named in the ration, but liable to enter to some extent into the subsistence of troops, are here inserted. In preparing fresh vegetables for the table a waste of fifteen to twenty per cent, should ordinarily be expected. THE EATION. 259 Article. Water, Protein, Fats, per cent. per cent. per cent. 58.9 9.4 0.6 66.5 7.1 .7 89.2 2.3 .3 87.5 1.6 .1 91.5 1.6 .3 88,2 1.1 .4 92.3 1.8 .5 75.4 3.1 1.1 89.5 2.3 3.4 94.7 1.2 .3 83.0 1.6 .5 69.0 1.8 .7 91.8 1.3 .1 88.8 1.7 .5 93.3 2.1 .3 94.3 .9 .4 89.6 1.3 .2 71.86 1.0 .2 75.3 1.3 0.6 Carbohyarates, Including fibre, per cent. Fuel value per pound, Calories. Beans, butter, green, edible portion Beans, lima, fresli, edible portion . . Beans, string, fresk, edible portion. Bees, fresh, t edible portion Cabbage; fresh, edible portion Carrots, edible portion Cauliflower, edible portion Corn, green, edible portion Greens, beet, cooked Lettuce Parsnips, edible portion Sweet potatoes, edible portion Kadishes, edible portion Sauerkraut Spinach, fresh Tomatoes, fresh Turnips, edible portion Yams, edible portion Ripe bananas, edible portion. ' Used as a vegetable in the tropics 39.1 22.0 7.4 9.7 5.6 9.3 4.7 19.7 3.2 2.9 13.5 24.4 5.8 3.8. 3.2 3.9 8.1 35.05 32.0 740 570 195 215 145 210 140 470 345 90 300 570 135 135 110 105 185 500 460 Cooking of Fresh Vegetables. — ^Vegetables shrink in bulk about ten per cent, in cooking, besides which a certain proportion of the nutri- tive principles are lost in the process. The latter is a matter of far greater importance than is commonly appreciated. Vegetables contain a large amount of water, dissolved in which are con- siderable amounts of soluble inorganic compounds or salts, and more or less soluble organic substances — such as sugar and soluble protein compounds. The solid matter of vegetables consists largely of microscopic cells filled with starch grains. The walls of these cells are composed of cellulose or woody fibre, which resists the action of the digestive juices ; and it is for this reason that the raw vegetable is, as a rule, unfit for food. When, however, heat is applied, the starch grains absorb the water from the juice, swell up and finally burst the cell walls, so that the texture of the vege- table becomes soft and the nutrients are easily attacked by the digestive juices. Heat is usually applied by boiling, frying or baking, the first being the method most commonly used. During the process of boUing vegetables there is, of course, more or less opportunity for nutrients soluble in water to be dissolved out and lost. Indeed, much of this matter is aheady in a state of solution in the juices. The nutrients which would be liable to suffer such loss are, as mentioned above, some of the protein compounds, some of the mineral constituents, such as salts of potassium and sodium, and especially the sugars. The starch would suffer no appreciable loss in this way, owing to, its insolubility. It might, however, be removed me- chanically from the soft cooked vegetables under certain conditions. Of the protein compounds, those which are of the most value to the body are coagulated and thus rendered msoluble before the boiling-point is reached, behaving like the white of an egg tmder similar conditions. The loss of the more valuable portion of the protein would, therefore, take place before the water became sufficiently hot to cause coagulation. Some nitrogenous 260 THEOEY AND PEACTICE OF MILITARY HYGIENE. Fig. 88.— Cells of a Eaw Potato, with Starch Grains in Natural Condition. substances are, however, soluble in water at all temperatures, and would thus be liable to loss during the entire process of boiling. Sugar is pres- ent in considerable quantity in some vegetables, and in such cases the loss of nutrients may amount to a considera- ble fraction of the original nutritive value. With reference to potatoes, it was recently found by Snyder and Bryant that, when peeled and soaked for several hours before boiling, the loss amoimted to fifty -two per cent, of the total nitrogenous matter and thirty- eight per cent, of the mineral sub- stances ; when the potatoes were peeled and put into cold water, which was then brought to the boiling-point as soon as possible, the loss was much less, amounting to about sixteen per cent, of the nitrogenous matter and nineteen per cent, of the mineral sub- stances. Potatoes peeled and placed at once in boiling water lost but half as much nitrogenous matter as in the preceding case, although the loss of mineral salts was practically the same; when potatoes were cooked with their skins on there was • but a trifling loss of material, either nitro- genous or miaeral. The character of the water, whether hard or soft, had but little influence on the result. In none of the experiments was there any appreciable loss of starch other than that resulting from the abrasion of the peeled potatoes during the latter part of boiling, when they had become soft and mealy. With reference to the mineral matters dis- solved out it should be remembered that these salts, while not nutrients in the sense in which this term is frequently used, are nevertheless im- portant in nutrition. They are of especial value because of the potassium compounds which they contain, and are apparently necessary for health. The conclusions drawn from these ex- periments may be briefly summarized as follows : In order to obtain the highest food value, potatoes should not be peeled before cooking. When the potatoes are peeled be- fore cooking, the least loss is sustained by putting them directly into hot water and boiUng as rapidly as possible. Even then the loss is very con- siderable. AVitli reference to the effect upon boiling of roots, such as carrots, beets and parsnips, investigation upon the first named vegetable, cut into wedge- FiG. 89.— Cells of a Thoroughly Boiled Potato. THE EATION. 261 shaped pieces averaging about four inches in length, showed a total loss in the smaller pieces amounting to thirty per cent, of the total food material ; or more specifically, to forty-two per cent, of the nitrogenous matter, twenty-six per cent, of the sugar and forty-seven per cent, of the mineral constituents. It appeared to make comparatively little difference whether the water used was hard or soft, or if it were hot or cold at the start. The medium-siaed pieces lost the same amount of sugar as the small pieces, but less nitrogen and less mineral matter. As was expected, the least loss occurred when large-sized pieces we're used ; but even then it amounted to one-fifth of the total nutrients, one-fifth of the nitrogenous matter, one- sixth of the sugar and over one-fourth of the mineral constituents. When it is considered that carrots really contain as much water as is found in mUk, it is readily seen that with the loss of from one-fifth to one-third of the whole nutritive matter there is no great food value left in the cooked vegetable. The loss of sugar during the boiling of carrots is equivalent to nearly one pound of sugar in a bushel of the vegetable. It appears, there- fore, that in order to retain the greatest amount of nutrients in the cooking of vegetable roots, the pieces should be large rather than small; the boning should be rapid, in order to give less time for the solvent action of the water to act upon the food ingredients ; as little water as possible should be used, and unless the matter extracted be used as food, instead of being thrown away, the loss of twenty to thirty per cent. — or even more — of the total food value may be pre- vented. Taking cabbage as a type of pot herbs in which the leafy portion is the part eaten, sim- ilar experiments showed that the kind of water (hard or soft) has more effect on the loss of nutrients than the temperature of the water when the cabbage is placed therein. In any case the loss of nutrients was found to be very great, amounting to one-third the total nutrients when soft water was used, and two-fifths when the water was hard. The loss of the more valuable albuminoids was comparatively small, although the total loss of nitrogenous matter ranged from thirty-two to forty-six per cent, of the total. More than half the mineral salts were removed, and from twenty-eight to forty-two per cent, of the carbohydrates. In a cabbage weighing three pounds there are but four ounces of dry matter; the remaining two and three-fourths pounds is water. Of this four oxmces, from one and one-fourth to one and three-fourth ounces may be lost during the oooking, leaving as much nutriment available from a three pound cab- bage as woiild be contained in about two heaping tablespoonfuls of sugar. Fig. 90.— The Composltioii of the Cabbage and the Loss ol Nutrients when Boiled, a. Starch, sugar, flhre, fat, etc.; fo, non-albuminoid nitrogenous matter ; c, albuminoid ni- trogenous matter ; d, mineral matter. The hatched portion represents the loss. 262 THEOEY AND PEACTICE OF MILITAEY HYGIENE. This loss seems to be unavoidable unless the cabbage is cooked in such a manner that the water iu which it is boiled is also used. This is fre- quently the case when it is cooked with corned beef. In the Eussian army the water in which cabbage is boiled is invariably utilized in the preparation ofc soup, thus securing aU the nutritive constituents of the vegetable for consumption by the soldier — and the same is true of the other vegetables used in the foreign services, ia which soups and stews are the usual methods employed in the preparation of the ration. Of the other methods of preparation, frying presents the objections already advanced with reference to the cooking of meats, as well as entail- ing a considerable waste through peeling. As already noted, stewing insures the use of all the nutritive principles of the vegetable to the purposes for which it was provided. Eoasting in the ashes, a common method of pre- paring potatoes in the field, is wasteful, since carbonization of a consider- able proportion of the vegetable is the, rule. Baking is excellent, but care should be taken to select potatoes of the same size throughout, to insure evenness of cooking. The waste and loss by baking is small. DRIED VEGETABLE COMPONENTS. Beans and Peas. — These belong to the Leguminosae, and in respect of their dietetic properties are broadly distinguished from other vegetable foods by their large amount of nitrogenous substance, called legumin or vege- table casein, which is probably largely derived from certain globulins and albumoses present in these seeds. The advantages of peas and beans as articles of diet are their richness in legumin and salts, especially those of potash and lime. Their disadvantages lie in their great indigestibility, and poorness in fat and sodium chloride. Eubner has shown that from about twenty-one to thirty per cent, of the nitrogen of peas passes out un- digested in the faeces, as compared with thirteeen and fourteen per cent, of the nitrogen of white bread and about seventeen per cent, of black bread. The existence of sulphur frequently causes flatus from the production of hydrogen sulphide. Still, they are most valuable articles of food and ought to be much used during campaign, as they constitute an excellent addition to bacon, bread and the cereals. Both men and beasts can be nourished on them alone for some time, and in fact, added to rice, they form a staple food for large populations of India and other tropical countries. When fat is added, as in the common method of preparing baked beans, they form an article of diet well calculated to fulfil all the nutritive re- quirements of the organism. The daily allowance of either beans or peas is 2.4 ounces, a quantity which appears to be amply sufficient. As too often cooked in the military service, beans are tough and indi- gestible and favor the occurrence of intestinal disorders. There is nothing more true — at least for the field, where time for their proper preparation is often wanting — ^than the old saying that "beans kOl more men than bul- lets." This criticism, however, relates only to the improperly prepared article. To prepare beans, they should be soaked in warm water about twelve hours and then be boiled until they are tender, which will require about two or three hours more. No amount of boiling will soften old beans ; such should be soaked twenty-four hours and then crushed and stewed. THE RATION. 263 It should not be forgotten that neither beans nor peas can be properly cooked in hard water. Where such is the only supply at hand it should be corrected before use, according to the method given elsewhere. The following table shows the average chemical composition of issue beans : Water, per cent. Protein, per cent. Fats, per cent. Total carbohydrates, including fibre, per cent. Fuel value per pound, Calories. 13.3 32.3 1.8 59.1 1,605 The small white bean is used in our army, it possessing many qualities which render it specially adapted to the military service. It resists wee- vils and moisture best and stands transportation well. While small beans are preferable, this quality is not so important as uniformity in si^e, so as to insure evenness of cooking. New beans, if dry, are to be preferred, and can generally be told by their being soft when bitten through. The tendency of beans is to absorb moisture, and if sacked in a damp condition they are liable to become musty. They should be removed from the sacks and exposed to the sun from time to time, this not only keeping them dry- but destroying weevils. Good split peas should be free from huUs or skins and_be of a bright orange color. When brown in color, it indicates scorching during the pro- cess of kOn-drying. Ordinarily, one part of the dry pea equals, by weight, about four parts of the fresh pea in proteids and carbohydrates. Their richness in nitrogen makes them theoretically valuable as substitutes for meat ; but as a matter of fact they are not relished to any extent by troops, who ordinarily make use of them only in soups. Peas are much inferior to beans as a military food — ^the latter partaking of the nature of a national dish — and can well be dropped from the ration except for field service, when they should be issued in the form of pea-meal to supply the deficiency of protein in the bacon ration. The average chemical composi- tion of dried peas is as follows : Water, per cent. Protein, per cent. Fats, per cent. Total carbohydrates. Including fibre, per cent. Fuel value per pound. Calories. 10.8 34.1 1.1 61.5 1,655 Lentils are thought to possess laxative qualities and be more digestible than beans or peas. They are included in the rations of several foreign armies, including that of France. They are not a popular article of diet in this' country and are rarely used as food by civiliaris, a fact which at once shows them to be undesirable for our military service. Rice. As an article of diet, rice has the advantage of possessing an extremely digestible starch grain. It is, however, poorer than wheat in protein, fat and salts, and is essentially a carbohydrate food. Alone, it cannot be made into bread, but it is much used in France in connection with wheat flour to make the very white bread which is in request in that country. It is said that during the siege of Santiago the Spanish troops were subsisted on bread largely composed of rice. While rice constitutes so great a proportion of the food of the human race, especially in warm 264 THEOEY AND PEACTICE OE MILITARY HYGIENE. climates, it is comparatively little employed in the United States. It is included in the ration in the quantity of 1.6 ounces, but is not especially popular with troops ; a fact apparently due to the usually improper methods of preparation employed in our service, it being ordiuarily insufficiently cooked or else reduced to a paste. Eice should not be cooked by boHiag, but be steamed until tender. When boiled, it yields to the water a con- siderable part of its nitrogenous and mineral constituents, ia which it is already naturally deficient. This objection does not apply to the prepara- tion of rice for soups, in which aU its extracted matters are ultimately consumed by the soldier. The characteristics of good rice are semi-transparency, freedom from grit, dust or huUs, and few broken or dead-white grains. Its average chemical composition is as follows : Water, per cent. Protein, per cent. Fats, per cent. Total carbohydrates, inclurtinpr nbre, per cent. Fuel value per pound. Calories. 13.4 7.8 0.4 79.0 1,630. A good, clean, fresh-milled head rice is required for the army. Old rice has a yellow appearance, while the fresh-milled is clean and white. Mustiness is detected by the smeU. Storage should be ia a cool, dry place, the greatest danger being from weevils and moisture. Eice is the most important constituent of the Japanese army ration, being issued in the amount of thirty-six ounces daily per man, and constitutes the emer- gency ration in the same service. It also enters into the rations of the German, Austrian and Italian armies. Efforts should be made to popu- larise its use in our service by giving more attention to the best methods of its preparation. Hominy. — This is included in the ration in the proportion of 1.6 ounces. It is an article of food much used in the southern states, but it is not popular among the residents of the northern part of this country, from which latter region the military establishment is largely recruited. It is but little used by troops, and there would seem to be no valid reason why hominy should be retained in the ration as long as cornmeal is also issued. The average chemical composition of hominy is as follows : Water, per cent. Protein, per cent. Fats, per cent. Total carbohydrates, including fibre, per cent. Fuel value per pound, Calorlea. 11.8 8.3 0.6 79.0 1,650 Hominy should be stored in a cool, dry place. It is Mkely to harbor weevils in summer and to become musty in warm, moist weather. Oatmeal. — It would be much to the advantage of troops if hominy were replaced by rolled oatmeal in the ration. The latter is a substance rich in nitrogenous matter and is an excellent food for soldiers at aU times. As porridge, which consists simply of the meal well boiled, it admits of various nutritive combinations, and while it lacks adhesiveness for making large loaves it can be readily made into small flat cakes which are very palatable. It is a valuable addition to animal and vegetable broths, and THE RATION. 265 its issue in the form of grael, to guards or troops performing heavy fatigue, is much to be recommended. To cook rolled oatmeal it should be mixed with boiling water and allowed to stand and simmer, without stirring, for twenty minutes. This is ;fractically the only cereal food which can be used with satisfactory results without further cooking. When no fire is available, if mixed with cold water, with a little salt or sugar, and allowed to stand for one or two hours, it makes a palatable, wholesome and nutritious food and drink combined. For this purpose the rolled article is preferable to the steel-cut oatmeal, as the former is already partially cooked by the steaming process requhed in its preparation. The average chemical composition of steel-cut oatmeal and rolled oatmeal is as follows : Fig. 91.— Eice Weevil, Calandrla oryza. (o). Beetle; (J)), larva. (Uucb enlarged.) Article. Water, per cent. Protein, per cent. Fats, per cent. Carbohydrates, including fibre, per cent. Fuel value per pound. Calories. Steel-cut oatmeal 7.3 7.7 16.1 16.7 7.2 7.3 67.5 66.3 1,860 1,850 Oatmeal should be stored in a cool, dry place and not near articles that emit odors. It deteriorates with age and, therefore, the supply should be frequently renewed. Eolled oatmeal appears to keep better than the steel-cut article. Cornmeal. — This, on account of deficiency in gluten, is not adapted to making raised bread without the admixture of wheat or rye flour. It can readily be made into cakes, or be boiled and fried ; containing, as it does, nearly as much protein as wheat flour and much more fat, it stands in a high position as regards alimentary value for the military service. It is a common article of diet in the southern portion of this coimtry, and when weU. prepared is usually much liked by troops. Its use in our service should be encouraged. Through the mechanical irritation of the intestine by its particles it prevents constipation. This same quality, however, operates against its use during outbreaks of diarrhoea and dysentery. Corn- meal, if kept too long on hand, or if not properly stored or cared for, is liable to become sour. It is also frequently injured by worms, these being of comparatively large size and of repulsive .appearance. The average chemical composition of granular and unbolted commeal is as follows : Granular commeal. . Unbolted commeal . Water, per cent. 13.5 10.3 Protein, per cent. 9.3 7.5 Fats, per cent. 1.9 4.3 Carbohydrates, including fibre, per cent. 75.4 65.9 Fuel value per pound. Calories. 1,655 1,545 266 THEOEY AND PEACTICE OF MILITARY HYGIENE. Dried Fruits. — These are a recent and valuable addition to the food allowance of the soldier, each ten rations iacluding three each of dried apples and apricots and four of prunes. The daily allowance is two ounces. Dried fruits have a special value iu coimection with the field ration, since they act as correctives to a diet of bacon, hard tack and coffee in prevent- ing constipation. They are also antiscorbutics, and*although scurvy could probably never occur in garrison with present food allowances, there is naturally a tendency to it in the field with the above limited diet. Dried fruits, if properly prepared, may be expected to keep a year. They are light and are uninjured by freezing, and when cooked a small quantity of the dried article will make an amount sufficient for many men. The aver- age chemical composition of the dried fruits issued is as follows : Apples Apricots Prunes (whole) Water, per cent. 28.1 29.4 19.0 Protein, per cent. 1.6 4.7 1.8 Fats, per cent. 2.2 1.0 Carbohydrates, including fibre, per cent. 66.1 62.5 62.2 Fuel value per pound, Calories. 1,350 1,290 1,190 Dried fruits should be free from dirt, sticks and worms, and should contain a considerable proportion of sugar. They should not be hard or shrivelled, nor should the taste be musty. Prunes should have a glossy appearance, this disappearing with age. Old and stale prunes are fre- quently dipped in hot sugar and water; a process which restores the gloss but not the softness and smoothness of the freshly packed fruit. As prunes are not pitted, and as the pits are often as large in the smallest as in the largest prunes, the latter are obviously preferable. Good prunes have a thin, soft, pliable skin and abundance of meat of a rich, delicately sweet flavor. Fresh fruit, which may be noted in this connection, does not enter into the ration of the soldier; but much is nevertheless consumed by troops, either as individual purchases or provided from company funds. It is ordinarily a valuable addition to the dietary ; bananas and grapes being the most important from the standpoint of nutrition, although all are grate- ful for the vegetable acids which they contain. While sound, ripe fruit which has not been handled is undoubtedly harmless, that which is un- ripe, decayed or contaminated by uncleanly handling or improper storage is always unwholesome. To avoid outbreaks of intestinal disorders the in- spection of fruits offered for sale to troops, particularly by hucksters in the vicinity of camps, should be rigid. When intestinal disease is prevalent among troops, the sale of fruit, from unlmown sources and by irresponsible parties, should be prohibited in camp or garrison. Fresh fruit, when sup- plied from the company fund, should preferably be eaten by the men only after cooking, since by this way the dangers attaching to possibly unripe or contaminated fruit are avoided. THE EATION. 267 THE SUGAR, COFFEE AND CONDIMENT COMPONENTS. Sugar. — The authorized daily allowance of sugar is two and two-fifths ounces, a quantity which for ordinary use appears to be barely sufficient. Brown or issue sugar contains more water than the white, the amount varying from 4 per cent, in the better kinds to 10 per cent, in the coarse varieties. Its color is due to invert sugar, of which there is 4 or 5 per cent, present. The average chemical analysis of brown sugar shows 95 per cent, carbohydrates, with a fuel value , of 1,765 Calories per pound; white sugar contains 100 per cent, of carbohydrates and has a fuel value of 1,860 Calories per pound. The whiter the sample, the less usually is the percentage of water. The unpurified sugars contain nitro- genous matters which decompose, and a sort of fermentation often occurs. Mites are often found in such sugar, while fungi are very frequently present. When of good quality, sugar should be more or less white, crys- talline, not evidently moist to the touch, and should dissolve entirely in water — or leave merely small fragments, which, on examination with the microscope, will often be found to be bits of cane. In this country sugar is rarely adulterated, its present low price protecting it from such frauds. Out of five hundred samples of sugar lately examined by the Department of Agriculture, not one was found to be adulterated. Sugar being com- pletely soluble in water, the presence of adulterants of an earthy nature is readUy determined from the residue left after such solution. It should not be forgotten that cane sugar may be converted into dex- trose, a much less sweet substance, as a result of the change known as in- version, which takes place when cane sugar is made to unite chemically with water, as by boiling with an acid. Cane sugar in this case splits up into a mixtiu'e of dextrose and levulose, known as invert sugar. Company cooks should be instructed that more sugar is necessary in sweetening acid fruits if it is heated with them from the first than if it be added when the cooking is completed. This is because some of the cane sugar, acted on by the heat and acid, has been changed to other bodies which are less sweet. The great value of sugar in increasing the ability to perform work and lessening or delaying fatigue has but recently been recognised. Much work on this subject has been lately done, and the results aU point to the efficiency of sugar in this respect. Harley found that when nine ounces of sugar were added to a meagre diet, the gain in muscle power was consider- able. The effect, though felt one-half hour after eating, was at its height in two hours. Very interesting also was the effect of sugar in delaying the natural coming on of fatigue, which had been found to occur between 5 and 7 p.m. If three or four ounces of sugar were taken a short time before this hour, fatigue did not appear and work went on as usual. Schumberg, experimenting on this subject for the Prussian war office, says : " The practical conclusion to be drawn is that sugar in small doses is weU adapted to help men to perform extraordinary muscular labor." If the sugar is to be taken in solid form he recommends chocolate as the best 268 THEOEY AND PEACTICE OF MILITAEY HYGIENE. medium. The application of these results to the food of soldiers who may be called upon for extraordinary exertion in marching or fighting is very evident; and in 1898 a practical test as to the value of sugar was made with soldiers of the German army during the autumn mancEuvers, the observation extending over thirty-eight days. A number of men were given ten lumps (70 gm. or about one-sixth pound) of sugar daily, and were compared in various ways with men performiag the same amount of work in marching and drilling, but whose food contained little or no sugar. The results were in every way to the advantage of the men using sugar. The sugar was relished during the whole time. On long marches it appeased hunger and mitigated thirst ; a feeling of refreshment followed which helped the tired man on his way, and none of the soldiers allowed sugar were at any time overcome by exhaustion. It was found that both their pulse-rate and breathing were less affected by exertion than was the case with the men consuming no sugar. On the basis of these results the medical officer making the investigation recommended that the sugar ration for soldiers be raised to 60 gm. daily, and that it be furnished as sugar for coffee and ia sweetened food, preserves or honey. The uifluence of sugar on muscle exhaustion was further investigated in 1899 by Prantner and Stowasser. Before performing muscular work, 30 gm. of grape sugar were administered in weak tea. In control experiments an amount of dulcin equalling the sugar in sweetness was taken. The investigators did not know whether they had consumed sugar or dulcin. More work was performed when sugar was consumed than in the other cases. When sugar was added to a diet which sufficed for nitrogenous equilibrium, the amount of nitrogen excreted in the urine was diminished. In the opinion of these observers sugar is useful as a muscle food for those who have a single mus- cular task to perform, rather than for those who are engaged in constant, though severe, manual labor. Within the past two years, according to Abel, sugar has been much used in the training diet of athletes, not only apparently increasing muscular power and endurance but preventing stale- ness from over-training. During the recent war in South Africa the Brit- ish soldier received a ration of jam, four ounces three times weekly, which was said to be much appreciated. In view of these facts it is certainly much to be regretted that sugar has been omitted from the established emergency ration, since the evidence is conclusive in showing the special service rendered by sugar under just the conditions in which this special ration would be employed. There can be no doubt that about three ounces of sugar, combined with chocolate, would be a valuable addition to the emergency ration. Molasses and Cane Syrup. — These are each issued, in lieu of sugar, ill the proportion of two gaUons per hundred rations. They are not much liked by troops and are rarely drawn. As a substitute for sugar the ration of molasses or cane syrup is quite inferior. Analysis gives to molasses a composition made up of 25.1 per cent, water, 2.4 per cent, nitrogenous matter (probably not protein), and 69.3 per cent, carbohydrates; the fuel value per pound is 1,290 Calories. The chemical composition of cane syrup varies little from that of molasses. Saccharin. — In this place it is convenient to mention saccharin — orthobenzoic sulphinide — ^which has appeared in the trade as a white in- THE EATION. 269 odorous powder, three hundred times as sweet as cane sugar. Pure sac- charin is soluble in water, one part in two hundred and sixty, and has a faintly acid reaction ; but lately an alkaline salt has been introduced which is more readily dissolved. Its flavor is slightly aromatic and its after- taste irritating only when the powder itself, or a concentrated solution, is tasted ; dilute solutions have a purely sweet flavor. As one part of sac- charin is sufl&cient to give five hundred parts of starch sugar the same sweetening power as an equal part of cane sugar, it is likely that adultera- tions of this character wiU. be made. The detection of saccharin may be effected by extracting the dried substance with anhydrous ether. If the evaporated residue have a sweet taste saccharin is present, since aU sugars and glycerin are insoluble in ether. According to the experiments of aU observers, saccharin is non-poisonous, even in continuously large doses. Since, however, it has no nutritive or stimulant value, its substitution for a carbohydrate in the ration is quite inadvisable and against the interests of the service. The alleged antiseptic properties of saccharin have, as a matter of fact, no practical importance. Coffee. — The allowance of coffee in the ration is 'one and three-fifths ounces when in the green state, and one and seven twenty-fifths ounces when roasted ; this difference representing the average loss of water during roasting. This allowance appears to be sufficient, especially since soldiers generally prefer to use their coffee in an extremely weak infusion. Its employment in this way should be encouraged, as it insures the use of a sterile drink. In winter the heat given out by steaming hot coffee is valuable and permits of a certain quantity of food being used for pur- poses of energy, which otherwise would be devoted to the maintenance of body temperature. In summer, coffee supplies in a safe form the fluid necessary in the production of perspiration, and when carried in the canteen on the march it proves an efficient substitute for water and is valuable for its directly stimulating properties. As an article of the ration it is indispensable, and in our service is much preferred by the men to tea. When supplied in the fresh bean, coffee keeps well and is not sub- jected to adulteration except in rare cases. Hence it is in this form that it should be purchased for army use. Sometimes coffee contains black, mouldy and worm-eaten kernels, and such samples should obviously be re- jected. In the ground and roasted state it is frequently adulterated with chicory, the dried and powdered root of the wild endive; this adulteration is not injurious to health and the flavor of coffee sophisticated in this manner is even preferred by some. In the Belgian army it is even inten- tionally mixed, in equal parts, with the coffee to be issued. The Govern- ment, however, should receive the pure article for which it pays a full price, and the .soldier is entitled to the full benefit of the stimulant quali- ties — so valuable in the field — present in coffee and wanting in chicory. A number of tests have been proposed for the detection of the latter sub- stance; of these the fact that when thrown into water, chicory rapidly sinks and colors the liquid brown, while coffee floats and does not leave any color, may be used to advantage by the sanitary officer. If additional evidence be required, the microscope may be used, the characteristic cells and dotted ducts of chicory being at once apparent, while the long cells of 270 THEOEY AND PEACTICE OF MILITARY HYGIENE. the testa of the coffee berry are marked and the interior contains an irregu- lar areolar tissue containing light or dark yellow angular masses and oil globules. The appearance of coffee is not necessarily a reliable index of its quality, and a sample should always be roasted, ground and made into an infusion. The latter should be tested for odor as soon as practicable and by taste as soon as cool enough for the purpose. After standing a little while, the odor and taste should again be noted. This test is best made comparative by making a control experiment at the same time with coffee of known good quality. Care should be taken that the coffee beans in a sample are of the same size ; since, in roastiag, the small grains may be carbonized before the larger ones become sufficiently parched. The extent to which coffee is roast- ed materially influences the amount of matter susceptible of extraction. When roasted to a reddish-brown color and subjected to boiling water, Pavy found that twenty-five per cent, could be extracted — as against nineteen per cent, when the roast- ing was carried on to a chestnut- brown color. AU coffees improve with age and should be at least one year old before being used. They require dry, well-ventilated stor- age, and, as they readily absorb odors, should not be placed in proximity to articles possessing a strong odor. When ground, coffee does not keep well, especially in hot, moist climates. Ground coffee should always be put up in tight containers. When coffee has been long roasted and is hence a bit stale, it is said that it can be freshened and much improved in character by heating before grinding. In the field the disadvantages of coffee are its bulk and the ease with which the roasted and ground berry is lost from the haversack and parts with its aromatic constituents. The issue of the green berry in the field, as was the case during the siege of Santiago, is often of almost no utility ; since where the soldier is provided merely with his mess kit the proper roasting and grinding of the berries is practically beyond his powers. As prepared in our service, coffee is often not an infusion but an over- boiled decoction, and sometimes contains considerable charcoal due to care- lessness in roasting. Some company cooks habitually boil their coffee and leave it on the fire for several hours, a practice destructive to its good qualities. In cool climates it is of advantage to moisten the gi'ound coffee and let it stand over night before infusing. In this way the full quality of the berry is said to be extracted to best advantage. For the preparation of coffee an excellent form of apparatus is used in the French army which should be adopted in our service. By its use it is said to be practically impossible to prepare coffee of any but excellent quality. As shown in the accompanying illustration, the water in the lower reservoir of the ap- FiG. 92.— Section of Coffee Bean. Enlarged. Ing long cells of the testa In the berry. Notter and ilrth.) Show- (Alter THE EATION. 271 ^r ■^ -i^i f IHI Fig. 93.— Coffee Percolator. paratus is forced up through the central pipe and sprayed over the ground coffee resting on the upper perforated sheK; it then trickles through the coffee into the upper reservoir and is returned to the lower res- ervoir . — to re- place the water forced out b y ebullition — by a pipe discharging near the bottom. Willie boiling is maintained i n the apparatus the percolation through the ground coffee is thus continuous. By this method the necessity of clarifying with egg shells, fish skin, cold water or other means is avoided. It is sometimes of advantage, with ordinary pots, to place the ground coffee in a thin muslin bag before adding to the water. Tea. — ^As issued to troops, tea leaves are curled; but they assume their original appearance when placed in hot water, and show their character- istic shape and structure. The border of the leaf is serrated nearly, though not quite, to the stalk ; the primary veins run out from the mid-rib nearly to the border and then turn in, so that a distinct space is left between them and the border. The leaf may vary in point of size and shape, being sometimes broader and sometimes long and nar- row. In general, the larger the leaf the weaker wiU be the infusion and the less the value. A knowledge of the structure of the tea leaf is of importance, since a common method of adulteration consists in the addi- tion of the leaves of the aloe and willow, which have a superficial resemblance to those of the tea plant. Such adulteration naturally alters the flavor of the tea. A common method of falsification, also, consists in the addition of old or exhausted tea leaves, these being given a natural color by artificial means and then dried. Such coloration, which is produced by several methods, gives rise to a dirty scum which forms on the surface of the infusion and often imparts a somewhat greasy appearance and feeling to the leaves. If an infusion of such tea be strained through cloth, some of the coloring matter will be retained on the fabric. The total soluble matters obtain- FiG. 94. — Tea Leaf. (After Notter and Firth.) 272 THEORY AND PEACTICE OF MILITARY HYGIENE. able from tea are a ready and convenient index of its quality. In general, with a good tea a weighed quantity infused with an excess of distilled water should yield, on evaporation of the iafusion, a residue possessing thirty per cent, of the weight of the quantity of the tea used. Sand and magnetic oxide of iron are sometimes added to tea to increase its weight. These substances can be readily detected by the microscope. Like coffee, the quality of tea can often best be determined by its preparation. The buyers of tea appear to depend especially on the taste and smell of the in- fusion. In general, tea fit for army use should not be too much broken up or mixed with dirt. Spread out, the leaves should not be all large, thick, dark and old, but some should be small and young. In the best tea there will always be a good deal of the stalk and some remains of the flower. In old tea much of the ethereal oil has evaporated and the characteristic aroma is less marked. The allowance of tea, either green or black, is fixed at eight twenty- fifths of an ounce. This quantity is quite sufficient to meet the needs of our service. As compared with coffee, tea has practically the same physio- logical action but its flavor is by no means as acceptable to most soldiers. Tea lends itself admirably to campaign uses, its weight being about one- sixth that of coffee and it having the further advantage of small bulk. A water-proof covering is necessary for its carriage in the field, and for this purpose tea is much used in the German service in small tablets, wrapped iu paraffined paper. When improperly made or allowed to stand, tea be- comes bitter from the tannin which it contaias ; and the latter substance also attacks iron. When carried in the canteen this action is marked. Tea is best made in scrupulously clean vessels with no exposed iron, and should be prepared by pouring boiling water on the leaves and letting the whole steep for a few minutes in a covered utensil. If hard water must be used this fault should first be corrected by the method given elsewhere. Besides having the sanitary advantage of boiled water, tea masks many of the offensive qualities of water containing suspended and decomposing organic matters and its use for this special purpose may at times be of ad- vantage. Tea is generally preferred to coffee by Arctic explorers, and by hunters and trappers ra the northwest. It is much used in the Russian army, practically replacing coffee in certain mUitary districts, and is also largely employed in the British army. In the expedition against the Ashantis in 1876 the experiment was successfully tried of substituting tea for the spirit ration allowed the British soldier. In the French service tea is used only in the colonies ; the soldiers, according to Laveran, ordi- narily regarding it more as a medicament than a beverage. Chocolate. — This is a substance which, whUe too costly for garrison use, may with advantage be supplied, in the proportion of two or three ounces, in the field ration — serving as required either as a food or beverage. It contains about thirteen per cent, of protein, fifty per cent, of fat and thirty per cent, of carbohydrates, and has a force value per poimd of nearly three thousand Calories, or almost three times that of fresh beef. Its pala- tabnity and keeping qualities are admirable and it is very compact and portable, thus fulfilling all the requirements of a military food. Unlike tea and coffee, its stimulant properties are smaU. THE RATION. 273 - Chocolate is largely adulterated. When of good quality it should be compact, brittle and of a reddish-brown color. It should break ia the bar under only a moderate strain and the fracture should be clean and show a fine grain. When worked into a paste it should be perfectly homogeneous. It should melt easily in the mouth, leaving no residuum, and should com- pletely dissolve in milk or water. Chocolate forms the basis of part of the English emergency ration ; and as cocoa, which is chocolate with a considerable proportion of the fat removed, it is commonly used in the same army. Large shipments of chocolate were recently made to the British troops operating against the Boers in South Africa. Chocolate is not a common beverage in this country, and for long-continued use would undoubtedly become somewhat distasteful to troops and inferior to coffee. For field use, however, it has everything to comcmend it, and its great pala- tabHity would render it at once a pleasant as well as nutritively valuable component of the ration. Salt. — The use of salt in the org&iism is extremely important; about an ounce of saline substances being necessary for the proper maintenance of nutrition. The chlorides generally keep in solution the globulins of the blood and other fluids, while at the same time they are the sources of the hydrochloric acid of the gastric juice and materially aid in the solution of albumen. The sodium salts are especially necessary in a vegetable diet to compensate for the quantity of potash salts contained in vegetable material. The complete withholding of ordinary salt from the food leads to rapid disease and even death. Its partial deprivation caused much suffering among the French troops during the siege of Metz, inducing a peculiar lassitude and muscular weakness. Sodium chloride is a constituent of all animal tissues, and this fact was formerly utilized by the Indians, who, in the absence of salt, were accustomed to retain the water in which meat had been boiled and use it in the preparation of other meat. Considerable sodium chloride is dissolved out of meat by boiling, and water repeatedly used for this purpose ultimately acquires a a distinctly saline taste. The culinary use of salt to render food more palatable is generally in excess of the requirements of the system, and in such excess it must be considered as a condiment. The failing of nearly aU cooks is to use salt and pepper in excessive quantity. These articles must always be within reach that each man may flavor his food to his taste, and cooks should be in- structed to use the minimum amount of seasoning. The present allowance of salt, sixteen twenty-flfths of an ounce — together with the salt present in the bacon and pork ration — amply suffices for the needs of the sol- dier. In character, salt should be clean and free from foreign matter. Dis- solved, it should leave no earthy residue. The cheapness of salt offers no inducement for its adulteration. Pepper. — Black pepper is issued in the proportion of four ounces per one hundred rations. This quantity appears to be sufficient, as it is a sub- stance by no means necessary to the welfare of the organism and is em- ployed only to give a zest to food. It owes its value as a condiment to the aromatic oil which it contains. This oil is antiseptic in quality and undoubtedly has a certain influence in retarding acid fermentation in the 18 274 THEORY AND PRACTICE OE MILITARY HYGIENE. digestive tract. Pepper also promotes the flow of digestive juices and stimulates peristaltic action of the intestines. The microscopic characters of pepper are somewhat complicated; there being a husk composed of four or five layers of cells and a central portion. The cortex has extremely elongated cells, placed vertically and provided with a central cavity, from which lines radiate toward the circumference. Then come strata of angular cells, which toward the interior are larger^and are filled with oil. The third layer is composed of woody fibre and spiral cells. The fourth layer is made ifp of large ceUs, which toward the interior become smaller and of a deep red color ; these contaia most of the essential oil of the pepper. The central part of the berry is composed of large an- gular cells, about twice as long as broad. Steeped in water, some of these cells become yeUow while others remain colorless. Pepper is one of the most adulterated articles on the market. Liuseed, mustard husks, wheat and pea flour and ground rice are often added ; the character of these substan- ces can be determined by the microscope. Pepper is also largely adulterated with husks, ground cocoa- nut shell and mineral sub- stances. The latter can be separated by shaking with chloroform. The active priuciples of pepper reduce Fehling's solution, and no pure pepper should give less than fifty per cent, of reducing sugar on the asli- free substance ; cocoanut shell adulterations usually give about half that quan- tity. If the powder be covered with pure hydrochloric acid the true pepper grains become in- tensely yeUow, and from these the other substances can be picked out. Vinegar. — ^The vegetable acids are directly represented in the ration by vinegar, the allowance being one gallon per hundred rations. This quantity, though not large, is rarely consumed, and can with advantage be diminished by one-half and replaced by an equivalent quantity of pickled vegetables, such as cucumbers, onions or tomatoes. Vinegar is a valuable antiscorbutic and its use in any form should be encouraged. For army use cider vinegar is preferable, and this should contain about five per cent, of acetic acid. The quantity of this acid present may be readily determined by the sanitary officer by taking the specific gravity, the variation ranging as follows : Fig. 95.— Section ol Pepper Berry, Enlarged, and Firth.) (After Notter Speciflc gravity. Per cent, of acetic acid. Specific gravity. Per cent, of acetic acid. Specific gravity. Per cent, of acetic acid. Speciflc gravity. Per cent, of acetic acid. 1,001 1,002 1 3 1,004 1,005 3 4 1,007 1,008 5 6 1,010 1,013 7 8 THE KATION. 275 In addition to sophistication with water, vinegar is not infrequently adulterated with mineral and pyroligneous acids. Usually sulphuric acid is added ; this must be determined with care, as the addition of water may have introduced sulphates. The test consists in adding hydrochloric acid and barium chloride to the vinegar; the resultiag sulphate of barium, dried, weighed and multiplied by .412 gives the weight of the sulphuric acid. The occurrence of hydrochloric acid is readily determined by adding a solu- tion of silver nitrate to the vinegar, with resulting formation of white silver chloride. Nitric acid is shown by the development of a red color on the addition of a few drops of strong sulphuric acid and brucine. Pyroligneous acid may be recognized by distilling the vinegar and re-distOling the dis- tillate; the residue has the odor of pyroligneous acid. Vinegar is also adulterated by many other substances, but these wOl rarely come to the attention of the military sanitarian. In the examination of foods by the Massachusetts Board of Health fifty-seven per cent, of aU specimens of vinegar examined were found to be adulterated. In many vinegars, espe- cially the weaker kinds, the minute vinegar eels, AnguiUula oxyphila, wiE be found in great numbers. Beyond rendering the vinegar somewhat disgusting in appearance they are not known to exert any prejudicial effect. They are readily destroyed by heating to the bojling-point. IV. EUEBaENCT OB RESERVE RATIONS. General Considerations. — Celerity of movement is a matter of prime importance in modern warfare. Sufficient facilities for the proper trans- portation of supplies being often not available, or if available serving merely to hamper and delay troops, the question of the concentration of the ration to such a degree as to enable the soldier to carry a sufficient supply of food, and thus operate without transportation, for limited periods, at once presents itself. To this end much thought and research have been de- voted — especially since the results attributed to the use of " Erbswurst " during the Franco-Prussian War — ^but the preparation of an emergency food, in all respects satisfactory, can scarcely be considered to have as yet been accomplished. Much, however, has been done, and a vast number of preparations of greater or less value for military use, some of them con- stituting the so-called " iron rations " of various armies, are now on the market. Among these may be mentioned the various meat, vegetable and pea sausages, the meat powders, meat biscuits, concentrated soups, meat extracts and different compound rations made up of two or more preserved food-stuffs. As to the special qualities which should be present in the emergency ration, it should be noted that such a ration must often be carried by the soldier for continued periods, and, as the military conditions under which its employment would be authorized are those in which mobility is of prime importance, the first objective in its construction is to provide the greatest food value in the least possible bulk and weight. At the same time a too radical departure from the accustomed food of the soldier cannot be made, lest the digestive system be deranged by the sudden 276 THEOKY AND PRACTICE OP MILITAEY HYGIENE. change — and this at a time when the physical efficiency of each man is of the highest importance. The keeping qualities required of an emergency ration place further limitation on its composition ; and a certain variety should be possible, not only in material but in manner of preparation, as sameness soon becomes distasteful. It must be palatable, since if it be disliked by troops it will be wasted and its theoretical value as food largely nullified. To this end a oertaia amount of condiments should enter into its composition ; and since the occasion in which its use is authorized wUl usually be accompanied by great exertion and fatigue, it should preferably possess not only nutritive but somewhat stimulant properties. It is essential that a fair proportion of the ration should be in a solid form, so that a certain amount of mastication is required and an undigested residue is left to keep the intestines operative through the mechanical stimulus which it provides. It is also necessary that the emergency ration should be a cooked, dry preparation, which can quickly be made iato a soup or stew — or which, in the face of the enemy or the absence of fire, may be eaten cold, with or without the admixture of water. The latter quality is one too often disregarded. The addition of water to such condensed food has the advantage of giving an increased bulk which distends the stomach and gives a feeling of satisfaction, while at the same time it promotes digestion. The emergency ration should as far as possi- ble be eaten hot, since heated foods are comforting and stimulating iu con- ditions of exhaustion and there is also an actual economy of food where its temperature has been raised. This, though so slight as to be ordiaarily neglected, becomes of importance where foods are restricted in quantity. An emergency ration need not necessarily contain the several nutritive principles in the quantities and proportion necessary for the maintenance of life and health during an indefinite period. It should, however, possess a relatively high force-value and contain an amount of reparative mate- rial sufficient to prevent undue waste in the body tissues during the short time in which such a ration should be employed. Any deficiency in the carbohydrates — which should be the nutritive principle to be first reduced ■ — may be to a certain extent counterbalanced by the higher potential value of the fatty element present, not only in the ration but within the organ- ism of the consumer. The fatty principle, however, cannot be advanta- geously increased beyond a certain point, nor can it take the place of pro- teid in the repair of the , muscular system ; and the latter, if called on to excess for the nitrogen necessary for elimination, ultimately becomes enfeebled. While reduction in bullc and weight is desirable, there is a limit, how- ever, to which this decrease can be carried out; and scarcely more than the removal of an excess of water and a considerable part of the indigestible material is possible. In practice, the dehydration and compression com- monly produced for the sake of concentration appear to affect the alimen- tary value of the substances concerned by influencing their digestibility and readiness of assimilation. This is especially observed in compressed and desiccated vegetable material — and a sudden change to this class of diet win exercise considerable influence on the production of hunger, in- digestion and intestinal troubles. With regard to the use of foods con- centrated beyond a certain point, it must be admitted that the stomach is THE KATION. 277 constructed with a certain capacity for food which cannot be disregarded in favor of any chemical formula which human tugenuity can create or theoretical reasoning devise. Each of the varied and subtle processes of digestion must necessarily adapt themselves to the construction and func- tions of an organ which has a vital as well as a chemical duty to perform. No prepared or concentrated food can relieve the stomach of any or all of its activities in that gradual conversion of a legitimate quantity and qual- ity of food which constitutes the normal and perfect digestion; and the stomach must be properly distended with food of a sufficiently bulky char- acter, else its most important function is hampered. In concentrated and chemically prepared foods, sufficient importance does not seem to be at- tached to those portions which are normally passed ofi' with the excretions. Such as are undigested and indigestible are generally regarded as a direct loss, yet all these fulfil very important purposes. Something more is re- quired than complete digestibility and power of absorption in order to gain a full physical effect and retain health in a normal condition. Eegarding the total weight of an emergency ration, it has been stated by Parkes that no great loss of body-weight or impairment of health may be expected to occur with a minimum daily allowance of eleven ounces of water-free food and a maximum time of one week. This statement may be considered as approximately correct, provided the food is properly pro- portioned as to its nutritive principles, troops are fuUy fed before being placed on such a restricted ration, and are subsequently allowed rest and a generous dietary for the replenishment of the systemic losses. Officers should appreciate that, while supplying a certain amount of force, concen- trated foods are ordinarily not sufficient to repair but merely retard tissue waste, and that, like high explosives, there are strict limits to their field of usefulness. A practical objection to prepared foods, as seen in many of the commercial emergency foods, is the ease with which adulteration and fraud can be practised. The quality of food can be readily determined if seen in the natural state, but when the article is ground up and mixed with other material no such safeguard exists. This objection, however, is somewhat lessened by the fact that prepared foods are intended for occa- sional use only — and it may probably be made to disappear under a rigor- ous system of inspection and analysis. In most foreign services one or more emergency or reserve rations is habitually carried in peace or war in the equipment of the soldier — he being thus accustomed to its appearance and weight. This would seem to entail a useless expenditure of energy, and the far better plan for our own service consists in issuing these rations to troops only when there is reason to believe that they may soon be required. The portions in which the emergency ration is issued should never be larger than the allowance for one day ; since a package, once broken, soon deteriorates in quality and becomes unfit for use. The various components, especially the meat, should be kept separate. The emergency ration should not be used until aU other sources of supply fail, and then only on orders from high author- ity. If possible, it should not be used alone but should be supplemented by any other articles of food available. Once used, it should be replaced as soon as possible if the circumstances indicate that it may be again re- quired. Its maintenance while in the care of the soldier should be insured 278 THEOEY AND PEACTICE OF MILITARY HYGIENE. by frequent inspection, and its unauthorized use, should be punished by disciplinary measures and a proper stoppage against the pay of the of- fender. On the whole, not more than three or four of these rations should ever be issued at any one time, since they are at best but make- shifts and by their continued use the organism suffers. Ordinarily an unforeseen emergency, where the use of such foods becomes desirable, wiU. last for but a few hours. The United States Army Emergency Ration. — This ration was elaborated by a board of ojEficerg several years since, acting largely on the recommendations of similar and subordinate boards convened for the same purpose in each military department. Its composition and nutritive value is as follows : Articles. Quantity in ounces. Protein, grams. Fats, grams. Carbohyarates, grams. Fuel value, Calories. Hard bread 16- 10 4 2 .5 .64 .04 .5 70.76 24.94 24.94 5.89 218.14 2.25 332.94 ' 59.84 1712 Bacon 2,030 Pea-meal 368 Coffee, roasted and ground, with four grains of saccharin Or tea, with four grains of sac- Salt Pepper Tobacco Total 33.68 120.64 236.28 392.78 4,110 The force-value of this ration is high and the available nitrogen is sufficient for the needs of hard labor. Divided in half, it practically fur- nishes the subsistence diet of physiologists. The components of this ration are put up in small individual packages ; the bacon being wrapped in tough paraf&n paper, the hard bread in grease-proof coverings and the pea-meal in cylindrical packages. The other articles are put up in small water-proof packets. It is officially enjoined that this ration shall be re- sorted to only on occasions arising in active operations when the use of the regular ration may be impracticable; that although it may be used in half allowance, it will not be so used except in case of overruKng necessity and never for a longer period than ten days ; also that not more than five of these rations are to be carried on the person at one time. ^ This emergency ration was subjected to a practical trial in the field, in 1897, by a troop of cavalry; the command having been given a preliminary march of two days on full rations. The men were then weighed and pro- ceeded on a ten days' march, averaging about twenty-one miles daily. The route was through a totally uninhabited country where no food could be obtained from outside sources. Five full emergency rations were issued to each man at the start, and these were made to do for the fuU ten days. Careful records kept by Smart showed that during the ten days there was an average loss of weight amounting to 2.935 pounds per man; but the loss was not evenly distributed, some men maintainiug their original weight while five men even gained in weight. The losses in weight were greater among the younger soldiers and those of heavier build. The muscular THE EATION. 279 strength of the command, as shown by the dynamometer, increased an average of twenty -four pounds per man. A control experiment was made at the same time by an officer and nine men, who were allowed to eat aU they desired of the regular established ration. This detachment marched parallel to the route of the larger command at a distance of about ten miles. Of this smaller detachment the average loss in weight amounted to 1.35 pounds per man; the average strength, as shown by the dynamometer, increased by 32.8 pounds. From the above practical test of its value the sufficiency of half portions of the emergency ration, during the period of ten days, may be regarded as established. This ration has the important advantage of containiag practically no articles except those to the use of which the soldier is habituated, and which are always available or kept on hand by the Subsistence Department. It contains no compound prepared foods and its proper quality is readily assured. It requires no special machinery or plant for its manufacture and is also comparatively light. On the other hand, it possesses certain posi- tive disadvantages. It is somewhat heavier than the emergency rations used in foreign armies and the bulk of the hard bread makes the carriage of five fall rations on the person of the infantryman a matter of some difficulty. Further, only one article of this ration — ^the hard bread^ — can be eaten without further preparation by fire, and this may be a serious defect under many conditions. As aheady noted, sugar possesses a high value in the prevention of fatigue and the creation of energy. It should by all means replace saccharin, in the emergency ration, preferably in the amount of two or three ounces. Sweetened chocolate might also be issued alternatively as well as the tea and coffee. Since half portions of the author- ized emergency ration are shown to be sufficient for subsistence, it is diffi- cult to understand why this ration should remain in its present quantity, which is practically a double allowance. It would certainly appear to be of advantage to make the individual ration smaller. For the above reason it would seem that this ration, while excellent in nearly all respects, might justly be regarded rather as a reserve than an emergency ration in the sense that this term is applied abroad. As yet none of these rations have been issued and used in actual service. Since the chief value of this ration as regards energy is due to the high proportion of fat it contains, it is obvious that the method of prepara- tion exerts a marked effect upon the quantity of nutritive material con- sumed by the soldier. When food is abundant such a loss may be of no particular importance ;. but it is intended that every portion of an emergency food shall be devoted to purposes of nutrition and no provision is made for wastage. When the bacon is fried to a crisp, the meat is reduced about two-thirds in weight and the fat fried out is ordinarily lost. If softened hard bread be fried in the melted bacon fat a greater proportion is saved, but the resulting combination is indigestible. The best method of pre- paring the bacon undoubtedly consists in chopping it into small frag- ments and boiling it in the pea soup. In this way there is no wastage. With the idea of avoiding the several practical faults of the emergency ration just descijbed, a board of officers has recently devoted much time and effort toward devising a combination of foods more adopted to emer- gency purposes. Their proposed ration, at the present writing, is being 280 THEORY AND PRACTICE OE MILITARY HYGIENE. given a trial by troops in the west. It is understood to be composed of two parts. The first consists of parched wheat, mixed with beef which has previously been dried in thin strips and then crushed into small frag- ments. A little seasoning is added. The mixture is very palatable and makes an excellent soup; though it may be eaten without any cooking, if necessary. The second portion of the ration consists of sweetened choco- late, which may obviously be used as either a food or beverage. This ra- tion, which it is proposed to pack in an oval tin having two compartments, wUl furnish 127 gm. of protein and has a fuel- value of about eighteen hundred Calories. The amount of fat present is small, and the fuel-value of the ration, for its weight and bulk, suffers greatly thereby. Much of the protein is of vegetable origin and is hence less readily digestible. It does not appear that this ration possesses any special virtues over a num- ber of excellent concentrated foods now on the market. In its proximate composition and fuel- value — as is shown by a subsequent table — it is very much inferior to the pemmican and cocoa-paste emergency ration of the British army, to some of the Bovril emergency foods and to certain other preparations. Emergency Rations of Foreign Armies. — Experiments are still in progress in the British army with reference to a suitable emergency ration. Until 1896, this ration merely consisted of a couple of ordinary cooked rations. Eecently a compressed vegetable ration of imknown composi- tion, used with compressed tinned beef, has been tried. Bovril cartridges have also been tested, and it is said that a considerable number of the so- called "Standard Emergency Ration," put up by a firm in this country, have been used by the British troops in South Africa. The custom is to allow makers and inventors of prepared military foods to furnish samples of their products for trial, and officers and men are also authorized to make experimental use of such articles at their own expense. Pemmican has been much used by British troops in the field in India, Africa and else- where. This is a preparation of beef, with fat and salt. It is supplied in flattened tins about four and one-half inches long, weighing eight ounces. The method of manufacture is a trade secret. It can be eaten without any preparation, or can be made into beef tea, hash or soup by boiling with vegetables. It is said that it will keep sound for years, even after free exposure to the air. As shown by analysis, this prep- aration gives sufficient salts, protein and fats for emergency use. It con- taias no carbohydrates, and these are supplied in another part of the offi- cial emergency ration. This second portion consists of cocoa and honey, in another compartment of the can containing the pemmican. The net weight of the pemmican and cocoa paste is about nine ounces. With this ration, eight ounces of hard bread are usually issued for use in an emer- gency. According to Woodruff, the French soldier when in the field carries two days' reserve rations, which he is not allowed to consume except by order from higher authority. The components of this ration and their approximate weights in ounces are as follows : Hard bread 43 ounces. Rice 7 " Preserved meat 17 " THE RATION. 281 Condensed soup If ounces. Salt 1^ " Sugar 2 " Roasted coffee If " The hard bread has presumably been replaced by the new war bread, but whether in the same amount is not known. The above weighs four pounds, ten oimces; the daily allowance berag one-half of this quantity. This is an unusually generous diet for emergency use. As in most foreign rations, the fats appear to be notably deficient. These rations are put up in two small sacks, so that they may be kept separate from the other rations. As the smallest tin of meat issued holds four field rations, one of these boxes is given to every other man. The German foot-soldier carries an emergency ration sufficient for three days. This is not drawn upon except in cases of urgent necessity or when it can be at once replaced by a fresh supply. The cavalry soldier carries but one day's extra rations. The infantry emergency ration is as follows: Hard bread 17.5 ounces. Preserved meat 7 " Or bacon 6 " Bice 4.5 Or meal 6.75 " Coffee 875 ounce Salt 875 " The above weighs two pounds, four ounces. The daily amount is but twelve ounces of water-free food, which is about twenty per cent, less than in our own emergency ration. It is undoubtedly a meagre diet when taken by itself, but it is intended for use dmring short periods only and is probably also regarded as a base to which the food usually to be obtained in a densely populated country, like Europe, could be added. It is said that a modification of this ration, containing two pounds of hard bread, one povind of preserved meat and one pound of tinned preserved peas, the latter containing considerable- fat, is now being tried. The Austrian army has several emergency rations. , Of these, one is stated by Viry to contain 400 gm. of compressed bread, 200 gm. of preserved meat and vegetables, 25 gm. of salt, and coffee and sugar in tablets. An- other emergency ration used in the Austrian service is composed as follows : Hard bread 17-6 ounces. Preserved meat 7 Preserved soup 1-3 Salt 3 " Each of these rations is obviously of extremely low nutritive value and suitable for use during brief periods only. Switzerland has an emergency consisting of 8.75 ounces (250 gm.) preserved meat, 50 biscuits (5 gm. each), weighmg 8.75 ounces (250 gm.), and 3.5 ounces (100 gm.) of compressed pea or bean soup-powder. The biscuits are in a cloth bag, the soup powder is in parchment paper and the meat in a tin. This weighs somewhat more than twenty-one ounces without the packages. Two days' rations, weighing forty-two ounces, are carried on the person, being packed in a water-proof ticking bag. Two days' extra supply is also carried in wagons. The above is a very convenient and 282 THEORY AND PEACTICE OP MILITARY HYGIENE. relatively nutritious ration; but its weight is greater than our own emer- gency ration, which it somewhat resembles except in the matter of fats. The Italian " iron " or emergency ration consists merely of fourteen ounces of hard bread and eight ounces of tinned meat. Two of these rations are carried on the person. The hard bread is issued in large squares, weighing about seven ounces each. The regulations governing the use of this ration, like those of certain other foreign armies, provide that troops shall subsist upon it at certain periods during the year, so as to prevent the rations kept on hand for an emergency from becoming stale and uneatable. In the Eussian army a variety of prepared meat-cakes, according to Notter and Firth, are issued for emergency use. They consist mainly of finely powdered meat mixed with barley or peas, or oatmeal, or cabbage, or potatoes and mushrooms. Their use in the Eussian service is highly extolled, although they are admitted to be difficult of digestion. The daily allowance is about twenty -five ounces. The soldiers of the Japanese army, in the late war with China, carried an emergency ration of rice in a cylin- • drical tin case strapped to the knapsack. The emergency ration of the Portuguese army is said by Viry to be composed of sausage, codfish, bacon, rice, biscuit, salt and coffee. The Spanish army, so far as known, has no reserve or emergency ration. Special Preserved or Concentrated Foods. — A large number of spe- cially prepared breads are now on the market, most of which are in the nature of bread from which the water has been largely removed by heat or pressure. The desiccated bread of Balland is made by exposure to heat for a varying period. On wetting, it is said to take up about seven times its weight of water, while hard jDread takes up only an equal weight. This bread is made of flour containing a high proportion of gluten. The com- pressed bread of Bernard has the shape of an ordinary cracker and a slightly brown exterior. The water is almost entirely driven off by heat during the process of manufacture, which is secret. It absorbs water readily. The cracker-bread (pain biscuite) of FaiU.^ is a similar preparation, which when wet muclf resembles ordinary bread. The process of manufacture is also secret. Laignel's bread is ordinary bread from which the water is removed by hydraulic pressure. Much water flows out, but when removed from the , apparatus the bread still feels moist. In a day or two, however, it becomes as hard as stone — and after a year's time will still be found good and palat- able. Placed in water, it slowly swells. The pain de guerre of the French army has already been mentioned. In general, the various prepared breads may, in case of necessity, be eaten from the hand. Ordinarily, however, they should be softened in water, as they are otherwise masti- cated with difficulty. Many of them are excellent articles for field use. Allusion may here be made to the so-called "pinole," a preparation made by mixing three parts of parched groimd Indian corn and one part of sugar. This preparation has been used in our service, particiilarly in the south- west, and has been found to have many good qualities. Among the preserved meats, pemmican — mentioned elsewhere — takes a high place through its nutritive qualities. It is digestible and wholesome, but is only fairly palatable. The unattractive appearance and insapidity of dried meat afford objections to its use. As prepared in this country. THE EATION. 283 dried beef is usually cured with salt. It is thus far too salty for contia- ued use, and is also said to contain a high proportion of moisture. Canned meat is useful for the field, but is too heavy for emergency rations. A board of officers, however, some time siuce, reported favorably on canned roast or boiled beef as a substitute for bacon iu the emergency ration, and small cans of preserved meat are used for emergency purposes in several foreign armies. The preservation of meats by various methods is discussed elsewhere. It may, however, be stated that it is extremely difiicult to find a preserved meat, of small bulk, which has a pleasant taste and con- tains a proper proportion of nutrient elements. Many attempts have been made to utilize meat powders in the military rations of various nations, and they were used as long ago as the Crimean War in the French army. Meat powders keep well and are highly nutri- tious, digestible and wholesome. Such powders are stated by Notter and Firth to possess generally about four times the nutritive value of fresh meat with bone. They possess, however, a disagreeable taste and odor. These faults have been corrected to a certain extent in the meat powder prepared by Eousseau, which was reported to the French Government to be "unchangeable, odorless and tasteless, without diminution of nutritive principles. It is capable of being preserved for many years in a simple waterproof envelope. One part of this powder is equal to several parts of fresh meat." Among the various compound preparations made of meat powders, the proportions generally adopted are : Meat powder, 25 per cent. ; powdered vegetables, 50 per cent.; fat, 10 per cent.; salt, 8 per cent.; condiments, 2 per cent. A dried food which was favorably considered in the French service, about ten years ago, was compounded of the following ingredients : Powdered Articles. Grams. Meat 20.00 Peas, lentils, rice and beans 80.00 Pot herbs 5.00 Beef tat 18.00 Hog's lard 7.00 Salt 9.00 Pepper 04 Total 139.04 The food value of the above amount was said to be as follows : Protein, grams. Fats, grams. Carbohydrates, grams. Fuel value. Calories. 33.73 26.30 44.08 573 In addition to their use in soups, meat powders are also made up into cakes with various flours and powdered desiccated vegetables. Hoffman's meat powder is a superior article, and has been shown to contain seventy- three per cent, of albumen, seven of salts, ten of water and one of hydro- chloric acid. Hoffman's meat cakes are agreeable, portable and easily prepared ; but if used for any considerable period the appetite fails and the digestion is impaired. They have been tried in our own army in connec- tion with hard bread, but were not received with sufficient favor to warrant 284 THEORY AND PRACTICE OF MILITARY HYGIENE. their regular issue. Johnson's and Erdmann's meat powders are similar to other preparations of this kind. The majority of meat biscuits now in the market are, as a rule, nothing more than meat powders mixed with flour and water ; owing to the extreme heat to which they are exposed in baking, the meat in them is usually rendered valueless. Some combina- tions, however, appear excellent. Port, in 1886, brought a meat biscuit to the attention of the French authorities which was found to have many good points. Later, Scheurer-Kestner prepared a biscuit made extremely digestible by the addition of pepsin. In Germany, a biscuit is made by Schill which contains defibrinated blood instead of water. This food is highly assimilable. Another food is "Courousa," made by Jacques, which has been tried in the Russian army. The meat cakes used in the emer- gency ration of the last named service have been mentioned elsewhere. A preparation made by Grouvel was tried in the French army several years ago, eleven ounces being said to afi'ord sufficient nutriment for a day's allowance. Its composition was roughly 20 parts of beef powder, 48 parts of pea flour, 20 parts of fat and 12 parts of condiment. A recent prepara- tion tested in the German army consists of the "Kraft-zwieback," composed of wheat flour, fat and powdered meat, with a proportion of salt varying to taste. This is said to have given very satisfactory results in practice. "After the exclusive use of this food during fourteen days, devoted to field manceuArres, without any untoward results, the men of an infantry regiment were able, on the fifteenth day, to acccomplish a march of 52 kilometers." The price of meat powders is somewhat high, and during the past few years their popularity has waned through recognition of the facility with which meat of bad character could be used in their composition. The concentrated soups and meat extracts date from the introduction of Liebig's well-known preparation. Numerous articles of this kind are now in the market — notably those of Armour, Wyeth, Brand, Kemmerich and others — which exist chiefly in the form of fluid meats, essences and extracts. Meat extract, formerly held a high place in popular estimation, particularly in Germany, but it has been conclusively demonstrated that their nutritive value is practically nil. Indeed, these extracts are not free from danger when used for any length of time, and it has been shown that animals die more quickly when placed on an exclusive diet of Liebig's ex- tract than do those given no food whatever. These preparations, however, are not quite devoid of alimentary value ; but they act as stimulants, food regulators and digestive agents rather than as nitrogenous food-stufl's. It would be a fatal mistake to use these extracts, deluded by their portability, with the idea that they contain considerable reparative materials in small compass; they are essentially alimentary aids and not true foods. If used solely in that sense, they can be turned to very good account as stimulants after very great exertion or exposure. When canned roast or boiled beef is used, the addition of beef extract to the stew wiU greatly in- crease its palatabUity, since it contains the substances on which the flavor of meat depends. Beef extract is now put up in the form of capsules. This is a convenient method of carriage, but when a liquid extract is used the moisture dissolves the gelatin and the capsule ultimately coUapses. Quite recently beef extracts have been prepared, both in solid and liquid form, which contain a considerable proportion of albuminous material, and THE EATION. 285 hence are true nutrients. Among these may be mentioned Wyeth's beef juice and BischofFs "Toril "—a solid extract. The latter would probably prove of value ia connection with emergency foods. Among new concentrated food products, which may possess a value in connection with the emergency ration, may be mentioned tropon, aleuron, nutrose, somatose, eucaseia and caseSn. These are all patented articles, a fact which seriously impairs their availability for military use. Among these, tropon appears to be of the most value. It is a light brown, almost tasteless powder of sandy consistency, made of raw vegetable and animal materials. It is not perishable, is not hygroscopic and is not soluble in water, but is readily soluble and digested in the gastric juice. It is said to contain 90.44 per cent, of albumen — and weight for weight to contain five times as much digestible albumen as fresh beef. The analysis of this substance, as given in a subsequent table, shows its high nutritive value. Tropon has recently been given a practical trial in the German army by a detachment of one officer and twenty-five men. Special rations, wrapped in water-proof paper, were supplied by the manufacturers of tropon. Each man received three yeUow packets containing one day's rations of tropon rusks and tropon chocolate, which he carried in his cooking utensils ; also a round white packet containing two days' rations of the solid materials for tropon bean and pea soup, which he carried in his bread sack. Dur- ing three days the men were to march, iu full marching order, 30 kilo- meters each day and to sleep at night in the open air. The men found the tropon food easy of digestion and it kept them in good condition. Aleuron contains but about eighty per cent, of albumen, estimated on the dry basis, but is somewhat cheaper than tropon. Caseon and eucasein are made from the casein of evaporated and skimmed nulk, dried and re- duced to a powder. AU of these articles can be used in soups, stews or even coffee. They can also be introduced into bread or crackers without altering their flavor — as much as twenty-five per cent, of tropon being thus readily tucorporated into biscuits. These substances are aU of undoubted food value and might with advantage be used to increase the protein of the emergency ration. Their taste, when apparent, is not at all disagreeable, and their continued employment for several days, in coimection with other articles, is said not to induce distaste for their use. Among the prepared foods the concentrated or desiccated stews and soups are very successful; being fairly compact, palatable and possessed of considerable food value. There are numerous very palatable mixtures of cooked beef and vegetables put up in hermetically sealed tins, but these unfortunately possess the fault, as regards an emergency ration, of contain- ing a high proportion of moisture, probably sixty to sixty-five per cent., and thus being unduly heavy for their nutritive value. They can be made somewhat drier, but only at the expense of palatability. As ordi- narily put up, the can contaias about one and three-fourths pounds of meat and three-fourths pound of vegetables. Foods of this character have been supplied by American firms to foreign armies for a number of years. Simi- lar to the above is the Maconochie patent ration, now being used to some extent in the British service. This ration was very highly thought of during the last Ashanti expedition, and was reported upon as being far superior to other canned meats. In the recent Anglo-Boer War it was 286 THEORY AND PRACTICE OF MILITARY HYGIENE. much, used and was regarded as very satisfactory. For its weight, tow- ever, its nutritive value is very low; and, while valuable for occasional issue in the field, it can scarcely be considered as sufficiently concen- trated to meet the requirements of a true emergency food. It is usually supplied in kidney-shaped tin cans weighing one and three-fourths pounds; being five and one-half inches long, three inches wide and three inches high. It is arranged with two tin straps to fasten to the waist belt, and one side is depressed so as to fit the curvature of the body. It contains one-half pound vegetables, potatoes, carrots, turnips and onions, and three-fourths pound of beef or mutton. In small recesses in the bot- tom of the container are secured rations of salt and pepper and a key for opening the can. It can be eaten without preparation, or made into hash or soups. Of somewhat similar nature, though much drier and hence more concentrated, are the Bovril cartridges. The contents of these car- tridges are varied in their composition. The tin is usually divided into two compartments, which can be opened at the ends. The blue cartridge contains a mixture of beef, potatoes and other vegetables. It is prepared by adding double the quantity of boiling water and cooking for ten min- utes. The red cartridge contains in one compartment a mixture of meat extract, pea-flour, bacon and desiccated vegetables, which is cooked by boiling ; in the other compartment the contents have a chocolate basis, and may be eaten boiled or dry. These foods are very palatable and possess many good qualities. They are compact and very concentrated, are readily prepared and their food- value is very high. Their proportionate composi- tion is also excellent, and, all things considered, the Bovril foods are prob- ably the best for emergency use now on the market. A board of officers investigating the emergency ration reported themselves as impressed with the good qualities of the "Tanty Ration," a preparation tried in the French and Russian armies. This consists of a soup stock thickened with flour and containing cabbage and other vegetables with slices of boiled beef. It may be eaten cold, preferably with bread; and when boiled with two or three times its bulk of water it makes a very palatable dish. The propor- tion of meat to vegetables is said to be about one to seven. The amount of water in this food is so great as to render its nutritive value proportion- ately low, and it is not at all suited fot emergency use. A drier form of material for the preparation of soup is seen in the cele- brated " Erbswurst " of the Germans ; this being originally a mixture of pea-meal and bacon fat put up in sausage-shaped packages. According to Parkes, the sausage as first used had the following composition : protein, sixteen per cent. ; fat, thirty-five per cent. ; carbohydrates, twenty-seven per cent. As a food the " Erbswurst " appears to have been over-rated. Parkes states that when used too constantly it was much disliked by the men, and also had a tendency to produce flatulence and diarrhoea. When mixed with water it made a palatable soup. As a result of the success which attached to this food, many modifications were subsequently made, and are now on the market. These consist, in the main, of powdered peas with bacon or beef fat and condiments, the whole being enclosed in a water-proof cover and issued as a sausage or packet. Some few also con- tain powdered beef. The sausage of Boissonet, tried in the French army, contained pea-meal, lean beef and pork mixed with lard. In general, these THE KATION. 287 different kinds of " Erbswurst" are soon found to be distasteful, causing diges- tive derangements and at tbe same time lacking the sustaining qualities of fresh meat. Similar to these pea-meal sausages are certain improved com- binations, packed in tin containers, of which the so-called " Standard Emer- gency Eation," made in this country, is a good example. The latter has within the past year been used to some extent by our troops in the Philip- pines. It is put up in oblong tins, which are opened with a key. This ration is said to contain pea-meal, cracker dust, powdered beef, bacon fat and seasoning. It makes a very palatable soup, or can be made into a porridge^ and fried when cold. In an emergency it can be eaten without cooking. It has a high food-value, as wiU be seen on reference to a sub- sequent table. Its keeping qualities, as at present supplied, are not en- tirely satisfactory, and no small proportion of the tins are said to ultimately become rancid in a hot climate. In general, all the above preparations, while they yield the alimentary elements of a complete food, present these in such proportions as properly only to serve as food for a very limited time. Further, in most of them the protein is vegetable, being derived from peas and beans. It is true that the chemical values of animal and vegetable protein are the same, yet experience shows the former to be very much more easily and completely assimilable than the latter. Improving on the soup powders carried in bulk, several firms have lately put compressed tablets on the market, which are very portable, keep well, and make a nourishiag and palatable soup when heated in water. The soup tablets made by the California Desiccated Food Company are composed of lean beef, beef extract and some vegetable material, usually pea or bean flour. , They are seasoned and very palatable. The tablets are small, weighing Iqss than three ounces. Those made for commercial purposes are reported to have the following percentage chemical composi- tion: Fats, 12.22; protein, 24.79; carbohydrates, 29.55; mineral salts, 3.21. This company also makes a soup tablet contaiaing more beef, and said to have the following composition: Protein, 47.33; fat, 11.11; carbohydrates, 20.7; salts, 11.11. The Knorr and Weidner soup tab- lets are successfully made in beans, peas and lentils, seasoned with herbs, pepper and salt; when desired, beef is also incorporated. The keep- ing qualities of these tablets are excellent. Each tablet weighs about four ounces. Knorr's pea soup is excellent, rich and palatable, tasting much like rich gravy. It ordinarily requires about ten minutes' boiling. The Weidner bean soup tablet is palatable, appetizing and nourishing, and evidently contains considerable beef extract. It requires too long — twenty-five minutes — for cooking. The Kopf pea soup requires boiling for twenty minutes. It appears to be inferior to similar articles now on the market. Edward's desiccated soups and Lazenby's soups, though excellent for officers' use, are not suitable for general mihtary purposes, being either difficult to prepare or lacking in nutriment. When pow- dered beef is mixed with beef extract and powdered cooked peas, beans or potatoes, the resulting soup is almost identical with that obtained from the soup tablets now on the market. A beef combination consisting of powdered beef 150 parts, extract of beef 50, and peptone 50, is said to give excellent results. The most palatable soups are those in which the proportion of preserved vegetables is considerable. 288 THBOEY AJS"D PEACTICE OF MILITARY HYGIENE. Soup tablets are used in several foreign armies and appear to give full satisfaction. In the French army each tablet represents the daily allow- ance for a soldier, and it is said that a single wagon can readily carry one hundred and eighty thousand of these tablets. Peecentage Composition of some Concenteated and Peeseeved- Poods and Eations. Articles. Water, per cent. Protein, per cent. Fats, per cent. Carbo- hydrates, per cent. Fuel value of lOOgm. ' Calories. Brbswurst (German) Erbswurst (Knorr's) Erbswurst (Moir's) Pea sausage (Moir's) Pea cake (Neumann's) Bean cake (Schorke's) Meat cake (Hoffman's) Meat biscuit (KSnig's) Meat biscuit (Schill's) Meat biscuit (Dunmore'S) Meat biscuit (Armebis') Emergency ration ("Woolwich) Army ration (Grouvel's) Soldier's ration (Moir's) Field ration (Morel's) Pemmican (Australian) Pemmican (Arctic Food Co.) Army ration (Maoonochie) Sqrvice ration (Maconochie) Courousa Pinole Pain de Guerre Pea soup (Lazenby's) , . . . Meat peptone (Koch) Meat peptone (Kemmerich) Compressed beef Nao complete meat food (Military Equip- ment Stores, London) Tropon (Tropon Works) Emergency ration (Tanty's) Beef stew (Franco- American Food Co.).. Standard Emergency Ration (American Compressed Food Co.) Standard Emergency Ration (American Compressed Food Co.). (A) Tablet (B) Chocolate cake Ration cartridge, pea, beef, etc. (Bovril Company) Blue ration (Bovril Company). (A) Meat albuminoids (B) Chocolate basis , Red ration (Bovril Company). (A) Meat albuminoids (B) Chocolate basis , Ration cartridges, potatoes, beef, etc (Bovril Company) , Emergency ration (Bovril Company). • (A) Meat extractive basis , (B) Chocolate basis Emergency ration, British Army. (A) Pemmican (B) Cocoa paste 7.03 10.86 8.51 11.40 9.51 7.98 6.45 5.10 14.50 11.89 8.51 6.94 14.71 53.91 37.45 2.89 7.35 63.56 76.59 31.03 7.83 10.68 14.16 40.60 38.29 61.38 53.93 9.17 66.01 66.18 6.65 6.31 1.00 14.18 45.00 1.30 27.71 1.60 41.66 12.20 1.66 3.71 4.49 21.00 17.50 15.75 21.00 30.53 16.72 24.34 8.30 34.70 10.81 15.75 8.00 30.57 33.44 32.94 51.70 17.75 15.30 9.73 24.10 7.50 10.75 23.75 49.69 50.26 31.05 13.02 88.50 13.66 15.48 31.00 18.75 6.63 21.94 22.19 7.25 31.50 6.44 23.00 46.75 7.35 59.38 6.50 23.30 33.96 33.38 32.30 3.66 17.20 24.76 6.10 2.50 8.06 15.80 18.11 18.77 14.72 23.60 42.08 39.55 12.76 5.48 21.23 4.50 .50 1.60 2.87 "5.83 20.63 .29 10.23 11.88 21.65 30.39 31.36 17.44 5.35 39.60 15.13 39.85 4.47 24.63 28.97 36.93 13.08 45.76 35.74 47.91 37.40 53.10 43.10 39.73 76.70 56.70 67.94 58.04 65.58 31.45 6.12 10.54 38.33 7.35 5.88 37.35 73.67 76.80 53.58 3.54 10.58 1.32 8.83 5.45 38.35 50.74 69.44 40.66 33.40 60.06 30.99 60.53 27.00 9.89 60.19 5.64 74.68 480.0 441.1 478.4 498.8 335.9 391.1 492.4 405.2 357.0 397.8 449.4 470.0 438.8 358.0 397.7 603.3 574.5 303.9 114.9 408.2 370.5 379.0 337.8 230.4 216.4 181.5 303.9 510.8 200.6 215.7 535.9 519.4 517.8 444.4 355.7 559.0 406.4 550.5 273.8 514.3 550.5 641.3 462.7 THE EATION. 289 Desiccated vegetables were at one time a part of the army ration. They are still used in the navy, and are said to be fairly satisfactory in that service as substitutes for fresh vegetables. The military force sent against the Mormons in Utah is said to have owed its preservation from scurvy chiefly to these desiccated vegetables, when little else of an an- tiscorbutic nature could be obtained. During the Civil War they were not greatly liked by our troops, probably because of improper preparation. They are at present used in various foreign armies ; in the British army they are said not to be generally popular. In the Ashanti expedition of 1895 the desiccated potatoes and onions were reported as being excellent, however, and the men did not seem to tire of them. In this country desiccated vegetables are made by a large number of firms. Dried potatoes are sold in two forms — sliced and granulated. In either case the potato is easily cooked and is very palatable. It should be soaked in cold water first for some time, then slowly boiled, or, what is much better, steamed. When used in soups, too great quantities should not be employed. Dried and compressed vegetables other than potatoes are also now prepared so per- fectly that, if properly cooked, they furnish food of excellent character. Analysis shows that dried, compressed cabbage contains the solids of seven times its weight of fresh cabbage; while ordinary mixed vegetables, after desiccation, contain five and one-half times the solids of the fresh vege- tables. Beans, cooked and desiccated, are said to be excellent. As anti- scorbutics, dried vegetables are much inferior to the fresh article. Morache states that this is due to the fact that compression removes nearly all the salts and leaves little but cellulose. Still, where fresh vegetables cannot be had, the preserved articles are very much better than nothing. Dried vegetables, however, contain little nutriment for their bulk, and hence should not be included in an emergency ration, however valuable they may be for continued use in the field — and the same also applies to desiccated fruits. For emergency use, coffee has been prepared in a variety of ways. Duriag the Civil War it was made into extracts, mixed with sugar and sometimes milk. A little of this could be added to either hot or cold water, and did not require boiling or settling. These extracts are said not to have much of the flavor of coffee, were often adulterated with licorice or other substances and were not popular among the men, so their use was abandoned. Efforts have been made to preserve coffee, previously roasted and ground, in small hermetically sealed tins. This, however, is by no means a perfect means of prfeservation, since after a few months at the longest the coffee sours. The sterilization of the contents and the total exclusion of air from the can being impossible without ruining the coffee, the sealing of the package only temporarily delays deterioration. Coffee is also roasted, ground and compressed into tablet form. These tablets do not keep well and the volatile oils are soon lost; hence they must be used within two or three weeks at the latest. In the French and German armies, coffee mixed with sugar is issued in hermetically sealed tablets. Each tablet weighs an ounce and will make about a pint of coffee. In this preparation much of the aroma is said to be retained — ^but Laveran remarks that these tablets "are quite inferior to the freshly roasted article, though very convenient for transportation." Experiments have 19 290 THEORY AND PRACTICE OF MILITARY HYGIENE. been instituted with reference to sugar-coating the coffee tablets, but no good results appear to have been obtained. In our own service no better plan has been found for the emergency ration than by supplying the fresh- ly roasted and ground berry in small packets, trusting to opportunity to use or replace the coffee before great deterioration has occurred. Tea is preferred by some for field use, especially in cold climates. In bulk it is somewhat difficult to transport, but this objection is removed by com- pression, the bulk being reduced to about one-third in the process. Com- pressed tea is said to be more economical than the ordinary article through the breaking up of the vegetable cells through pressure. Woodruff' states that in using compressed tea the whole strength is given up to boiling water in five minutes, while a similar result cannot be accomplished with ordinary tea iu less than five hours. A tablet weighing one-third of an ounce suffices to make three or four pints of a strong infusion. This article is excellent for emergency rations. Saccharin is used largely iu tea and coffee tablets to give the desired sweetness of taste. For this pur- pose alone it is satisfactory ; but it furnishes no energy whatever and, as aheady stated, is much inferior to sugar as a component of the emergency ration. Cocoa is used in the English emergency or reserve ration. It is put up for field use with honey or sugar and milk, made up in the form of a paste, and its keeping qualities are excellent. It may be eaten as food or prepared for use as a beverage. It is palatable and nutritious and its use in our service is much to be recommended. Kola nut, in various forms, has been proposed as part of the emergency ration through its supposed properties of relieving fatigue and masking the sense of hunger. It has been much exploited in this country, but reliable investigation has shown that the slight stimulant properties possessed by the fresh nut are analogous to those of caffeine, and that this article has no practical value for the military service. Wine, rum and brandy are served out to the soldiers of nearly all foreign armies under the conditions in which the emergency ration is consumed. Their use in this manner would probably never be tolerated in the army of the United States, even under circum- stances when it might be of advantage. The Travel Ration. — ^When troops travel otherwise than by march- ing, or when for short periods they are separated from cooking facilities £md do not carry cooked rations, the foUowing articles are issued in lieu of all components of the ordinary ration. Articles. " Per 100 rations. Soft bread pounds, liaj Or hard bread " 100 Beef, canned " 75 Baked beans, one-pound cans number, 33 Or baked beans, three-pound cans " 15 Coffee, roasted pounds, 8 Sugar " 15 After troops have been subsisted upon the travel ration for four consec- utive days, they may be allowed canned tomatoes in addition to the above ration at the rate of one pound of tomatoes per man per day. Uncon- sumed articles of the travel ration are not sold as savings, but are turned over to the commissary. When supplied with cooked or travel rations. THE EATION. 291 soldiers may be allowed twenty-one cents daily per man for the purchase of ^liquid coffee, in lieu of the coffee and sugar portion of the ration. The chemical composition and fuel value of this ration, per man, as ordinarily drawn, are as follows : .Articles. Protein, grams. Fat, grams. Carbohydrates, grams. Fuel value per ration, Calories. Soft bread 48.45 89.47 10.43 6.13 04.61 3.77 369.38 39.60 54.70 1,355 960 Beef, canned, corned Beans, baked (one-third pound) . . Sugar . 300 230 Total 148.34 74.50 353.58 2 735 The above diet is obviously Uly balanced and contaias an undue amount of nitrogenous material -for the carbohydrates present. The fuel value of the ration, however, is probably not far from the actual requirements of the soldier under the conditions in. which the ration is intended for issue. The ration itself is not particularly palatable at best, and after a journey of three or four days it may actually become distasteful. This is a defect especially due to the lack of a suitable accessary food to eat with the bread. It would, therefore, be much to the advantage of the soldier if the addition of a small amount of fruit jelly or canned fruit was authorized. This need not be greater than a daily allowance of four ounces of jelly or half a pound of canned fruit per man. Such an improvement would add little to the cost, since the articles named are cheap and the allowance of canned tomatoes, presumably added as an antiscorbutic for long journeys, would thus be no longer required. An addition of jelly or canned fruit would also largely correct the deficiency of the ration, above noted, as regards carbohydrates. While ordinarily the travel ration is consumed for such short periods and under such conditions with respect to the expenditure oi energy as to render its exact conformation to dietary standards a matter of no great importance, yet its use may be unavoidably prolonged by unforeseen cir- cumstances — as was the case during the war with Spain — and its evi- dent deficiencies therefore become a serious matter well worthy of recti- fication. CHAPTER VI. MILITAEY CLOTHING AND EQUIPMENT. CLOTHING. AccoEDiNG to Poore, the main objects to be sought in clothing the body are to maintain the bodily temperature, and, by preventing the loss of animal heat, to diminish to some extent the demand for food ; to allow the chief heat-regulating mechanism — i.e., the evaporation from the skin — ^to proceed with as little hindrance as possible ; to allow aH muscular acts the greatest possible freedom, and to avoid interference with physiological fimction, or any compression of the body, in so far as may be possible; to protect the body from heat, cold, wiad, rain and traumatism. Uniformity. — Since the soldier is permitted to have no choice in the selection of the clothing which must be worn by him, it becomes the duty of the Government to anticipate and properly provide for his probable needs in so far as they can be foreseen. Military clothing should also be practically adapted to the purpose for which it is intended, a common-sense requirement far too frequently ignored. Considerable diversity and multi- plication of uniforms is highly undesirable. In time of war the soldier should preferably wear no different clothing from that worn in peace ; and thus the military uniform should be suitable for campaign as well as fit for gar- rison duty, parade or other ceremonial. After suitability has been obtained, the uniform may be allowed a certain amount of ornamentation and smart- ness, since these qualities play a considerable part in attracting recruits and the satisfaction of a not undesirable element of vanity in the soldier. In the British army the privilege of wearing a showy uniform is recognized as being one of the most powerful factors in inducing enlistments. The cavalry regiments in that service are never short of recruits even when the reverse is the case among the foot troops ; and this is generally believed to be due to the more elaborate uniform worn by the moimted soldiers, since service in the cavalry, by itself, is much more arduous than in the infantry. Any ornamentation authorized, however, should be readily detachable, so that for purposes of campaign the uniform proper may be rendered incon- spicuous and severely simple ; and in the field no ornamentation should be permitted save such very slight modifications as may be necessary for the designation of rank. Uniforms should never vary from the standard pat- tern, so as to allow of a more ready and certain supply from clothing de- pots. The system of regimental uniforms was responsible for much hard- ship and suffering among the British troops in the Crimean War — in spite of which the modification of clothing for the designation of various regi- ments and groups of regiments is stOl customary in certain European armies, while in nearly all foreign cavalry services the use of the regimen- tal uniform is even yet more the rule than the exception. State militia MILITARY CLOTHING AND EQUIPMENT. 293 should possess the regular army uniform, devoid of special cut or regimen- tal facings, so that if called into the general service any deficiencies may be readily remedied from a common stock. While for convenience of ad- ministration clothing should be imiform for each arm of the service, this need not necessarily be so for the entire army. Cut. — Military clothing should be simple in cut and readily adjusted or removed. Whatever be the kind of garment, it must assure liberty of movement to the soldier in all his members ; since if freedom of action is impeded by tight clothing an unnecessary expenditure of energy is re- quired and the ef&ciency of the soldier by so much impaired. The uni- form should be of comfortable looseness, particularly about the hips, arms, neck and chest — compression of the latter being especially dangerous to the younger class of recruits in whom development is incomplete and the chest is enlarging under the influence of training and exercise. A tight collar presses on the neck and induces cerebral engorgement with resulting head- ache, vertigo, frequent interference with vision and greatly increased lia- bility to sunstroke. In this connection it is of interest to note that until the last generation the regulations of the larger European armies as well as our own required the wearing by officers and men of a stiff leather or paste- board stock, two or three inches in height and scooped out at the chin, for the purpose of imparting an artificial erectness and rigidity. For the con- venience of the soldier, and the better carriage of small articles on the march, the uniform should be amply supplied with stout pockets. Grade. — For the maintenance of health as well as comfort, military clothing should vary in warmth with the climate or season in which it is to be used. Insufficent clothing for a cold climate presents obvious disad- vantages, and special protection must be provided for troops serving in cold northern posts. On the other hand, too heavy clothing in warm weather is a powerful factor in the promotion of sunstroke and exhaustion, the lat- ter also markedly favoring the occurrence of infectious disease. Hiller found that during marches of about an hour's duration, during May, the rectal temperature in the fully equipped German infantryman rose to 39.4° C. where Hghtly clad soldiers had no rise beyond 38.4° C. Soldiers should also be required to modify their clothing, from time to time, as much as may be practicable according to temperature, more especially as regards falling temperature. Inattention in this respect to climatic or seasonal variation is prolific of sickness, and the matter can often be advantageously regulated by orders. In the colder stations, where furs are issued, the command should be prohibited from wearing such clothing after the actual necessity for its use has passed. When in the field, also, as much of the outside clothing, as can be comfortably dispensed with should be removed at night. The leggings and shoes should always be taken off, or at least the lacing unloosened, and no constriction of any part of the body during sleep should be permitted. Material. — In the selection of the material for the uniform of the soldier, the chief points to be considered are its permeability to air, dur- ability and the property it has of conducting or absorbing heat. In gen- eral, it should protect not only against cold but also the rays of the sun, readily absorb perspiration and check its too rapid evaporation, and be as impervious as possible to wind and rain. For underclothing, loose tissues are preferable to compact textures, since they are more hygroscopic ; while 294 THEORY AND PEACTICE OE MILITARY HYGIENE. closely woven fabrics are desirable for outer garments, since they are more durable and readily part with acquired dust. Wool is much the best material for the military uniform, since in a variable climate, or where there are sudden changes of temperature, its use secures for the soldier a more equable body temperature. While, taken fibre for fibre, it probably does not vary so much from linen or cotton as is generally beheved, it is usually woven in such a way as to entangle large quantities of air in its meshes ; this, through its non-conducting properties, prevents sudden cooling or heating. Wool takes up water and perspira- tion readily and gives them off comparatively slowly, thus reducing cooling by evaporation to the minimum and regulating the heat dissipation of the body. Woolens are often fraudulently sophisticated in the process of manufacture, and their durability and heat-retaining value greatly lessened thereby. " Shoddy " woolens are made from old woolen rags torn asunder and respun with the addition of fresh material. Exclusive of cost, wool has few disadvantages, its main fault being shrinkage and hardening after washing. Some persons are said not to be able to tolerate wool next the skin on account of its irritating properties, but if its use be persisted in for a fortnight this intolerance wiU. be found to disappear. Cotton fabrics are hard, durable and cheap. If smoothly woven and of a light color, cotton makes extremely cool garments for hot weather. If warm clothing is desired, the material must be loosely woven so as to leave large interspaces for the retention of air in the texture. As usually woven, cotton fabrics are comparatively non-permeable to air, possessing little more than half the porosity of flannel. Cotton is largely unsuited for military purposes, since it cannot be safely worn next the body by those subject to sudden temperature changes, or liable to undergo severe exercise, unless the clothing be changed immediately after the exercise or some additional garment is donned to prevent too rapid evaporation and chilling. Cotton worn over light wool makes an admirable combination for warm weather or climates. Cotton duck sheds water excellently, pro- tects against wind and is a fair non-conductor of heat, but in severe winter weather it has the disadvantage of becoming so cold as to render contact with it almost unbearable. Canvas lined with blanketing makes a very satisfactory protection for cold climates. Linen is very hygroscopic. As ordinarily woven it is an excellent con- ductor of heat, and since it is readily saturated with perspiration it requires for the maintenance of health such frequent changes of garments as cannot be obtained in the military service. A new weave of linen, the Deimel linen piesh, is valuable for the amount of air held in its interspaces, and its use removes many of the objections formerly attaching to this material. Leather, with or without the han upon it, is impermeable to the wind and keeps the body surrounded by a layer of warm air. It finds its chief use in the military service, outside of the far northern stations, in the manufacture of the foot covering and portions of the equipment ; for which, on account of its durability, pKability and practical imperviousness to water it is well suited. Eubber, oil-skin or similar water-proof material has a special but limited value in the military service for the protection which it affords against rain. Color. — The choice of color for the military uniform should be based on MILITAEY CLOTHING AND EQUIPMENT. 295 the practical rather than the aesthetic or sentimental, although unfortunate- ly the latter considerations are the ones on which selection is usually made. The hunter always tries to harmonize his clothing to his probable sur- roundings, and the Apache, in battle, endeavors to render his person as inconspicuous as possible. Among lower forms of hfe there are many striking examples of the powerful influence of color, as adapted to envi- ronment, upon the successful maintenance of existence. Grouse, snakes and other creatures closely harmonise in color with the local conditions in which they are found. Arctic hares, ptarmigan and foxes change color, with the season, while the chameleon varies its hue with each change of surroundings. It should never be forgotten that conditions which govern lower life in the struggle for existence apply also to man in his wars with one another. At the time when infantry opened fire at no greater distance than one hundred and fifty to two himdred yards, color was not of so much importance, although even then of advantage in concealing numbers and evolutions ; but to-day, with long-range arms using smokeless powder, it is of the utmost importance to proscribe all colors which can be distinguished at long distances and so furnish a mark for hostile sharpshooters. The readiness with which a color can be seen of course largely depends upon its background, it becoming less and less visible as the two shades approach each other. Thus a black object, indistinct on a dark background, be- comes very apparent by contrast if surrounded with snow. The results obtained by Gerard and Devismes, with reference to' the visibility of targets of different colors placed at the distance of 300 and 600 meters and observed under very diverse conditions of light and back- ground, are shown in the following tables : 300 METERS DISTANCE. Clear Weather. Cloudy Weather. AT Night. Color of Target. 4 11 f |i If ^1 a p 11 "^1 il -^1 1 R 4 3 2 1 7 6 ;s 3 4 5 1 6 7 i z 3 4 3 2 7 6 3 CQ 4 3 2 1 5 6 4 5 6 8 8 8 S 3 7 6 8 8 8 i z 4 3 3 1 5 6 g 6 8 8 8 8 8 a 3 4 4 3 6 6 4 3 4 4 2 6 7 § 4 3 3 8 8 8 i 1 Scarlet 4 3 2 4 7 7 4 5 4 1 7 7 3 4 3 3 7 6 2 4 7 1 5 3 1 6 7 4 3 3 3 7 6 f) Green 4 Dark blue White 4 8 Gray 8 Ashy -brown .... 8 Color of Target. 600 Meters Distance. Open country. Eocky country. On the seashore. Over water. Against earth- works. Against stone- work. Scarlet Green Dark blue . . White Gray Ashy-brown [The number 1 designates the color seen the most readily and the number 7 that seen least readily. The number 8 signifies that the target of that color could not be seen at all. ] 296 THEORY AND PEACTICE OF MILITARY HYGIENE. According to the above figures, the arrangement of colors in the order of their conspicuousness, averaged under the various conditions in which the experiments were carried out, is as follows : White (most conspicuous) 2.83 Dark blue 3.75 Scarlet 3.91 Green 4.08 Gray 6.87 Ashy -brown (least conspicuous) 6.91 From this it is seen that under all conditions the United States army blue draws fire about twice as readily as the recently adopted light brown khaki uniform, the latter possessing the most desirable of all colors. The fact has also long been noted, in our practice manoeuvers, that when one com- mand was clothed iu the brown fatigup dress, such troops disappeared from view long before those wearing the regulation blue uniform. Clearly, the blue uniform should not be worn in campaign, even if its retention be thought necessary for garrison use. Besides being least conspicuous, the effects of ordinary wear are also less apparent on fabrics of a light brown or neutral color. Common experience, as well as the investigations just noted, shows that neither white, blue nor scarlet is a suitable color for military clothing. The Austrian army abandoned the white tunic after its disastrous war with Italy ; and the English reserve their scarlet tunics for parade and cere- monies, adopting the brown khaki for actual service. The Russian army unifbrm is dark green, most excellent for summer service in a wooded country, but this color is properly modified for wintry weather and a gray landscape by the use of a gray sheepskin cap and long overcoat of a slaty- gray color. The French infantry wear dark blue coats, red trousers, for- age caps and blue overcoats — ^the most deadly combination used by any army except that found in our own garrison uniform. The Belgian uni- form is similar to our own but slightly less objectionable, the tunic being a lighter blue and the trousers gray. The color of the Spanish uniform on the home stations is similar to the French, but the coloring is also some- what subdued. The advantage of the light green coat of the Italian ser- vice is more than neutralized by the white shakos, trousers and leggings which are also worn. The G-erman xmiform of slate-colored tunic and trousers of lighter shade is deadened in winter by a neutral tinted great- coat — ^the color of the Japanese uniform for cool weather being practically identical with that of the German service. 'No part of the clothing or equipment should be of burnished metal, since through the glint of reflected light a hostile fire may be drawn from long distances. Buttons should therefore be of horn or bronze metal. The Russians have discarded metal scabbards in favor of those made of wood .and covered with hard rubber. No colored facings, except perhaps a narrow shoulder strap to designate, the arm of the service, should be allowed on the uniform, nor should any conspicuous mark of rank be per- mitted — as tending to draw fire. Cross straps of contrasting color should never be employed, nor should our blue cartridge belt be used with khaki uniforms. White helmets make a conspicuous mark, and their use was soon abandoned by the French in Tonquin, in favor of a neutral gray, for this reason. Permeability. — Its perviousness to air plays an important part in the MILITAEY CLOTHING AND EQUIPMENT. 297 hygiene of clothing. If there be not ready atmospheric circulation and resultiDg evaporation of sweat from the surface of the skin, a disturbance in the mechanism regulating the dissipation of heat is certain to result ; this varying in its results from slight discomfort on the part of the wearer to the production of exhaustion, heatstroke and even death. Pettenkofer found that the permeability of various textures to air, flannel being con- sidered as 100, was as follows: Flannel 100 Linen 58 Buckskin 51 Silk Glazed leather , 40 1 Hitler compared the perviousness of wet and dry cloth, usiug a press- ure of 28 cm. of water, and demonstrated the truth of the common idea that moisture renders fabrics much less permeable to air. His results on the uniform clothing of the German army, measuring the amount of air which would pass through a given surface iu a given time, were as follows : Dry clothing. (Liters of air.) Wet clothing. (Liters of air.) Diminution in Permeability. Military cloak (cavalry) Officers' doeskin Military tunic (soldiers'). . . . Military trousers (soldiers'). 54.77 48.41 58.63 52.18 14.9 3.9 5.3 9.3 39.87 45.51 53.33 42.98 After soaking in water for twenty-four hours the cloth of the German tunic would not permit the passage of air under a pressure of less than 3 mm. of mercury. Kolb estimated from his experiments that, if the per- meability to air of the uniform of the French officer and soldier when dry was regarded as 100, the exposure of such uniform to an atmosphere satur- ated with watery vapor reduced its permeabiLLty to 75 in the case of the officer, and 50 in the case of the soldier. Thus on close, humid days, or after a shower, the damp or wet clothing of marching soldiers does much to favor the occurrence of overheating and sunstroke among them. Absorption and Conduction of Heat. — The absorption of heat from the solar rays depends only to a slight degree upon material or texture and is chiefly influenced by color, absorption of heat being least in the light shades and increasing according to the following scale — white, light yel- low, dark yellow, light green, dark red, dark green, light blue and black. Laveran found that a thermometer wrapped with white wadding and ex- posed to a summer sun gave a temperature of 32° C. where another thermometer wrapped in black wadding registered at the same time 42° C. ; and Coulier foimd that a thin white cotton tissue superimposed on dark woolen reduced the, temperature of the latter by as much as 12.6° F. Since white has the least absorbent power as regards heat, it is the usual color for clothing in tropical regions. It is, however, not suited for mili- tary purposes except in garrison, siace it is readily soiled and affords a most conspicuous mark for the enemy. For military use in summer or tropical campaign the color of the uniform should be of light gray, light yeUow or dusty-brown ; the latter, as exemplified in our khaki clothiug, probably best answering both sanitary and military requirements under aU circumstances. From its greater absorption of the solar rays it is very de- sirable that the blue flannel shirt, in preventing overheating of the soldier. 298 THEOEY AND PEACTICB OF MILITARY HYGIENE. be discarded for tropical service — where a blouse is rarely worn in the field — and be replaced by a shirt of similar material of light brown color. When not in the direct solar rays the absorption of heat depends upon the material and texture, color entirely ceasing to be a factor. Kolb found that wet fabrics conduct heat more readily than dry fabrics; old clothing better than new clothing. On the other hand, clothing, when wet, radiates heat less readily than when dry. Color appears to make no, difference in the power of heat radiation — the power of absorbing heat, other than that of the direct solar rays, being in general equal to the radiat- ing power. Hammond noted that a cylindrical vessel containing water at "150° F. cooled 10" F. in fourteen minutes if covered with woolen United States army uniform cloth, and in seven and one-half minutes if covered with linen shirting, the other conditions being the same. The absorption of odors partly depends upon color. According to Parkes, black absorbs the most ; the absorptive power varying in a decreas- ing scale through blue, red, green, yellow and white. As far as texture or material is concerned, the absorption of odors is directly proportionate to the hygroscopic properties possessed by the fabric. Wool absorbs odors more readily than cotton or linen — and hence the suitability for its purpose of the cavalry stable frock, made of white cotton duck. Absorption of Moisture.^ — Goulier distinguishes between water of interposition^ — retained in the meshes of the fabric by capillarity — and hygroscopic moisture due to the absorption of water by the fibers of the material itself. According to Klas-Linroth, the amount of hygroscopic moisture taken up by a given fabric is determined by the amount of atmospheric humidity, temperature having little influence. The rapidity of absorption is very great during the first few minutes, and sixty per cent, of the water neces- sary to saturation is then taken up — the maximum being reached in twenty-four hours. HOler showed that flannel was more than twice as hygroscopic as cotton. Pettenkofer found that 1,000 parts of dry flannel would take up 913 parts of water, while the same weight of linen would take up but 740. On slowly evaporating this water for seventy-five min- utes the linen lost 511 parts of water, the flannel 456. Dming the thirty minutes following, the linen was deprived of 130 and the flannel of 148 parts; dming the next thirty minutes the linen 44 and the flannel 115. It has been shown that fabrics applied to the naked skin take up moisture from it less rapidly than does the external air. Flannel placed under these conditions took up, according to Klas-Linroth, only 44 parts of water per 1,000 of the fabric, where 174 parts were taken up by the free air. With regard to the rapidity with which water is absorbed by clothing, as well as its amount, on exposing a French infantry overcoat to an artifi- cial rain of moderate intensity the following results were obtained by Kolb : Kilograms. Weight on removal from the storehouse 2.225 Weight after twenty-four hours' exposure in an atmosphere saturated with moisture 2.355 Weight after an exposure of one minute to the rain 2.605 Weight after an exposure of three minutes to the rail) 3.140 Weight after an exposure of six minutes to the rain 4.385 Weight after an exposure of fifteen minutes to the rain 5.175 Weight after drying for twenty-four hours in the open air 2.970 MILITAEY CLOTHING AND EQUIPMENT. 299 He also found that although old cloth took up moisture at the outset much more readily than new, this relation was soon reversed ; the worn fabric ultimately being able to retain less moisture than the new. Lorenz has experimented with regard to the increase in weight of the uniform of the German foot-soldier from water of interposition, obtaining the foUow- ihg results : Kilograms. Total Weight of clothing before wetting 7.074 Total weight of clothing alter immersing in water 18.273 Total weight after drying for twolve hours, in a dami^ and cold atmosphere. 11.353 Experiments made by the writer show that the blue uniform or over- coat of our service will take up five or six pounds of moisture even in a rainfall of no very great intensity. Although this weight is small and is a matter of no special importance when the distance to be marched is short, the matter becomes quite different during a long day's journey. Five pounds carried through an infantry march of sixteen miles is equal, in the expenditure of energy required, to carrying eighty pounds one mile — or, if the weight of the equipment be assumed to be about forty pounds, the weight of the moisture absorbed practically diminishes the day's march which the soldier can perform by two miles. Obviously the difference of two miles, in the attempt to seize a strategic point or re-enforce a fighting column, may mean the difference between victory and defeat ; and the fail- ure of Napoleon's re -enforcements to arrive at Waterloo was said to be due much to such conditions as are gi'.en above. These facts show the greatly increased expenditure of energy required for the carriage of the clothing during rainy weather, in addition to the unfavorable condition of terrain as regards marching so produced, and illus- trates the importance of proper water-proofing of the outer garments of the soldier as a matter of military and strategic importance as well as a sani- tary precaution. Water-Proofing. — ^Wet clothing is heavy and uncomfortable, and hence is both fatiguing and depressing to the morale of an army on the march. Fabrics conduct heat much more rapidly when moist and their permeabUity to air is greatly impaired, thus both favoring chniing of the body during cold and interfering with the evaporation of perspiration in hot weather. Water-proof clothing of proper character would, therefore, be of the greatest advantage to the soldier — but tissues which are impermeable to both air and water are totally unfit for general mihtary purposes. Eub- ber garments, or those of oil skin, cannot be safely worn any length of time by marching soldiers, since, while impervious to water, they prevent the passage of air and keep the wearer constantly bathed in moisture through the non-evaporation of perspiration ; the same objection applies also to the use of cloth water-proofed by the use of gutta-percha, shellac, .lacquer, paraffine and similar agents. Under severe exercise the use of water-proof garments of this character soon becomes very distressing. Scoff'ern advised treating cotton or linen material with a bath of am- moniacal cuprous oxide; this substance possessing the power of bringing cellulose into a solution from which it may be precipitated by the action of an acid. A better plan for the water-proofing of such clothing, how- 300 THEORY AND PRACTICE OF MILITARY HYGIENE. ever, is based upon the deposition in the fibers of an insoluble compound obtained by passing the tissue through a bath of a metallic salt, usually iron or alum, and then treating it with a solution of soap. This method was improved upon by Dujardin, who employed a solution of acetate of aluminum, which decomposed on drying and caused a deposition of the metal inttlie texture. Hiller and Lorenz found that acetate of aluminum used in this manner, rendered garments satisfactorily water-proof, while at the same time it permitted the access of air in sufficient quantity to cause the ready evaporation of the perspiration. In the experiments of the former an unimpregnated fabric permitted the passage in a given time of 54 liters of air, where similar material, after being water-proofed, allowed the passage of 52.98 liters — ^but if the untreated cloth was thoroughly wet only 14.9 liters of air passed through, while the water-proofed fabric permitted the passage of 39.8 liters under the same conditions. Hiller also found that under a pressure of 6 cm. of water an unimpregnated cavalry cloak was saturated in less than half an hour, while the passage of water did not occur in twenty-four hours with the same garment after water-proofing with acetate of aluminum. The cloak after being rendered impervious by the use of this substance, when immersed in water, absorbed 1,320 gm. (three pounds) of water less than a similar cloak not rendered water-proof. Lorenz found that the acids contained in sweat dissolved the aluminum, as did also alcohol, benzine and vinegar, and that vigorous or repeated washings also impaired the impermeability. By the use of aluminum ace- tate the color of tissues is altered but little if any, while the amount of the metal deposited in the fabric is so small as to make practically no increase in weight. By this procedure the tissues are not injured ; coarse and rough textm:es giving better results than finer ones. The method is very inex- pensive, and the entire outer clothing of the soldier can be water-proofed at a cost of about one dollar for each hundred men. It is stated that this method is now employed in the British army for the water-proofing of khaki clothing, for which purpose it is very satisfactory. Early in 1899, the attention of the writer was casually attracted to the well-known property of repelling moisture possessed by blankets woven by the Kavajo Indians from yarn spun by themselves from native wool — ■ and further investigation showed that this water-proof quality was depend- ent upon the presence of wool-fat, a substance which among civilised peoples is carefully removed from fleece before it is dyed and spun. Experiments were then begun and carried on for a number of months, when it was learned that this method of water-proofing had also been discovered by Berthier and Kolb in France at about the same period. The writer, after some experimentation, decided upon the use of a solution made up of 20 to 30 gm. of lanolin, previously dehydrated, dissolved in 1 liter of benzine. Kolb employed neutral wool-fat or suint, dissolved in petroleum ether in the propertion of 10 gm. of suint to 1 liter of solvent. Eecently a process has been adopted commercially by which the cloth is impregnated with wool-fat by the use of heated steam rollers. The first plan appears to give fully as satisfactory results and has the advantage of being cheaper. Woolen fabrics, as might be expected, give much more satisfactory results than those of vegetable origin — ^though the water-repellent qualities of the latter are much improved by this process. MILITAEY CLOTHING AND EQUIPMENT. 301 The process of water-proofing is very simple and can be readily carried out by any one, even in the field. The clothing to be water-proofed is merely immersed ia the solution, the garment wrung out and the excess of solvent allowed to evaporate rapidly in the open air ; about 3 liters of the solution being required for the entire effects of each soldier. Clothing im- pregnated with wool-fat or lanolin may be worn both in rain or sun without iU efi'ects, permits the ready evaporation of perspiration and affords better protection against rain than do fabrics water-proofed with acetate of alum- inum or other chemical bodies. The garments impregnated with wool-fat are even more permeable to watery vapor than clothing not so treated ; this being explained by the fact that moisture cannot penetrate the fibers of the cloth and cause their swelling, with consequent diminution of gaseous permeability. Little water is absorbed by material treated in this manner, Berthier finding that a piece of untreated cloth, weighing 25 gm. when dry, had its weight increased to 69.5 gm. by being exposed to a heavy rain; while a similar piece of cloth, after impregnation with lanolin, weighed only 30.5 gm. after the same exposure. In the writer's experi- ments it was found that a woolen blanket, treated with a three per cent, solution of lanoHn, did not permit the passage of water under a pressure of less than one inch, or about two-thirds of an ounce pressure to the square inch. It is noticeable that by the use of this method of water- proofing the comparative conductibility as to heat is slightly greater than in dry, imtreated fabrics, but is considerably diminished when compared .with similar wet fabrics. The gaseous permeability of cloth treated in this manner is only slightly impaired by wetting. The water-proofing by wool-fat appears to be permanent as regards or- dinary conditions, moderate washing having no effect upon the imperme- ability produced by lanolin, although prolonged washing or the use of strongly alkaline soap causes a slight diminution. The expense of water- proofing the soldier's uniform by means of this agent is inconsiderable, amounting to only about twenty cents per man. In usiag this process, which is founded on nature's provision for the protection of the animal, care should be taken to ensure equality of impregnation. The best plan would undoubtedly consist in passing the cloth, in bolts, through rollers, after being soaked in a strong solution. If large garments are soaked and then hung up, gravity wiU cause the solvent to run down and thus bring about an excess of the wool-fat in the lower portion of the fabric. In such a case the excess of solution should be wrung out, and the position of the garment be continually changed until most of the solvent has evapo- rated. In warm climates as strong a solution as five per cent, can be used on clothing, but in cold climates garments treated with this strength be- come sUghtly stiffened and " f elty " in cold weather. Weaker solutions should therefore be used in the latter instance, no greater strength than two per cent, being employed. The proper use of wool-fat for the water-proofing of the military uni- form clearly has many practical advantages. These may be summed up as follows : Impermeability to rainfall, free passage of air and water vapor, in- creased capillarity, no increase in weight, no alteration in appearance, color or odor, increased solidity and strength. To this may be added cheapness, ready attainment of water-proofing materials and simplicity of operation. 302 THEORY AND PEACTICE OF MILITARY HYGIENE. 6.— Types of Military United States Army uniform cap, witliout insignia. SPECIAL ARTICLES OF THE UNIFORM. The Head-Covering. — The ideal military headgear should be light iQ weight and color, be well ventilated, and offer little resistance to the wind. It should protect the head from heat and cold, and shield the eyes and the back of the neck from sun and rain. Its centre of gravity should be in the same vertical line with that of the head, siace otherwise the soldier will be required constantly to replace it in maintaining its equihbrium. It should not constrict the head nor interfere with the use of the soldier's weapons, while it should be a protection at night in the field and be suf- ficiently sightly for military ceremonial. It is thus apparent that the perfect military headgear has yet to be discovered. The form and color of the military head-covering are of great importance in preventing over-heating of the head, and sunstroke, by the solar rays. Jousset, in Senegal, observed that, in a tempera- ture of 50° C. in the sun, the temperature under a soft black hat was 45° C, and under a light gray helmet 32° C. ; while Geraud has noted a temperature of as much as 52° C. in the metallic helmets of the French cuirassiers. It is easy to under- stand how readily sunstroke may occur under such conditions. The crown of the head-coveriug must always be sufficiently high to afford a proper air. space above the head, and, if necessary, to permit the placing therein of a damp handkerchief, grass or leaves if such action be required by prolonged exposure to a hot sun. The forage cap of our service is very light and adapts itself well to the head without producing constriction. It has a height lq the crown of three and one-fourth inches ; the diameter of the top, laterally, beiag about six and one-half inches, and from front to rear seven and five-eighths inches. The cap is covered with dark-blue cloth and lined with black satin. The shape is maintained by a foundation of haircloth, and it is still further stiffened around the side by a band of split leather one-sixteenth of an inch thick and two and one-fourth inches wide. The slanting visor has a width at the centre of one and five-eighths inches and is lined with em- bossed green leather. The weight of the cap is about five and one-half ounces. Ventilation is provided through the perforated eyelets on each side. The disadvantages of the forage cap are that it is hot in summer, cold in winter and does not sufficiently protect from the rain and sun. It also deforms somewhat readily, particularly after repeated exposure to rain, and is frequently ac- cused, on rather insufficient evidence, of producing baldness. It affords no protection to the back of the head and neck, and for this purpose a loosely floating neck-cover — the " couvre-nuque " and "havelock " of the French and English services — should be added if the cap is worn in the field in a hot season or climate. When its use is restricted to garrison service in temperate climates, however, the forage cap has no serious defects. Fig. 97.— Types of Military Headgear. French kepi. MILITAEY CLOTHIKG AND EQUIPMENT. 303 riG. 98.— Types of Military Headgear. United States In- fantry full-dress helmet. The helmet, so long the distinctive head-dress of the soldier, is no longer required as a protection against possible saber strokes, and with this the only reasonable argument for its employment in the military service at once ceases to exist. The full-dress casque used in our army can be men- tioned only to be condemned, since it has many grave defects and no advantages over more hy- gienic headgear, even for parade. This hebnet is made of felt, and weighs, with ornaments, from seven and one-half to eight and one-fourth ounces. The visor is finished inside in green morocco. The helmet is furnished with a chia strap to hold it in position, and for additional security, when issued in the mounted service, it is provided with a helmet cord. No provision is made for ventilation in this helmet, which is stiff, unyield- ing and niy-balanced. It affords no protection agaiQst cold, and, being both black in color and badly ventilated, is exces- sively hot ia warm weather. The helmet of the British infantry is made of cardboard covered with water-proof cloth. It is well ventilated but is heavy and cumbersome, weighing fourteen and one-half ounces. The old German helmet, made of leather, weighed sixteen ounces and was ornamented in copper metal. More re- cently parts of the ornaments have been re- moved and others made of aluminum. This helmet is provided with orifices for ventilation at the base of the spike, and by turning the latter the ventilation can be regulated. The campaign hat used in our service is made of drab felt and weighs about three and three-fourths ounces when complete. The block is five and three-fourths inches deep to center of top ; the brim being two and three- fourths inches wide in front and rear and three inches wide at the sides. The hat is furnished with a sweat-band two and one-fourth inches wide, and is provided with small punched holes on the side for ventilation. For use in hot climates* it is issued with an air space under the sweat band, while a ven- tilating hole is made on each side, guarded by light wire gauze for better ventilation. The advantages of the campaign hat are many, while its faults are comparatively few. Except for use in winter in very cold climates, it is probably the best mili- tary headgear which has yet been devised, being extremely popular with troops and worn by them in preference to any other head covering, even in the tropics. Its defects include the large surface which it exposes to the wind and the readiaess with which the material breaks down on exposure to wet weather — the latter being easily remedied by contracting for hats of better quality and water-proofing them Fig, 99.— Types of Military Head- gear. German Helmet. .>#» Fig. 100.— Types of Military Headgear. TJnited States Army Campaign Hat. 304 THEOEY A2^D PRACTICE OF MILITARY HYGIENE. before issue by the use of wool-fat. This hat cannot be comfortably worn by the sleeping soldier, owing to its broad brim ; and when protection for the head at night is desirable, a small, soft cap may be advantageously car- ried in the equipment, as is done in the French, German and English armies. It has been recommended, to give a, more dressy effect to the campaign hat, that the brim on one side be looped up and fastened by a rosette or metal ornament. This implies a sacrifice of the practical and hygienic to the aesthetic — for it is obvious that if the protection afforded by a brim is desirable for one side of the head it is equally so for the other. Except in cold weather the crown of this hat should never be creased, but should be left intact or else drawn to a point in Mexican style to ensure a proper air space above the head of the soldier. This rule should be enforced by company officers. The nearest approach to the campaign hat used in foreign services is the headgear worn by cer- tain of the British and German colonial troops in Africa, and by colonial forces in Australia and New Zealand. The Alpine troops of Austria and Italy wear a slouch hat, adorned with cock's feathers, resembling it slightly in appearance. Straw hats, of a pattern approved by the commanding of&cer of the post, are permitted to be used at the more southern home stations during summer. Advantage of this permission, however, is rarely taken. In foreign military services the head-covering varies greatly in pat- tern. The French infantry kepi is similar to the forage cap discarded in our service several years ago, after a generation of usage. In the Belgian army a shako is used in the field, this being shaped like a truncated cone and having a black leather top, patent leather visor and chin strap. In the German Landwehr a similar shako is also issued. In the Spanish and Italian armies a modified shako is employed, while t^"^_^ in the British and German services the helmet is JIII3!i|jj||i used. The summer head-dress of the Eussian in- ^H fantry is a cap similar to that used by the sailors llBL ^^ ^'^ naval service; a visorless sheepskin cap II^Hk being used in winter. For garrison duty the Aus- P"^^ trian cap is similar to our present forage cap, of j^^^A which it is the prototype. In the field or in cold ^™»»«ti^ weather a slightly modified cap is issued in that PIG. ioi.-Types of Muitary service, provided with a hanging piece of thick Headgear, snako. material similar to the "havelock"; which, while usually buttoned up around the cap, may be turned down so as to protect the ears and neck. This Austrian service cap ap- pears to be by far the best covering used in any European army, though very warm for hot weather. The Outer Clothing. — ^The double-breasted overcoat with adjustable cape, used in both the foot and mounted services of our army, is made of sky-blue kersey and lined with dark-blue flannel. It is much too thin for use in extremely cold weather, absorbs much moisture and is difficult to dry when wet. It is slit up in the back to an extent of twenty-one inches, and since the skirts are thin they readily blow aside and afford little pro- tection in strong winds. The coUar is rolling and has a width of about three and one-fourth inches. It would be a much better protection if it MILITARY CLOTHING AND EQUIPMENT. 305 were about one and one-half inches wider. The lining of the cape varies in color according to the branch of the service. The cape itself is not sufficiently long to be of any great value as a separate garment ; its use for this piu'pose being sanctioned by custom, if not authorized in orders. The overcoat should be amply provided with pockets ; there being at present only a single inside pocket. It is of great importance that this overcoat should be rendered water-proof by the use of lanolin, so as to enable the poncho to be dropped from the equipment. The British army overcoat is somewhat heavier than our own, weighing about six pounds. The Belgian overcoat is double- breasted; the skirts, as in other European ser- vices, being capable of being fastened back, upon the march, so as to leave the legs free. The Eussian overcoat is also double-breasted and reaches about two-thirds the distance be- low the knee. The French, German and Aus- trian overcoats are similar but shorter. In the German army the collar may be held up, when required, by a little hood, which is concealed in a pocket in the collar when not in use. In cold weather or driving rain this hood can be put on underneath the helmet. This ar- rangement is excellent. In the Chiao-Japan- ese war, the troops of the latter were provided with a great-coat of brown blanketing, with a hood and special covering for the head at night. It was comfortable, serviceable and of good color for field service. It came nearly down to the ankles, and was gathered at the waist by a broad band, the latter being an excellent protection for the abdomen and serving efficiently for the retention of warmth. The uniform blouse is made of dark-blue flaimel, weighing thirteen ounces to the linear yard and capable of sustaining a strain of twenty-eight pounds per inch in the width of the warp ; a better quality of material being issued for non-commissioned officers. It is a single-breasted sack coat with falling collar, and is provided with an inside pocket on the left breast. It is now supplied in nine sizes — made according to the following dimensions : Fio. 102.— Uniform Overcoat. Length. Length of sleeve. Neck. width of collar. Breast. Inches. Inches. Inches. Inches. Inches. 38 31 15 li 34 m 81f m If 35 39 33i 16 If 36 39i 331- 16i If 37 39f 33i 17 If 38 30 33f m If 39 30* 34i 18 If 40 30f 34f 18i If 41 31i 35i m If 43 Waist. Inches. 30 31 33 38 34 35 86 37 38 The blouse, as usually fitted to the soldier, is liable to compress the 20 306 THEORY AND PRACTICE OF MILITARY HYGIENE. muscles to some extent and to impede the respiratory movements of the chest. While it should follow the lines of the figure in a general way it should be made loose at the neck, large in the shoulder, chest and arm, and smaU. at the wrist. Like the trousers, it should be sufficiently fuU to allow of the comfortable use of extra underclothing during very cold weather. The bottom should not be ex- tended more than two inches below the great trochanter, and for cavalry an even shorter blouse or shell jacket is preferable. Coats with long skirts are worn only iu the French and Italian armies, and pos- sess no advantages over shorter garments where drawers are issued. The blouse used in the Russian army is made double- breasted. This garment should be made with four pockets, since these, in the field, can be used with great advantage by the soldier. In the Belgian army the breast pockets are utUized for the carriage of cartridges. A rolling collar does not sufficiently protect the neck in cold FIG. 103.— Uniform Blouse. Weather, and in all the great European armies, except that of France, a standing collar is worn. In the latter service an additional protection has been found necessary, and the wearing of cravats of blue cloth has long been required. A loose jacket, cut like the present issue of the khaki blouse, is the ideal military coat. Soldiers, who wear no waistcoat, should always keep the blouse buttoned, as much for the protection of the otherwise poorly cov- ered abdomen as for purposes of military discipline and smartness. The buttons of the blouse should be made solid and not hollow, as is the case at present, and should not be of burnished metal. The blue uniform trousers, excellent in character, are made from sky- blue kersey, weighing sixteen ounces to the linear yard and capable of sustaining a strain of fifty pounds to the inch in the width of the warp. In cut, the trousers should not be made high in the waist and should be loose about the hips and thighs. The legs should be cut proportionately narrower, and the bottoms should not be permitted to "flare," as is the preference of recruits; since such trousers cannot be readily stowed in boots or leggings and are more liable to become muddy and heavy in wet weather. If the trouser legs are made too long they are quickly soiled, become worn at the bottoms and chafe the lower limbs. Both hip and side pockets should be provided. In the French and Belgian mounted service the long Lasalle trousers are worn, the lower thhds of the legs of which are faced with sheep-skin to form false boots. These trousers have many disadvantages, and it is understood that their abolition in the French ser- vice is now contemplated. Suspenders should be used in the military service in preference to the belt, and should be so colored as to present no great contrast to the uni- form shirt with which they are worn. The belt compresses the abdomen, interferes with diaphragmatic breathing, favors constipation and is believed MILITARY CLOTHING AND EQUIPMENT. 307 by many to exert a considerable influence ia the production of hernia. The belt and anything else the use of which disturbs a physiological func- tion should have no place iu the equipment of the soldier. The uniform dress-coat is of dark-blue cloth, faced or piped with cloth of a color corresponding to the arm of the service or staif corps. It is a single-breasted frock coat, with standing collar, cut square to hook in front. There is a small inside pocket on the left breast. The dress coat is the same for the mounted as for the foot service, except that it is about three inches shorter and the skirts are slashed to within three inches of the waist. When donned, the skirts of the infantry coat reach to about the middle of the thigh. This coat is furnished, ready made, in six si^es. The dress-coat has no virtue except that of warmth, and its use should be abandoned. Made tight to impose an artificial stiffness upon the wearer, its use renders the soldier incapable of properly performing the very mo- tions or duties for which he is specially trained and for which military forces are required. No man so dressed could either work or fight effec- tively, and it is to be hoped that the step in the right direction recently taken, in abandoning the dress-coat and uniform in the case of the hospi- tal corps, will be followed by its abolition throughout the army at large. Canvas suits are furnished in garrison for use by men engaged in fatigue. They are made of seven-ounce cotton duck, dyed in light brown. The coat is similar in cut to the uniform blouse, and is provided with breast pockets. These fatigue uniforms were largely used by the regular troops during the Spanish- American war, prior to the issue of khaki clothing, and proved far superior to the blue, uniform for tropical field service. Similar fatigue uniforms are supplied in foreign armies. Stable frocks and trousers of white duck have long been issued to mounted troops for the better protection of their clothing, and are excellently adapted to the purpose for which they are employed. In certain southern posts a summer uniform of white cotton duck is issued. The use of this uniform at all times is permitted to the hospital corps on duty at post or general hospitals. In most foreign armies, as the German, the uniform cloth- ing is never varied, winter or summer. The Underclothing. — The flannel shirt appears to be very satisfactory for military use in all climates. Even in tropical countries it is preferred by the men to the cotton or charpoy shirt, since with its use chilling of the body is largely prevented. It is at present issued in two grades, of eight and ten-ounce flaimel respectively. It is loose-fitting, with broad rolling collar and large breast pockets. In the field or on fatigue it may be worn without a coat, and barring its color it forms an ideal military gar- ment. When intended to be worn in the tropics or with the khaki uniform it should preferably be made in gray or dusty-brown. As issued, the shirt Fig. 104.— Inlantry Dress Coat. 308 THEORY AND PRACTICE OF MILITARY HYGIENE. should be long enough to reach the middle third of the thigh and should be provided with cotton neck and wrist bands to prevent undue retraction and constriction by shrinkage. This garment does not readily show dirt, and hence in the field it is frequently not washed as often as desirable. Wlien dirty and fuU of ' sweat the flannel is somewhat irritant to the skin and may then favor the occurrence of urticaria, eczema and furunculosis. Three grades of woolen undershirts are issued in our service, known as light weight, light quality and heavy quality. They each contain sixty per cent, of wool and forty per cent, of cotton. A white cotton undershirt is also issued ; this, like the woollen undershirts, being supplied in six sizes. Both quality and grades leave little to be desired. The equipment of the German soldier includes three cotton shirts ; a recent order providing also for the issue of a simple knitted woolen shirt in winter. In the British service each man is required to possess two woolen shirts, while in the French army the shirts are of merino, containing one-third cotton and two-thirds wool. Drawers are intended primarily for cleanliness and the prevention of chafing, and secondarily for the warmth of the legs and lower portion of the abdomen. In warm weather, where the blue uniform is worn, troops are inclined to avoid the use of drawers. During the march the dusty trou- sers, saturated with perspiration, soon become filthy and by their heat and coarseness irritate and chafe the unprotected legs, while in camp the dis- use of drawers is liable to be followed' by surface chilling and intestinal disorders. Hence drawers should be required to be worn under all circum- stances ; their use, if necessary, being forced by inspection by company officers. They are supplied in canton flannel and cotton jeans, being issued in five sizes. Those of the former material are cut too loose for the mounted service, and are liable to wrinkle and produce chafing and exco- riations. They should be fastened at the bottoms with tapes rather than by buttons. Light dtawers, made of balbriggan, should be issued. As a matter of fact, soldiers in garrison largely refrain from drawing undercloth- ing from the Governlnent and prefer to obtain more desirable underwear from outside sources. ■' No drawers are issued to troops in the English and Spanish services; the French soldiers being allowed two pair of cotton drawers yearly. In the late winter campaign in China the Japanese troops, in addition to the regular imderclothing, were provided with paper shirts and drawers. These were worn in very cold weather, the former between the usual under- and overshirts, and the latter over the ordinary drawers, and were said to be very warm and comfortable. The Jaeger underclothing, used largely in the German army, is so woven as to be non-u-ritating to the skin, while the arrangement of the constituent hairs facilitates the removal of moisture. As mentioned elsewhere, military clothing should be cut loose to per- mit, if occasion demands, of the wearing of more than one set of under- clothing; since, as is well known, animal warmth is better preserved by the use of several garments than by a single one of their aggregate thick- ness, owing to the air confined in their various layers. During campaign an extra pair of socks, suit of underclothing and shirt should always be carried by the soldier. Woolen abdominal protectors are issued in several foreign services. MILITAKY CLOTHING AND EQUIPMENT. * 309 They are used by the French troops serving in Algeria and at tropical sta- tions, but are not worn by soldiers on home service. In the British army the constant wearing of the abdominal protector is required by regulation ; obedience being enforced by frequent inspection and dereliction being fol- lowed by severe penalty. In the British service, however, no drawers are issued, and to take their place some adequate -abdominal covering is re- quired; but where long woolen shirts and drawers are worn, as in our army, such additional protection is neither necessary nor desirable. For the sick, or during epidemics of diarrhoea, cholera or dysentery, the abdominal band may be worn with advantage — but with healthy men, particularly in hot weather, it is a cause of discomfort and fatigue. If sufficiently tight to retain its position, the band interferes with the action of the abdominal muscles and with intestinal peristalsis, and thus largely favors constipation. The Coverings of the Extremities. — Gloves are necessary in winter to enable the soldier, without danger of frostbite, to manipulate his weapons with precision. In our service a fur glove is issued for this purpose, but this is unnecessarily warm, bulky, and cumbersome except in very cold weather, and a medium weight glove should be provided. White cot- ton gloves are issued not so much for warmth, of which they possess little, as to improve the appearance of the soldier for parade or other ceremonial. Cavalry habitually wear gauntlets when mounted. In the French service the use of mittens is authorized for the colder stations. The Japanese troops use mittens made with two divisions ; the forefinger' being inserted in one, when desired, for the more ready use of the trigger of the rifle. In the Eussian and German ser- ^"*- ^^liiiiek^*"'^ vices the soldiers in winter wear woolen gloves fastened together by a cord which passes up through the sleeves and over the shoulders. This arrangement is excellent for the prevention of loss, es- pecially liable to occur during winter campaign. The military stocking is an article which has not received the attention which its importance warrants. No stockings are issued in the Spanish, French and Italian armies, a fact to which the frequency of injuries of the feet in these services must be largely attributed. The use of stockings promotes cleanliness and prevents saturation and hardening of the shoe leather by perspiration — a potent factor in the production of excoriations. In wioter, also, the soldier, in rain or snow, with shoes often penetrated by icy water, is very liable to frostbite; this accident being in great part avoided by the use of woolen socks. In the war of 1870-71, cases of frostbite of the lower extremities were extremely common among the French troops, who had no protection for the feet other than leather shoes of notoriously poor quality; while freezing of the lower extremities rarely occurred in the German army, each soldier of which was provided with two pair of knitted woolen stockings. The annual clothing allowance of the British army includes three pair of woolen socks per man ; the Swiss soldier yearly receiving two pair. In the German army stockings are only used in winter ; pieces of cloth about fifteen or twenty inches long and four inches wide, which the soldier wraps around his feet, being issued for 310 THEORY AND PEACTICE OF MILITAEY HYGIENE. rjSst?; w^ m. MS.: I"-'': m Fig. 106.— Woolen sock. summer use. These strips, or " Fiisslappen," are made of linen, canton flannel or knitted ■woolen material, varyiug with the temperature and the moisture of the feet. They are applied by starting «ne end smoothly un- der the ball of the great toe and wiudiag like a bandage over the back of the foot from within outward, finally coveriug the heel, while the last corner is laid smoothly across the instep. In the Eussian army such strips are worn throughout the year, the company officers being responsible for their cleanliness and proper application. These pieces of cloth are merely economical makeshifts I-„,._ ..J, for better articles, but their use does not appear [i;!;ii *,j to be as detrimental to the integrity of the feet iiib m'" V ^® ^*' ^^^ sight would seem to be inevitable. It J ft*. I' u is claimed for them, as compared with stockings, that they can be more readily washed and dried, take up less room, and, by being folded in differ- ent ways, are worn out more uniformly and less quickly. To take the place of stockings the French soldier, during the war of 1870-71, often filled the vacant space in his shoes with straw. In our own service both woolen and cotton stockings are issued, the latter being provided in two grades and five sizes. The woolen sock is made of pure wool and is furnished in three sizes ; size ten and one-half being required to weigh three pounds per dozen pairs. These socks should be issued in at least six sizes, since when lU fitting they are provocative of corns and blisters. If too small, the toes are cramped and the wear- ing out of the material is hastened ; if too large, the stocking is apt to wrinkle at the heel and so induce the occurrence of blisters. To prevent the latter accident the sock should be held up, preferably by pinning to the drawers — but the use of garters is objectionable in that they bind the leg and favor the occurrence of varicose veins. The wearing in the field of stockings which have been worn through or darned should always be avoided, and before entering upon a campaign the kit of the soldier should be inspected for their elimination. Given the most perfect shoes, if a man has a hole in his sock his foot wUl be inevitably blistered, and in this connection it may be emphasized that the rough-and- ready darning usually given these articles by the men is nearly as bad as the holes themselves. Woolen stockings, the only kind issued in foreign armies, and until quite recently in our own also, induce free per- spiration of the feet, but are much more suitable for the use of troops in the field during the march, as being less liable to induce chafing. They should, however, be changed on arriving at camp, and their use necessitates even greater at- tention to the cleanliness of the feet. "With a heavy stiff shoe a thick soft stocking is practically a necessity for constant inarching — a fact throughly recognized by old soldiers. Fig. 107.— Cavalry Leg- ging. MILITAEY CLOTHING AND EQUIPMENT. 311 Leggings, made in three sizes of fifteen-ounce brown canvas duck, to be worn in the field or on campaign, are now issued to all branches of the service. They are a great protection for infantry, particularly in wet weather or when campaigning in a rough or timbered country; and since their adoption our foot-troops have been freed from the necessity of facing their trouser legs with canvas or buckskin, as was formerly customary in frontier service, to prevent their being worn out or cut by grass, brush or briars. For cavalry the legging is a marked improvement over the boot, since it answers every purpose when moimted, is light and pliable, and, if on dismounted service, does not impede the performance of any duty. Leggings are much liked by the troops, since they protect the legs, prevent muddying of the trousers, promote cleanliness and dryness and are readily cleaned at the end of a march. Their disadvantages are those of extra articles of clothing to be looked after, together with their slightly addi- tional weight. If worn too tight they bind the muscles of the legs and thus may considerably increase the fatigue of the march; for this reason shorter leggings are desirable for foot troops. While the strap passing un- der the instep promotes smoothness of the legging over the shoe, in a muddy country it is a serious disadvantage through the mud which it collects. In this respect it is a question J whether the English style of legging is not superior to \ "^i j our own. 1 l^i / The Italian infantry wear short linen leggings or ) ^j j gaiters; while in the Japanese service a legging of ^^^ 'NCj \ white canvas, similar in cut to our own and reaching \ ^j \ nearly to the knee, is worn by the foot troops. Long \ra«K,n £i 1 leggings made of leather are used in the British army w-uutX^ — t — ^though recently " putties " have been much used — and ^ " • i-i-Ai- ■ii-i.ifi.ij! 1 T. Fig. ICe.-Legglng Used m the Austrian service the halt- boots formerly worn by in Italian Army. troops have been replaced by shoes and leggings. No leggings are used in the German or Eussian armies ; but boots are used, and the trousers tucked into them before beginning the march. In India, "putties " are used instead of leggings, both by foot and mounted troops, and are said to be satisfactory. It will not be disputed that the marching powers of infantry are a most important factor in the conduction and success of a campaign, and that the army which marches best, other things being equal, is the successful army. History is full of instances where battles and campaigns have been won more by marehiag than by fighting, and rapidity of movement will be no less an element of military strategy in the wars of the future than it has been in the past. Napoleon is reported to have said that he made war not so much with the arms as with the legs of his soldiers ; while Marshal Niel considered good shoes for his irifantry as important as mounts for his cavalry. Saxe said that the whole of military tactics was in the legs of his soldiers — and Wellington enumerated the three most essential parts of the soldier's equipment as a pair of good shoes, a second pair of good shoes and a pair of half-soles. Hence it is that of all the protective cov- erings which the foot-soldier wears, his shoes are by far the most impor- tant from a strategic standpoint; since upon their ease and the comfort of their fit, their pliancy and lightness, depends his military efficiency. War 312 THEORY AND PEACTICE OF MILITARY HYGIENE. is a business, and the soldier whose badly-shod feet are unable to carry him into battle fails of the purpose for which he was trained — and instead of being an added strength he becomes an incumbrance. Lindau, in 1883, found that of ten thousand men discharged annually from the German army for physical disability, in time of peace, four hundred were for affec- tions of the feet — a proportion which would be greatly increased in time of hostilities ; while, as stated in a previous chapter, over thirty thousand German soldiers were incapacitated for duty during the first few weeks of the Franco-Prussian war on accoimt of injinries of the feet — ^these having largely resulted from the use of poor foot-wear, hardened by long storage in the supply depots. L4ques, in 1882, found that excoriations of the feet figured as one-third of all the causes of exemption from active service among young French soldiers during campaign. In character, the military shoe should afford the greatest amount of protection with the least injury to the, foot of the wearer. It should possess solidity and rigidity, yet at the same time have a certain amount of suppleness. It should protect against the cold in winter, against heat in summer and moisture at all times. Evaporation of perspiration should be readily carried on. The shoe should be so fashioned as to be readily donned and removed, and should be light in weight. The importance of light foot-wear for the soldier is so fully appreciated by the Germans that even the nails of the military shoes are made of aluminum in the effort to reduce weight. According to Viry, "each gramme more or less on the shoe is equivalent, so far as the effect on the wearer is concerned, to one kilogramme more or less to carry through the journey." The shoe should also be made of durable material presenting no interior roughness, should be reasonably cheap, and should be supplied in such a variety of sizes as to render the fitting of the foot a matter easy of accomplishment. In fashion, custom should be disregarded for utOity. The sole should conform in shape to the natural outline of the foot ; the outer margin of which is a long curve, while the inner side approaches a straight line. Ample space for the fifth metatarsal should always be en- sured. The toe should be slightly roimded, the point being toward the inner aspect rather than in the centre. The fore pait should be broad to allow for expansion ; but no great breadth is necessary at the middle of the foot, which does not spread to any extent. To protect the sides of the foot against stones, the sole should be wider than the uppers by about one-eighth of an inch ; but if it project too far it serves to accumulate mud, and thus increases fatigue in marching over muddy roads. The sole should be supple, since if it be too thick flexibility is lacking, while if thin the protection is insufficient and the shoe lacking in solidity. The insole should be smooth and slightly concave to receive the heel and ball, but there should be no contact or interference with the free play of the ankle, which is intolerant of support except at its extremities. The heel should be fixed in such a manner that it cannot be detached. It should be broad to afford a solid base, and low to prevent the sliding forward of the foot, with resulting discomfort and cramping of the toes. The length of the pace as well as the stability of the individual is directly influenced by the height of the heel — and it may fairly be questioned whether the actual omission of the latter, as is done in the Greek army, MILITAEY CLOTHING AND EQUIPMENT. 313 may not be of advantage. For the erect and artificial gait of civilized peoples the use of the heel is, no doubt, largely responsible, and with its retention the successful use of the natural or aboriginal gait, described in a previous chapter, will be accomplished only with some difficulty. To diminish the vibration of the body, particularly that of the encephalon, pro- duced by the impact of the foot upon the ground, CoUin proposed to make the heel of rubber. He claimed as a further advantage for this device that the energy stored up in the rubber compressed by the weight of the soldier would assist in his propulsion. Trial of such a shoe in the French ser- vice has appeared to result favorably, it being found that the same effects can be produced by a disc of rubber inside the shoe just above the heel. For field service the heel and such part of the sole as touches the ground in walking may advantageously be fortified with hob-naUs or strips of leather ; thus adding to their durability and giving better foothold, particu- larly on grass or rough or frozen ground. They should not be too many in number and should be firmly fastened and not liable to fall out, since when the latter occurs the sole ceases to be water-tight. In the German service these nails and those used in fastening the heel are made of alumi- num to diminish their weight. Metal plates, sometimes advised, take up much of the wear, but are heavy and soon become smooth and polished, causing much discomfort and fatigue to the wearer through the insecure foothold given. There should be no surplus leather in the upper, nor should it possess interior seams to bruise and abrade the skin. The instep should be high, for if it is not the men will frequently cut the vamp and tongue, thus destroying the support to the ankle and injuring the appearance. The leather around the ankle joint should be light, to provide for the rocking motion of the foot, yet should fit snugly. The tongue should be of the bellows style, and the top of the shoe should be cut high. The shoe should be hollowed out behind to prevent friction of the heel. The meth- od of fastening should be easy and simple — the use of lacing best fiUing this indication, as well as allowing ready adjustment to the swelling of the foot on the march. The shape of the foot at rest differs from that of the foot in action. In the normal adult foot the weight is supported on the outer border of the sole, the heel and the anterior extremities of the metatarsals. The toes bear little weight when standing, more when walking and most of all when running. The great toe is a direct prolongation of the first metatar- sal, and its single joint is acted upon by the strong flexor muscle, which, in propulsion, tends to shorten the foot and preserve the plantar arch as well as to approximate the inner side of the foot to a straight line. This bow-string effect of the flexor tendons does not begin until the body is in advance of the vertical line and reaches its maximum at the end of the step. Pressure increases the length and breadth of the foot at the first part of every stride, through the yielding of the arch and the spreading of the structures, while swelling occurs as the result of long marches. The greater spreading occurs in the toes, the ball widening 6 to 12 mm., the instep stni less, and the heel only flattening to meet and adapt itself to the supporting surface. Fer^ found that, as a result of long marches un- 314 THEORY AND PEACTICE OF MILITARY HYGIENE. Fig. 109.— The Normal Foot and Foot-print. der heavy equipment, the plantar arch tends to become obliterated, with resulting temporary flat-footedness. In dealing with the feet of the soldiers, these may be regarded as being physically a select class from which at the outset many common abnor- malities are excluded, although most feet are more or less deformed by the custom of shoe wearing. As a re- sult of the pressure of ordinary shoes, a line drawn from the centre of the heel to the tip of the great toe will usually not cut the latter, but will pass through the third metatarsal, practically dividiag the foot into halves and depriving the ianer aspect of the leverage of the great toe, which has been displaced toward the centre. This toe may be semi- dislocated, often with the production of an inflammation in the joint, while its nail, turned down by pres- sure, is prone to grow into the flesh. The second and third toes, pressed together, are raised up, and examination of the sole of the foot shows only the third, fourth and great toes. Through pressure the toes are atrophied and deformed, loosing their rounded appearance and becoming asymmetri- cal and prismatic. If the shoe is too short they are retracted and take on the appearance of "hammer toes," which deformation gives great pain and unfits for marching. The tarsal bones are often deformed and present exostoses. The ordinary last upon which the issue shoe is made does not make provision for the com- paratively large size of the great toe, especially over the joint, is not suffi- ciently full over the other toes, and the upper leather over the heel and tendo AchOlis is cut too straight; hence it is at these points that ex- coriations and blisters most frequently occur. Deformities of the feet which are not very great are overcome by the use of rational shoes and need not be considered as necessarily a bar to enlistment. Soldiers, if left to themselves, are prone to draw shoes too short and narrow for their weighted feet, and the officer witnessing the issue should always pay particular attention to the selection made. It would be of ad- vantage if all shoes drawn were put on by the men immediately on return- ing to barracks, and their fit verified by the company commander before actual use. In fitting the shoe, one-tenth should be allowed in length and Fig. no.— Delormltles of Feet Resulting from Bad Shoes. MILITAEY CLOTHING AND EQUIPMENT. 315 slightly less in breadth for the expansion of the foot in locomotion. Zie- gler fixes the necessary excess of length at 15 to 20 millimeters. The carriage of an extra pair of shoes during campaign is a severe tax on the energies of the soldier, and it is a much-mooted question whether it is not advisable entirely to do away with this practice and trust to issues in the field from time to time, as opportunity permits, to re- place deficiencies. Such an ar- rangement, however, would also do away with one of the most efficaci- ous methods of preventing injury to the feet by marching; namely, the use of two pairs of shoes in daily rotation, by which relief is afforded through the temporary removal of pressure from galled places and its transference to other less sensitive parts. During hard campaign, with constant marching, under usual con- ditions of moisture and roughness of roads, a pair of shoes may be ex- pected to last about two months, and be sufficient, with light repairs, for a journey of six hundred miles over ordinary terrain. It is of the greatest importance that shoes which are new and stiff should be carefully suppled and broken in before being used on the march, since otherwise injury to the feet is almost certain to result. Such footgear should be soaked in water until every part is pliable, donned while wet over a heavy pair of socks and used for a walk of several hours. They will be found comfortable from the start, and at the end of that time will have acquired the exact shape of the feet. The shoes should then be removed, tightly packed with dry oats and set aside in a cool place so as not to dry too rapidly. When finally dried, the seams should be coated with molten wax to protect the thread, without removing the oats, and the whole outside should be given a coat of neatsfoot or cod- liver oil, repeating several times, and finally completing the process with some > water-proofing dressing. The oats are then shaken out, and the shoes will be found to be comfortable, damp-proof and durable, since the sweUing of the oats prevents shrinkage and no last can mould the inside of the shoe like the foot itself. Shoes which have been kept long in store become hard and inflexible, to prevent which they should, from time to time, be well gone over with an oiled rag. Wet shoes are heavy, liable to chafe the feet and readily lose their Fig. 111.— Eadiograph of Foot of Soldier, showing de- formity of toes and irritation exostoses due to bad sboes. 316 THEORY AND PRACTICE OP MILITARY HYGIENE. shape ; and the military shoe, while permeable to air, should not readily admit water. To assist in keeping out dampness it has been suggested that a layer of gutta percha be put on the upper part of the sole before it is sewn in place, but this is undesirable on accoimt of the retention of the perspiration which is thus caused. The uppers should in aU instances be waterproofed; this procedure not only ensuring dryness of the feet, but also suppling of the leather and rendering it more durable and readily cleansed. An excellent waterproof paste, which does not prevent the blackening of shoes, is composed as follows : Tallow 6 parts. Wax 2 " Linseed oil 2 parts. Venice turpentine 2 " This should be applied slightly warm. Thomas' preparation is similar, containing: Mutton tallow 6 parts. Yellow wax 1 " Neatsfoot oil 1 part. Venice turpentine 1 " Paraffine 1 " In these formulae the wax and paraffine are undesirable, since they iu- terfere with the dissipation of perspiration from the feet. Salquin recom- mends the use of the fat of the horse as being best of all; the writer has used wool-fat successfully. In the Prench army a mixture of three parts of mutton tallow to seven parts of neatsf oot oil is employed ; the proportion of tallow being slightly diminished in cold weather. Tanners use a mix- ture of mutton taUow, cod-liver oO., and a little potassium, this being worked in with a cloth and the aid of gentle heat. In the absence of the issue of any special preparation for this purpose, old soldiers are careful to frequently rub their shoes, previously warmed, with bits of fat bacon from which the salt has been dissolved, this increasing the impermeabUity and pliability of the shoe. Shoes thus treated, however, soon acquire a bad odor and attract flies in hot weather, and the rancid fat is said to cause rotting of the thread. Shoe blacking, as generally em- ployed, contaias a certaia amount of sulphuric acid, which induces drying and de- terioration of the leather and predisposes to cracking, the rotting of stitches and the entrance of water. Hence the military shoe should pref- erably be greased rather than blackened, especially since the blacking of shoes inter- feres with the evaporation of perspiration. To avoid the necessity of blacking the shoes, with its several disadvantages, the boots issued in the German army are now made of fail- leather. Shoes of this character, as issued with our khaki uniforms, have been much appreciated. The United States army shoe, as adopted in 1898, appears to be ex- cellent and satisfactorily to fill the needs of the military service. The vamp is made of calfsldn, and the top and tongue of kangaroo calf. Fig. 112.-1111116(3 states ArmyEegulation Shoe. MILITAKY CLOTHING AND EQUIPMENT. 317 Fig. 113.— United States Army Barrack Shoe. boarded and of uniform thickness. The side lining is the same material as the vamp, while the upper lining is of shoe drillmg. The outsoles, top piece and heel lifts are required to be cut from best quality hides weigh- ing eighteen to twenty-six pounds to the side. The shoe is hand-sewed with silk and Mnen thread, the inseam being covered by a welt taken out of the insole to protect the seam and make it level for the wearer. The outsole, thoroughly ham- mered, is grooved one-six- teenth of an inch to countersink the stitching, and sewed with eight and one- half stitches to the inch. The shoe is issued in eight sizes and four widths; the weight two and one-half pounds per pair. This shoe is constructed of ex- cellent material and well answers the purpose for which it is intended. Constant watchfulness on the part of quartermasters is necessary to keep the quality of leather used up to the proper standard. AH leather must have the entire thickness of the hide, as the middle portion is fibrous, absorbent and tough, and cannot be permanently reduced to a smooth sur- face. When subjected to hard wear it soon becomes rough and cloth-like in appearance. A too cheap shoe is never an economy, and footgear pegged or poorly stitched, whose absorbent soles almost fall apart upon ex- posure to wet, are plainly always to be avoided. Barrack shoes are issued for use in garrison when not on duty, and are much lighter and more comfortable than the leather shoe for this purpose. They are made with uppers of fifteen-ounce brown cotton duck, the toe and top of vamp being made of russet-colored calfskin. In the British service a stout water-proof slipper, and ia the Austrian and Ger- man armies a low shoe, forms part of the field equipment of the soldier and is intended for use in the camp after conclusion of the march. This practice does not seem to have any positive advantage over the carrying of a stouter and heavier shoe, since excellent results can be obtained by changing the ordinary shoes and stockings after the march, the differ- ence in weight being of little importance when com- pared with the military advantage of having a second marching shoe always available. In our mounted service a riding boot, issued in three widths and eight sizes, weighing about four and one-half pounds, forms part of the uniform of the sol- dier. This boot is well made, but is comfortable only for mounted use and is very liable to chafe when walk- ing. If loose-fitting, it affords no support to the ankle, and the liability to excoriation is proportionately in- creased. If snug, it is not easily put on or taken off, and if the leather be wet or shnmken, the stocking damp or the foot swollen, the former action is at times impossible. Under all circumstances the boot gives an insecure footing on a grassy surface, while it forms an insufficient protection in cold weather and is uncomfortably warm in hot climates. If boots must be worn in Fig. 114. — Cavalry Boot. 318 THEOEY AND PKACTICE OF MILITARY HYGIENE. Fig. 115.— Low Shoe Used In the Italian Anny. the future they should be short, pliable and light — ^but their use, together with the helmet and dress uniform, should preferably be abandoned. All mounted troops spend more time on foot than in the saddle, and since the ■Civil War our cavalry has fought dismounted. Hence it is only logical that the footgear of the cavalryman should be such as would enable him readily to march or perform any other duty when dismounted through acci- dent or design, and for this purpose no better combination than the infan- try shoe and long canvas legging can be debased. For purposes of parade a detachable leather leg, with stiff brace, might be worn with the shoe; thus giving all the effect of the boot and still avoiding a large proportion of its disadvantages. The footgear worn in different foreign armies varies greatly. In the Greek army a foot-covering similar to the buskin or high moccasin is worn. The Italian and Belgian soldier wears a low shoe and gaiter of the style discarded in France several years ago. The Spanish army in garrison uses laced leather shoes — but in the field it is supplied with sandals having rope soles, the latter rapidly wearing out and being of but little protection in mud, water or snow. In the British service a high laced leather shoe, with leather leggings, is worn. In the French army the " brodequin " or modified shoe has recently been adopted and gives excellent satisfaction ; footgear of this type being worn also by the troops of Austria, Switzerland and Turkey. In the German and Eussian services the soldier wears a boot ; this having obvious advantages in rain or snow, but possessing also many of the defects above noted for our cavalry boots. The Eussian boot is also higher than would seem to be de- sirable, reaching to just below the knee. The Blanket. — Excellent gray blan- kets are issued to troops, and of these each man possesses at least one. The specifications require that this blanket be made of long staple wool, free from shoddy, re-worked wool or cotton, and capable of bearing a strain of not less than thirty pounds per inch without tear- ing. The blanket is seven feet long and five feet six inches wide, and is required to weigh not less than five pounds. When in the field, and circumstances require it, an extra blanket for each two infantrymen may be carried on the wagons if transportation be ample. Should bad weather render it necessary, each mounted soldier may make use of his saddle blanket in addition to the one carried for his own protec- tion and comfort. Where used alone, the blanket may advantageously be converted into a sleeping-bag by sewing up one end and continuing the proc- ess half way up the side. The writer has found that the best plan for cold weather is for two men to sleep together, spreadiag their blankets lengthwise in such a way that the overlapping longitudinal edge of one corresponds with the middle line of the other. The men lie down close to each other Fig. 116.— French Brodequin. MILITARY CLOTHING AND EQUIPMENT. 319 in the centre of these blankets, and by pulling the free ends of the blankets over them convert the latter flito a sleeping-bag having a double thick- ness above and below. The open end at the foot is closed by lifting it up by the feet when the men are in position and turning in the upper edge. The feet rest on this edge, and their weight holds it in position, making the sleeping-bag wind-proof. Where this method is frequently employed it is well to work a small buttonhole in the comer of each blanket and sew a button at each end of the horizontal bisecting line more securely to fasten the blankets in position. The blanket, like the overcoat, should always be water-proofed for better protection against damp ground or sur- face moisture. When once wet the non-waterproofed blanket is uncom- fortable at night and burdensome by day, and frequently cannot be dried in the field during a period of rainy weather. The rubber sheet serves an excellent purpose in protecting the sleeping soldier from soil moisture. It is six feet long and three feet nine inches in breadth, and weighs two and one-half pounds. It is furnished with brass grommets so situated as to enable several of the water-proof sections to be joined, or to permit its use for the protection of the person of the soldier in camp or on the march during rainy weather. For ordinary use the rubber blanket may conveniently be replaced by the poncho ; this hav- ing a central perforation which passes over the head and retains it in posi- tion without' assistance from the hands. It affords excellent protection from rain during the march, and has the great advantage of not interfering to any great degree with the circulation of air. Where the ordinary cloth- ing is properly water-proofed according to one of the methods already de- tailed, however, the use of ponchos and rubber blankets can be very well dispensed with, and a saving thus made in the weight carried by the soldier. Ponchos and rubber blankets are issued gratuitously and are not charged against the soldier unless lost or destroyed by his neglect. II. EaUIPMENT. Transportation upon the person of such articles as are considered neces- sary for the independence of the modern soldier in the field, is to be ac- complished only with great personal discomfort and fatigue, and often by the expenditure of so much vital force as to seriously affect efiiciency and health. Weight. — The United States foot-soldier is required to carry in the field, besides the clothing worn on the person, the arms and ammunition, the canteen, the ration and the utensils for its preparation. To this may be added the change of shoes and underclothing, the blanket, poncho and shelter-tent half. With small columns these latter articles are generally transported in the wagons, but with large commands each man must carry his own. How this may be done without undue discomfort and fatigue to the soldier, and how the present burden may be properly reduced, are problems important from the tactical as weU as the hygienic standpoint which are as yet awaiting satisfactory solution. 320 THEOEY AND PRACTICE OF MILITARY HYGIENE. Outside the armament and eqmpment,^the weight carried by the indi- vidual naturally depends upon climate, season and the number of rations which it is required to transport. In hot weather the overcoat and heavy clothing are obviously unnecessary, while in dry climates the rubber blan- ket and even the shelter-tent may often be dispensed with to advantage. While the determination of the articles to be borne by the soldier in the field has, in the past, been left largely to the commanding officer in each individual instance or emergency, it is probable that only in rare instances — as in a winter campaign in a cold olimate, when transporta- tion is deficient — will the maximum outfit authorized by regulations be carried. It is not possible to state in exact figures the burden to be transported by the individual — since the weight of the clothing varies according as the articles are wet or dry and also with the height and size of the wearer — but the maximum weight which may be carried under ordinary conditions can be considered to be made up as follows : Apparel Worn on the Person. Pounds. Ounces. Campaign hat .' — 5 Overcoat 6 6.75 Blouse 2 1 Knit drawers — 14.75 Trousers 3 .50 Suspenders — 2.50 Flannel shirt 1 3 Knit undershirt 1 3 Stockings, woolen — 4.75 Gloves, fur — 10 Shoes 3 7 Leggings — 8.50 Total 18 1.35 Armament and Equipment. Pounds. Ounces. Rifle 9 Gun sling — Bayonet — Bayonet scabbard — Cartridge belt, woven 1 Cartridges, 100 6 Blanket bag 1 Blanket bag, shoulder straps, pair 3 Blanket bag, coat straps, pair 1 Canteen — Canteen strap — Haversack '. , 1 Haversack strap — Tin cup — Meat can — Knife _ Fork _ Spoon — Total 28 11 5.50 5.25 15 8 4 4 10 1 14 14.75 6 6.50 6.35 14.75 2.12 3.13 1.50 MILITAEY CLOTHING AUB EQUIPMENT. 321 Equipage and Additional Clothing Caeeied by the Soldier. Poundj. Ounces. Drawers 14.75 Undershirt ' [\ /_ i 2 Flannel shirt 1 3 Stockings [[ 4 75 Towel ......'.....'.'..... 3 Shoes 2 7 Trousers '.'.'..'.'.'.. 2 0.50 Poncho 2 13 Blanket 5 Shelter-tent half, with poles and pins 3 Total 18 10 Eations which may be Carried by the Soldier (Three Days). Pounds. Ounces. Bacon 2 4 Hard bread 3 Coffee, roasted — 4 Sugar — 7 Salt^ : _ 2 Water carried in canteen (full) 2 12 Total "9 ~0 Summary. Pounds. Ounces. Clothing worn on person 18 1.25 Arms and equipment 37 12 Rations, three days 9 Equipage and additional clothing 18 15 73 14.25 To this may be added the personal accessories, such as soap, comb, tobacco, matches, pocket knife and money, weighing approximately one pound, making seventy-four pounds fourteen and one-fourth ounces the maximum allowance to be carried by the soldier. According to Kirschner, the maximum weights to be carried by the infantrymen of different foreign armies, in 1893, were as follows: Kilograms. Pounds. Italy 33.000 73^ Germany 83.427 71^ Switzerland 30.375 66f France 39.555 65 Russia 39.506 65 Austria 39.480 64* England 38.633 63 Belgium 28.000 61f Since these figures were given it is understood that the weight of the equipment in the French and German armies has been gradually reduced, through the omission and lightening of articles and the use of aluminum, to 26 kilograms in both instances. From the above figures it requires no argument to demonstrate the fact that the weight to be carried by the soldier in nearly all coimtries is in excess of the practical as weU as the theoretical maximum, and that fur- 21 322 THEORY AND PRACTICE OF MILITARY HYGIENE. further reduction is desirable for hygienic as well as tactical reasons. Heavily loaded troops can march neither rapidly nor to any great distance, and the aggregate strength is proportionately weakened by the carriage of every superfluous article ; for the men who do the fighting are those who keep well up in the ranks. The carryiag of the equipment was estimated by Lewal to deprive the soldier of one-third of his mobUity; he believiug that the traversing by the French soldier of 40 kilometers in heavy march- ing order entailed the expenditure of as much energy as a march of 60 kilometers without such burden. Thurnwald states that the soldier should not carry a burden greater than one -third of his own weight if it is desired that he should maintain reasonable freedom of action on the march and in battle. Siace many young soldiers do not weigh more than 50 to 60 kilograms (130 to 135 pounds), he estimates that the total weight of the clothing and equipments should not exceed 20 kilograms (45 pounds). According to Laveran, experiments made recently in Germany with marches of 25 to 28 kilometers and weights of 22 to 31 kilograms, under varying conditions of temperature, showed that with a burden not greater than 22 kilograms and a distance not greater^ than 25 to 28 kilometers, such a march in an average temperature might be considered purely as salutary exercise. In hot weather these same conditions gave rise to un- favorable symptoms ; which, however, disappeared after a few hours' rest, without bad results. With a weight of 27 kilograms, during marches of a similar length, if the weather was cool and favorable no bad effects were noted, but if, on the contrary, the march was made in hot weather, very serious symptoms resulted. These experiments showed that a weight of 31 kilograms (68 pounds) is much too great to be carried under any cir- cumstances. Laveran places a weight of 27 kilograms (59^ pounds) as the maximum burden for marches of 22 to 28 kilometers during warm weather in temperate climates. These figures would seem to be too high, and for such conditions anything over 50 pounds is probably excessive. Prolonged marching under too great burden has been found to induce a gradual weakening of the constitution of the soldier, analogous to the lassitude and loss of muscular tone observed in over-trained athletes, and this systematic depression plays an important part in favoring susceptibility to infectious disease. It is a matter of common knowledge in European armies that increase in the sick-rate follows the autumn manoeuvers ; this being largely attributed to the more ready infection depending upon the exhaustion following the severe marching under heavy equipment which the troops are forced to perform. Reduction of Weight. — ^Napoleon believed in reducing the equip- ment as much as possible, but named the weapon, cartridges, knapsack, four days' rations and the pioneer's tools as the five things which should never be separated from the soldier. As to additional articles, he believed that the soldier in the field could do well with a spare shirt, extra pair of .shoes, stock and kerchief comprising his equipment. At present, such an ^outfit would be regarded as wholly insuflSicient. Where the soldier carries his own equipment, the multiplication of •articles for his comfort or efficiency is highly inadvisable, since, beyond a certain point, the inconvenience of weight far overbalances the advantages of possession. The allowance of the soldier, while containing the neces- MILITAEY CLOTHING AND EQUIPMENT. 323 saries, should not include a single article not absolutely required; the ten- dency properly being to diminish the equipment, both in weight and num- ber of parts, rather than to iacrease it. When rapid or forced marches are required, the soldier will usually march with no burden except the cloth- ing worn on the person, the armament and necessary rations. The weight of the latter should be reduced where possible by the use of emergency rations, and these may profitably be transported by the soldier only when the necessity for their possession is imminent; at which time they should be served out from the wagon train or depot. In reducing the weight of the equipment of the United States soldier the extra pair of trousers may advantageously be removed from the Kst of articles already given. The carriage of an additional pair of shoes is a severe tax on the strength of the soldier, and, where communication with the base of supplies is excellent, they, too, may perhaps be subtracted from the burden to be carried. The poncho may frequently be omitted, particu- larly if the outer clothiag has been water-proofed. The overcoat is neces- sary only in cold climates and for about one-third of the year, and the same applies to hea'S'y-weight clothing and underclothiag. This places the minimum weight to be carried by the soldier in the field, in temperate climates, as follows : Pounds. Ounces. Clothing on the person 10 — Armament and ammunition, 100 rounds 18 10 CarrjMng apparatus (exclusive of blanket bag) 4 6 Water and rations for one day 3 8 Blanket 5 — Shelter-tent (without poles or pins) 2 8 Undershirt 1 — Overshirt 1 — Drawers and stockings 1 — Small articles 1 — Total 48 — Or, less the ordinary clothing, about thirty-eight or thirty-nine pounds. While this is not a heavy weight to lift, it is certainly a very heavy weight to carry for a day's journey of fifteen to eighteen miles, and yet must be considered as light when compared with the usual equipment car- ried by the soldiers of foreign nations. With the allowance as enumerated above the soldier will be comfortable in warm and dry seasons, and need suffer no great hardship even during comparatively inclement weather. The further decrease of the clothing and equipment to thirty-seven pounds is possible ; but this necessitates the abandonment of aU but the clothing worn on the person, the armament, ammunition and rations. Such reduc- tion, however, is rarely advisable from a tactical point of view and never from that of hygiene, since, when deprived of his blanket roU, the soldier is exposed to aJl the vicissitudes save that of hunger, and even under the best of circumstances cannot long maintain his military existence. On this accoimt it is dangerous to abandon even temporarily the equipment on going into action, since, if defeated and forced to retreat, disorganization the more certainly follows. This, however, is one of the fortimes of war which military commanders wOl probably continue to hazard. Diminution in the number of articles Composing the equipment, if ex- 324 THEOEY AND PRACTICE OF MILITARY HYGIENE. tra clothing is to be carried, seems scarcely possible under present condi- tions, particularly in cold weather. For reduction of weight the next most promising field lies in the substitution of aluminum for other metals wher- ever possible, this readily permitting a decrease of weight amounting to about two pounds. Such a possible reduction, though at first thought ap- parently of but trifling importance, would nevertheless conduce greatly to the comfort and efficiency of the soldier — for two pounds carried twenty miles implies the expenditure of energy equal to that required to transport forty pounds through one mile. It should not be forgotten, however, in this connection, that the adoption of a small-caliber rifle, by which the weight of the individual cartridge was reduced, was hailed with delight by the tacticians, who, instead of regarding the reduction in weight as a gain in efficiency of the soldier, proceeded to bring up the burden to its original weight by more than doubling the amount of ammunition to be transported. Hence it is not improbable that the accomplishment of further reduction in weight would simply serve as a pretext for the addi- tion of other articles, the carriage of which by the soldier is at present confessedly impossible. The French have endeavored to reduce weight by abolishing individual camp utensils and issuing somewhat larger ones to each group of four or five men. This plan, while of advantage in a service where soups and stews form the chief food of the soldier, and where bulky kettles are consequently required, would obviously not be advisable in con- nection with a ration composed as is that of our army. •■ In considering the reduction of the equipment, it is well to remember that the soldier, particularly the recruit, starts out on campaign with the fuU authorized allowance, including duplicates of most garments, and is also prone to add various smaller articles which are fancied to be neces- sary to comfort. These latter should be carefully eliminated by inspection of the outfit before taking the field, and the soldier restricted to the official allowance ; the latter also being advantageously diminished when circum- stances warrant the removal of such articles as may not appear to be essen- tial. With hard marching, however, the soldier is apt to take the other extreme and lighten his load at the expense of even the more essential articles, trusting to good fortune to supply the deficiencies thereby created. This tendency, like that of overloading, is a marked characteristic of raw or ill-disciplined troops and should always be rigorously repressed. Disposition of the Equipment. — The greatest care is necessary in adjusting the burden of the infantry soldier, common experience showing that the transportation of the equipment is more or less fatiguing and in- jurious as it is carried in one or another manner. In practice, it is prob- ably not so much the actual weight as it is the arrangement of the effects which is oppressive to the soldier. The effect of heavy burdens, tight clothing and poorly distributed and disposed equipment in the production of heart-strain, as noted elsewhere, has long been understood^ — the mode of action being analyzed by Taylor as follows : The tightly buttoned coat, cartridge belt and gathered trousers compress the waist and thorax, and thus impair the movements of the dia- phragm and of costal expansion. The weight of the gun and equipment holds the shoulders back, impedes motion of the upper portion of the chest, and with' this arrest of the respiration there is an impairment of the circu- MILITARY CLOTHING AND EQUIPMENT. 325 : Fig. 145.— Hospital Tent. up the wall in pleasant weather, while the same number of foot-stops en- able the wall to be pegged closely to the ground. The entrances, front and rear, are guarded by broad lapels which can be snugly drawn together by means of fom- door fasfenings and an equal number of grommets. If necessary, each half of the door can be thrown back to expose the interior, while two or more tents can be joined end to end and thrown into a single ward under a continuous covering. When this is done, however, the ven- tilation is very poor, since the only openings for the renewal of air are in the canvas closing in the ends of the ward. Thus it is apparent that pro- vision for ventilation in a ward of eight or ten tents is no greater than it is in a single tent ; and as a result the air becomes so foul that it is gener- ally necessary to loop up the walls, with its accompaniment of glare, flies, dust and outside annoyances. Where a number of tents are thus pitched end to end, entrance and egress of nurses and patients can be had only at the ends of the ward, with great resulting annoyance to the sick in the tents near the extremities, especially if the ward be floored. It is there- fore apparent that, where tents of this model are used, the hospital wards should be made as small as possible; preferably being composed of no more 362 THEOEY AND PEACTICE OF MILITAEY HYGIENE. than three or four tent units. The hospital tent is provided with a fly of ten-ounce cotton duck, having a length of 21 feet 6 inches and a width of 14 feet. To properly pitch this tent requires the use of 18 pins 24 inches long and 28 pins 16 inches long. This tent, originally expected to accommodate eight to ten patients, has had its capacity for many years officially limited to six occupants. Such allowance affords 35 feet of floor space and 233 cubic feet of air space to each inmate ; an amount which may be considered as usually sufficient for temperate climates under conditions prevailing in the field. Willie the use of the hospital tent for other than hospital purposes has been long forbidden, its employment was found necessary for the shelter of troops in the occupation of Cuba ; it proving more suitable for a tropical climate than either the common or conical waU. tent. The allowance of six men to each tent was soon reduced to four in the tropics — thus giving each soldier 52 square feet of floor space. The issue of one hospital tent to each corps, division or brigade headquarters has also been recently au- thorized. For all conditions of field service and varying climate, wherever tentage of such size and character can be employed, the hospital tent has ^-^'^^'Z-iS^-i^''^ - -■^^- --„ Fig. 146.— Method of Pitching Hospital Tents on Frames to Form a Ward. been shown by long experience to be a generally useful, convenient and hygienic shelter ; being surpassed only by the modification devised by the writer, as described in a subsequent' chapter. In semi-permanent tent hospitals, and where the hospital tent is used for the shelter of troops, the tents are frequently stretched over wooden frames ; the guy ropes preferably being tied to a single bar, parallel to each side, in lieu of tent pins. This arrangement gives far greater stability, and at the same time economizes space between tents and facilitates policing of the camp space through absence of the pegs and long guy ropes. It has the serious drawback, however, of converting a movable into a fixed shelter, largely preventing proper sunning and aSration of the tent site and increas- ing the dangers of soil pollution. It is scarcely a question whether the advantages of the use of frames are not more than counterbalajiced by the disadvantages — for men under canvas can be kept healthy only by frequent changes of locality, and where sick are under treatment the rapid pollution of soil is inevitable. Tentage of Foreign Armies. — This subject, though of great magni- tude, can receive only brief notice. The " bell " tent used in the British army has a general appearance similar to that of our conical wall tent, of which it is practically a smaller representative. The base has a diameter of 12 feet 6 inches, while our conical wall tent has a diameter 4 feet greater; but the height of both is the same, 10 feet. The "bell " tent has a ground space of 123 square feet and an air space of 492 cubic feet. It is made of linen canvas or cotton duck, and weighs, all told, about 72 CAMP SITES AND CAMPS. 363 pounds. The "bell " tent is intended to hold from twelve to sixteen men; but this has at times been increased to eighteen or twenty. Ventilation is very imperfectly carried on through a few small protected apertures near the top — there formerly beiug no provision whatever for such purpose. The English hospital marquee is two-poled, with double canvas. It is somewhat similar in appearance to our own hospital tent, but is much larger. It has a length of 30 feet, breadth of 15 feet, height' of sides of 5 feet, height to ridge of 15 feet, a ground area of 385 square feet and an air space of 3,336 cubic feet. This tent is intended to accommodate eight patients and is fairly well provided with facilities for ventilation. Small circular tents, accommodating four patients each, form a recent addition to the hospital equipment. In India the British troops use various kinds of tents ; several of these being provided with double flies for greater cool- ness and protection from the sim. The French marabout or service tent is also somewhat similar in ap- pearance to our conical wall tent. Its diameter at the base is 6 meters, while its height is 2 meters. It has a capacity of 30 cubic meters and is expected to shelter sixteen men. The French hospital tent in general use consists of an ogival frame, according to Toilet's principle, covered with a double envelope, the outer casing being of linen and the inner of cotton fabric — the latter is rendered non-inflammable by chemical treatment. It is 15 meters long, 5 meters wide and 5 meters high, and is intended to accom- modate sixteen men, to each of whom it furnishes 11.5 cubic meters of air space. The " tortoise " tent is also used for field hospitals, this being merely canvas stretched over a wagon, which forms its central support. This tent has very many disadvantages and few merits. In the German army two kinds of tents are in use. The tent for in- fantry is a conical wall tent 12 feet high and 15 feet in diameter; provid- ing 70 cubic feet of air space to each of its fifteen occupants. The tent used in the mounted service is wedge-shaped, one end being left open, and much resembles a large shelter-tent. The German hospital tent in 29|- feet long, 24^ feet broad and 13f feet high. It is divided by curtains into three parts, a central one for sick and two smaller apartments for attendants and supplies. Each tent contains only six patients, though double that number might be accommodated. Tents are rarely used in the German army, and the cantonment system is practiced almost exclu- sively during manoeuvers. The Eussian infantry tent is 14 feet square and 7 feet high to the slope. There is a central pole, with four corner supports. It is intended for four- teen men, but is Usually occupied by a less number. The floor space is largely taken up by a bench, 1^ feet broad, aroimd the sides, together with a central rack for rifles. This tent is not intended for use during campaign, when recourse is had to the shelter-tent alone, and is used only in camps of some permanency. In the Spanish army small marquee tents are used by ofiicers; the men using conical tents. The latter are known as Nos. 1, 2 and 3. No. 1 has a height of 3.30 meters, a diameter at base of 6.39 meters and an official capacity of sixteen to twenty-four men. No. 2 is 2.96 meters high, has a diameter of 4.33 meters and accommodates ten to sixteen men. No. 3 has a height of 2.35 meters, a base of 3.12 meters and a capacity of four to eight men. The Austrian infantry tent 364 THEORY AND PEACTICE OF MILITARY HYGIENE. is similar to a large old-style shelter-tent, as used ia our service. It is wedge-shaped and both ends are left unprotected. It has a height of 4 meters and covers a ground space 7.90 meters long and 6.60 meters wide. Improvised Huts. — These, during war, afford a means of housing an army expeditiously. For purposes of warmth they are far better than tents for winter quarters, and may also be used during siege, blockade, or when troops are occupying a position which is intended to be held for a consid- erable period. This method of shelteriag troops by huts has been largely developed in our own service, particularly during the Civil War ; since, excepting during the Crimean struggle, the adoption of such a means of protection has rarely been found necessary in European armies. In size, the hut should be small rather than large, since the dangers re- sulting from soil pollution and the aggregation of large numbers of human beings are thus minimized. During the Crimean War, the huts built by the Allies were sufi&ciently large to accommodate from twelve to twenty- four men ; but four men, where possible, should form the unit of occupancy. Should large huts be employed, the accommodation may be calculated on the basis of not less than two running feet to each inmate, where only a single row of beds is intended. In the Spanish army the following pro- portions are officially required to be maintained in the construction of improvised huts : Number of men. Length, Interior, meters. Width, interior, meters. Height, meters. Number of men. Length, Interior, meters. Width, Interior, meters. Height, metere. 8 10 12 14 5.30 6.50 3.90 4.55 2.70 2.70 4.65 4.65 3.80 2.80 3.00 8.50 16 18 30 5.20 5.85 6.50 4.75 4.75 4.75 3.50 4.00 4.00 Huts should be separated by intervals considerably greater than is nec- essary in the case of tents ; since the amoimt of soil pollution is dependent upon density of population as well as duration of occupancy — and a change of site, so readily accomplished with the use of tentage, is not possible ,. 2.S0 ^ FIG. 147.— Transverse Section of Excavated Hut Used in the German Army. where fixed shelters are employed. Efforts to separate huts widely will usually be opposed by the desire of the commanding officer to possess a compact camp for convenience in handling his men; but huts should never be located nearer to each other than a distance equal to one and one- CAMP SITES AND CAMPS. 365 half times the height of the ridge. For all permanent camps or winter quarters, huts are best arranged in echelon. Underground habitations are warm, but are usually damp and always difi&cult of ventilation, and hence should never be employed where other protection is available. Even the banking of the sides of a surface hut Fig. 148.— Frame for Thatched Hut. should be avoided. In the British and German armies, however, many of the forms of winter huts recommended are wholly or partially below the sittface of the ground, and excavation by the soldier is still officially en- couraged. The materials of which improvised huts are made must necessarily vary according to the resources of the locality, and are usually brushwood, logs, straw, reeds, clay, turf or stones. The size of such habitations de- pends upon the material available for their construction as well as the number of men which they are intended to shelter ; but, as aheady stated, the unit of occupancy should be small. Huts for warm climates may be built by simply erecting a framework with skeleton roof; the latter being thatched with straw, reeds or other suitable material. Bark of trees, de- tached in large strips by beating with a fiat piece of wood, is excellent for the construction of walls and roofing. Bamboo has been much used in the British service for the construction of temporary shelters, and its employment for this purpose has given excellent satisfaction, notably in the Ashantee and Suakin ex- peditions and on the northeast frontier of India. In the several campaigns in the Soudan, huts were largely constructed of sun-baked bricks, their use giving excel- lent results ; but like the adobe huts, much used in our own southwest, they are leaky and damp in anything but a rainless cli- mate. According to Smart, one camp in Arizona, in existence for ten years, consisted of merely shelter-tent roofing over walls of wiUow-work, with a canopy of brushwood erected over the> whole to afford a better shade. In dry and moderate climates the walls of huts may be constructed of poles planted in the ground, or closely woven wicker-work daubed over '^T^^Wigmra^ft^^^iSSJi^^SE!^^ Fig. U9.— Method of Thatching. Missing Page Missing Page Missing Page Missing Page 370 THEORY AND PEACTICE OF MILITARY HYGIENE. been recommended that temporary shelters be sufficient to hold each twenty- eight men. The length suggested is 32 feet; breadth 16 feet; height to ridge 16 feet. Such a building affords 400 cubic feet of air space per man. Two such huts are to be placed end to end, with a single chimney between them — a petty economy not at all advisable, since such large structures should always be separated from each other by a distance equal to at least twice the height of the ridge. In warm climates, where troops are quartered in temporary frame bar- racks the roofing material is of the greatest importance. Metallic roofing renders buildings extremely hot; a fact unfortunately disregarded in the construction of our temporary barracks in Cuba, where corrugated iron was employed. Probably the best available material for such purposes, every- thing considered, is tarred paper. A convenient arrangement for winter quarters in a not too rigorous climate, combining the use of both tents and huts, was devised by Falk Fig. 156.— Falk's Arrangement for Winter Camps. and put into practice in the camp at Anniston, in 1898. In this plan the common wall tents in use were pitched in groups of three ; radiatiag from a central frame wooden cabin having a length and width of 8 feet 4 inches, or equal to the width of the tent. This buildiag was provided with four doorways ; three leadiog into the adjacent tents and closed by their canvas flaps, while the fourth opened into the company street and possessed a frame door. The central structure contained the stove and rifle racks, and afforded a comfortable lounging place for the men. This system effected a great saving in stoves, fuel and tentage ; the central cabins being erected at a cost of less than $3.00 each. Ventilation was said to have been good, while the tents, used only for sleeping purposes, could at all times be aired and their floors raised for the ventilation and cleanliness of the tent site. The only objection to the arrangement is one which applies as well to all fixed camps — ^the location could not be changed without implying the de- struction of the cabin itself. Portable Barracks. — Portable barracks, of which there are numerous varieties, are usually made of wooden or metallic frames covered with a special kind of felt protected by canvas. These buildings are all well ven- tilated by windows, flues, cross louvres and ridge ventilation, and, as a re- CAMP SITES AND CAMPS. 371 suit of careful investigation into their merits, the use of one or another model has been authorised in nearly every European service. The Ducker portable barrack, made in the United States, has a front- age of 17 feet and a depth of 33 feet. There are also front and rear annexes, 3 x 5.5 feet, used respectively for vestibule and toilet purposes. The building is constructed of double sections hinged together, each en- closing a cot, table and stool, and is set up by a locking device without the use of screws, nails or external appliances. Expert help is not required for its erection, and it is said that two or three men can prepare such a barrack for occupancy in three or four hours. Each section weighs about 50 pounds, and the whole building, when packed, occupies a space of about 900 cubic feet and weighs 2,500 pounds. The material employed in the construction consists of wood frames with panels of patent fiber board, protected on the outside with 8-ounce duck cemented to the panels. If desired, a canvas roof with fly may replace or screen the sectional roof. Fig. 157.— Section of Ducker PortaWe Barrack, Open. :^^*^-^'' ' Pio. 158.— Section of Ducker Barrack, Closed for Transportation. The building is excellently ventilated, possesses double walls to modify extremes of temperature, and allows 56 square feet of floor space to each of the ten occupants which it is planned to accommodate. The Doecker barrack is but little different in its essentials from the preceding. It is made in Denmark, and has been adopted for use in the armies of England, France, Germany, Austria, Denmark and Sweden — nearly every service requiring various changes in the original model bet- ter to suit local conditions. The type of the Doecker barrack used in the French army is 15 meters long, 5 meters wide and 5 meters high. It is intended for 16 occupants, to* each of which it gives 17 cubic meters (600 cubic feet) of air space. When packed, the building weighs 3,600 kilos (7,900 lbs.) and requires for its erection the labor of six men for one day. According to Laveran, one such barrack building can be carried in a single large wagon. The Berthon portable barracks are highly commended by Notter and Firth. This pattern has not, however, been adopted for use in the military service of any nation, and it is difficult to see exactly where its special 372 . THEOEY AND PRACTICE OF MILITARY HYGIENE. applicability to military conditions lies. The expense of this barrack is considerable. Portable buildings have also been invented by Toilet, Espitalier, Olive and others. While excellent service can undoubtedly be rendered by portable barracks under certain limited conditions, their value for the military ser- vice should not be highly estimated. It is evidently impossible, even under the best of circumstances, to house in this manner a large number of troops, even if first cost and comparative lack of durability did not in- terdict such action ; while in time of war their transportation in sufficient quantities would evidently become impossible. Frame barracks, well con- structed, are relatively inexpensive and are larger and more comfortable than portable barracks, and their erection is not a matter of great time or labor. Moreover, the latter cannot long withstand rough handling or being repeatedly put together and taken apart. Portable buildings, in the military service, would probably be of the greatest value in connection with Fig. 159.— External View of Duoker Portable Barrack. base hospitals, or during epidemics when hospital accommodations are in- sufficient. They nught also be of advantage for purposes of isolation, in connection with outbreaks of contagious disease during very cold weather. Permanent Camps of Instruction. — Nearly all the larger armies of the world maintain permanent camps of instruction, which are used by troops only during certain periods of the year, usually in the autumn. In the majority of these camps the troops occupy rough wooden buildings, and there is usually a system of sewerage and a piped water supply. In the British service, permanent camps of instruction are maintained at Aldershot and the Curragh ; the barracks being light frame structures with double walls and capable of accommodating twenty-five men each. In the French service, a summer camp was maintained at Boulogne fi-om 1803 to 1856, at which time it was transferred to Chalons, where a large number of frame pavilion barracks have been erected. Until recently the German army possessed no special places or facilities for encampment during the fall manoeuvers, the troops heretofore being billeted on the civil population. Eecently, however, a temporary camp has been constructed at Boeberitz capable of sheltering 6,000 men. The Russian army goes into camp for CAMP SITES AND CAMPS. 373 instruction each, summer at Moscow, Krasnoe-Selo and Varsovie — the troops living partially in frame barracks and partly under canvas. Italy maintains temporary camps of instruction at Fojano, San Morizio and other places ; and fixed encampments of this character are also maintained by Belgium and Denmark. Permanent camps of instruction have not been established in the past in our army, by reason of the small number of men composing the latter, and their dissemination over so wide an area as to render their annual concentration not only difficult but costly of accomplishment. It was also supposed that the practice march required to be performed each year by troops would give sufficient instruction in field service. Eecently, however, the necessity of having our of&cers familiar with the management of large bodies of troops has been emphasized, and the establishment of a permanent camp at some central point — as the Chickamauga National Park — ^has been strongly urged. If this be done, the location of the camp should be care- fully selected, and drained, sewered and piped as if for a post. Eoiigh but substantial buildings should be erected, suitable for warm weather, and facilities provided for the disposal of excreta and refuse by the most ap- proved methods. Should these precautions be neglected, annual outbreaks of enteric fever and other infectious diseases may be expected to occur among the troops under instruction. CHAPTER VIII. THE SANITARY ADMINISTEATION OF THE CAMP. The Camp Space. — In the establishment of the camp, troops should never pass over or form upon ground which is to be occupied by tents, since it is most important that this space should be kept clean and the turf unbroken. Baggage wagons, also, should be carefully driven in the inter- vals and not over the intended tent sites ; not alone for the same reason, but also because fouling of the gi-ound by horse urine and droppings is liable to occur while the camp equipment is being unloaded. After the camp has been established, no traffic of any kind should be allowed along its front or through the company streets, so as to limit the production of dust or mire as far as possible. The outlining of a general plan for grading and trenching a camp of any permanency should follow its location; the details being subject to modi- fication as a result of careful inspection of the camp area on the first rainy day, when the natural trend of the surface water can be accurately deter- mined. The work itself may be gradually done after more pressing duties have received attention. The drainage should preferably be toward the flank, away from the tents and kitchens. In permanent camps or winter quarters the trenches for the removal of storm water from the vicinity of the tents may be advantageously paved with pebbles. All surface drain- age from higher ground should be carefully intercepted and tiuned aside, and in camps of any permanency such depressions as are liable to retain water should be either filled up or drained. A hut or tent, even in presumably temporary encampments, is not ready for occupancy until protected agaiast invasion by storm water. For this purpose, with hospital or officers' tents, a trench having a width and depth of four or five inches is dug close to the wall in front and rear, and about four inches from the sides on each flank, corresponding to the lateral edges of the fly, banking the earth slightly so that no overflow can reach the interior. With the conical wall tent, the trench closely follows the canvas where it meets the ground. Such a trench, to be of value, re- quires an outlet ; and this should lead into a main trench or gutter of a size sufficient for the ready conduction of the rainfall from the company area. Within the limits of standing camps the construction of roads wiU. fre- quently be required, and this possible necessity should receive due con- sideration in the selection of the camp site. Pathways should be con- structed along the company streets — and these, together with those communicating with the sinks and kitchens, should be so gi-aded, drained or gravelled as to enable the men to avoid mud and water while in the performance of their routine duties. In many instances, elevated plank walks can be constructed ; or, in a wooded country, split logs may be used for a similar purpose. Where the soil is soft and an abundance of gravel THE SANITARY ADMINISTRATION OF THE CAMP. 375 can be procured, it is well to place a thin dressing of the latter material over a portion of the company street, and thus ensure a hard, dry area upon which the' men can assemble ia wet weather. In the temporary camps of mounted troops the position of the picket line is a matter of regulations ; but in standing encampments of large cav- alry commands the animals should preferably be located at a convenient distance outside the limits of the camp proper. The picket line should be carefully policed, particularly in warm weather, since flies find in horse droppings not only a food but a favorite medium upon which to deposit their eggs. Camps which are occupied for a short time only are generally healthful. This, however, is not the case, if troops remain on the same site for several weeks or months; and the sanitary officer should be fully alive to the necessity of fresh soil for tents, particularly with raw troops and a large command. In the French campaigns in Tunis it was often noted that the troops which remained longest in fixed camps furnished the largest pro- portion of sick — and experience has amply demonstrated that a camp which is not moved will ultimately become seriously infected. On the other hand, the evacuation of an infected site is of powerful assistance in bringing epidemics to an end. Gordon recommends that camp sites be changed every eight days; while Baudens considered that tents should never remain on the same site more than half that time, and in the German army, troops are not allowed to bivouac on the same spot more than twenty- four hours ; but the period during which a camp may be safely maintained on the same site is a matter which must evidently be largely regulated by circumstances. Whenever troops are vmder canvas, however, unless some military reason other than expense or inconvenience prevent, it is always desirable that camps should be moved at intervals of a week or ten days to a distance at least sufficient to clear the confines of the old encampment, without waiting until a general infection of the camp or soil has obviously been accomplished. It does not suffice merely to strike tents, though this, especially in sunny weather, is of much advantage — ^the camp site itself must be abandoned. Habitations, — G*rass in the tent area should always be cut short, or, in camps of a more permanent nature, pulled up by the roots. Under any circumstances, such grass is soon killed, and by its decomposition adds to the contamination of the tent atmosphere. The ground composing the floor of the tent should be well pounded to render it less permeable, and where wood ashes are available they are sometimes used as a top dressing. In the German army, if the soil be not considered of desirable character, the tent area is excavated to the depth of one foot, and the dirt so re- moved is replaced by gravel or ashes and watered and pounded imtil hard. In all camps of any permanency the flooring of the habitations conduces much to the comfort and cleanliness of troops. Such flooring, usually of planks, should be in sections of convenient si^e to permit of its removal for purposes of cleanliness and aeration, and shoidd be raised several inches from the groimd by the use of scantling or split logs. In the French army, cement floors have been used in the tents of standing camps and have been favorably reported upon. The ground included in the tent area is sUghtly excavated, the excavation filled with broken stone and the 376 THEORY AND PEACTICE OF MILITAEY HYGIENE. whole covered with a layer of cement. Earth should never be removed from the inside of tents or huts with a view of iucreasuig space, since such an excavation is nearly always damp and the occupants are more exposed to emanations from the soU. The danger of excavating the enclosed area was well shown in the Crimean War, when the troops were allowed to take such action in housing themselves; the sickness and death rate among troops occupying such shelters, notably the 79th Highlanders, being far greater than among troops living under other conditions. Sol- diers should always sleep above rather than below the surface of the grovmd. A certain amoimt of fresh air may filter its way through dry canvas ; but if the latter becomes wet, through rain or dew, the fiber sweUs to a considerable extent and the texture becomes practically impermeable. Hence no reliance should be placed upon renewing the air of the interior of the tent by any means except the use of ventilating apertures, properly located and of sufficient size. With the exception of the latest model conical wall tent our tentage may be considered to be fairly well aired as military tents go ; although with the former allowance of inmates for the common tent the atmosphere was frequently confined and disagreeable odors were marked. The excellent ventilation of the 1888 pattern of conical wall tent keeps the air constantly sweet and pure, no matter how large the number of occupants ; and the same is true of the tent devised by the writer, in which ventilation is so free that the inmates are practically in the open air. With even the best kind of tentage, however, except the pattern last mentioned, on account of the small allowance of air space afforded the men, the tent door is best left open except during wintry or inclement weather. The walls of tents should also be kept raised as much as possible ; and even at night the leeward side may often be looped up with advantage. In moderate weather the ventilation of tents is usually fairly free, but in winter the effort at the maintenance of warmth implies an attempt at the diminution of ventilation on the part of the soldier. In extremely hot weather, hospital or officers' wall tents may be better ventilated by slitting up a seam in the roof near the ridge, inserting a notched stick to keep the opening well spread, and thus permitting the efilux of heated air between the tent roof and the fly. Tents should never be banked up with earth for the sake of warmth, nor should the sod-cloth be covered with earth for the better exclusion of air currents. Clean, smooth stones may be used for the latter purpose if anything be necessary, but no more compact material shoiild be allowed. In the bivouac, or where shelter tents are used, open fires afford the only means of obtaining warmth. If kindled a few feet in front of the tent the interior is usually comfortably warmed, but if a strong wind is blow- ing such fires must be carefully located and watched. Fires built for heat- ing purposes should not be too large. If small they are more readily con- trolled as well as being much more economical of fuel, and if properly tended they radiate an ample amount of heat. The camp-fire is best built in Indian fashion, one end only of each stick being ignited and the pieces of wood being disposed like the spokes of a wheel. By pulling out or pushiQg in the fuel toward the centre, the fire may readily be made to die down or burn up more freely. With the conical wall tent, pattern of THE SANITAKY ADMINISTRATION OF THE CAMP. 377 1888, a small fire of this character may be kindled, in the absence of stoves, in the centre of the floor space, the smoke finding its way out through the ventilating aperture at the apex. The so-called California stove consists of an excavated fire-place in front of the tent, with a flue covered with earth and sod running imder the tent floor and connecting with a chiomey in the rear. The hot air and smoke are drafted through and warm the tent- — but it is difficult in prac- tice to prevent vitiation of the air in the tent by smoke and gases, and accidents from fire are naturally somewhat frequent. In stormy or very cold weather, tents are best heated by the use of the Sibley stove. This has the form of the frustrum of a cone and is made of malleable sheet iron. It has a height of 28 inches, a bottom circumfer- ence of 58 inches and a weight of about 19 lbs. Draft is provided by Fig. 160.— Arrangement of Stove and Chimney in New Model Conical Wall Tent. a triangular shaped vent at the bottom. Recent models of this stove are equipped with a spark arrester and cup shelf. This stove is capable of burning either wood or coal, while its small size and the small amount of iron used in its construction enable it to be rapidly cooled for removal and packing on breaking camp. It is a rapid and powerful heater, particularly where resinous or very dry wood is employed ; and hence the tent is usually overheated by the inexperienced through the use of too much fuel. As combustion of the fuel is rapid, such a fire requires constant replenishing for its maintenance. Usually the fire is ultimately permitted to die out during the night, except in the coldest weather, when the previously over- heated occupants of the tent are liable to become chilled. While this stove is particularly adapted for use in the conical wall tent, the hospital or other tents may be heated by its use — ^the pipe being bent in a double right angle and conducted outside the tent through a ventilating aperture. 378 THEORY AND PRACTICE OF MILITARY HYGIENE. Some tents have a hole punched through the roof, sufficiently large to ad- mit the passage of the stove pipe and lined with asbestos cloth, tin or zinc to prevent accidental conflagration through an over-heated stove pipe. When in use one corner of the tent fly is tied back so as to imcover the aperture. As a general thing it is inadvisable to mutilate the tent roof, and the rim of ziuc or tin around the aperture is necessarily soon bent and distorted. Where the collar around the pipe opening is made of asbestos it is obvious that the latter objections do not apply. A canvas flap may be sewed to the tent roof so as to cover the pipe opening when the stove is not in use. Improvised huts may be warmed by the use of stoves or open fire- places. The latter method is, however, preferable, since it also largely assists in the maiutenance of ventila- tion. In winter quarters, during the early part of the Civil War, the heating facilities varied greatly. Open fire-places were made of brick, stone, mud or sods, with chimneys of the same, with or without an additional draft made of boards, barrels, sticks and mud or hoUow logs — while habitations were frequently warmed by sheet iron stoves with or ^'°' ^^k^^wMfprotectingMa™** ^^"^ without pipes, open fires in the middle of large tents, or what was stiU. more objectionable, open kettles of embers from the kitchen fires. Toward the end of the war the employment of the open fire-place with a chimney of mud and sticks became the rule. A double thickness of canvas, one tent being pitched over another, is of excellent service in preventing extremes of inside temperat\ire. In the Sioux winter campaign of 1890 the officers making use of this arrangement had no difficulty in maintaining a comfortable warmth even in the blizzard weather of the northwest. The value of this device is officially recognized in the Russian army, tents made of double canvas throughout being issued for the use of officers; the hospital tents of the English, French and German armies are also of double material, the French tent being lined with woolen cloth for the attainment of greater equality of internal tem- perature. The same arrangement is also of great value in tenting in the tropics, since the heat of the solar rays is diminished by the air space between the double canvas. Observations made in Cuba, in 1899, showed a temperature in a wall tent without a fly of 89° F. At the same time the thermometer registered 87° F. in a tent with a single fly and 82° F. where one tent was pitched inside another and a fly stretched over all. Tent flies are of value in preventing leakage during hard rains, and in the dimiaution of the heating of the interior of the tent dm-ing hot weather. They should always form part of the canvas shelter of troops during summer or in tropical countries. In hot weather, a hospital or officers' tent is cooler if its fly be raised ten to fifteen inches at the four corners, by supporting it upon pointed stakes of sufficient length. In ex- periments made by the writer, the elevation of the tent fly in this manner, to the extent of one foot, lowered the inside temperature of the tent from THE SANITAEY ADMINISTRATION OF THE CAMP. 379 93° F. to 89° F. A tent fly spread in front of a tent of this pattern is an excellent protection against a hot sun — while the erection of leafy arbors above or in front of tents affords a grateful shade without interfering with air-currents. Lateral walls for such arbors, however, are in the way, impede ventilation and greatly increase the danger of fire. Tent ropes diminish in length on being moistened; and hence should be slackened to prevent the tent pins from being drawn, or the supports from breaking, if a heavy dew or rainfall is anticipated. Wlien dry, the ropes will require tightening to prevent flapping of the canvas, with the resulting annoyance of loosening or pulling out of the pegs. The tent pins should always be driven at a slight inclination toward the tent rather than at an angle away from it, since when so placed they hold much bet- ter in wet soil. In sandy places it is difficult to keep tents standing in a high wind, as the pegs draw; and in such instances, the guys may be fast- ened to stones or other heavy articles — or with small commands the In- dian method may be employed, the wagons being pushed between tents and the tent ropes fastened to the blocked wheels. Bushes may be buried in the sand, the branches pointing toward the tent and one stout bough projecting above the surface to which the rope can be fastened. This method is an excellent way of keeping tents erect, as the bush forms a species of anchor. With soil of such character, a flat stone or piece of wood should be placed under the tent pole to prevent it from being forced into the ground. Tent walls shoiild be looped up at all times during fair weather, so that the tent area may be dried and disinfected by the solar rays. Even in cold weather, if the weather be bright, the sides of the tent should be tied up during the absence of the occupants on drill or other duty. Tents should be taken down from time to time, spread open and the inside sunned ; or, as is customary in the English service, they may be roughly re-pitched on a new site and allowed to blow about freely in the wind be- fore being replaced on the original tent space. Tents should be struck and their enclosed area sunned at intervals of -three or four days, provided a change to a new camp area or fresh tent site be not practicable. In a properly arranged camp the intervals should always be sufficient to render possible the removal of the tent to a new site, previously unoccupied. Where huts are used, the doors and windows should be opened daily to permit of perflation and the entrance of sunlight, and the roof, if canvas, should be turned back. Beds and Bedding. — It may fairly be considered that the surface of the earth, imder usual conditions, is sufficiently damp to render sleeping upon it, without the interposition of some suitable protection, injurious to health. Hence the use of the rubber blanket, as a protection from soil dampness, is always to be requhed where opportimity is not afforded the men for raising their bodies above the level of the ground. Whenever a camp is to be occupied more than a single night, particularly if the site or weather be damp, the men should be encouraged to construct rude couches of poles, old boxes, barrels, brush or canvas, with a softer layer above of hay, straw, grass or twigs. Except in the absence of better material, green deciduous foliage should not be used for bedding; but pine, hemlock and spruce boughs make excellent and luxurious couches. 380 THEOEY AND PEACTICE OF MILITAEY HYGIENE. Unfortunately these soon part with, then: elastic properties and, when de- prived of a portion of their moisture, largely increase the ever-present dan- ger of fire. In the bivouac, where any choice is possible, it is better to spread the blankets on a spot which has been exposed to the sun than on a shaded and presumably damp locality. Under existing regulations, where mattresses are not supplied, each enlisted man id barracks is entitled to receive an allowance of thirty pounds of straw per month as bedding; and in camps of any permanency the issue of such a quantity of straw for this purpose would no doubt be authorized. In the .German army, each man is entitled to a bundle of straw at each bivouac, taken from the nearest stack. If thrown loosely on the ground duriug the day, along the walls of the tent, such straw or hay soon becomes damp and foul and by fermentation practically becomes a compost heap. Hence such material is best woven into sleeping mats of three or four inches' thickness; these being extremely comfortable, per- mitting a daily exposure to sun and air, and largely limiting that interfer- ence with proper police which the presence of loose straw can scarcely fail to iaduce. Straw mats are made as follows : The straw is twisted into ropes and passed around two rows of tent pegs driven into the ground, parallel to one another and two feet apart, thus forming the web. Other ropes are interlaced to form the woof, and an excellent mat may thus be made in a short time. Ordinarily each man should have two mats, one for the head and one for the legs ; but if a conical tent be used the mats are preferably single. Four men in a single day can readily make sufB.- FlG. 162.— First Step in Weaving Straw Mats. Fig. 163.— Straw Mat, Completed. cient mats for five times their number — two twisting and two weaving. Straw employed for bedding should be aired daily, and after being used for ten days or. a fortnight should be burned and replaced by a fresh supply. In camps of any permanency, troops are now supplied with a folding canvas cot of excellent pattern. This is very comfortable, and can readily be folded up for transportation into a small package about three feet long and weighing but fifteen pounds. The cot is very strong and durable and is much liked by the men. A fold of canvas at one end furnishes a space in which hay, branches or articles of clothing can be retained to form an excellent pillow. Cots of this character, like the other contents of the tent, THE SANITAEY ADMINISTEATION OF THE CAMP. 381 should be frequently sunned in the open air. When troops are quartered in huts or frame barracks the issue of canvas hammocks may at times be desirable, since they are comfortable, cleanly and removable when not in use ; with a resulting considerable increase of floor space. Blankets and bedding should be sunned and aired on each fair day — either by hanging on supports erected for the purpose or by spreading on the sunny side of the tent roof. The former plan is preferable, as it allows access of sunlight and air to both sides of the article. " Blankets are some- ^V^ T-'q» >\Sg^.S^ IiG. 164.— Folding Camp Cot used in the United States Service. times hung in the shade by troops. This is of comparatively little value from a sanitary standpoint, as it is the solar rays which are germicidal. The Excreta. — The preparation of the sinks at once upon the selec- tion of the camp site is of the first importance. It will not do to delay their construction until the tents have been pitched and other camp duties have been performed, but, after the water supply has been guarded, a spe- cial detail should be at once told off for the accomplishment of this pur- pose. The completion of the sink is to, be considered a matter of urgent necessity and not one of election, even if it is understood that the com- mand is to move on the following day. Such promptness of action will largely prevent the surface contamination which would otherwise inevi- tably follow; and which, under conditions of infectious disease, favorable humus and suitable climatic and topographical conditions, may render a locality unsafe for military occupancy even before the camp itself has been fairly established. Under certain military conditions, pending the construction of the latrines, a certain amount of surface pollution may become unavoidable, and under such circustances some carefully selected spot should be desig- nated for the reception of the dejecta ; due precautions being taken that all faecal material is covered with earth by a police party at the earliest op- portunity. The latrine accommodation provided in camp should be ample, since otherwise the health and comfort of troops are unfavorably influenced and it becomes impossible to prevent the surface of the ground from being fouled. Accommodation should be provided on a higher scale in the field than in barracks, and sufficient latrines should be constructed to seat at least ten per cent, of the troops. In the German army the seating capac- ity of the latrines is required to be in the proportion of sixteen places to each hundred men. The multiplication of sinks is undesirable, and with large commands the construction of a separate latrine for each company should not be permitted. One sink for each battalion of four hundred men is amply sufficient, and this may be expected to be fiUed up in from ten days to two weeks should the camp be fixed for that length of time. It 382 THEOEY AND PEACTICE OP MILITARY HYGIENE. will receive better attention than would several smaller latrines, and soil pollution is also more localized. The general location of latrines should depend upon their proximity to the various organizations of the cTommand, the length of time the camp is to stand, the direction of the prevailing winds and the position of the water supply. Their exact position should be determined by the officer in charge of the laying out of the camp ; since if left to the discretion of company officers they are liable to be so placed as to inconvenience troops of other organizations. They should, of course, be located so as to prevent possible contamination of the water supply ; and should be placed to leeward of the camp, or so that prevailing winds will not carry odors over company areas. It would seem superfluous to warn against locating the sink in such a position that it can be flooded by storm water from higher ground, yet such an error has frequently been made. Latrines should be as far re- moved from tents as is compatible with convenience. Under the regula- tions of 1863 this distance was set down as 150 paces; but a distance of 100 yards may be considered as sufficient for ordinary conditions. Ob- viously, the exact distance at which the latrine is located must often de- pend on circumstances. If too near to the tents it will be a source of annoyance; if too far, soil pollution is inevitable, for many men, particu- larly at night, or if affected with diarrhoea, may either wilfuUy or of ne- cessity defsecate before reaching the sink. To insist that sinks and kitchens be widely separated would seem to be unnecessary, yet for many years they were, by regulation, located in close proximity — and even recent modifications leave the matter entirely to the discretion of the commanding officer and prescribe no minimum of space to be maintained between them. During the war with Spain, as a result of lack of official regulation in this respect, in certain volunteer regiments the sinks were reported as beiag only a few feet distant from the kitchens. A return to the old plan of encampment, ia which the latriaes and kitchens were on opposite sides of the camp area and separated by a distance of 200 yards or more, is evidently highly desirable. If the camp be for a single night only, a latrine trench of a depth of two feet wiU be sufficient; but where a stay of several days is contem- plated the sinks must be made correspondingly deeper. For such camps a depth of about eight feet is usually considered as desirable; but under certain circumstances this depth cannot be attained. At Chickamauga a superficial rocky sub-stratum frequently prevented excavation to a depth of more than three or four feet ; while troops at Tampa awaiting embarka- tion for Santiago were encamped where the ground water was at an even less distance below the smiace. Under such conditions, it is evident that either the fsecal deposits are insufficiently covered with earth or the digging of new sinks must be an almost daily necessity. The employment of either alternative would largely conduce to the unhealthfulness of a command; since improperly covered ftecal matter emits foul odors and affords con- stant opportunity for the spread of infection by means of flies, while a large number of shallow sinks contract the healthful limits of a camp. The best remedy for such conditions consists, of course, in the abandonment of such an undesirable site. Should this plan conflict with military necessity then some other method for the disposal of excreta must be adopted. THE SANITAEY ADMINISTEATIOlSr OF THE CAMP. 383 The length, of the latrine trench depends upon the number of men which the sink is intended to accommodate. For a single company of one hundred men a length of twenty feet is sufficient, with a proportionate increase for each additional organisation. The width of the trench should be only of about two feet, since greater breadth is unnecessary and requires the use of more earth to cover the excreta. The soil removed from the sink should be piled to the rear, whence it can be scattered as needed over the deposits. The seat is formed by a stout pole, preferably one from which the bark has been removed, laid horizontally at a proper height over forked uprights. A back-rest may be formed by a similar pole, but this is often omitted. The latrine should be surrounded by a screen of brush, leafy boughs, old canvas, gunny-sacks or other available material; admit- tance being afforded by a valvular opening. In the British service, strips of canvas are supplied for this purpose. WTiere the camp is to be occupied for a night only, the latrine may be left unsheltered ; but where a somewhat •<™^y^ Fig. 165.— Construction of Latrine lor Temporary Camps. longer occupancy is anticipated some protection from the elements is ad- visable — and for this ptirpose the issue of canvas or boards should be authorized. In hot seasons or climates, the sink is advantageously covered with a roof of boughs to keep off the sun. This shelter rapidly dries, and on the abandonment of the camp it should be destroyed by fire. Wherever a camp site is to be occupied more than two or three days, the latrine trench should be boxed in and converted into a closed vault, flies being thus excluded. The holes should have hinged covers, and these should be prevented from being raised to quite a right angle by a horizontal paral- lel bar running above the seat. This renders the lids self-closing, and at the same time prevents squatting on the seats. To avoid the soiling of the latter, a separate place for urination should be provided ; a sloping trough of metal or tarred wood answering for this purpose. Access to the pit for the pur- pose of covering the dejecta should be had at the rear by a trap door, ' opening outward. Such a latrine should be both ditched and sheltered to prevent the vault from being flooded during wet weather. Under such circumstances a raia-tight box or bin for the storage of lime should be provided, while the seats should be scrubbed daily with soapsuds and a strong solution of carbolic acid or tricresol. 384 THEORY AND PRACTICE OF MILITARY HYGIENE. The care of the latrines is a most important factor in the preservation of the health of the command. The usual recommendations in this respect simply contemplate the coveritig of the dejecta with loose earth once ia twenty-four hours, usually at night. This attention is not sufficient ex- cept in rare instances, under favorable conditions of climate, season and son and where but relatively few men are using the siuk, and much greater and more constant care should be required — even iu the nightly camps while on the march. As a general rule, the old Mosaic ' law re- quiriug each individual to cover his own faecal discharges should be en- forced. The chief objection to the covering of his excreta by the individ- ual soldier is that of the more rapid filling up of sinks and the necessity for the excavation of new ones. This, however, is the argument of the company officer rather than the sanitary inspector, and labor thus econo- mized is largely at the expense of the health and comfort of the command. Care should be taken that unnecessarily large quantities of earth are not employed in covering the dejecta and that the amoimt used is properly distributed. In camps of anything but a transient nature, it should be the duty of some specially detailed soldier to visit the sink one hour after each meal and ensure that the dejecta are fully covered ; reporting its condition after each visit to the responsible officer. In addition, the condition of the latrine should be personally verified by a commissioned officer at least once during each twenty-four hours. When the trench is filled within two or three feet of the surface its use should be discontinued, and earth thrown in and well raised to mark the site. Sinks should always be fiUed in immediately prior to the resumption of the march. The care of latrines has, in the past, devolved upon the soldiers them- selves. The repugnance and opposition to the performance of such duty manifested by volunteer troops, however, together with the inefficient man- ner in which the sanitary police has been carried out by them, elicited a general order, in 1899, charging the Quartermaster's Department with the duty of policing the camps established for the muster out or organization of such volunteer forces. This duty includes the construction of latrines and the disposal of their contents, as well as of all garbage and waste ; and for this purpose the purchase of the necessary apparatus and the hiring of civilian labor was authorized. The practical results of this experiment have been very successful, and with raw troops this plan will probably be continued in the future. In the construction and location of the sinks, due care should be taken so to arrange the screens as to prevent the wind from blowing soiled scraps of toilet paper from the trench, and thus distributing possibly infectious material during their course through the camp, perhaps ultimately to gain entrance into a water supply. Should such paper have been scattered, it is to be promptly collected and destroyed. The fragments may be picked up on a poixited stick, placed in a gunny-sack and the latter bm-ned with its contents at the end of policing. It is well in this connection to emphasize the desirability of issuing a reasonable quantity of toilet paper as part of the allowance of the soldier, since the use of such material is largely con- ducive to both comfort and cleanliness. The employment of objects like sticks, grass or leaves may induce or aggravate irritation of the rectum or anus ; while, with the lack of washing facilities in camps, their use could THE SANITARY ADMINISTEATION OF THE CAMP. 385 scarcely fail to render the person and hands possible agents for the dis- semination of disease, through the subsecLuent handling of utensils used ia common, clothing and other articles. With a moving command the disinfection of the latrines is usually unnecessary. In the German army, which never bivouacs two consecu- tive days on the same spot, no disinfection of sinks is practiced. In camps of a more permanent character, during the occurrence of infectious disease, the disinfection of the sinks should be daily carried out — and un- der such circumstances it is particularly indicated during warm weather, when the danger of dissemination of infectious material by flies is con- stantly present. If milk of lime is used for this pm-pose, it is well not to be content with liming the dejecta but to pour a thick whitewash over the walls of the trench, so as to leave no resting-place for flies. In the absence of any chemical disinfectant, the bottom of the sink may be loosely covered with dry straw, hay, leaves or other inflammable material, and » — 2o:/iy ■ T 1 1 ^ 1^ s /^'^' i 1 J i & 2ST Fig. 166.— Ground Plan ol Trougli Latrine, Showing Seats and Urinal. this set on, fire. To facilitate this procedure, crude petroleum is sometimes sprinkled over the whole. The general methods for the disinfection of faecal matter are discussed elsewhere. The employment of excavated sinks fuRy meets the needs of moving commands, and furnishes, in fact, the most practicable method for the dis- position of dejecta during active campaign. If troops are to occupy a camp for but a few days, such sinks, slightly elaborated in detail, are still amply sufficient — but for camps of a semi-permanent character, particular- ly camps of mobilization and organization, latrine trenches should never be employed and other methods for the disposal of excreta are imperatively required. To meet this need, a plan for camp latrines has been devised by a board of medical officers — the system having proved itself as satisfactory in practice as it is excellent in theory. This arrangement prevents soil poUutipn by either urine or fseces, accomplishes their prompt disinfection and deodorization, and is at once cleanly, simple and convenient. It is not, however, applicable for winter use in cold climates. The system in- cludes the provision of a trough, urinal, latrine shed and excavating appa- ratus. Each latrine is intended to meet the needs of one hundred men; which number excrete about twenty-five pounds of faecal matter and forty gallons of urine during each twenty -four hours. One excavating apparatus is expected to be sufficient for the needs of each brigade. The trough, parabolic in cross-section, is of the following dimensions i 25 386 THEORY AND PEACTICE OP MILITARY HYGIENE. length, 14 feet; width at top, 22 inches; depth, 18 inches. It is made of sheets of galvanized iron, well riveted and smoothly soldered at joints and ends. The front and rear sides of the trough are given additional strength , by means of an iron rod one-fourth of an inch in diameter, over which the Fig. 167.— Perspectlye View of Latrine Trougli. Section of Lid Open. edges are turned. The general shape of the trough is such as to present a curved surface throughout; avoiding corners in which material could col- lect and thus ensuriag its easy emptying and cleansing. To better accom- plish the latter, one end of the trough is raised to a height of four inches above the level. This trough is supported by a framework consisting of four pieces so cut as accurately to fit its surface; the four frames being placed one at either end of the trough and the other two equally spaced. FiGf. 168.— Urinal in Trough Latrine. These frames are joined at the rear of the trough by two pieces 1 by 3 inches, one of these at the bottom and the other at the top of the frame. In front, the trough is completely boarded in by 1-inch material. The lid consists of two sections, each 7 feet long and containing three and one- half openings, or seven openings in aU. It is made of 1-inch material; the THE SANITAEY ADMIMISTEATION OF THE CAMP. 387 several pieces being held together, in front and rear, by a batten 1 by 1^ inches wide. Each section of the lid is provided with three hinges at the r^ar. The ends of the trough are boxed in and give support to a board 1 by 12 inches, rising to a height of 23-| inches in front and above the lid; the upper edge of this board being cut sloping to the extent of three inches. These end boards give support to another board, 14 feet 4 inches long by 12 inches wide, which is intend- ed to prevent men from standing on the Kd. This board should also be braced from the roof of the latrine shed. It is thus seen that the trough is enclosed by a complete framework, which is intended to secure sup- port whUe in use and safety during transportation, should the latter become necessary. When placed in position, the height of the upper end of the trough above the floor, including lid, should be 20-^ inches; at the lower end 16 inches. This necessitates an opening, in the floor of the latrine, corresponding to the width and length of the framework of the trough. The rear margin of this opening should be at least 4 inches from the studding of the rear wall of the buildiag, so as to permit the raising of each section of the lid. The lid of the trough is divided into seven spaces, each 1 foot 11 J inches in breadth by 1 foot 10 inches in depth ; the sides of the spaces being indicated by a vertical board 4 inches in height and beveled at each end. Each space is provided with an open- ing, so shaped as to prevent, as much as possible, the soiling of its edges by faecal matter. This opening, 4 by 3 inches in front, expands to a width of 8 «by 8 inches, this part having its edges well beveled, and is Fig. 169.— Cross-SecHou of Urinal. Fig. 170.— Perspective View of Trough Latrine Shed. then extended backward to the rear of the trough and cut away as much as possible without weakening too much the strength of the lid. In other words, both the front and the rear of the ordinary watercloset seat is large- ly cut away. This is intended to avoid both wetting the front of the seat with urine and its rear edges with precipitate diarrhoeal discharges. 388 THEORY AND PEACTICE OF MILITARY HYGIENE. The urinal consists of a galvanized iron trough fastened to the end and rear walls of the latrine, at a height of 2 feet 6 inches from the floor. It measures 9 feet 7 inches in length by 8 inches in width, and has a depth of 4 inches. Its rear side is extended 18 inches upwards, so as to protect the wall of the latrine from any possible contamination with urine. It has a fall of five inches, and empties into the upper end of the large trough by means of a pipe two inches in diameter. When ready for use, water should be poured into the larger trough until it has a depth of at least two inches at the upper end. To this is then added one-sixth of a barrel of lime and the two are well mixed with a wooden paddle. Lime should, also, be freely sprinkled in the urinal. The latrine shelter consists of a frame building 8 by 20 feet, inside measurements. The height of the roof at the rear is 6 feet 6 inches. The front wall of the buildioig is prolonged 2 feet at either end, and is provided with a projecting hood throughout its entire length. This hood protects an openiag 20 feet in length by 12 inches in width, intended for ven- tilation and lighting; and which, in warm climates, should be extended along the sides and rear of the building so as to insure a bet- ter circulation of air within the closet. The lengthen- ing of the front wall allows for a protected entrance, 2 feet in width, at each end of the building, for persons and also for barrels containing disinfectants. A door 3 feet 6 inches by 2 feet 6 inches is provided at the end of the closet, opposite that of the urinal, through which suction hose can be introduced for the removal of the con- tents of the trough. Through this door the trough, enclosed in its frame, can be removed whenever such action becomes necessary. The closet is properly floored and should be lighted at night by a suitable reflecting lan- tern. The excavating apparatus of this latrine system consists of a strongly constructed wagon-bed, mounted on broad-tired wheels, supporting a water- tight tank having a capacity of 500 gallons. A 6-inch opening at the rear end of the tank, controlled by the turning of a lever, serves for the purpose of emptying the contents. Accompanying this wagon is a pumping appa- ratus, consisting of a cylinder capable of withstanding high pressure, two 20-foot lengths of 3-iach rubber hose, with two pahs of brass couplings and a removable handle for working the pump. The latter is single acting and in form a straight cylinder provided with one fixed valve (the induction), and one movable — the latter attached to the piston and moving in the center of the cylinder; the openings of both valves being in a Fig. 171.- -Odorless Excavating Tank Wagon, witli Detachable Pump. THE SANITAEY ADMINISTRATION OP THE CAMP. 389 direct line. THe passage of material through the pump is therefore direct and without counter currents ; and such is its capacity for passing obstruc- tions that sticks, stones, shavings, rags or other obstructions, even if of the size of a pair of heavy cloth trousers or a full-size army blanket, are pumped through with ease. In fact, any object not too large to enter the suction hose will pass freely through the valves without interfering with their action. This pump is provided with side bars for lifting purposes, and is sup- ported on a pair of strong iron wheels. When in use, it is connected at each end of its cylinder with one of the ends of the 3-inch hose. One free end of the hose is then connected with the pipe on top of the tank, and the free end of the other length of hose placed in the trough to be emp- tied. The pump is rapidly worked by one or two men and the contents of the trough are quickly pumped into the tank, a gallon or more of water being placed in the cylinder of the pump before the connections are made. Fig. 172.— The Can Latrine System, as Used In the Camp at Lexington, Kentucky. As soon as the trough has been emptied, the end of the hose is elevated and securely closed with one of the couplings provided for that purpose. This length of hose is now disconnected, its end closed with the coupling and the end of the pump also tightly closed by a valve provided for that purpose. The same steps are taken in detaching the other length of hose from the tank, and in this way none of the contents of the pump or hose are spilled on the ground. The two lengths of hose are placed in position along the sides of the tank, the pump is hitched to the rear axle of the wagon by the attachment provided, and the excavator wagon driven to the next trough which is to receive attention. If the command is removed to another camp the pump may be drawn at the rear of the wagon. Three men are required to handle each excavating apparatus. Various other systems for the disposal of the excreta have also been employed in our standing military camps, the types varying with the in- genuity of the designer and the material and facilities at hand. These arrangements were many of them modifications of the bucket system, as shown in the accompanying illustration of a latrine in use in the camp at Lexington, Ky. This system as a whole, when properly supervised, gave 390 THEORY AND PRACTICE OE MILITARY HYGIENE. fairly good results — but was quite inferior to the trough system, already described. The receptacles were difficult to disinfect or keep clean, and by their careless handling the pollution of the soil in the vicinity of the latrine was very liable to occur. The system possessed, however, the great military merit of being readily improvised and of not requiring the provis- ion of elaborate special apparatus. It is used to a considerable extent in the French army, and is also employed under certain conditions in the British service. A removable galvanized iron tub has been recommended for use in re- ceiving the discharges of the sick in field hospitals. This tub has a dia- meter and depth of 19 inches. It is provided with a wooden seat and Hd, capable of being securely fastened by brass clamps, so as to prevent spilling of the contents during removal to the disinfecting station; a second lid is perforated with a pipe for the entrance of steam or boiling water and also a discharge pipe for the escape of the contents. When in use, this tub should contain several gallons of milk of lime. From a sanitary standpoint the disposal of faecal matter, under any conditions, is best accomplished by cremation. Bearing this fact in mind, a number of attempts have been made to perfect apparatus for the de- struction of excrement by fire, of such construction as to render prac- ticable their use by troops in the field. Of these, perhaps the most satisfactory is the Bissell Incinerator, which has recently been given a careful trial in the camps of instruc- tion of the New York National Guard. Reports made upon this ap- paratus show that it is capable of efficiently cremating its contents, with- out the production of any very offensive odor, within the space of an hour. Garbage may also be incinerated, the length of time depending upon the nature of the material to be destroyed and the amount of moist- ure present. The details of construction and method of operation are simple and are plainly shown in the accompanying illustration, the let- ter A marking the upper space between the pot or receptacle B and the top of the casing ; C is the fire-box and D is the draft passage ; E is a passage leading down from an upper space A into the draft passage D, and F is an opening leading from the fire-box up into the same passage D. A deflecting wall G is located midway between the passage E and opening F. The odors from the material in the pot or receptacle are drawn down through the passage E by the draft, as indicated by the arrows, and then pass through the passage D into the chinmey or smoke pipe H, and the products of combustion from the fire-pot C pass up through the opening F into the same passage; mingling therein with the odors and gases from the upper space A, which are destroyed before passing into the pipe H. riG. 173.— Bissell Incinerator, in Vertical Sec- tion. THE SANITAEY ADMINISTKATION OF THE CAMP. 391 The apparatus, as made for military use, has a capacity of 5 gallons and a weight of 115 pounds. When the iuciuerator is fuU, the wooden seat is removed and replaced by an iron cover. Fire is made in the fire-box, wood generally being used, and the back of the draft near the chimney-pipe is opened. It is stated that the currents of air passing through the appara- tus during accumulation of the faecal matter are sufficient to carry off all odors through the smoke pipe. For camps of instruction or mobilization this apparatus appears to have given satisfaction, and it may serve a useful purpose under the conditions in which the trough latrine system or the Smith crematory — Plater dis- cussed — ^would be successfully employed. Eecently, however, the effort has been made to render this apparatus so transportable as to enable it to accompany marching troops, and special latrine wagons are now in use in the New York National Guard, each wagon containing eight individual Fig. 174.— Blssell Incinerator Wagon for Excrement and Garbage, as Used in the National Guard, State ol New York. incinerators with fuel boxes. These latrine wagons are large and cumber- some, and weigh, complete, 4,000 pounds each. There are many practical objections to the use of such wagons in the military service. They are intended especially for marching troops, but simple excavated latrines are in all respects excellent under just such circumstances. The allowance of latrine seats in one of these wagons, if it were assigned to a company of 100 men, would only be eight per cent. ; yet even with this scanty allow- ance there would be required, for the needs of a division of 10,000 men, no less than 100 latrine wagons. Such an addition to the train would seriously impair the mobility of a military force, and the wagons being heavy, they would require some 400 animals for their transportation. Further, it is obvious that they could not closely accompany a marching column, but would have to form a part of the general wagon train ; and thus they would not reach the camping ground until some time after the arrival of the troops, by whom, in the absence of latrine facilities, the locality 392 THEOEY AND PEACTICE OF MILITAEY HYGIENE. would inevitably have been more or less contaminated. This latrine wagon is an excellent example of the many devices proposed for army use, which, though they may be excellent in theory, are totally impracticable under the actual conditions existing in the military service. The important part played by urine in the spread of infectious disease, more especially typhoid fever, has until recently been practically unrecog- nized in the military service, and hence the me thods for its disposition in camps have been largely neglected. With the discovery, in 1898, that enormous numbers of the specific micro-organisms are often present in the urinary excretions of typhoid fever patients, the disposal of the urine in any but the encampments of marching troops assumes new significance and importance to the military sanitarian. With respect to the destructive epidemics of typhoid fever occurring in the home camps during the Spanish- American war, the medical board engaged in their investigation considered Fie. 175.— Sectional View of Interior ol Bissell Incinerator Wagon. the pollution of the camp site by infected urine as one of the most potent factors in their causation. Satisfactory arrangements can with difficulty be made in camps to pre- vent soil contamination by urine ; not only on account of the facility with which the operation is accomplished and the comparatively slight danger of its detection, but also because of the idea which has always prevailed as to the harmlessness of such action. Faecal matter is repulsive to both sight and smeU, while urine, passed upon the ground, is neither; and the soldier who fails to resort to the sink or urine tub rarely leaves traces behind him unless there has been a recent snowfall. Each delinquent, if he considers the matter at aU, imagines himself to be the only one committing a sanitary fault of this character, and relieves his conscience by the thought that such an individual act can have no effect upon the general welfare; failing en- tirely to appreciate the fact that his comrades are probably looking at the matter from identically the same standpoint. If the weather be good, the sinks receive the greater portion of the urine voided during the day. In bad weather, some comparatively sheltered spot, usually between tents or huts, is often selected for urination; while at night aU parts of the company area are liable to pollution. Indis- criminate contamination of the camp site of this character is a marked THE SANITARY ADMINISTRATION OF THE CAMP. 393 characteristic of raw or ill-disciplined troops. It should be specifically prohibited in orders ; the infraction of which should be followed by severe punishment. To limit contamiaation of the camp area, it is sometimes well, with raw troops, to designate certain places, nearer than the sinks, for the reception of urine — and in all fixed camps, urinals should be established near the canteen and mess shelters. Night-tubs for the reception of urine are essential in a standing camp; although if convenient for aU they are liable to be too near to some. For this purpose, charred or tarred tubs or hali barrels — or better yet, barrel-shaped galvanized iron receptacles — should be employed. These should be placed in the center of the company streets at retreat and be removed at reveille ; being emptied, disinfected and exposed to the sun during the day. While in use, they should always contain a sufficient amount of some disinfectant solution, preferably milk of lime. The location of the urine tub as well as the latrine should be marked at night by lanterns to prevent accidental soU pollution, and with semi-permanent camps the locality in which the night tub is placed can advantageously be cemented. In general, with regard to the observance of sanitary rules as to the disposition of excreta, untrained troops are difficult to control and it is almost useless to appeal to their intelligence. Concerning the outbreak of typhoid fever among the volunteer troops at Camp Alger, Va., in 1898, it was re- ported as follows : " By the careless and filthy habits of the men the woods surrounding the camp became generally the receptacles of faecal matter. Sentinels who were placed to prevent this use of the surroundings of the camp failed to report their comxades ; and I do not believe that in a single instance an arrest took place for this cause, which was one of the principal ones of the infection of the camp." With such undisciplined troops, it is evidently necessary that the latrine should be so comfortable and conven- ient that it will be preferred by the soldier to any other point for the dis- position of his excreta. In this connection, it should not be forgotten that savages, although their habits may be highly unsanitary, remove their habitations from time to time as their surroundings and camp areas become filthy and polluted. Eaw troops Kving like savages in their disregard of sanitary principles, without moving camp as often as do these savages, cannot fail to be scourged by epidemic disease as a result of their ignor- ance and neglect. Garbage and Refuse. — Kitchen garbage should always be kept sep- arate from dry rubbish. It should never be thrown upon the ground, and should not be buried within the limits of the regimental area imless the camp is positively known to be of a transient character. Kitchen refuse usually contains about eighty per cent, of moisture, and if present in large quantity its destruction by the kitchen fire alone is scarcely practi- cable. There is, in addition, a large amount of greasy water which re- quires disposition, and this, like garbage, should never be thrown upon the camping ground to attract flies and contaminate the soil. In standing camps, all kitchen waste should be placed in tight receptacles ; for warm weather or climates these are preferably made of galvanized iron, provided with lids and capable of being both readily opened and snugly closed. Such receptacles should be placed on raised platforms for the better pro- tection of themselves and the groimd beneath them, and should be emptied 394 THEORY AND PRACTICE OP MILITARY HYGIENE. at least once daily. Before being returned to use they should be washed and disinfected. Under no circumstances, in such camps, should the garbage be buried ; and least of all, to reduce 'its bulk, should it be dried by being thrown on the ground — as was done in certain volunteer organi- zations in the late war. Besides the resulting soil pollution, such action greatly increases the number of flies, which, despite aU efforts, infest a summer camp of any permanency. The proportion of fluid in ordinary refuse from the camp kitchen is usually considerable ; and with small improvised crematories this is a prac- tical difiiculty in the way of the destruction of garbage by fire. Under such circumstances the separation of the solids from the fluid portion be- comes desirable. This can readily be done by pouring it over a strainer of any kind. The Conley garbage receptacle is an excellent arrangement for this purpose. It consists merely of two galvanized iron cylindrical con- tainers of the same diameter, each of about one-half barrel capacity. In one of the containers the bottom is replaced by a heavy wire mesh, and this fits into the top of the second container. The upper receptacle is Fig. 176.— Sanitary Garbage and Refuse Cart, Used in the United States Army. closed at the top with a lid. The solids of the garbage are separated out and are retained in the upper container in a condition suitable for crema- tion. The fluids run through into the lower can and are then readily re- moved for suitable disposition. These two containers can be firmly locked together to facilitate handling. Carts or wagons for the removal of garbage to the place of disposition should be made in special designs adapted to their particular purpose, and the collection of garbage and refuse with the aid of the leaky and offen- sive wooden barrels of an open wagon can have no place in the proper sanitary policing of the military encampment. A somewhat popular method of disposal of garbage in large camps has been its presentation or sale by company cooks to irresponsible civilians, who collect and cart it through the camp, without regard to sanitation, in vehicles and receptacles not at all suited to the work in which they are employed. Such a dis- position of kitchen refuse should never be permitted. The general health demands that its removal shall be accomplished in vehicles which do not absorb moisture, are water tight and as nearly as possible air tight, are easily cleansed and readily loaded and discharged of their contents. Such carts, in the proportion of one to each brigade, should be' issued for use THE SANITAEY ADMINISTEATION OP THE CAMP. 395 with troops ia the field under all conditions except those of actual cam- paign. In large camps of mobilization or organization, and particularly where troops have gone into permanent camp or winter quarters, the em- ployment of such special means of conveyance is imperative in the limita- tion of soil pollution. A cart of this character has for several years been in use in various garrisons throughout the United States and should not be permitted to find its only field of applicability in the routine of a well- ordered military post. It is built of sheet iron, is water-tight, and is provided with closely fitting lids having wide flanges and capable of beiag locked ta position. The axle is encased in a steel tube which passes through the body of the vehicle. The weight of the cart is 1,500 pounds and its capacity 54 cubic feet. The body is well balanced, and is adjust- able at any angle for the discharge of the contents and con- venience in cleansing. A place for the final disposition of refuse should be set aside upon the establishment of the camp. This should be at a con- siderable distance ; varying, however, with the climate, season, size of the command and amount of available transportation. It should always be outside of the camp area, placed to leeward of prevailing wiads and so located as to avoid possible pollution of the water supply. Even upon this spot, kitchen waste and other organic refuse should never be thrown upon the surface of the ground or dumped in ravines and gullies. Such accumulations of filth, in the presence of heat and moist- ure, rapidly undergo fermen- tation and decay. They form favorable culture media for pathogenic bacteria, and from their general composition the presence of those causing the commoner infectious diseases may safely be presumed. In standing camps, cre- mation is the only proper method for the destruction of garbage. Stable manitte, after the daily collection, should be carted to the general dumping-ground and there burned ; as should also all slaughter- house offal and dead animals. AU such refuse as straw, empty tias, rags or bones should be subjected to the action of fire ; any incombustible res- idue being buried. In the field, the methods for the cremation of refuse vary from the use of the fire of the company kitchen to the employment of specially con- structed crematories. An effective means for the destruction of garbage, much used in several of the large camps and in the municipal sanitation of Santiago while under military control, consists in its incorporation with more combustible material, such as straw or manure, and the saturation of the whole with crude petroleum before ignition. In one mihtary camp, during the late war, a number of old steel rails were so disposed as to form <3S - Fig. 177.— Improvised Crematory Used at Camp Columbia, near Havana. 396 THEORY AND PEACTICE OF MILITARY HYGIENE. a platform, under which a brisk fire was maiataiaed. The garbage was thrown on this platform and was said to have been promptly and efficiently destroyed. In the Crimean War, the English bm-ned their camp offal in improvised incinerators made much in the fashion of lime kilns ; and a similar method was in use ia the camp of the 1st Army Corps at Lexiag- ton, Ky. In the camp of the 7th Army Corps, at Havana, several crema- tories constructed from old boilers were ia use and were said to have excel- lently accomplished their pm-pose. They were, however, liable to become clogged by an iacombustible residue imless given careful attention. Among the more elaborate forms of apparatus for the combustion of garbage and camp refuse, the Conley field crematory is excellent. This crematory is made up of but few parts, and these can be readily separated from each other and packed so as to occupy but small space. The mate- FiG. 178.— Conley Camp Crematory. rials employed ia its construction are sheet iron and asbestos. The side walls of the apparatus are each made of four plates, having flanges which enable them to be fastened together with stove bolts. The front and rear walls are attached to the sides in a similar manner. The top plate of the crematory compri'ses fom separable sections which are curved transversely, the outer edges haviag upturned flanges, and when these plates are con- nected they are adapted to fit within the side and end walls, resting upon projections attached to the upper plates of the side walls. The two rear plates used in making up the top have openings, above which and near the center are placed hoppers. The other plates have openings over which are placed chimneys, which are established adjacent to the corners near the front wall. No bottom plates are required, and the side walls rest directly upon the ground. Within the furnace is a longitudinal dividing wall of sheet iron, possessing recesses in which rest the inner journals of the upper grate bars. These are concave in cross section, so that when their con- cave portions are upward they form a series of pans in which the Kquid THE SANITAEY ADMINISTRATION OF THE CAMP. 397 Fig. 179.— Transverse Section of Conley Camp Crematory. portion of the garbage is evaporated. Some distance from the front wall of the fm'nace, and attached to the longitudinal dividing wall, is a vertical plate which forms the rear wall of the ash-pit and serves as a support for the rear ends of grate-bars of ordinary pattern, which are supported anteri- orly by the front wall. Running from the upper side of the vertical plate, so as to extend from the rear of the ash-pit and incline upward there- from, is a corrugated iron plate, to the rear end of which is bolted a small curved sheet of metal extend- ing to the rear waU. The vertical waUs below the grates, and above the grate-bars and the corrugated plate, are covered with asbestos, so as to protect the side plates from direct contact with the flame — and the longitudinal wall is similarly protected. The object of corrugating the plate transversely is to form a series of recesses which will retain a certain amount of the fluids which may fall from the upper grates, and such fluids and ashes serve to protect the plate from direct con- tact with the flames. For evaporation of the fluid portion of the garbage, receptacles are bolted to the sides of the fm'nace above the evaporating grates, and these are provided with valved conduits which lead into the furnace above the evaporating grates. These receptacles are also provided with small pipes leading into the furnace to allow of the escape of the steam generated. For camp use the liquid and solid parts of the garbage should be separated ; the solid parts being passed into the furnace through the doors above the grate-bars and also through the hoppers. Wood or other fuel is placed upon the lower grates, and when the fire is started the products of com- bustion wOl pass under and over the garbage, as indicated by the arrows in Fig. 180, and when the same is sufficiently dried one or more of the grates may be dumped, so that the dried garbage wiU serve as fuel for burning subsequent charges. As the garbage is heated, the grease and other like ma- terial is caught in the concave grate-bars and the liqidd is evaporated; so that the concave grates not only serve as a series of evaporating-pans, but the liquid which they may contain wiQ prevent the burning out of the grates. The fluids which have been separated from the garbage may be placed in the receptacles and fed into the furnace over the concave grates by the pipes provided. Each of the grates is provided with means for dumping, one independent Fig. 180.— Longitudinal Section of Conley Camp Crematory. 398 THEORY AND PEACTICE OF MILITARY HYGIENE. of the other, so that the required amount of dried and heated garbage may be dumped either upon the deflecting-plate or upon the grate. The metal plates constituting the sides, ends, top, and division-wall are completely covered on their inner sides with sheets of asbestos, which have an interposed wire netting or fabric; such sheets of fire-proof material being attacl^ed to the plates by staples. With this furnace a comparatively small amount of wood or fuel is needed to dry out the first charge of garbage, and after the fire is started the garbage which is dried out serves as fuel for subsequent deposits. When the garbage in one of the grates has been dried, this grate can be dumped; and while maintained in a vertical position the products of com- bustion will pass around it between the grates adjacent. Thus should it at any time be desired to use only a few of the grates, those that are not required may be placed in a vertical position, so that the products of com- bustion will pass entirely around those in use. By duplicating the construction on each side of the center of the fur- nace the garbage may be fed into the same ; so that what is deposited on one set of concave grate-bars or receptacles, after having been dried out, may be dumped on the grates beneath and used as fuel for a subsequent charge. The products of combustion from the garbage on one of the sets of grates, as it is being consumed, will heat and dry out the garbage on the other set of concave grates, and by feeding the garbage alternately through the different hoppers it is used as fuel. This crematory has been given a practical trial in the military service, and has proved to be an effective way of disposing of large quantities of garbage and camp offal. It can be set up by two men in four or five hours, and can be taken apart for transportation in much less time. One crematory will destroy the solid garbage for a brigade, and will evaporate fluids at the rate of 25 gallons per hour. Complete, its weight is only 900 to 1,000 pounds. But little fuel is required for its operation; and for the combustion of camp refuse, outside of excrement, it appears to be in all respects very satisfactory. A slightly modified form of this crematory, 6 feet long, 3 feet wide and 33 inches high, has been mounted on trucks for convenience in consimiing the garbage of a large camp. This is intended to collect the refuse from various stations and burn it on the spot or while in transit. It is capable of binning all the solid refuse for a brigade, but its evaporating power is somewhat less than that of the fixed apparatus. Its weight, without the trucks, is about 1,000 pounds. This crematory wagon is constructed with double walls around the furnace and also has a flooring of clay to diminish the loss of heat. An ash-pit is attached to the fmnace just- behind the rear axle. The smoke-stacks are hinged, so that they may be lowered to the top of the furnace during transportation. The Smith portable crematory, of which a considerable niunber have been purchased for use at tropical stations, has a wider field of usefulness than the above, since it is designed to serve the combined purposes of a latrine and refuse crematory. The apparatus consists of a series of hoppers arranged in a circle about a central furnace. The mine and faecal matter are received upon flat excreta plates, so inclined that the fluid parts flow toward the central fire-box and are subjected to constant drying. The THE SANITARY ADMINISTRATION OF THE CAMP. 399 Fir. 181.— General Plan ol the Smith Camp Crematory, The excreta hoppers are cut away In front to better show the detail. solid part of the excreta is from time to time pushed from beneath the hoppers to a space around the fire-pot, and when dried, can at any time be raked on the grate and burned. A large evaporating pan is placed above the fire for the reception of fluid and solid garbage. When dried suffi- ciently, the garbage pan is revolved by a crank and the contents are deposited on the grate, where it serves as fuel. As the garbage falls upon a grate above the fire, and not directly upon the fuel, there is no need of complete drying in the evaporator if extra heavy duty is required. An advantage possessed by this appa- ratus is the possibility of applying the flame immediately beneath the excreta plates, in order, if necessary, to hasten the drying and sterilization of the excreta as well as the adjacent parts of the appa- ratus. The whole plant may be sterilised at baking temperature if the draft is shut off at the seats. The fact that, owing to its peculiar construction, the central fire, while drying out the excreta and garbage, does not increase the temperature of the closet must be considered as another ad- vantage, especially in hot climates. In operation, the apparatus is odorless. The ventilation is excellent, the downward draft through the hopper seats being sufficiently strong to prevent the egress of flies. This venti- lation is secured by means of a pipe three feet in diameter, rising to a height of forty or more feet. The crematory is economical in action and capable of using as fuel almost any combustible material, such as wood, under- brush, straw, manure or soft coal, and the full capacity of uriae, excreta and wet garbage can be desiccated and burned in the short space of three hours. This apparatus is transportable in the sense that it consists of a num- ber of pieces of cast iron, joined together by bolts, which can be taken apart by ten men in five or six hours and re-erected in about the same time. The weight of an apparatus suitable for the needs of a company is, however, about 5,200 pounds, while a crematory sufficient for the needs of two compa- \\:iiIVnv>^' nies would weigh about i\i^« 7,000 pounds. The por- FIG. 183.— Plan of SmltH Camp Crematory above Closet Hoppers. tablllty IS therefore Only 400 THEOEY AND PRACTICE OF MILITAEY HYGIENE. such as would permit of its erection in more or less permanent camps, in which, after all, the need for such a crematory alone exists. This cre- matory, after exhaustive trials in the United States and Cuba, was strongly recommended by the several boards appointed to pass upon its merits, and appears satisfactorily to fulfill every purpose for which a camp crematory can be required. Whatever be the methods employed for the reception, gathering and disposal of garbage and refuse, they should be under the direct super- vision and control of a medical officer. Camp Police. ^ — The term police, in the military service, implies the maintenance of cleanliness rather than of order, and for its proper execution the commanding of&cer is re- sponsible. Company officers are required to maintain neatness and proper sanitary conditions within their respective organiza- tions, and the police of the company area devolves upon the men of that command. In the regimental camp the work of general policing comes imder the jurisdiction of the officer of the day, who has control of the prisoners and guard and is responsible to the commanding officer for the order and cleanliness of the camp. The general work of policing is performed by prisoners; but if these are insufficient, fatigue details are made from the command. With inexperienced troops, or with an incapa- ble administration, the maintenance of proper police is rare; and under the former circumstances the more distasteful duties of camp police may advantageously be performed by civilians. The general police detail cleans up the regimental area, attends to the sinks and the disposal of refuse, and performs any other duties which may be necessary for the sanitation of the camp and the comfort of the men. To ensure the proper performance of this policing, inspections are required by regulations ; monthly on the part the commanding officer and both daily and weekly by the company com- mander. The daily inspections are largely concerned with the sanitation and interior economy of the company — the weekly inspection being more in the nature of a military formality. This system ensures that any con- ditions unfavorably affecting the health or comfort of the command are promptly known to those individuals by whom then- remedy can be ac- complished. The maintenance of cleanliness of the camp requires syste- matic and constant watchfulness on the part of officers — and special regula- tions as to police, suited to existing conditions, can with advantage be pro- mulgated from time to time. Company streets should be swept daily, and the intervening spaces be- tween huts or tents should be carefully policed. AU refuse should be at Fig. 183.- -Horlzontal Section of Smltli Camp Crematory above tte Excreta Plates. THE SAJ^ITAEY ADMINISTKATION OE THE CAMP. 401 once removed, and nothing left behind to serve as a starting-point for fur- ther accumulation. The interior of habitations should be maintained in a state of scrupulous cleanliness, and should be swept or brushed out daily. Serviceable brooms for camp use can be made by tying together a number of small twigs of equal length — or the leafy branches of trees may be made to answer a similar purpose. If improvised bedsteads have been con- structed, articles should not be allowed to collect under them; while if huts are occupied as quarters, special attention to the cleanliness of beams, shelves and other out-of-the-way places is required. All arms, blankets, and bedding should be daily exposed to the sunlight to prevent dampness, and the floor of the habitation should be cleared. Poles supported by forked uprights may be put up in suitable places, and are convenient for the drying and sunning of garments and bedding. In camp, as well as in barracks, neatness and order are of great impor- tance and their maintenance should be required. A want of care about the disposition of the equipment of the soldier would seem at first sight to be a military matter ; but from a sanitary point of view it indicates a lax- ity as to detail which, if not corrected, will often result in carelessness as to cleanliness of the person and surroundings. An accumulation of organic matter imder the floors of tents or huts is a certain result of the absence of an efficient police ; while if dirt floors are used, every care is necessary to limit their contamination to the minimum by the maintenance of cleanliness. In any but transient camps, food should under no circumstances be brought into tents. Special shelters should be provided for use at meals — or otherwise the remnants of food are certain to be scattered about the tent area and its vicinity. Dogs, in any number, should never be allowed in camp. In general, no contamination of the air space should be permitted, save that which necessarily depends upon occupancy. Before the abandonment of an old camp, its site should be as thoroughly pohced as if its continued occupancy was contemplated. An imcleanly summer camp is soon subjected to a plague of flies, which, in addition to its direct effect in promoting disease, becomes a serious source of irritation and annoyance to the command. To protect against such an invasion, or to limit its effects, due care should be given to the dis- position of the excreta and refuse. As aheady stated, the latrine trenches should be enclosed and darkened and flies excluded; such an arrangement being insisted upon by the sanitary officer in any camp of comparative per- manency. It is short-sighted economy which takes into consideration the small additional expense involved; yet certain commanding officers and quartermasters wiU be foimd, for this reason, to oppose such a suggestion. Lime, freely used, repels insect life — as does also crude petroleum. The latter, well sprinkled over an open latrine trench, is most valuable in keep- ing flies away from its contents. The low cost of crude petroleum, sixty to seventy -five cents per barrel, renders its employment not at all expensive. The condition of the outskirts of the camp requires careful attention, and the removal of refuse from the camp area only to deposit it on the surface ui the vicinity should never be permitted. The purlieus of the encampment should be kept as free from noxious material as the camping ground itself. Cleanliness should not be considered as accomplished, if the camp present a neat appearance while at the same time hidden foci of pos- 26 402 THEOEY AND PRACTICE OF MILITARY HYGIENE. sible infection are permitted to exist. The sanitary index of the encamp- ment is not to be fomid in the best cared-for huts or tents, but' rather in those presenting conditions least desirable from such a standpoint. A single filthy habitation is a standing menace to the sanitary condition of the others. Soil contamination in camps is only a question of time, and the length of time a camp site can be safely occupied by troops depends largely upon the efficiency of its police. If proper cleanliness be not maintained, and dangerous refuse be not removed, the frequent transfer of the camp itself to a fi-esh site becomes imperative. It should be remembered that the use of disinfectants in camp is entirely subordinate to a frequent change of site and an efficient police. CHAPTER IX. POSTS, BAEEACKS, QUAETEES AND HOSPITALS. The general requirements for a healthful liabitation are thus summed up by Parkes : (1) A site dry and not malarious, and an aspect which gives light and cheerfulness. (2) A condition of house construction which ensures perfect dryness of foundation, waEs and roof. ( 3) A system of ventilation which carries off all respiratory impuri- ties. (4) A pure supply and proper removal of water, by means of which the proper cleanliness of all parts of the habitatioii can be ensured. (5) A system of immediate and perfect sewage removal, which renders it impossible that the air or water shall be contaminated from excreta. To this may be added : (6) An arrangement for the sufficient and equable distribution of heat. Location and Arrangement of Posts. — The same considerations of topography, soil, and exposure which have been discussed in connection with the location of camps, obviously _ apply with even greater force in the selection of sites for permanent posts and barracks. With camps, a bad site inadvertently chosen may be readily abandoned; but a post, once es- tablished in a locality of unhealthful character, is, from motives of econ- omy, given up with reluctance. In the past it has often happened in our service, where military stations were injudiciously located or planned, that this was due to the fact that the position taken" depended upon a chance combination of circumstances. Frequently the needs of the service re- quired a location, originally occupied for temporary purposes only, to be permanently garrisoned ; and thus from a camp or winter-quarters a mili- tary post was developed. Old buildings which had been hastily erected and roughly constructed for temporary shelter only, were usually retained in the permanent post to serve certain purposes and save labor. In many instances the post itself, thus brought into existence, was regarded as merely temporary, and no effort was made to drain, plan or beautify it. This method of developing a post has many obvious disadvantages ; and it is in general far preferable to let any rough work which may have been performed go for nothing, and start fresh on a carefully selected site, with a well-defined plan from the outset. In the future, under more settled military conditions, any such hap-hazard methods of development as have obtained in the past wiU scarcely be necessary — and in all instances the opinion of a sanitary officer should be obtained with reference to the location and arrangement of a proposed post before its construction. This has not always been done ia the past; and at many stations, ia the ■=B ] [ a c 404 THEORY AND PRACTICE OE MILITARY HYGIENE. establishment of which this precaution was omitted, the sick rate — as was to be expected — has been unduly high. In addition to the general requirements of a healthful site for habita- tions, as given elsewhere, the ground in the vicinity of barracks and quar- ters should usually be under-drained to a depth of six or eight feet. Statis- tics show that where the level of the ground water has been lowered, the health of the locality drained has been much improved. Buchanan found, in a large number of towns in England, that under-drainiag of the soQ was followed by a marked decrease ia the prevalence of tuberculosis. At Sal- isbury the mortality from this cause fell 39 per cent. ; at Eugby 33 per cent., and at Worthiag 36 per cent. The greater the number of draias, the better the result in retentive soils ; but in gravel and free soUs no more drains are required than will properly lower the ground water. As dry a site as possible should be selected ; bearing in mind that damp soils are always insalu- brious, and that it is a difficult and costly task to make an unwholesome place healthy. A safe rule to follow is to choose a site from which there is drain- age and into which there is no drainage; this applying to sub-soU as well as surface water. Usually such condi- tions can be satisfied in the im- ,„. ., . ™ . ^ _ „„■ ., . c^ , mediate vicinitv of a point Fig. 184.— Ground Plan of Fort Ellis, Montana, Showing ,.,..,.■', . Old Method ol Grouping the Buildings ol a Post. whlch it IS desired to gamSOn. Made-gi-ound should be avoided as sites for buildings unless the soil is known to be free from organic pollu- tion, in which case the site may be healthy. Posts should preferably be located away from the immediate vicinity of large cities. This usually gives more free space and purer air, while at the same time it limits the various temptations to vice which beset the soldier. In towns, density of population has a direct influence on the mortality of the inhabitants, and this rule appears to hold good also for the military service. Buildings should therefore not be crowded together; but on the other hand, too much ground in a post is undesirable, as it in- creases the difficulties of drainage and police. BuHdiiigs are properly lighted, aired, and sunned if no two are placed nearer to each other than twice the heiglit of the ridge of the taUer building. In their aspect, long barrack buildings, in temperate climates, should face the east to receive the full benefit of the sunshine, and give it access to both the long sides of the structure. It is desirable, also, that they be broadside to the prevailing wind ; and if built on a slope that they should be end-on to the side of the hiU. In their arrangement, no special dispo- sition is essential from a sanitary standpoint so long as the barracks do not interfere with each other in respect to the free sweep of the wind. In the British army the pavilion barracks are placed in paraRel lines. In our own service, posts were long constructed on the four sides of a POSTS, BARRACKS, QUARTERS AND HOSPITALS. 405 square, with a central parade — as is well shown in the accompanying plan of Fort Ellis. This quasi-defensive arrangement, a relic of the old stockaded posts necessary in the days of early Indian warfare, is no FORT ETHAN AJ.LEM, VERMOHT, 175 175 350 &25 I I I I I I I I I Fig. 185.— Post of Modem Construction, Showing Arrangement of Buildings. 1, Commanding officer's quarters ; 3, officers' quarters ; 3, guard-liouse ; 4, barracks : 5, band quarters ; 6, saddler stiops ; 7, hospital ; 8, non-commissioned staff quarters ; 9, cavalry drill-ball ; 10, cavalry stables ; 11, post ex- change ; 12, bakery ; 13, store-house ; 14, store-house ; 15, scale-house ; 16, forage-house ; 17, shops ; 18, ordnance; 19, fuel shed; 20, oil-house; 31, magazine; 32, water tower. longer required, and there is now no reason why a compulsory external form should govern internal arrangement. Posts built on this -plan are al- ways unsightly from the exterior, some of the buildings are necessarily badly oriented, and fuU advantage of the surface configuration of the 406 THEORY AND PRACTICE OF MILITARY HYGIENE. ground is not attained. In general, the arrangement of the buildiags, after reasonable convenience of administration is secured, should be varied in their relations according to the nature of the locality selected. This plan has been followed with advantage in the establishment of a number of posts of recent construction; among them being Forts Sheridan and Ethan AUen, plans of which are given in the accompanying illustrations. Fig. 186.— Plan ot Fort Sheridan, Illinois. 1, Officers' quarters ; 2, non-commissioned staff quarters ; 3, chapel ; 4, barracks ; 6, mess-hall ; 6, infantry drill-hall ; 7, fire station ; 8, post exchange ; 9, gun shed ; 10, Kuard house ; 11, ordnance store-house ; 13, bakery ; 13, storehouse ; 14, cold storage ; 15, shops ; 16, quartermaster's stable ; 17, wagon shed ; 18, stable guard house : 19, forage storehouse ; 30, cavalry stables ; 31, stable sergeant and saddler ; 33, cavalry guard house ; 23, cavalry drill-hall ; 24, magazine ; 25, bachelor officers' quarters and mesa. Arrangement and Plans of Barracks. — ^While military barracks appear to have been employed in Eome and Constantinople about the time of the Christian era, their use was shortly afterward discontinued. Dur- ing the Middle Ages the armies were comparatively smaU; and standing forces, as organized bodies, were not maintained. Where the shelter of soldiers became necessary, they were quartered on the civil population — much to the detriment of all concerned. During the feudal period, bands of armed retainers were sheltered by the nobles to whom they owed alle- giance and afforded protection, but no large bodies of troops were main- tained on a permanent footing. About two centuries ago, however, the POSTS, BARRACKS, QUARTERS AND HOSPITALS. 407 xsn w .:M ^ 1 M N . N M Fig. 187.— Modem Arrangement of Buildings in a Garrison Sta- tion of Infantry, French Army. A, B, barracks ; C, canteen ; X), store-house ; B, stables ; O, kitchens ; H, mess-balls ; I, infirmary; K, bath-bouses; L, latrines; U, urinals; M, guard houses. necessity for constant military preparedness caused the establishment of large permanent forces ; while the more rigorous standard of discipline in- troduced rendered it still further necessary to bring soldiers together for habi- tation and control. The barracks at first erected, as devised by Vau- ban, were large, and planned with special reference to economy of space. They were of several stories in height, and were built around the four sides of a square court-yard ; entrance being had at the corners. They were imposing in ap- pearance and capable of excellent use for defence. The men were kept well in hand, communication by the central corridors and inside porches was easy, and .the enclosed court was ad- mirable for military exercises. From the point of hygiene, however, their defects were both numerous and grave ; the central court-yard was damp, not exposed to air currents, and badly sunned ; two sides of the barrack neces- sarily had an undesirable exposure ; the latrines, kitchens, hospital and other accessory institutions were in the same building, and with mounted troops the horses were stabled* on the ground floor of the barracks — the last condition not being entirely done away with at the present time in the barracks of cer- tain armies. Some of the barracks built on this plan were enormous, several accommodating 3,500 men, and one, at Lyons, holding 5,000 men. An epidemic once started in a bar- rack of this size and character could not fail to be severe, and buildings of such nature were soon justly regarded as unhealthful. In spite of this fact, square en- closed barracks have from time to time been erected in the French, German and Italian services, and such were recently built for the accommodation of Spanish troops in Cuba and other colonies. A modification of the original type of Vauban barrack consisted in locating four linear, but de- tached, buildings in the form of a square; leaving the corners open rnrmnn LTTTTTTTTTTTI FIG 188.— Ground Plan of Original Style of Barracks, as Devised by Vauban. (After Putzeys.) 408 THEOEY AND PRACTICE OE MILITARY HYGIENE. to permit of the circulation of air through the court-yard. In these bar- racks the galleries were left off and greater attention was given to ventila- tion — as a result they proved much more healthful. To avoid the disad- vantages of an iaterior court and the bad orien- tation of a part of the barracks, about the mid- dle of the present cen- tury a linear type of bar- rack was introduced; this plan being much used abroad. It was later found to be inconveni- ent from the necessity of having the kitchens, lavatories and latrines in the main building — as it was originally planned-^and these ac- cessories were then put ia additions extending from each wing. While very convenient for the double or single company barracks used in our own service, this latter ar- rangement also proved unsatisfactory in foreign armies, in which a large number of men are ha- bitually quartered t o - gether. A linear plan of barrack was then resorted to, containing merely the quarters of the men, while the kitchen, lat- rines and lavatories were put in detached buildings. This, in general, is the plan at present employed in most modern barracks abroad; but the barrack buildings used in the British service are chiefly pavilions, having a capac- ity of but one company, while on the continent these buildings are large and substantial structures. In the German army, the newer type of bar- rack has accommodations for a battalion. POSTS, BAEEACKS, QUAETERS AND HOSPITALS. 409 In the British service, a revolution ia barrack construction occurred as a result of the investigation of conditions in that army immediately after the Crimean War, an example which other foreign nations have strangely been somewhat slow to follow. During this investigation, aU the barracks in the United Kingdom were examined and many were found very defective. The death rate among troops in barracks at that time was 17.11 per thou- sand strength ; while among the civil male population between the ages of twenty and forty it was 9.8 per thousand, or about one-half. The beneficial results of improved barrack construc- tion and management were speedily shown in the greatly diminished mortality and sick- ness among the men; and in 1876 the mortality among troops had been reduced to nearly 2 per thousand less than that of the military class in civil life, while the amount of hospital accommodation necessary for troops was de- creased from 10 to 6 per cent. The modern British barrack is most simple in its construction, being of one or two stories in height and containing on each floor a single squad-room, sergeant's room, lavatory and night- urinal. For a regiment of infantry, thirty such barrack units are re- quired. Each squad-room is 77 feet long, 21 feet wide, and 10|^ feet high; affording 600 cubic feet of air space and 57 feet of superficies to each man. Five square feet of window space are allowed per capita ; meas- urements being taken within the inside bead of each frame. The beds are placed in pairs between the windows. These buildings, when placed lon- gitudinally in parallel rows, are required to have a clear distance between them equal to at least twice the height from the ground to the eaves. In the French army, a modified form of the English pavilion barrack, devised by Toilet, has been tried in the garrison at Bourges and has Fig. 190.— Transverse Section of Toilet's Pavilion Bar- rack, as Used In the French Army. i;i|- -ij- Fig. 191.— Ground Plan ol Toilet's Pavilion Barrack, as Used in the French Army. given much satisfaction ; in spite of which, apparently from financial rea- sons, it has not been generally adopted ia the French service. Such barracks are built of brick and iron, and have a special arrangement of the roof and inner wall designed to prevent extremes of temperature and to facilitate ventilation. The outer walls are built of solid brick, the inner of hollow 410 THEOEY AND PEACTICE OF MILITARY HYGIENE. Route Nationale N° 153 de Bourges a Dun le Roi . 1" ■;:.■ -I - c — ^-1 - -/ -.1 I- •.■'■■■' I Jl il Life ^ I VM'-y-w/A r-y/.^k-.A r.-., . .--.J r- --.'7,'! 2^ ^,^7"7^r»l FT-^'^ra 43- -o- polygone ^-^— C^3 KU- „v brick ; between the two being an air space of about five inches thickness. The floor is covered with cement or bitumen and is raised about two feet from the ground; the latter, under the buildmg, being given a coating of concrete. The pavilion is extremely simple in (JetaU, as shown in Fig. 191. The air space per man, allowed in these barracks, is 775 cubic feet. This pavilion system of barracking troops is regarded with much favor by foreign sanitary officers. In services which still use larger and more solid barrack buUdings under ordinary circum- stances, the pavilion sys- tem has been adopted for the permanent camps of instruction already noted. In our own service the character of accom- modations for troops varies with the post. The material entering into the construction of barracks has largely de- pended upon availabil- ity; while the plans of the buildkigs, in many cases, have had particular relation to existing mili- tary necessity and con- siderations of economy. While some barracks are well built and are excel- lent in character and condition, others were hastily constructed, es- pecially at western sta- tions, from poor material and without proper ref- erence to ventilation or other sanitary require- ments. After several decades of use a number of these buildings have be- come unfitted for occupation; and from such stations there are constant complaints of overcrowding, defective ventilation, bad construction, in- sufficient means of heatiag, undrained sites, leaky roofs and general dilap- idation. In some instances, needed repairs and alterations have not been made, on the supposition that the post would soon be abandoned; yet the latter has sometimes been continued, from year to year, for considerable periods. A steady improvement in the sheltering of troops, however, has gone on during the past ten years, partly by the construc- tion of new posts but more especially by the abandonment of old ones ; as many as a dozen stations having been discontinued in a single year. At present, as a general rule, the barrack buildings of our army may be considered to be in passable sanitary condition — being comfortable. .J BH-IQIIIiiir ill 0' Route ES3, ■/' r 181 ^ BM Fig. 193.— Arrangement of Frencli Barracks, Pavilion System, at Bourges. a, b. Entrance pavilion ; c, Mtchens ; d. Infirmary ; 6, latrines ; /, guard house ; g, canteen ; li, stables ; n, lavatory. POSTS, BAERACKS, QUARTERS AND HOSPITALS. 411 clean and fairly well ventilated. There are nevertheless certain excep- tions to this rule, and it is undeniably true that the habitations of our soldiers have not in the past received the attention which they de- served. With respect to barracks, equally with other matters, a false economy has considered many things as luxuries for soldiers in garrison — and hence to be gone without — which are regarded as necessities in civil life. This attitude is much to be deplored, particularly since the military spirit strongly tends to Itmit complaiot and criticism on the part of those Fig. 193. — First Floor Plan of Artillery Barrack for One Hundred and Twenty Men. most concerned, and favors unquestioning acceptance of what may be offi- cially provided, regardless of character or quality. Economy was formerly long too much of a watchword among those having the supply of our army in charge; they apparently overlooking the fact that the train- ing of a soldier necessarily represents a large financial outlay, and that below a certain point, irrespective of humanitarian considerations, diminu- tion in expense of maintenance means an increased and disproportionate wastefulness of life, health and efficiency. In this connection it may be added, also, that in view of past mistakes in construction no buildings in- tended for occupancy by troops should be erected by the construction 412 THEORY AND PRACTICE OF MILITARY HYGIENE. department until the plans have been examined and approved by a sani- tary expert. It may be accepted as a general rule that where barracks are not of the best character the sick-rate will be proportionately high. The habitations which have been erected within the past few years for the shelter of our troops are excellent in their internal arrangements, and the later plans leave but little to be desired. The recent change from double sets of barracks to those accommodating a single company is much Fig. 194.- -Second Moor Plan of Artillery Barrack for One Hundred and Twenty Men. to be commended. The general plan of these new barracks is a main building with one or two wings. The former arrangement is preferable, as being more compact, convenient and better exposed to sun and air. The new artillery one-company barrack, capable of holding 120 men, lately adopted in our service, is far superior to anything of the kind provided in foreign armies. This barrack, however, like nearly aU those lately erected, has the lavatory and latrine in the main building on the basement floor. Although these fixtures are so located as to be exposed to light and air on three sides, yet their location in the main building at aU is to be depre- cated. They are best placed in a detached structure, reached by a covered POSTS, BAEEACKS, QUAETEES AND HOSPITALS. 413 way for shelter in stormy weather. The general arrangement of the biiild- ing, however, is admirable from the standpoint both of hygiene and con- venience. The central hallway affords great assistance in ventilation. The 1899 plan of barrack for 100 men, with two wings, is far less desirably arranged. The latrine and lavatory are beneath the mess-room, and the squad-room on the first floor can be reached only by passing through the day-room. While the squad-rooms on the upper floor have the advantage of containing but two rows of beds, they are much too large and shelter nearly twice as many men as should be placed in a single room. Where 414 THEOEY AND PEACTICE OF MILITARY HYGIENE. such large squad-rooms are employed, the men occupying the bunks nearest the door are at a great disadvantage from the constant passing in and out. The men themselves also much prefer smaller squad-rooms, through the greater opportunity for comparative privacy and more congenial association which is thus afforded. In general, squad-rooms should he sufficient to accommodate not more than twenty to twenty-four men. General Principles of Barrack Construction. — In considering the construction of barracks, only those poiuts which have a weU-recognized iafluence upon the health and welfare of their occupants will be discussed; POSTS, BAEEACKS, QUAETEES AND HOSPITALS. 415 nor can these, in a work of this character, be gone into in detail. Barrack construction is a subject of such magnitude and importance that to treat it fully in all its phases would require a special volume. The barracks now being erected in our service have walls of brick, stone or wood. In a few of the old posts, log barracks or those made of adobe are still in use. The material of which barracks are built is not, however, a matter of small importance. Walls should be non-conductors of heat and cold ; and the substances of which they are made should be as carefully chosen as those for clothing, which serves a similar purpose with reference to the individual. Bricks are undoubtedly superior to all other materials for barrack construction — in every part of the country and under all circumstances. They are light, cheap, readily made, easily handled and durable. They are very retentive of heat, from their porosity, in the ab- sence of wind; but this very porosity becomes a fault in heavy storms, when air and moisture may be forced through them. In fact, so much is this the case that it is desirable, in aU brick walls, to make these of suffi- cient thickness to include a layer of mortar. Bricks absorb water readily and hence should not come in direct contact with the soil; an ordinary brick is capable of taking up about one-sixth of its weight of water, though very hard bricks take up less. For partition walls, bricks are excellent. Stone walls have the advantage of strength, durability and sightliness ; but are porous and absorbent of water, though less so than brick. Galton showed that, as regards heat, the conductibility of marble was twice that of freestone, four times that of glass, six times that of brick masonry and more than seven times that of plaster. Experiments made by Put- zeys gave similar results. It is therefore evident that the Spanish style of building — brick walls with stucco outside finish — is admirable not only for hot but cold climates. A frame wooden building is, in general, merely a cheap substitute for something better, and it is to be regretted that buildings of such material are being erected for the shelter of troops in garrison. They are comparatively cold in winter and hot in summer, and are very combustible and liable to deterioration. Logs will probably be no longer used for barrack walls except for small isolated stations in Alaska. When used for such a purpose, they should be peeled and squared, for roimd logs and chinking are a poor dependence. Adobe walls may be used in regions where there is little rain. Buildings constructed of this material are warm in winter and cool in summer. They are very absorb- ent and soon become contaminated with organic matter; and if there is much sand in the dirt from which they are made, insects are svae to work into them. Cellars usually add much to the healthfulness of a barrack, but the level of the ground water should lie at least four feet below the cellar floor and the latter should be rendered impermeable to moisture and ground air. In addition, the cellar must be well ventilated. In cellars which are not floored with some impermeable material, the ground air gains ready en- trance — being forced upward by a rise in the ground water or drawn up by aspiration into heated dwellings. In buildings without cellars the air is apt to be damp and musty, but a damp cellar is worse irom a sanitary standpoint than none at aU. Under certain conditions the under-draining of cellars may he necessary, but where this is actually required the site is 416 THEOEY AND PRACTICE OF MILITAEY HYGIENE. ■^b «-cl undesirable. To best prevent dampness and the rise of ground air in cellars, a layer of clay about one foot in thickness should be spread over the bottom of the excavation, and this should be covered with a layer of concrete, whUe a coating of asphaltum is added over aU. This method, however, is somewhat expensive, and in our new barracks reliance is had on a single layer of concrete four inches in thickness. In damp soils this is certainly insufficient. Barracks without cellars should be elevated suffi- ciently above the ground to permit of ready inspection and policing of the space -underneath, without the necessity of taking up the floors. This space should be well ventilated and should have a flooring of concrete. The latter requirement is rarely carried out in our service, in spite of its importance. Foundations should be suffi- ciently solid and deep enough in the ground to give strength to the building. Where the ground is soft, or a solid foundation cannot be reached, the walls should be on a platform of at least four times their breadth. For this purpose concrete foundations are far preferable to those of stone, since they prevent moisture from rising by capOlarity from the ground into the walls and thus rendering them permanently damp. The base of the walls should be expanded into footings ; the lowest course of which should be twice the breadth of the walls, while their height should not be less than two-thu-ds of the wall thickness. It is of great importance that the portion of the walls below the sur- face of the ground should be free from dampness. In our own service the effort is made to accomplish this by coating the outside of the wall with cement plaster, filling in the excavation outside the walls with stone fill- ing, and under-draining below the foundation level. A better method, much used in England, consists in exposing the lower walls to the air by excavating the earth around them to the level of the foundation. This excavated space is walled on the outer side and under-drained ; but unless protected by gratings or railings such excavations are inconvenient and a source of danger. Sometimes the surrounding air-space is made very nar- row, and merely serves to prevent the main wall from taking up moisture by capillarity. Another method calls for the isolation of the wall by a broad air-space going several feet below the surface, the lower portion of the waU being prevented from absorbing moisture by an outside layer of cement or asphalt and sometimes by a narrow air-space. The part of the wall below the ground is built double in some foreign barracks. The outside portion is cut off from the inner waU by an air chamber, while moisture is prevented from rising into this inner wall by damp-proof courses. Asphalt plates, fastened together by heat, are strongly recom- FiG. 197 — Method ot Flooring Cellars to Prevent Dampness, a. Disconnected air-space lined wltli cement ; 6, asphalt ; c, concrete ; d, clay. POSTS, BAEEACKS, QUAETEES AND HOSPITALS. 417 iipf?iK2^ -^' Fig. 198.— Method ol PreTenting Dampness of Walls. Letters D denote location of damp-proof course. mended by Putzeys for protecting ground walls and cellars from soil moisture. Walls above groimd draw much moisture from the portions below the surface, unless special, measures of prevention are taken. These usually consist in inserting damp-proof courses in the walls about six inches above the groimd ; these courses consisting of any suitable material impervious to water. Usually slates, embedded in hydraulic cement, are employed ; some- times sheet-lead is used, or hollow tiles or perforated vitrified brick. On internal walls the damp-proof courses are usually laid at the level of the concrete flooring. Above ground, also, walls take up considerable moist- ure. Against such dampness hollow external walls are the best protection. These walls consist of two thicknesses separated by an air space two or three inches iu width ; better located nearer the external than the internal face of the wall and extending completely around the buHduig, including the corners. These two thicknesses should be bonded together with iron, for bondiag of brick readily transmits moist- ure by capillarity. A damp-proof course is needed at the top of exposed walls, such as parapets and chimneys, to prevent storm water from soaking downward through the masonry. This is usually provided by finishing the top with stone and letting it project an inch or two over the side ; or else having a damp-proof course of slate laid iu the masonry at its junc- tion with the roof. Many water-repellent combinations for coating the outside of walls have been proposed, but ordinary paint is very efficacious for this purpose. Where double walls are buHt, no other measures for securing dryness are, however, required. In the construction of our barracks soHd walls are used, the lathing and plastering being furred out two inches on the inner side. This arrange- ment does not by any means give the best results as regards dryness of walls, but is cheaper. Dampness in walls greatly favors conductibUity as regards heat-, as well as having a relationship to the development of micro-organisms. The subject has therefore both an economical and sanitary impor- tance, since damp barracks require an ad- ditional expense for heating and favor catarrhal and rheumatic affections and tu- berculosis. The construction of walls also has a strong influence upon conductibUity f'^^^m^m mr- FiS. 199.— Method of Preventing Damp- ness of Walls. Letters D C denote lo- cation of damp-proof courses. 418 THEORY AND PRACTICE OF MILITARY HYGIENE. of heat, and with equal thicknesses a hollow wall transmits heat much more slowly than if solid. It is true that the construction of double walls implies a slightly greater original outlay ; but this is ultimately much more than saved by resulting economy in healring, and it is impor- tant to remember that in cold climates proper ventilation and sufficient warmth caimot be combined with undue cheapness of construction. This point is emphasized by Carpenter, who gives the following figures for the amount of heat, expressed in British heat units, passing through solid and hollow walls ; per square foot of area, per degree difference in temperature and per hour : Thickness of wall In Inches. Single wall, brick or stone. Wall with air space, brick or stone. Thickness ol wall in Inches. Single wall, brick or stone. Wall with air space, brick or stone. 4 8 13 16 0.43 .37 .33 .38 0.36 .80 .35 .31 18 30 34 38 0.36 .35 .34 .33 0.19 .18 .17 .15 In winter, the air of the non-conducting space between walls should be confined, so as to limit the convection of heat by air currents. In sum- mer or hot climates there should be some means of escape for the heated air, especially at night, and it is advisable to make openings above and below which can be shut during the day, or when low temperatures prevail. With single thick walls, in cool weather, the layers of air which come in contact with them are rapidly cooled down, with resulting condensation of their moisture and dampness of the room. In general, the thickness of bar- rack walls is determined by the size and height of the building rather than other considerations. Very thin walls do not properly protect agaiast heat and cold, but unnecessarily thick masonry unduly increases the cost of the structure. No wood-work should be placed in a barrack except where absolutely necessary for carrying the floors or roof, or fixing the fitments of the build- ing. In the German barracks of recent construction no wood enters into the walls. Where wood is used, it should be so arranged that its shrink- age or decay will not affect the strength of the waU, and where the timbers receive support they should rest on stone templates with space for ven- tilation around them. No part of the wall should rest on them ; nor should they be run into chimneys on account of the danger from fire. Iron could with advantage largely replace timbers in barracks ; being not liable to com- bustion, decay, or impregnation with organic matter. It has, however, the disadvantage of rendering floors somewhat more conductive of sound. The method of constructing floors and ceilings is of much importance in retaining heat. In cold cUmates, where the floor is of poor character, it is difficult to secure anything like evenness of temperature in a room. In the roughly constructed barracks of the abandoned post at Poplar Eiver, Montana, the temperature during winter was noted as 30° F. higher at a point six feet above the floor than at the level of the latter. For ordi- nary purposes, wood is the best material for flooring. The material should be of good quality — ^hard wood, if possible — and should be tongued and grooved. If the latter material is not used, open seams invariably result POSTS, BAREACKS, QUAETERS AND HOSPITALS. 419 from the unavoidable shrinkage of the lumber. Fire-proof floors are made of iron beams embedded in cement, on which is laid a solid wooden floor-sur- face. These are now always put into German barracks. In certain French barracks, movable floors, made of boards tongued and grooved at the ends as well as the sides, have been used to facilitate cleansing of the under- spaces. Such an arrangement is both imnecessary and undesirable. With wood floors, skirtings are employed to hide the joint between the walls and floor-boards. They are preferably let into a groove in the floor, thus preventing draft and the accumulation of dust. Floors of cement or tile are too cold for northern climates, though admirable for the tropics. Cement gives rise to a highly irritating dust, while tile and mosaic soon become rough and uneven. Bitumen has been recommended for floors, as not wearing readily and being easily repaired. For lavatories and latrines the best flooring is the so-called "terrazzo," consisting of small pieces of marble laid together in cement and then smoothed down. A latticed wooden standing-board may be placed over it where required. The height of the ceiling is a matter of great importance in barracks, since low-ceiled rooms are hot and close. For temperate climates the height of the ceiling should be about twelve feet ; for warm climates four- teen or fifteen feet. If the height be too great, much difficulty in warm- ing will be experienced during winter. The space lying between the floor and ceiling of consecutive stories is often a somrce of danger in barracks of old or improper construc- tion. It being desirable to prevent the passage of heat, odors and sound, builders not rarely partially fill the spaces between joists with so-called pugging; usually composed of plasterers' rubbish, but sometimes of sawdust, tan-bark, chopped straw or similar substances. All these are inflammable and liable to decay, and . hence are objectionable. Fmrther, these interspaces may afford lodgment to pathogenic micro-organisms ; and even if the material used for filling be originally clean, it soon becomes in- fected. Dust, bacteria and moulds sift in through the cracks, often in large quantities. Water used in washing the floors percolates through, caiTying organic matter with it; and in the warmth, darkness, and stag- nant air of the underlying space the bacteria find conditions favorable to their development. Later they may be driven back into the barrack- room by air currents resulting from agitation of the flooring; and thus, even if the floor itself be clean, dangerous sources of infection to inmates may be constantly close at hand. Putzeys states that in some cases the soil in the vicinity of latrines is no more dangerously contaminated than the material found between the floors of barracks. Notter found large collections of organic debris under floors ; and Uffelmann has reported an instance in which a cubic meter of material removed from such spaces, weighing 1,510 kilograms, lost by calcination 118.5 kilograms — ^not con- sidering 24 kilograms of water — and contained 1,718 gm. of nitrogen and 508 gm. of nitrous acid. Laveran states that the tearing up of floors in old barracks has apparently often given rise to outbreaks of disease. To , prevent these interspaces from being a source of danger they should be orginaUy clean and free from all foreign matter. The flooring should be double, with tight seams; the upper layer being of tongue and groove boards running at right angles with the lower layer. Between these two 420 THEORY AND PRACTICE OP MILITARY HYGIENE. layers there should be a thickness of heavy water-proof builders' paper, with the edges of the strips well overlapping. The interspace is thus com- pletely shut off from the room above. Where flooring is laid above earth the same arrangement should be employed. The subjacent space should not be too small, and should be kept dry, carefully policed and well ven- tilated. New flooring should never be put down over old floors, which are worn, filthy and often infected. To do so is to preserve the dangerous qualities of the latter. Slates furnish the best material for the roofing of barracks. They should be smooth, hard, but not brittle, and give a metaUic resonance when struck. They should not take up water readily, and when stood on edge in water for half their depth, for several hours, the water should not rise to the top. In laying slates they should overlap two or three inches; the flatter the pitch the greater the overlapping required. Large slates are usually laid at a slant of 22°, while an angle of 26° is required for smaller slates. The roof should be boarded over and covered with heavy builders' paper before the slates are put in position, the paper rendering the barrack cooler in summer and warmer, in winter. Corrugated iron, zinc and tin roofs are not suitable for barracks through their great conductibihty for heat. According to Grimzweig, if the conductibiUty to heat of a roof made of wood and cement is 100, it is 265 when made of corrugated iron. When made of double planks separated by a layer of air of 30 millimeters thick- ness, the conductibility to heat is 99; while where tiles are used and are made to overlap three times in one foot the conductibility to heat is but 58. From this it is apparent that tUe retards the passage of heat more than four times as much as does corrugated iron, and is hence far superior for use in barracks, especially in hot climates or the tropics. Where tiles are used, a slant of 45° is required to give the best results in shedding rain. Tiles should be well baked, hard, and as little absorbent of moisture as possible. If zinc or tin roofing is employed, their faults as regards the con- duction of heat may be to some extent overcome by a double roof, with ventilation of the interspace. Such metal plates may be laid nearly flat, at an angle of only 4° to 5°, with their edges overlapping to allow for ex- pansion and contraction. Shingles should not be used for the roofing of barracks where better material can be obtained. As to form, the mansard roof is of much value in protecting the remainder of the building from extremes of temperature. The space under this roof, however, is unfit for occupancy by troops. Defects in roofs are a frequent cause of dampness, and these are especially liable to occur around chimneys and partition walls. Gutters in such places should be of lead. Eaves are finished in different ways. They should always be provided with gutters to throw the rain well away from the walls, and where the latter are not given consider- able slope — ^which is unsightly — they must be larger than would other- wise be required. Drain pipes from the gutters must be fastened weU away from the wall, to prevent soakage of the latter should the pipe break or become clogged. Such pipes should never be connected with groimd drains or sewers, but should discharge over a grating in the open air. Chimneys should be higher than surrounding buildings, so that their draft may not be in any way interfered with. Each fire should have its separate flue clear to the top of the buLlding. This should be circular. POSTS, BARRACKS, QUARTERS AND HOSPITALS. 421 as straight as possible, and smooth and plastered inside. Iron castings are sometimes used to line flues, these separating the flues from the house- structure and maiutaiaing a better draft. The number and size of windows to be placed in barracks must depend to a considerable extent upon climate. Usually there should be one win- dow to every two beds, equaUing in area one-eighth to one-sixth of the wall space. Windows are always to be placed opposite to each other, and should run from a point about 3^ feet above the floor line nearly to the ceiling. The upper sash should be freely movable ; and may, in warmer stations, be made 80 as to swing inward. Windows are weak points in the structure of bar- racks in cold climates, having a high diathermancy. For such climates, double windows and doors should always be provided, and the distance be- tween these also notably affects the loss of heat. The German Government has adopted the following for loss of heat by windows : Heat transmission in British heat units — per square foot, per hour and per degree differences in temperature — 0.776 for single windows and 0.518 for those provided with double sashes. These figures are increased by ten per cent, for very exposed situations. The actual economy in heating by furnishing storm windows to barracks is evidenced by the above. Sometimes double panes of glass are set in the window frames to retain heat, but these are quite inferior to double sets of sashes for this purpose. For summer use or hot climates, screen doors and windows are a sanitary necessity. .The men must be able to eat and sleep in peace and comfort; besides which flies and mos- quitoes play important parts in the dissemination of certain diseases which are especially prevalent and fatal among soldiers. At warmer stations, galleries on the southern exposure of the barracks are essential. For the inner finishing of barrack walls nothing has been foimd more satisfactory than lath and plaster, furred out from the main walls at a dis- tance of two inches. Ordinary plaster, however, has many disadvantages, being porous and readily absorbent of moisture and organic matter. Such plaster is used in most foreign barracks, but is scraped and whitewashed every six months as a sanitary precaution. This latter practice should be adopted in our service for aU old barracks. While walls should be of porous material on account of their lesser conductibUity as regards heat, it is none the less true that their surfaces should be non-absorbent. For the outer surface such a quality is valuable as largely preventing the penetra- tion of atmospheric moisture or storm water. For the interior aspect im.- permeability is also important ; since it has been shown by Vallin that the .close and often offensive odors found in some barracks depend chiefly upon the impregnation of porous walls and floors by organic matter, deposited upon these cold surfaces as the result of condensation of the vapor given off from the breath and other sources. While organic contamination in this manner is at no time great, it is carried on indefinitely and the results are ultimately marked. For these reasons, efforts looking to the rendering oi walls impermeable should always be made. In many of our new bar- racks adamant plaster is used, as being harder and less porous. The soap- stone iinish, a superficial layer composed of two parts plaster and one of soapstone, is hard, smooth and may be washed. Several proprietary prep- arations, capable of being applied by either brush or spray, are now used to harden plaster walls and render them less absorbent. Oil paints. 422 THEORY AND PEACTICE OF MILITARY HYGIENE. varnish and asphalt have been much employed for the same purpose. Laveran recommends the use of paraffin dissolved in petroleum or turpen- tine. Eough-finish plaster waUs should never be allowed ia barracks, as serving to catch and retain dust and bacteria. Wainscoting, about bar- racks, is to be absolutely condemned ; being absorbent of odors and organic matter and soon becoming infested with insects. The corners of barrack- rooms should invariably be rounded to facilitate cleansing ; not only at the junction of walls, but als'o where the walls meet the floor and ceiling. This rounding need not be excessive to answer all purposes. Arsenic is not infrequently found in certain colored paints, especially various shades of green. These should not be used about barracks; siace the arsenic is liberated in combination with the hydrogen of the air, and when respired may produce chronic arsenical poisoning. Zinc paints ap- pear to be more durable than lead paints and possess no toxic qualities. SUicate paints have been recently introduced and are said to be very sat- isfactory. The so-called " duresco " hardens the surface to which it is ap- plied, can be washed, is not toxic and repels moisture. Barrack Furniture and the Care of Barracks. — ^The furniture of sqtiad-rooms includes shelves and hooks for clothing, lockers, beds, bed- ding, chairs and gun-racks. Shelves, usually double, are provided in nearly all barracks. They afford a convenient and, in fact, the only practicable place for keeping the more bulky articles of the uniform, and are much appreciated by the men. Usually of such a height as to permit the clothing-hooks to be hung below, their upper surfaces are thus not readily open to inspection. From this fact, accumulations of dust are liable to occur upon them, these to be later disseminated by brushing or by currents of air. To prevent this they should be wiped off weekly with a damp cloth, all articles being removed from them for the purpose. That such cleansing has been properly carried out is readily determined by touch with the white glove. In many bar- racks, company commanders have authorized the use of pieces of colored cloth, tacked on the upper shelf to hide the lower shelf and the garments hung below it. This custom should be opposed as favoring stagnation of air, a lack of order and the possible retention by the men of articles unde- sirable in a squad -room; and in addition such curtains themselves soon become soiled, dusty and unsanitary. The latter faults might be partially remedied by frequent washing, but this will in practice rarely be carried out. Lockers afford security and a convenient means of caring for the smaller articles of clothing and personal property. They are chiefly sup- plied in the form of low wooden boxes, with a single tray, capable of being pushed under the bed. In the barracks of later construction, however, lockers are built against the wall in the form of small closets. These usu- ally soon become infested with vermin; and being fixed, they cannot be removed for sunning and cleansing as can the box lockers. From a sani- tary standpoint they are much less desirable than the' latter. Lockers re- quire careful inspection, since soiled and damp clothing is often kept in them to the detriment of clean apparel. Barrack bags, of brown cotton duck, are now supplied as receptacles for soiled clothing prior to washing. They are excellent for this purpose, but POSTS, BAREACKS, QUARTERS AND HOSPITALS. 423 must themselves be frequently washed, since otherwise in hot weather they become odorous and are apt to afford lurking-places for insect para- sites. This washing is, xmfortunately, rarely performed. Much improvement in the sleeping arrangements of soldiers has been made of late years in all armies. This is particularly noticeable in our own service, which is far better equipped, in this respect, than are those of foreign nations. Not fifty years ago, in the British army, even at tropical stations, wooden bunks were usually built in several tiers against the walls of the barrack building. At other barracks in Eng- land there were large beds, in which four men were compelled to sleep together ; a requirement naturally conducing to dirt, disorder and im- moral practices. At the present day, in the French army, the beds are double, and two men must sleep together. This practice is unsanitary and is repulsive to the better class of men. In our own service two-tier double bimks were used until a comparatively recent period, their abolition being a great sanitary advantage. The British soldier at Hong-Kong provides his own bedstead, a custom long prevalent in the British service iu India. It is remarked that as a result of this custom uniformity in appearance is lost, an imdue amount of barrack space is occupied and the existence of insect parasites is favored. At present, cot-beds of two patterns are supplied in our service. One consists of iron trestles supporting an elastic framework of slats. This pattern is not comfortable, and should be entirely done away with as being difficult to clean, absorbent of odors and retentive of vernun. A double bed very similar to this bunk is used in the French army. Comparatively recently a single bed, made of iron throughout, with woven wire springs Fig. 200.— Barrack Bag. Fi8. 201.— Composite Bunk. and mosquito frames, has been supplied. This is weU adapted to military uses and is far superior to similar articles supplied in other armies. It is comfortable, soHd, substantial, sightly and readily cleaned. The pres- ent method of fastening the woven wire, with a wooden cleat at the end of the frame, is undesirable, however, since it affords a refuge to bed-bugs from which they are dislodged with difficulty. The bed also might with 424 THEOEY AND PEACTICE OF MILITAEY HYGIENE. advantage be made two inches longer, and in damp localities the woven wire fabric sometimes rusts. This latter fault can be prevented by care and an occasional wiping with a rag slightly moistened in mineral oil. Beds should be thoroughly overhauled and cleaned whenever vermin ap- pear to be present. The wire netting should habitually be well brushed, in the open air, once a fortnight. In barracks' the heads of beds should be kept at a distance of six inches from the wall. A large number of folding canvas cots, as described in a previous chap- ter in connection with their field use, have been lately supplied to troops in the tropics. They are comfortable and convenient, but, although excellent in camp, they can by no means replace the bed just mentioned for barrack use. Hammocks have been recommended for military purposes. These are much less comfortable than beds, and economy of space is by no means as FIG. 202.— New Model Bunk. essential in permanent habitations on shore as on ship-board. In any squad-room where such economy of space appears desirable it is evident that over-crowding exists. In this connection, mention may be made of bed-bugs, which, once in- troduced into a squad-room, multiply rapidly in the cracks and crevices of the waUs and floor, the beds and beddiag. A large number of eggs are laid at a time, hatching being accomplished in ten days and maturity being reached in about seven weeks. These insects are very long-lived, and have been shown to be capable of existing without food for over a year ; hence old barracks, long unoccupied, should be carefully gone over before being used by troops. Swallows' nests and old cottonwood logs appear to harbor an allied species, if not the same insect. Bed-bugs are of no small sanitary importance from the fact that by their persistent attacks soldiers are deprived of much needed repose ; and when these insects are crushed on walls or bedding they leave unseemly smears and give rise to unpleasant odors. Further, there is some evidence as to their being capable of transmitting disease from the sick to the well by their bites. When once introduced into a squad-room, bed-bugs can be kept under only by constant effort, especially in warm weather. To fur- nish few hiding-places for these pests, beds should be made of iron, and so POSTS, BARRACKS, QUARTERS AND HOSPITALS. 425 constructed as to be readily taken down for cleansing. Floors should be rendered impermeable, and the cracks fiUed up, by one of the methods subse- quently described. Walls should be plastered; avoiding waiascoting as above aU certaia to afford a ready harboring-place, from which the dis- lodgment of these insects is difficult or impossible. In log barracks or those constructed of adobe, their extermination becomes a matter of the greatest difficiilty ; their almost inevitable presence causing much discom- fort among the inmates. For the destruction of bed-bugs frequent shakiag, beating and sunning io the open air of all bedding, pillows and mattresses is required. Where their presence is noted in beds, the latter should at once be taken apart in the open air and scrubbed with hot water and soap- suds. The beds may then be gone over with an emulsion composed of one part of petrolermi to four parts of water, applyiog it weU with a stout brush. Both the bugs and their eggs are readily destroyed by this treat- ment. Scalding water may also be used for the same purpose. A satu- rated solution of bichloride of mercury is very efficacious if brought in contact with the insects or their eggs. Benzine and gasoline appear to de- stroy these vermin, in any stage of development, almost instantly. For cracks in walls the latter substances are best applied in the form of a spray, an apparatus for the production of which can be readily improvised by the aid of a bicycle pump or large syringe. When these substances are used in a squad-room, however, the latter should be closed to those not engaged in the work until the inflammable fumes are dissipated, which soon occurs. For articles which cannot be moved, pyrethrum or Persian powder has been much used; being insufflated into all possible lurking- places for these pests. This powder has no effect upon the eggs of the insect, and hence the relief afforded is only temporary in its nature. In addition, its use is not particularly cleanly. In the absence of a more de- structive agent, bed-bugs can be driven away from a bed by washing it with a mixture made by crushing the berries of the cedar tree in hot water. For satisfactory results, it is necessary that this liquid be applied weekly. Where a barrack has become generally infested, the insects are best destroyed by fumigation with sulphur dioxide. The entire building, how- ever, must be fumigated at the same time to prevent incomplete results from the passing of the bugs from one room into another during the opera- tion. Formaldehyde gas is not efficacious in the destruction of these pests. In general, the use of gaseous insecticides implies the complete evacuation of the building for twonty-four to thirty-six hours, and hence will not always be conveniently appKcable. It can, however, be readily carried out during practice marches or by placing the command under canvas at any time, and the thorough destruction of vermin thus ensuted is ample recom- pense for any discomfort incurred in the attaiament of this object. With respect to bedding, our soldiers are now supplied with mattresses, which would be all that could be desired for comfort were they a little thicker. It would be an advantage from the standpoint of economy and cleanliness if they were made in three equal parts, any worn or soiled portion being thus readily removed for condemnation. Mattresses should be thoroughly brushed in the open air and exposed to the sun at least once weekly. In the prevention of vermin, especial attention should be given to cleanliness of the folds and about the tufts. Mattresses should never 426 THEOEY AND PEACTICE OP MILITARY HYGIENE. be used without the cover provided. The latter should be washed at least every two weeks, and oftener ia warm weather. Bed-sacks are hominally issued ia our service, but in practice they are rarely used except for prisoners. For troops in semi-permanent camps their great transportability may at times commend them; and the same applies to their use in field hospitals. When mattresses are not supplied and bed-sacks are issued, regulations authorise the monthly issue of thirty pounds of straw, per man, for use as beddiag. In the German, French and British services the soldier still sleeps on straw, the allowance per man, in the last army, being twenty-four pounds per quarter. In the French army but twenty-two pounds of straw are allowed every six months. Both of these allowances would seem to be quite insufficient for proper cleanliness, since imless the straw is frequently changed it soon harbors insects. Bed-sacks, where used, should be washed at least monthly. The straw should be removed with care to avoid raising a dust, and should be at once burned. Frequent simniag and shaking is of great importance. The piUows supplied in our service should be made slightly larger, since when matted down by use they are too small and many soldiers FIG. 203.— Bed sack. habitually use rolls of clothing under them. This practice is undesirable. Clothiag more or less soiled by hard usage should not be brought into contact with a clean bed, nor is the appearance of these garments improved by the process. PiUow-sacks are supplied for use where bed-sacks are employed. The sheets provided for our troops are excellent. Those issued in the British army are said to be very coarse and unsatisfactory. Sheets should be washed at least once weekly, and this is usually accomplished in our service. In the British army the sheets are required to be washed once a month; in the French army they are washed monthly during the colder half of the year and every twenty days during the warmer months. In making the bed the sheets should be taken off and shaken, and when re- placed they should be transposed. Bed-linen cannot be kept properly clean ia the absence of personal cleanliness or where the men sleep in the underclothes and socks worn during the day. The latter common prac- tice should be discouraged and the men urged to provide themselves with pajamas ; or at least their underclothing should be changed and the gar- ments worn during the day spread out to aii-. Blankets are noticed elsewhere. They should be shaken in the open air and sunned as often as possible, at least once weekly. They should be washed when soiled, or under any circumstances as often as once a year; POSTS, BAEEACKS, QUAETEES AND HOSPITALS. 427 care being taken to prevent their becoming hard and shrunken as a result of the operation. Mosquito bars are now issued to troops in barracks, and these conduce greatly to rest and comfort. In addition, they probably do much to dimin- ish the frequency of malarial iafection. Since, during sleep, the hand or foot may come in • contact with the netting and thus be stung by mosqui- toes, the nets issued to malarious posts should have, as an additional pro- tection, a gathered valance sewed around the netting, about ten inches wide and extending six to eight inches above the bed level. No smaller mesh than in the nets at present supplied is required, except where buffalo-gnats and midges abound. Mosquitoes, however, will find any rent or opening, and hence as much of the net as possible should be tucked under the mat- tress when the bed is' made, leaving only sufficient slack to permit of entrance. Chairs and tables possess no special sanitary importance. Where suffi- cient chairs are not supplied, the men are perforce obliged to sit on their beds, a practice not conducive to the appearance of neatness in the squad- room. From the fact that a majority of the inmates of a squad-room will usually be absent, the present allowance of one chair to two men will ordi- narily be quite sufficient. In the German army a stool is supplied to each soldier. Tables are not a necessity in squad-rooms. Gun-racks and their contained fire-arms were long kept in squad-rooms. In more recent barracks, however, a small separate room has been provided for their reception, where they are kept in charge of a non-commissioned officer. This change is very much of an advantage, since additional space is thereby saved in the squad-rooms, and the atmosphere in the latter is rendered free from the odor of burned powder and oil. The greater diffi- culty in securing fire-arms will undoubtedly have an effect in reducing the frequency of homicide and self-destruction. Cuspidors are not supplied for the use of troops, but the necessity for their employment is vecogmzed and every barrack contains them. Usually they are found in the form of wooden boxes filled with sawdust or sand ; though sometimes tin containers, cut from the lower portion of empty oil cans, are employed. Wooden containers are soon saturated with expecto- jated material, become offensive to sight and smeU and cannot be properly cleaned. Both sand and sawdust, contaminated with sputum, may be dried and disseminated by accident or air currents. Where these are used, the determination of the frequency of cleansing is somewhat difficult for the inspector; and sawdust, from the danger of ignition from cigar and cigar- ette stubs, is a constant menace to safety. For these reasons it would be advisable to issue large, galvani^ed-iron cuspidors, so shaped that they wiU not readily upset yet may be easily cleaned. These should be kept par- tially filled with some disinfectant solution, and be cleansed and scalded once daily. Small pieces of linoleum or rubber mat should be placed under cuspidors to prevent inadvertent soiling of floors, and these should be washed and wiped off with a disinfectant solution daily. Spitting on the walls or floors in barracks should be prohibited, and any infraction of this rule severely punished. Indiscriminate expectoration is not only incompatible with the cleanliness of barracks, but ejected material not rarely contains the micro-organisms of tuberculosis, pneumonia, diphtheria. 428 THEOEY AND PRACTICE OF MILITAEY HYGIENE. or pyogenic bacteria; and when such material is dried, ground to dust under the feet of passers and then raised by sweepiag, air currents or other means, it may readily be inhaled and serve to determine the occurrence of these diseases in others. In our army the question of properly disposing of the sputum has not received the attention which its importance deserves. It is true that the presence of cuspidors is ■undesirable in squad-rooms and that the frequency of expectoration is largely determined by habit; but since no small proportion of soldiers are addicted to the use of tobacco, the necessity for providing for ejected saliva and sputum should not be offi- cially disregarded. Water buckets, filled with water for use in case of fire, are to be found in all barracks. These buckets should be emptied and refilled with fresh water at least three times weekly dm-ing warm weather. The water is soon contaminated with dust; and the accompanying bacteria, perhaps of pathogenic character, imdergo rapid development. During the mosquito season the eggs of these insects are preferably deposited in such receptacles, and their development may be subsequently a source of much discomfort. In winter, care must be taken to prevent the contents of these buckets from being frozen. Expectoration or the throwing of articles into them should be severely punished. Floors are an important agent in the causation of infections, and thus merit the careful attention of the military sanitarian. In barracks the floor is constantly being soiled; with saliva containing pathogenic micro- organisms ; with bits of food ; with mud and dirt which men carry in on their clothing and equipment and particularly on their shoes. It is there- fore not surprising that many investigators have found the dust and scrap- ings from barrack floors to contain the germs of disease. Tryde and Salo- monsen found typhoid bacilli on the floors of a barrack in Copenhagen; Uptadel at Augsbiu'g; Birch-Hirschfeld at Leipzig; Chour at Jitomir. Emmerich found the pneumococcus on floors in wards occupied by pneu- monia patients. Maximowitsch, experimenting with the dust of a hospi- tal, states that of twenty-one guinea-pigs inoculated, nine became tubercu- lous ; three times he found staphylococci, twice streptococci and once the pneumococcus. Comet had similar results. The infectious material is found chiefly in the cracks and crevices of the floor, but also on projecting ledges, shelves, and in corners. It is a comparatively small source of danger while quiescent, but when raised by currents of air, the feet of passers or by sweeping, it is widely dissemi- nated and its opportunities for producing an infection are greatly increased. Sweeping and dusting are the great agents in its spread, and such means of cleansing should be prohibited. The necessary cleansing is not only more safely but also more effectually done by the use of damp cloths and mops; the moistened dust being rendered incapable of rising, and hence being actually removed instead of being largely raised from one portion of a squad-room to be deposited over the floors and furniture at the other end of the apartment, later to be taken into the system as a result of contact or inhalation. In some instances, floors are cleaned by the wet method ; but this procedure, unless properly carried out, is not without serious faults. Ordinarily by far too much water is employed for this purpose. Unless directed to the contrary, soldiers wOl almost invariably dash it on POSTS, BAREACKS, QUARTEES AND HOSPITALS. 429 in bucketfuls — the floors subsequently requiring hours to dry even under favorable circumstances. In many instances, inspectors have found that holes had been bored through the floors and the dirty water flushed over them allowed to escape to the soil beneath, thus providing every facility for the development of bacterial life. In other instances, foul water, charged with organic matter and microbes, escapes through cracks iato the space between floors, keeping up a constant moistm-e, favoring the develop- ment of germs and inducing moulding and decay of the boards and joists. Damp floors have long been recognized by sanitarians as potent factors in the production of disease, more directly in the production of tonsillitis and pharyngitis. By line oflicers, however, the necessity for the use of but a small amount of water on floors is not generally appreciated, and a general order on this subject might well be promulgated. Floors should be cleaned with mops only slightly moistened, and these be frequently wrung out in buckets of hot soap-suds. The method is slightly more laborious, but it is also much more conducive to health. In the British army the wet scrub- bing of floors is prohibited at periods oftener than once weekly. During rainy or damp weather the use of any but a very small amount of water on floors should not be allowed. In order to use water more safely on floors, and at the same time to prevent absorption of organic matter and micro-organisms by the latter, all floors in barracks should be rendered impermeable. In this respect the United States army is behind those of many other countries, in which the desirability of rendering barrack floors non-absorbent is officially recog- nized. In our hospitals the necessity for this quality in floors has long been appreciated and satisfied, and the arguments in favor of it for such buildings apply equally to barracks. Aside from its sanitary value, the proper rendering of floors impermeable at once imparts an air of neatness to a squad-room which can be obtained in no other way, and at the same time diminishes futiu'e labors with respect to cleansing. Many methods have been proposed to render floors impermeable. Mangenot advises that barrack floors be given a coating of bitimien. This has been tried in the French army and fojmd to be somewhat cold during the winter, and in the hot season liable to soften under pressure, particu- larly under the legs of beds. It presents, of comse, an entirely impervious surface which can be readily washed and disinfected, and abolishes all danger of infection from the planking or spaces underneath. Waxed floors, as sometimes suggested, are too costly for military use and take up much dust. The wax also has to be renewed at frequent jJeriods. Among other methods, the use of linseed oil, tar and paraffine has been advised. In the German army, linseed oil is employed for this purpose. It is applied boil- ing-hot with a stiff brush, and, as far as impermeability goes, the result is satisfactory after several applications have been made. Subsequently the oil must be applied twice yearly. This method appears to have many disadvantages. The oil does not fill the cracks, dirt adheres to floors so treated and gives them a bad appearance, and cleansing is said to be diffi- cult. Further, floors soaked with linseed oil acquire a very disagreeable and persistent odor. In the French and Austrian armies it is ordered that the barrack floors shall be rendered impermeable by the use of coal-tar — a board of officers in the first named service having reported upon this sub- 430 THEOEY AND PRACTICE OF MILITARY HYGIENE. stance as giving the most satisfactory results for this purpose. A recent order in the French service directs that, for application, the tar should be mixed with boiling water in the proportion of 3 kilograms of tar to 1 liter of water. In this proportion it is said that the tar and boiling water tth'y readily, good results are obtained and drying is rapid. The mixture must be constantly stirred during the application, which is best performed with a stiff brush. The tar may also be applied pure, or mixed with turpen- tine. By its repeated application the cracks are gradually filled up. The color imparted is brownish and unsightly, but otherwise the method gives very satisfactory results. The best procedure is undoubtedly that depend- ing on the use of paraffine, as carried out in our own military hospitals. In this method the floor is cleaned and dried. It is then lightly covered with grated paraffine, and this is melted into the floor with a large hollow iron containing burning charcoal. Under such heat the paraffine penetrates the wood to about one-fourth of an inch. The excess of paraffine is then scraped off and the floor given one or more coats of a solution made by dissolving one ounce each of wax and paraffine in one quart of turpentine. Subsequent applications of this solution should be made once a month. Wood so treated becomes not only impermeable to moisture, but its cracks are filled up, it is hardened and less liable to splinter, takes on an agree- able appearance and is susceptible of high polish. While the best results are obtained with well-built floors made of good material, it is safe to say that there are no floors in our barracks which would not be improved, from a sanitary, aesthetic and economical standpoint, by the proper appli- cation of paraffine. Fleas not infrequently develop in large numbers on barrack floors dur- ing warm weather, and the discomfort which they cause is often consider- able. They have also been shown to play a part in the dissemination of bubonic plague. These insects are introduced into barracks by dogs, cats and pet animals; their eggs being deposited between the hairs of the host, but not attached to them, so that they are scattered by movements. They are especially common in the places most frequented by infested ani- mals. The life cycle of the flea, according to Howard, is complete in seventeen days ; the young developing in the dust in cracks or crevices of the floors. The eggs are not likely to hatch when disturbed. Prevention of annoyance from these insects depends upon exclusion of pet animals from squad-rooms during warm weather, the impermeabilization and fre- quent cleansing of floors, the use of pyrethrum powder and the mopping down of floors with strong bichloride of mercury solutions. Casemates. — Many casemates are still employed as quarters for troops, in spite of the adverse report of probably every medical officer who has had to do with them. They are dark, damp, ill- ventilated and mouldy, and such qualities cannot fail to have their effect upon sick rates. In the citadel at Ghent, in 1845-46, it is stated by Ordroneux that those troops which were lodged in subterranean apartments had twice as many sick as those quartered above the surface of the ground. At Fort Clarence, in England, it was shown that men quartered in casemates were twice as liable to. tuberculosis as those ia the ordinary buildings. In 1898, in our own ser- vice, it was found that at Fort Adams, for the previous ten years, the average annual rates for rheumatism were 84 for the part of the garrison POSTS, BARRACKS, QUARTERS AND HOSPITALS. 431 living ia casemates and 56 for the soldiers Kving in a light and airy bar- rack buildiag. For the previous three and one-half years the casemates gave 61, the barracks 30. Diarrhoea also affected the men in casemates more than those ia barracks, in the proportion of 104 to 74. Many case- mates no longer occupied by troops are used as quarters for married sol- diers ; and their children, living under such conditions, are notably wan, sickly, rachitic and tuberculous. In the original construction of casemates in our service, brick arches were covered with sheet lead and the intervening valleys filled with earth. A thin layer of concrete with brick pavement completed the roofing. The weight of this roofing, in course of time, has in nearly all instances forced the underlying hard parts through the sheet lead, thus giving rise to leaks which are frequently of large size. At Fort Trumbull, in 1895, examina- FiG. 204.— Improved Plan ol Construction for Casemates. tion of casemates unoccupied for some time disclosed water standing under the floors at a. level of ten inches. The natural dampness of such case- mates predisposes to rust, mould and decay, and fires must be maintained by their occupants, even in the hottest weather, to dry the air. Chilled in winter, casemates retain a low temperature weU into summer. This has been explained by the finding of ice in the depressions Jbetween arches, when imcovered for repairs, well into warm weather. Such conditions re- sult in added dampness of casemates, through the condensation on the waUs of moisture from the entering warm air. Casemates will probably rarely be necessary in future fortifications, ex- cept in such number as would afford sufficient protection during action. Where they are required, a space should be constructed between the inner wall of the casemate and the rampart, as shown in the accompanying illus- tration, and this should be properly supplied with flues to secure ventilation and dryness. The roof of such casemates should be covered with a heavy coat of cement, and possess a considerable slant to better turn aside the water which percolates through the earth. The future use of sheet lead, as a roofing material, should obviously be avoided. 432 THEORY AND PRACTICE OF MILITARY HYGIENE. Casemates are totally unsuited for the shelter of troops and should never be employed for this purpose, unless temporarily in time of war. Modern barracks and quarters should be constructed outside the permanent forti- fications, but in their vicinity, and should preferably be made of wood to facilitate their futiu'e destruction if this at any time be required for military reasons. The quartering of troops in casemates during time of peace can- not be justified in any manner. Guard Houses. — Of all the buildings at our military posts, the guard houses are th^se which call forth the greatest number of complaints as to the insufficiency of their accommodation, want of proper ventilation and generally unsanitary condition. So frequent have these criticisms been, of recent years, that it would almost seem as if the authorities had tacitly regarded rmhygienic surroundings as part of the penalty to be incmred for military offenses — apparently not taking into consideration the fact that, where guard houses are bad, guard duty itself, for those detailed for its per- formance, practically becomes an undeserved punishment. As far as the prisoners are concerned, also, even though confinement results from the voluntary commission of offenses entailing a known penalty, the Govern- ment possesses no moral right to jeopardize health through the withhold- ing of proper sanitary smroundings. The plainest fare, the hardest bed and most rigid confinement should in no way interfere with the strict observance of hygienic detail in the arrangement and management of the prison and care of the prisoners. Eecently this fact appears to have been more fully appreciated, and an earnest effort is being made to bv^tter the prison facilities throughout our service. Many guard houses have lately been remodeled and new ones built. In the construction of guard houses, the same general principles apply which govern the construction of barracks. In some respects these are even more important — from the restricted life led by the prisoners ; the arduous and often uncleanly nature of their duties ; their frequent lack of soldierly interest with respect to the care of their persons and surround- ings ; and finally, the fact that all the inmates are constantly present at night, and no deductions can be made — as is the case with barracks — for absence on military duties. An abundance of floor and air. space must be provided. Small cell-rooms should never be constructed, but all cells should be in the form of iron cages, in large well-lighted and well-aired rooms, with a free passage-way on all sides. Where the old system of small individual cells with solid walls is in use, it should not be forgotten that greater floor and air space must be provided for each man than would be required for general squad-rooms. Usually the ventilation in cells of this character is very defective, and measures should be taken to remodel guard houses having this system of confinement in operation — particularly since the use of night-buckets is generally required of prisoners. Where it is contemplated that prisoners should eat their meals in the guard house, a separate mess-room should be provided. There should be ample latrine and lavatory facilities, and these should be located in an addition having three sides exposed to sun and air. The great frequency with which guard houses become infested with vermin render the employment of imperme- able walls and floors a sanitary necessity. , Quarters. — Tbe quarters of officers will usually be found of good char- POSTS, BARRACKS, QUARTERS AND HOSPTIALS. 433 acter and well cared for. They are ordinarily nrnch better constructed than barracks, and are generally comfortable. To this, however, there are some exceptions. Officers' quarters, under present conditions, can rarely be overcrowded, and hence neither size nor ventiLating facilities re- quire serious attention. The most grave defect ia quarters of this charac- ter is the general absence of bath-rooms and water-closets — a fault which has fortxmately been remedied in most of the buildings lately erected for this purpose. The controlling authorities have long insisted upon the erection of officers' quarters in double sets under one roof. This saves the cost of one gable wall and makes the houses somewhat warmer, but to offset this, one half of these quarters never receives its full share of sun- light and is often cut off from prevailing winds. Single sets of quarters, with free exposure on all sides, are much to be desired ; and in the mili- tary service the slight increase of land required for such improvement cannot be a consideration. The quarters occupied by manied soldiers and their families, at the larger proportion of our posts, are usually poorly constructed, worse kept in repair and much over-crowded. Usually of too limited number and capacity to accommodate the considerable number of families requiring shelter, at a number of stations the complaisance of commanding officers has resulted in the erection of flimsy and unsanitary structures, often in con- siderable numbers, built by the men from such waste lumber, refuse canvas and old tin as could be obtained. Such quarters are offenses against not only the sanitary condition but the appearance of a post. To permit their occupancy is to do iajmy to the health of their inmates and to maintain foci from which disease, favored by their unsanitary character, may readily spread to troops in barracks. As long as buildings of this kind exist, they will usually be occupied and afford an excuse for the presence at the post of unauthorized camp followers, often of an undesirable character. Such buildings should be destroyed at all stations throughout our army, and the erection of any structures of similar nature forbidden in the future. At all posts there should be sufficient quarters of good character, provided by the Grovernment, to furnish accommodations to a fixed percentage of mar- ried soldiers, based upon the maximum strength of the garrison. This percentage should apply throughout the army, so that on the changing of station by troops the number of families of soldiers who possess a legal status may be sure of proper habitations wherever they may be. In france, quarters are provided for four married soldiers ia each regiment. This allowance is obviously quite insufficient for our service. From the constant communication between the barracks and the quar- ters of married soldiers, it is evident that unsanitary conditions iu the lat- ter will not be without unfavorable influence on the health of the troops generally. There should, therefore, be careful hygienic supervision over them. It would be of great advantage if each company commander were required weekly to inspect the quarters and premises occupied by the civilians attached to his command — the same as he inspects his company barrack — and be held accountable for the proper condition of the same. Hospitals. — All that has been said with respect to site, surroundings, general method of construction and care of barracks applies with even greater force to hospitals. In posts, the hospital should be located weU 28 434 THEORY ANT) PRACTICE OF MILITARY HYGIENE. away from other buildings, but at the same time should be within reason- able distance of the troops whose needs it is to serve. General hospitals should be at central points possessing numerous line^ of communication. They should not adjoin posts or garrisons, to prevent possible attempts at interference with their administration on the part of commanding officers of the latter. Military hospitals are conveniently grouped into those of a permanent and those of a more or less temporary character; the latter in our service being divided into frame pavilion and tent hospitals. In many foreign armies, especially where the number of troops stationed in a town is not large, certain portioiis or wards of civil hospitals are devoted to military use ; the soldiers admitted to them being exclusively under the treatment of military medical officers. This practice has not been em- ployed in the United States service. In time of war, when the capacity of military hospitals is temporarily exceeded, sick soldiers are often trans- ferred to civil hospitals for treatment ; but under such circumstances they are placed entirely imder the control of the medical staff of these iasti- tutions. In every hospital, of whatever size, there must be a portion devoted to administration purposes, general and isolation wards and their accessory rooms, operation-room, dispensary, laboratory, mortuary, mess-hall and kitchen. In large hospitals there should also be a laundry. The precise disposition of these essential parts of a hospital depends upon the size of the institution and the fimds available for its establishment. Where possible, separation of the wards and administration building should be aimed at ; also separation of the wards from each other and from all accessory de- partments. However desirable it may be, complete separation of the ■ operating-room in small post hospitals is not practicable under present conditions. In the military service, as opposed to civil life, the shape and area of the hospital site will rarely require consideration in the arrange- ment of the institution. In foreign armies, hospitals have until quite recently been large, solid buildings of many stories; all the portions, accessory as well as essential, being within the same walls and in close relation to each other. In our own service, the small number of troops located at any one point has made our hospital buildings of correspondingly small size. Considerations of economy, moreover, have forced the building of hospitals of the above undesirable type and have also led to various defects in construction — no single building at a military post, without special legislative authority, being allowed to cost more than twenty thousand dollars. This require- ment obviously imposes serious restrictions upon internal arrangement and construction, and prevents the adoption of a nxunber of needed reforms. In the ordinary plan of post hospital, of comparatively recent adoption, the cost of construction is usually at the rate of about six himdred dollars per bed ; but in the new hospital at Fort Leavenworth the expense per bed is double that amormt. In the old frame wooden hospitals, as existing at most of the western stations, the cost of construction is about three hundred dollars per patient. From the financial necessity of building post hospitals of a compact nature they naturally and unavoidably present very many defects, of which the accompanying plans of the new hospital at Fort Snelling furnish excel- POSTS, BAEEACKS, QUAETEES AND HOSPITALS. 435 lent illustrations. Among these faults may be mentioned the crowding together and close connection of the administrative portion, wards, kitchen 436 THEOEY AND PRACTICE OF MILITAEY HYGIENE. and lavatories, which should all be separated from one another. The lava- tories especially should be outside of the main builduig; yet not only are they placed in this building but are located adjoining the mess-room, a single wall merely intervening between these rooms and the water-closets. The room intended for purposes of isolation is in no sense isolated, and can be reached only through the main portion of the hospital. It should be entirely walled off from the main portion, if it must be retained in the hospital building proper, and should be reached from the outside by a separate stairway. It should have a room for attendants adjoining it, and should also be provided with entirely separate water-closets and lavatory facilities. It should be ventilated separately. The ofi&ce facilities in post hospitals of this character are also insufficient. In those built on the new plans, the upper floor, under the mansard roof, is usually left un- finished. In some instances the needs of the service have required the use of this floor ; but the ceiling is much too low for its satisfactory use for the shelter of the sick, so that the rooms gained by finishing off this floor are extremely hot in summer and not well ventilated. They should not be employed for other than storage or for dormitories for men of the hospital corps. Whenever the probable need of using this upper floor in the future is at all apparent, the wall should be built two feet higher than in present plans, and the whole hospital building should have a double roof. This need not greatly add to the cost and would conduce greatly to comfort. The kitchens in the new post hospitals are also too small to meet the needs of any great number of sick, whUe their location does much to raise the temperature of the main building unduly during hot weather. The storage facilities provided are insufficient, and the present arrangement of a mortuary in. the basement is highly undesirable. In spite of these defects, which appear to be largely unavoidable from financial reasons, our later pattern post hospitals compare favorably in character, so far as they go, with similar institutions abroad. In hospital construction, the determination of the material best adapted for wall surfaces is one of the most difficult problems. An impervious surface is essential. Soap-stone finish has been much used to meet this need and is fairly satisfactory. Square corners should not be allowed, nor should any mouldings or recesses be permitted. The amount of wood-work around windows should be reduced to the minimum. In many civil hos- pitals the window sashes are made of iron. The floors should be well laid, solid, and free from cracks, and should be rendered impermeable with paraffine. In operating-rooms, lavatories and water-closets the flooring should be of terrazzo. Only two rows of beds should be permitted in a ward, and in many hospitals a window is located between each bed. No bed shordd be nearer to its neighbor than five feet ; thus giving eight feet of wall space per capita. Notter and Firth recommend the provision of one square foot of window space to each 80 cubic feet of space in the ward. As regards the internal equipment of wards in post hospitals, it should be accepted that nothing should be allowed for this purpose which is ab- sorbent or cannot be readily disinfected. Bedsteads should be of iron throughout, and be coated with white enamel paint. Bedside and dressing tables should be of enamelled iron with smooth tops of heavy glass. The POSTS, BAERACKS, QUAETEES AND HOSPITALS. 437 wooden tables still in use in some of our hospitals should be abolished, and the same also appHes to wooden chairs. Where such are still kept in use they should be well varnished at least twice a year. Excellent chairs 438 THEORY AND PEACTICE OF MILITARY HYGIENE. of enamelled iron are now manufactured for ward use, and these should be supplied throughout our service. One chair to each three beds will usually be sufficient. Curtains and bed canopies, still in use in some foreign mili- tary hospitals, are of course totally unfit for use in buildings where the sick are cared for. Colored bedspreads should not be allowed ; those used should be of white material and be frequently washed. The wooden bed-screens covered with hollands, ia use in some of the older hospitals, should be abandoned. The frames of such screens should be of enamelled kon, and these should be covered with ordinary sheets, maintained in a state of absolute cleanliness. The wooden bed-trays, stUl in use, should be re- placed by those of light enamelled metal. Floors should be wiped daily with damp cloths moistened in a solution of mercuric chloride. The cocoa- fibre matting, used until recently, has wisely been discarded. The rubber matting now issued in its place should be wiped down with the solution at the same time as the floor. It should be frequently moved from its place for cleaning, since dust collects beneath it. Walls should be wiped down with a disinfecting solution at least once a month. If the number of sick permits, the wards of a hospital should be used alternately, chang- ing every month. The ward so vacated, with its contents, should be disinfected with formaldehyde and then aired for several days after the removal of the patients. The disinfection of operating-rooms with for- maldehyde, after each operation on a case presenting septic conditions, is indicated. All patients should, if possible, be bathed before being ad- mitted to a ward. Their clothing should be taken from them and diski- fected before being stored away, and their underclothing should be washed at once. Pajamas or night-shirts, according to the case, should be sup- plied from the hospital equipment. All bed-linen should be changed twice weekly, and oftener if soiled. Blankets, bed-spreads and mattresses should be frequently sunned. In time of war, the ordinary hospital accommodations of an army in the field are quite insufficient to meet the demands upon them ; and many of the hospitals in garrisons, scattered throughout the country, will not be available for use. Many sick and wounded wiH be treated in movable field hospitals, but a large proportion of the more serious cases, not immediately fatal, will ultimately reach the more permanent establishments required in base or general hospitals. All modern sanitarians agree that where large numbers of the sick must be treated, the use of independent pavilion wards is far preferable. In civil life, large massive hospital buildings are giving way to small detached sections, and in the military service the ad- vantages of the latter arrangement are even greater. Such buildings are cheap and readily put up. Eegarding the pavilion as the unit of hospital construction, any enlargement of accommodation is readily accomplished by the addition of such number of pavilions as may be required. If these become old or infected they may be readily burned without great expense ; and in certain civil hospitals in this country it is contemplated that the wooden pavilion isolation wards shall be destroyed by fire every ten years. Pavilions are open on aU sides to air and sunlight ; and being comparative- ly small, the danger of any extensive epidemic occurring in a hospital is averted. They are particularly adapted to the shelter of convalescents and wounded, since there are no stairs to interfere with entrance and egress. POSTS, BARRACKS, QUARTERS AND HOSPITALS. 439 When properly laid out, a hospital composed of such wards is easy of ad- ministration. All the main bmldings should be reached by covered pas- sages, open at all sides, for the protection of the hospital staff and convalescents during hot or stormy weather. The general arrangement of pavilion hospitals varies greatly. During the Civil War a number of different ground-plans were devised; but, in many of these, sightliness and convenience of administration apparently Fig. 207.— United States 4rmy General Hospital, Fort Monroe, Virginia. 1, Wards; 2, administration building ; 3, oflBoers' quarters and"mess ; 4, guard bouse ; 5, commanding officer's quarters ; 6, operat- ing-room; 7, female nurses' quarters; 8, laundry; 9, pump-house ; 10, cbapel; 11, dead-bouse; 13, store-bouse ; 13, stables. Tbe unnumbered buildings in the enclosed space are mess-balls. received more consideration than did sanitary matters. At present there are three arrangements which are commonly used in our own and foreign armies. These consist in locating the wards on the outer side of a covered way, shaped like an inverted letter V ; in establishing them on two sides of a central square ; and in arranging them in two parallel lines on each side of a central covered passage-way. The general hospital at Fort Monroe is buUt in the form of an inverted V; similar to the plans of the Lincoln and McClellan hospitals as used during the Civil War, and the hospitals used by the French at Metz in 440 THEORY AND PRACTICE OF MILITARY HYGIENE. 1870-71. The administration portion of the hospital is located between the two converging covered ways ; the wards standing obliquely away from the latter in such a manner as to receive the full benefit of wind and sun - 1 0) 1 1 u 7' " m 1 Fig. 208.— Plan of United States Army General Hospital at Savannah, Georgia. 1, Wards ; 3, nurses' quarters ; 3, commanding officer's quarters ; i, administration building ; 5, store-house ; 6, officers' quarters ; 7, officers' mess ; 8, chapel ; 9, guard-house ; 10, dead-house ; 11, hospital corps dormitory ; 18, mess-hall, hospital corps ; 13, mess-hall and kitchen for patients ; M, dispensary and store-house ; 15, operating- room and ward ; 16, library ; 17, officers' club ; 18, bakery ; 19, engine-house ; 20, ambulance stable ; 21, fuel shed ; f ~ POSTS, BAERACKS, QUARTERS AND HOSPITALS. 441 without interference with each other. The wards are all properly oriented, in this arrangement, and there is no crowding. There are seventeen pavil- ion wards, which are expected together to accommodate one thousand pa- tients. The buildings are of rough construction and were originally roofed with tarred paper. Later they were shingled. The chief disadvantages of this hospital are difficulty of administration and a too great size of the individual wards. The general hospital at Savannah, also having a capacity of one thou- sand beds, is well planned and arranged for purposes of administration ; the wards being set at right angles from, and close to, a long central corri- dor. The long axes of the pavilions, however, run north and south, which is quite undesirable in hospital buildings in such a southern latitude. The buildings are also too much crowded together, and seriously interfere with each other in respect to air currents. The space covered by the hospital pavilions allows but 360 square feet per bed, and the wards are located but 35 feet apart. This gives much too small a ground area. Great import- ance is attached by all sanitarians to an abundance of free air space about hospital buildings ; and, as illustrating this point, Stevenson and Murphy give the following figures with reference to the size of the hospital site, as compared with the number of patients, in a number of the best modem hospitals. Approximate area of site, (jtEBMANT. . per bed, in square leet. Priedrichshain 1,713 Tempelhof (military) 1,308 Moabit 1,144 University, Halle 1,575 University, Heidelberg 1,070 France. Bourges (military) 1,600 St. Eloi 1,615 St. Denis 1,685 Belgittm. Antwerp 1,126 United States. Johns Hopkins 1,679 Mouat recommends a zone of aeration about each hospital building at least double its height, and modern practice tends to go even beyond this Mmit. In the military service, where the cost of land is generally not a consider- ation, the slightly increased facility of administration gained by bringing buildings closely together by no means counterbalances the sanitary dis- advantages of overcrowding. The general hospital at San Francisco, with accommodations for 600 patients, occupies a space 662 by 594 feet and provides a hospital site of 660 square feet to each patient. There are ten general wards. Each ward has an inside length of 153 feet; and, including lavatory and admin- istration rooms, of 180 feet. ' The width of each ward proper is 25 feet; the space between them 35 feet. These buildings are located in parallel lines on each side of a central square, in which are the operating-room and mess-haUs. This square is partially closed in at one end by the adminis- 442 THEOEY AND PEACTICE OF MILITAEY HYGIENE. tration building. It is bordered by a covered passage connecting aU the wards, and also bisecting the central square. The plan of this hospital is very similar to that of the Lariboisifere, in Paris. It is very convenient, weU. planned and easily administered, and probably represents the best type of arrangement for pavilion hospitals. Pavilion wards, in civil communities, are built in a number of forms. For the military service that of a simple parallelogram is employed ; the hos- pital complete costing at the rate of about one hundred dollars per patient. The interior arrangement of these wards varies slightly in our service, but the plan as used for the pavilions in the general hospital at Savannah may REFERENCE A AdtnJnUliaUDD Pa.llii E FomBle.NDnaj' LtaloTTurscs' D Wtra E OpersUoD F DinlDE ud Offlc G "Kltchon .^ Det&llnl Mens' J VorandB It QuBttnTQin.L.r'a Storohonie L Lauodiy BulldSng Fig. 209.— Plan ol the United States Army General Hospital at the Presidio, San Francisco, California. be considered a& fairly representative of all. This pavilion ward is a frame wooden structure, with double doors at each end and at the centre of each side. It is weather-boarded outside and wainscoted inside. The portion occupied by patients is 92 feet long and 23 feet broad, contains 40 beds and allows 53 square feet per man. The height is 10^ feet, and the cubic air space per patient is 556 cubic feet. In addition to the ward, within the same walls there are nurses and ward-masters' rooms, lavatories and bath-rooms, water-closets and store-rooms. These pavilions present a number of serious disadvantages from a sanitary standpoint. The floor space per patient should be more than twice as much as is actually pro- vided. In the British military hospitals, 100 feet of superficies is allowed to each patient, and Notter and Pirth regard 120 square feet per bed as the minimum for hospitals. Some of this space may be gained by widening the present pavilion building by two or three feet. The cubic air space provided POSTS, BAKEACKS, QUAETEES AND HOSPITALS. 443 IZZl o IZZI per bed is also much too low ; being 44 cubic feet less than the amount the healthy British soldier is entitled to receive in barracks, and but 46 per cent, of what is officially allowed (1,200 cubic feet) to each patient ia hospital ia the same service. Notter and Firth place the amoimt of air space which should be provided in general hospitals at 2,000 cubic feet per bed, or nearly four times the amount furnished by our pavUion wards. That serious results have not followed this deficiency in ak space is due to the fact that these hospitals have never been filled to their fullest capacity, and are also located ia climates in which the windows and doors may be kept open a large portion of the time. The height of these pavilions should be increased to 12 feet. The beds are also too crowded, having an allowance of but 5 feet 7 inches of running wall-space, where all authorities demand 7^ to 8 feet per bed as a minimum. The windows should be made larger, and be carried ^p higher toward the ceiling. Rooms for nurses and ward- masters attached to a large general ward are quite unnecessary. Nurses should not be allowed to sleep in close proximity to the sick, and when attendants who have been on duty during the day are relieved they should leave the pavilion entirely. The wards themselves, with accommodations for forty patients, are too large. Not more than . twenty-four sick should be brought together in any one ward ; and in the newer ci^dl hos- pitals, the wards are usually intended to hold about sixteen sick. It is distinctly an ele- ment of danger to the individual patient if he is one of a large number of diseased per- sons brought together within the same four walls. The water-closets, bath-room and la- vatory should be placed in an annex at the rear of the ward, separated by a roofed and latticed lobby, so that odors cannot pene- trate into the ward. There should be the most complete severance of atmospheric communication between the annex and the main building; the latter thus containing merely the main ward and two small store- rooms at the end toward the lavatory. There should be no plumbing in the ward building. Wainscoting should not be used, as readily becoming infected. If the build- > &l CZ] nzi [ZZl \ZZi 444 THEORY AJSTD PEACTICE OF MiLITAEY HYGIENE, ings are too light in structure to allow the use of plaster, some one of the many composition boards now on the market should be used in large panels for the inside finish, and thoroughly gone over with shellac. An open fire-place at each end of the ward, to replace two of the heating stoves at present used, would add much to cheerfulness and greatly improve ven- tilation. The latter is a -matter which deserves the greatest consideration, and which is by no means suf&dently provided for in these pavilion wards. The floor space required depends largely upon the means of ven- tilation adopted ; and, with us, both are at present inadequate. For hos- pitals, nothing is more certain than that an abimdance of fresh air must be provided. During the Civil War it was found that wounded treated in tents or loosely-built huts, through which the air freely passed, had little septic disease; while in permanent hospitals, or houses temporarily con- verted for the purpose, the so-called hospital diseases were of frequent occur- rence. Since a hospital is a building which is perpetually producing withia itself the elements of danger to its own inmates, it should be fully under- stood that the roughest shelter which admits of a through current of air is better than a permanent structure without adequate means of ventilation. Smith and Young, in emphasizing the fact that cubic space is of little value imless it is accompanied by ample means of ventilation, give an instance of the Franco-Prussian War ia which it happened that, at about the same time, a church and a slaughter-house in Paris were turned into wards for wounded soldiers. Among the wounded ia the church, gangrene broke out and the mortality was very heavy ; in the slaughter-house no septic disease appeared, and the men made good recoveries. This happened in spite of the fact that the cubic space per man in the church was greater than in the slaughter-house ; but the latter was a mere shed with sides of louvred boards, and the men were practically in the open air, while in the church the wall was solid and the openings were small and few. The necessity for an almost unlimited supply of air governs hospital construction. Occupancy of New Buildings. — To fix the time when barracks or other permanent buildings of recent construction may be safely occupied, the climate, exposure, nature of material employed and manner of con- struction must be considered, since all have relation to the question of dampness. During the erection of a building the materials of construction absorb much water. Bricks, which readily take up water to the extent of ten to twenty per cent, by weight, part with moisture equally readily. The same, however, is not true with respect to plaster and mortar, which do not readily give up the! moisture they may have absorbed. According to Fliigge, mortar used in building construction contains about 14.8 per cent, of water by weight, and 26 per cent, by volume. Plaster absorbs 50.9 per cent, of its volume of water; and the same author states that ia ordinary masonry walls, water is present in the proportion of 13 to 23 per cent, by volume. Pettenkofer calculated that in the masonry of a typical house bunt of 100,000 bricks, there were 10,000 gallons of water which must be removed before the building would become healthful. Since aii' at a high temperature takes up a much greater proportion of moisture, he showed that the necessary drying could be accomplished in about one- twentieth of the time if the building were well ventilated and heated. POSTS, BAERACKS, QUAETEES AND HOSPITALS. 445 From these facts it can readily be understood why a barrack occcupied immediately after completion, and without waiting for the walls properly to dry, should be cold, damp and dangerous to health. For this reason, fires should be maintained ia as many rooms as possible, and drying air currents thus established throughout the building, as soon as plastering is com- pleted. It is a difficult matter to determine the minimum time in which a newly-erected buildiag becomes properly habitable. If the walls are stOl damp they are cold to the touch, and on percussion a dull note is given off quite different from the clear resonance given by a dry wall. Undoubtedly the best method of determiniag the dampness in new walls, and hence the propriety of occupation, consists in detaching fragments of plaster, which should be weighed, dried at 110° C. and weighed anew. Laveran states that ordinary wall plaster should not contain more than 20 to 22 per cent, of moisture. As long as this proportion is exceeded the building should not be occupied. CHAPTER X. VENTILATION. The term ventilation appears to be not infrequently confused, in the minds of line officers, with aeration. In simple aeration of a squad-room the air is changed but once or at intervals, whereas in true ventilation the air is constantly renewed by the passing out of a portion of the enclosed air and the entrance of a fresh supply to take its place. Eegarded, there- fore, as the continuous and more or less systematic renewal of air in a room or other enclosed space, the term ventilation may be strictly defined as the removal or dilution, by a supply of pure air, of the pulmonary ex- halations of soldiers, the effluvia which proceed from their persons and clothing, and the products of combustion from lights and fires. Involving, as it does, the introduction and diffusion of pure external air in continu- ous currents, and the constant removal of a corresponding volume of air more or less fouled by gases, vapors, moisture and particulate matter, or which is warmed above the degree consistent with comfort and health, the subject of ventilation is clearly one of some complexity, and for the mili- tary service is closely connected with the production and distribution of heat. It should be understoq^ that the fresh air introduced in ventilation is not necessarily cold air ; in fact the practical success of the system will, in many capes, depend upon the entering air being warmed. The theory of ventilation depends on a few well-known physical laws, simple in themselves but often somewhat difficult of practical application — so that unsatisfactory results even with apparently good methods are not rarely obtained by the inexperienced. While these physical laws are capa- ble of general application, the local conditions met with are so variable that the ventilation of each barrack building and squad-room must properly be considered as a separate problem. Undoubtedly the most exact method of ventilation depends upon the propulsion, by mechanical means, of a definite amount of air during a given period ; but the expense of installing and operating the necessary apparatus, and more especially the constant attention which it must receive, create serious objections to the use of this method in the military service. Eeliance is therefore to be had upon the ventilation brought about by the diffusion of gases, the inequality in the weights of cool external and warm internal air, and by the movements of external air currents. While perfect ventilation would ensure that none inhaled air which had previously been respired by the man himself or by another, it is obvious that such conditions are not attainable. in barracks; and that all which can be expected is the maintenance of the contained air in a state of relative purity, and within the limits fixed by sanitarians as denoting an amount of vitiation in excess of which the systems of those exposed to its influences may be expected to suffer. VENTILATION. 447 Influence of Ventilation upon Health. — In the military service, the injury inflicted upon troops by requiring them to breathe air contami- nated with respiratory impurities and deficient in oxygen is usually not per- ceptible until after a considerable period of time, and is then often at- tributed to other causes. Though operating in this insidious manner, the evil results of deficient ventilation are none the less positive — as is well shown by comparison of statistics for bodies of men living in ventilated and unventilated habitations, and by the diminution in the rates for sick- ness and death, in foreign armies as well as our own, which in the past has followed improvement in the ventilation of barracks. When moderately vitiated air is breathed continuously for considerable periods, even if. it does not necessarily by itself originate disease, it cer- tainly lowers the powers of vital resistance and thus predisposes to sick- ness. Under such circumstances the individual becomes pale and partially loses his appetite, and after a time declines in muscular strength and mental spirits. The oxygenation and nutrition of the blood appear to be interfered with, and a condition of anaemia is often noticeable. Where the air is rendered extremely impure by respiration, it is commonly rapidly fatal to those required to breathe it. Instances of this promptly fatal effect of highly vitiated air are seen iu the well-known cases of the " Black Hole of Calcutta," when 123 out of 146 Europeans, held as prisoners by the Mutineers, died in the space of about twelve hours ; and of the close prison in which 260 out of 300 Austrian prisoners of war, confined after the battle of Solferino, died in a short time. The poisonous agencies which probably bring about this sequence of events appear to be a deficiency of oxygen coupled with an excess of carbon dioxide, though the symptoms are not those of pure asphyxia. If the persons survive, a febrile condition is usually left behind which lasts three or four days and is often followed by boils and other evidences of affected nutrition. The former great prevalence of pulmonary tuberculosis, iu nearly all European armies, was considered by the commission appointed to investi- gate the sanitary condition of the British army to be chiefly dependent upon the lack of proper ventilation of barracks. Notter and Firth state that while a great amount of phthisis has occurred at all the stations of the British army, even those with the best climates, "there has been of late years a most decided decliue of phthisical cases in these stations, while the only circumstance which has notably changed iu the same time has been the condition of the aii-." Not only may phthisis be considered to have one of its chief predisposing causes in the breathing of an atmosphere deficient in oxygen and highly contaminated by respiration, but other throat and lung diseases — as bronchitis, pneumonia and tonsillitis — appear also to be much more common under such circumstances. As an instance, the medical officer at Fort Douglas, in 1898, reported an imimediate de- crease in the number of cases of tonsillitis among the troops at that post, on installing suitable arrangements in the previously improperly ventilated barracks. There is no doubt, also, but that the constant breathing of a confined and vitiated air, in addition to the production of an impaired state of health which renders invasion by any infectious disease especially liable to occur, particularly favors the spread of the exanthematous fevers. So well are the above facts recognized that the best authorities now insist 448 THEORY AND PEACTICE OF MILITARY HYGIENE. that, if a choice be required to be made between the two, warmth must be sacrificed to some extent in order to obtain a proper amount of fresh air. The influence of pure and impure air on health and mortality is even better shown in the case of horses than among men, since in the first instance the problem is much simplified by the absolute similarity, ia different periods or places, of the conditions of food, water, exercise and treatment. It is therefore of interest to note that in the French army the mortality among cavalry horses, in times past, was enormous — Eos- signol stating that prior to 1836 the mortality of the public animals in that service varied from 180 to 197 per thousand annually. The enlarge- ment of the stables, with the provision of an increased amount of fresh air, has reduced the loss at the present day to 24.2 per thousand. The necessity for free ventilation is greater in hospitals than in bar- racks. The air of a sick ward, unless properly renewed, is well known to be most unfavorable to health ; and by deficient ventilation of hospitals the severity of many diseases is increased and convalescence is greatly retarded. This appears to be true of all diseases, but especially so of the febrile af- fections. Hospital wards, also, are occupied all the time; deficiency in respect to fresh air operating continuously, and not, as is the case with healthy soldiers in barracks, for but a portion of the twenty-four hours. The benign influence upon health of proper ventilation and an abun- dance of fresh air appears to be manifested in three ways. First — by dilut- ing the noxious products of respiration beyond those limits of concentra- tion within which they exert a known unfavorable influence upon the human organism. Also the supplying of the necessary oxygen without its admixture with impurity. Second — ^the fact that moving bodies of air, usually warmed, are great drying agents, and that barracks wiH not be damp when properly ventilated. Third — the fact that currents of fresh air are of great importance in assisting the destruction of bacterial life by the solar rays. Recent experiments have shown that bacilli exposed to free ah cur- rents and the solar rays were killed in two hours, while those exposed to sunlight but which were shielded from air currents survived much longer. Ventilation in the United States Service. — The conditions in re- spect to ventilation, in the greater number of barracks in our service, must be regarded as unsatisfactory. In the older established garrisons, many of the habitations for the men were constructed without proper arrangements for the renewal of air; reliance being apparently had, in many instances, solely upon natural means of ventilation. The necessity for special arrangements and devices to assist the movement of air appears to have been strangely overlooked; and it is true that even as late as 1890 build- ings for the shelter of soldiers were erected without means of artificially renewing the air within them. In one instance, in that year, the defect was so noticeable as to call for special inspection and report — the latter concluding that the attainment of even fair ventilation of the building as constructed would require considerable additional expenditure. From Fort Robinson, in 1895, it was reported that, save in one instance, not a single one of the barracks at that post had any provision for ventilation except windows and doors ; and that these, fi-om the coldness of the cli- mate, must necessarily be kept closed a considerable portion of the year. VENTILATION. 449 In a number of the older barracks, in the construction of which the question of ventilation was not wholly disregarded, or in which an effort was subsequently made to install ventilating arrangements, the matter was often not properly approached. Particularly was the fact often lost sight of that air will not pass out of a room unless arrangements are provided for its admission in proportionate voliune, and that it wiU not enter unless a corresponding proportion of the contained air be removed. Hence, in our service, even at the present time, sanitary reports show that in many cases outlets have alone been provided — the room, with its doors and windows closed, thus having the character of the ventilation which might be found in an uncorked bottle — while in other cases sufficient provision has been made for admitting fresh air, but no means of es- cape arranged for that which is vitiated. It is true that where such a single opening is provided, double currents, moving inward and outward, are established ; but under such circumstances friction is great unless the opening be very large, and the currents are always feeble and may so oppose each other as even to prevent all movement. Special aper- tures for the entrance and egress of air should therefore be provided; and it may here be remarked that the practical necessity for this is shown by a very simple experiment (Fig. 211). If a lighted candle be placed in an open wide- mouth bottle the flame is soon extinguished. If the air be renewed, the candle again lighted and the mouth of the jar "Fl^riiT be closed by a stopper pierced with two holes, each contain- ing a glass tube, but of imequal length, the flame continues to bum brightly. The partial closure of one of these tubes, B, causes the flame to diminish in size ; and on the complete closure of the tube it dies out. In some of our barracks, intended outlets have been cut through into lofts and garrets, while these spaces have not been provided with ventilating shafts leading into the open air. Under such conditions it is obvious that there is no ventilation. Even in some of our barracks of latest construc- tion, provided with ventilating flues, properly located and of sufficient size, these have been made, by some strange oversight, to discharge directly into the loft under the roof. It is true that outlets for this space were also provided — but the undesirability of converting the highest space in an inhabited building into a mixing reservoir for foul air and the dust which it carries, often of an infectious nature, should certainly be apparent to aU ; particularly in view of the fact that the danger is always present of having this foul air and some of the dust carried back into the squad- rooms by reverse currents. It should be an invariable rule that each squad-room should be ventilated separately, yet this has not always been done. In many instances also the openings provided have been entirely insufficient in size for the work which they were expected to perform ; and further, the improper location of such ventilating openings as were pro- vided has not rarely been made in the past. That defects of the above character are so commonly seen furnishes a strong argument for the sub- mission of aU working plans for barracks, before any buUdings are erected on their lines, to the authorities of the Medical Department. The mistake is too frequently made, in our service, of considering that persons with- 29 '450 THEORY AND PRACTICE OP MILITARY HYGIENE. out any special knowledge of sanitation are properly fitted to decide on matters which, like that of ventilation, are purely sanitary. Vitiation of Air. — -In considering the nature and the amount of the impurities added to air by respiration, it is of advantage to contrast the percentage composition of ordinary air with that which has been expired, in respect to their chief constituents. These are as foUows : Ordinary air. Expired air. Oxygen 30.96 16.40 Nitrogen 79.00 79.19 Carbon dioxide 0.04 4.41 From this it will be seen that the expired air contains over one hun- dred times more carbon dioxide, nearly five per cent, less oxygen, and a small amount of nitrogen more than the atmospheric air. Hence during respiration more oxygen is taken into the body from the air than carbon dioxide is given off; so that the volume of the expired air is from one- fortieth to one-fiftieth smaller than the volimae of the air inspired, both being calculated as dry, at the same temperature and pressure. This dim- inution of the volume of the expired air is, however, far more than com- pensated for by the warming which the inspired air undergoes in the re- spiratory passages, so that eventually the volume of the expired air is really one-ninth greater than the air inspired. The relation of the oxygen ab- sorbed to the carbon dioxide given off is as 4.57 : 4.38. This is expressed by the so-called respiratory quotient : An average adult gives out at each respiration 22 cubic inches of air, and, Assuming that he breathes eighteen times a minute, the total quantity of air which passes out of the lungs in the twenty-four horn's is thus 570,240 cubic inches, or 330 cubic feet. If it be further assumed that the expired air contains 4.4 per cent, of carbon dioxide, the average adult at rest evolves 14.52 cubic feet of this gas in the twenty-four hours, or 0.6 of a cubic foot ' per hour. This amount of carbon dioxide wiU be increased by body activity and varies also with the weight of the individual ; it may, in the case of a , man doing hard work, reach 37 cubic feet in the twenty-four hours, im- plying an hourly elimination of carbon dioxide of 1.6 cubic feet. For sol- diers living under the usual conditions found in squad-rooms, the carbon dioxide given off from the lungs is generally accepted as about 0.72 cubic feet per hour. Pettenkofer, whose experiments are perhaps the most trust- worthy, ascertained that a man twenty-eight years of age, weighing 132 pounds, evolved 0.56 of a cubic foot of carbon dioxide per hour at night, during repose, and 0.78 in the day time under very moderate exertion; ; during hard work the same man evolved 1.52 cubic feet per hour. These amounts give the following : In repose. 0.00434cubicfootofCOa evolved per pound Of body -■weight. In gentle exertion. 0.00591 " " " " " " " " " Inhard work.... 0.01152 " " " " " " " " ," These figures, though based upon an individual of considerably less Weight than the average soldier, are nearly in the ratio of 2, 3 and 6 — and VENTILATIOK. 451 this may serve as a guide to the proportions of fresh air required under different conditions. Since ordinary unrespired air contains an average of 0.4 parts of carbon dioxide per 1,000, it is obvious that any excess beyond this amount implies vitiation. In a closed and occupied space a certain amount of impurity must always be present in the air, and it thus becomes important to de- termine the permissible limits of such impurity. This has been fixed by de Chaumont and others at 0.6 parts of carbon dioxide per 1,000, or 0.2 parts in excess of that already present in the atmosphere, and this stand- ard is now accepted by aU sanitarians. It is based upon the observed fact that when the respiratory carbon dioxide exceeds this proportion, the air in the room begins to smeU close and foetid. Having established a standard as to the respiratory impurity which may be regarded as permis- sible, it becomes easy to calculate the amount of fresh air needed properly to dilute the air expired by the soldier during a given time, so that the car- bon dioxide contained in the resulting mixture shall not exceed the per- missible limits. As compared with the standard of respiratory impurity given above, the air of barracks usually shows a high degree of vitiation — less so in the newer and better ventilated buildings. At Fort Eobinson, in 1895, the barracks being unprovided with ventilation faciLLties, the amount of carbon dioxide found in eight squad-rooms ranged from 1.334 to the very high proportion of 2.600 parts per 1,000. In England, a large number of an- alyses of the air in barracks was made by de Chaumont, the amount of carbon dioxide in the external air being simultaneously determined. The cubic air space allowed per man was 600 cubic feet. Typical results obtained by him were as follows : COain external air. COs IN ROOM. Mean respiratory Largest amount found. Mean amount found. impurity in COj In excess of that In external air. 0.430 0.393 0.440 0.470 0.420 0.425 0.422 0.409 0.555 1.846 1.971 1.408 1.175 1.731 1.874 1.027 3.484 2.344 0.645 1.404 0.976 0.718 1.338 1.209 0.838 1.651 1.335 0.215 Anglesey barracks 1 Oil 0.536 Chelsea 0.248 Tower of London 0.898 0.784 Fort Brockhurst (casemate) Aldershot Military Prison, cells.. Gosport Military Prison, cells . . 0.416 1.242 0.780 Published analyses of air of prison cells show, in aU cases, a very high degree of respiratory impurity, and this is probably one of the chief de- pressing influences of long cell confinement. Wilson gives some import- ant information on this point. In cells of 614 cubic feet capacity, always occupied, he found the CO^ to amount to 0.720 per 1,000; the prisoners were healthy and had a good color. In cells of 210 cubic feet capacity, occupied only at night by prisoners employed outside during the day, he found 1.044 per 1,000 of CO, and the occupants were all pale and anaemic. "Wliile exact figures for our own service are lacking on this point, medical 452 THEORY AND PRACTICE OP MILITARY HYGIENE. officers wiU frequently be impressed with the paUor of prisoners housed in poorly ventilated guard houses, especially in the case of such prisoners as are detailed for considerable periods as room-orderUes. In the limita- tion of evO. results upon health through such constant confinement in bad air, it is clear that the inside work of policing should be performed by the prisoners in rotation, and no one man should be allowed continually to do such work, as is not infrequently the case. Outside labor in the open air is, in practice, a privilege and a benefit to prisoners. The amount of respiratory impurity in badly-ventilated barracks, as might be expected, increases with length of occupancy. Hence the period of greatest vitiation in squad-rooms wOl be found shortly before reveille. Leo found the following amounts of carbon dioxide, in a barrack at Alber- stadt, at different hours of the night : Hours. Parts of CO2 per 1000. 8 to 10 0.86 10 to 13 1.57 Hours. Parts of COj per 1000. 12 to 3 3.14 3 to 4 3.48 In spite of its greater specific gravity, there is, in practice, no accumula- tion of carbon dioxide near the floor of an occupied room, since expired air is warmer and hence lighter than the surrounding atmosphere. Le- blanc, Coulier, Pettenkofer and others have shown that carbonic acid is always present in greatest amount at the top of an inhabited space. In a theatre, at the end of a performance, Leblanc found 1.5 parts of 00^ in air samples taken in the orchestra, and 3.0 parts per 1,000 in air taken in the highest gallery. Laterally, carbon dioxide is equally diffused through the air of a room. It is very rapidly got rid of by opening windows, and in this respect differs from organic matter and probably from watery vapor ; neither appearing to diffuse rapidly or equably through a room. With respect to the direct influence of an excess of carbon dioxide upon the organism, the gas is said by Stevenson and Murphy to produce fatal results when the amount reaches from 50 to 100 parts per 1,000 volumes; while at an amount much below this, usually placed at 15 to 20 parts per 1,000, it produces severe headache. Some persons can inhale without in- jury, for a brief period, considerable quantities of pure diluted carbon dioxide ; and animals can be kept for a long time in an atmosphere highly charged with it, provided the amount of oxygen be also increased. With the air of respiration, headache and vertigo are usually produced when the amount of carbon dioxide is not more than 1.5 to 3 volumes per 1,000; but to this result the undue heat of the room, under such circumstances, probably contributes. The presence of a very large amount of carbon dioxide in the air may lessen its elimination from the lungs and thus re- tain the gas in the blood — and in time this may produce serious impair- ment of nutrition. The same principles which govern the calculation of fresh air, needed to dilute and remove respiratory impurities as indicated by the amount of carbon dioxide present, apply also to the case of air vitiated by gas- lights, lamps and candles. Where the products of their combustion are allowed to pass directly into squad-rooms, as is the case in our service, the impurities added wiU be considerable, and fresh air should be supplied to VENTILATION. 453 dilute and remove them. For their proper dilution, however, the amount of fresh air supplied, in relation to the carbon dioxide evolved, need not be as great in their case as for breath impurities, since organic respiratory emanations of deleterious character must be considered iu connection with the latter. It has been calculated that for every cubic foot of coal-gas burned, 500 cubic feet of fresh air must be introduced hourly to dilute the products of combustion properly; and this is not a high estimate when it is considered that a cubic foot of good coal-gas produces one-half a cubic foot of carbon dioxide, together with a certain amount of sulphur dioxide and other substances. The flat flame gas-burners used in our barracks are calculated to consume 6 cubic feet of gas hourly ; and in an evening of four homrs one such burner wiU thus . generate 12 cubic feet of carbon dioxide. Assuming that a supply of 1,000 cubic feet of fresh air is re- quired for every cubic foot of carbon dioxide produced in this manner per hour, it is therefore necessary to supply 12,000 cubic feet of air, during the evening, to each regulation gas-burner — or about 3,000 cubic feet per hour. This amount is about equal to that required for respiratory purposes by a soldier in barracks during the same period. Since for a squad-room containing twenty -four men probably six such gas-burners would be neces- sary, it follows that provision should be made, when gas is burned imder such conditions, for the admission of about one-fourth more fresh air than would be required during daylight. These facts abimdantly demonstrate the great importance of directly removing the products of combustion by a special channel — a method clearly preferable to the present practice of allowing them to contaminate the .air, even if ventilating arrangements capable of providing a greater supply of air, while lights are used, were secured for squad-rooms. Speaking generally, the Welsbach gas-burner uses up only half as much air, the illuminating power being the same, as the ordinary flat six-foot burner. According to Notter and Firth, one pound of mineral oil requires 138 cubic feet of air for complete combustion, and properly to dilute the products of its combustion about 8,000 cubic feet of air are necessary. Since incandescent electric lights contribute no impiiri- ties to the atmosphere their use entails no extra provision of fresh air. This quality is a strong argument for the employment of such a means of lighting. Where barracks are warmed by hot air, hot water or steam, it is obvi- ous that the products of combustion from fuel used in heating wiU not assist in the vitiation of the air of squad-rooms, nor, with the proper dis- tribution of fresh air to such central heating plants, need the quantity of oxygen required in the combustion of fuel be a matter requiring considera- tion from the standpoint of ventilation. But where squad-rooms are directly heated by stoves, as is the case in many of our barracks, the subject at once assumes a practical importance. According to Notter and Firth, for the complete combustion of one pound of coal at least 160 cubic feet of air are required by theory ; but in actual practice from half to twice as much air inust be supplied, making the average amount required per pound of coal to be from 240 to 300 cubic feet. Since so many varieties and sizes of stoves are in use in our service, no general figures as to the amount of fresh air to be supplied to fires in squad-rooms can be given, but knowing the average consumption of coal in any given instance the amount 454 THEOEY AND PEACTICE OF MILITARY HYGIENE. of fresh air properly to be supplied for purposes of combustion can readily be calculated. During the burning of coal about one per cent, is given off into the air as soot and tarry products, with large quantities of carbon dioxide and carbon monoxide. Where stoves are ia sound condition, and are proper- aUy cared for, these impurities should not escape into the room, but should pass out through the chimney into the external atmosphere. In practice, however, these theoretical conditions will frequently not be obtained in barracks. Improperly jointed stove-pipes or stoves which are cracked and broken are not rarely seen, and through the fissures and crevices of such defective appliances the impurities of combustion may escape into the room in considerable quantities. In some forms of stove used in our service, spaces in the doors are closed with sheets of mica. These are often knocked out by careless handling, and their prompt replacement does not seem to be regarded as important by most company officers or quarter- masters. Deficiencies of this sort may contribute largely to the atmos- pheric impurities in the room. In the care of fires, also, the average room-orderly uses little discretion. In very cold weather especially the fires will be maintained at their maximum, and a red-hot stove is consid- ered rather as desirable than otherwise by most soldiers. It has long been recognised, however, that where this overheated condition is present much carbon monoxide may pass through the red-hot iron into the air of the room, this gas being far more dangerous than carbon dioxide. Open fires and grates will rarely be used in our barracks, though they are much employed in foreign services. Fires of this sort are particularly subject to down-drafts, generally due to the amount of air required by the fire being less than that which can, during the same period, pass through the normal inlets in a closed room, whereby a certain amount of fresh cold air endeavors to force an entrance down the chimney. This results in the carrying of much smoke and other products of combustion back into the room. The remedy of course consists in increasing the size of the inlet, which may temporarily be accomplished by partially opening a door or window. Serious faults of this character could never occur in properly ventilated barracks. From the above it is obvious that while destroying considerable air for the sake of its oxygen, and requiring a special supply to support combus- tion, certain arrangements for heating may give off, in the air of rooms, when badly constructed or managed, considerable amounts of impurities. The quantity of these impurities is of course very variable. While the chief need of fresh air is usually emphasized with special reference to the removal or dilution of organic or inorganic , impurities, fresh air also plays an important part in the removal of excessive moisture. Watery vapor is given off into the air not only in respiration but also largely by artificial lights ; and not a Little of the discomfort attending vitiated atmospheres is due to the large amount of their contained moisture. Expired air is practically of the same temperature as the' body, and is saturated with water vapor. Consequently any volimie of air much vitiated by respiration soon becomes heated air and more or less saturated with moisture. But air which is loaded with moisture transmits, in each unit of time, much more heat than aix which is dry. Hence, when air at a VENTILATION. 455 high temperature is saturated with moisture it commxmicates heat to the, body, producing an oppressive sensation; when the temperature of thei saturated air is lower than the temperature of the body the transfer of heat is the other way, producing a sensation of cold. A low temperature with a dry atmosphere is therefore more comfortable than a higher temperature when the air is loaded with moisture, for no other reason than that it favors the prompt and regular removal of body -heat by combined conduc- tion and evaporation. Both de Chaumont and Billings have laid special stress on the importance of humidity in connection with ventilation. The former states that an increase in humidity of one per cent, has as much^ influence on the condition of an occupied space, when judged of by the sense of smeU, as a rise of 4.18° F. The amount of water given off to the air by respiration of course varies with the temperature and condition as to humidity of the inspired air, as well as with the size of, and work' being done by, each individual; but on an average of twenty-four hours, the amount may be taken as being 10 ounces, or 300 giams, for each adult — ^to which must be added some 20 ounces more of moisture given off by the skin. If it be assumed that the average temperature of occupied rooms, is 60° F., this means that enough moisture is hourly given off by the human body, in repose, to saturate 90 cubic feet of air. It is this tendency to become saturated witli moisture from the lungs and skin which makes, the air of crowded rooms so uncomfortable. CarneUey's experiments show that for every part of carbon dioxide found in the air, 2.7 volumes — or 1.1 part by weight- — of moisture have been given off by each person inhabiting the room. The removal of excessive moisture by a supply of fresh air is thus important. As is fully appreciated by all officers, poorly ventilated barracks have a distinctive odor of their own, especially strong during the sleeping hours before reveUle or on damp days. This odor, markedly perceptible on pass- ing from the outer air into a crowded, iU.y ventilated squad-room, is made up in part of volatile products of decomposition contained in the expked air of soldiers having decayed teeth, foul mouths or certain disorders of the digestive apparatus, and in part to volatile fatty acids produced from the excretions of the skin, and from clothing soiled with such excretions. To this is usually added the odor of stale tobacco smoke, and also the effluvia given off by the organic matter which is always present on walls and floors. In our newer barracks, from the better means of renewing the air provided of late years, these close, foul odors are much less marked, though they are still very apparent. The direct and indirect effects of such odors upon the comfort and health of soldiers are probably more considerable than are generally ac- cepted. In a fresh, pure air, the inhalations are instinctively full; if the air be vitiated and foul-smell ing the organism is warned through the olfactories and as little air as possible is respired, the oxygenation of the blood being thus interfered with. It is fair to presume that this aversion to the bad odors of vitiated air was intended by nature to serve as a safe- guard against exposure to such influences. In hospitals, from the nature of the conditions often necessarily obtain- ing in them, the production of odors is more rapid and extensive than in barracks. So much organic substance is thrown off in certain diseases 456 THEORY AND PEACTICE OE MILITARY HYGIENE. that scarcely any ventilation is sufficient to remove the odor. In some hospitals, de Chaumont foimd that there was stiU a close smell when 5,000 cubic feet of fresh air, and even more, were supplied to each man hoittly. In general, and without attempting to demand too much, it may fairly be assumed that the quantity of fresh air to be supplied to every room used for the shelter of soldiers should be sufficient to remove aU sensible im- purities. The organic matters contained tu expired air are small in quantity. A certain portion is apparently suspended, and is made up of small par- ticles of epitheliimi and fatty matters derived from the skin and mouth, while another part consists of organic vapor thrown off from the respiratory tract. These organic impurities give rise to the foetid smell abeady men- tioned as being noticed in badly ventilated barracks; and which often hangs about squad-rooms for so long a time, even after the rooms are well aired, as to show that the odoriferous substances are oxidized slowly. Most hygroscopic substances, and particularly blankets and woolen uni- form clothing, absorb and retain these odors with great readiness and tenacity. The organic matters contained in the expired air have been long looked upon as being in the nature of a volatile poison, but recent experiments tend to oppose this view. The conclusions of Haldane and Smith are to the effect that the immediate dangers from breathing air highly vitiated by respiration arise from the excess of carbonic acid and deficiency of oxygen, and not from any special poison; that any hyperpnoea which ensues is due to excess of carbon dioxide and not in the corresponding de- ficiency of oxygen, the hyperpncea usually appearing when the carbon dioxide is present to the extent of from three to four per cent. ; that the frontal headache so commonly produced by vitiated air is due to the excess of carbon dioxide ; that hyperpncea from insufficiency of oxygen begins to be appreciable when the oxygen in the air breathed has fallen to a pro- portion which varies in different individuals. To this must be added the discomfort produced by excessive heat and moisture. With these conclu- sions most sanitarians are now agreed. Drafts, and the Rate of Ventilating Air Currents.— To be sat- isfactory, the renewal of air in barracks should be insensible to the occupants. Cold drafts will not be tolerated by soldiers, and the man who sleeps mader a window or near a ventilator will not permit it to be open to his own discomfort, so that those at a distance may have fresher air. Where the ventilating inlets admit cold drafts, the men, imless carefully watched, wiU invariably plug them up, often with old clothing, gunny-sacks and similar uncleanly articles ; so that in cold weather the condition of the intake apparatus as regards perviousness is thus often an excellent guide to the practical efficiency of its operation. Where ven- tilating inlets are found to be thus stopped up, the sanitary officer need not in all instances at once demand that they be re-opened — in spite of the fact that this action is obviously detrimental to the comfort and perhaps the health of the men — and then consider his duty performed. Under such circumstances, existing arrangements are clearly not satisfactorily accomplishing the purpose for which they were intended, and their practi- cal disadvantages of operation should rather be recognized and efforts VENTILATION. 457 made for their improvement. Often this can be accomplished by screens or other simple means, but in. some instances the faults are so aggravated that some of the existing intakes may have to be wholly or partially closed during cold weather and other arrangements made for the proper renewal of air. Any arrangement for admitting fresh air which is obviously defective should not be permitted to remaiu iudefinitely, as is too often the case in oux service, but should be remodeled at the first op- portunity. In many instances, however, inlets which work satisfactorily under nearly all conditions are temporarily closed by the men during brief periods of windy or severe weather. Under such circumstances the prompt re-opening of the intakes after the emergency is passed, and their main- tenance in a pervious condition, is required. Large rooms are proportionately easier to ventilate without drafts than are smaller ones, a practical argument for supplying an adequate cubic ak space to the soldier. Particularly if natural processes are em- ployed, the difficulties of adequately ventilating a small space are consider- able. These are caused not so much by the rate of the greater part of the air in a room as by the velocity of the air currents at their point of en- trance. If a space of 500 cubic feet be supplied with 3,000 cubic feet of air hourly, through an inlet having an area of 12 square inches, the move- ment of the entering air would necessarily be at the rate of 10 feet per second, or nearly 10 miles an hour; if the inlet have a sectional area of 24 square inches the rate would be 5 feet per second. In either case, hi such a small space, the air could not properly be distributed before reach- ing the person and a draft would be felt. If instead of 500 cubic feet of space 1,000 be given, the problem becomes much easier, for the small entering air current, in mixing with the air of the room, would be more easily broken up, and the soldier being able to get further from the open- ing the movement of air is less apparent. As to the point at which the sensation of draft is noticed, not only the rapidity of the air current but its temperature and the amount of at- mospheric moisture must be considered. Air currents having a tempera- ture of 55° to 60° F. and a rate of 1-J feet per second are not perceived. Those having a rate of 2 to 2^ feet per second are perceptible to some, a rate of 3 feet by most persons and that of 3|- by aU. Any greater rapidity gives the sensation of draft. If the temperature of the air be about 70° F. a rather greater velocity is not perceived, while if it be stiU. higher, 80° to 90° F., the movement again becomes more perceptible; and this is also the case if the temperature be below 40° F. A cold current of air is most noticeable if its humidity be excessive. From what has been said, it is obvious, in the prevention of drafts, that much of the air admitted to barracks during cold weather should be warmed. This necessity is recog- nized in the British service, in which it is officially prescribed that one- half the air so admitted shall be previously heated. In our own service, in some of the older barracks, this important point has been overlooked, though in those of late construction it has been provided for. The dif- ferent methods of warming the entering air are discussed later. In the prevention of drafts it is also important that entering air shall be broken up into small currents on being admitted to the squad- room, and for this same reason the inlets should be numerous and small. 458 THEORY AND PEACTICE OP MILITARY HYGIENE. Drafts rarely occur from outlets, unless their action be reversed by tem- porary conditions. In some instances, however, where a large ventilating flue runs down to the floor and the outlet opening is near its base, a strong and steady movement of air, uncomfortable to the feet, is established toward it during cold weather. This is often a cause of strong drafts on persons in front of open fireplaces. The remedy for this condition is obviously found in the multipKcation of outlets at widely separated points. Beds should never be placed in front of windows; since even if closed the leakage of cold air around the sashes, and the chilling of the layers of air in contact with the window-panes, may result in descending drafts upon the heads of the sleepers. In general, ventilating intakes should be at points not readily accessible to soldiers, and their operation and control should been trusted to men specially charged with their ser- vice. In this way the function of the inlets will not be surreptitiously interfered with, while the existence of any impleasant drafts wiU. early become known to the proper authorities. From what has been said it is apparent that the rapidity of entering air currents cannot, with comfort, be in excess of 3^ feet per second unless the air has been previously warmed ; though Putzeys believes that no cal- culations for the admission of air should be based on a rate greater than 2 J to 3 feet per second. This point is .all too frequently overlooked in our barracks. The ventilatiag shafts provided for the renewal of air are often incompetent, under existing conditions, to perform the service ex- pected of them; which service, if actually accomplished, would imply a rate of movement of air ordinarily quite impossible of attainment by natu- ral means, and which would be quite incompatible with comfort or health if it could be secured. Experience has demonstrated that if the amount of cubic space allowed in squad-rooms be so small as to require a consider- able number of renewals per hour to dilute the products of respiration down to permissible limits of impurity, the inmates of such rooms are subjected to discomfort from drafts. Even a renewal five times per hour would be too much. In the British army it has been foxmd that, in barracks with 600 cubic feet per head, the rooms are cold and drafty when any- thing approaching to 3,000 cubic feet of fresh air per head per hour is passing through; that is, a change of five times per hour for each 600 cubic feet of air space. A change equal to three or three and one-haK times per hour is generally all that can be borne under the usual conditions of warming in temperate climates, or that is practically attainable with natural ventilation; and if this be correct, assuming the hourly excretion of carbon dioxide by the soldier to be 0.72 cubic feet, 1,000 cubic feet should theoretically be the minimum allowance for the initial air space. In general, the frequency with which air may be changed depends to some extent upon the temperature and degree of moisture in it, whether it is warmed before being introduced, upon the appliances for introducing it and breaking it up, and upon the absolute size of the space to be ventilated. In connection with the rapidity of air currents, it is important to re- member that the influence of friction is very marked in this respect. The amount of loss produced by friction is often overlooked in estimating the size and character of inlets and outlets, and such neglect is apt to lead to VENTILATION. 459 unsatisfactory results and disappointment. The chief causes of loss are the following: 1. Length of tube or shaft. Here with equal sectional areas the loss is directly as the length; so that with a shaft of 30 feet as the standard, a shaft of 40 feet long would have an iacreased friction of one-third. 2. Si^e of opening. For simOar sections the friction is inversely as the diameter. Thus for two openings, respectively one and two feet in diameter, the friction at the smaller opening will be twice that of the larger. In this way dividing up an opening into a number of smaller ones, the aggregate of which is equal to the original opening, produces a loss by friction in the direct ratio of the diameters. An opening of one square foot divided into four openings, each of ^ square foot, loses in the ratio of 1 : ^, being respectively the diameters of the openings. When the shapes of the openings are not similar, the ratio may be stated as that of the square roots of the areas. Thus one square foot divided into nine openings, each equal to one-ninth of a square foot, wiU lose in the ratio of 1 : -J-, the square roots of the respective areas. 3. Shape of opening. A circular opening may be taken as the stand- ard—that being the figure which includes the greatest area within tlie smallest periphery. The loss sustained from the use of any other shape will be proportionate to its difference from a circle enclosing a similar area. Thus of two openings, each of one square foot area, the one being a circle and the other a square, the length of the periphery of the latter will be four square feet, of the former 3-|; therefore the velocity of the current through the square opening will be -^ or -^ of that through the circular opening. This is a point which is completely ignored in the construction of om- barracks; the ventilating shafts used, in their transverse section, being invariably rectangular. 4. Angles in the tube or shaft. This is a most serious cause of loss. The exact formula for this has not been distinctly determined, but it may be accepted, as in accordance with experiment, that every right angle diminishes the cvm-ent by one-half, so that two right angles in a tube would reduce it to one-fourth ; and so on. Yet it is no uncommon thing in oui service to find tubes and shafts bent at numerous angles to save ex- pense and appearance. If change of direction is necessary, the shaft should be gently curved rather than abruptly bent. The loss of head with a curved or U-shaped bend is only one-half as great as with two rectangular bends. 5. The presence of dust or dirt of any kind seriously interferes with the movement of air. This may of course be obviated with a moderate amount of care and attention, but in practice it rarely is. The gratings on ventilating shafts are often fastened in so securely as to render their removal for purposes of cleanliness extremely difficult of accomplishment without permanent injury to the building. It is advisable generally slightly to widen the openings of shafts, especially if they are of small diameter, as the current tends to be contracted and obstructed at that point, and loss of head results. At every change of direction the same thing takes place. Hence the desirability of rounding-off angles as much as possible, where they cannot be altogether avoided. It is best to have the sections of shafts circular or elliptical instead of rectangular; for not only 460 THEORY AND PRACTICE OE MILITARY HYGIENE. is there less loss by friction origiaally but there is less chance of lodgment of dust and debris, and the shafts can be more easily and thoroughly cleaned. It must not be overlooked that under certain circumstances the specific gravity of vitiated air, as compared with piu-e air, may be often as import- ant as friction ia hindering ventilation. Superficial and Cubic Space. — Squad-rooms should never have a height of less than 10| feet, and a height of 11^ to 12 feet is preferable. Above 12 feet the additional height should not betaken into consideration with reference to the ventilation of barracks, and a height greater than this need not be provided for barracks in temperate climates. Under no circumstances should very high ceilings be allowed at the expense of floor space, under the impression that proper cubic space is thus provided. Excessive height increases cost of construction and heating, and renders the maintenance of cleanliness difficult. It also to a certain extent inter- feres with ventilation by means of windows ; since the great size and weight of the sashes required under such circumstances would forbid carrying the windows close to the ceiling, and an accumulation of stagnant air occurs above their level unless special means for its removal are provided. Floor space and cubic space are both important factors in the ventila- tion of barracks. In general, the amoimt of cubic space required depends directly upon the rapidity with which the air of a squad-room can be changed without discomfort. While an abundance of cubic space is al- ways desirable, the idea is not rarely entertained by line officers that cubic space may take the place of change of air, so that if larger cubic space be available a certain amount of change of air may be dispensed with, or less fresh air required. This view is obviously quite erroneous, since even the largest space can provide sufficient air for a limited time only, after which the necessary amount of fresh air is required to be sup- plied hourly, whether the space be large or small. In our service, even the latest barracks allow but 56 to 60 square feet of space, per capita, in squad-rooms, and in nearly all old barracks the superficies available per man is far less than this amount — which is about the floor space provided in the British service. Morache regards 100 square feet of space as the proper amount to be supplied to each healthy soldier, but this area appears to be slightly larger than necessary and would therefore unduly increase the cost of sheltering troops. A provision of 85 square feet would, however, be desirable, and this amoimt it is quite within the power of the authorities to supply. This, in squad-rooms having an ordinary width of 24 feet, would allow a trifle more than 7 feet of running wall space to each soldier, and would provide an open space of about 4 feet between beds. Certainly such an allowance to the soldier cannot be regarded as extravagant. As to the minimum amount of air space which should be provided for each man in barracks, there can be no doubt that in most armies an en- tirely insufficient allowance is made in this respect. In Austria, 540 cubic feet are allowed per capita; in Germany, 540 for cavalry and artillery and 450 for infantry. Laveran states that in the Belgian army the allowance varies from 350 to 420 cubic feet for infantry, with 490 for cavalry; but some barracks recently constructed in that service provide for 600 cubic VENTILATION. 461 feet of space per man. In the British army on the home stations, the amount to which each man is entitled was long since fixed at 600 cubic feet. In our own army it was prescribed in 1870 that north of the 36th parallel there should be a per capita allowance of 600 cubic feet, and south of that parallel of 770 cubic feet. In a report on the condition of our barracks and hospitals made in the year mentioned, it was shown that out of a total of one hundred and forty-one garrisons only thirty-nine were provided with as much as 600 cubic feet of space per man, whUe in seven stations the cubic space available was as low as 250 cubic feet. At the present time, chiefly as the result of the enlargement of the company organization, a number of our older barracks — originally intended for oc- cupancy by the smaller organizations of former times — afford by no means sufficient air space. The barracks now being constructed, however, pro- vide for an allowance of 660 to 720 cubic feet of space iu squad-rooms for each expected occupant. This amount, if it can always be secured, is a great improvement over the allowances for foreign armies; but it must^be remembered that the vast standing forces maintained by other nations render it necessary to economize in every possible manner with respect to their maintenance, and such countries as Italy, France, Germany or even England are financially unable fully to provide such accommodations as are well recognized to be to the best advantage of the soldier. In this country, with a small army and a large and wealthy population, no such economic considerations should prevail; and it should not be assumed, because our later barracks are already more spacious than those of rela- tively impoverished nations, that no further improvement is desirable in this respect. From what has been said establishing the floor space at about 85 feet per man, and the height of the room at 11^ to 12 feet, it fol- lows that the amount of cubic air space which should be available is, in round numbers, 1,000 cubic feet. This amount closely agrees with theo- retical standards. It has been stated that the excretion of carbon dioxide by the soldier under the conditions obtaining in barracks is generally re- garded as about 0.72 cubic foot per horn:, and it is elsewhere shown that the amount of fresh air necessary to dilute this down to the permissible limit of respiratory impurity is 3,600 cubic feet per hour. Experience proves that air in barracks cannot be changed, without special and expen- sive mechanical means of securing ventilation, much more frequently than three to three and one-haK times hourly without drafts being produced. With an allowance of 1,000 cubic feet of air space, to each soldier, all these conditions are properly satisfiied with almost mathematical exactness. For the proper dilution of emanations from the sick in hospital, a much greater amount of fresh air should be supplied than is necessary for soldiers in barracks; and the cubic space per capita must be proportionately en- larged to ensure its distribution without drafts, to the influence of which the sick are especially susceptible. In the German army, 1,300 cubic feet are required to be provided for each patient in hospital. Eegulations for the British army allow 1,200; those for the French army 1,400. In our own service no standard is established as to the amount of cubic space to be provided under the same circumstances. It is generally ac- cepted by military sanitarians that, in hospitals, a minimum of 4,000 cubic feet of fresh air per patient should be supplied hourly. If the change 462 THEORY AND PEACTICE OF MILITARY HYGIENE. of air is to be three times per hour and the best rate of the entering air currents be calculated at three feet per second, the cubic space should be at least 1,300 cubic feet. Considering, however, the immense benefit to patients of pure air, and the abundant practical experience of medicar offi- cers on this point, it is very desirable not to fix the floor and cubic space of hospital wards at the bare minimum of what may suffice ; and hence Notter and Firth justly advise that a cubic space of 1,500 to 2,000 cubic feet per capita should be provided for hospital wards. The minimum floor space, in hospitals as in barracks, should be not less than one-twelfth of the cubic space, which gives a minimum allowance of about 110 square feet for each patient in hospital — ^this being increased where possible to 150-160 square feet. Where means of illumination other than electric incandescent lights are employed, extra air space should be allowed for each burner in barracks and hospitals, unless special means for the removal of impurities resulting from combustion are provided. In foreign armies a larger cubic space is usually provided for the cavalryman than for the foot soldier, for the better dissipation of stable odors. In single habitations, such as officers' quarters, well furnished with chimneys and sheltering but few occupants under the same roof, the ques- tion of cubic air space is of little importance, since the cubic space avail- able is usually in considerable excess of the minimum provided for barracks. In determining the amount of cubic space in a room the method is simple if the room be square or oblong and has a flat ceiling. In such cases the three dimensions of length, breadth and height are multiplied together. If the room be of irregular form, other measures must be em- ployed. If rectilinear, such places can be divided up into triangles and then measured ; or if bounded by curved lines they can be divided up into segments of circles. It is more convenient to make the measurements in meters, or in feet and decimals of a foot, than in feet and inches. For the calculation of superficial and cubic space the following formulae may be employed: KULES FOE SUPBEPICIAL MeASTIBEMBNT. Area of circle = 3.1416 X square of radius! Area of circle = 0.0796 X square of circumference. Circumference of circle = 3.1416 X diameter. Diameter of circle = 0.3183 X circumference. Area of ellipse = 3.1416 X i long diameter x i short diameter. Area of square or rectangle = multiply together two sides perpendicular to each other. Area of triangle = base X i height. Area of any rectilineal figure = the sum of the areas of the component tri- angles. Area of segment of circle = f X chord X height. Rules for Cubical Measurement. Cube or solid rectangle — length X breadth x height. Solid triangle = section area of triangle X height. Cylinder — area, of base X height. Cone or pyramid — area of base X i height. Dome = area of base X f height. Sphere — diameter cubed X .5236. To the cubic space of the room, all recesses, such as doorways and window recesses, must be added in. AH projections, as chimneys, air- VENTILATION. 463 shafts or fixed lockers, should be deducted, and the cubic space occupied by the bodies of soldiers, generally estimated as about 3 cubic feet per man, must also be subtracted. The amount of air space taken up by furniture, lockers and bedding should, in addition, be taken into consideration, since the free space thus lost for purposes of ventilation is not small. In gen- eral, 4 cubic feet may be deducted for each bed with its accompanying bedding, and 4. 6 cubic feet for each movable locker of regulation pattern. The total deduction to be made in the case of each soldier in a squad-rooiji thus amounts to about 12 cubic feet. It has long been recognized that insufficiency of floor and air space in barracks is a potent factor in the occurrence of disease among soldiers, especially with respect to affections of a transmissible nature. Sore throat, headache and malaise are particularly induced by overcrowding and the deficient ventilation thus implied. In the investigation into the sanitary condition of the British army, in 1856, it was found that those regiments provided with the least spacious barracks invariably presented the highest death rates; and since that time an abimdance of evidence to the same efi'ect has been accumulated. As an instance in our own service it may be mentioned that, in 1896, it was shown by Owen, at Ford Bayard, that for every case of disease- — ^chiefly of tonsillitis and febricula — which occurred among organizations having a per capita allowance of 730 cubic feet of air space, there occurred 2.5 cases among organizations which had but 420 cubic feet per man. But in spite of the fact that the dangers of overcrowding are fairly well understood by line officers, it is none the less true that serious overcrowd- ing has occurred within the past few years at a number of posts. From the several recruiting depots such conditions have been frequently reported. At Fort Yates, in 1895, one barrack was stated to have been so crowded that, to get to bed, certain men were obliged to clamber over the foot rails of their bunks or crawl over beds belonging to other men. From Fort Sill, during the same year, an almost identical condition of affairs was re- ported; In 1892, at St. Francis Barracks, nearly within the tropics, it was reported that the bunks in the squad-rooms were almost touching each other and only 300 cubic feet of air space were available per man. Guard houses especially, during the past ten years, have been reported as overcrowded; and in 1894, at Fort Wingate, in a hot climate, the air space available for each inmate was stated to have been but 217 cubic feet. Many other instances of overcrowding, in lesser degree, have been reported during the past few years; these being apparently due not so much to ignorance as to disregard of the first principles of hygiene on the part of the executive authorities. While much may be excused during time of war, when military necessity may at times temporarily overrule certain sanitary requirements, there is absolutely no justification for the over- crowding of barracks in time of peace. If the proper capacity of thB buildings at a post is exceeded, it becomes the plain duty of the sanitary officer to recommend that a sufficient ninnber of men be sent to other sta- tions, so as to allow those left behind the floor and air space to which they are justly entitled. This attitude should be vigorously persisted in despite the opposition which may be excited on the part of line officers, who, from personal motives, are unwilling to see their commands reduced in numbers. 464 THEOEY AND PEACTICE OF MILITAEY HYGIENE. It _is certainly unfortunate that our regulations do not explicitly pro- vide for a minimum floor and air space for the soldier in barracks. In the British army, at home stations, each soldier is officially entitled to a minimum of 600 cubic feet of air space, and the door of each squad-room is plainly marked with the floor spaije and cubic air space of the room, together with the maximum number of occupants authorized under regula- tions. It would be of great sanitary advantage if a similar custom were established in our own service, and thus do away with the too frequent practice of crowding one hundred men into quarters perhaps originally in- tended to shelter but seventy-five. Even where the floor and air space is theoretically ample, it should not be forgotten that their value may be largely destroyed by defective facilities for ventilation. Amount of Fresh Air Required. — The quantity of air required for the ventilation of any confined space will naturally depend upon the nature and amount of the air impurities requiring dilution and removal; these impurities, for aU practical purposes, being created by respiration and artificial lights. Of these various impurities, no matter whether from respiration or illumination, the carbon dioxide is accepted as the chief measure of air vitiation; not because the carbon dioxide exists in such amount as at once seriously to influence health, but because it appears to be present in a constant ratio with other offensive and dangerous im- purities. As its quantity is very readily determined with sufficient ac- curacy for all practical purposes, it is therefore taken as the amount of the other impurities in general, and it becomes important to establish a limit of permissible impurity in this respect. This is fixed by Eoth and Lex, de Chaumont and others, as already stated, at 0.6 parts per 1,000, which includes 0.4 of initial atmospheric carbon dioxide; they also placing the hourly elimination of carbon dioxide for men of the military class, under ordinary conditions, at 0.72 of a cubic foot. The amount of fresh air necessary to exactly dilute this quantity of carbon dioxide down to per- missible limits is 3,600 feet per hour, or one cubic foot per second. Wliere only 600 cubic feet of air space is provided per man, it is obvious that the air should be changed six times per hour to ensure a proper de- gree of purity. In practice, however, as already stated, it has been shown that for temperate climates the air of a room cannot usually be changed by common means of ventilation much more than half as frequently with- out the creation of unpleasant drafts. Hence, for barracks which pro- vide a per capita air space of much less than the standard of 1,000 cubic feet already proposed, it is plain that the supply of the desirable amount of fresh air wOl rarely be accomplished, except with special mechanical apparatus and at considerable expense — ^the latter being usually greater than the military establishment can afford to bear. This latter objection was fuUy recognized by the British commission on barracks, which finally decided, on this account alone, to recommend that as a minimum each soldier in squad-room, having 600 cubic feet of space per capita, should be provided with 1,200 cubic feet of fresh air per hour; though the commis- sion at the same time distinctly stated that this amount was quite insuffi- cient for the dissipation of odors at all times and seasons. The economical objections to supplying an amount of air known to Tdb desirable are also recognized in the Massachusetts school laws, which require a minimum VENTILATION. 465 hourly delivery of 1,800 cubic feet of fresh, air per capita, this beiug less than the amount theoretically required even for children. In our own service it is only attempted to renew the air twice hourly, which with a cubic space of 720 cubic feet in our new barracks means 1,440 cubic feet of fresh air per hour, or less than half what should be supplied. By start- ing with a proper cubic space, however, these practical diflficulties in the way of an economical supply of sufficient fresh air are avoided ; and there is no reason why, in squad-rooms of sufficient capacity for the number of men they contain, the air should be vitiated beyond the limits of permis- sible impurity even with simple means of ventilation. It is true that the practical limit of purity which can be reached in the air of barracks, even if the cubic space be small, depends upon the sum which the government will expend for its attainment; but, as already stated, cost cannot be wholly disregarded, and it is probably ultimately cheaper, and certainly more satisfactory from the military if not the sanitary standpoint, to pro- vide sufficient air space at the outset and accomplish the necessary change of air by other than mechanical contrivances. Since for soldiers in barracks 0.72 cubic foot of carbon dioxide may be regarded as the average hourly output per capita, and the amount of fresh air required per hour to dilute this carbon dioxide to permissible limits is 3,600 cubic feet, the following table shows the amount of fresh air necessary, under different conditions of cubic space, to dilute the car- bon dioxide of respiration to the standard of total permissible impurity of 0.6 per 1,000 volumes of air, inclusive of the amount — 0.4 — originally present in the air. Amount of cubic space for one soldier, in cubic feet. Batlo per 1000 of COj Amoijnt of air necessary Amount necessary to from respiration at the end to dilute to respiratory dilute to the given of one hour, if there standard of 0.6 standard every hour has been no change of air. durlnff the first hour. after the first. 100 7.20 3,500 3,600 200 3.60 8,400 3,600 300 2.40 8,300 3,600 400 1.80 3,300 8,600 500 1.44 8,100 3,600 600 1.20 3,000 3,600 700 1.03 2,900 3,600 800 .90 2,800 8,600 900 .80 3,700 3,600 1,000 .72 2,600 3,600 This table of course refers to apartments which, like squad-rooms, are occupied a number of hours consecutively. It is readily apparent that while the air of even the largest rooms ultimately becomes unfit for respira- tion unless it be properly renewed by ventilation, the larger the air space the less is the necessity for the frequent renewal of air and hence the less the chances of draft. Thus if a space of 100 cubic feet be allowed the soldier, it must have its air changed 36 times in an hour, if the proper amount of 3,600 cubic feet of air are to be given; while the space of 1,000 cubic feet need only have it changec^ three and one-half times in an hour to secure equal ventilation. In considering places in which the occupants are actively employed, as drill halls or gymnasia, the amount of air to be supplied must be pro- 30 466 THEORY AND PEAGTICE OF MILITARY HYGIENE. portionately increased. In light work, accordiag to Notter and Firth, the carbon dioxide eliminated per hour is nearly 0.006 of a cubic foot per pound of body weight, and in hard work more than double that amount. Thus for the soldier, at the average weight for our service of 145 pounds, there is hourly eliminated 0.86 cubic foot of carbon dioxide during light work, which would properly imply a delivery of 4,140 cubic feet of fresh air during the same period. For healthy persons, the number of cubic feet of air required per hour may be found by dividing the amount of carbon dioxide exhaled during the same period by the permissible limit of respiratory impurity ; and this standard is now generally accepted by sanitarians. ^ — D It is conveniently expressed by the following formula : p " where E = the amount of CO, exhaled by one individual in an hour, P = the lim it of admissible impurity above the amount of CO, normally present in the atmosphere, stated per cubic foot, and D = the required delivery of fresh air in cubic feet per hour. With respect to the amount of fresh air per capita to be delivered hourly in hospitals, experiments seem to show that the amount required as a minimum by the sick is at least one-fourth greater than in health. For military hospitals at least 4,000 cubic feet, in round numbers, should therefore be demanded. In dealing with infectious cases a much greater amount of fresh air must be hourly provided, reaching 5,000, 6^000 or an even greater number of cubic feet if possible — in fact, with such cases the supply should be practically unlimited. Natural Ventilation. — A room is said to be naturally ventilated when no special measures are taken to ensure the entrance and removal of air, but reliance is had upon perflation through open doors and windows, leakage through their cracks, the percolation of a certain amount of ah' through walls, and on the aid of chimneys which serve for heating and have not been specially arranged to assist the changing of air. All these methods depend upon certain physical processes which are also made use of in artificial ventilation, and it is thus difficult to define exactly where natural ventilation ends and artificial ventilation begins. Though natural ventilation is usually sufficient for the proper renewal of air in officers' quarters, it is quite inadequate, by itseK, in the case of barracks ; but when combined with such power as can be got from ordinary sources of warming and lighting, together with special arrangements for securing the maximum assistance from outside air currents, natural ventilation will be of great value in securing the desired results. The amount of air which percolates through a barrack wall is often considerable, though \mfortunately so many factors influence its passage as to make it an rmcertain source of supply. Among these factors, press- ure of the external air, as seen in winds blowing against the exposed side of a building, is of great importance, and in the absence of such wind a relatively smaller percolation of air takes place. The thickness of walls and the material of which they are constructed also exert a powerful in- fluence. Many observers have investigated the porosity of building ma- terials by determining the amount of air, under varying pressures, which would pass through a given superficies and thickness of the material in a given time, and all are agreed that walls of the usual materials may at VENTILATION. 467 times allow considerable air to pass through them — this insensible percola- tion often contributing largely to ventilation. Pettenkofer found that the passage of air through the walls of an ordinary dwelling-house, under cer- tain conditions of wind and temperature, was sufficient to change the air of a room of 2,650 cubic feet capacity once every hour. Permeability to air, however, varies greatly with the nature of the building material used. Marble, stone and wood are not very permeable, and cement is less so. Plaster is quite porous, and dry bricks let air pass readily. By covering a brick with wax, save for a small space at either end, and attaching a glass funnel thereto, Pettenkofer was able to blow out a candle flame through the full length of the brick. Moisture, however, practically ren- ders a wall impervious to air, and during rainy weather the passage of air into buildings, through their walls, ceases almost completely. Lathing and plastering somewhat diminish the passage of air, while papering or painting with oil paints almost completely prevent it. For these reasons, the porosity of walls cannot be constantly depended upon as a means of ventilation and should in practice be disregarded in making arrangement-s for the renewal of air in barracks. Analogous in its results to the entrance of fresh air through walls and crevices, is the escape from the room, into the atmosphere at large, of gase- ous impurities. This is accomplished by diffusion, the rate of which is inversely as the square root of the density of the gas. Pettenkofer and Eoscoe showed that diffusion readily took place through brick and stone, though moisture greatly interfered with the rapidity of the process. Through chinks and openings resulting from imperfect carpentry, gaseous impurities diliuse fast. Eoscoe found that on evolving carbon dioxide in a room the proportion of this gas in the air was reduced as much as one-half in one and one-half hours. Gr^hant, after sealing up the cracks of a room with paper, passed in carbon dioxide until there were 35.7 parts of the latter per 1,000. In twenty-four hours this amount of carbon dioxide was re- duced to 0.8 per 1,000. For practical purposes, however, it has been shown that the amoimt of diffusion in the air of rooms is quite insufficient for its proper purification under ordinary circumstances; and in addition, organic matter, which is molecular and not gaseous, is not affected by it. Hence the purification resulting from the diffusion of gases may be regarded as of only secondary importance in the problem of ventilation and not to be taken into calculation. Next to the percolation of air into barracks through their walls and the cracks around doors and windows the simplest kind of ventilation, which more properly is aSration, is that through open doors and windows ; but this method, except in the warmest weather, causes impleasant drafts, and for this reason cannot be employed at all times. Neverthe- less, when weather permits, advantage should always be taken of it by troops in barracks. It is difficult to appreciate the vast amount of air which is admitted to squad-rooms through opened windows ; this quantity being out of all proportion to what can be accomplished even by the best artificial arrangements. Where the outside air is moving at the rate of two miles per hour, a rate which is almost imperceptible, on passing freely through the side windows of a squad-room 24 feet broad it wUl change the air of that room 440 times per hour. With a moderate breeze the 468 THEORY AND PRACTICE OF MILITARY HYGIENE. FIG. 212. number of times the air is renewed is greatly increased, and it is obvious that no such powerful ventilating action as is given by perflation can be obtained in any other way. In some foreign armies the great value of perflation is fuUy recognized, and in the French service it is laid down in regulations that, unless the weather be very inclement, in the morniag as soon as the men have arisen and are dressed, all the windows on one side of the squad-room are to be opened; and when the barracks are temporarily vacated, as during drills, they are always to be fully aired. Similar regulations obtain in the British army. In our own service no such rulihg is in force, but the windows of the squad- room should be freely opened from reveille until 9 a.m., and again for an hour about evening, regardless of any but ex- tremely stormy weather. The times chosen shoidd prefer- ably be when the greatest number of men are absent on driU. or other duty. If the climate and weather be suitable, sev- eral or aU of the windows of the leeward side of the squad- room should be constantly kept open. Day -rooms are pro- vided in nearly all our barracks, and to these the men may resort without inconvenience during the period of airing. These precautions would seem too obviously necessary to require formal instruction, but experience shows that without constant oversight even the simplest sanitary rules will be disregarded by soldiers. Since windows play such an important part in natural ventilation, it is desirable that they be large and extend nearly to the ceiling to prevent stagnation of the upper layers of the air. . To ensure thorough lateral ven- tilation by perflation it is important that, in their location, windows should be directly opposed to each other. The upper sash should also be freely movable. A number of slight modifications of window sashes, in form or arrangement, have been proposed with the idea of admitting a limited sup- ply of air in such a way as to prevent the creation of drafts; and some of these, from their simplicity and efficiency, are of much value for the military service. The best and simplest device for the admission of cold air consists merely in raising the lower sash by an ac- curately fitting strip of wood, six or eight inches high and sometimes perforated horizontally with small holes. By this arrangement a space is left between the lower and upper sashes through which the air passes in a thin sheet and, being directed upward, curves into the room without perceptible draft (Fig. 212). During cold weather the window can of course be readily closed. A simQar arrangement con- sists in protecting the top of the upper sash by a slop- ing board. On lowering the upper sash two openings are thus created, the one between the two sashes often serving for the ingress of air while the opening at the top of the window serves as an outlet (Fig. 213). With the same idea, others have proposed to fit window sashes with double panes of glass, an open space being left at the bottom of the outer and the top of the inner panes. This arrangement was tried in the French army, and -was found to be unsatisfactory by reason of the fact that the amoimt Yl :i ifl .^ Fig. 313. VENTILATION. 469 of fresla air entering could not be controlled in cold weather, and also be- cause dust rapidly settled between the two panes of glass and could not readily be removed. Double windows, in winter, may be used in the same manner — the swinging panes in the lower outside sash being opened and the upper inside sash beiug slightly lowered. It has been advised to put perforated plates of heavy glass in the upper part of windows ; the per- forations being conical and having the larger ends toward the interior, to cause the entering air currents to diminish in force. These apertures are supposed to be closed, as required, by a hinged or sliding plate of glass. Perforated sashes have also been made by boring holes in the lower part of the upper sash. Such a procedure weakens the frame and, like the pre- ceding arrangement, is not desirable for military use. In some French barracks, simple openings made in the lower sash bar, guarded on the inside by a metal plate fixed parallel to the window frame so as to divert the air upward, have been tried. They possess no special advantages. Slats of glass, zinc or iron, constructed on the Venetian blind principle, have been recommended to be inserted in window frames. They are mentioned merely because they have been used in some foreign services. Swinging glass sashes are used in a number of foreign barracks for the upper half of the window. These should turn on horizontal rather than vertical pivots to avoid drafts. Some- times these swing, as in some German barracks, from the lower border; most of the entering air being thus directed up- ward. Swinging sashes of this character woidd undoubtedly be valuable for some of our southern posts in this country. During the day-time doors serve as a certain means of ventilation ; but at night, when all the men are present and vitiation of the air is greatest, they are usually closed. Squad-rooms are often supposed to be partially ventilated through doors openiog into haUs ; but the air in the latter may be impure and the means provided for its renewal be insufficient, as at Washington Barracks, and may be of worse character than that of the rooms it is intended to benefit. This is particularly the case in barracks with dark longitudinal central hallways, of which fortunately but few exist in our service. On the other hand, where the hall is central, trans- verse, well-lighted and properly ventilated, it serves, together with the stairways running from basement to roof, as an efficient aspirating shaft, in the direction of which there is a general tendency of the air throughout the building to move. Especially in cold weather this movement is quite decided, and it is generally best to make use of it. Under such conditions, transoms should be placed over doors leading into the haU to give exit to air currents. Location and Size of Ventilating Openings. — The best position of inlets for fresh air is not the same under all circumstances. Practically their location should vary with season, mode of warming, size and shape of rooms, and forces for distributing air. They shouldnot be too large in- Fia. 214.— Swinging Window Sash. 470 THEOEY AND PEACTICE OF MILITARY HYGIENE. FIG. 315. -Method of Warming and Admitting Fresh Air and Re- moving Foul Air, as Used In the British Army. dividually — since any system that does not allow the gradual entrance of air is bad — and should be distributed around the squad-room. If placed too near outlets, the entering fresh air may at once escape without mixing with that throughout the room, since air always moves on the line of least resistance. Theoretically, the proper place of inlets is at the floor of the room; but if they are so located in cotd climates the entering air must be warmed ; for soldiers wiH not tolerate chilling of the feet by cold drafts, and inlets offending in this respect are certain to be closed. Entering air may be warmed by being admitted under stoves surrounded by a metal hood, or through boxes containing hot water or steam pipes. In our new barracks the steam radia- tors are located under the windows and directly in front of the fresh air intakes. The entering air. is diverted upward along the flutings of the radiators, is warmed and also continues its vertical direction for some feet after leaving the radiator (Fig. 216). Provision is also made so that fresh air can be admitted directly without passing through the radiators, if desired. In the British service, fireplaces are much used for the heating of barracks, and a part of the entering air is warmed by being passed through ventilating flues in the chimney. This method is unsatisfactory in such severe winter weather as may be expected in the northern parts of this country, although well adapted to moderate degrees of cold. Where inlets are placed in the floors their cleanliness must be carefully looked to, as otherwise they are liable to collect dust, sputum, cigar stubs, match ends and other refuse. If the entering air cannot be warmed, it should be let into the room at a height of nine or ten feet above the floor, and be directed upward. It thus passes up, is partly warmed by contact with the heated plaster of the ceiling, along which it has a tendency to spread in a thin sheet, and then mixes gradually with the air of the room as it falls. In the British army, half the air brought into barracks is admitted in this way ; the other half is warmed before entrance and is admitted at a lower level. In general, for temperate climates, where the air can be heated the entrance should be near the floor. If heating can be accomplished the location of the inlet below is in all respects satisfactory ; if it cannot be done, the inlet must be located near the ceiling — theoretical considerations to the contrary. It should be understood that a system which, in practice, works satisfactorily is preferable to one which, though excellent in theory, operates badly. The location of outlets is a matter of the greatest importance in the ventilation of barracks ; and, like that of the inlets, their position should VENTILATION. 471 vary according to circumstances. In general, the positions of inlets and outlets are interdependent. The fact that in heated and occupied rooms the upper layers of air are the most vitiated, points to the theoretical im- portance of withdrawing the air from a higher level. Moreover at night, which is the period of the greatest vitiation in respect to the air of squad- rooms, the ascent of the respired air and its impurities is rapid, not only from its higher temperature but from the force with which it is propelled upward by recumbent sleepers. On the other hand it has been argued by many that it is better for the foul air to pass off below the level of the person, so that the products of respiration may be immediately drawn down below the mouth and be replaced by descending pure air. But the resistance to be overcome in drawing down the hot air of respiration is so great that there is a considerable waste of power, and the obstacle to the discharge is sometimes sufficient, if the extracting force be at all less- ened, to reverse the movement so that fresh air forces its way in through the pipes intended for discharge. It is plain that the location of aper- tures for the removal of air at points near the floor is opposed by all natural laws governing the movement of air; but nevertheless, where the entering air is unwarmed, this arrangement is probably the best in practice for cold climates. Careful experi- ments seem definitely to show that the most success- ful results are obtained, in respect to the mixing of the entering air with that already present, when the idlet is high up in the wall and the outlet is low down diagonally on the opposite side of the room; but to operate such a system the air in the extracting shaft must be warmer than that outside , and the practical efficiency of ventilation will vary with the difference be- tween these temperatures. Usually the heating of the air in the extracting shaft is readily accomplished by some simple arrangement. Often the outlet shafts are built into the chimney and the heat from fires below is thus utilized for ventilation. Where central heating is used, this method is generally employed; though sometimes steam or hot water coils are placed around the base of the shaft for greater heat, as is done in some of our new barracks. With open fireplaces, the chimney itself serves as an excellent extracting shaft. Where ordinary stoves are used for heating, probably the best arrangement consists in running a large air-shaft down Fig. 216.— Arrangement for the Admission of Warmed Air Into Squad-Sooms. Direct-Indirect system. 472 THEOEY AND PRACTICE OF MILITARY HYGIENE. to the floor, preferably in the center of the squad-room, and allowing the stove-pipes to enter this shaft toward the upper part. Openings are then provided at the top and bottom of this shaft — as in fact should be done with all outlet flues — capable of being opened or closed as required; so that in winter the air is drawn out from near the floor level, while in warm weather, when the stoves are not in operation, the upper valve may be opened and the heated air of the apartment thus allowed to escape natu- rally. This arrangement is partially shown in the accompanying diagram, in which, however, the upper outlet does not appear, since that portion of the air-shaft in which it should be located is cut away to show the arrange- ment of the stove-pipes. Where a single stove is used for heating, the mistake has at times been made of carrying the pipe directly upward, sur- rounding it by a Hue of larger caliber where it passes out of the room, and in some cases ex- tending this larger pipe nearly down to the stove. Under such conditions, much of the heated en- tering air at once escapes without mixing with that in the room, to the det- riment of not only ven- tilation but warmth. Where stoves are used, the pipes should be ca)r- ried horiiiontally for some distance before entering the outlet shaft and pass- ing upward, so that the points of intake and dis- charge may be well separated and as much heat as possible be utilised in warming the room. Iv warm climates, or during hot weather when fires are not kept up, the outlets are obviously best located in or close to the ceiling; ridge ven- tilation probably giving the best results. Of several outlet tubes, under such conditions, the highest outlet is usually the point of greatest discharge, and sometimes the only one — ^reverse currents perhaps being established through the other shafts. It should not be forgotten that the heat re- sulting from illumination may be sufficient to change the usual direction of air cmrents, and thus the problem of renewing the supply of air by daj' and night may be double, no single arrangement being entirely satisfactory. If possible, ventilating outlets should not be located over beds, since a re- version of air currents, as at times occurs, woiild create descending drafts of cold air on the men below. On inquiring as to the minimum size of the ventilating space through which the necessary air has to pass, it is apparent that this entirely de- pends upon the rapidity with which air can be taken through the space without its movement being perceptible or injurious; this, in its turn. Fig. 217.-Diaeram Showing Use of Stoves in Assisting in Ventila- tion, Together with Location ol Inlets and Outlets. VENTILATION. 473 being secondarily dependent upon the size of the cubic air space provided. The theoretical size for any required change of air, supposing that the con- ditions are constant, can be obtained by the use of the followiag formida, suggested by de Chaumont : 300 f Vli(t-t')X 0.003) - I O'" <^- In this formula D = delivery per hour in cubic feet; 200 is a con- stant; f is the coefficient of friction; h is the height of the heated colunm of air; t = its temperature; t' that of the outer air; 0.002 the ratio of expansion of air for each degree F. ; I = inlet and = outlet, both in square inches. It is commonly stated that, as heated air expands, the inlets should be sKghtly less in area than the outlets. This, however, is so slight that it may safely be disregarded imder usual conditions, since with a difference in temperature of 30° F. air expands only one-seven- teenth of its volume. Carpenter gives the following figures as showing the ventilating area, in square inches, required for each 1,000 cubic feet of space under different rates of renewal of air. Number of Times Air is Changed Per Hour. per second. 1. 2. 3. 4. 5. 6. 1 40. sq. in. 20 13.3 " 10 8 6.7 " 80 sq. in. 40 " 26 " 20 " 16 " 13 " 120 sq. in. 60 " 40 " 30 " 34 " 30 " 160 sq. in. 80 " 53 " 40 " 34 " 37 " 300 sq. in. 100 " 67 " 50 " 40 " 33 " 240 sq. in. 2 130 " 3 80 " 4 60 " 5 48 " 6 40 " As the movements of air out of and into barracks vary in rapidity ac- cording to the difference between internal and external temperatures, it is obviously out of the question to set any one standard of size for ventilatkig apertures which would be suitable for all conditions ; even if the influence of wind be excluded, which is impossible. The only way is to adopt a size which will meet most cases, and also provide means of altering the supply according to circumstances. Sanitarians appear to have generally accepted as standard, for temperate climates, an area per man of twenty- foin square inches for inlet and the same for outlet. In the barrack regu- lations of the British army the sectional area of the ventilating inlet is fixed at twenty-four square inches per capita ; but to hourly supply through this space the 3,600 cubic feet of air necessary for the proper dilution of respiratory impurity would imply an entering current haviag a rapidity of six feet per second, which is too great for comfort. With a three foot rate, only 1,800 cubic feet of fresh an could be supplied hourly through an apertvire of this size ; and with a rate of this proper character it is clear that theoretical standards, as aheady discussed, demand a ventilating space of 48 square inches per man. To give the best results each indi- vidual inlet opening should not be larger than 48 to 60 square inches, and no outlet should have a sectional area greater than one square foot. With openings of this size located aroxmd a squad-room, disagreeable currents are avoided and the general distribution of fresh air is more certain. 474 THEOEY AND PEACTICE OF MILITARY HYGIENE. incs'air brick Pig. 218.— Jennings's Air-Brick. Intake Apparatus. — Besides the natural admission of air iato bar- racks through walls, windows and doors, a number of special devices have been proposed to permit of the entrance of a sufficient amount of air with- out the creation of drafts. While designed primarily for the introduc- tion of air, these arrangements, under varying conditions of wind, tem- perature and other factors, may also at times serve as outlets. For the admission of air, perforated bricks are sometimes built into walls. These bricks are usually pierced with conical holes of about one-fifth of an inch in diameter, the base pointing internally better to ensure the grad- ual entrance of air. The usual size of the brick beiag 3x9 iuches, the vmited venti- lating area is about 11^ square inches. An- other common size is 6 x 10 inches, having an open area of 24 square inches. The air passing in through these holes is so divided that it gives no draft. These bricks are best placed just behind and concealed by the skirting board. Jennings' air- brick is another form of these inlets, being usually placed in the walls near the ceiling. The outside air, before passing into the room, is led into a small chamber where much of its suspended dust is deposited. An open iron frame of the size of a brick, covered with an iron grating and with a valve to close it, is an arrangement for the admission of air which gives fairly good results. A simple shaft, capped with a swinging cowl so arranged as to always present its open mouth to the direction from which the wind is blowing, affords a ready means for the forcing in of fresh air. These swinging ven- tilators, however, usually become rusty and hence noisy in their action; beside which they may become jammed or be rusted into a _^_^ fixed position, in which case they are liable to be converted into aspiratory shafts and serve for the egress instead of the entrance of air. Windsails, as used on board ship, are similar in principle to the above. A fixed cowl for perfla- tion through a downcast shaft is made from a tube, the up- per end of which is funnel-shaped and is surmounted by a top shaped like an inverted cone. The wind is thus de- flected downward from whatever direction it may come. Both these forms of ventilator may give rise to strong air currents during high winds, while in still and warm days their action may be reversed. In some cases, ordinary tubes, as proposed by Tobin, provide for the introduction of air from the outside at the floor level and then up a vertical tube inside the room to a point about six feet in height. This gives a vertical direction to the entering current, which is retained for several feet further before it begins to spread and descend. The action of each tube is much affected by the direction of the wind — and like the forms of apparatus just mentioned it may, in fact, be reversed altogether. In some modifications of these tubes the air is vz7 Fig. 219.— Down- cast Shaft with Fixed Cowl. VENTILATION. 475 ^ Fig. 220.— Sherlngham Valve, sectional view. Front and warmed by a gas-jet before entrance. These tubes are liable to get dirty and full of cobwebs, and do not satisfactorily meet the needs of the mili- tary service. One of the best forms of inlet, where unwarmed air is to be admitted, is the Sheringham valve — much used in foreign armies. It consists of a trough having its rear wall removed and pivoted at its lower interior border. Usually it is located about two feet below the ceiling of the room. Air passes in through an open- ing in the wall behind the trough, and is directed upward by its internal lip. The ventilator can be opened or closed as de- sired, usually being so balanced as to fall open by its own weight. As used in the British service, the size of the in- ner opening is 27 square inches. This is somewhat larger than the area of the out- side intake, and the velocity of the entering air is proportionately lessened. The wind blows through these valves and the movement of air is therefore variable. They are often outlets; in fact it depends upon circumstances as to whether they act as inlets or outlets. Very little draft is caused by them save in high winds, and they are generally regarded as very satis- factory. Similar to these valves, but not so readily operated, are drawer- shaped inlets having no back wall. These work horizontally back and forth. When pulled out into the room, air passes through them and is deflected upward by the interior border. The ventilating cornice, used in the British and other foreign services, is especially designed to limit the liabUity to drafts. In character it does not greatly differ from the Sheringham valve, and, like it, is placed covering an aperture in the wall, a little below the ceiling; being consid- erably larger than the opening it guards. The top is covered with zinc pierced with numerous small holes, save directly over the aper- ture in the wall. In this manner entering air currents are completely broken up and the fresh air passes insensibly into the room. The to- tal area of the small holes in the top of the cornice should be six or eight times the size of the orifice of admission. Sometimes a valve is also used with this apparatus. In this connection, it may be stated that all delivering air-shafts should be short and capable of being easily cleansed. This is an important matter, and should lead to the rejection of aU plans in which the reverse prevails. With long shafts, friction is great, dirt lodges and the entering air is im- pure. As already stated, intakes should be numerous and small rather than large or single, and should preferably be enlarged where they enter the room. This is important in preventing drafts. For the same reason their external orifices should be partially protected from the wind, since otherwise the latter may blow through them too rapidly Sometimes the |S^^°Z'fes ^J^^^^^ Fig. 221.— Ventilating Cornice, al view. Front and section- 476 THEOEY AND PEACTICE OF MILITAEY HYGIENE. \ intake sliaft is curved for this purpose, or an overliangiag shelf or hood may be used. Means should be taken to divert the air upward on enter- ing the room. Gratings over both ends of the shaft are important to exclude foreign objects, but they should be capable of ready removal for purposes of cleanliness. Since gratings reduce the size of the openings to some extent, an allowance in this respect may have to be made ; with ordinary registers, this generally amounts to about 30 per cent. Where wire netting of large mesh is used to protect the opening no special allow- ance in this respect is required. AU intakes should be provided with valves, so that they may be closed if required. They should always open externally at least one foot above the surface of the ground, and the latter should be open, dry and well policed. If possible, the neighboring ground should be covered with short grass to limit the creation of dust. AU shafts should be frequently inspected as to their cleanliness and perviousness, and this is especially important in cold weather. Mention has been made of the special tendency on the part of soldiers to stop them up at such times. Combined Inlets and Outlets. — ^A num- ber of simple but excellent arrangements for the renewal of air in rooms have been proposed, depending for their action on natural processes. These are usually planned to act at the same time as both inlets and outlets. A single verti- cal shaft has sometimes been used for this pin- pose, double currents of air being established ^^^ through it. This is a crude plan, as there are no means of distributing the air, and the fric- FiG. 233.— Watson's Tube. tion of the Opposing currents — together with the action of winds and conditions of temperature —is often so great as to stop the movement of air through it. To avoid these inconveniences, Watson suggested the simple plan of merely divid- ing the air-shaft by a longitudinal partition. With this arrangement, when placed in the ceiling of a room, ascending currents are established by the heated air through one compartment, while cold air flows down through the other compartment to replace what has passed out. In shafts of this character, accidental circumstances, such as the wind, sun's rays or proxim- ity of artificial heat, wiU determine which channel is outlet and which is in- let. They are so far better than the single tube in that the partition divides the currents and prevents friction, but there is irregularity of action and the distribution of air is not good. The Muir ventilator is similar to that pro- posed by Watson, consisting merely of a box or shaft divided longitudinally into four compartments by diagonally located partitions. The upper part of the shaft, where it projects above the roof, is protected by slats ; these being inclined upward to prevent down-drafts and assist the movement of up-currents by the aspiratory action of the wind. Through the heat of the sun and action of the wind, two compartments of this ventilator serve as outlets, while descending currents are established through the others. The McKinnell ventilator is a perfected type of the Watson tube^ It is composed of two cylinders ; one inside the other and separated by an in- terval having a total area equal to the sectional area of the inner tube. VENTILATION. 477 [G. 223.— Muir Ventilator. B, Transverse section of same. This interior tube projects beyond the external one at both top and bottom. The inner tube is the outlet tube ; this being so because the outer casing of air maintains a higher temperature in it, and it is also made higher than the other and is protected by a cowl above it. As the warm air escapes through the inner tube a corresponding amount of cold air flows in through the interspace between the pipes, and is di- verted by the flange on the lower end of the inner pipe toward the waUs of the room. A lamp or gas jet swung immediately below this ventilator adds greatly to its efficiency at night. It has been much used in foreign barracks. Simple ridge openings may be used in one-story buildings and are generally employed in our older style of post hospitals. During the Civil War es- pecially they were much used. They ventilate most thoroughly, but snow sometimes drifts in. The en- trance of rain can be prevented by carrying down the sides of the overhanging ridge for some little distance, and a flange placed a short distance below the opening will throw any down-draft toward the walls. To be of most advantage, the space under the longitudinal ventilating ridge should be contin- uous throughout with the room below. In many instances in our service, foul air can escape from the room into the ven- tilator space only through gratings, the latter catching and retaining much dust and being cleansed with the greatest difficulty. In many instances also, where ridge ventilation has been provided, there is an utter lack of pro- portion between the small gratings in the ceiling and the large apertures in the ventilating ridge. During cold weather ridge ventilators must be closed. All the forms of ventilators above described serve purely as outlets when the windows and doors of the room are open. If these be closed and open fireplaces or stoves are used, the currents may be reversed and the ventilators thus act as intakes only. Fairly good ventilation can be secured by means of a series of horizontal ventilat- ing shafts placed close to the ceiling. These, running across the room from wall to wall, open into the air at each end by a ventilat- ing air brick or register. The sides of these tubes are of perforated zinc and, to prevent the wind blowing directly through, the cen- ter is divided vertically by a partition. According as the wind blows from one side or another, one part of the shaft becomes an inlet and the other an outlet. It is obvious that the different arrange- ments for ventilation described above pos- sess a special value for the military service, since they present no mechani- cal difficulties of construction and may be satisfactorily improvised in an no. 224.— McKlnnell's Circular Ventl- later. 478 THEORY AND PRACTICE OP MILITARY HYGIENE. emergency out of any materials wMch may be at hand. Where troops are placed in temporary and roughly constructed winter-quarters, the establish- ment of simple arrangements of this kind wiU add greatly to the ventila- tion and healthfulness of the latter. Extraction by Heat. — The proper ventilation of barracks is insepa- rably connected with the heating of air. In becoming warmer, air endeav- ors to expand, and if there be any opportunity for it to escape a portion of it wlU do so, and that which remains wUl be lighter than an equal bulk of the colder air outside. The outer air will then flow into the room by every orifice until the equality of weight outside and inside is re-estab- lished. But as the fresh air which comes in is heated in its turn, the movement is kept up in a constant stream, cold air entering by one set of openings and warm air escaping by another. In winter, the artificial warming of barracks greatly assists the change of air within them, as does also the means used for illumination. The amount of heat given off from the bodies of soldiers is also no small factor in raising the temperature of squad-rooms above that of the open air. Putzeys states that about 67 per cent, of the body heat of an individual is ordinarily lost by radiation and contact, and the same writer quotes figures given by Barral to the effect that the heat given off by the body of an adult is capable of raising the temperature of 500 cubic feet of air 27° F. in an hour. This amount of heat given oif by the bodies of soldiers is not only a point to be considered in connection with the necessity for renew- ing the air in barracks, but may thus become a factor of importance in relation to the processes by which this is accomplished. Obviously it is during winter that ventilators have their maximum influence. In summer or in tropical climates the outside temperature is high, and the influence of heat upon the renewal of air in rooms is reduced to the minimum — ^but fortunately under these conditions special methods of ventilation depending upon heat are of less im.portance, since at such times the outside doors and windows are generally kept open. In calculating the rapidity with which ventilating air currents wOl pass in and out of heated barracks, use is generally made of two well- known physical laws : First, that the velocity in feet per second of fall- ing bodies is equal to nearly eight times the square root of the height through which they have fallen; and second, that fluids pass through an orifice in a partition with a velocity equal to that which a body would at- tain in falling through a height equal to the difference in level of the fluid on both sides of the partition. In the consideration of air currents there is substituted for the difference of level the difference in pressure on the two sides of the partition or opening, and this is expressed by the differ- ence in height of the openings of entrance and exit, divided by 491; -^^ representing the expansion of the atmosphere in volume and lessening of density for each degree (Fahrenheit) of rise in temperature. The velocity of influx or outgo will, therefore, equal / (difF. in temp.) x (diff. in height) 491. For determining the velocity of the movement of air up a heat extrac- tion shaft, the following formula is offered by Notter and Firth : V = 36.5 VH(t-T). V^ VENTILATION. 479 In this, V is the velocity in feet per second, H is the height of the shaft in feet, t is the temperature at the top of the shaft, and T is the tem- perature of the air supplying it. The velocity multiplied by the sectional area of the shaft gives the cubical discharge. In practice an allowance must be made for fiiction. Billings places this at from twenty to fifty per cent., so minute calculations are useless. Carpenter gives the following table showing the quantity of air, in cubic feet, discharged per minute through a shaft of which the cross-sec- tional area is one square foot ; the external temperature of air being figured at 32° F., and the allowance for friction being fifty per cent. Under most conditions in the military service the allowance for friction need not be so high, usually not more than twenty-five to thirty-five per cent. Height of flue Elevation op Tempekaturi OF Air in Flue Above that of External Air. in feet. 5". 10°. 15°. 20°. 25°. 30°. J50°. 100°. 1 cubic feet. 24 55 77 94 108 121 133 143 153 162 171 188 cubic teet. 34 76 108 133 153 171 188 203 217 230 242 264 cubic feet. 42 94 133 163 188 210 280 248 265 382 297 335 cubic feet. 48 109 153 188 217 242 265 286 306 335 343 873 cubic feet. 54 131 171 210 242 371 297 320 343 363 383 420 cubic feet. 59 134 188 230 265 297 325 351 375 398 419 461 cubic feet. 76 167 243 297 342 383 419 453 484 514 541 594 cubic feet. 108 5 242 10 15 343 419 20 484 25 541 30 593 35 640 40 684 45 734 50 765 60 835 From this table it is apparent that where the foul air of different floors of a barrack building is removed through heat extraction shafts, the dis- charge of air from the lower rooms, other conditions of size of shafts and temperature being the same, will be much greater than from those of the upper story. It follows also that where a squad-room is ventilated through several up-cast shafts, the length of these, together with their exposure to cooling influences, should be the same. Billings states that the move- ment of air in outlet shafts is normally about five feet per second from lower floors and four feet per second from upper rooms, provided that the flue is not artificially heated above room temperature. It is clear that to secure an equal outflow of air from upper floors there must be a propor- tionate increase in the sectional area of their discharge shafts. These are all practical points which appear to have rarely received consideration in our service. Ordinary chimneys with open fireplaces afford excellent facilities for the extraction of air by heat, the outgoing current of air being proportional to the size of the fire and of the chimney. A small fire is said to give an upward movement of air at the rate of about five feet per second ; a large open fire of eight or nine. "With open fires, aU other openings usually be- come inlets, the movement of the air in the room being toward the fire- place. In the British and other foreign armies, open fires are much used; in our own service they are rarely employed, since they are wasteful of fuel in proportion to the heat they give out into the room. 480 THEOEY AND PEACTICE OF MILITAEY HYGIENE. Fig. 225.— Amott's Valve. Efforts have been made to use the drafts passing up the chimneys, where stoves or furnaces are used, for the aspiration and escape of vitiated air from the room; but with ordinary openings reverse currents, with an influx of smoke and gas into the room, were always to be apprehended. To overcome this fault, valves of some light material, opening only toward the chimney, have been employed. Arnott's valve consists of a light silk curtain which lifts up readily wher^ the movement of air is outward, but is pressed flat against a metal grating by reverse currents and thus closes the opening. With this valve there is sometimes reflux of smoke from the silk curtain not fitting tight- ly. To overcome this defect, Boyle suggested the use of thin mica plates ; and recently plates of aluminum have been employed for the same purpose. It is very evident that such valves will not be lifted by the weaker currents of air, and the snapping noisf they make when closing, especially with metal flaps, is said to be sometimes objectionable. On the whole, however, these valves may at times serve a useful purpose as accessory to other means of venti- lation. Even when they have no fire in them, chimneys may serve as heat ex- traction shafts through the heating of the upper part of the chimney by the sun. To aid in this respect, chimneys may with advantage be painted black to better absorb the solar heat.; and in some cases the roof immedi- ately around the chimneys, together with screens on the northern ex- posure, have been painted white with a view of reflecting additional heat rays upon them. These simple measures may of course be taken to in- crease the efficiency of ordinary up-cast ventilating shafts as well as chim- neys. It should not be forgotten, however, that where these shafts pro- ject much above the roof, they are also exposed to cooling influences which retard the passage of air up them. Wherever the heat in the rooms below is greater than that of the surrounding air, an ascending current through the chimney wiU be established ; while if the temperature of the air in the chimney be from any cause lower than that of the surrounding air a reverse current is established. While affording valuable assistance in ventilation, chimneys and open fireplaces are not sufficient for the proper renewal of air in lar_ge and crowded rooms, as in barracks, and additional measures should be pro- vided where they are used. As previously mentioned, the temperature of ex- tracting shafts is usually maintained at a sufficiently high level, where stoves are employed for warming, by passing the stove pipes up through the shafts before discharging into the chimney or outer air. This utilizes much of the heat which might otherwise be lost. Where steam heat or hot water is used for warming barracks, the pipes may be coiled around the lower part of the ventilating shaft to maintain it at the desired temperature. In some of our new barracks, heated in this man- ner, this method is not used ; it being claimed that sufficiently good results are obtained by building the ventilating up-cast shafts in the masonry of Fig. 226.— Boyle's Valve. Back view. VENTILATION. 481 the chimney, and utilizmg such heat as may be conducted through the walls of the latter. This method, though valuable, can obviously be im- proved upon. All methods of ventilation by extraction by heat are unsatis- factory unless a sufficiently elevated temperature is maintained ia the flues ; though usually when no fires are kept up the outside temperature is such that recourse can be had to natural renewal of air by open windows and doors. There are occasions, however, when such arrangements are un- satisfactory ; and imder such conditions lamps or gas-jets may be used to heat the shaft and promote up-currents. The burners should be lo- cated at the bottom of the shafts to give the maximum results. The re- lation between the amount of coal-gas bm'ned and the volume of air removed is variable ; Morin having shown that it was much more economical to dis- tribute the heat in a flue with a large sectional area than to bum the same amount of gas in a small shaft. Notter and Firth state that one cubic foot of gas burned is capable of extracting 3,000 cubic feet of air, under favorable conditions ; while Laveran places the average amount which can in practice be removed at 2,500 cubic feet. Instead of burning the gas or oil directly in the shaft, the lower part of the latter can be made of sheet metal, the flame being maintained beneath this metal frame, as shown in Fig. 227. As mentioned elsewhere, it is extremely important that the heat resulting from illumination should be uti- lized for room ventilation, the same means removing the heat and the impurities resulting from combustion. The latter may be collected in a funnel over the lamp or gas- jet, and can be conducted outside by an extracting shaft, together with much of the heated and impm-e air of the room itself. The Wenham recuperative burner, described in the section on the lighting of barracks, is of excellent service in promoting ventilation. Wherever shafts are used for the extraction of air by heat, it is obvious that they should be enclosed within walls as much as possible to prevent the contained air from being cooled. This simple point has sometimes been overlooked, and the efficiency of up-cast shafts thus practically de- stroyed. Where central heating is employed, the ventilating shafts are best placed between partition walls ; since if they are located in outer walls a certain amount of chilling is unavoidable. Where stoves are used in pavilion barracks or wards, the extracting shafts are best placed in the center of the room with respect to the prevention of chilling — ^though when so placed they are somewhat inconvenient for purposes of administration. Extracting shafts should be as straight as possible and possess smooth in- terior surfaces, so that friction should be reduced to the minimum. They are best made cylindrical for the same reason; and should be capped with cowls to aid the aspiratory action of the wind, reduce the liability of down- drafts and prevent the entrance of rain, which, by its evaporation, would tend to lower the temperature of the shaft and interfere with its operation. Sometimes, also, the heated air becomes cooled by passage through an ex- posed tube, as already suggested, so that it cannot overcome the weight of the superimposed atmosphere ; or another outlet shaft of greater discharge may reverse the current. This possible reversion of action in outlet tubes is a reason why proper attention should be given to their cleanliness. 31 482 THEOKY AND PEACTICE OF MILITAEY HYGIENE. FIG. 328.— Rotating Cowl for Aspira- tion. Ventilation by Aspiration. — The action of winds is of considerable value iu securing the proper renewal of air iu barracks. A moving body of air sets in motion all air m its vicinity. It drives air before it and, at the same time, causes a partial vacuum on either side of its own path, toward which aU the air in the vicinity flows at angles more or less approaching right angles. In this way a small current moving at a high velocity wUl set in motion a large body of air. Advantage can be taken of this as- piratory power of the wind to cause a movement of air up an ordinary shaft; the rapidity of the ascending cur- rent being in direct relation to the horizontal velocity of the wind. The latter, however, in the absence of pro- per means of protecting the top of the shaft, may at times impede ventilation by obstructing the exit of air from any particular open- ing, or by blowing down a chimney or tube. This is, in fact, one reason for the failure of so many of the less carefully planned systems of ventila- tion; they may work well in a fairly stiH atmosphere, but the immense resistance of high winds has not been taken into account. The aspiratory power of the wind and the production of a head for ventilation, by the movement of air over the mouth of a tube, can best be secured by covering the air-shaft with a cowl, which both aids up-currents and prevents down-drafts. This is practically the idea with which all varieties of up-cast ventilators are constructed, however varied may be their external appearance. As usu- ally fixed to buildings, cowls may be uncertain in their action from the variability of the wind cur- rents, due to the effects of the surfaces of the buiLdiags themselves. Although many forms of cowl have been designed to render up-cast ventila- tors serviceable, irrespective of the direction from which the wind blows, there are practically only two types; namely, those with rotating cowls and those with fixed vanes. Of the former type the simplest form is shown in the accompanying illustration (Fig. 228), it setting itself by means of a wind-vane so that the opening always faces away from the wind. An improvement on this primitive type is Banner's cowl, which probably represents the best form of rotating aspiratory ventilator. In winter, how- ever, this apparatus is said to be liable to be stopped up with snow. In general, all rotating cowls are very efficient so long as they act as intended ; but they are apt to become fixed and have their action reversed by winds from the opposite direction. When rusty, their movement is accompanied by an unpleasant grating noise, but on the whole they are satisfactory. The fixed type of exhaust apparatus is best repre- sented by the Star ventilator, now being used in our service to the exclusion of other models. In it the motion of air is always tangential to the shaft opening, from whatever di- rection the wind blows. This ventilator is very efficient as regards as- Fis. 229.— Banner's Rotating Exhaust Ventilator. Fig. 230.— star Ventila- tor. VENTILATION. 483 Fig. 231. — Wolpert's Ventilator. piration, is protected against raia and down-drafts and does not collect snow and ice ia winter. Somewhat similar ia principle to this, but less efficient, is the Wolpert ventilator, much used in foreign services. This consists merely of a pipe supporting an aspiratory chamber flaring at the bottom and with a protective cap fastened a couple of inches above its upper margin. Down-drafts are effectually prevent- ed with this apparatus, but its aspiratory effect is by no means as great as is given by the Star ventilator. A third modification of the fixed ventilator is the Hanks apparatus. This is an excellent ventilator having a powerful exhausting effect, the large amoimt of wind brought to act on the orifice of the inner pipe having great extracting power even in a gentle breeze. A cap to protect against storm-water and minimize down- drafts is generally used with this ventilator. A com- mon modification of an ordinary up-cast shaft, and one which gives fairly good results, consists in adding a simple flange which slopes downward and outward from the rim of the tube. This increases aspiration by giving an upward tendency to horizontal air currents. A conical roof keeps out rain and prevents down-drafts. From the simple construction of aspirating cowls it is evident that, in an emergency, excellent makeshifts can readily be improvised from a few joints of stove pipe and such sheet metal as can readily be obtained from old coal-oil cans or water buckets. It having been found that where a number of small separate flues lead from a single room they are liable to pull against each other, it will frequently be of advantage to bring several of such flues together to a single outlet, protected by a suitable ventilating cowl. Other Means of Ventilation. — The renewal of air by means of fans is accomplished by either extrac- tion or propulsion. The latter method is usually pre- ferable, since the entering air may be drawn from a source known to be pure, and may be heated or cooled before being passed into the apartment. By this means fresh air can be distributed with ease and certainty at any rate and in any quantity. The disadvantages are great cost of operation and the constant possibility of break- ing down at the time when most required. On account of the expense attached to its operation this method of ventilation is not suited to barracks, though well adapted to hospitals. Several hospitals in the French military service are ventilated in this manner; the movement of the fan, in one case, changing its direction every half hour, forcing air in and drawing it out alternately. The system of ventilation by propulsion has been tried in our fig. 233. _ Tube service, having been installed at Madison Barracks a num- Si-'As^iraHoa"^' Fig. 232.— HanSs's Ven tilatoT. 484 THEORY AND PEACTICE 0¥ MILITAEY HYGIENE. Fig. 234.— wing Disc Fan. ber of years ago. The results given by it as regards the renewal of air were reported as excellent ; but motives of economy later resulted in its dis- use, and other methods of ventilation have been substituted for it. Either steam or electricity may be used for power. The chief fans used for this method of ventilation are the Blackman air propeller and the Wing circular fan. The larger siiies of the Blackman fans are said to give 12,000 cubic feet of air per minute, and the smaller sizes 6,000 cubic feet, per horse- power. This estimate is based on the supposition that there is no resistance against the air save from the machine itself. In practice there is much friction, with resulting loss. The Wing disc fan has been much used for building ventilation. A four- foot fan is stated to move 500,000 cubic feet of air per hour, using one horse-power. The best fans for use are those of large size, since with them there is less noise and wear as the result of operation. Steam jets have been used for the production of air currents in dis- charge ventilating shafts. They are obviously available only where an abundance of steam is at hand, and possess no advantages for the ventila- tion of barracks. They have been much used on the troop-ships of the British service. Their use is confined to extraction, in which they are very efficient. The cone of steam is said to, set in motion a column of air equal to 217 times its own bulli, and some of the larger sizes of apparatus wOl extract 100,000 cubic feet of air per hour. The principle of the ap- paratus is very simple, as is shown in the accompanying illustration (Fig. 236). During the last few years, hydraulic venti- lators have been constructed by which, irre- spective of atmospheric conditions, the move- ment of large quantities of air is accomplished by means of water sprayed \mder high pressure. These hydraulic ventilators are said to be much used in Germany and to be in operation in some of the barracks of that country. For their use an abundant supply of water under consider- able pressure is necessary. They are said to be not costly in operation and to be capable of supplying 70,000 cubic feet of air per hour. They consist merely of U-shaped pipes con- taining spray nozzles. The air is sucked in and passed forward by the falling spray, while the water collects in the bottom and is discharged through a pipe at the lowest point. Being provided with a spray nozzle I Fig. 235.— Blackman Wheel. VENTILATION. 485 Fig. 236.— steam-Jet Ventilator. in each shaft, the apparatus is capable of ventilating either by propulsion or aspiration. Certain forms are made for hospitals which, in warm weather, may be readily disconnected with the outside air and the air in the room passed through them, thus materially lowering its temperature. The apparatus clearly cannot be used ia cold weather and its proper operation is said to be interfered with by the use of muddy water. It has little value for the military service. Examination of Ventilation. — Since the sanitary officer may be required to report upon the sufficiency of an existing system of ventila- tion, it is important to consider briefly the best means for arriving at conclusions in this respect. In an occupied room, a determination of the proportion of carbon dioxide present is chiefly relied upon in deciding as to the efficiency of ventilation. The results given by this method, as subsequently detailed, are conclusive. Where a room is not occupied, the most reliable means for determining the sufficiency of ventilation is based upon the fact that if in a closed room there be generated any easily recognizable gas, as car- bon dioxide, the amount of fresh air entering in a given time may be de- termined from the dilution experienced by the gas during this time, not only by the exchange of air through the ventilators but also through cracks and crevices. Tor the generation of the carbon dioxide, Pettenkofer re- commends the burning of stearine candles of good quality ; such candles giving o£f about 2.764 grams, or 1.404 liters, of CO^ per gram of stear- ine burned. After the combustion of a num- ber of these candles in the room, with its ven- tilators and doors closed, a chemical analysis of the air, taken from the centre of the room by a rubber pipe, is made. The ventilators are then opened, and two determinations of the carbon dioxide made at intervals of thirty minutes. Since in the military service the chemical analysis of air may not always be practicable, recourse may be had to the sense of smeU, which, under such conditions, wiU. furnish a useful and ready means of estimating the sufficiency of ven- tilation ; since it has been shown that the amoimts of mal-odorous organic respiratory impurities and of carbon dioxide present have, within certain limits, a definite relation to each other. The re- sults obtained are of course not exact and vary to some extent with the observer, but they are suffi- ciently accurate to be of much practical value. The test is best carried out in barracks at the period of greatest respiratory impurity, or shortly be- fore reveiUe. The air-space should be entered directly from the external Fig. 237.— Water-Spray Ventilar tor. 486 THEORY AND PEACTICE OF MILITARY HYGIENE. air, or as near so as possible, since the sense of smell is rapidly impaired in vitiated air. In a large number of tests made by de Chaumont to deter- mine the value of this process, the amount of carbon dioxide was found by chemical analysis at the same time, so that the existing respiratory im- purity was accurately known. On dividing his observations into groups, the following results were obtained : Fresh, or not differing sensibly from the outer air. Rather close ; organic matter be- coming perceptible. Close; organic matter disagreeable. Very close, organic matter offensive and oppressiye; limit ot differentiation by the sense ol smell. Mean CO2 per 1,000 vols., re ducedto33'F., due to resplra tory impurity alone. 0.1943 0.4133 0.6708 0.9054 From this it is apparent that the odor of organic matter is, on an aver- age, imperceptible to the sense of smell when the coincident CO^, due to respiratory impurity, does not exceed 0.1943 per 1,000; and that when it reaches 0.9054, the olfactories are no longer able to detect grades of dif- ference. In roimd numbers, 0.2 per 1,000 may therefore be taken as the maximum amount of respiratory impurity as regards carbon dioxide — or 0.6 per 1,000 when added to the carbon dioxide normally present in the air — admissible ia a properly ventilated space. This relation between air vitiation and the odor to which it gives rise in an occupied room varies to some extent with the temperature and the amount of moisture present; under some circumstances the odor due to organic contamination from res- piration may not be perceptible until the carbon dioxide exceeds 0.3 parts per thousand. By bearing the above figures in mind an approximation of the amount of respiratory impurity in a squad-room may be made. The sufficiency of ventilation may also be estimated by determining the amount of air which passes in and out of a room, its floor space and cubic contents, the number of persons to be supplied with fresh air, to- gether with the direction and velocity of air currents within the room and their effect upon the occupants. If there are distiact and special outlets, as by flues provided for the purpose, it wiU generally suffice to measure the amount of the air passiag through them, since the quantity of iacom- ing air wiU be nearly the same. The quantity of the air passing through these outlets is readily found by multiplying the area of the opening, stated in square feet, by the velocity of the current of air expressed iu liaeal feet per minute. The product is the delivery of air in cubic feet per miaute. Since the rapidity of the air current is very variable, depending upon wiad, difference in temperature and other factors, it is evident that a fair average should be made from a number of observations before arriving at definite conclusions. The velocity of the air current is determined by the anemometer, an instrument so constructed that the velocity of moving air is shown by the rate at which it causes a light propeller-like wheel to revolve when placed in its course. The number of revolutions are recorded, in feet or meters, on a fixed dial with which the wheel is connected by VENTILATION. 487 an arrangement of cogs, and may be read off at suitable intervals, usually of exactly one minute. A catch is placed on the rim of the instrument to enable the observer to throw the indicating wheels in or out of gear from the fan, for the purpose of taking short observations with accuracy. In using the apparatus, care should be taken that the air current strikes the fan at right angles with its plane ; the instrument being allowed to run for a minute before readings are begun. AU these instruments present a cer- tain amount of friction, for which a slight correction must be made. Since the rate of movement of air currents passing through an opening may vary considerably, it is customary to make five readings for each aperture, a t different points, and accept the general average as the mean rate of velocity for the whole. As aheady noted, in calculating the flow of air through an or- dinary register a deduc- tion of about three-tenths must be made for the grating. Laveran states that the inclination of a can- dle flame at an angle of 45°, when placed in a draft, shows the pres- ence of an air current having a rate of 0.4 to 0.5 meters per second. This method may be used for estimating the velocity of air currents when no more exact means are available. When direct measurement of incoming and outgoing air currents is made the results obtained can be considered as only relatively accurate, because of an indefinite but considerable amount of leakage of air around doors and windows. To determine the direction of air currents within the room, smoke is commonly used. This may be produced by burning tobacco, cotton vel- vet or a lamp-wick saturated with benzoin. The fumes of nascent am- monium chloride are in some respects preferable to smoke, since they are of the same temperature as the air. They are produced by pouring a little ammonium hydrate into a capsule, and suiroimding this with a sheet of blotting paper pinned in the shape of a cylinder and saturated with dilute hydrochloric acid. Sometimes feather-dust is used to demonstrate air cur- rents ; and filaments of floss silk suspended from a rod or from the ceiling furnish a delicate test for the same object. Unless an air current be very weak it, and its direction, may be detected by the moistened finger, through the sensation of cold imparted. Fig. 238.— Anemometer. 488 THEORY AND PRACTICE OF MILITARY HYGIENE. EXAMINATION OF AIR. For hygienic purposes, ia the practical examination of air in the mili- tary service, the chief points requiring attention are the manner of coUect- iQg the sample and the estimation of the amount of carbon dioxide pres- ent. The latter is done roughly by means of the senses, as already described, but much more exactly by chemical procedures. There are other subjects which are sometimes given consideration in connection with the examination of air, such as the determination of the oxidizable and organic matter, the estimation of carbon monoxide, the presence of ozone, the determiaation of aqueous vapor and an examination of the suspended matter and micro-organisms, but' these are not of sufficient practical im- portance to warrant their beiag included in a work of this special character. AH air samples should be collected at a time when the pollution of the atmosphere is the greatest, which, in the case of a squad-room, is shortly before reveiUe. For the actual collection of the samples, large rubber- stoppered jars, holding from five to ten liters, are the most convenient. These are thoroughly cleansed with distilled water before use, inverted to run dry, and stoppered — a label being attached for stating the current temperature and pressure. To fill the jar with the air sample the simplest way is to fill it to the brim with distilled water, invert it and allow it to drain dry in the room, the air of which it is desired to collect. As the water flows out of the jar, air rushes in to take its place. Since water, however, may hold a considerable quantity of carbon dioxide in solution, and since it is scarcely possible to remove at once all moisture from the interior of the collecting jar when the above procedure is employed, many chemists prefer to • avoid possible sources of error and to pump the air sample into the jar by a small syringe, the nozzle of which is passed to the bottom of the receptacle so as to displace the contained air upward. At the Army Medical School, before collecting the air sample, the student offi- cers are required to wash the jar with distilled water, to remove aU moist- ure from the jar with alcohol, to remove the alcohol with ether, and finally to remove the ether by vigorous pumping with the air syringe. After filling the vessel, it is at once closed with an air-tight stopper or rubber cap ; care being taken that no breath is introduced into the jar before it is stoppered. After stoppering, the label is inscribed with the ciurrent temperature, barometric pressure and the cubical capacity of the jar. The most common and generally satisfactory procedure for the estima- tion of carbon dioxide is Pettenkofer's alkalimetric method. This depends upon the fact that clear lime-water or baryta-water, both of which are strongly alkaline media, will readily absorb and neutralize carbon dioxide ; the absorption of this weak acid diminishing by so much the allvalinity of these media. If, therefore, the degree of alkalinity of either of these solu- tions be known both before and after exposure to the carbon dioxide, the difference will represent the amount of CO, which has combined with the lime or baryta in the formation of a carbonate. The practical details of the process are given by Smart as follows : An oxalic acid solution is made by dissolving 2.864 gm. of the acid in one liter of distilled water, 1 c.c. of this solution being equivalent to 1 VENTILATION. 489 mgm. of CO,. A caustic baryta or Lime solution, of equivalent strength, is then made up. This alkaline solution is stored until required for use iu small bottles, holding about 60 c.c. each. The latter are then tightly corked, weighed, and the weight of each filled bottle is marked on its label. The air sample having been collected in a suitable container, the contents of one of the lime or baryta-water bottles is poured into the collected air, and the container is closed with a rubber cork or carefully ground stopper. The temperatures by the wet and dry bulb thermometers and the barometric pressure are observed, and are marked on the jar containing the air sample. The air container is then shaken and allowed to stand until the following day, if lime is used; or with baryta- water it is shaken and revolved for fifteen minutes, at the end of which time the formation of barium carbon- ate may be considered to be effected. The quantity of baryta solution in- troduced into the air container is obtained by re-corking and weighing the bottle in which it was stored, and deducting this weight from the gross weight marked on the label. The loss of weight in grams equals the number of cubic centimeters of the baryta or lime solution transferred to the bottle containing the air sample. This number of cubic centimeters must then be deducted from the known capacity of the jar. But in order that the experimental results may be susceptible of com- parison, it is necessary to express the air volume in the space which it would occupy when dry at 0° C. and under a pressure of 760 millimeters of mercury. Increased pressure diminishes the volume of air, while in- creased temperature expands it ; and the pressure of the wg,tery vapor present must also be taken into account. The temperature observations furnish the dew point, and through it, from the observations of Eegnault, the pressure or tension of the aqueous vapor may be obtained. If p represents this pressure, t the temperature in Centigrade degrees, h the barometric height in millimeters and V the capacity of the jar, minus the number of cubic centimeters of baryta solution introduced, the corrected volume wiU be equal to — V (b-p) 273 (273-f 760 If the observations have been made on the Fahrenheit scale and in barometric inches, the formula is — V {l-p) 491 29.92 (491+c^O in which dt is the number of degrees between 32° F. and the observed temperature. To test the causticity of the baryta water after being shaken with the air sample, 20 c.c. are removed from the jar, phenolphthalein solution added to it in a beaker and the oxalic acid solution slowly titrated in from a burette until the red color is discharged. The loss of alkalinity in cubic centimeters equals the number of milligrams of CO^ in the 20 c.c. of the solution tested; from which the CO^ absorbed by the whole of the baryta solution may be calculated, equalling the same number of milli- grams of COj in the sample of air collected. The weight of the CO, is then converted into volume by multiplying by 0.573, and for purposes of 490 THEOEY AISTD PRACTICE OE MILITAEY HYGIENE. comparison it is calculated into volumes per 10,000 of the corrected air. It must be mentioned, however, that the volume of carbon dioxide found by this process is not all carbonic impurity, but includes also that naturally present in the atmosphere. When the result of a contemporaneous analy- sis of the external air has been deducted from it, the remainder will indi- cate the carbonic impurity due to imperfect ventilation. For general military purposes a convenient method for estimating the amount of carbon dioxide present is that proposed by Smith; for which there will be needed six well-stoppered bottles, containing respectively 450, 350, 300, 250, 200 and 100 c.c, a glass pipette graduated to contain 15 c.c, and a bottle of perfectly clear and transparent fresh lime-water. The bottles should be thoroughly clean and dry. Having pumped the bottles full of the air to be examiued, by means of a small bulb syriage, 15 c.c. of the lime-water are placed in the smallest bottle by means of the pipette ; the bottle being tightly stoppered and the whole vigorously shaken. If the lime-water presents a turbidity, the amount of carbon dioxide present wiH be at least 16 parts in 10,000. If no turbidity appears, the next sized bottle — of 200 c.c. capacity — is treated iu like manner. Turbidity in this would indicate 12 parts of carbon dioxide iu the ten thousand. If this remaius clear, but turbidity is produced in the 250 c.c. bottle, it marks about 10 parts per 10,000. The 300 c.c. bottle indicates 8 parts, the one of 350 shows 7 parts and the one of 450 less than 6 parts per 10,000. To judge of the turbidity, a small piece of paper is marked with a cross in lead pencil, and gummed with its face to the side of the bottle on the lower part. When the water becomes turbid, the cross wiR be invisible when looked at through the water. This test is so readily carried out as to be specially adapted to the needs of the military sanitarian. CHAPTER XI. HEATING AND LIGHTING. I. HEATING. General Considerations. — Heat is required to maiataia the air of barracks at a suitable temperature, to make good tbe loss of heat due to its radiation and conduction from windows and walls, and to supply warmth to the air required for ventilation. The amount of heat necessary for these various purposes wiU depend largely upon the outside tempera- ture, the construction of the buLlding and its exposure, and the supply of air needed for the maintenance of proper ventilation. The warming of barracks is not satisfactorily accomplished unless the temperature is suffi- cient and is uniform for time and space ; the physical properties of the air, especially its moisture, are maintained; the atmosphere is not vitiated by the products of combustion or by dust; and unless the heat contributes to the accomplishment of ventilation. In addition, the apparatus for the generation and distribution of heat should be simple in construction, eco- nomical of fuel and labor in its operation, and be free from the dangers of fire or explosion. The heat evolved in the combustion of fuel is given off to surrounding bodies by conduction, by radiation and by convection. Conducted heat passes from one particle of matter when they touch, or are separated only by insensible distances. Heat is conducted through aU solids, which vary greatly in their conductivity, but is transmitted only to a very limited de- gree by liquids and gases. Thus the conducting power of copper in re- spect to heat is given as 20,150 times greater than that of air, and 554.1 times greater than that of water. Bodies which are good conductors rap- idly give off their heat to the surrounding air or to anything in contact with them, and in like maimer, if colder, they withdraw heat from other bodies . Eadiation is not only the most common but also the most wasteful of the ways by which heat is distributed. Eadiated heat is propagated from its source in straight lines and with equal intensity; the effect decreasing according to the square of the distance. Radiant heat is reflected like light from solid bodies, but some of the heat is absorbed ; the amounts re- flected and absorbed being in inverse proportion to each other, and largely dependent upon the surface, color and nature of the object, as well as upon the difference of temperature between the receiving and radiating bodies. The convection of heat is that mode by which heat is chiefly propagated in liquids and gases, and is dependent on the characteristic of those bodies by which such portions of them as have become heated expand and rise, 492 THEORY AND PRACTICE OF MILITARY HYGIENE. their place being at once taken by the colder parts. A species of circula- tion is thus established and the whole mass of liquid or gas is soon ■warmed. Every person in a room causes convection currents by the heat conducted to the air in contact with his skiu or clothing; while the air of a heated room, from a similar cause, is in a state of active movement. The convection currents produced by fires, and by the human body in an atmosphere colder than itself, not only carry off some heat but also provide the body with a supply of fresh air. When the temperature of the sur- rounding air is nearly that of the body, this natural replacement of air does not occur ; requiring the production of artificial air-currents for comfort. An idea of the relative efficiency of radiation and convection, iu the accom- plishment of heating, may be gained by placing the hand alongside a lamp flame and then above it; this simple test readily showing that far less heat is lost by radiation than is carried away by ascending aic-currents. This explains the deficient heating qualities of the ordinary open fireplace ; since only radiated heat is utilized by this means, while the air heated by the fire passes up through the chimney and escapes from the buUding. The sensations produced by radiated and convected heat are also quite different; radiant heat warming only the side exposed to the source of heat, while the air warmed by convected heat has an equal effect on all sides. The heating of a room is technically said to be effected by direct radi- ation, by indirect radiation, by direct-indirect radiation, or by combina- tions of these methods. In this sense, direct radiation means that the heating surfaces are placed in the room to be warmed and are not con- nected with the air supply, so that the incoming air is not warmed. This method is clearly not satisfactory. Indirect radiation means that the room is heated by air which has been warmed by being brought into contact with heated surfaces placed in some, other room, usually in the basement or cellar. Direct-indirect radiation means that the heating siu-faces are in the room to be warmed, and have outside fresh air brought around them to be raised to the desired temperature. At present, in our new barracks, heating by direct-indirect radiation is the method usually employed. Whatever be the special method of heating adopted, it is obviously desir- able that the warming of air in a room should be accomplished at its cold- est point. In practice, the problems of ventilation are very closely connected with those of heating ; since heat is one of the important agents in accomplish- ing ventilation, and the distribution of heat is commonly dependent upon the distribution of heated air or water. All waste heat should be utilized in securing a proper renewal of air ; and thus, even in hot weather, a little ingenuity may convert heat, generally so annoying, into a valuable power for cooling down the an of a buildiag. The combined action of heat and air-currents is of much importance in maintaining the proper dryness of habitations. The unit of measure of heat commonly employed in this country is Imown as the British heat unit, and is that quantity required to raise one pound of water one degree Fahrenheit ; another unit of measure is the Calorie, representing the amount of heat required to raise one kilogram of water one degree Centigrade. It is sometimes convenient, in ventilation HEATING AND LIGHTmG. 493 and heating problems, to express the amount of heat in terms of force. When so expressed, the British thermal unit is equal to 772 foot-pound-s of force, and the Calorie is equal to 423.985 kilogram-meters; each kilo- gram-meter being equal to 7.2 foot-pounds and one Calorie being equal to 3.968 Fahrenheit units. The calorific power of any combustible is repre- sented by the number of heat units (or Calories) which one pound (or kilo- gram) is capable of developing on being burned. Assuming that the volume of air is constant, the foUowing table from Billings shows the number of thermal units required to heat a given volume of dry air a cer- tain number of degrees Fahrenheit, commencing at 32° F. Cubic feet. Heated. P. 2°. 3°. i". 5°. 6°. 7°. s°. 9°. 100 1.92 3.84 5.76 7.68 9.60 11.52 13.44 15.36 17.28 3.84 7.68 11.52 15.36 19.20 23.00 26.88 30.72 34.56 5.76 11.53 17.28 23.04 28.80 34.56 40.32 46.08 51.84 7.68 15.36 23.04 30.72 38.40 46.08 53.76 61.44 69.12 9.60 19.20 28.80 38.40 48.00 57.60 67.20 76.80 86.40 11.52 23.04 34.56 46.08 57.60 69.12 80.64 92.16 103.68 13.44 26.88 40.32 53.76 67.20 80.64 94.08 107.52 120.96 15.36 30.72 46.08 61.44 76.80 92.16 107.52 123.88 138.24 17 28 200 34 56 300 51 84 400 69.12 500 86 40 600 103.68 700 120 96 800 188.24 900 155.52 From this table it is easy to calculate the amount of heat in thermal units required to raise the temperature of any given volume of air through any number of degrees of temperature. The freer the ventilation, the greater the amount of heat which natur- ally must be supplied to maintain the desired degree of warmth. A com- mon method of determining the number of heat units required for ventila- tion consists in multiplying the number of cubic feet of air required during a given time by the difference in temperature between the warm and out- side air, and then dividing by 55. This last number is used as a divisor, since in absorbing one heat unit 55 cubic feet of air will be warmed 1° F. ; and thus this quantity of air may be considered as equivalent to a pound of water as far as the transmission of heat is concerned. The heat capable of being stored or retained in a substance is called its specific heat, and this quality of holding heat becomes of material importance in connection with the warming of buildings. This specific heat is usually described as being the units required to raise the temperature of one pound of the substance under consideration through 1° F. Thus one pound of water requires one British thermal unit to raise its temperature 1° F. ; a pound of steam re- quires 0.480 of a thermal imit; a poimd of expanding air requires 0.238; and air having a constant volume requires 0.169. Weight for weight, water is thus seen to absorb more heat from the same rise of temperature than any other substance ; and hence the economy in the use of water as a carrier of heat, as compared with air, is evident. The loss of heat from buildings, irrespective of that naturally depend- ing on ventilation, is often very great and should properly be anticipated in the establishment of heating arrangements. The determination in ad- vance of the loss of heat through the walls and windows of any given 494 THEORY AND PEACTICE OF MILITARY HYGIENE. building or room is, however, a problem practically impossible of theoretical solution. Clearly no exact figures or rules can be given on this poiut; for the loss of heat from a barrack depends, among other factors, upon the kind of material used in its construction ; the thickness of the walls, and whether they are single or double; the quality of the workmanship; the number and si^e of windows ; and the orientation of the building and its exposure to prevailing winds. Eeliable conclusions as to the probable loss of heat can be arrived at only by the proper consideration of all the factors in the case, fortified by knowledge born of long experience. In all build- ings there is a considerable loss of heat from the crevices around windows and doors, and in limiting loss in this manner weather-strips should always be used on barracks in cold climates. These weather-strips generally consist of slips of metal embracing a narrow band of rubber ; but sometimes strips of wood bordered with closely woven felt are used. These strips are nailed on all sides of the window-iiame, making tight joints against the sashes. In bitter cold weather, when a high wind fairly blows the heated air out of barracks, these contrivances prevent such action to so great an extent that rooms otherwise uninhabitable become warm and comfortable. Eefer- ence has already been made to the great diminution in the loss of heat which results from the use of double window sashes. Although a matter of much importance, the equable distribution of heat through a closed space, together with the maintenance of a proper temperature over considerable periods, is not readily accomplished. This is particularly the case when the external temperature is constantly vary- ing, the barracks are of a poor construction, the rooms have high ceilings and stoves or open fireplaces are used. Heating by hot-air furnaces gives better results ; but the entering warm air tends to rise, and thus forms a series of layers of air increasing in temperature toward the ceiling. With poor floors, this upward movement of heated air causes a great difference in the temperature at the floor and ceiling; and it has aheady been men- tioned that at one northern station a variation of 30° F. was noted between the temperature taken at the floor level and at a point six feet above it. Under such conditions the feet and legs are kept constantly cold by chill- ing air-currents. Undoubtedly the best plan of heating a squad-room so as to secure equability of temperature is by the direct-indirect niethod; the radiators being placed around the room under the windows, which are the points of greatest diathermancy. It is especially important that hos- pitals and guard-houses be evenly heated throughout, since it is plain that patients or prisoners will rarely be able to leave their beds or cells to get nearer to the sources of warmth. An equable temperature extending over considerable periods, however, is obviously unnecessary in places used inter- mittently, as drill halls. Such places are generally warmed up immediately before they are used, and the fires subsequently allowed to die down. There is some economy in this; but the saving is not so great as at first thought might be supposed, from the necessity of overcoming the chilling which takes place between periods of heating. In this connection it is interesting to note that in the French army, on account of the scanty supply of fuel allowed, certain fires are not maintained in barracks throughout the night, but are carefully extinguished except in the coldest weather. The temperature of barracks is best maintained at 66°-68° F. Billings HEATING AND LIGHTING. 495 suggests a temperature of 70° F. ; but this is slightly higher than is neces- sary for the comfort of troops and is more applicable to hospitals. The temperature in gymnasia and drill-halls need not be above 45° F. Sol- diers will not stay in barracks any longer than necessary if these be not sufficiently heated, but will seek resorts where there is plenty of warmth — and such resorts, if outside the garrison, may not be elevatiag in their in- fluences. Guard-houses require to be particularly well heated, so that sol- diers returning from tours of sentry duty may be able quickly to dry out their wet garments and warm their chilled members. On the other hand, over-heating of squad-rooms is always to be avoided. Soldiers are prone to allow this, particularly colored troops, and when coming from over-heated rooms into the cold outside air they are liable to become chiUed, with re- sulting congestive disturbances. Hence the temperature of the squad-room should be regulated by the thermometer and not by the preferences of its inmates; and constant oversight, in this respect, should be had by non- commissioned officers. Kitchens are partricularly apt to become over- heated, and the men employed therein are exposed to frequent and extreme changes of temperature. To limit over-heating, a hood should always be constructed over the range, having a ventilating flue discharging directly into the open air and thus carrying away the heat. This arrangement also serves an excellent purpose in getting rid of cooking odors, without their being carried on outgoing air-currents to be distributed all over the build- ing. Where such an arrangement is used, the flow of air is directed from the building into the kitchen instead of out of it. Air usually contains a considerable amount of moisture; its capacity for taking up auch moisture increasing as its temperature is elevated. Coulier states that a cubic meter of air, under a pressure of 760 milli- meters of mercury, is saturated with watery vapor at 10° C. when holding in suspension 9.7 grams of water; while at 25° C. it would require 22.5 grams to effect saturation. Hence cold outside air which has been warmed and admitted into barracks is deficient in moisture, and this must be arti- ficially supplied. Should this be not done, the undue dryness of the air causes harshness of the skin, irritation of the air passages, thirst and dry- ness of the throat and fauces. With such air there also appears to be a tendency toward the occurrence of tonsillitis. That all these conditions are entirely due to over-dryness of the air there is some doubt; probably the symptoms of irritation of the respiratory tract are dependent more upon the fine dust, largely composed of minute fragments of dry wood ground from the floor by the feet of passers, which acts mechanically as an irritant to the mucous membranes, and which is much less liable to be taken up by moist air. It is generally accepted that where a considerable number of persons are living together, the amount of moisture directly provided should be about fifty per cent., since the human body itself gives off much watery vapor. De Chaumont recommends, for squad-rooms, that the dif- ference between the readings of the wet and dry-bulb thermometers should not be less than four nor more than five degrees Fahrenheit. To supply the necessary moisture, with steam-heat a little watery vapor may be allowed to escape into the air of the room. Furnaces are apt to deliver their hot. air ia too dry a state, and the condition of their evaporating pans, as to a supply of water, should be closely attended to. Where heating 496 THEOEY AND PRACTICE OE MILITARY HYGIENE. stoves are used, a flat dish of water is usually set upon them; but no pro- vision of this character is made in the barrack stoves of the models chiefly furnished ia our service. Too great moisture in the air of a heated room is productive of much discomfort, since it interferes with the proper re- moval of body moisture by respiration and cutaneous evaporation. Fuel. — The production of heat for the purpose of warming and venti- lating buildings is commonly effected by the combustion of fuel. The chief constituents of fuel are carbon and hydrogen, with various chemical combinations of these two elements, whUe their principal products of com- bustion are CO, and H^O. The amount of heat produced in the combus- tion of a fuel is approximately the sum of the quantities of heat which the hydrogen and carbon contained in it would produce separately by their com- bustion. When hydrogen and oxygen exist in a compound in the proper proportion to form water, these constituents have no effect on the total heat of combustion, and it is only the surplus of hydrogen above that which is required by the oxygen which is taken into account. The heat of combustion for one pound of pure carbon is given by Notter and Firth as 14,500 British heat units, and that of one pound of pure hydrogen as 62,032. From these principles and data is deduced the following general formula for the total heat of combustion of any compound, of which the principal constituents, carbon, hydrogen and oxygen, are known : h = 14,500 ]C + 4.28 (H - 0) [ in which Ti is the total heat of one pound of the compound in British thermal units ; C, H and are the fractions of one pound of the compound consisting respectively of carbon, hydrogen and oxygen, while 4.28 is a constant deduced from the ratio of 14,500 to 62,032. To calculate the quantity of air required for the combustion of any given fuel, the following formula is used : 12 C + 36 (H - 0) This is based on the fact that 72 parts by weight of air represent 16 of oxygen. The weight of air theoretically necessary is therefore 12 times that of the carbon -f- 36 times that of the hydrogen, less -| that of any oxygen which may be present in the fuel itself. If the unit employed be one pound, the volume of air at 32° F. may be found by multiplying the weight of air, obtained by the formula, by 12.844, this being the voliune in cubic feet which one pound of air occupies at that temperature. In actual practice, half as much again to twice this amount of air is found to be necessary. In the United States service, the cord of merchantable oak wood is the standard upon which all issues of fuel are based; a scale of equivalents, determined by comparative efficiency in the evaporation of a given weight of water, being published from time to time. At present, the heating equivalents of one cord of oak wood are laid down as follows : Yellow pine 1^ cords. White pine, poplar or cottonwood ll " Spruce or bircli l| " Charcoal 1,706 pounds. Coke 1,707 " % Anthracite coal 1,700 " Bituminous coal from 1,500 to nearly 4,000 " Lignite from 2,500 to 3,000 HEATING AND LIGHTING. 497 A large vaiiety of bitumiiious coals are purchased for issue, and these differ very greatly hi their heating qualities. Usually a coal miaed nearest to a ganison is the one employed. Charcoal was issued to troops in Cuba, but its cost was so great that coal and wood were substituted. Coke is little used. For fixing the allowance of fuel for heating purposes, the United States is divided into several zones. Below the 36th degree of latitude, each non-commissioned officer and private is entitled monthly to one-twelfth of a cord of oak wood or its heating equivalent, dui-iag the period May 1 to August 31; and to one-sixth of a cord from September 1 to April 30. Between the 36th and 43d degrees of latitude the fuel allowance of the soldier is increased by one twenty-fourth of a cord monthly, from Septem- ber 1 to April 30 ; while north of the 43d parallel the allowance is in- creased by one-eighteenth. To provide for the needs of particularly cold posts, it is ordered that in stations situated between the 36th and 43d de- grees of latitude, where the mean temperature during twenty days of any calendar month is not above 20° F., an increase in the allowance of fuel of one-thii'd instead of one-fourth, as given above, is authorized. If the temperature is not above 10° F. for twenty days in any calendar month, an increase of one-half will be allowed, whatever be the latitude of the place. Under all chciunstances, a company is allowed sufficient fuel for the pro- per cooking of its food. Fuel is regarded as public property and not as an allowance, and any imused portion of such as may have been issued to troops is reqmi'ed to be tm-ned back to the quartermaster. Regulations state that the cheapest fuel at the place of issue wiH, all things being considered, be furnished to troops. This may at times work no great harm; but in very cold climates the restriction of a garrison to fuel of an inferior quality, merely because it is slightly cheaper, may be a serious hardship. For troops in the northwest to be required to bm-n the inferior grades of bituminous coal and lignite mined in the vicinity is un- deshable. . Such coal, as that supplied at Fort Assiniboine, gives off comparatively little heat and burns out quickly. It leaves a large amount of refuse ; often in the natm-e of slag which has been melted down by the heat and is not readily removed. The ashes require to be frequently shaken out of the gi-ate, and the ash-pit emptied, with resulting dust. Fm-ther, the fuel contains much sulphm' ; and the fumes of sulphur dioxide which escape into the room, particularly when the stoves are imperfect or hot ashes are being removed, are often highly irritating to the respiratory tract. The smoke produced by coal of this character is very dense, and the chimneys require frequent cleansing of soot to ensure their proper operation. Fires maintained by such fuel require constant attention and imply greater labor of administration ; since much more fuel is required to produce a given residt, and in the combustion of such coal an excessive proportion of ashes remains to be removed. All things considered, it may fairly be questioned whether the use of the lignites and the lower grades of bituminous coal results ultimately in much greater economy than if an- thracite were issued ; this being undoubtedly the fuel most adapted to the needs of the military service. The latter coal is cleanly and easy to handle, and contains a high proportion of heat latent in a given weight. Little smoke or fumes of sulphur are given off, and the resulting ash is 32 498 THEOEY AND PKACTICE OF MILITAEY HYGIENE. comparatively small in quantity. White-ash Lehigh stove-coal gives the best results in stoves and small furnaces; for large furnaces a mixture of stove and small egg-coal is best employed, since the fire can be better regulated and controlled by its use. Wood is still used as fuel at certain stations. Its heating power varies with the amount of moisture which it contains. Green wood may con- tain as much as forty-five per cent, of moisture, and part of the heat pro- duced by combustion is lost in the vaporisation of the latter. Well-dried wood contains but fifteen to twenty per cent, of water; and when wood of this character is used, fires are readily started, the fuel is consumed rapidly and much heat is given off in a short space of time. A practical drawback to the use of wood, therefore, consists in the great difficulty of maintaining an even temperature in rooms heated by its combustion. Wood soon burns out, the supply of fuel has to be frequently renewed, especially with pioe or other soft wood, and squad-rooms heated in this manner are liable to become very cold at night during severe weather. As already intimated, the total heat given out during the combustion of various kinds of fuel varies greatly, and this is a practical point which should be given consideration in connection with heating arrangements. Further, the heat which can be evolved from different specimens of the same class of fuel varies so greatly that a definite knowledge of the heat- ing value of the special kind to be used should be had before any plans for the heating of barracks have been matured. Estimates which have been made of the heating value of various fuels are as follows : P , Fuel value of one '^ '''"• pound, Calories. Charcoal 3,430 Coke 3,467 Anthracite 4,097 Bituminous coal From 1,804 to 4,643 Lignite 2,990 Dry wood 1,830 Petroleum 5,538 The choice of a fuel of course has a close relation to the nature of the heating apparatus available, and vice versa. This would seem so evident as scarcely to require mention; yet at Fort Assiniboine, for instance, after the abandonment of anthracite coal for the local bituminous supply, the stoves intended for the combustion of hard coal were largely left in use and naturally proved of little value for purposes of heating with the new fuel. While the issue of fuel in our service depends upon the number of in- dividuals in an organization, in the British army a more rational method is employed and the fuel allowance is based upon the size of the space to be heated, irrespective of the number of its occupants. At present, in that service, 40 pounds of hard coal are allowed daily for the heating of 7,200 cubic feet. If the space to be heated is of less size than this, a reduction is made ; but since the consumption of fuel in small spaces is proportion- ately greater, the fuel allowance is not reduced quite to the same extent. When troops are in huts, the above allowance of fuel is increased by one- third ; and special issues of fuel may be authorized by commanding officers during cool or damp days in summer. The allowance of fuel in the French HEATING AND LIGHTING. 499 army is based, like our own, primarily upon temperature as depending upon latitude — ^the country being divided for the purpose into five zones. The allowance is made per man and not per cubic space. Usually seven kilograms of wood are allowed daily fox each authorized stove; but supple- mentary issues of fuel are authorized during periods of great cold. As in our own service, no official allowance of fuel is laid down for hospitals in the French or British army, but they are heated according to existing cir- cumstances so as to maintain a constant temperature of about 65° F. The allowance of fuel authorized in our service is often insufficient for the proper heating of barracks at northern stations, though adequate for those further south. Clearly an allowance of fuel which might be suffi- cient for the heating of a weU-bmlt barrack warmed by steam-heat, might be quite insufficient to maintain a proper temperature throughout an old, poorly constructed building, heated by stoves of rapid combustion. Where squad-rooms are smaller and more numerous, and stoves are used, the loss of heat is proportionately greater and the deficiency in fuel rendered even more apparent. To secure the best results with respect to heating, it would seem that each barrack in a post should be considered separately, and the amount of fuel required for its proper warming should be fixed by the commanding officer. In respect to fuel, as in some other matters, a greater elasticity of the regulations governing its issue would be of advan- tage. With regard to officers, present regulations concerning the purchase of fuel by them are not equitable. A limited supply only, graded accord- ing to the rank of the officer, can be purchased at the fixed government rates; any excess being charged for at full contract prices. For very cold stations and for officers of lower rank the official allowances are in practice quite insufficiefit ; and thus junior officers serving in northern stations are doubly placed at a financial disadvantage as compared with those stationed in warmer localities. As a matter of justice an officer serving anywhere, irrespective of rank, should be allowed to purchase at fixed rates such fuel as he might certify was required for his own use, as is at present allowed in the case of mineral oil, commissary stores and clothing. Local Heating. Barracks are warmed either locally or by heat distributed from some central point. By the first method, heat is furnished by the combiistion of fuel in the room itself, either in fire-places or in stoves. The heating is obviously very unequal, and the temperature throughout a barrack building warmed ia this manner usually varies greatly. The system also has very many other defects, which are discussed subsequently. In the French army the local method of heating is the only one employed at most sta- tions, since the allowance of fuel is so small as to be quite insufficient for the heating of an entire barrack buildiag, and hence only certain por- tions of it are warmed. Clearly such motives of economy need not stand in the way of the general heating of barracks in our service, and local heating should be used only under such special conditions as may render it more desirable or practicable. Open Fire-Places. — The use of ordinary open fires and grates is a 500 THEOEY AND PRACTICE OP MILITAEY HYGIENE. most costly and imperfect method of heating, since these practically give out only radiant heat^though it must be understood that objects warmed by radiant heat do, in turn, themselves convey heat to the layers of air with which they come ia contact. It has been shown by Morin and others that with ordinary open fires but six per cent, of the total heat la- tent in wood is secured for the warmiag of an apartment — the rest of the heat being carried up the chimney or escaping as unconsumed carbon. Under f;he same conditions, coke yields to warming purposes but twelve per cent, of its theoretical fuel efficency, and coal about thirteen per cent. The chief sanitary advantages of open fire-places are found in the fact that ordinarily the air of the room heated by their use is not contaminated by the products of combustion, nor is it scorched or dried to any extent. Ventilation is also very free, so much so as at times to present serious disadvantages — since immense quantities of air, far greater in amoimt than is required for the combustion of the fuel, are drawn up the chimney, which acts as a heat-extraction shaft. Notter and Firth state that from 20,000 to 40,000 cubic feet of air, or more, may thus be removed in the course of an hour by an ordinary fire-place — the quantity varying with the difference between the internal and external temperatures, the size and height of the chimney and the size of the fire itself. To replace this loss of air it is evident that an equal quantity must be drawn into the room. If the incoming air were warm, the liberal ventUation thus assured would be ex- cellent ; but unfortunately .this is usually cold, and finds entrance through crevices around the doors and windows or in the floor. This gives rise to numerous knife-like drafts of a particularly chilling character, which increase in intensity with the ■ degree of outside cold and the size of the fire maintained. The entering air is constantly moving toWard the chim- ney shaft, and thus causes cold currents on the backs and legs of persons who may be sitting before the fire, and who may at the same time be un- comfortably warm on the portions of the body directly exposed to the radiated heat. AVhen efforts are made for the diminution of this entering air, down-drafts are almost certain to be created in the chimney; driv- ing smoke and gases into the room and forcing the admission of the neces- sary amount of cold air as the lesser of the two evils. Though this fault may be partially controlled by regulating the chimney current with a dam- per, it is nevertheless clear that with ordinary open fires it is impossible to warm an apartment equally, even imder the best of circumstances. A minor advantage of open fires is the cheerful blaze which they afford ; but with fuel of poor character the fact that the fire is not enclosed renders the possibility of accidental conflagration much greater. In the construction of open fire-places, it is evident that the materials employed should be poor conductors but excellent radiators of heat. The chimney flue should be as small as possible, the fuel surface should be concentrated and set well forward, the side walls of the fire-place should join the back at an angle of 45°, so as to throw as many heat-rays as pos- sible into the room, and for the same reason the top should be inclined forward from the back at an angle of about 55°. There should also be a damper in the chimney, so as to limit the amount of hot an passing up it and consequently the entrance of cold air into the room from outside. To get the best results, Morin recommends that the temperature in the chim- HEATING AND LIGHTING. 501 ney of a fire-place be maintained at least 80° F. above that of the openr air, that smoke should not issue from the chimney at a. rate greater than ten feet per second, and that the outlet of the smoke-flue should have an area one-half that of the flue just above the fire-place. Ordinary open fire-places are obviously not satisfactory for the heating of barracks ; but for winter quarters or where troops are in huts, and no special facilities for heating are provided, as was frequently the case during the Civil War, they may readily be improvised and will prove of much ser- vice under such conditions. To minimise the defects of the ordinary open fire-place, as just de- scribed, certain modifications of structure have been proposed by which a portion of the escaping heat is utilized in warming the entering air. The general principle of these changes, as exemplified in the Galton grate, is shown in Fig. 215. Briefly, the modifications consist in carrying the heat and smoke from the fire through a chimney passing through an air-cham- ber, buHt behind and over the fire-place. This air-chamber opens at its lower part into the external air, and from its higher part into the room by an air-shaft which discharges near the ceiling. The air from outside, on entering this chamber, becomes warmed by passing over the heated back of the fire-place and smoke-flue, and then passes on to enter the room. The movement of the air after entering the room is shown in the illustra- tion just mentioned. It is stated that a ventilating fire-place ,of this gen- eral pattern is capable of utilizing for purposes of warmth about thirty-five per cent, of the available heat in the fuel consumed, or about three times as much as with fire-places of the old model. The Joly fire-place, Jackson grate and Griffith grate are all slight modifications of the Galton grate just referred to. Ventilating fire-places have been used to some extent in our service; chiefly in hospitals, and particularly in the form of the Jackson grate. They work very successfully in climates where the temperature does not go much below the freezing point ; but in zero weather they are imable properly to heat the entering air and the rooms become unbearably cold. The French use them for the heating of barracks at warmer stations, and in the British service their use is the general rule in home garrisons. One Galton grate is the usual allowance, in the British service, to a room containing twelve men or a fraction of that number ; the hot-air duct pro- vided generally having a clear area of one square inch to each 120 cubic feet of room space. When ventilating fire-places are used under the conditions of climate to which they are suited, they give excellent ventilation without drafts, and, as compared with ordinary fire-places, reduce the amount of air as- pirated from a room, from the lowering of the temperature in the chim- ney which is thus brought about. The temperature of the room, from the movements of the entering warm air, is rendered quite equable, and smok- ing of the chimneys is infrequent. If desired, one room over another may be heated from a single fire-place on the lower floor, on the principle seen in the well-known "Baltimore heater." In ventilating fire-places, the chamber for the warming of entering air should be large, and, as shown in the accompanying illustration of the Jackson grate, may be advantageously fluted to increase the heating surface as much as possible. Provision should be made by which this air-chamber can be cleaned out as desired. 502 THEORY AND PEACTICE OF MILITAEY HYGIENE. ^ffff,, Fis. 239.— Jackson's Ventilating Grate, Back View. The outer casing is cut away to show space and surface lor warming the incom- ing air. The exact manner of admitting the air depends on local conditions, as does also the size of the air-shaft. It is important that the entering air should not pass over any iron sm-face which may be raised to a red heat, on ac- comit of the bad odor which results from scorching of the minute par- ticles of dust constantly present in the atmosphere, and from the possibility of the passage of carbon monoxide through the heated metal, or its production from the carbon dioxide of the air through contact with a red-hot surface. The chimney of the fire-place should be furnished with a damper, so that its discharge may be modified in cold weather. Such fire-places work best when the windows and doors of the room are closed ; the volume of warmed air yielded by them varies, to some ex- tent, with the direction of the wind. Since architects in this country are not accustomed to put this mode of heating in their plans, its installment after erection of the builduig implies the demolition of chimneys as already constructed. Stoves. — ^Like open fire-places, stoves may be simple heaters or may be so constructed as to contribute to the ventilation of the spaces they are intended to warm. In stoves of the simplest construction the fire is surrounded directly by the surface to be heated, which, placed unprotected in the room, ra- diates heat and warms the air by direct contact. The air necessary for combustion of the contained fuel is drawn directly from the room, while the smoke is conducted away to the chimney. JSTo special style of stove is regulation in our service, and a large number of patterns are now in use ; the special variety re- quested by the quartermaster of a post being usually approved for is- sue. Where the matter of selec- tion is left to the supply depart- ment, however, the " Pluto " and " Triumph " models are usually fur- nished ; these being powerful heat- ers of a simple pattern very suitable for use in squad-rooms. These stoves can be adapted to either hard or soft coal and possess many points of merit. Their greatest disadvan- tage consists in the absence of any provision by which the necessary moisture can be imparted to the fw. m-The"piuto" Barrack stove. HEATING AND LIGHTING. 503 heated air. This is a point which might easily be remedied by some simple improvised arrangement, but ia practice it rarely is. Smaller stoves are generally issued for officers and quarters. When anthracite coal is used, these smaller stoves are generally self-feeders ; the fire being automa- tically fed from a coal magazine above, iustead from the side by a fire-door, and thus reducing the amount of attention required. Wood stoves are still used at some western stations — as at Fort Yellowstone — where fuel of this sort is abundant and coal can scarcely be supplied on account of the great cost of its transportation. A number of varieties of wood stoves, like those for coal, are supplied for issue. The official allowance of stoves for a company is two large stoves for the squad-room, one large stove in each mess and day room, and one small stove for each of the two rooms for non-commissioned officers. For each six civilian employees, or for each room occupied by them as quarters, one heating-stove is allowed. With the old company strength of sisty men, it was entirely a question of climate and barrack construction as to whether the above allowance was sufficient. Under some circumstances the authorized allowance of stoves was certainly in- adequate, but in practice there was usually no diffi- culty in obtaining the number required. With the enlargement in the company strength to about double its former number, the official allowance should be proportionately increased. When stoves are used in officers' quarters there is rarely any trouble in obtaining the number desired; though this, in cold climates, is almost invariably much in excess of the official allowance. Stoves are economical in fuel in proportion to the heat evolved for warming, and the quantity of heat which passes up the chimney is rela- tively small. Ordinarily, stoves of rapid combus- tion utiUze about 60 to 65 per cent, of the heat available in the fuel, and those of slow combustion utilize from 80 to 90 per cent. "\\Tien the draft is too free, considerable wastage of fuel results; Gautier having shown that the heat available for warming, with different kinds of fuel, is nearly twice as great when only the amoimt of air actually required for combustion is admitted to the stove as when an amount of air twice as large as is necessary is allowed to pass tlu:ough the fire. Where the stove- pipe is carried some distance across a squad-room, much of the heat which would otherwise escape with the products of combustion is dissipated before arrival at the chimney and is thus economized. To get the maximum effect of heating, a stove should have as much exposed surface as is possible without diminishing its heating capacity. The relative heating surface needed for any given space warmed by a stove may be approximately de- termined from data given by Peclet, who found that one square foot of sheet iron, under ordinary conditions, freely exposed to the air, will yield about 200 heat units per hour; a square foot of cast-iron, 500; and bricks or tiles, two-fifths of an inch thick, 180 heat units — supposing the fuel to Fig. 241. —The "Triumpti' Barrack Stove. 504 THEORY AND PEACTICE OF MILITARY HYGIENE. be consumed in such a manner as to yield about 80 per cent, of its theoret- ical heating power. The materials of which stoves are made are cast-iron, sheet-iron, brick or tiles. When fuel is rapidly burned in a stove, so as to evolve in a short space of time the entire amount of heat it is capable of affording, the tem- perature produced is often greater than required. Iron, and especially cast- iron, which conducts and radiates heat rapidly, is therefore not an appro- priate material for maintaining a \mif orm temperature — since fires in such stoves require constant attention to maintain regularity of operation. Clay, in the form of brick or tile, is far preferable; since it parts with its heat slowly and gradually, and the surrounding air is maintained at a more even temperature. Hence the best results are obtained by a combination of materials, as an iron fire-box with a lining of fire-brick, by which the stove is enabled to heat up fairly rapidly, yet not give up its heat too fast. This arrangement also prolongs the life of the stove, since when constantly over- heated it rapidly deteriorates in character. With ordinary stoves the amount of direct contamination of the air, which is usually not inconsiderable, depends upon the tightness of their joints, the proper employment of dampers and the avoidance of over-heat- ing. The last, as just explained, may generally be secured by a lining of fire-brick. The production of carbon monoxide and the odors resulting from the scorching of minute atmospheric particles, the vast number of which can be appreciated by watching the path of a sunbeam in a darkened room, are thus avoided. Broken or badly constructed stoves are highly unsanitary and may give off dangerous gases, as carbon monoxide. Badly jointed stove pipes may give out much impurity to air, while the separation of sections of pipe is liable also to result in accidental fires. Base-burner stoves are, by careless soldiers, often damped off to reduce the heat, by closing the valve between the stove and the chimney instead of those which admit air to the fire. In this way the products of combustion are forced into the squad-room under pressure, producing headache, dizziness, languor, loss of appetite, nausea and other symptoms. In some instances, the poisonous gases from improperly damped stoves have been inhaled in. sufficient quantity to produce death. 'Putzeys states that, during the pe- riod of 1867-70, there were 170 cases of asphyxiation in the Prussian army from the fumes of burning coal, and that 45 of these terminated in death — as a result of which the use of such dampers was forbidden in that service. While the dampers used in our stoves probably do not fit suffi- ciently tightly to justify any apprehension of fatal poisoning, their misuse undoubtedly does much to cause contamination of the air and produce toxic symptoms of no little iatensity. The manipulation of the stoves in a squad- room should, therefore, be prohibited to all but the room-orderly or the non-commissioned officer in charge of a squad. Stoves have the practical dis- advantage of occupying space in the squad-room. They requii-e much atten- tion, particularly in very cold weather and with inferior fuel, and their ma- nipulation is productive of dust, noise and confusion. The fine impalpable powder produced in shaking down the ashes, or in their removal, is irritat- ing to the respiratory tract and interferes with the maintenance of proper cleanliness in the squad-room. Equability of heating for any considerable period is not to be secured with stoves, and usually the fires are allowed to HEATING AND LIGHTING. 605 ■die down to a considerable extent during the night. Stoves, however, fur- nish an economical method of heating under circumstances and conditions where central heating is not practicable or is not required. They distribute heat more equably throughout an enclosed space if located at or under the center of the latter ; through their chimneys they act as extracting shafts — an additional reason why they should be given a central position. No stove is complete without an evaporating vessel, kept full of water to supply the necessary amount of moisture to the heated air. Ordinary stoves do not contribute to ventilation, except in so far as a comparatively small quantity of air is passed through the fire in the support of combustion. This lim- ited amount of air is drawn from a point close to the floor, and thus there is little movement of air in the upper levels. Since the air required for combustion is taken directly from the room, incoming air-currents are nec- essarily established. — -but the drafts are by no means as severe as with open fires. For squad-rooms, it is well to guard its vicinity from an excess of heat by surrounding the stove with a sheet-iron cylinder, extending from the floor to the top of the stove. Presh air may be admitted under the stove, and is thus heated as it is passed over its sm-face upward into the room. If, in addition, the stove-pipe be so placed as to warm a flue for the escape of foul air, and an opening be made in the latter near the floor, an excellent arrangement for warming and ventilating the squad-room, equably and without the production of drafts, is thus secured. This plan is illustrated in Fig. 217. No stoves of ordinary construction should be put into a squad-room without being arranged in some such manner. With the purpose of improving upon the arrangement for combined heating and ventilating, just described, a number of varieties of ventilating stoves, depending on the same general principle, have been devised. These merely consist of an inner fire-box surrounded by an outside metal envelope, which provides for the circulation and warming of air in the in- termediate space and reduces the intensity of radiation. It is evident that for true ventilation the air warmed in this intermediate space must be drawn directly in from the outer air. Some so-called ventilating stoves merely heat air already in the room and have no connection with that out- side ; thus clearly ihaving no value as ventilating agents and possessing no special merit save that of establishing circulating air-currents by which the more equable warming of an apartment is probably secured. Ventilating stoves are much used in the German army, and have been employed to a considerable extent in our own service. The pattern gener- ally issued is that of the Cortland Howe ventilating stove, which is re- garded as the best variety by the Quartermaster's Department. This stove operates very satisfactorily as far as the diffusion of heat is concerned; thermometric tests showing a difference in temperature of only three to five degrees at points just above the floor and below the ceiling, in rooms containing about the cubic space which this stove is guaranteed to heat. With respect to ventilation, the results are not so satisfactory. Tests show that this stove is capable of warming and introducing only about 1,600 cubic feet of air per hour; a quantity which might be considerably increased by a breeze blowing into the cold-air pipe, or which might be somewhat reduced by air-currents from the opposite direction. With two such stoves in a squad-room containing twenty-four men, it is obvious that 506 THEOEY AND PRACTICE OE MILITARY HYGIENE. the quantity of warmed fresh air introduced would scarcely suffice for the needs of a single individual. As seen by the accompanying illustration, the Cortland Howe stove is provided with a heat-aspiration shaft, opening near the floor. This shaft appears to be able to remove a bulk of foul air equal to that of about four-fifths of the entering fresh air ; the remaining quantity being utilized in the combustion of the fuel or passing through the fire to escape by the chimney. This heating apparatus is excellent in theory, and works well m practice so far as its operation goes ; but its air-passages are too small and as a ventilating agent it is much over-rated. Further, it has no provision by which tlie entering air can be suppKed with its proper amoimt of moisture. In determining the size of the intake with ventilating stoves, together with the number of the latter required, Putzeys states that this may be estimated, for a space having a known cubic contents and number of inmates, from the fact that one kilogram of coal burned is capable of raising the temperature of 900 cubic meters of air, moving at the rate of two meters per sec- ond, to the extent of 20° C. From the constant supply of warmed fresh air which is drawn in from the outside, the cold drafts caused by stoves of the ordinary pattern are avoided with this model. The apparatus is stated to be gas-tight, and to be incapable of being heated to a red heat. It does not require the combustion of any excessive amount of fuel. This stove, like many other ventilating stoves, is claimed to be a better heater than those of ordinary pattern. This is not the case, for Morin has shown that the latter may be capable of utilizing ninety per cent, of the theoretical heat of combustion. Further, the introduction of volumes of newly heated air, by ventilating stoves, is inseparably con- nected with the expulsion of an equal volume of foul air, which carries with it a certain amount of heat. Hence it foUows that tlie ordinary stove may actually be more economical as regards heating than the ventilating pat- tern, though the better distribution of heat by the latter may give the im- pression of greater warmth. Chimneys. — It frequently happens that a chimney will smoke vigor- ously when a fire is first started, especially when it has long been disused. This is generally due to a low temperature of the air in the chimney, and an inability to cause its displacement upward. Such a condition is ob- viously only temporary and disappears as soon as ascending currents of Fig. 242. -Cortland Howe Ventilating Stove. HEATING AND LIGHTING. 507 hot air are established. If the smoking is continued, it may be that the chimney is clogged with soot ; that bricks have been blown in from the chimney-top and thus obstructed the shaft; that descending air-currents have been created by neighboring buildings; or finally, that several chim- neys running from the same space, or several connecting spaces, are work- ing against each other. If the chimney is stopped with soot and needs cleaning, the fact may be told by inspection ; while a stoppage by bricks is readily detected by sounding from the roof with a line and plummet. The actual location of such a stoppage, if one exists, may be found by an assistant, who listens at the chimney, from several floors, while the plum- met is being struck against the obstruction. The latter may be readily lo- cated for removal, generally only to be accomplished by tearing a hole in the masonry of the chimney, by the noise produced by the impact. Descend- ing air-currents may be caused by the deflection of wind from neighboring buildings, and may occur even when the latter are at some little distance. They may generally be caused to disappear by building up the chimney sev- eral feet higher and protecting its outlet with a suitable upcast ventilating cowl. Where several chimneys work against each other, as in several ad- joining rooms having free air communication, the smoking may be caused to cease by destroying this air communication by closing the doors between them. If several flues, from the same room and of equal height, work against each other, either all should be brought together into a single shaft with a suitable cowl, or all but one should be closed. In this connection, it may be^ mentioned that stove-pipes and chimneys should be kept free from soot, not only for the better draft which is thus afforded but to limit the liability of the soot catching fire. The frequency of cleaning obviously depends upon the character of the fuel used and the amount burned. With bituminous coal the proportion of soot produced is relatively large. Chimneys are best cleansed, after stopping up all holes for the entrance of stove-pipes with wads of newspaper or gunny-sacks, by going on the roof and letting a loop of chain on the end of a rope dangle down the chimney, moving it up and down so as to scrape it over the sides of the flue and thus dislodge the soot. The latter is then removed from the bottom of the shaft. Stove-pipes are best cleaned by taking the sec- tions carefully apart and removing them to the open air for scraping and brushing. When the soot in a stove-pipe or chimney takes fire, the com- bustion may be stopped by throwing a handful of sulphur into the stove ; the fumes of sulphur dioxide thus produced promptly smothering the flames in the chimney shaft. m Central Heating. In central heating, air heated in furnaces is distributed through the various spaces to be warmed ; or the heat resulting from the combustion of fuel is stored in water or steam under circulation, to be dissipated where required by contact and radiation. Heating by electricity being about fif- teen times as expensive as by the use of the methods just mentioned, it obviously need not be considered in connection with the military service. In general, the use of steam gives better results in very cold climates, while 508 THEOEY AND PRACTICE OF MILITARY HYGIENE. the hot-water systems are more applicable to localities in which the tem- perature is never excessively low. Under all circumstances, heating by hot-air furnaces may be regarded as less desirable than the methods just mentioned for securing warmth in barracks. The advantages of central heating plants include an economy in fuel and labor, cleanliness and freedom from dust, the equable distribution of heat throughout an entire building and the possibility of maiutaiaing a more uniform temperature for long periods. The last can be readily secured by the use of automatic thermostats when great variation of the outside temperature does not occur ; but, on the whole, the efficiency of a central heating system is dependent to a considerable extent upon intelli- gent operation. The warming of fresh air required for ventilation is also more satisfactorily performed with central heating plants, and the pro- duction of cold drafts is reduced to a minimum. In our service, central heating is employed only ia barracks of fairly recent construction or those which have been lately remodeled. Since many slightly different meth- ods of central heating have been applied to barracks in our own and for- eign armies, it is impossible here to point out the special defects or advan- tages of this or that system ; and merely general types of the chief systems in common use can be considered. Heating by Hot Air. — When want of space or other considerations render it desii-able to have fires located away from the rooms to be heated, the necessary quantity of air can be warmed in another part of the build- ing and conducted by flues to the desired points. This air is generally heated by the use of the hot-air furnace — a device which is practically nothing but an enlarged pattern of the ventilatiag stove, being, in its es- sentials, an air-tight fire-box partially enclosed in an outer envelope ; air from outside being drawn into the intermediate space, warmed, passed over a water reservoir and then distributed as required. With respect to the more minor details, hot-air furnaces are constructed according to either of two systems. In one, the smoke and hot gases from the fire are caused to circulate in an extensive system of stone-ware or metallic flues, and the air to be warmed is conducted from the outside of the building to around these flues. In the second system, the conditions are reversed and the air itself is conducted through similar pipes, arormd which the flame is allowed to play. Although there are a large number of hot-air furnaces on the market, they all, however they may differ in appearance or detail, conform in principle to one of these systems. No special pattern of hot-air furnace is used in our service. The hot-air fiunace being, as just stated, practically a large ventilating stove, it is beset with many of the disadvantages attending that apparatus. It has, however, many positive advantages. The system secures the con- stant admission of fresh warmed air, and hence ventilation is excellent if an outlet be provided ; for volumes of air are thus forced in from outside, in place of the exhaust resulting from combustion in a stove in the room itself. The result is that instead of there being cold air-currents entering through existing cracks and crevices, the constant tendency of the air is to move outward and there are no drafts. The equable heating of buildings is also generally secured with hot-aii' furnaces ; but the distribution of warmth may not be good in high winds, and the rooms on the exposed side of bar- HEATING AND LIGHTING. 509 racks are liable to be cold and cheerless under such conditions. Some- times fans are used to overcome this defect and secure the equable distribu- tion of the heated air. If the distributing pipes are much bent, the loss of head by friction may be so great as to prevent the proper warming of a room except under very favorable conditions. The flues also accumulate dust, which further operates to retard the passage of air through them. Gen- erally, the warming influence of hot-air furnaces is limited to a radius of thirty-five to forty-five feet; and in a large building the idea of concentra- tion is niusory, if a number of furnaces are required. This method of heating is also not desirable where the number of rooms to be warmed varies, since furnaces of this character are not adapted to meet a fluctu- ating demand. The entering air also is often scorched by passing over too hot sur- faces, and thus may present a bad odor. With such over- heating, moreover, the air enters the room at too high a temperature, and there is no way of properly diluting it with fresh cold air. Under these condi- tions, recourse is usually had to par- tially or wholly closing the valves of the register, but this destroys venti- lation by cutting off the supply of fresh air. Careful atten- tion to details will do much to minimise the faults of the hot-air system. Where strong cold winds prevail from one direction, the furnace should be located near the windward side of the building ; for it is said to be as difficult to move the heated air ten feet against a fairly strong wind as forty or fifty feet with it. The furnace and air-shafts should be kept scrupulously clean ; the registers in squad-rooms, particularly if in the floor, are liable to accumulate dust and refuse and should be removed at frequent intervals to permit of po- licing. Great care should be had that all joints are tight in the furnace proper and that the air-heater is entirely disconnected; since otherwise the gases are carried over the entire building. The heat applied to the entering air should not be of too high a degree, but should be sufficiently protracted to give the required temperature. When a furnace wiU not Fig. 243.— Common Pattern o( Hot-air Furnace. 510 THEORY AJSTD PRACTICE OF MILITARY HYGIENE. warm a building during cold weather without itself becoming over-heated, it is either too small or has too little heating surface in proportion to the fire-pot. Care must be had that the evaporating pans constantly contain water. The air-supply should not be taken from the cellar, even though the latter be apparently clean and free from any contamination with soil- air, but should come from a clean source out of doors, well above the ground level and from the direction of the prevailing winds. The cold-air duct or ducts should be screened at the entrance to prevent the admission of refuse or vermin, should be arranged to permit of regular cleaning, and should have a cross-section equal to eighty per cent, of the combined area of the hot-air flues leading from the furnace. The shaft for cold air should have a damper to regulate the admission of the latter. The use of this damper should be intelligently administered by the soldier in charge and should be frequently inspected ; for it not rarely happens that the fact of the damper being wholly or partially closed is overlooked for consider- able periods, during which the supply of air is drawn in from the cellar and is often highly impure. It may be desirable to provide for the filtra- tion of the entering air through coarse cloth or fine wire gauze, especially if there be much dust in the incoming air. If possible, the hot-air flues or ducts should not be flat, but round or square, to lessen the friction; and for the same reason they should be as direct in their course and as nearly vertical as possible. They should be covered from the furnace to the register openings with asbestos or other non-conducting material, to prevent the loss of heat from them that otherwise occurs into the cellar and between partitions. Their register openings into the rooms should not face the windows or prevailing winds unless absolutely unavoidable ; for if they do, the passage of warm air into the room will often be com- pletely checked. It has been proposed so to construct flue openings as to break the entering hot air into numerous cxnrents, which are directed downward at a steep angle with the floor. The air is thus caused to enter in exactly the opposite way from which it would naturally take, and in its effort to change its direction the heated fresh air is thus more completely mingled with the air of the room and without producing un- pleasant drafts. From what has been said, it is apparent that the hot-air system possesses many defects as regards the heating of barracks, as compared with steam or hot water. It is, however, a decided improvement over heating by stoves. The hot-air system, in our service, has of late been in- stalled only in long-estabUshed posts and generally in old buildings. None of the barracks constructed during the past eight years have been heated by this method, but it is still employed in a considerable num- ber of the older posts. At Madison Barracks, a system providing for the propulsion of the heated air by fans has been installed, but generally reliance has been had upon the natural upward movement of the heated air itself. In installing the hot-air system of heating, or in remodeUing existing arrangements which are unsatisfactory, the size of the heater and of the air shafts required should be known in advance. Calculations as to the size of registers and hot-air pipes to be used are frequently imsatisfactory, and reliance is usually had, in this country, upon dimensions which have HEATING AND LIGHTING. 511 been found by experience to be sufficient under certain conditions of climate. For the climate of Chicago and the northern part of this country, the subjoined table is generally followed; it being assumed that aU hot- air flues are placed in interior walls. Cubic feet of air that can be kept properly beated In rooms having one side exposed. 1,600 1,800 3,300 2,300 2,700 3,500 4,500 5, .500 6,500 8,000 11,000 14,500 30,000 25,000 30,000 40,000 Total size of register to be used. 8X10 9X13 10X13 10X14 13X14 12X15 12 X 19 14 X 22 16X30 20 X 30 20X26 24x37 27X27 30X30 27X38 30X42 Hot-air capacity of register used, in square inches. 53 72 80 93 102 120 153 205 214 267 347 433 486 600 684 840 HOT-AiR Pipe to be used. Size, inches. 10 10 12 12 13 14 16 18 30 23 34 28 39 31 Capacity in square Inches. 50 64 78 78 113 113 133 154 301 254 314 380 453 616 661 755 For the climatic conditions found in New York city and points south of the same, the following table is usually employed : Cubic feet of air Total size of register to be used. Hot-air capacity of register, in square inches. Size of Hot-air Pipe to be used AND Capacity of Same. beated In rooms having one side exposed. Size In inches. Capacity in square Inches. 1 800 8X10 8X12 9X14 10X14 12 X 15 12X9 14x32 16X24 20X20 30X34 31 X29 24x24 27X27 30X30 30X36 40 58 73 93 120 153 305 356 267 320 406 384 486 600 720 8 8 9 10 13 13 14 16 18 20 31 32 34 38 30 50 1,800 50 3,350 63 3,800 78 4,400 113 6 100 136 8,000 154 10,800 201 14 700 354 33,000 314 £6 000 352 31,000 380 34 000 452 44,000 616 50,000 707 With regard to the heating power of furnaces, the following table is based upon the climatic conditions found iu New York city and points to the south. For colder localities the number of rooms which can be heated, as given below, must be decreased. Usually an allowance of fifteen to twenty per cent, is made in this respect. 512 THEOEY AJSTD PEACTICE OF MILITARY HYGIENE. Furnaces. Heating capacity. Estimated size of air, boxes from west, northwest, or north. 6 rooms 14 x 14 each. 7- " " " " " 8 .. . u . . 9 " " " " " 10 " " " " " 12 " " " " " 14 " " " " " 16 " " " " " 12 X 24 inches. 40 " " 12 X 28 " 44 " " 12 X 33 " 47 " " 13 X 35 " 50 " " 14 X 34 " 55 " " 14 X 40 " 60 " " 14 X 47 " 66 " " 14 X 54 " Heating by Hot Water. — By reason of the high specific heat of wa- ter, the latter serves excellently for the storage and transportation of heat and its distribution where required. The quantities of heat contained in equal weights of water and air at the same temperature are in the ratio of 421 to 100; or the heat which is set free when water cools down one hun- dred degrees is sufficient to raise the temperature of 4.21 times its weight of air to the same amoimt. But for the same weight, air occupies 775 times the space that water does, and hence one cubic foot of water, losing one de- gree of heat, is theoretically capable of raising the temperature of 3,250 cubic feet of air by one degree ; but in practice a small deduction is usually made for warming the moisture present in the air, and it is generally as- sumed that a given volume of water, in cooling a definite number of degrees, will raise the temperature of 3,000 times its own bulk of air to the same extent. It is evident, therefore, that a small quantity of heated water is capable of warming a relatively enormous volume of air. Heating by hot water is conducted by either the low-pressure or high- pressure system. With water at low pressure, the distributing pipes are so arranged as to form a loop through which the water circulates. Usually the piping employed is about four inches in diameter. The boiler in con- nection with this piping is commonly placed in the basement of the build- ing, and from its upper part rims a main pipe, dividing into lateral branches which may extend to the furthermost parts of the building. These lateral branches, at their terminations, are expanded into radiators so as to promote the dissipation of the conveyed heat. A return pipe runs from the bottom of each radiator, and passes back, underneath the distributing pipe, to discharge its cooled water into the boiler at its lowest part. The circu- lation is open to the air at its highest point, where the main distributing pipe opens into a tank which provides for any expansion and permits the escape of air ; while a valve at the lower part of the system automatically admits cold water to replace any losses as they occur. The operation of the system depends upon the fact that water on being heated becomes of lesser density than when cold, and thus tends to seek a higher level. Having given up its heat to the various rooms and become heavier, it is passed on to return to the boiler, which is the lowest part of the system, to be re- heated. A continuous circulation is thus ensured, the motive power being gravity. The circulation being open to the air at one point, the high- est temperature possible at or near the top, where this opening is, does not exceed 212° F. At the deeper portions it may be higher; but the average temperature in the distributing circulation rarely exceeds this point. For HEATING AND LIGHTING. 513 both the distributing and return pipes the average temperature is generally estimated at about 140° F. The calculation of the flow of water in the circulation is very similar to that of air, the head being due to difference in the densities of hot and cold water. To find the head for any circulation, the latter may be con- veniently divided into foot-sections by horizontal parallel planes one foot apart. By measuring the temperature in the flow and return pipes of each sectiofi, the head of the whole circulation wiU be the sum of the differences of temperature of corresponding sec- tions, multiplied by the coefficient of expansion of water. The average tem- perature in the flow and return pipes will be between 92° and 212° F. and for this range the mean coefficient of expansion of water is given as 0.000318; hence the head for each foot-section = 0.000318 (t— t'). However small the head may be, there win be a flow of some sort, provided there is a continuous channel filled with water from the boiler and back again. The precise velocity depends not only on the head but also the re- sistance. Its computation is subject to the same laws as those governing re- sistance in air channels; but, as such calculation is very intricate, most engi- neers work empirically from known successful arrangements. The system of heating by hot water under low pressure operates with great regularity. Since water possesses a high specific heat it does not cool down rapidly, and where equable and continuous heat is required this method of warming possesses many, advan- tages. By this system, the heating begins when the fire is lighted and gradually increases in degree, continuing for hours after the fire is out and imtil the water is cold. The heat in any of the radiators can be con- trolled by opening or closing its valve, without affecting the operation of the remainder of the system. The temperature of the various rooms can thus be regulated as desired ; while the heating, as a whole, is controlled by the intensity of the fire, enabling much or little heat to be obtained as re- quired by variation in the external temperature. Other advantages of the low-pressure system are found in the fact that the temperature of air com- ing in contact with the heaters cannot be unduly elevated and thus scorch- ing of the atmospheric particles is avoided. Ventilation is readily secured with this system, which obviously can in itself in no way impair the quality of the air. The apparatus required is simple, is noiseless in operation, easy of manipulation and can be run at comparatively low cost. Since it is provided with an open expansion tank, the production of steam is avoided and the system is free from the danger of explosion. During periods of 33 Fis. 244.— Diagram of Low-Pressure Hot- Water System. 514 THEORY AND PEACTICE OF MILITARY HYGIENE. disuse during cold weather, however, it is important that the water con- tained in the apparatus be drawn oif , to avoid the possibility of freezing and the resulting broken pipes. An objection to the use of this system ia places which are intermittently heated, as drill halls or gymnasia, is found in the time required properly to heat the considerable bulk of water employed. A question of very practical importance is how much hot-water piping, of a given external diameter, is necessary for the heating of a given room. The answer to this depends upon a large number of conditions, more espe- cially as to the loss of heat through the walls and windows as well as that carried out by the air ia process of ventilation. Much of present informa- tion on this matter is due to Hood, who says that an iron pipe four inches in external diameter loses 0.851 of a degree of heat Fahrenheit when the excess of its temperature is 125° F. above that of the surrounding air. He estimates also that one foot of a four-inch pipe wiU. heat 222 cubic feet of air 1° F. per minute, when the difference between the temperatures of the air and the pipe is 125° F. The following table, from Hood, shows the length of four-inch pipe at 200° F. necessary to warm 1,000 cubic feet of air at varying iuternal and external temperatures. If the diameter of the pipe is increased in any ratio, the length required will be reduced ia the same ratio. Thus 100 feet of four-inch pipe can be replaced by four- thirds of 100 feet, or 133 feet, of three-inch pipe, and so on. Temperature Temperature, in Degrees Fahrenheit, at which the Room is Required TO BE eept. 50°. 55°. 60°. 65°. 70°. 75°. 10° F 150 ' 143 185 127 130 112 105 97 90 82 75 67 60 52 45 87 80 22 15 7 174 166 159 151 143 135 128 120 113 104 97 89 81 73 66 58 50 43 34 37 19 200 192 184 176 168 160 152 144 136 138 120 112 104 96 88 80 73 64 56 48 40 229 330 313 204 195 187 • 179 170 163 154 145 137 129 120 112 104 95 87 79 70 62 259 251 242 233 225 216 207 199 190 181 173 164 155 147 188 139 131 113 103 95 86 293 13 283 14 374 16 365 18 356 20 33 347 238 24 239 26 330 28 311 30 203 33 198 34 184 36 175 38 166 40 157 42 148 44 139 46 130 48 131 50 112 To obtain the amount of radiating surface required for a given room and to compensate for heat lost from walls, wiadows and doors, Baldwin gives the following rule : Take the difference ia temperature in degrees Fahren- heit between the lowest outside temperature to be provided for and the temperature at which the room is to be kept, and divide it by the differ- ence in degrees Fahrenheit between the temperature of the pipes and the temperature at which the room is to be kept. Multiply the quotient thus HEATING AND LIGHTING. 515 obtained by the number of square feet of glass plus the number of square yards of external wall surface in the room, and the product will be the number of square feet of radiating surface required. This calculation does not provide for any leakage of air through crevices or for any change of air by ventilation. To allow for this, the additional calculation is made of multiplying the number of cubic feet of air admitted per hour by the num- ber of degrees Fahrenheit which they are to be heated, the product being divided by 12,500. The quotient is the number of square feet of radiating surface required to allow for ventilation ; and this should be added to the number of square feet of radiating surface, as calculated above, for a room without such ventilation. In practice, empirical rules as to the size of the radiators, varying with the locality, are generally followed and give excellent results. A very satisfactory rule much used for determining the number of square feet of radiating surface necessary to warm a given space consists in multiplying together its three dimensions of length, breadth and height, expressed in feet, and dividing the product by a divisor varying from 25 to 30, according to the locality. The result gives the amount of radiating surface required. Usually the number 25 is employed as the divisor where cold climates or exposed rooms are concerned. By many, also, the last named number is used under all circumstances ; they preferring to regulate the heat by manipulation of the fire, and to thus have a sufficient radiating surface to meet the emergencies of very cold weather without the necessity of maintaining an unduly hot fire in the heater. Eadiators, whether for hot water or steam, may be of many forms, ver- tical or horizontal, and composed merely of a series of large condensing pipes or of the more elaborate special arrangements commonly employed. They are best placed immediately under the windows of the squad-room and covering the openings for the admission of outside air. The cold air thus admitted passes up between the pipes of the radiator and is warmed before escaping into the room. The details of this method are shown in Fig. 216. Another advantage of locating the radiators below the windows is seen in the fact that descending currents of air, chOled by contact with the windows, are thus warmed and their unpleasant action is neutralized. Sometimes radiators are located in the middle of the squad-room. This is a bad arrangement, since the room is much less equably heated, con- siderable space is lost for administrative purposes and the entering air passing in through registers beneath them must traverse long shafts — necessarily containing at least one right angle and certain from the nature of things to become and remain foul from the deposition of dust. When placed against the wall, however, the radiator is less readily got at from all sides and careful inspection will often reveal behind them unsanitary accumulations, the existence of which had not been suspected. This is particularly a fault of the direct-indirect apparatus as used in our service, since this radiator is built up solidly from the floor, and is especially hard to keep clean. The air-box of the radiator requires to be inspected at least once a month, and the top gratings should be frequently removed for p\ir- poses of cleanliness. There are a large number of patterns of low-pressure water-boilers, but the best are those in which the water is caused to circulate in small pipes so distributed as to make the most of all available heat. The accompany- 516 THEOEY AND PRACTICE OF MILITARY HYGIENE. Fig. 245.— Side View of Boiler, Showing Cir- culation ol Water and Amount of Water Surface Exposed to the Heat. ing cut of the " Perfect '' boiler shows the great amount of heating surface exposed to the direct action of the fire. In this apparatus, the water, in the process of heating, circulates twice around the fire-pot, then enters the first water section, passing across this section into and across the next water section, and so on, crossing and recross- ing the rising column of heat ; the bot- tom of the V-shaped channels being nearest the fire, the small body of water circulating therein absorbs heat and ex- pands and rises up where the channels are larger, thus maintaining a positive circulation with the minimum of friction. In this heater, every particle of water is. compelled to travel around and over the fire seven times before reaching the mains, thus absorbing the greatest pos- sible amount of heat from the flame and gases in their course from the fire-box to the smoke-flue. Owing to their pe- culiar construction and the small body of water contained in each section, a po- sitive and rapid circulation is caused through every part of the heater which prevents the accumulation of sediment and makes it a very powerful circulator. The fire-box of this heater holds sufficient fuel to last from eight to twelve hours, thus requiring but little attention. The low-pressure system of hot-water heating is used to a considerable extent in our service. It is much used for the warming of officers' quarters and is commonly put into barracks at all but the coldest stations. For hos- pitals, it is the method of heating generally employed. The system is regarded by the Quartermaster's Department as being much safer and less liable to accident than is the high-pressure system, and hence, where hot- water heating is to be used, it is the method which is commonly selected. A combination hot-air furnace and hot-water system has been em- ployed to some extent in civil life. In such a system the water -heating surface is obtained by inserting a coil of pipe in a hot-air furnace, and certain rooms are thus warmed by the hot ah while others are warmed by hot water. This system is theoretically excellent for certain conditions, but practically it is difficult to design and construct in such a manner that the supply of heat to different rooms shall be positive and well distributed. The arrangement has no special applicability to the military service. In the high-pressure system the water is completely enclosed in WTOught-iron pipes, whose internal diameter is usually -^ inch and external diameter 1^ inches and which are sufficiently strong to with- stand the pressure corresponding to very high temperatures. Thus the pressure required to prevent steam from forming at 212° F. is 14f pounds per square inch; at 300° F. it is 67 pounds and at 400° F. it is 250 pounds per square inch. The small iron pipes are so arranged as to HEATING AND LIGHTING. 517 form a complete circuit, as in the low-pressure system; part of it being coiled within and exposed to the heat of a fire. At the top of the circuit there are one or more larger pipes called expansion tubes. These contain half air and half water, and therefore allow for the expansion of the latter without explosion. When the pipes have been filled with water they are closed with screw plugs ; making the whole circuit practically a closed ves- sel full of water except at the top, where there is an air space amounting to 15 to 20 per cent, of the total capacity of the pipes. The temperature is regulated by the amount of pipe within the fire as compared with that without it — the proportion varying from 1 : 16 to 1:10 according to circum- stances. The temperature also depends upon the height of the fire itself. Once started, the circulation of hot water within these high-pressure pipes is very rapid. The water is heated much above the normal boiling-point and the system is usually operated at a temperature of 300° F., though sometimes greater pressures are employed. With the high-pressure system, the quantity of water contained in the circulation pipes is very much smaller than with the low-pressure system, and hence it can be raised to a heating temperature in a much shorter time. This period of preliminary heating is said to be only one-sixth of the time required for the production of steam. On the other hand, there is no such reserve of heat as with the low-pressure system and the water cools down rapidly as soon as the fire is extinguished. The system is easily in- stalled, easy of operation and economical of fuel. One of its faults consists in the irregularity of temperature found in differ- ent parts of the same loop of piping, and there is some difficulty in regulating it ac- cording to the needs of the moment. High- pressure pipes are also liable to over-heat the air and may be a cause of accidental fires. Putzeys states that wood is carbon- 'i^ed at a temperature of 2&7*'r., and is capable of combustion at 343° F. Hence it is desirable that these pipes should be isolated from aU inflammable substances. As with stoves and furnaces, the odor of scorching from contact of atmospheric par- ticles with an over-heated surface is present with this system. This occurs where the heated surface has a temperature of 285° F. or above. The high-pressure system has, in the past, led to some very disastrous explosions ; at present the pipes are usually tested for one hundred atmospheres, although in prac- tice the pressure rarely exceeds six atmospheres. Since, in addition, there are often automatic valves connected with the expansion tubes, it would seem that this apparatus should be quite safe and explosions no longer li- able to occur. As with the low-pressure system, if the water is left in the Fig. 846.— Diagram of High-Pressure Hot- Water System. 518 THEOEY AND PRACTICE OF MILITARY HYGIENE. pipes in unheated buildings, during cold weather, it is liable to freeze. This may be avoided, if necessary, by the use of a solution of calcium chloride in the pipes. In spite of the fact that the water is iu a closed system, a certain amount of wastage occurs which necessitates the periodi- cal addition of a fresh supply. Where the high-pressure system is employed, the necessary area of radiating surface is much reduced when compared with the low-pressme system, through the higher temperature which is reached in the former. The length of the pipe required for radiation can usually be found from 2 252 d rt' t) the formula ^^^ — ^ = L, in which d is the number of cubic feet D (T — t ) of air to be warmed per minute, t' is the temperature to be maintained in the room, t is the lowest temperature of the outer air to be provided for, D is the known external diameter of the pipe, T the temperature of the pipe and L the length of the pipe required. Water heating is sometimes accomplished at a temperature intermediate between those of the low-pressure and high-pressxne systems. A pressure Fig. 247.— Elevation of Pipe System Usually Employed in Steam-Heating. (Alter Baldwin.) not exceeding two or three atmospheres is used, corresponding to about 265° F. When this pressure is exceeded, it is automatically relieved by a valve; the diminished pressure operating another valve by which the proper amount of cold water is admitted into the system. Heating by Steam. — As water is a much better agent than air for the absorption and transmission of heat, so is steam superior to water for the same purpose, since the amount of heat maintained by it in a latent condition is very great. One pound of steam at 212° F. will, in condens- ing to form boiling water, give off sufficient heat to raise the temperature of 5.36 pounds of water or 22.5 pounds of air to 212° F. In its essentials the steam-heating system comprises a steam generator or boiler, pipes for the distribution of the steam, condensers in which it may return to water and give up its heat, and finally, pipes for the return to the boiler of the water of condensation. The operation of the system depends upon the fact that steam travels through a closed system over great distances with great rapidity, and without condensation provided the pipes are of sufficient calibre and are properly insulated. The return to the boiler of the water produced by its condensation is accomplished by gravity. The pipes carrying the steam to its destination are of smaller bore than HEATING AND LIGHTING. 519 are used with the low-pressure hot-water system, usually having an inter- nal diameter of about 1.5 inches. If the buildiag to be heated is large, however, and the steam is to be conducted a considerable distance, the interior diameter of the distributing pipes must be proportionately in- creased. Thus at Washington Barracks the heating system in one of the barrack buildings was a failure during very cold weather, since the dis- tributing pipes were too small and condensation of the steam occurred be- fore it reached certain of the rooms which it was intended to warm. In addition to ensuring that the distributing pipes are of sufficiently large bore, they should be iasidated as much as possible during their course by wrappings of felt or asbestos cloth. For the latter purpose the Ambler asbestos air-cell covering is excellent. The covering is composed of divided air-cells, each independent of the other, produced by arranging in alternate layers sheets of plain and cor- rugated asbestos paper, woimd into cylinders of proper diame- ter. These cyhnders are split longitudinally so that they can be easily shpped over the pipes. The covering is light, neat, non- conducting, fireproof and not liable to deterioration. The radiating pipes are made of at least four times the diameter of the conducting pipes, so as to ensure efficient condensation ; and if of copper or cast iron, and colored some dark tint, they radiate heat more rapidly. Since in steam-heating the pressure is usually not more than 1^ atmos- pheres, the pipes need not be as substantial as with high-press- lu-e hot-water heating. Multi- tubular steam boilers merit pref- erence over more simple types ; since, independent of the security they give, they permit of much greater rapidity in the production of steam than with other boilers. In the United States, to provide for aU emergencies, it is customary to allow one square foot of heating surface in the boiler to five feet of radiating surface. Aside from its use for heating purposes, in foreign barracks the steam-heating system, when in operation, is generally utilized to supply hot water for the lavatory and laundry. In the German army, nearly all the cooking of the ration is done by means of steam from this source. The size of steam radiators is obviously dependent upon the amount of heat required. A number of elaborate methods for calculation of the amount of radiating siurface necessary have been proposed, but the results given by these are, in practice, no more satisfactory than the common rules of thumb, based on long experience, which are used by steam-fitters. For the United States at large, to heat to 70° Fahrenheit with an outside tem- perature of zero Fahrenheit, the general rule is to allow one square foot of Fig. 248.— Section of Boiler for Steam-Heating, Showing Amount ol Water Surface Exposed to tlie Heat. 520 THEOEY AND PRACTICE OP MILITARY HYGIENE. radiating surface to each 75 cubic feet of space. Another rule is to allow one square foot of radiating surface to each 100 cubic feet of space, with an increase of radiating surface as follows : Ten per cent, when the exposure is a northerly one ; ten per cent, when the buildiag is heated duriag the day only, the location not beiug particularly exposed; thirty per cent, when the building is heated during the day only, and the location is an exposed one ; fifty per cent, when the building is heated intermittently, with intervals of days or weeks of non-heating. For the climate of Washington city, a common rule is to divide the cubic capacity of the room to be heated by the number 80 ; corrections for special exposure being made as above. For cold climates. Mills gives the following rule : Allow one square foot of radiating surface for each two square feet of glass, one for each twenty square feet of exposed wall and one for each two hundred cubic feet of space. The sum gives the number of square feet of radiating surface required. Another rule for indirect heating, to maintain a temper- ature of 70° F. inside with an outside temperature of zero, the surface of the steam radiator being taken at 212° F., is to add the number of square feet of glass to one-fourth the exposed wall surface in sqiiare feet, multiplying the sum by the factor 0.7. The result gives the number of square feet of radiatujg surface required. Clearly there is no one rule which would apply to all cases of building construction and all exposures, and hence considera- ble dependence must be had upon judgment and the results of experience. One great advantage possessed by steam-heating in this connection is that miscalculation in the si^e of radiators and pipes, if not excessive, can be overcome by increasing the pressure of the steam. Steam-heating is now used in a large proportion of the barracks which have been erected during the past decade, particularly those located at the colder stations. It is also much used in foreign services; more especially for hospitals, but also to some extent for barracks. When steam-heating is used there is no direct contamination of the air, but in a close apart- ment the indirect contamination, from failure to remove the respiratory impurities, is serious — the same air being warmed and breathed over and over again. Hence special means of ventilation, as with hot-water heat- ing, must be provided. This is usually accomplished by the direct-indi- rect method, which gives most satisfactory results. With steam heat the air is not scorched, since the floating particles are not heated above 220° -225° F., the conduits and radiators are small and the heat is readily controlled by manipulation of the fire or of the radiator valves. The sys- tem is devoid of danger, since a pressure of one and one-half atmospheres, corresponding to a temperature of about 235° F., is rarely exceeded. While in operation, steam-heating gives a uniform temperature. There is, however, no reserve of heat, and when the fire is lowered the heater ceases to act and the apartments cool down rapidly. To avoid this, at the military hospital at Vincennes, in France, a system has been installed which includes large tanks of water imder the floor, through which steam pipes are made to pass. These raise the temperature of the water, which thus becomes a reservoir of heat. After passing through the water the steam is conducted into condensing pipes, whence it returns to the heater. A defect which may be present in a badly arranged steam-heating sys- tem consists in the violent pounding sometimes noticed in the pipes. HEATING AND LIGHTING. 521 This is due to water accumulating to such an extent as to condense some of the steam in the pipe ; thus forming a vacuum which is fiUed by a very violent rush of steam and water, the latter striking the side of the pipe or radiator with great force. In general, this may be prevented by arranging the piping in such a manner that the water of condensation will immedi- ately drain out of the radiators and pipes and return to the boiler. The common system of steam-heating provides a special set of return pipes for this purpose. As steam diffuses slowly and does not condense rapidly in a space occupied by air, it is necessary to let the latter escape from the pipes and radiators at the time the steam is turned on. This may be done by hand, but is best accomplished by valves of composition metal which are open at ordinary temperatures and close by expansion at the temper- atin'e of steam. These again open and admit air automatically if the fire is allowed to die down. II. LIGHTING. In addition to an abundant and constant supply of pure air, the entrance of sunlight into barracks is a matter of much sanitary importance. This can be secured by a proper architectural plan and orientation of the build- ing, a sufficiency in number and size of windows and doors, and by locat- ing the building in such a manner that its sunlight will not be interfered with by trees, buLldings or other objects. Porches of too great depth may be. a cause of undue shade, and an insufficiency of light is favored if these are painted in somber colors. For the inside of porches and barracks the best results, all things being considered, is given by painting in light yel- lows or cream color. Pure white absorbs luminous rays least, but it also shows defacement readily and gives rise to a trying glare in direct sunlight. An abundance of natural light in barracks, aside from its obvious necessity for the proper performance of administrative functions, exerts a marked in- fluence upon the efficiency of the sanitary police. Dark, illy ventilated recesses are especially liable to shelter unsightly and unsanitary accumula- tions, which would never be allowed to exist were they exposed to ready inspection; while even with the best intentions minor sanitary faults are easily overlooked under such conditions. Light, also, particularly direct sunlight, is unfavorable to the growth of pathogenic micro-organisms, none of which can long survive exposure to the solar rays ; and the free access of an abundance of natural light into barracks should be regarded as essen- tial to their healthfulness. Deficient sunlight also unfavorably influences physical development and undoubtedly is a factor in the production of mental depression. In many of our older barracks, and necessarily so with casemates, these matters have been disregarded ; but in the newer bari'acks natural lighting has received satisfactory consideration. In determining the number of windows required for the proper natural lightiag of barracks, the number of days of sunshine which may annually be expected in a post should receive consideration ; and in cold climates the window area must not be made too large. Putzeys believes that, for temperate climates, it will suffice if the window area is equal to one-sixth or one-fifth of the floor space — or one square yard for each thirty cubic yards 522 THEOEY AND PEACTICE OF MILITARY HYGIENE. capacity. Trelat goes further, and believes that the window area should equal one-fourth the floor space, or should be calculated on a basis of fif- teen square feet per man. It is obviously desirable, in temperate climates, that direct sunshine should reach all parts of a squad-room. Even if win- dows be made ten feet high, the solar rays cannot strike the floor, if enter- ing at the desirable angle of 35 °-40°, for more than half the width of a squad-room twenty-five feet wide. Hence windows on both sides of a squad-room are necessary to the accomplishment of this end. The amount of light which can pass through such windows depends to a considerable extent upon the quaKty and character of the glass. Galton showed that ordinary window-glass intercepted thirteen per cent, of light, ground glass thirty per cent., and heavy corrugated glass fifty -three per cent. Dust ap- pears to adhere less readily to glass of good quaKty and smooth finish. With respect to artificial lighting, that of our posts and barracks is a matter of much importance; of posts, not only because such lighting is a general convenience but particularly since it is a potent meansof restrain- ing the perpetration of nuisances in the vicinity of barracks — such being especially liable to be committed under cover of darkness. The number of lanterns and street lamps for the illumination of a post, outside of barracks, . is fixed by the department commander. In bundings used as habitations the heat and atmospheric vitiation re- sulting from artificial lighting are worthy of careful sanitary consideration. This matter has received little attention in our service, and lighting is still accomplished in nearly all barracks and hospitals by the most primitive methods, such as have long since been discarded in nearly all large insti- tutions in civU life. In the matter of lighting, our soldiers are by no means as well treated as are the inmates of asylums and prisons. Candles are sup- plied as one of the components of the ration, but are rarely used except in the field. Coal-oil is used for illuminating purposes in nearly all garri- sons ; but at a few posts, near large cities, connection has been made with the municipal gas mains. In several of the new artillery stations, in which electric plants had already been installed for other purposes, electric lighting has lately been authorized in the barracks now under construction. Unit of Light. — In this country and England, the unit adopted for the measurement and comparison of lights is a sperm candle of the size known as "sixes," burning eight grams per hour and giving out a light known as ''one-candle power." Such a candle, on .analysis, contains: Carbon 80 per cent. Hydrogen 13 " Oxygen 6 " and in combustion yields equal volumes of carbonic acid and watery vapor to the air, namely, 0.41 cubic foot. The French unit "of light is the Car- cel burner, which equals 9.3 standard English caudles. Mineral Oil. — Although various kinds of oil have been employed for illuminating purposes, mineral oil, owing to its cheapness and high illumi- nating value, is the only one used in the military service. Analyses of this oil, according to Notter and Eirth, give the following average com- position : Carbon 86 per cent. Hydrogen 14 " HEATING AND LIGHTING. 523 When burned in the better kind of lamps, the average consumption of this oil, per candle power, is four grams per hour, giving off at the same time 0.28 cubic foot of watery vapor. With inferior lamps the consumption of oil is often double this amount, accompanied by the production of 0.5 cubic foot of cai-bon dioxide and the consumption of the oxygen of about 3.2 cubic feet of air. In our m i litary service, for stations where mineral oil is used, an excel- lent Eochester-burner lamp of 55 candle-power is issued. One of these burners is allowed to each ten men, or greater fraction thereof, and an al- lowance of four ounces of oil is authorized for each hour during which the light may be maintained ; a matter regulated by the conunanduig officer of the post with the approval of the department commander. The above al- lowance does not represent the maximum burning power of the lamp but is sufficient to produce a fair light. A number of small bracket lamps, single and double, are also still in use, though no longer supplied for issue. These have a lighting capacity of 18 candle-power and are expected to consume two ounces of mineral oil per hour. The light produced by these lamps is neither powerful nor of the best quality, the expense of their operation is great and they require constant care and atten- tion. The amount of time spent in properly caring for the lamps used in our service is, in the ag- gregate, very great — and furnishes a strong economical argument against the use of such means of illumination. The vitiation of atmosphere by the products of their combustion is also large, and flaring, with its smoke and sooty deposits, is liable to result from any gust of air. In warm cli- mates or sununer weather the heat which such lamps evolve often renders the temperature of barrack-rooms almost insupportable ; besides which they are never free from danger of fire or explosion as a result of accident or a poor quality of oil. Coal-gas. — This is used for purposes of illumination in a few posts located in the immediate vicinity of large cities, the supply being derived from the local mains. Usually it happens, however, that even under con- ditions when gas might be obtained the garrison is required to use mineral oil, much to its unnecessary disadvantage. Coal-gas, as its name impKes, is a mixture of a number of gases pro- duced in the dry or destructive distillation of coal. About ninety per cent, of coal-gas is made up of so-called diluents, which do not give much lumi- nosity but dilute the heavy hydrocai'bons, which might otherwise give a smoky flame. These diluents are chiefly hydrogen, methane and carbon dioxide. The actual illuminants, constituting only about six per cent. , con- sist of gases rich in carbon, as ethane, acetylene and defiant vapor. The impurities make up the remainder. Every cubic foot of ordinary coal-gas Fig. 249.— Barrack Lamp. 524 THEOEY AND PRACTICE OF MILITARY HYGIENE. yields, on combustion, roughly half its own volume, or 0.52 cubic foot, of carbon dioxide and 1.34 cubic feet of watery vapor. Knowing the quan- tity of gas which each burner consumes hourly, the average in our service being six cubic feet, there is therefore no difficulty in calculating the vitia- tion of the air from such causes. Combustion, however, with ordinary burners is never complete ; thus slight traces of carbon monoxide will gen- erally escape combustion, while with a rich gas distinct traces of acetylene are generally given off. The actual products of combustion vary with the quality of the gas and the completeness of the process. AVhen coal-gas is partly burned, the hydrogen and light and heavy carburetted hydrogens are almost destroyed. Of the resultant, nitrogen constitutes about sixty-seven per cent. ; water, sixteen per cent. ; carbon dioxide, seven per cent. ; and carbon monoxide, five to six per cent. A small amount of sulphur dioxide and ammonia are also found. Where the combustion of coal-gas is perfect, there will be little production of carbon monoxide. Speaking generally, it may be said that each cubic foot of gas burnt per hour from ordinary flat burners vitiates as much air as would be rendered impure by the respirations of an individual during the same period. The complete combustion of a given volume of coal-gas must, on theoretical grounds, give rise to the production of exactly the same products of combustion in whatever burner the gas is con- sumed. It follows, therefore, that if the consump- tion of gas be low, the evolution of gaseous im- purities will be proportionately reduced ; so that, apart from mere questions of economy, a burner which consumes a relatively small amoimt of FIG. 350.— Argana Burner. gas, to Say nothing of the superior light it may give, must be preferable on that account from the sanitary point of view. The relative hygienic advantages of certain bur- ners are therefore weU worthy of consideration. The most simple gas-burner is the common pattern giving a flat, but- terfly-shaped flame. This is the burner employed wherever gas is used ia our barracks, and, as supplied, is capable of burning six cubic feet of gas hourly. Its illuminating value is 16 candle-power. This burner has many bad qualities, especially for the interior lighting of barracks and hospitals. The light is unsteady and trying to the eyes and the flame is also liable to smoke in air-currents. The latter may, however, be pre- vented and the light softened by the use of globes. The amount of gas used is proportionately large and its combustion is not complete, thus causing great vitiation of the atmosphere of the room. The quantity of heat developed by the combustion of gas in burners of this character is also very great. These defects are fully appreciated in civil life, and dur- ing the past few years various gas-burners have been introduced which not only increase the luminous intensity of combustion but also diminish the consumption of gas, while special arrangements decrease the vitiation of the air. While many varieties of these burners have been devised, the Argand burner, the Wenham regenerative burner and the Welsbach burner are probably the best representatives of theii- types. HEATING AND LIGHTING. 525 Fig. 251.— Wenham Regenerative . Burner. The Argand burner is a great improvement over the ordinary flat burner, consuming less ^as and at the same time yielding more light. In this contrivance the gas escapes through a series of small holes disposed in a circle around an annular burner, itself surrounded by a cylindricaL glass or globe. The combustion of gas is more complete by this method than with the flat bur- ner and the flame is more steady. The gas ar- rives at the burner under a low pressure ; some modifications of the apparatus possessing an au- tomatic pressure regulator. Burners of regeneration are based on the principle that Uluminating gas bums better, is more completely consumed and produces a stronger light if it is mixed with very hot air at the moment of combustion. For the 'attainment of this object, the heat of combustion is used to elevate sufficiently the temperature of the cold air entering the apparatus. In the Wenham burner the most important part is the cylinder B, through which small pipes serve for the entrance of air, while the heat and gases of combustion escape through intermediate pipes to pass out at A.. To light the burner the globe D is removed. The flame must be kept low at first, since otherwise the glass is liable to be shattered. The burner gives a steady white light and is very economical of gas. By its use there is not only Kttle or no vitiation of the atmosphere in the room, but when in op- eration the apparatus promotes ventilation by acting as an efficient heat- extracting shaft. This type of burner is excellently adapted for use in baiTacks where gas is employed. Of the various forms of light derived from coal-gas, that yielded by the Welsbach burner stands out pre-eminently as the best. This bixrner, when complete, may be said to consist of two essential parts. The first is an ordinary but carefully adjusted burner of the Bunsen type, in which air and gas are mixed before combustion ia the proportion of thirty parts of gas to sefventy of air, producing a colorless or faintly blue flame. The second part is a fine, gauze-like mantle composed of nitrates of the alkaline earths, ce- rium, lanthanum, thorium and zirconium, which is sus- pended in the flame by a forked support of magnesium silicate, itself luminous when hot. The flame and man- tle axe enclosed in a glass chimney, which serves to protect the fragile mantle from accident and also to keep the flame steady. The principle of the Welsbach burner depends upon the conversion of heat into lumin- ous rays, the mantle being rapidly raised to incandes- cence by the heat of the burning gas. The light given by this burner is very white, brilliant and steady, being much like that of the electric light. This apparatus consumes only about half the gas re- quii'ed for combustion by an ordinary flat burner, while at the same time it gives off more than three times as much light. The mantles are some- what fragile and are said to last only 800 to 1,000 hours. Their increased Fig. 352.— Welsbach Burner. 526 THEORY AJS"D PEACTICE OP MILITARY HYGIENE. cost in this respect, however, is more than made up by the very great sav- ing of gas thus rendered possible; but this fragility is none the less a seri- ous drawback for the use of these burners in barracks, where they may be subjected to less careful usage. In hospitals, where gas is provided, this pattern of burner should always be supplied. Acetylene. — This gas, from its many admirable qualities as an illumi- nant, its readiness of preparation, ease and safety in handMng and the small si^e and comparatively light weight of the simple apparatus used in its generation, is especially suited to the needs of the military service. Tar superior to candles, oil or coal-gas, it is probably surpassed, from the sani- tary standpoint, by the incandescent electric light alone. Acetylene is a pure hydrocarbon gas, having the chemical formula CjHj. It is produced from calcium carbide by the addition of water in excess, according to the following reaction : CaO, + 2H,0 = Ca(OH), -f C,H,. One pound of calcium carbide, to which nine ounces of water have been added, wOl yield six and one-half ounces of acetylene gas — or about five cubic feet. This gas is clear and colorless, has a distinctive odor resembling garlic and burns with a flame of intense brDliancy, the spec- trum being almost identical with that of the sun. Acetylene is the chief illuminating principle of ordinary coal-gas, though present in the latter Fig. 253.— 4, Acetylene, one-half-foot burner; B, . ,, ? j^ i j_ n ^ Gas, six-foot burner. Photographic exposure of m the proportion 01 but lOUr to SIX three seconds. ^^^ ^^^^_ It is a permanent gas under the low pressure in which it is used, and when mixed with air in about the same proportions as coal-gas it acts in a similar manner and may be stored, handled and distributed in the same way. A certain prejudice has existed against acetylene from accidents which followed its use in the early form of generators ; but modern apparatus entirely eliminate aU dan- ger of use. Calcium carbide, however, should be kept in water-tight metal cans when stored, and should not be -exposed to the weather. Mixed with air, acetylene appears to be no more explosive than is coal-gas ; and when escaping from leaky joints it may be safely lighted, this being the usual method of locating imperfections in distributing pipes. Fatal asphyxiation appears to be much less liable to occur with acetylene than with ordinary gas. The quality of the light given by acetylene is excellent, being clear and white and strongly resembling that given by electricity. The light is also very intense and steady; far surpassing coal-gas, as used in ordi- nary burners, in these respects. Calcium carbide is now made in vast quantities, and at slight expense, by fusing calcium and carbon together in the electric furnace. A 25 can- dle-power burner, which consumes but one-half a cubic foot of acetylene per hour, costs for its operation about two-fifths of a cent hourly, which is less than that of operating a 6 -foot flat gas-burner and about the same as the electric light under the conditions usually found in this country. The price of calcium carbide, moreover, is steadily falling as a result of more economical methods of production. Eecent investigations made in HEATING AND LIGHTING. 527 France by Hospitaller, comparing the cost of acetylene with other illumi- nants, expressed in cents and terms of one candle-power for one horn', gave the following results : lUumlnant. Cost in cents. muminant.1 Cost in cents. Tallow candle 4.00 .76 .6 Petroleum Gas, Welsbach burner .54 Gas, open burner .33 Edison, incandescent .2 The scheme of operation of modern acetylene generators is extremely simple and merely requires the automatic control of contact between the carbide and water. These generators are divided into two main forms ; one in which the water is fed to the carbide in small quantities, and the other in which the carbide is fed to the water. The first form of appa- ratus is not without danger and is wasteful of gas. The second form ap- pears to be largely free from defects and is compact, readily operated and free from danger. An acetylene generator capable of thoroughly lighting a company barrack or post hospital need not be greater in bulk than a hogshead, while one capable of illuminating a field hospital of one hundred beds is not larger than a pork barrel; the latter apparatus weighing when complete, without water or carbide, but little more than one hundred pounds. These generators are thus very transportable and are capable of excellent use in hospitals and headquarters offices in the field. In per- manent buildings, acetylene is distributed by ordinary gas-pipes ; but in the field rubber tubing may be used, this being rapidly strung from one hospital tent to another — when several tents are pitched together — below the ridge-poles. A special burner is required for the combustion of acety- lene, in which a flat flame is produced by the reciprocal action of two tips. If the gas be moist, carbonization is liable to occur on these tips, which should therefore be frequently inspected. Usually combustion of the ace- tylene is complete, and an object, such as a white plate, shows no trace of soot when held in the flame. Acetylene generators are made in an almost infinite number of varieties and sizes, according to the special purpose for which they are intended. For barracks and post hospitals, an apparatus hav.ing a carbide capacity of twenty-five pounds and capable of supplying illumina- tion at the rate of one 25 candle-power burner for 250 hours will usually be sufficient. To ascertain how long such a generator will supply the number of burners de- sired, it is only necessary to divide the number of hours of service by the number of burners required. Thus with an apparatus like the above, fifty burners may be burned simultaneously during a period of five hours — but usually only a small proportion of the burners provided would be used for the same period. In a Colt acetylene generator used in a barrack-building at Washington Barracks, containing forty-five men, re-charging of the apparatus was nec- essary but once every three days. This form of generator is simple in the extreme, consisting of only three principal parts : First. A water-supply tank, holding only sufficient water for genera- FiG. 254. — Burner for Acetylene Gas. 528 THEORY AND PEACTIGE OP MILITAEY HYGIENE. tion and for keeping the residue in a liquid state; the supply of water being inserted and the residue drawn off without the use of stopcocks or valves and without opening the generator, no gas escaping and no air being admitted. Second. The carbide holder, having a conical bottom secvired over the water supply and provided with a carbide feeding-valve of simple and positive action. Third. A gas-beU to enclose the carbide holder and to connect it with the water-supply tank, separately water-sealed. The gas-beU regulates the feeding of the carbide from the carbide holder, and is so arranged that the latter can be fill ed without removing the bell and without the escape of gas or admission of air. Incidental to the generator proper is an improved blow-off. Any sol- dier of ordinary intelligence can re-charge one of these generators in a few minutes. The residue is of a creamy con- sistency with practically no odoj and can be poured into drain pipes or sewers. This residue, being nothing but thick milk of lime, is obviously an excellent disinfectant. Where a sewer connection is convenient, the residue flush-out pipe of the generator may be connected with it and the appara- tus filled with water by means of a bucket, or, if a water service is convenient, it may be connected so that by opening a faucet and allowing the water to run through the machine the latter cleans itself; so that absolutely no other attention is necessary except to open the filler-cap and pour in a fresh supply of crushed carbide. If no sewer connection or water service is con- venient, the cleaning out of the machine is done by putting a bucket under the flush- out pipe and pouring water into the bib. The amoimt of residue to be handled is re- duced to a minimum and the method of doing it is simple in the extreme. As the gas is entirely extracted from the residue, no odor of acetylene escapes into the room. A small portable generator, when packed similar in shape and size to an ordinary water-pail, having a carbide capacity of two pounds and main- taining four 25 candle-power burners for four hours, possesses particular value for use in the field, for offices or operating-tents. For cleaning and charging only a few minutes are required, and, like the larger forms of generator, during operation this apparatus requires less attention than an ordinary mineral oil lamp. Electricity. — Of all the systems of lighting in common use at the present time, the incandescent electric light must be regarded as by far the best from the standpoint of health. The light is very pure, steady and of great intensity ; and is especially valuable for military use because of the slight amount of heat which it gives off, and from the fact that with Fig. 255.— Large Size Acetylene Genera- tor. HEATIXG AND LIGHTING. 529 its employment no deleterious products of combustion are passed into the atmosphere of the room nor is the oxygen of the latter drawn upon for its successful operation. Electric lighting is, however, somewhat costly, and re- quires a special plant and trained mechanical supervision for its production. For these reasons it may not be possible, from motives of economy, to in- stall this method of lighting in small posts, especially if these be of a presumably temporary character. In many large garrisons, however, engines are used for pumping up the water-supply and steam is kept in these engines at night in anticipation of possible con- flagration. In such posts, dynamos could be driven at night by these engines with but slight original outlay, a constant saving to the government and much benefit to the garrison. In the past, repeated efforts to obtain authority to utilize power thus wasted has met with no encouragement from the authorities. Not long since, a former head of the responsible de- partment, in refusing such a request, although shown that by this means an actual saving to the govern- ^ „„ . „, •' n^ ■ T, 1, 1 ■-,.■, ^'<5- 256.— Acetylene Gen- ment would result, onicially stated that electric light- erator, smau size. ing was stiU in the experimental stage — and this in spite of the fact that outside the military service electric lighting was every- where being successfully employed to the comfort and advantage of aU con- cerned. For this non-progressive attitude there can be no justification, and it is to the credit of succeeding authorities that such a mistaken policy has not been persevered in. As already mentioned, within the past few months certain stations have been equipped with electric lights, and it is much to be hoped that this system of lighting may be introduced into aU our posts of any size or permanency. Particularly is this the case with reference to the southern garrisons, in which coolness of barracks is of great importance and where the universally open doors and windows permit of free drafts which cause smoking and flickering of the flame from burning gas or oil. For hot climates or summer weather, it should not be forgotten that the greater or less amount of heat resulting from artificial Ulumination means all the difference between comfort and discomfort. Illumination by electric arc lights is obviously not desirable for bar- racks, though these are excellent through their penetrative power for the lighting of posts. The light from the electric arc is too intense and is very unstable, while the consumption of the carbon is accompanied by a constant buzzing sound. Such lights, which are not contained in sealed glass globes, ^re said to vitiate the air ia the formation of nitric acid. This, however, is of no importance in connection with the circumstances under which such lights should be used ; and imder any conditions their effects in this direc- tion are proportionately much less hurtful than the combustion of coal-gas, oil or candles, as now supplied. Vitiation and Heating of Air. — From a sanitary standpoint, these matters are of chief importance in the lighting of buildings ; and the fol- lowing table well shows the relative standing, in these respects, of the more common means of illumination : 34 530 THEOEY AND PEACTICE OF MILITARY HYGIENE. Method of lUumlnation. - ?? i Ill 1 COj Moisture 3^ Bi sis o 1 produced. .produced. n 147 grams 16 10.7 7.3 cu. ft. 8.2CU. ft. 1,400 116 " 16 9.6 6.5 " «.5 " 1,137 60.6 " 16 5.9 4.1 " 3.3 " 1,030 5.5 cu. ft. 16 6.5 3.8 " 7.3 " 1,194 4.8 " 16 5.8 3.6 " 6.4 " 1,340 3.3 " 33 3.6 1.7 " 4.3 " 760 3.5 " 50 4.1 1.8 " 4.7 " 763 1.0 " 50 2.0 " 0.3 lb. coal 16 0.0 0.0 " 0.0 " 37 0) OJ 5 m ■Sa Tallow candles Sperm candles Kerosene lamp Coal-gas No. 5 " batswing ' burner Coal-gas, Argand burner Coal-gas, regenerative burner. : Coal-gas, Welsbacli incandes- cent burner Acetylene Electric incandescent lamp 13.0 11 7 5 4.3 2.8 3.6 0.0 With respect to vitiation of the air, it is evident that the incandescent electric light, which exerts no deleterious effect whatever upon the atmos- phere, is easily to be given the first rank. Comparing other methods of illumination to this respect, after reduction to a common standard in can- dle-power, it is seen that the Welsbach incandescent Kght and acetylene gas give very similar results ; the vitiation of the air from the flat gas-bur- ners and kerosene oil-lamps used in our service being respectively about five and seven times greater than these. The heat produced by the two last- named methods, proportioned according to the light given, is thirty to thirty-five times greater than that resulting from the use of the electric in- candescent lamp, while with the regenerative gas-burner the heat produced is ten times greater. The heat produced by acetylene is said to be only one- tenth that of gas when burned in an ordinary flat burner. Investigations made by the writer, at Washington Barracks, showed that of two large bar- rack rooms of identically the same si^e and construction and number of illuminating burners, but one of which rooms was lighted by coal-gas while the other was lighted by acetylene, the temperature on a warm evening in May was 7° F. higher in the room lighted by gas than in the one lighted by acetylene — both rooms having been tightly closed with aU jets burning for one hour. Where lUuminants other than electricity are employed, deterioration of the air of the room, resulting from their use, can be largely prevented by placing above the burners small flues with wide, beU-shaped extremities to carry off the gases of combustion into the external air, the heat of the burners producing strong currents of air outward. Eichard recommends that, when gas is to be burned in the air of a room, the small flues opening over the gas-jets should run to the chimney and discharge into a special air-shaft in the latter. This air-shaft should be of a size capable of remov- ing (1) the volume of gas burned; (2) the volume of air necessary to burn the gas — about four times the volume of the latter — and (3) a quantity of air, in addition, which he estimated at two hundred times the volume of the gas burned. Unfortunately, such an arrangement, though good, is not especially easy of installation in barracks and is somewhat costly, and can therefore in practice be largely left out of consideration in dealing with the question of the vitiation of air by lights. The removal of the HEATING AND LIGHTING. 531 products of combustion by the regenerative burner, as already described, is excellently accomplished. Conclusions. — It is evident from the foregoing that, considered prac- tically as well as hygienically, illumination in the military service — under all circumstances, but especially for stations in warm climates — should be accomplished wherever possible by means of the electric incandescent light. Considerations of hygiene, comfort and economy, taken together, also point to the use of acetylene in aU posts where electric lighting cannot be secured. The small amount of heat and atmospheric deterioration result- ing from the combustion of acetylene render this illuminant much superior to coal-gas as commonly used, especially for hot climates. As compared with mineral oil, acetylene is far superior in all respects, Por isolated stations or buildings it possesses special advantages, while the compactness and ready portability of the acetylene generators and distributing pipes render it especially available for stations of no great permanency or for certain purposes with troops under canvas. It is much to be hoped that the responsible authorities in our service may give this method of lighting the favorable consideration which it deserves. In stations where coal-gas has already been introduced an-d cannot be exchanged for electric lighting, it is equally clear that the flat "bat's-wing " burners should be discarded; and regenerative burners used in barracks, while Welsbach burners are preferably to be employed in hospitals. Ordi- narily, however, where coal-gas can be obtained, electricity can also be supplied and at no greater cost. Mineral oil should be totally discarded as an Ulmnuiant for barracks and hospitals, under all circumstances. In view of the far better method of lighting available in the use of acetylene, this can now be done at slight original outlay and with decreased running expenses. For the lighting of small detached buildings not employed for the shelter of troops, mineral oil may be still allowed a limited use. Candles shordd be employed by troops only when in the field, as is practically the case at present. CHAPTER XII. DISPOSAL OF EXCRETA, SEWAGE AND EEFUSE. In the military service, the removal of excreta from the vicinity of habitations is of even greater sanitary importance than is the case in civil life. It has already been noted that where troops are constantly changiag their residence site, as during campaign, they will not usually experience the consequences of inefficient removal of excrementitious waste; since instead of the excreta being removed from the troops, the latter are con- stantly being moved away from their excreta. In large standing encamp- ments, however, the disposal of such material becomes a serious sanitary problem, directly dependihg in its gravity upon the relative permanency of the camp. In camps intended for long occupancy, as with fixed posts, the proper disposition of material of this character becomes literally a matter of life and death. The military sanitarian will therefore endeavor to se- cure its removal from the vicinity of buildings and posts; not only promptly, but also in such a manner that neither air, soil nor water shall be made impure and no opportunity shall be left for the occurrence of dis- ease from any infectious material which it may contain. Clearly these theoretical requirements are not easily to be satisfied, and their accom- plishment may be secured only by the expenditure of much labor and con- siderable financial outlay. For these reasons, the most efficient methods of disposal have not always been introduced into our posts during the past, particularly since many garrisoned stations were recognized as not being of a permanent character and maintained only to meet a temporary military exigency. With the abandonment of posts of the latter charac- ter, the general conditions with respect to the disposal of excreta and liquid refuse have undergone a steady improvement throughout the service. At present, the methods of disposal of excreta and liquid wastes in our permanent posts may be classified somewhat as follows : A very few small frontier stations stiU in the primitive sanitary condition of privy-pit con- servancy, with no provision for the disposal of liquids save the absorb- ing soil of their sites; a few in which earth-closets have been substituted for the pit system; a few in which, besides the earth-closet or the pit, some effort is made for the removal of liquid wastes ; a few in which the drains for these liquid wastes form the rudiments of a sewerage system, by having connected with them the outflows from certain lately introduced water-closets; and lastly, the great majority provided with thoughtfully planned, carefully built and thoroughly efficient systems of sewerage. As a whole, our methods of disposing of excreta and refuse compare very favor- ably with those of foreign armies, particularly in those of France, Eussia, Italy and Spain, in which the disposition of excreta is frequently of such character as to furnish a continual menace to the welfare and safety of troops. DISPOSAL OF EXCRETA, SEWAGE AND REFUSE. 533 The Cess-pit System. — Until a comparatively recent period, exca- vated pits or vaults afforded the most common means of disposing of the excreta in posts. These pits were usually deep and roughly stoned, and ultimately contained considerable quantities of putrescent and offensive matter ; this giving rise to gases and liquids that only too readily polluted the air and soil around them, contaminated the ground-water and pene- trated to the wells in their vicinity. The distance through which the latter action might be exerted, as already mentioned, was often consider- able, depending upon the difference in depth between the privy-vault and tlie well, the character of the soil and the direction and rate of movement of the subsoil water. The cess-pit had also the defect of requiring the ex- posure of the person over a large excavation full of cold and mephitic gases ; a condition which, particularly at night, may predispose to disease in the partially-clad soldier. Further, the conditions in such vaults were usually very favorable to the development and increase of many pathogenic micro-organisms. An attempt was sometimes made to limit the genera- tion of odors by the application of earth or ashes, but these materials filled up the vault so rapidly that their use was ordinarily not long con- tinued. Disinfectants were also sometimes employed; but only rarely, as they were not usually available for such purposes. When filled up, such vaults were rarely emptied, but were covered over and left unmarked and forgotten to remain as dangerous hidden foci of disease to future garrisons. The worst offenders in this respect were the common shallow pits dug for temporary relief, generally without authority, near the stables, corrals and married soldiers' quarters, frequently honeycombing the site of an old post. Thus it was reported from Fort Leavenworth, in 1899, that the ground around the married soldiers' quarters was so full of abandoned latrine vaults that it was difficult to find a site for a new one ; in an effort to this end, six excavations had to be made before a spot was found which had not previously been used for this purpose. At old Fort Omaha, lately abandoned, privy-pits had been dug and filled so often that the soil was everywhere saturated with faecal matter, and the ground-air so foul as to be a cause for complaint. The cess-pit system of disposal was until re- cently in use at Fort'Keogh; the post area having in the course of time bec(jme thickly studded with deposits of filth. Of Fort Washakie, it was reported several years ag& that the soil was so honeycombed with privy vaults that no new cess-pit could be excavated in the hospital yard with- out opening old ones. These instances are cited to show the nuisance which the privy-pit system ultimately produces. While this method of disposal may temporarily be relatively inoffensive, it is only a question of time when it will exert a most unfavorable effect upon the healthfulness of the site. Aggregations of filth of this character long preserve their original characteristics and are only slowly disintegrated by bacterial action, for the reasons detailed in connection with the bacterial treatment of sewage. Usually a privy-pit which has been once installed, even if originally intended for temporary purposes only, is continued in use untO. the un- sanitary conditions produced by its existence compel its abolishment. Hence the establishment of privy-pits, under any such pretext, is to be firmly opposed by the sanitary officer. Should higher authority decide to 534 THEORY AND PRACTICE OF MILITARY HYGIENE. permit their use, at least they should be specifically designated as to place and depth, iilled in according to rule and marked both in place and on the post map. At permanent posts, where such old pits are known to be in existence, if close to any occupied habitation they should be reopened, emptied, limed and filled with clean earth. Wherever their use is permitted they are best cemented inside so as to be water-tight, should be disinfected, at short intervals and should be pumped out frequently by odorless exca- vating apparatus. The vault should be roofed in and well ventilated by long flues running through the roof ; the ventilating shafts being preferably painted black. The movement of the foul air in the vault is thus rather outward by the ventilating flues than by the apertures in the seat. At present, even in some of the most important posts, the married en- listed men's quarters are dependent upon privy-pits for the disposal of excreta. This arrangement should be done away with; water-carriage should be provided if possible, and iu its absence the earth-closet system should be installed. The vault system is still in use in several foreign armies, and under special conditions which render it much more offensive and unsanitary than is the case in the few instances in which it is still employed with us. Thus in several barracks in Paris, it is stated that immense cess-pits have been excavated beneath the buildings ; sometimes these are cemented inside, but often they are so cracked as not to be water-tight and to permit their fluid contents to soak into the surrounding soil. This method of removal, however, appears to be not always regarded, by certain minds, as undesirable, since sanitary cleansiug is an offensive and costly process. In the barracks just mentioned, ventilating pipes conduct outside the building all the foul gases that do not escape into the closet as a result of its greater warmth. The excreta are generally discharged into the cess-pit through untrapped hoppers, opening into a shaft which may run through many stories and is incapable of being either properly flushed or cleaned. These cess-pits are usually emptied by hand. A condition of affairs similar to the above was found by our troops to exist in many of the barracks and public buildings in the islands taken from Spain as a result of the late war. The general system of cess-pit disposal is largely used in all Latiu countries, and their military services naturally share to some extent in the prevailing customs. The Pail System. — A slight improvement over the old excavated vault is found in the paiL or tub system, which permits the removal of the excreta more easily and frequently, and with less nuisance, than is the case where the cess-pit is used. With this system, a movable receptacle of the above character intervenes between the seat of the closet and the floor ; the latter being raised above the ground-level and made of cement or other impervious material. Wlien fuU, the tubs or pails are carried away for the disposal of their contents and are replaced by empty receptacles. While local contamination of the soil is less than occurs with the use of privy-vaults, this system is highly unsanitary. Since earth is not used in these receptacles, their condition naturally becomes very filthy, then- contents are foul-smelling, are not protected from flies, and are not rarely spilled out while being removed to the dumping-ground. This method of disposal cannot be recommended. DISPOSAL OF EXCRETA, SEWAGE AND REFUSE. 535 The Dry-Earth System. — Improving on the pail system, just men- tioned, Moule showed that a slight covering of dry earth, of suitable qual- ity and character, destroyed the offensive odor of the excreta and at the same time rapidly brought about the disintegration and disappearance of the latter. Even paper was ultimately destroyed by this means, while faecal matter could not be detected by sight or smell after a period of two or three weeks. At the end of this time, earth which had been used for this purpose possessed a perfectly normal appearance and could, if desired, be employed over and over again. The destruction of the feecal matter, under such circumstances, appears to be due to the action of the nitrifying bacteria present in vast numbers in certain soils. The dry-earth system is especially adapted to posts where either the water-supply is insufficient for general water-carriage or where a doubtful permanency prevents the installation of an expensive sewer system. It may also be employed to serve a temporary purpose while a more suitable means of disposal is being mtroduced. It is far less offensive than the ordinary pail system, and should invariably be substituted for the use of privy-vaults in the absence of water-carriage. The installation of dry- earth closets is both simple and inexpensive. Dry-earth latrines are used in the British and Austrian armies at a number of stations. The French use them in Algeria; though preferring the Goux modification for home stations. In our own army, the system is employed at a number of posts. It appears, on the whole, to render very efficient service — and where cause for complaint exists, a lack of the necessary details of administration can usually be demonstrated. It should be understood that the success of the system depends on proper scavenging arrangements and efficient sanitary supervision — and if these cannot be secured, this method of disposal will prove unsatisfactory and unsanitary. As with the pail system, the saturation of the soil with filth and the pollution of the ground-water are avoided. There is, however, a considerable liability to the dissemination of possibly infectious material through carelessness in scavenging. The great point of superiority of the system consists in the fact that, by its use, the excreta are promptly rendered inodorous and inoffensive, while the possible transmission of infection by means of flies is largely avoided. One inconvenience is found in the fact that the system does not work well unless the earth to be employed is perfectly dry. In our own service, its use is particularly satisfactory on the high plateaus of the west or in other dry regions — and for the French army, Laveran states that no such excellent results can be obtained in France as are given by the system in Algeria. Another disadvantage consists in the necessity of collecting, dry- ing and storing the earth ; the supply of which to large posts, particularly during long periods of rainy weather, is a matter of considerable difficulty from the amount requhed. In dry western climates, the earth required can usually be dried sufficiently in the sun ; but in damp localities some artificial means of drying may be necessary, as by the use of improvised kihis. Earth dried in the sun appears to be more efficient in its action; when dried artificially, it is desirable that the temperature be not raised sufficiently to sterilise it and thus destroy the micro-organisms upon which its efficiency chiefly depends. 536 THEORY AND PRACTICE OE MILITARY HYGIENE. Not only should the earth be dry originally, but it must be kept in this condition, which usually implies the erection of a suitable shelter under which it may be stored. The earth should not be lumpy but should be in fine particles, to secure which quality it is best sifted and screened. There is much choice in the character of the earth to be used ; the best are loamy surface-soils, vegetable moulds, dry clay or brick-earth. Chalk, gravel or sand give only inferior results. Sifted coal-ashes may be used for this pui-pose, but while they are an efficient desiccant their deodorizing powers are very slight. Sawdust has been tried at Fort Missoula with satisfactory results, as a substitute for dry earth. Charcoal is an excellent deodorizer and is used abroad in earth-closets for this purpose ; it is not required in the military service, where careful sanitary supervision and the generous use of dry earth of good character should satisfactorily answer aU purposes. In the British army, the amount of dry earth to be provided is based on the estimate of one cubic foot per month for each soldier. This allow- ance is insufficient and does not permit that free use of earth upon which the special value of this system depends ; to obtaiu the best results, twice the above quantity will be required. The amount of earth necessary for covering each dejection obviously varies with the amount of the latter. Usually the quantity of earth should be about five times the combined weight of the solid and liquid excreta. Thus with four ounces of faeces and seven fluid ounces of urine the amount of earth required would be about four pounds. Vallin states that where clay soQ is used, about twenty per cent, more earth is required to obtaiu the same results than where garden loam is employed. For the proper operation of the dry-earth system, the earth must be systematically used and the dejecta promptly covered after their deposition. Where a number of fsecal dejections are passed without being covered in- dividually, the mass disintegrates slowly and gives off odors. In military latriues, the dry earth is usually kept in boxes on the floor of the various compartments, a scoop being provided by which the earth can be distrib- uted as required. As might be expected, however, soldiers are prone to neglect its use, and it will not rarely be found necessary to issue special orders on this subject and hold company commanders strictly responsible for the condition of the latriaes of their respective organizations. The plan sometimes practiced of having the room-orderlies look after the spriukliag of the latrine receptacles is unwise ; since this can be done by them only at infrequent tatervals, between which the system becomes offen- sive and unsatisfactory. In some foreign services, a simple an-angement has been tried, by which a sufficiency of earth is automatically deposited on the excreta by means of a valve, on puUing a cord. This arrangement has no advantages over the box of earth and scoop already mentioned, nor can the deposit of earth be as efficiently disposed as by the latter. Nothing but faeces and such urine as may be passed during the act of defaecatiou should find their way into the receptacles of the earth-closet system, as the absorbent capacity of the earth is limited and its dryness is essential to the success of the system. As a result of this fact, efforts have even been made to catch, separate and conduct away such urine as might be passed during defsecation; but this precaution is scarcely necessary, as DISPOSAL OF EXCRETA, SEWAGE AND EEFUSE. 537 sufficient earth can readily be provided to take up that amount of fluid. Urine passed at other times should not, however, be discharged into the dry-earth closets, but should be disposed of in some other way. Where the dry-earth system is in use, the latrine- building should preferably be constructed of brick, with concrete flooring raised well above the ground. The building should not be too close to the barracks, and should be so located as not to become in any way a possible source of con- tamination to a water-supply. Keady means of access for the scavenger should be provided at the rear, as by a hinged flap opening outward, so that the contents of the receptacles need not be removed through the build- ing itself. The floor of the latrine should slope to a certain point, so that any liquid which may be spUled over it may run down where it can read- ily be collected. The receptacles should not be too large, the capacity of each being not over eight cubic feet, so that the frequent removal of their contents may be imperative. If possible, such receptacles should be kept in duplicate, so that those removed for dumping, cleaning and deodorizing may be replaced at once by others. Some of the large troughs used in our posts are very unwieldy and cannot be dumped, requiring to have their con- tents shovelled out ; with receptacles of this character, the pollution of the ground in the vicinity of the latrine is certain to occur during scavenging. The receptacles for earth-closets should always be of impermeable and non- absorbent material and should never be of wood — although wooden boxes or drawers are generally in use where this system is in operation in our army. Such wooden boxes absorb much excretal matter, the odor of which no subsequent cleansing or amount of deodorants wiU remove. Gal- vanized-iron receptacles are very satisfactory for this purpose. If force of circumstances compels the use of wooden receptacles, their surfaces should be thoroughly tarred and the operation afterward repeated at intervals Of two months. Whatever the material and form of the receptacles, they should fit sufficiently closely to prevent luine and faecal matter from getting into the slide space. The latter should be ventilated by a shaft, as already suggested in the case of privy-vaults. To increase its aspiratory effect in winter and carry off any odors, the stove-pipe should pass up through this shaft, which should be made large enough for the purpose. Unless some such ventilating arrangement is made, in cold climates the odors given off by the dejecta are promptly aspirated up into the heated room before any covering of earth can be applied; and where a latrine is in constant use, the air of the room is generally bad at all times as a result. If possible, the receptacles should be kept at a point above the freezing temperature. The seats should be hinged, so as to allow a more thorough cleansing of the subjacent space when required ; for the same reason, the floor of this space should be of cement and should slope slightly outward. All scavenger work in connection with the dry-earth system is prefer- ably to be performed by civilian labor and not by that of soldiers. Such work is degrading to the military man, and although often necessary in the field, in garrison is surely not in his proper line of duty. Where civil- ian scavengers are employed, careful oversight should be had over their work and methods. The majority of them slight their tasks to a greater or less' degree, and the system is proportionately unsatisfactory as a result. Thus at Fort Sam Houston, in 1898, recommendation was made for the 538 THEORY AND PRACTICE OF MILITARY HYGIENE. abolition of the dry-earth system because of carelessness and inefficiency ia the carrying out of its details. Under many circumstances, also, the securing of the necessary scavenger labor at reasonable cost is a matter of difficulty and is sometimes impossible — particularly among the native white population m the west. Thus at Boise Barracks, in 1895, the dry-earth system installed several years previously had to be abandoned, and a re- turn made to the old system of privy-pits, by reason of the fact that the necessary civilian scavenger labor could not be secured for the post. The expense of caring for earth-closets is not small, and the more fre- quently the cleaning is carried out the greater the cost of operation — hence there is always an inducement to economize iu labor at the expense of health. The receptacles should be cleaned out, however, at least once every two days in warm weather — and a daily emptying is desirable. Dur- ing cold weather, less care is required and a cleansing twice weekly is usually sufficient. It is important to use an ample amount of earth in covering the dejections during cold weather, since otherwise the contents of the receptacle may be frozen to its sides and bottom and be removable only with difficulty. The collection of the excreta is best made at night between the hours of taps and reveille, when the closets are not in use and any nuisance arising from the operation is not observed. The refuse should be carted away to a distance of at least one mile for final disposal, preferably by burial. In the tropics, the natives who perform this duty require careful watching, since otherwise they are liable to deposit the con- tents of the carts on the surface of the ground instead of in trenches. The night-soil should not be buried at too great a depth, however, but should be given only a superficial covering of earth, since when buried too deeply the soil from the closets remains much longer in its original foul condition, through the small numbers of the bacteria upon which its destruction de- pends. In cold climates, the sanitary officer should ensure that sufficient dry and loose earth has been stored by the scavenger to last through the period of cold weather. The desire so commonly manifested by line officers, to have weak dis- infectants used in earth-closets in order to control any odor which may be present, is due entirely to a misconception of the processes upon which the efficiency of the dry-earth system depends. These disinfectant substances inhibit the action, if they do not destroy the vitality, of the bacterial fer- ments present in the soil ; there is therefore no disintegration, oxidation and nitrification of organic matter, and the whole process by which the excreta are destroyed is arrested. It is because of the absence or infre- quency of these nitrifying organisms in such soils as chalk or sand that they are inefficient when used in earth-closets ; hence the addition of any substances which would impau- the activity of such bacteria as may be present should obviously be avoided. There is no reason to suppose, in view of the well-known viability of typhoid bacilli in contaminated soil, that dry earth renders innocuous the infectious material contained in the dejecta. Hence this system offers cer- tain facilities for the spread of infectious disease not found in the disposal of excreta by water-carriage. Thus Moore showed that, in 1894, in an epidemic at Leicester, the typhoid cases were piuch more numerous in those districts where the fiecal matters were collected in tubs ; an epidemic DISPOSAL OF EXCEETA, SEWAGE AND EEFUSE. 539 FiQ. 257.— Goux Receptacle, with Absorbent Lining. in one street showing proportionately five times as many infected houses among those using the tub system as among those provided with water- closets and sewers. At Newcastle-ou-Tyne, the typhoid cases were twice as numerous in those houses provided with the dry-earth system as among those provided with water-closets. He also found that at Birmiagham, in the same year, the typhoid incidence was one and one-half times greater in houses using pails, as compared with those possessing water-closets; with re- gard to second cases of typhoid fever in fami- lies, one occurred in every fourteen houses using pails and one in every twenty-two houses using water-closets. The Goux System. — This is a refinement of the ordinary dry-earth system, as just de- scribed. In it, the pail or tub is lined with some absorbent material, such as peat or a mixture of tan, sawdust and soot. The material is pressed firmly against the sides of the container by means of a mould ; the latter being afterward withdrawn, leaving a lined cavity for the reception of the excreta. Nothing but fteces and such urine as may be passed during the act of defsecation is to be deposited in these tubs. When full, any project- ing filling is shaken down from the sides so as to cover the excreta prior to its removal. No fluid appears in the receptacle and no offensive odor is disengaged. Like the dry-earth system, the Goux system has the great advantage of being readily put into operation, and when properly managed it gives excellent results. This system is used in both the French and German armies at stations which possess no sewerage. In the German army, powdered peat is used as the lining material; but in the French service, charcoal, ashes or any drying sub- stance is employed. SEWERAGE. The removal of excreta by water-carriage is the cleanest, readiest, quickest and, in many ways, the least expensive method for its disposal. A piped water-supply, necessary for other purposes, furnishes at once a motive power at the cheapest rate ; and where channels are necessary for the conveyance away of the waste or dii-ty water used for domestic purposes in a post, they can usually be employed for the removal of excreta also with but little alteration. It would obviously be a waste of economy to allow this foul water to pass off without applying the force which is pres- ent in it to other purposes. A water-carriage system, once established, thus costs little or nothing for its operation; the latter being automatic and without dependence upon individual effort. The conveniences are much greater with such a system of disposal, and the encouragement thus given to a more liberal use of water conduces to both health and cleanliness on the part of troops. Since by the use of water-carriage all liquid or excretal waste leaves the military community a short time after it becomes refuse, it is evident that this system is far superior to privy-vaults and earth-closets for the FIG. 258.— Mould Used in Lining Goux Receptacle. 540 THEOEY AND PRACTICE OF MILITARY HYGIENE. disposal of excreta, and at many posts, within the past decade, sewerage systems have been installed to take the place of the less sanitary methods of disposal which had previously been in use. At other garrisons, how- ever, this improvement has not been made; either because of the uncer- tainty of continuance of the post as a station for troops or because of an insufficient water-supply which would render adequate flushiug imprac- ticable. At some few posts, also, the problem of sewerage and water- supply has been complicated by a winter temperature not rarely reaching forty-five or fifty degrees below zero — a. degree of cold at which no water- carriage system of disposal could be expected to remain free from the dan- ger of freezing and breakage, under the conditions usually foimd in the military service, without a disproportionately high financial outlay. It is important to remember with reference to sewerage that no im- provised arrangement, inferior apparatus or poor workmanship should be countenanced. Unless everything connected with the system is of the best quality and eminently adapted to the purpose for which it is intended, the results will be uniformly unsatisfactory. Makeshift appliances are to be avoided, since as compared with a poor sewerage system, the dry-earth closet is a sanitary improvement. Thus at Fort Sill the drainage system, originally poor, was soon reported as being beyond repair, whQe complaints with reference to the stench and frequent overflow were common. In general, to make a success of any system of sewerage, it is essential that there be a good supply of water, well-constructed and ventilated chan- nels, a proper outfall and a suitable and inoffensive means of disposiag of the sewage. If these requirements cannot be united, the sewerage system will constantly cause annoyance and may become a source of considerable danger. The main objection to sewerage systems is that they create un- derground channels connecting houses, which permit the transference of effluvia from place to place. This objection, however, is against an error of construction and not against the plan as properly carried out. A prac- tical fault in the system is that the pipes may break and their contents contaminate the soil, and this is a great evil which it requires much care to avoid. Although in discussing the question of drainage and sewerage it is necessary at times to touch within the province of the sanitary engineer, the minutiae of engineering cannot of course be considered in this volume. Sanitary Value of Sewers. — There is no more important subject than that of drainage and sewerage, so far as regards the local propagation of disease, and its details are worthy of the most careful attention on the part of sanitary officers. It may be accepted that, whatever be the defects of sewers, they are much more than counterbalanced by their advantages. Waring says, with reference to this subject : " Defective though they often are, whether in the house or in the street, they have probably been, next after the introduction of a pure water-supply, the most important factor in the reduction of the death rate." The difficulty of proving this proposition statistically consists in the number of other conditions at the same time affecting the health of soldiers, outside those of sewerage; from civil life, however, illustrations with respect to this point can be fovmd in the vital statistics of municipalities for periods before and after sewerage systems were introduced. Thus Oldright gives the following comparison of death DISPOSAL OF EXCRETA, SEWAGE AND REFUSE. 541 rates, before and after the introduction of marked sanitary improvements of this character, in various English towns. Banburv . . . Cardiff'.... Croyden . . . Dover Ely Leicester . . . Macclesfield Merthyr . . . Newport . . . Rugby Salisbury . , Warwick . . . Average mortality per 1,000, before constructiOD of sanitary works. 23.4 33.3 33.7 22.6 23.9 26.4 29.8 33.3 31.8 19.1 27.5 23.7 Average mortality per 1,000, after construction of sanitary works. 20.5 32.6 18.6 20.9 20.5 25.3 23.7 26.2 21.6 18.6 21.9 21 Saving of life, per cent. 12.5 33 33 7 14 4.5 20 18 32 3.5 20 7.5 Reduction in mortality from typhoid fever, per cent. 48 40 63 36 56 48 48 60 36 10 75 19 Simon found that after the iatroduction of sanitary improvements, con- sisting chiefly of the installation of sewerage and a better water-supply, the death rate from disease was decreased in nineteen out of the twenty-five English towns studied by him — the average reduction of mortality in these nineteen municipalities being 10.5 per cent. With respect to typhoid fever, there was a reduction in twenty-one towns out of twenty-four ; the average reduction in deaths from this cause being 45.4 per cent. In niae of these towns the reduction amounted to over 50 per cent., and in one town to over 75 per cent. Oldright gives the following figures as illustrating the corresponding decrease in typhoid fever which resulted from the gradual establishment of sanitary improvements in several German cities : Death Death rate rate per 1,000 from typhoid fever. City. Period. Sanitary condition. per 1,000 from ty- phoid fever. Period. Changes in sanitary condition. Frankfort - on- 1854-59 No sewers. .87 1875-80 Sewerage com- .34 the-MaiD. pleted. Dantzic 1865-69 No sewers, no proper 1.08 1871-75 Water-supply in- troduced. .90 water sup- ply- No regula- 1878-80 Sewerage added. .18 Munich 1854-59 3.42 1860-65 Sides and bottoms 1.68 tions for of cesspools ce- keeping soil mented. clean. 1866-73 1876-80 1881-84 Partial sewerage. Sewerage im- proved. Sewerage still fur- ther improved. 1.33 .87 .17 The decreased liability to the contraction of typhoid fever where there is a general sewerage system, as compared with dry-earth closets, has already been noted. 542 THEORY AND PRACTICE OF MILITARY HYGIENE. Sewerage Systems. — Sewers may carry off storm water, excreta and liquid waste ; liquid waste and excreta ; or finally, liquid waste alone. The first or so-called combined system is generally used in our posts ; the heavy raias occurring from time to time being of much advantage in flushing out and scouring the sewer channels. The separate system, carrying only liquid waste and excreta, costs less for construction, need be of no great size and hence can be more thoroughly flushed and is more liable to run full. The pipes may be closely proportioned in size to the daily flow of sewage, which can be calculated with some degree of accuracy from the amount of the water-supply. Separate sewers have no special advantage for military posts except in the tropics, where the long dry season and subsequent period of torrential rains would render a combined system, operating satisfactorily under all conditions, unduly expensive in both con- struction and operation. In the third class are included those sewers which merely remove waste-water from habitations; the solid excreta being disposed by the dry-earth system, as at Forts SiU, Bayard and other posts. The sewage removed from barracks, however, is a very complex liquid where all liquid wastes are removed by the same water-carriage sys- tem. The kitchen-waters contain vegetable and animal refuse, and those from baths and lavatories carry soap and detritus from the surface of the body and resulting from the washing of clothing. To f these is generally added more or less urine, and in a few instances a small number of water-closets may discharge into the sewerage system. Clearly the sewage from liquid waste alone may be so impure that there is no sanitary advantage in providing for the disposal of the excreta, either solid or liquid, by any separate system. Construction of Sewers. — In the separate sewerage ^'^sh?edsewer'^ System, where the amount of sewage is fairly constant, the pipes are small and frequently run nearly full, a cir- cular form of pipe gives satisfactory results. If storm-waters are also ad- mitted to the sewerage system, however, conduits of this shape carry their contents slowly and with only feeble force except at such times as storm waters are passing ; fsecal and other solid matters accumulate along the side and flushing is difficult. Under such conditions, where a variable flow must be provided for, the best form of sewer is that which is ovate in transverse section ; since this shape, with the small end down, affords suffi- cient space for a temporarily increased outflow and presents the advantage of a deep narrow stream, by which the deposition of sewage is prevented and the maximum scouring effect is secured with the least quantity of water. Engineers advise that all sewers over eighteen inches in diameter be built in this form. It appears to be accepted that the best shape for sewers of this general type is where the horizontal diameter is two-thirds of the vertical height, the radius describing the invert being one-fourth the horizontal diameter. The semicircle drawn upon the horizontal dia- meter becomes the upper part of the sewer, while the segment drawn on the radius becomes the invert. It sometimes happens that, impressed with the desirability of removing sewage from habitations, post authorities have used wooden drains, in the absence of more desirable material, as a means for its discharge. It is DISPOSAL OF EXCRETA, SEWAGE AND REFUSE. 543 FIG. 260. — Box Drain, Placed Angle Down so as to Avoid Deposit. only a short time before such, conduits become leaky, clogged and saturated by their contents and thus become long permanent cesspools. Such improvised arrangements are to be condemned. If higher authority per- mits their use ia spite of protest, as has been done, at least they should not be laid flat, as is usually the case, but should be set at an angle so as to give the fluid its greatest possible depth and force and thus prevent deposit. As to material, large sewers are' generally made of brick, set in cement and given a smooth inside coating of the same material. In the construction of brick sewers, they must be strongly put together and set on a firm bed, as otherwise they are Jiable to settle and develop inequali- ties in their level. Sewers less than eighteen to twenty- four inches in diameter are generally made of well-glazed vitrified earthen- ware pipe. The strength of these is usually tested by placing heavy weights on them or by dropping weights upon them when in the trench. The best test, however, is that of hydraulic pressure from the inside, for pipes which have fire-cracks and outwardly appear to be of poor quality will often stand this natural test more satisfactorily than those of better general appearance. Iron pipes must be used when any imusual strain or pressure has to be borne, as where the sewage is carried across a ravine. The pipe most commonly used is the cylinder having a socket at one end into which the next pipe fits to form a joint. The space between the spigot and the socket is generally filled with cement to make the joint water-tight, but care must be taken that this material does not penetrate to the interior of the pipe and afterward serve as an obstruction to the flow of sewage. To prevent the cement from passing through the joint, tarred gaskets are generally used ; a luting of clay is sometimes employed for the same purpose, but this is less satisfactory as it is washed out of the joints in a short time. After cementing, each joint should be carefully examined on the inside, and any cement which may have been pushed into the in- terior should be removed before the next section of pipe is laid. Joints made in this manner .are water-tight and excellently resist the disruptive encroachments of the roots of trees; once set, however, pipes thus laid are very solid and cannot be opened for examination, in case of stoppage, ex- cept by breaking one of the sections. Sewers should of course be water-tight, and a cemented joint has much to commend it on this account. Laveran states that in certain French garrison towns, where the subsoil has been contaminated by leakage from sewers, the subsequent opening up of trenches in such polluted ground has been invariably followed by outbreaks of typhoid fever. Want of attention to the foundation of sewers, especially where earthen- FiG. 261.— Common Modlflcations of Sewer Pipe. A, T-plpe, for use In ventilating and for in- spection openings ; B, T-plpe : C, V-pipe, for Junction where the main drain runs in a di- rection different from either branch ; D, bend or elbow.; E, diminishing pipe ; P, increas- ing pipe ; JT, an offset, for accomplishing a slight deflection in direction. 544 THEORY AND PRACTICE OF MILITARY HYGIENE. ware piping is used, is one of the most eommon causes of deposit and of sewage pollution of the soU. The foundation upon which the sewer rests should be firm and solid ; if pipes are used, small excavations should be made to receive the shoulders, so that these should not be called upon to bear the entire weight of pipe, contents and overlying earth, with no sup- port beneath the body of the pipe to prevent it from cracking or breaking. Provision must also sometimes be made for carrying off the ground-water by the use of loosely jointed drains or a combination sewer-pipe in which a flat, hollow bottom forms a porous subsoil drain. Where the ground water is very high, as at Jackson Barracks, it is often impossible to con- struct underground sewers and cemented open drains may be used under such conditions. The direction of a sewer should be as straight as possible in order to maintain the maximum velocity of flow ; if it requires to be changed, the curves should be gradual — the radius of the curve being not less than ten times the cross-sectional diameter of the sewer. Where sewer pipes are so laid that the alignment is imperfect in both the horizontal and vertical planes, the depressions will serve for the accumulation of matters which generate foul gases. In some instances, the in- equalities of level may be sufficient to form run- ning-traps and thus divide the sewer into dead sections ; but with any inequality of level in the floor of the sewer the movement- of its contents is materially hindered. Thus the sewerage sys- tem at Fort Huachuca, in 1896, had to be opened up for this reason. Junctions of sewers should FIG. 262.-improper and Proper ^^ made at acute and not at right angles, as the Angles of Junction In Sewer or interruption of the stream and the eddies thus formed will cause a deposit which, once com- menced, rapidly increases in bulk. Sewers of unequal sectional diameter should not join with level inverts, but the lesser or tributary sewer should have a fall into the main sewer at least equal to the difference in the sectional diameter. If a manhole is used for the junction, the bottom can always be so constructed as to give the required flow in the direction of the movement of the main current. As a general thing, when a smaU. sewer pipe has to be received in a larger one, an " increasing " pipe is used to prevent a bad joint. After the sewer has been laid and before the trench has been filled in, the pipe should be tested for strength and tightness by temporarily fixing a bend and two lengths of pipe so as to give four or five feet of water pressure. Any leaky joints which may be found can be made tight by embedding them in concrete or cement. The water should not be dis- charged from the pipes until the fiUing-up of the trench has been com- pleted, since any cracking or breakage resulting from the operation of fill- ing will thus be shown by subsidence in the water-level. A good sewer, properly laid, is indestructible except by violence ; while a poor line, poorly constructed, is a never-ending source of trouble, ex- pense and danger. Large sewer systems cannot be properly laid by un- skilled workmen and inexpert overseers. Size of Sewers. — The probable amount of sewage requiring removal DISPOSAL OF EXCRETA, SEWAGE AND HEEUSE. 545 should be estimated in advance, and the size of the sewer proportioned accordingly. If the conduit be too smaU, there will be flooding of the connections with the lower portion of the sewer, or system of sewers, with every sudden influx of storm water ; if sewers are too large, there is need- less expense of construction, sluggish flow and opportunity for the develop- ment of putrefactive processes in their contents. In general, sewers hav- ing a diameter of less than nine inches are liable to obstruction and cannot • be recommended ; the usual temptation in regard to sewers, however, is to have them too large, when the rapidity of the flow of the sewage is dimin- ished and waste lodges instead of being carried off. In estimating the probable amoimt of sewage requiring disposal, the water-supply of a garrison may be considered as furnishing an amount of sewage of equal quantity. In opposition to the condition in a growing town, in a military post — the maximum strength of the garrison of which is known in advance — no allowance need be made for possible future growth in establishing the sewerage system. Where both the sewage and rainfall are carried off by a common conduit, the amount and character of the rains must be considered — violent storms taxing the sewers more than fre- quent gentle showers. The space occupied by the military population, because of the area from which storm-waters must be discharged, is of the much importance, and with a scattered population the difficulties of sewer- age are much increased ; the configuration of the surface and character of the soil also have much to do with the size of sewers, since a considerable portion o,f the rainfall sinks in a flat, sandy surface. The configuration may likewise cause engineering difficulties, while the existence of rock or sand may also prove to be an obstacle in respect to construction or perma- nence. It is evident that, with respect to the size of sewers, the question is so complicated where rain-water is disposed of by the same system that it is impossible to lay down any fixed rules, applicable to all conditions, with respect to the size of the main channel. The matter must be ap- proached differently in each individual case, and with a full consideration of all the factors concerned. Having ascertained the maximum amount of sewage to be provided for, the size of the conduit and rate of flow can readily be determined. Velocity of Flow in Sewers. — The force which removes sewage is gravitation, and this is enabled to exert its power by reason of the liquid condition of the sewage — for the solid constituents of the latter are rela- tively insignificant. The velocity of the stream in sewers is dependent not only upon their slope or fall but upon their shape, interior smoothness and even gradient, together with the volume and equability of the flow. The velocity also varies to some extent with the nature of the material to be carried and the facilities for flushing. The minimum velocity in sewers is at the bottom of the stream; it is upon this velocity that the scouring of the channel depends. Baldwin -Lath am advises that sewers twelve to twenty-four inches in diameter should have a gradient sufficient to produce a velocity of not less than two and one-half feet per second. Eankin states that the velocii^ of flow in any sewer should not exceed four and one-half feet per second, and Eawlinson regards four feet per second as the greatest allowable velocity. A rate of six feet per second would be de- structive to sewers; and probably the best rate of speed for conduits of 35 546 THEORY AND PEACTICE OF MILITARY HYGIENE. ordinary size is slightly more than half that figure. The question of allowing proper grade is of much importance; thus at Fort Einggold an insufficient allowance in the original planning of the fall of the sewer has resulted in its repeated clogging. As showing the scouring force possessed by various bottom- velocities in preventing the clogging of sewers, Beardmore states that the following rates of movement have the effect stated on the different materials particularized : 30 feet per minute will not disturb clay with sand and stones; 40 will move along coarse sand; 60 will move fine gravel, size of peas; 120 wiU move roimded pebbles one inch in diameter; 180 wiU move angular stones one and one-third inches in diameter. Gradient of Sewers.— Sewers must be laid at . a proper inclination, since otherwise obstruction wUl occur on the one hand, or a too great velocity of discharge will test the integrity of the sewer-pipe system on the other. For efficient action, small sewers require a greater inclination than large ones. To prevent deposit in sewers from six to nine inches in diam- eter, a velocity of not less than three feet per second should be secured ; for sewers of twelve to twenty-four inches in diameter the velocity should not be less than two and one-half feet per second, and for larger sewers two feet per second. These velocities would require a fall of 1 in 140 to 1 in 200 for pipes sis to nine inches in diameter; of 1 in 400 to 1 in 800 for pipes of twelve to twenty-four inches in diameter, and for larger sewers of 1 in 244 to 1 in 784, according to size. The fall should be equable, without sudden changes of level. To show the inclination required to produce different velocities of flow in pipes of various calibers, Baldwin-Latham gives the foUowing figures : Rate op Inclination for Velocity pee Second. Two feet. Three feet. Four feet. Five feet. Six feet. 4 1 in 194 1 " 293 1 " 389 1 " 437 1 " 486 1 " 583 lin 93 1 " 137 1 " 183 1 " 306 1 " 229 1 " 275 lin 53 1 " 80 1 " 106 1 " 119 1 " 133 1 " 159 lin 34 1 " 51 1 " 69 1 " 77 1 " 86 1 " 103 lin 34 6 1 " 86 8 1 " 48 9 1 " 54 10 1 " 60 12 1 " 72 For circular pipes, the following may be considered as the maximum allowable falls: Four-inch pipes, 1 in 36; six-inch pipe, 1 in 60; nine- inch pipe, 1 in 90. These estimates are based on the assumption that the pipes are running full or half -full. Where sewage has to be carried down from a considerable height, the great difference in level constitutes no practical difficulty ; since the inter- nal pressure can be prevented from becoming excessive by the establish- ment of disconnecting manholes at frequent intervals. Discharge from Sewers. — To calculate the discharge from sewers, Notter and Firth recommend the following formula : V = 55x(VlJx2P) In this, V = velocity in feet per minute ; D = hydraulic mean depth in feet ; F = fall in feet per mile. Then if A = section-area of current of fluid, DISPOSAL OF EXCRETA, SEWAGE AND REFUSE. 547 V A = discharge in cubic feet per minute. To use this formula, the hydraulic mean depth when the sewage is flowiag, and the amoimt of fall in feet per mUe, must be ascertained. The hydraulic mean depth is the section-area of the current of fluid divided by the wetted perimeter. In circular pipes it is always one-fourth the diameter ; whether running fuU, half-full or otherwise. In egg-ghaped sewers, the hydraulic mean depth varies with the amount of water flowing through them, but in sewers con- structed on the usual plan, where the transverse diameter is two-thirds of the vertical, the hydraulic mean depth is as follows : Running fuU, trans- verse diameter X .2897; two-thirds full, transverse diameter X .3157; one-third full, transverse diameter X .2066. The wetted perimeter is that part of the circumference of the pipe wetted by the fluid. In an egg-shaped sewer, under these three conditions, it equals the transverse diameter multiplied by 3.9649, 2.3941 and 1.3747 respectively. The fall in feet per mQe is easily obtained, as the fall in one hundred or two hundred feet can easily be measured and the fall per mile calculated from this by dividing 5,280 by the denominator of the fraction. Bailey-Denton has calculated the discharge from different sized pipes, running full at different velocities, as follows : Diameter of pipe In Inches. Velocity three feet per second. Delivery in gallons per minute. Velocity four and one-half feet per second. Delivery in gallons per minute. Velocity six feet per second. Delivery in gallons per minute. 3 4 6 9 54 96 316 495 81 144 334 743.5 108. 193 432 990 Sewer-air. — ^The rise and fall of sewage, with alternate wetting and drying of the walls of the conduit, favor putrefaction of organic deposits with the formation of gases — of the absence of which the fact that no foul odor is apparent is no proof. Contrary to the opinion long entertained, sewer-air does not appear to be particularly hurtful to the organism, save in so far as it may favor the occurrence of disease through depression of the powers of vital resistance. A few instances of acute mephitic poisoning of an intense degree have been recorded ; but usually the early symptoms resulting from the breathing of sewer-air are not especially marked. When the air of sewers penetrates into houses, and especially into bed-rooms, it may ultimately cause a greatly impaired state of health, especially in children. The latter lose appetite, become pale and languid, and suffer from diarrhoea ; older persons suffer from headaches, malaise and feverishness ; there is often some 'degree of ansemia and it is clear that the process of aeration of the blood is not per- fectly carried on. In some cases, decided febrile attacks lasting three or four days, attended with great headache and anorexia, have been known. Houses into which there has been a continued escape of sewer-gas have been so notoriously unhealthy that no persons would live in them, and this has been not only from the prevalence of fever, but from other diseases also. Rawlinson mentions the fact that when the wind blew into the open mouths of the sewers of the military hospitals at Scutari, during the Cri- mean War, there was an accession of fever cases among the sick, and those 548 THEOEY AND PRACTICE OF MILITARY HYGIENE. already existing took on a more aggravated type. There appears to be some relation between defective plumbing and outbreaks of typhoid fever and diphtheria, particularly the latter, but no direct proof of such a causal relation has as yet been adduced. It may be that the sewer-gases, by giv- ing rise to a relaxed and unhealthy condition of the mucous membrane of the throat, may increase the liability to attack by diphtheria ia the event of subsequent exposure to a specific infection. In connection with the possible relation of sewer-air to specific dis- eases, some interesting experiments by Alessi are of value. This investi- gator noted the effect of the inhalation of sewer-air and the gases from putrefying materials upon animals — ^rats, rabbits and guinea-pigs being selected. After exposure to sewer-air, which was accomplished by placing the animals in a box with a perforated bottom communicating directly with a drain, each was inoculated with a small quantity of only a slightly virulent cultivation of the typhoid-fever bacillus ; while other animals were similarly treated, except that they were not compelled to inhale sewer-air but were kept in their ordinary surroundings. Infected rats, after breath- ing this more or less foul air, began to lose theii vivacity and after a time grew thin, although they ate voraciously; out of forty -nine which were inoculated with the enteric-fever bacillus, thirty-seven died, exhibiting the typical symptoms of enteric-fever infection. Of the forty-one rats, however, which although infected with enteric fever had not breathed sewer-air, only three succumbed. Thus the inspiration of drain-air had so far predisposed these animals to infection from enteric fever that a small dose of an al- most harmless growth of this organism proved fatal to them. Guinea-pigs and rabbits, exposed in like manner to gases from materials in a condition of active decomposition, also acquired a predisposition to typhoid infection ; for out of seventy-two guinea-pigs inoculated, fifty-seven died, while not one of those treated with the infective agent of enteric fever, under ordinary surroundings, succumbed. Similarly every one of eleven rabbits, treated and exposed to sewer-air, died, while not one of the inoculated animals lost its life when kept in fresh air. Alessi also found that the inhalation of gases from putrid substances enabled a small dose of a weakened culture of the bacillus coli communis, normally present in the intestine, to produce fatal results when purposely introduced into the animals thus exposed. He also ascertained that it was during the first two weeks of exposure to nox- ious gases that the animals were most easQy predisposed to enteric -fever infection, for no less than ninety per cent, of all the animals inoculated during the first fortnight died, while seventy-six per cent, succumbed of those inoculated in the third week. This fact, Alessi states, may partly explain how it is that some people who habitually breathe contaminated air do not appear to suffer any evil results, having in course of time gradu- ally become accustomed to it, while strangers exposed to the same condi- tions, without previous experience, may suffer very severely. The air in sewers is in a constant state of movement from several causes. The movement of the sewage may cause a flow of air in the direction of its course, while, on the other hand, a strong wind blowing against the open mouth of a sewer may drive the contained aii* back with considerable force. Temperature is also an important factor in influencing the move- ment of air in sewers — its activity increasing with the difference in temper- DISPOSAL OF EXCEETA, SEWAGE AND EEFUSE. 549 ature between the sewer-air and that outside. If at any time there is a rapid flow of water into a sewer, as in heavy raias, a bulk of air equal to that of the entering water must be displaced, this often occurring with great force. Out of which end of the drain the air passes, supposing the former to be unventilated, depends on force of circmnstances. It moves readily in the line of least resistance, preferably in an upward direction as a result of the greater gravity of water. Under such circumstances, it is possible that the air-pressure in poorly constructed sewers might be sufficient to force a weak water-seal; ordinarily, however, sewers have numerous openings for communication with the outer air, and the internal pressure in sewers is thus rarely different from that of the external atmosphere. The air in house-drains is often even more impure than that of the main sewers. This is the case also in other parts of the drainage system, and is to be accounted for by the numerous openings in the sewers, by the porosity of their walls, and by the amount of water in sewers being often so great and its flow so rapid as materially to lessen the deposit of sewage and the resulting generation of gases. Ventilation and Disconnection of Sewers. — To avoid the dangers attendant upon the presence of a considerable proportion of sewer-gas in closed conduits, measures are taken to ensure its escape into the outer air and equalize the pressure within and without the pipes. This is com- monly done by the use of man-holes or ventilating shafts, usually the former. These are put in at frequent intervals, particularly at points where tributary sewers join or where a sewer deviates from a straight course. Eawlinson considers that each main sewer should have an open- ing every hundred yards ; but for ordinary post-sewers, the space between ventilating openings may be often several times this distance. Man-holes are generally built of bricks, set in in cement ; the drain being continued along the floor by half-channel pipes laid in the same substance. The cemented surface is raised several inches above the pipe, so as to prevent the sewage from overflowing. Ordinarily, gratings are used to protect man-holes; terminal man-holes particularly requiring an abun- dance of air. The use of pits at the bottom of man-holes, sometimes ad- vised, is not to be recommended; since it favors the deposit of material which undergoes putrefaction and gives off offensive odors unless it is con- stantly being removed. A sewer is disconnected when there is a large vent at the point of con- nection with a drain, either protected or not by a running-trap and water- seal. By this means the free ingress of fresh air or the exit of foul air, as the pressure may determine, is secured. In practice, this is not easy to carry out in snowy or very cold climates. Care of Sewers. — The choking of sewers by deposits is brought about by any of the causes favoring sedimentation, such as original bad construction, too little fall, sharp cm-ves, sinking of the floor, want of water or check of flow by tides. Such deposits may occur to some extent in well-made sewers. Even in thos^ of so-called self-cleaning character, the changing level leaves a deposit on the walls, which, being alternately wet and dry, soon putrefies. In foul channels, a quantity of slimy matter often collects on the crown of the sewers, sometimes several inches in thickness and generally very offensive in character. Where rain-water en- 550 THEORY AND PRACTICE OF MILITARY HYGIENE. ters sewers it washes them thoroughly at times, but it also carries ia a con- siderable amount of debris and gravel. If artificial flushing is required, this is usually accomplished in the military service by playing the fire-hose into it — an iaefficient method — or by suddenly discharging the contents of a water-cart into the sewer. Where the quantity of water normally passing through the sewers is insufficient, it is sometimes advisable to hold the sewage back by gates until a sufficient quantity has collected to wash the entire channel by its sudden discharge ; or tip-tanks are used for flush- ing, which discharge themselves when full. These arrangements are particularly necessary where a sufficient fall, to ensure a good flow, cannot be obtained in the sewer. Regular flushing is very important in keeping sewers clean, and where deposits cannot collect no foul gases are generated. Engineers are by no means agreed as to the quantity of water required for preventing deposits in sewers intended for the removal of excreta. Brunei regards twenty-five gallons per head per diem as the amount required to keep sewers clear, and with this he believes that there should be an occa- sional allowance for flushing; but in some cases a well-laid sewer and good fall require less, and in other cases bad gradients or curves require more. Cleaning of sewers by other means than flushing has sometimes to be resorted to, notwithstanding the fact that theoretically they should be so constructed as to be self-cleansing. To facilitate this operation, man-holes, inspection-openings and cleansing-openings are provided. Deposits at such points can be removed directly, while the cleansing of the channel between these openings is accomplished by the use of brushes, wheels and scrapers on long jointed rods ; or attached to a rope which has been carried through between two man-holes by means of a floating metal globe four inches smaller than the diameter of the circular sewer. The pressure of the flow- ing sewage under and around this globe, as it is carried through by the current, does much to scour out the channel and remove the softer deposits, while any firmer material is subsequently broken down by the scraper. Local obstructions not rarely occur in the more poorly constructed sew- er systems of our posts, as at Forts Ringgold and Huachuca, requiring forcible intermittent flushing or even frequent opening of the sewers to prevent clogging and remove obstructions. In several instances, as at Fort Baker, the roots of trees have forced their way through the joints of badly laid sewers, with resulting leakage and clogging. The inspection of sewers is usually a matter of great difficulty, on ac- count of the means of direct access being insufficient and the length of the sewers being great. A foul and clogged condition is commonly recognized by the presence of offensive odors and the damming back of the sewage into the afferent drains. BRAINAaE AND PLUMBING. Drains. — By the term drain is meant that conduit which intervenes between the waste and soil-pipes and the sewer, and which carries away the sewage of a single habitation. Lilce sewers, drains should be so con- structed that there is no leakage, and should be air-tight save at points where ventilation is specially provided. Ventilation should be as free as DISPOSAL OF EXCRETA, SEWAGE AND "REFUSE. 551 the safety of the water-seal permits. The drain may be of tile outside the buildiQg but should preferably be of cast iron, with caullced leaden joints or wrought-iron screw joints, and should be so located as to be readily ac- cessible for inspection within the building. It is generally either hung on the cellar wall or suspended from the ceiling ; if this disposition is imprac- ticable, it may be laid in a cemented trench having a movable cover. Un- der ordinary circumstances, it should not be buried under the cellar flooring ; if this appears to be absolutely necessary, the whole pipe may be embedded in concrete, so that any fracture will not result in leakage, and should be provided with an access opening at each end. Where a drain passes under the wall of a building, thete should be a relieving arch or some suitable ar- rangement to prevent the pipe from being broken by settling of the foun- dation. Within the building, the drain should be provided with openings to permit of cleansing, these openings to be flush with the cellar floor and to be closed by brass sewer-plugs. Every house-drain should be trapped as near as practicable to its junction with the public sewer; an opening for ventilation being provided on the house side of the trap and the building and sewer being thus com- pletely disconnected. The drain-trap should be a running or half- S trap, kg. zes.-section of Tix-inch siphon witu and should be placed so as to be readily MmimsMng ?^p^e^ana^A^^^^^ accessible. The drain-pipe should be capable of being opened for cleansing purposes by an access-pipe beyond the water-seal. Buchan's ventilating and disconnecting trap is much used for the disconnection of drains. Some authorities, however, are opposed to the drain-trap and favor a free and unobstructed vent from the sewer to the roof, furnished by the drain and its ventilating pipe. The inclination at which house-drains are laid depends upon the veloc- ity of the current desired. This should be sufficient to secure efficient scour- ing of the channel without special flushing ; but, on the other hand, the inclination should not be so great as to allow the liquid portions to flow away, leaving the solid matters behind. While the fall to be given a drain must be decided according to the special circumstances of each case, it may be taken as a general rule that the average house-drain should have a fall in about one in fifty. Maguire gives the following rule for determining the necessary grade : Multiply the diameter of the drain in inches by ten ; thus a four-inch drain should have a fall of one in forty, a six-inch drain of one in sixty, and so on. These estimates are based on the supposition that the drain wiH run half-fuU. When running fuU, the discharge is of course doubled, but the velocity atid scouring force have no further increase. Where the current is feeble or the fall insufficient, an automatic flush-tank may be placed at the upper end of the drain. With respect to the size of the drdin, one of six inches in diameter wOl suffice for the needs of a com- pany barrack and is more readily kept free from deposit than one of larger size. In the drainage of barracks it is customary to put access-plugs at each angle of the. pipe, to facilitate the removal of clogging material. 552 THEORY AND PRACTICE OF MILITARY HYGIENE. The junction of pipes with draias, and of drains with sewers, should al- ways be made at acute angles, since otherwise stoppage is liable to result. Like sewers, drains are usually cleaned outside the building by means of man-holes, through which these wage flows in half-round pipes. Within the building, access-pipes are used for this purpose. The use of movable caps, sometimes advised, is of no advantage under such circumstances; and leakage is liable to occur after the cap has once been removed. Drain pipes should be regularly flushed, and cleaned when necessary. The latter is generally done by flexible bamboo or jointed rods, provided with screws and rollers to loosen the sediment. With straight drains, obstructions are of course more easily detected and removed. The stoppage of drains may be noted by throwing milk of lime into a sink or closet and watching for its appearance in the man-hole disconnecting the house-drain and sewer. The spouts for the conduction of rain-water from roofs should discharge in the open air over trapped gratings having a catch-box for gravel. Some- times these rain-leaders have opened directly into the drain, as at Fort Bayard, and acted as ventilators for the latter — the foul air being thus often conducted to the vicinity of windows. All waste-pipes and overflow- pipes should terminate in the open air like rain-leaders, and be thus cut off from direct communication with drains. Soil-Pipes. — ■ The soil-pipe re- ceives the discharges from water-clos- ets and conducts them to the 'drain. All things considered, wrought-iron screw-jointed pipes are probably the best for this purpose, thus avoiding any leaky jointing. Drawn-lead pipes are excellent, but are both costly and heavj- ; seamed-lead pipes should not be used. Cast-iron pipes are cheaper, but they must be strong and have their inner surface' as smooth as possible. Castings are not rarely of uneven thick- ness ; and, as with a rope, the strength of a line of piping is its weakest point. Where air-bubbles are present to weaken the material, the strength of the pipes may be tested by sharp hammering. To give a smooth inside finish and prevent rusting, iron pipes are sometimes given special treat- ment. Angus Smith's process consists in dipping the clean pipe into a bath of coal tar, pitch and linseed oil, heated to a temperature of 400° F. The Barff process consists in producing a coating of black oxide of iron by exposing the clean pipe for eight or ten hours to a temperature of 1,200° F. in an atmosphere of super-heated steam. The- use of artificially coated pipes is, however, being discontinued. All jimctions in the soil-pipe must be solidly made. Cast-iron pipes are joined by pouring molten lead into the sockets when the lengths are in position, a small packing of oakum hav- ing previously been introduced to prevent the liquid metal from penetrating to the inside of the pipe ; when cold, the lead is driven home with a caulk- ing iron. Lead is joined to iron by tipping the leaden pipe with a brass ferrule, which is afterward caulked into the iron with melted lead. Where lead pipes are made to connect with earthenware closets, the joint is usually made tight by the use of red lead. Throughout the installation Fig. 264.— Disconnecting Obamber, in Longitu- dinal Section. DISPOSAL OF EXCRETA, SEWAGE AND EEFUSE. 553 of the soil-pipe, every joint should be made with a view to its being tested under hydraulic pressure. Particularly where the whole circumference of the pipe is not easily accessible, this test will often reveal serious leakage around caulked joints. The descent of the soil-pipe should be as direct as possible, and when carried laterally the pipe should have a decided grade with but few turns. Where sucli turns are necessary, they should be as gradual as possible. The water-closet pipe should join the soiL-pipe at an acute angle, and by as short a length of pipe as possible. The outlet of the soil-pipe should be full bore and should join the main drain at an acute angle. Provision should be made so that the pipe can be opened at this point for inspection and cleaning, since it is particularly at this junction that obstruction is liable to occur. For company barracks, soil-pipe four inches in diameter is of sufficient size. The pipe itself should be carried up fuU bore above the roof, terminating away from all windows or chimneys. Sometimes an upcast ventilating cowl is placed over the open top; Waring, how- ever, prefers to use no cowl but to make the top of the soil-pipe flare slightly. In hot climates, soil-pipes should be protected against the direct rays of the sun, so as to avoid their becoming bent or their joints from opening from expansion. However carefully the soil and drain-pipe system is constructed, a cer- tain amount of sliming of its walls is unavoidable; the putrefaction of such adherent material giving rise to dangerous and offensive gases. These should be removed by ventilation, which requires two openings for its ■efficient action. The latter are secured by extending the soil-pipe through the roof, with a vent of full size communicating with it by a branch pipe outside the house. This arrangement, from the greater warmth of the house, creates a constant current of pure air through the soil-pipe. When the closet is used, the current of air is of course re- versed, as a result of the passage of the water downward through the pipe. If the water-seal of the closet should fail from any cause, by this ar- rangement fairly pure air and not sewer-gas would escape into the build- ing, and thus the danger from accidentally imsealed traps is materially lessened. Where the drain is long, it is sometimes advisable to place a disconnecting trap and water-seal close to the budding, so that the air circulating in the soil-pipe may be as free from sewer-gas as possible. By this arrangement, also, back-pressure against the water-seals of interior traps, either through the production of gases by putrefaction or by a forci- ble and sudden flushing of water, is thus prevented. Traps. — It is highly important to prevent the entrance into habita- tions of air from pipes soded with excreta or waste-water; a result stu-e to occur unless means are taken to prevent the aspiration of the foul air into the budding by reason of the greater warmth of the latter. Experience has shown that simple water-seals afford the most efficient means of ex- cluding such sewer-gas; all mechanical devices for this purpose, such as valves, balls and plungers, being vmcertain in action and hence unsatisfac- tory. To provide an efficient barrier against the passage of air, a depth of water of at least three-fourths of an inch, standing above the highest level of water in the curve of the trap, should be provided. It is true that sewer-gas dissolves in water to some extent; but as the supply in the 554 THEORY AJ^D PRACTICE OF MILITARY HYGIENE. traps is frequently renewed, this need cause no inconvenience in practice. AU fixtures should be so trapped that while exclusion of foul air is as- sured, at the same time all filth shall be immediately carried away by flushing and the trap refilled with fresh water. Every portion of a trap should be scoured out with each flush, but this thoroughness of action by no means necessarily involves any waste of water. Many traps are sO' constructed, as the mid-feather and D-traps, that no amount or velocity of water can clean them. The inner surface of water-closet traps should be perfectly smooth, with no projecting portions to retain filth — which implies their construction of earthenware or enamelled iron. The general disadvantages of traps are that they furnish a check to the flow of water through the pipes and an obstacle to the escape of solids. In special in- stances, traps are ineffective by means of bad laying, fouling from use, in- suflicient flushing and loss of the water-seal. The factors tending to destroy water-seals are : Siphonage, back -press- ure, evaporation, capDlary action, accumulation of sediment and leakage. The first three depend on the action of the surrounding atmosphere — ^the last three have relation to the character of the trap and the nature of the substances which enter into it. Siphonage results from the action of a heavy column of water falling down a soil-pipe from one fixture and thus producing a partial vacuum, as a result of which the equilibrium of the seal in another fixture is broken by atmospheric pressure within the closet. Trap-siphonage may also depend upon the rapid discharge of water through FIG. 265. — vTnted ^^ unveutcd closct-pipe, where the seal may be broken by the sheer momentum of the mass of escaprag water. Small pipes and shallow water-seals are much more liable to siphonage than are large pipes and deep seals. Where two siphons succeed each other in the same pipe, without a sufficient connection with the outer air between them, the lower siphon will suck the other dry. Back-press- ure results from the descent of a heavy column of water in a main soil- pipe to near its end, where there is an abrupt bend or some other obstacle to the escape of the air which has been compressed in front of it. The latter, moving in the direction of least resistance, may pass up a branch pipe and force the water-seal. To produce back-pressure, the descending column of water must have acquired considerable velocity and there must be an impediment to the escape of air before it. The fixture whose trap is forced will therefore be near the bottom of the soil-pipe. The pressure of sewer-gas by itself will rarely be sufficient to force a water-seal. Back- pressvire and siphonage are complementary and both cannot occur in the same fixture. Both back-pressure and siphonage may be avoided by equalising the air-pressure within and without the pipe, by venting the latter in the top of the bend by a pipe which opens into the outside air or into a general vent- pipe. The vent-pipe should have the same diameter as that of the trap-pipe, since the object of such venting may be readily defeated if the pipe be so small that the necessary amount of air cannot be admitted in a given time. Sometimes the same result is brought about by clogging of the vent-open- ing from the accumulation of waste matters washed into it during the use DISPOSAL OF EXCEETA, SEWAGE AND EEFUSE. 555 of the trap. Friction also must be considered in this connection and the vent-pipe should thus be as short and straight as possible, for the resis- tance produced by the walls of a long, narrow and perhaps tortuous chan- nel may be a greater obstruction than the inertia of a light body of water in the trap. On the other hand, too free access of air greatly increases the lia- bility to loss of the water-seal from evaporation. Where vent-pipes are used with a number of traps, they are usually made to unite in a single ventilat- ing pipe, which may end above the roof like the soil-pipe or open into the latter at a point just above the highest fixture. The seals of traps are often broken as a resiilt of evaporation; the rapidity of the process varying with the temperature and movement of air over the water surfaces. As just mentioned, the process of evaporation is greatly accelerated by the use of vent-pipes — and such a vent has been shown some- times to destroy a water-seal through evaporation in less than a week. To overcome this fault of vent- pipes and still avoid the dangers of siphonage, special devices have been put on the market. Among these, the " Sanitas trap " gives excellent results. In this apparatus, a projecting reservoir having an inside pro- tection of fine wire-gauze is screwed into the farther arm of an S-trap at about the height of the water level. As water and excreta are flushed through the trap, reverse cmrents are formed by which the side reservoir is filled with fluid while the solids are car- ried off through the escape-pipe. As soon as all the water in the trap has been discharged, the bend in the trap is refilled by the water which runs out of the reservoir as soon as the pressure is relaxed. As the reservoir of this trap ultimately collects a certain amoimt of solid material, the former, usually made of heavy glass, should be unscrewed from time to time to permit of cleansing. Traps are occasionally emptied of their water by capillary action ; which results where a rag or bit of string has one end passed up over the iva- ther bend of the trap, while the other end is im- mersed ia the liquid. The water in the trap is rapidly removed under such conditions. UnseaMng of its water-trap is sure to occiu- if a fixture remains unused for a certain length of time, this depending on the warmth of the weather or room and on the depth of the water in the trap. Hence vacant barracks and quarters should be given attention in this respect, since where the seal is broken the building is soon filled with sewer-gases. This is es- pecially important iu the case of double quarters or barracks, since neglect Fig. 266.— Method of Con- nectlng Water-closets with Soil-pipe, together with Venting of Traps. FIG. 267.- ' Sanitas" Non-Vented Trap. 556 THEOEY AND PEACTICE OF MILITARY HYGIENE. FIG. 268.—^, Running trap ; B, S- trap ; C, three-quarter S-trap ; D, half S-trap. of this kind in one set affects the sanitary condition of the adjoiniag quar- ters. Where buHduigs are to be long vacated, and periodic flushing of the traps cannot be relied upon, the water-seals can be prevented from being de- ^^ stroyed by pouring a little oil iato the fixtures. H^r^fl wm^^^i^ The back part of the seal is protected ia the ""^^r I^qP^^ same way, the oH being passed ia through a curved pipe beyond the bend ia the trap. A temporary obstruction in an ordinary siphon water-closet trap may be cleared away by making up a soft swab on the end of a stick, so that the whole shaU. have a diameter about equal to the bore of the siphon, and workiag it up and down like a piston after the trap has been filled with water. Obstructions of a fairly soft nature are thus readily expelled and forced into the soil-pipe. An ex- amiaiag eye is often put ia siphon traps to facilitate cleansiag; but when this is located over the bend, cloggiag results and the flow is retarded. Traps are made ia an almost iafiaite variety of forms, but aearly all those now employed are made by bendiag an ordiaary pipe to a greater or less extent, so that a body of water completely closes off the lumen of the pipe. Traps of this character are not only the most simple but also the most satisfactory. The common forms are the runniag trap — a shallow bend ia a nearly horizontal pipe — the S, half-S and three-fourths S. Sometimes these bends are enlarged so as to prevent siphonage, but such pot-traps collect much solid material and practically become nothing but small cess-pools. The ordiaary runniag-trap is sometimes made with two openiags beside the ialet aad outlet, by which cleansing of the further side of the trap and ventilation of the hither side may be secured. This trap usually has a flat external bottom which ensures its beiag laid level. Buchan' s trap merely has an access-pipe for cleaniag the draia beyond the water-seal. The sewage enters the trap with considerable fall, so that the latter is flushed clean. Mechanical devices have sometimes been used to iacrease the ef&ciency of a water-seal or guard agaiast its loss. Thus ia Bowers' trap a rubber ball is buoyed by the water agaiast the mouth of the pipe leading from the fixture. The discharge, ia passiag, tem- porarily displaces it ; but it immediately resumes its guard, closing the aperture so loag as sufficieat water remains to float it into position. Mechanical closures of traps, what- ever their character, are not only wholly superfluous but dangerous, since opportunity is afforded for the lodgment of filth and the proper operation of the trap, after this has occurred, cannot always be ensured. Another bad form of trap, which requires special no- tice because some of this pattern are still ia use ia our service, is the D-trap. In this apparatus there is a large surface which be- comes coated with filth and generates foul air. The trap is generally rect- angular in section, and has many sharp angles, projections and recesses by which the deposit of filth is favored. Fig. 269.— Buchan's Trap. Fig. 270.— Bowers' Trap. DISPOSAL OF EXCRETA, SEWAGE AND REFUSE. 557 Fig. 271.— D-Trap. (After Notter and Firth.) (Alter The mid-feather or dip-trap, sometimes used iu comiection with drains, is merely a box having an entry at one side and a discharge pipe at the other, with between them a partition reaching below the level of the pipes, so that its lower edge is always to some extent mider water. The trap is not self-cleansing, and heavy substances subside and collect in the box. Its disadvantages are obvious. Somewhat analogous to this trap, the flap-trap is sometimes used ; it possessing a hinged valve which allows water to pass in one direction, but which is so hung as to allow it to close by its own weight. It is intended to prevent reflux of water from sewers into the secondary drains, and is also supposed to prevent the passage of sewer-gas, for which purpose it is a very imperfect safeguard. The ordinary form of gully -trap is a very simple and efficient apparatus so far as the drainage of yard and rain-water pipes is concerned. It is in- tended to retain sand, gravel and other heavy ma- terial which may be carried in by the water and thus prevent clogging of the pipes. It is essen- tial that the catch-basin be periodically cleaned out and any deposits removed. To facLhtate this, a bucket with a lifting handle is sometimes made to fit accurately in the reservoir of the trap. Areas on which water may accumulate are often drained by the use of the beU-trap. In this apparatus, a perforated metal plate permits the water to enter a basin which lies underneath it, and when this water rises to a certain height it overflows into a central pipe which carries it into the drain. A hemispherical cup attached by its bottom to the under surface of the plate makes a loosely-fitting cover for the mouth of the pipe, and, by dipping into the water contained in the basin, pre- vents the escape of emanations from the drain. This form of trap is very defective from a sanitary standpoint and should not be used. It is unsealed whenever the bell cover is left off and the small quantity of water which forms the water-seal soon evaporates. In order to hasten the flow ,of water through the discharge pipe, the cover is frequently removed, leaving the waste pipe untrapped. The bell is also easily broken off from the perforated plate, in which case the seal is destroyed and sewer- gas escapes. Testing of Plumbing. — "Sanitary engi- neers consider that an unusual smell is" gener- ally the first evidence of something wrong, and FIG. 274.-BeUTrap. ^^^^ ^^^^ ^j^.^ -^ ^^^^^^ (-^ ^^g gQ^j.ce the evil is half cured. If the basement smells generally offensive, a leaking drain- pipe, badly jointed or broken by settlement, may be searched for, and where this has been improperly laid the leaky drain may show itself in dampness FIG. 373.— Mid-feather Trap. Notter and Firth.) Fig. 273.— Ciommon Gully Trap. (Af- ter Notter and Firth.) 558 THEORY AND PEACTICE OF MILITARY HYGIENE. of the paving or soil ia its vicinity. If rats are often seen, the drain is probably in direct communication with the sewer, and the presence and condition of traps should be ascertained. Where a smell arises from a particular sink or trap, it is evident that there is no ventilation of the drain, or at least no trap at the entrance of the drain into the sewer. Where cess-pools are in use, such odors generally mean that they are unventilated. Traps full of foul black water, impregnated with sewer-gas, often emit foul odors. These odors can generally be removed by flushing, but the character of the trap as regards its self-cleansing properties should be ascertained. Where odors are noticed on upper floors in quarters, they may be due to an imtrapped or defective closet, a leaky soil-pipe or its improper connection with the drain below. Where smells are only occasional and occur during flushing, it is probable that the odors are due to lack of trapping iu the hopper or closet-pipe. A slight escape of impure air from drains may be difficult to detect, and the odors may be attributed to deficient ventilation. Where the drain system has been treated with strong-smelling disinfec- tants, inspectors obviously cannot detect sewer odors. As already noted, smells from drains are not necessarily of a foul nature, and a close, sweet smell may often be detected." In testing pipes and traps, the cover and skirting boards should be re- moved ; all underground pipes and traps should preferably be laid bare and every joint and bend examined. If this cannot be done, the following measures may be tried : Let water run down the pipe and observe whether there is any smell. Should there be, the pipe is either full of foul air and requires ventilation or the trap is bad. If a lighted candle or piece of smouldering paper be held over the entrance of the pipe, a reflux of air may be found with or without water being poured down. It should also be noted whether the water runs away freely at once or if there is any check to its flow. From this, the clogging of the trap or pipe may be inferred. Suspected leaks are searched for by water, smoke or some pungent chemical. Of these methods, the test by water is best, since it reveals cracks which may be filled up by the thin coat of paint given the pipe on leaving the foundry. The test is very severe, but is certain in its results. It is performed by plug- ging the pipe and filling it with water until the latter reaches the level of one of the traps — any sub- ^„ sidence in the level of the water denoting a leak. Fig. 275.— Sectional View of -,,,,, , ,, . ^. . ^ ° . Drain-plug In Position. Jbor the best results m practice, a special plug is em- ployed. This consists of two galvanized-iron discs between which is a rubber ring ; on tightening these discs by means of a thumb-screw, the rubber ring is expanded against the walls of the pipe, making an air-tight joint. To remove the plug, the cap A of the hoUow bolt is removed, so that the water can escape gradually and without swamping the operator. Where there is considerable pressure, the plug should be held in place by a piece of timber, to avoid its being forced out during the operation. Difl'erent-sized plugs are of course required for pipes of different diameters. For this test, no great head of water is re- quu-ed — not more than two feet. If leaks appear at aU, they usually DISPOSAL OF EXCRETA, SEWAGE AND REFUSE. 559 occur with a few inches pressure and always under that of a few feet. If after one or two hours there is no change iq the level of the water, the pipe system concerned may be considered sound. No quartermaster should accept and pay for plumbing until the waste-pipe system has been thoroughly tested by water ; experience showing that joiats found to be originally tight rarely develop leaks subsequently. Sometimes a draia of doubtful tightness is filled with smoke by the use of a smudge-and-beUows apparatus, when the situation of a leak wOl be shown by the appearance of the smoke. Smoke-rockets have also been used for this purpose, but the smoke test, as a whole^ may be regarded as least satisfactory of the several named. A simple method for the detection of leaks consists in the use of oil of peppermint ; an ounce of this in a few gallons of hot water being poured down the pipe at its highest point. As this oil is very volatile, there is no difficulty in locating any leak by the odor. In making this test, too much care cannot be taken, and at least ten minutes should be allowed between pouring in the oil and beginning the search, so that the odor may penetrate to every part of the system of piping. In searching with pep- permint, aU ventilating openings should be temporarily stopped up, and the one who uses the oO. must remain at his post while another searches for the leaks. Sanitary inspectors now largely use glass grenades charged with oil of peppermint or other pimgent chemi- cals. One of these is sometimes wrapped in a piece of tissue paper, broken in the fingers and dropped into the trap, through which it is at once washed by a bucket of water. The paper becomes saturated and allows the . scent to circulate through the pipes. A better arrange- ment consists in placing the grenade in the receiver of the patent exploring-apparatus, as shown in Fig. 276. ma'm^ This is passed through the water-seal under the dip of the trap, when its buoyancy wiU float it to the drain side of the latter. The cord attached to the apparatus is made fast, giving two or three feet of play, and a bucket of warm water is poured suddenly into the trap, which washes the apparatus into the pipe. The line is given a slight jerk as it tightens, which breaks the grenade and allows its pungent contents to be discharged. The apparatus is allowed to remain in situ while the test is being continued, since on removal it is necessarily somewhat impregnated with the odor of the chemical employed. General Considerations. — In respect to plumbing and drainage, even more than in any other department of building, it is essential that only sound and durable materials be used. It would seem superfluous to call attention to this point, did not the too frequent presence in military posts of cheap apparatus, poor material and bad workmanship, installed under a more economical administration, show the necessity for such action. It must be repeated that in the military service no makeshift appliances as regards drainage or sewerage should be allowed. No emergency is to be met when a sewerage system is installed, and no excuse is thus furnished for the employment of improvised apparatus. In a plumbing system the essentials are : A sound water-seal, immedi- 560 THEORY AND PEACTICE OF MILITAEY HYGIENE. ate and complete removal of waste, complete ventilation, thorough and fre- quent flushing, soundness and durability, tightness as regards air and water, economy of construction and operation, automatic and noiseless operation. In general, the amount of plumbing should be reduced to the lowest pos- sible limit ; while the cardinal point of simplicity is always to be kept in mind. The entire arrangement should be directly visible and access- ible from end to end, whence it follows that the closing in of plumbing with wood should be avoided. Where the closet fixture is boxed in, the enclosed space serves as a receptacle for dust and dirt, while drop- pings from careless usage get inside the wood-work and develop bad odors. These odors increase with time, since access to their cause by the great natural purifiers, light and air, is prevented. In addition, plumbing should not be located against an outer wall in cold climates, since this arrange- ment greatly increases the danger of freezing. The mere recapitulation of these points shows the many practical difficulties to be met with in plumb- ing, and shows the necessity for careful forethought and intelligent super- vision in its installation. It is not suiJicient for a quartermaster to assume that because a contract has been made to introduce fixtures all that is necessary has been done, nor does it always follow when plumbing is com- plained of that a broken pipe or leaky joint is the only imperfection. Besides the provision of barrack latrines and water-closets for officers' quarters, it is essential that the habitations of enlisted men be provided with sanitary plumbing and drainage, not only for the greater comfort and welfare of their occupants, but also because of the manner in. which un- sanitary conditions anywhere in the post react upon the health of the gar- rison at large. In the absence of drainage and sewerage, the most unsan- itary conditions in a post, with respect to the disposal of excreta and liquid waste, are generally to be found in connection with married soldiers' quarters. WATER-CLOSETS AND WATER-CLOSET APPARATUS. Location and Arrangement of Water-Closet Latrines. — This sub- ject is one of much importance to the military sanitarian, since improperly located latrines and poorly installed fixtures may be a cause of grave in- salubrity. The latter point is of special importance in our service, in which the latrines are too frequently in the same buildings in which the men live, sleep and eat; while in many foreign armies, as in those of Great Britain, France and Germany, the latrines are located in special de- tached buildings, between which and the barracks there is complete atmos- .pheric severance. Of the two arrangements, the latter is much to be preferred. It may be improved, however, by the addition of an airy cor- ridor, through which the latrine may be reached from the barrack by the soldier without exposure during stormy or inclement weather. This separate latrine-building should be located to leeward of the barrack, and at a distance sufficient to prevent any nuisance from arising through its use, yet sufficiently close to be easy of access. In our own service, a com- bined lavatory, bath-house, water-closet and urinal, in a detached building, has recently been approved for use in small posts, particularly those in connection with coast defences. The arrangement, shown in the accom- DISPOSAL OP EXCEETA, SEWAGE AND REFUSE. 561 panying illustration, is somewhat crowded and is not free from other criti- cisms, but it represents an endeavor to accomplish as much as possible with a limited appropriation and is a marked sanitary improvement over the plan of putting the conveniences in the barrack-bmlding proper. This detached structure is intended to meet the needs of one hundred men. ^19-'0^- I -lO-'O^ s|* ifi--^ i._._i In the majority of barracks of more recent constraction, where water- carriage is employed for the removal of waste, the latrine and lavatory fix- tures are placed in the basement of the building. This arrangement, as just noted, is undesirable from a sanitary standpoint, although more eco- nomical; wherever it is employed, at least the space utilized for this pur- pose should have three outside walls, so as to permit the entrance of as much fresh air and sunlight as possible. This is a simple sanitary matter 36 562 THEORY AND PRACTICE OF MILITARY HYGIENE. which can always receive consideration in the planning of barracks, yet one which has unfortunately not been always considered in. later plans. A type of this less desirable arrangement is seen in the accompanying plan of the barracks lately constructed ; in which the row of water-closet seats is placed against a dead inside wall, and light and air have access on two sides only. The installation of lavatory and water-closet con- I § S p. veniences in casemates, as has been done at Forts Warren, Adams and other sea-coast fortifications, should be prohibited, and such fixtures as are already in position should be removed and' placed in special buildings erected for this purpose. Casemates used under such conditions are always damp, foul-smelling and badly ventilated. The free opening up of latrines to light and air should be insisted on. The materials used for the construction of latrines should be such as are solid and impermeable. In the French army, brick and corrugated iron are solely employed for such purposes, the angles of the walls being rounded DISPOSAL OF EXCEETA, SEWAGE AND EEPUSE. 563 and the walls and floors being impervious to moisture. Wooden floors ■ should never be used in latrines, but cement or some similar non-absorbent material is to be employed. The windows in the latrine should extend to the ceiling, and the building or space should be efficiently ventilated. Comparative privacy should be afforded by stalls having louvred partitions, and if the rows of seats face each other there should be a movable screen four or five feet high between them. Doors should not be used with these stalls, as they are liable to become dirty and contaminated with faecal mat- ter. All partitions should be no more than six feet in height and should be cut away for the distance of a foot above the floor, so as to permit the free circulation of air and more ready cleansing. In winter, such latrine ■closets must be heated ; not only for the comfort of their visitors, but also to prevent injury to the plumbing fixtures through freezing. An abundant .supply of water should be available, while the fixtures and plumbing should be of the simplest character. All latrines should be provided with lavatory facilities, so that washing of the hands may be practicable. It should not be forgotten that unless latrines are convenient and comfortable, the men wiU put off resorting to them as long as possible, thus favoring the production of constipation with its train of evils. With respect to the capacity of the latrines to be provided, regulations for the British army require that there shall be five latrine seats and five urinals for each hundred men. This is certainly the bare minimum re- quired. While there is no standard in this respect for our service, it is ■customary to install seven or eight water-closets and four or five urinals to each company of one hundred men. The allowance of latrine-seats in the French and German garrisons is much lower than in our own service. The evUs of an insufficient allowance in this respect are obvious. Night-Latrines. ^ — In the French and British armies, where the latrines intended to receive the excreta passed during the day are located in de- tached structures, special provision is made for the disposal of sjich as may be passed during the night. Detached latrines are regarded as being a possible source of disease through the exposure involved in their use by partially-clad soldiers at night, and a circular issued in the French army, in 1895, called attention to the greater liabiKty to brdnchitis, pneumonia and rheumatism which it was thought resulted from such exposure. For this reason, it is required that one urinal and one water-closet are to be provided in the barracks of each company for night use; in the British army, no means for the disposal of the solid excreta are provided in bar- racks, but each squad-room has a night-urinal directly connected with it. These night-latrines and urinals are kept locked during the day. Where water-carriage is not available, urine-tubs and dry-earth closets or close-stools are used in the British and French armies. These are re- moved at reveiLLe and replaced at night. They are generally located in well-ventilated rooms or in projecting closets built out from the main barrack-building for this purpose. Night-latrines are of course unnecessary where the water-closets and urinals are situated in the barracks. If properly located in detached struc- tures connected with the barracks by covered passage-ways, the latter can be closed in at the sides by movable sashes during night time or inclement ■weather. 564 THEOEY AND PRACTICE OF MILITARY HYGIENE. Fig. 279.— Pan-closet. Water-Closet Fixtures. — In the selection and installation of water- closet fixtures for use in military posts, it is to be borne in mind that the-- apparatus should be simple and sohd ia construction and easy in respect to opera- tion and the maintenance of cleanliness. Apparatus of complicated character, or such as appears liable to be readily broken or get out of order, should be rejected at the out- set, and the same also applies to fixtures- the efficient operation of which requires special care or which is directly dependent upon human intervention. The force and volume of water supplied should be suffix cient to sweep everything out of the receiv- ing basin and maintain its cleanliness, while the shape and capacity of th& latter should be such as to allow the excreta to fall free of the sides and di- rectly into water of such depth as to cover the discharges. In general, a good type of water-closet is limited to such patterns as have a free water-way from the bowl to the soil-pipe, depend- ing for their trapping and the retention of the necessary water on the elevation of the overflow point. A large number of forms of water- -closet apparatus have been devised, these varying more or less in detail but conforming in general to one of several, main types. Among these, the pan-closet is one of the older models. This apparatus violates every one of the essentials agreed upon by sanitarians with respect to water-closets, and has only its cheap- ness to recommend it. It is mentioned because a few closets of this pattern are- still to be found in some old posts, though they are no longer installed and are being' gradually replaced by more modern pat- terns. This apparatus consists of a hemispherical pan surrounding the open bottom of a conical receptacle ; the pan holding a certain amount of water and being intended to form a water-seal or trap. Frequently, from failure of water, defective apparatus or rusting of the pan, the latter is empty, so as to give free passage to noxious gases. From an insufficient supply of water delivered in an improper way, the container and pan are continually smeared with excrement. The closet pipe usually Ftg. 280.— Valve-cloaet. FIG. 281.— Plunger-closet. DISPOSAL OF EXCRETA, SEWAGE AND REFUSE. 565 Fig. 282.— Long-hopper Closet. terminates in a D trap, from which foul gases arise when the pan is drawn back. The apparatus is also very liable to get out of order. The valve-closet is a slight improvement over the pan-closet, ia that its receiver is smaller and of better shape and contains a greater volume of water. Otherwise, it is exposed to much the same objections as apply to the pan-closet; its plug, in addition, being liable to leak and thus fail to keep a supply of water in the receiving iDasia. The plunger-closet is constructed on much the same general principles as the valve-closet, though differing from it in form and a number of par- ticulars. In this closet, the outlet of the bowl is at the side instead of di- lectly below, and is closed by a heavy piston, on the raising of which the con- tents are discharged into an S-shaped trap leading into the soil-pipe. This •closet is a much better form of ap- paratus than the pan or valve-closets, I)ut has several serious defects. While the basin holds a large volume of water, flushing is very inefficient. Leakage may occur from clogging with foreign- material or the retention of paper between the closet-pipe and the plug, when the latter fails to close the outlet completely. The plug also "becomes very foul, cannot be cleaned and serves as a direct source of at- mospheric contamination. The long- and short-hopper closets are most simple in construction and have no mechanical parts to get out of order. This type of closet consists •of a plain bottomless bowl, of different heights, set on a trap which opens into the soil-pipe. The water en- ters by a rim flush, generally from an overhead tank. There is no standing water in the hopper clos- ets, so that their sides are neces- sarily fouled by use — hence their efficiency is largely influenced by the amount of water used for flush- ing and the manner of its distribu- tion over the sides of the receiving basin. With the hopper closets of this type, the water-seal is too small to withstand even a very slight evaporation or air-pressure, and they are noisy in operation. The short hopper is the much better pattern of the two, as the level of the water-seal is nearer the seat and the trap is in view. Various modifications of the short-hopper or so-called "wash-down" filoset have been made, of which one of the best is the "Deluge," in which a Fig .—"Deluge" Closet. 566 THEOEY AND PRACTICE OF MILITARY HYGIENE. flushing rim is so arranged that the water flows in a direction and manner which ensm'e the basin being constantly scoured and kept clean. In the later forms of this apparatus, the cone shape of the hopper is discarded, and the back is made vertical or recessed, so that the excrement drops into the water of the trap- and not upon the side of the re- ceiving basui. A much used and very satisfactory form of closet, of this general type, is the "Dececo." To improve the scouriug efi'ect of the modified short-hopper type of closets, as described above, a number of changes have been pro- posed. One of the best of these is. Fig. 284.—" Deluge " Closet, with Recessed Back. seen in the " Century " closet, in which the service-pipe from the flush-tank has two connections with the closet, one leading into the flushing rim of the basui in the usual manner, while the other discharges into the longer arm of the siphon pipe. One stream thus scours the basin, while the other rushes down the siphon pipe, starts siphonic action and empties the ba- sin; the latter being refilled with clean water by a simple after -flush arrangement of the tank. In the "Twycliffe" closet, besides the flushing stream, a consider- able quantity of water is forcibly driven into the water-seal, so as to cause siphon- age and at the same time mechanically assist in the evacuation of the contents of Fig. 285.— "Dececo " Closet. Fig. 286.— "Century" Siphon-jet Closet. the closet. Some of these fixtures designed to give a quick and powerful flush of water are open to objection, under some condi- tions, by reason of excessive noisi- ness of operation. A much less satisfactory form of apparatus than the short-hop- per water-closets is the so-called " wash-out " type, of which there are several modifications. In these closets, the excreta are re- ceived in a shallow basin con- taining water, over the rim of which the contents are carried, into a trap underneath, by a sud- den and powerful flush of water. DISPOSAL OF EXCEETA, SEWAGE AND REFUSE. 567 Fig. 287.— TwyoUffe Siphon-jet Closet. The objections to this type of closet are many. The water in the receiving basin is not of sufficient depth to cover the solid dejecta ; and if the rim is made higher to avoid this faiilt, the contents may not be at once carried away unless the flush be very powerful. The flushing is often attended by spat- tering, and the operation is noisy. The trap is hard to clean, inconvenient of access and its seal is very shallow, being readily destroyed by siphonage, evaporation or incorrect setting. The pipe-surface between the basin and water-seal is easily fouled and difficult to clean. All these forms of closet are made in earthenware, for the better main- tenance of cleanliness through the smooth interior surface thus afforded. This material has 'the disadvan- tage of being readily broken by rough handling, and, to prevent accident of this sort, other forms of apparatus, made of enamelled iron, have been devised to take the place of the individual clos- ets where the necessities of a large number of persons must be provided for. Common troughs are used to a considerable extent for the re- ception of excreta; these con- necting with the drain by a trapped soil-pipe and being pro- vided with a supply of water. This system in its simplest form is used in some foreign armies, a trough receiving the dejecta and a certain quantity of water. A trapped soil-pipe opens from one end of the trough, being closed by a plug; the latter is pulled up sev- eral times daily by a soldier detailed for the purpose, when the contents of the trough are rapidly discharged. Sufficient water is then allowed to run into the trough to replace that which has been drawn off. An arrangement similar to the above is used at Fort McDowell, where it has been found to be unsatisfactory. Where flushing oc- curs at such infrequent intervals, the trough practically becomes a small cess- pool; the water in the trough only partially retaining the odor of the ex- FiG.289.-oommon washout Closet. creta. A great improvement consists Fig. 288.— Lambeth Wash-out Closet. 568 THEOEY AND PEACTICE OF MILITARY HYGIENE. ia the use of an automatic flush-tank, by which the trough is flushed out at intervals of about ten minutes and its contents are carried away. The re- ceiving trough is usually provided with a horizontal flush-pipe running along its rear wall and having fine holes so placed as to cause this surface to be washed down during the general flushing. This horizontal pipe is located immediately under the lid, and is supposed to be out of the way of the dis- charges. As a matter of fact, however, it is usually spattered with diarrhoeal discharges, and becomes very foul without frequent mechanical cleansing. Nearly a hundred of these latrine-troughs have been installed in our ser- vice, and nearly all have been subsequently torn out as being unsatisfactory. The trouble appears to lie in the fact that the receptacles are uniformly made too narrow by the manufacturers. If they were made six or eight inches wider, so that faecal discharges could not be projected against the horizontal flush-pipe or the back of the latrine-trough, the arrangement would prob- FiG. 290.— Trough Water-closet. ably be the best which could be used in the military service. The exist- ing faults do not depend upon the system as a whole, but upon defects of construction. The seats in water-closets, whatever the special system employed, are best cut away in the shape shown in Fig. 166 to limit the liability of fouling by the discharges. The ordinary openings are also not infrequently made too small, and under such circumstances cleanliness of the seats can- not be maintained. To prevent absorption by the wood of the seat of organic matter resulting from excretal contamination, as well as to limit its impregnation by the odors arising from the latrine-receptacle, the render- ing of the wood impermeable on both sides by the use of paraffine, accord- ing to the method already mentioned in connection with floors, is highly advisable. By the use of this process the cleansing and disinfection of the latrine-seats would be greatly facilitated. All seats in water-closets should be hinged, so that they can be turned up out of the way for cleansing or to prevent soiling if the fixture be used as a urinal. As with plumbing generally, water-closet apparatus should be freely exposed for inspection DISPOSAL OF EXCRETA, SEWAGE AND EEFUSE. 569 and should never be boxed in. In the care of water-closets and the pre- vention of bad odors, scrupulous cleanliness rather than the use of deodor- ants is required — and this can be accomplished by scrubbing and thorough flushing with water. In the German army, civilians are employed to do police work of this character — ^the cleanly condition of the latrine being verified several times daily by non-commissioned officers. There would seem to be no reason, however, where water-carriage removes the excreta both promptly and efficiently, why the comparatively small amount of attention necessary with such latrines should not be required of the men themselves; the care of earth-closets being obviously quite a different matter from that of water-closets. The throwiug of anything into water- closets, other than materials which they are intended to receive, should be prohibited on account of the obstruction thus frequently produced. Thus at Fort McPherson, in 1898, the water-closets were reported as having been choked with socks, handkerchiefs and even drawers, while sticks, bottles and similar articles are not rarely forced into the pipes. Hard glazed paper, which does not readily soften down in water, has sometimes been a cause of stoppages, and for this reason the issue of toilet paper, at present under trial — aside from the comfort and cleanliness afforded by its use — has much to commend it. This paper should be kept on hand in the latrine-stalls and distributed by special contrivances to pre- vent wastage; each man should not be compelled to carry his own supply, as is at present the case. There may be times when this individual supply is missing or insufficient, and the soldier is thus put to unnecessary discomfort, and his person and surroundings to undesirable pollution. An allowance of toilet paper is issued ia the British army and in the German military hospitals ; other services appear to make no provision in this respect. In this connection, it may be noted that no small number of military sanitarians in foreign armies advocate the use of the squattiag position dur- ing defsecation. In the French army, in barracks of recent construction, provision is made only for such a position. For this purpose, an earthen- ware arrangement is used by which the men are compelled to place them- selves directly above the opening which is intended to receive the excreta. Places are specially arranged for the feet, and the opening is made large so as to avoid the arrest of any portion of the faecal discharges. With this arrangement, the m^ine voided during defeecation is discharged forward, often being passed upon the seat or the floor in front of the arrangement for defsecation. To provide for the latter, the floor in front of the apparatus is made to slope to a central point, whence a trapped drain allows the escape of any fluids into the soil-pipe below the closet water-seal. The whole arrangement is made of impermeable material, and is kept clean by scrub- bing and sluicing down with a hose. The squatting position for defsecation is advocated on physiological grounds and also as being cleaner and afford- H ^ s Fig. 391.— Arrangement of Water-closet Fixtnre lor Squatting Position, as Used in the Frencli Army. (Alter Layeran.) 570 THEOEY AND PEACTICE OF MILITARY HYGIENE. Fig. 292.— Bowl Urinal. ing less opportunity for infection by contact. The first point may be dis- regarded ; the possibility of infection through contact with latrine-seats must of course be admitted, but such cases are probably extremely rare in actual practice. The whole matter would seem to depend merely upon the main- tenance of a proper standard of cleanliness and an efficient sanitary police. Where these are main- tained, the sitting posture is undoubtedly more com- fortable. Squatting on seats of the ordinary char- acter, as provided in our service, inevitably results in their befoulment. It can be prevented by plac- ing a board horizontally in its long dimension above the seat at about the height of the shoulders when in the sitting posture; the board being made to in- cline downward as well as backward. Urinals. — These should be installed under the same roof as the la- trines. It is desirable that they be few in number or that the surface soiled by the urine be as small as possible. They should be constructed of first-class materials and with great care and skill; the latter not being usually possessed in sufficient degree by extra-duty men. No special type of urinal is imiform for our service, and several patterns are in use. Of these, the earthenware-bowl system is largely employed. With this arrangement, however, soiling of the floor always occurs, since the men do not stand Sufficiently close to the bowls during urination. This might be avoided by placing a strip of impermeable material about two inches high and twelve to fifteen inches wide, at such a distance from the bowl that the men would necessarily have to stand upon it dur- ing urination. With such an enforced position, the contamination of the floor with urine would be largely avoided. Since the flooring will be more or less contaAinated in any case, the best urinals are probably those which have an impermeable floor and verti- cal receiving siu^face and a gutter which collects and removes the urine and flushing-water. For the impermeable receiving surface, plates of glass, painted gray on the side nearest the wall, have been much used during the last few years. This material is readily cleansed, but is liable to fracture under rough treatment. Marble is costly and too permeable for use. All things considered, the best material is probably slate; which is all but impermeable, is cheap and can be readily worked. It is not necessary to have the urinal divided into stalls, since the side walls of these are often soiled by urine and are difficult to clean. The floor of the urinal should be DISPOSAL OF EXCRETA, SEWAGE AND REFUSE. 671 constructed of slate, should be at least three feet wide and should have a slope of at least one inch toward the receiving surface, where it should fall away to form a gutter. The pipe into which the gutter discharges should of course be trapped ; this pipe being guarded by a wire screen to catch £iny foreign articles which may find their way into the urinal. Instead of the simple arrangement just described, a form of m-inal intermediate between it and the bowl system is used in several foreign armies ; the flush-water and urine passing into a trough about two feet above the floor. This trough is both imnecessary and undesirable. The near side of such a receptacle is sure to be soiled with urine, yet is not reached by the flushing-water and can be cleaned only by hand. Further, since a certain amount of urine falls on the floor and its disposal has to be provided for under any circumstances, the whole might just as well be de- posited and removed in this manner, particularly since this is usually more thoroughly and satisfactorily accomplished than where only a small part of the urine requires attention. To wash the receiving surface of the urinal, the water may run inces- santly or be discharged intermittently — the latter arrangement being the better. Where the flush- water runs continually in small quantity, it is rare that all the receiv- ing surface is washed down, since the water forms currents and leaves little dry islets. On these, urinary deposits accumulate and go on to decomposition, so that the urinal, in spite of a constant flow of water, may appear unclean and will usually have an un- pleasant odor. With flush-tanks this incon- venience is avoided. All the surface is washed down by a copious dis- charge, and the interval between flushings is not sufficiently long to allow an accumulation of uriue- salts. The flush-water is discharged from a hor- izontal pipe pierced with numerous small holes, the jets from these being directed against the slate by a strip of zinc so placed as to prevent splashing. Solid matters rarely give rise to the bad odors sometimes noticed in water-closets, but these are chiefly dependent upon the retention and de- composition of urine. Hence urinals should be regularly cleaned, and all deposits of urine-salts removed as soon as formed. For this purpose. Fig. 293.— Flush-down Urinal. 572 THEOEY AND PEACTICE OP MILITAEY HYGIENE- automatic flushing can never take the place of manual cleansiag with hot water, soap and a stiff brush. An unpleasant odor about a urinal invari- ably implies an iuefflcient police ; unfortunately this is too rarely appre- ciated, and such efforts as are made to diminish odors are usually limited to the openiag of wiudows and the use of deodorizing disinfectants. The disinfection of urinals, however, except in hospitals, is rarely required. The water supplied to urinals is sometimes rich in iron-salts, which, together with those of the urine, leave unsightly stains or incrustations on the fixtures. These can readily be removed by scrubbing with a ten per cent, solution of hydrochloric acid. This acid also promptly neutralizes any ammoniacal and mal-odorous deposits, and can be used without injur- ing the apparatus. Where a supply of water fails the urinal, the exposed surface should be greased to prevent the deposition of urinary sediment. nONT u-cvATioil Fig. 294.— Flusb-down Trough TJrlnal. This is done by daily passing a mop dipped in oil — usually linseed oil — over the exposed surface. The small amount of oil carried down by the urine forms a pellicle over the fluid in the traps, and largely prevents the bad odors which might otherwise arise therefrom. This use of oil in con- nection with urinals is largely employed in the Austrian army. It is par- ticularly of value for urinals where there is no water-carriage, as in posts where the dry-earth system is employed. Flush-Tanks. — For the better scouring out of water-closet fixtures and traps, the water to be supplied for this purpose should be of consider- able volume, and should be delivered with a sudden rush rather than more gradually. Where the washing out of latrine fixtures is concerned, econ- omy in the use of water, within certain limits, is misplaced. For single water-closet bowls, a flush of two and one-half gallons gives good results in the better form of apparatus, while as much as three and one-half gallons may be required for the poorer type of closet. Beyond the latter amount, any excess may be regarded as wastage. With latrine-troughs, the allowance of water for a single flushing of course depends upon the length DISPOSAL OF EXCRETA, SEWAGE AND REFUSE. 573 and width of the receptacle and the depth of the water standing in it. With trough-closets of the ordinary type, a flushing allowance is required of about three gallons to each seat. For the supply of a sufticient quantity of water without wastage and in the most efficient manner, the use of flush-tanks is now general. These may be automatic in their periodical action or may be mechanically started into operation when required. The tank is usually placed about six feet above the level of the water-closet seat. For single bowls, the dis- charge-pipe should be one and one-half inches in diameter; for trough- latrines, the si^e of the pipe obviously depends upon the number of seats in the fixture. A discharge-pipe of insufficient diameter impairs or destroys the efficiency of the flush. In cold weather, care must be taken to prevent freezing of the water in flush-tanks, more particularly those of non-automatic operation ; but under ordinary conditions, this accident is not liable to occur with tanks which automatically discharge their contents with considerable force at frequent intervals. Besides properly modifying the character of the flush and preventing waste, flush-tanks are of sanitary value from the fact that by their use the direct sup- ply of water to closets from the water-pipes is avoided. Flush-tanks for sewers, depending on siphonage for their operation, differ from those used in connection with water-closets only in the magnitude of their dimensions. For general military use, copious flushes auto- matically discharged at regular intervals are prefer- able to those depending for their operation upon attention from the men themselves. The great ma- jority of flush-tanks operating automatically are constructed on the plan of the annular siphon de- vised by Eogers-Field. As shown in the accom- panying illustration, this apparatus consists of two reservoirs, A and B, communicating by a vertical pipe C, having its upper opening narrowed by a circular flange projecting downward. The pipe C is covered by a metal cap D, which descends nearly to the bottom of the tank A, leaving a space between the pipe G and itself. This cap is pierced at (? by a small opening. The pipe E discharges into the closet to be flushed. A faucet, which is not shown in the figure, allows a small jet of water to discharge constantly into the reservoir A. After the tank has been once flushed, water remains in the lower reservoir B at the height n, nJ . The water which constantly passes into the reservoir A accumulates, and when its level has passed the orffice the air in the pipe G is compressed more and more as the quantity of water in the reservoir increases. The com- pressed air forces back the water in the pipe C until a moment arrives when the air is forced out through the bottom of this pipe by the increasing pressure above it, water rushes in and rapid siphonage occurs. When the water has been lowered in the tank A to the level of the orifice 0, a cer- tain amount of air passes in, gradually destroys the siphonic action and prevents the water-seal in the receptacle B from being lost. This flush- tank must be set perfectly level to ensure a powerful action, since if it leans to one side the water passes over the lower edge of the inner tube without Fig. 295.— Bogers-Fleld Auto- matic Mush-tank. 674 THEORY AlfTD PEAGTICE OF MILITARY HYGIENE. ITg. 296.— Siphon-Flusli Used in tbe French Army, Showing Wa- ter in the Water-seal. strong flushing. By regulating the flow of water into automatic flush-tanks of this character, their regular discharge can be accomplished at such in- tervals as may be desired. A simple modification of the above flushing-apparatus consists ia the use of a curved tube, like an inverted U , which passes through the bottom of the tank, rises to near, the top and then again descends so that its open mouth is shortly above the bottom. When the level of the water iu the tank rises to the top of the curve, the dis- charge begins and continues until all the water has been siphoned ofl'. Sometimes this single tube is replaced by a number of smaller ones, so that the tank is emptied with great rapidity and force. Automatic flush-tanks are also made in such a manner that the action of a float oper- ates to lift a valve and allow the escape of the water after it has reached a certain height. A siphon-flush which is much used in the French army, as shown ia the accompanyirig fig- ures, is a curved pipe, A,B, C, D, with its long branch, B, C, D, having its extremity curved in such a manner as to pre- sent a trap at G constantly full of water. At the point d, the tube BdT branches off; its upper end opening into the free air, while the lower end extends a distance of some centimeters into the water-seal. This tube (dT) is itself pierced by an orifice, V, at which is fastened with solder a pipe of very small caliber, twice curved on itself, and entering the other part of the siphon at the point u. The bottom of the curve of this pipe is pierced with a small hole at o, having a diameter much smaller than that of the tube. The apparatus is placed in a tank having a bottom {xy), some centimeters below the orifice A of the small arm, which also pos- sesses a curve for holding the water, C, and a discharge pipe, CD. As water flows into the reservoir, the orifice A is covered. The water rises little by little above the orifice A in the small branch of the siphon to the same height as in the reservoir, without the press- ure changing in the siphon, for the air which is displaced by the coliomn of ascending water escapes by the orifices o and u. But when the level of the latter has attained the orifice 0, the air of the siphon is imprisoned and compressed, and its pressure above that of the atmosphere is each instant measured by the difference in level between the water in the siphon and in the reservoir. The level of the water gradually rises in the reservoir and in the branch oa, until it finally attains the point a. The tube uoa thus forms a siphon. The column of water oa is then precipitated into the branch a F, if any more water passes into the tank and increases the pressure ; but as the orifice o which connects the reservoir and the tube is less than the diameter of the latter, the water Fig. 297.— Siphon-Flush Used in the French Army. Condition immedi- ately prior to the commencement ol slphonage. DISPOSAL OF EXCRETA, SEWAGE AND KEFUSE. 575 Fig. 298.— single Valve Flush-tank. which passes through it is insufficient to feed the siphon. The column ao is quickly broken, and is no longer sufficient to equ^li^e the pressure of air in the siphon. Upon this, the level of the water in the branch AB rises suddenly, sipbonage begins in the large pipe, and the tank is emptied down to the level A. The tube BT permits the re-entrance of air into the lower part of the conduit, for the re-establishment of at- mospheric pressure after flushing. On the other side, air is drawn in through the openings a, and u, thus permitting a certain volume of water to remain in the trap C. While automatic flush-tanks are pref- erably used in latrines frequented by a considerable number of men, for certain uses, as for quarters and hospitals, such tanks would flush the closets more fre- quently than is necessary and thus waste much water. Under such cir- cumstances, it is desirable to have flush-tanks which can be set in action only when the need for their use exists. Many varieties of these tanks are now on the market, and it is useless to multiply descriptions of apparatus of which nearly every manufacturer has his own model. With this system, each closet should have a separate tank, usually made of iron and discharged by siphonage. A float on the end of a long lever operates mechanically to shut off the water-supply, when a proper level has been reached, by clos- ing the valve of the faucet. A short puU at the chain will start the action of the siphon, when the contents of the tank are rapidly discharged. The overflow-pipe irom the tank is best made to discharge through the wall into the outer air ; imder no circumstances should it open into any pipe connected with the water-closets. While the automatic flushing of urinals with a disinfectant solution is rarely necessary, it can readily be accomplished by means of the simple arrangement shown in the accompanying illustration. In this, the tank A is an automatic flush-tank, while 5 is a smaller tank containing a disinfectant solution of considerable strength. Through a small aperture in the bottom of B, this disinfectant solution passes slowly into the small reservoir C and rises in the small cahber siphon- pipe to the level of the fluid in B. The tube d allows the entrance of air into the lower reservoir C. With ■each flush of the tank A, the water so discharged as- pirates the strong disinfectant in C into the main dis- charge pipe, and dilutes the latter to proper strength before the whole is flushed through the urinal. The size of the two pipes and tanks should be so proportioned that the latter are emptied at about the same time; the strength of the disinfectant solution nsed should be such t^^at when the contents of the tanks A and G are mixed, the resultant is an efficient germicidal solution. ■Apparatus for the Automatic Dislnleo- tion of Urinals. 576 THEOEY AND PRACTICE OF MILITARY HYGIENE. Liquid Waste. — Waste-water from kitchens, baths and lavatories, at small imsewered po^s, has not rarely been thrown out on the ground near the barracks — a method of disposal which results in constantly increas- ing sanitary evils. While this disposition of foul water may not at once react upon the health of the garrison, it cannot but ultimately exert an unfavorable influence in this respect. Thus from Fort Niobrara, in 1892, it was reported that soil pollution had gone on to an extent which resulted in the constant presence of strong foul ^dors ia the rear of the barracks — comment made at department headquarters on this report being that the health statistics of this post were such as to confirm the belief of extensive soil pollution. Even ia posts in which the liquid wastes are carefully removed from barracks and officers' quarters, no such precautions are com- monly taken with respects to the quarters of married soldiers, and the waste water from the kitchens, laundries and baths of such habitations is gener- ally poured on the ground. This method of disposal is highly undesirable, since ground constantly saturated with liquid filth soon becomes foul- smelling and furnishes favorable conditions for propagation of the germs of disease. There is certainly no reason why a practice which is usually strictly forbidden to the military portion of a garrison should be tolerated among its civilian followers. Improving on the disposal of liquid waste by its deposition on the ground, slop and waste-water barrels, slop-carts and open drains have been employed — but even their use is accompanied by a gradual but nevertheless positive contamination of the soil in the vicinity of quarters. In a num- ber of instances, liquid wastes have been removed from posts by special drains and discharged into tight or leaching cess-pools. This method of disposal is undesirable, and where a general sewerage system exists the pipes carrying the liquid wastes should of course be discharged into it ; but in their arrangement such waste-water pipes should be kept separate from those of the water-closet system and should never open into soil-pipes. In Eng- land, it is required that pipes conducting waste-water shall not connect directly with any drain, but must discharge into the open air, about eigh- teen inches above a grating covering a good water-trap leading into the main drain. The waste-water pipes are usually three inches in diameter, with three-inch siphon water-seals. Bath-tubs, wash-basins and laundry fixtures are usually provided with small overflow-pipes, which are either themselves trapped or are connected with the main outflow on the near side of the bend. Such pipes gradually accumulate deposits on their interior surface, which may become very offensive — and hence great care as to their cleanliness should be observed. Where a lavatory or bath is trapped by a sigmoidal bend, it should not be forgotten that odors may be able to enter from the trapping water being withdrawn through siphonage. If these odors are marked, pipes offending in this way should be traced down to the points of discharge, so as to de- termine if they wrongly open into soil-pipes. Kitchen sinks have a large outflow, trapped close to the sink and pro- vided with a strainer. As the trap is liable to become choked with sedi- ment and accumulations of grease, there is usually a screw-cap on its con- vexity by which it may be cleaned. This carria^ of liquefied grease by hot water is often a cause of much annoyance m connection with the DISPOSAL OF EXCRETA, SEWAGE AND EEFUSE. 577 removal of liquid wastes from the kitchen, since this grease, imder some circumstances, may be carried to a considerable distance along the outflow before it is deposited, and may ultimately destroy the carrying capacity of the pipe through reduction of its lumen. The disposal of greasy water is such a serious sanitary problem that French army regulations require it to be placed in tight metal receptacles for removal, while the remaining waste-water can be discharged directly into the sewers. The deposit of grease may be largely prevented or removed by a frequent flushing of the ■kitchen waste-pipes with a strong, hot solution of lye. This solution, made in the strength of one-half pound of lye in two quarts of boiling water, should be poured into the trap at night and allowed to remain imtil the next day — no other water being discharged into the sink in the mean- time. Several gallons of hot lye solution of one-half the above strength should be flushed through the pipe immediately on the following morn- ing. The ammoniacal fermentation of water-closet discharges has a con- siderable effect in preventing deposits of grease in the main drain. To prevent deposits of grease in the pipes, a grease-trap or intercepting chamber is sometimes employed. This is generally made of iron or stone- ware, has a tight cover and should be ventilated. The size of the cham- ber is proportioned to the amount of gi'easy water to pass through it, so as to prevent too rapid displacement of the contained water. Usually the grease- trap is divided by a central partition, dipping several inches into the water. The hot, greasy water enters at one side of this partition, while a correspond- ing quantity of cold water escapes through an outlet on the other side of the partition. The liquefied grease, on entering the trap, is chilled and solidified by contact with the large bulk of cold water and rises to the sur- face, where it is prevented from passing out by the vertical partition. Cleansing of such traps is periodically required, for unless carefully looked after they are little better than cess-pools and may become a serious nuisance. They are certainly needless except in the case of large kitchens, for with small establishments cleanliness on the part of the cook and efficient flush- ing with lye solution will keep the pipes clean. Under certain circum- stances, the operation of grease-traps may be inefficient. Thus at St. Francis Barracks, in 1896, the choking of the drain-pipe from .deposits of grease was reported despite the presence of grease-traps. The coating of grease was foimd to be generally distributed over the entire pipe, varying from a minimum thickness of one and one-fourth inches to one which almost completely obliterated the lumen of the pipe. This obstruction of the pipes was probably dependent upon inadequacy in the size of the grease- traps and a high temperature of the soil, by which the greasy water escaped into the drain before its grease was solidified by chilling. The water- supply of this post was also very hard and contained much sulphur, thus greatly favoring the precipitation of greasy matters. Grease-traps should always be located out of doors, and never, as at old Fort Mackinac, placed within buildings. In very cold climates this necessity, with resulting liability to freezing, places obvious restrictions on the use of grease-traps, and under such circumstances particular care on the part of cooks is necessary with respect to the disposal of greasy wastes. 37 578 THEORY AND PRACTICE OE MILITARY HYGIENE. DISPOSAL or SEWAGE AND REFUSE. The ultimate disposal of sewage is a sanitary problem which is variously solved according to the environmental .conditions obtaiauig ia the com- munity and the character of the material requiring disposition. Although liquid wastes alone pass into the sewers in a few posts, the term sewage may be understood for present purposes to iaclude the solid and liquid excreta, storm-water and the waste-water from kitchens, baths and lava- tories. Sewer-water thus varies greatly in its composition; being some- times turbid, foul-smelling and highly impure, and at other times contami- nated only to a relatively slight degree. Thus one ton of London sewage is said by Lawes to contain only two or thr.ee pounds of solid matter. The quantity of material eliminated by the adult male is generally fixed at about four ounces of solid excreta, by weight, and fifty ounces of liquid excreta, by measure. It is thus evident that the chief question concern- ing the disposal of sewage has relation less to the comparatively small amount of contained organic solids than to the great bulk of fouled water in which they are dissolved or suspended. Whether the solid excreta pass or not, however, the liquid in the sewers always contains more or less ani- mal and vegetable matter. While an exact knowledge of the chemical constituents of sewage may be at times of importance in civil life, this question does not greatly interest the military sanitarian, who, regarding aU. sewage as putrescible and a possible cause of disease, is merely interested in securing its speedy removal and early destruction. Disposal of Sewage into Cess-Pools. — This method of disposal is sometimes employed for small posts, groups of buildings or single barracks. In this method of disposal, the drain or sewer discharges into an excava- tion in the ground; generally walled dry with loose stones and having a floor of earth, but sometimes cemented throughout and hence water-tight. The latter form of cess-pool requires much attention and frequent removal of its contents, best accomplished by the use of the odorless excavator apparatus. As sometimes cleaned out, however, — as was the case at Fort Assinniboine, where the bath- and waste-water from the hospital and bath- house was discharged into tight cess-pools, there to accumulate, ferment and putrefy until the cess-pool was filled to the top — the contents of the cess-pool are merely pumped out on the surface of the ground in the vicin- ity, to soak at once into the ground or drain away, as the character of the soil or configuration of the surface may determine. There can be no doubt that the original discharge of such foul water in small quantities on the surface of the ground, where it is promptly exposed to the purifying action of sunlight and fresh air and that of the nitrifying bacteria of the soil, is far preferable to its storage until it has accumulated in large quantity and its noxious qualities have been much increased. Where cess-pools are in use at all, the leaching variety is generally employed. Through the porous walls and floors of such receptacles the liquid constituents of the sewage drain away more or less rapidly, accord- ing to the character of the soil. In very open soils, little but solid mate- rial is retained in the cess-pool, and this is removed from time to time. Various processes for the destruction or utilization of the sludge are employed in civil communities, but none of them, save the use of such solid matters DISPOSAL OF EXCRETA, SEWAGE AND EEFUSE. 579 for fertilizing purposes, have any applicability to the military service. During the operation of cleansing, care must be taken to avoid contamina- tion of the surroundings of the cess-pool with the filth removed. In the majority of cases in which leaching cess-pools are employed, however, the soil surrounding the excavation ultimately becomes clogged with greasy particles; and as no ordinary treatment will free the ground of such ob- structions, a new cess-pool usually has to* be provided. In some soils and with a considerable bulk of sewage, this may become necessary every year or so, and a large extent of ground thus becomes saturated with organic filth. The economical advantage of leaching cess-pools is that the liquids escape readily and cleaning is comparatively infrequently required. This minor advantage is more than counterbalanced by the resulting pollution of the subsoil and the great danger of contaminating an underground water- supply. Cess-pools are always unsanitary and should not be allowed in a military post. If permitted, they should at least be at a considerable distance from habitations and far removed from the water-supply. Prior to their location, the trend of the ground-water should be determined. The drain leading into the cess-pool should be disconnected and trapped, and the latter should be ventilated by a tall outlet shaft — preferably painted black — and a shorter inlet. The location of cess-pools, like that of latrine vaults, should be plainly marked; in default of this simple precau- tion, one barrack at Fort Washakie was lately shown to have been built within three feet of an abandoned cess-pool. Wlien cess-pools are now put into posts, they are usually installed un- der the plea of temporary expediency — but unfortunately, after being once established, they are often retained for long periods or until the nuisance created by their use forces their abolishment. As illustrating this point and also showing the occasional indifference of commanding officers to funda- mental sanitary rules, a system for the disposal of lavatory and kitchen waste-water, installed at Fort Assinniboine in 1896, may be mentioned. In this instance, a pipe carried the waste-water three feet from the wall of the barracks, discharging it into a drain which extended for thirty yards and opened into a leaching cess-pool. The drain in question had its top and sides constructed of boards, but possessed no floor other than that provided by a naturally porous soil. The fluid passed into this drain largely failed to reach the cess-pool, but sank into the soil close to the foimdations of the building. The pipe leading into this drain was untrapped, and, from the greater inside warmth, foul ground-air was drawn into the building. This method of disposal, established despite strong protests on the part of the medical officer, is understood to be stOl in existence. Discharge of Sewage into Bodies of Water. — ^This disposition of sewage is the one generally adopted in sewered army posts. It is ordinarily satisfactory, so far as the post itself is concerned, if the discharge be into a water-course — but under the latter conditions a nuisance may result as re- gards communities farther down the stream, as was recently the case at Fort Logan. Conversely, the disposal of sewage in this manner by towus may result in the creation of unsanitary conditions in adjacent posts ; ' as at Washington Barracks, where the sewage from the city is poured into. a canal which forms one boundary of the narrow reservation, and which is practi- cally an open foul-smelling drain ; or at the Presidio, where sewage from 580 THEOEY AND PRACTICE OF MILITARY HYGIENE. San Francisco is discharged upon a marsh within the limits of the military reservation. Where the sewage is discharged into a water-course which subsequently becomes a source of supply, the dangers of such contamination are, of course, greatly increased. Thus the amount of sickness at Jefferson Barracks, the water-supply of which was formerly contaminated by the sewage of St. Louis, was greatly diminished when a new and pure source of water was secured. The easiest method of getting rid of sewage, however, undoubtedly consists in passing it into streams of considerable volume, where it is at once diluted and its solid constituents are oxidized, become food for fishes and plants, or settle down to the bottom. In western sta- tions, with a comparatively unsettled country, no objections as to this method of disposal have generally been raised ; but as the country develops, and particularly with small water-courses, contamination of this sort may be expected to arouse opposition from the civil communities affected. , Where sewage is discharged into the sea, the resulting dilution of the former does much to destroy its offensive qualities, in spite of the fact that oxidation of organic matter goes on much more slowly in salt than in fresh water. In many instances, however, even where small amounts of soM material require disposal, much difficulty has resulted from the action of the tides and currents. Thus at Port Schuyler the use, as a latrine, of a build- ing projecting over the water had to be abandoned by the command, as the excreta, instead of being removed, were deposited on the beach. Where tidal currents exist, the point of discharge for sewers should be located be- low the post in the direction of the falling tide. The greatest difficulty with such outfalls occurs at low water. As the flow of sewage is contin- uous, under such conditions the best method is to store up the sewage and discharge it by automatic apparatus on a falling tide. It was found neces- sary to install arrangements of this sort at Fort Monroe, where the sewage discharged at certain stages of the tide was cast upon the beach. At this station, besides securing an intermittent discharge, the sewer-pipes are ex- tended into the currents six-hundred feet below low-water mark, and the sewage is thus efficiently carried away from the post. Sewage should never be discharged iuto small tidal estuaries, since it is never carried to any distance but is either deposited on the bottom or cast back on the shore. To prevent the entrance of water into tidal sewers, flap-valves are usually employed, these automatically closing with a rising tide. Sewage-Farms and Ground-Filtration of Sewage. — Where facil- ities are at hand for the purpose, the putrefying animal substances in sew- age can be prevented from contaminating the air, the soil or the water of streams by imitatiag the processes of nature and directly utilizing them as food for plant life, which in its turn may be employed as sustenance for men or animals. This method for the disposal of sewage consists in the discharge of the latter upon or into the soil in such a way that it shall be acted upon by growing vegetation. The soil acts as a filter, straining out the solids ; then by the separating action of the earth-particles, a large sur- face of the fluid is exposed to the action of the air, with oxidation of the dissolved organic matter. This process of destruction is greatly aided by the disintegrating action of the nitrifymg micro-organisms in the soil. There are several modifications of this general method of disposal — the simplest being to screen out the more gross portions of the sewage and DISPOSAL OF EXCEETA, SEWAGE AND REFUSE. 581 distribute the remainder over the surface of the land to be employed for this purpose. The irrigation must be intermittent, so as to allow the soil to drain and receive air and not too greatly raise the level of the ground- water. The son itself should be porous, so that fluids may readily pass through and out of it. The best kind of soil for this purpose is a friable loam ; but even sandy or gravelly soils, when properly managed, will purify sewage. In the case of. stiffer soils, subsoil drainage is usually required. Where this is necessary, the porous drains should have an inside diameter of about four inches, should be laid four to six feet deep and twenty to one hundred feet apart, according to the porosity of the soil. The drains should unite into a single large outlet-pipe at the lowest part of the farm, which may discharge into the nearest water-course. Where . grass is grown as a crop, the solids must be screened out or removed by settling-tanks and should be taken away from time to time. The sewage-farm should, of course, be so located that the sewage may be carried to it by gravitation. The locality selected should be gently sloping; or, better, should have a Fig. 300.— Disposition of Sewage and Vegetation in Sewage-Farms. ridge from which the ground falls away gradually on each side, the irriga- tion being from the top. The sewage is allowed to trickle slowly down through ordinary trenches, provided with dams and gates for its better con- trol. Ponding of the sewage is to be avoided, and no more should be let into a trench at one time than the soil with which it comes in contact can readily absorb. The effect of sewage-irrigation upon the growth of vegetation is remarkable, particularly upon the coarse grasses, cereals and vegetable roots. Italian rye-grass appears to flourish best on sewage farms. Where vegetables are grown, they are usually cultivated on ridges, while the sewage is discharged into the intervening furrows. Sewage-farms, if too near habitations and not properly cared for, may become nuisances from the odors to which they give rise — ^but these are usually not very offensive and soon cease after the sewage once gets on the land. There appears to be no evidence that sewage-farms are productive of disease among those who have them in charge or are residents in their vicinity as is shown by the vital statistics of Berlin and other munic- ipalities. Salad-vegetables from such farms should not be used, nor should the ground be permitted to become swampy and water-logged. A certain amount of labor and oversight is, of course, necessary to ensure the proper operation of sewage-farms, but the expense and labor of this may be partially counterbalanced by the sale or use of the produce. The method of disposal of sewage by irrigation has been employed at Forts Bayard, Bidwell, Stanton, Logan and other existing or abandoned posts. At Fort Logan, the system of disposal by this means was faulty, in that the sewage 582 THEOEY AND PKACTICE OF MILITARY HYGIENE. was used for irrigation only during part of the year, while at other times it accumulated ia a large pool which drained into the Platte Eiver and cre- ated a nuisance. At some posts, the sewage used for irrigation has been composed only of liquid waste ; the solid excreta being disposed of by earth- closets. Eecently, at Port Douglas, the use of the sewage for the irriga- tion of the post garden was proposed. Intermittent downward filtration, as a method .of disposal, differs from that of irrigation on sewage-farms in that it may be considered as the con- centration of sewage at short intervals over small areas of specially chosen and prepared ground. Vegetation is not excluded, but the question of pro- duce is made of secondary importance. The soil should be porous and thoroughly under-drained, so as practically to form a filtering-bed. The under-drained area is generally divided into four parts, each of which in turn receives sewage during a period of six hours. Intermittency of irriga- tion is essential to the success of the method. The sewage turned on the ground is required to be clarified ; since where the crude material is applied, the soil acquires a surface coating of slimy matter which prevents the ab- sorption of liquids and results in ponding. As with ordinary sewage-farms, purification of the sewage is brought about by filtration, oxidation and nitri- fication. This oxidizing quality is especially marked in rich moulds and loam. Nitrification is confined to the limits of temperature within which the nitrifying bacteria are active, being most rapid at about 37° C. ; and these organisms are most abundant in the upper six inches of the soil. With sewage-farms and downward filtration, the effluent water is clean, bright, odorless and palatable to the taste. It contains relatively few micro- organisms and these are almost entirely saprophytic forms ; the amount of chlorine, however, is high. In well-drained land, the clarified sewage ma ybe applied intermittently in the proportion of one acre of ground to the sewage of two thousand people ; the latter being about ten times the number whose wastes could be disposed of on ordinary sewage-farms of equal area. These estimates, however, are only approximate, since the efficiency of the methods depends upon so many variable details. Both methods appear to operate fairly suc- cessfully during winter, though, of course, they are most efficient with a temperature which permits of the growth of plant and bacterial life. The warmth of sewage usually keeps a sufficient amount of soil unfrozen, even in very cold weather, to permit of the absorption of its liquid portions. Subsoil irrigation may sometimes be used for the disposal of sewage from small posts or groups of buildings. By this method, instead of direct- ing the sewage over the surface of the ground by means of ditches, the liquid waste is taken into a system of loosely jointed and porous drains, located six to twelve inches below the surface of the soil, whence it escapes into the subsoil. The system requires the removal of the fat, grease and coarser solids ip the sewage to prevent clogging of the pipes, besides which the latter must be dug up and cleaned at intervals of ten or twelve months. The liquid wastes are generally discharged into the pipes by means of a large automatic flush-tank, so that the penetration of the sewage to all parts of the system may be assured. This method gives fairly satisfactory results under proper conditions, the fluids being largely taken up by the roots of adjacent vegetation. It is not, however, applicable to winter use DISPOSAL OF EXCRETA, SEWAGE AND REFUSE. 583 in cold climates. One objection to this system is that the drainage enters the soil below the level of greatest bacterial activity and the liquid is chiefly dependent upon the mechanical action of the soil, and the utilization of its organic constituents by vegetation, for its purification. Bacterial Treatment of Sewage. — This method has recently as- sumed importance as a simple, practical, efficient and economical means of sewage purification. It depends upon the fact that there exist in nature certain non-pathogenic micro-organisms, broadly divided into those which are aerobic and those of an anaerobic nature, whose function in life, under the conditions that thek names imply, is to convert the solid portions of animal excreta and organic matter into gaseous and liquid forms by a process analogous to digestion. In the bacterial treatment of sewage, the effort is made to create conditions as favorable as possible to the develop- ment of these organisms and to secure their most efficient action. The manner in which the disintegration and decomposition of sewage is accomplished by bacteria is given by Woodhead as follows : " The first process is the result of the activity of organisms that are capable of taking up their oxygen from the ak, and, second, those the result of the activity of organisms that so break up and re -arrange the organic molecules con- taining oxygen that not only do the bacteria themselves take up oxygen, but they allow of its being handed on to the products to which in their process of metabolism they give rise. It is probable that here we have to do not only with nascent oxygen, but with certain products set free during the process of decomposition, which seize upon oxygen with very great avidity. This decomposition or re-arrangement is spoken of as a process of nitrification or a conversion of the nitrogenous elements into ammonia, nitrous and nitric acids, carbonic acid, and water." It would appear that the destruction of organic matter buried in the soil takes place apart from any process of putrefaction, and the action is more rapid near the surface of cultivated ground where the soil is porous and readily permeable to both air and water. Here are found, in vast numbers, the micro-organisms of the aSrobic class. As the organic matter is washed down deeper into the soil it is seized upon by the anaerobic class of microbes, which, imable from their situation to obtain free oxygen, have developed the power of acquiring it from other substances which are broken down by them into simpler forms. Below a certain depth, bacteria are absent. Woodhead found this to be about twelve feet, but the number of micro-organisms present is very limited before this depth is reached, depending upon the nature of the soil, its moisture, porosity, temperature and the amount of organic matter usually present on the surface. Antiseptics and a consid- erable degree of heat at once arrest these chemical changes. A knowledge of these facts pertaining to the life-history of the nitrifying bacteria throws light upon a number of important sanitary points — as with reference to the disintegration of faecal matter in earth-closets ; the necessity for the inter- mittent in place of the continuous discharge of sewage where the latter is disposed of by irrigation ; or the reason why polluted water, which escapes from a drain or cess-pool at a point below that where bacterial life can maintain an existence, will, in certain soils, infect water to a considerable distance and depth, while foul liquids placed on the surface of the soil would be cleared of impurities at the depth of a few inches. 584 THEORY AInTD PRACTICE OF MILITARY HYGIENE. The practical application of the above facts to the purification of sew- age is made by a number of methods depending on the same general laws. By nearly all of these processes a clear, bright effluent is obtained, almost inodorous, while oxidation of all organic matter, both in suspension and solution, is secured. Provided that suitable conditions are observed E-:--iS& 'E Fig.. 301.— Plan ol Scott-Moncrieff Apparatus. for the establishment and cultivation of the specific micro-organisms con- cerned, there is almost no limit to the degree of purity capable of attain- ment with regard to sewage. It also appears that if the filteriag apparatus be given periods of rest, its efficiency can be maintained indefinitely. Among the various forms of apparatus, that of Scott-Moncrieff is very satisfactory. This is a filterrag-tank filled up to the level of the overflows with small bits of flint, upon the surfaces of which the organisms are prop- agated. An iron grating supports this cultivating material and allows the sewage to escape upward from the entering channel underneath. The action in this filter is chiefly anaerobic ; the effect being to bring the solid sewage into a state of solution and into a condition of instability which renders it eminently susceptible to further changes. The latter, largely in the line of a conversion of the soluble sewage into ammonia and nitrates, is brought about by the action of the aerobic bacteria in a second portion of the apparatus. This consists of a nitrifying chamber containing a number of sieves or trays, supported one above the other on a metal framework. Into the uppermost of these trays the effluent from the first tank is con- ducted through metal troughs, which are balanced so as to tilt when full and discharge their contents, automatically regaining theii- original posi- Fiii. 303. — Soott-Moncriefl Cultivating Tank. Section E.E. tion. The liquid thus discharged into the top tray percolates into those below, occupying about seven minutes for its complete passage. Each tray is filled with small fragments of coke to a depth of six inches.. An air space is provided between each of the trays so as to render the germs cul- tivated on them thoroughly aerobic. Since the liquefaction of sludge is naturally a much slower process than the purification of the already liquid portion of the sewage, a longer period of operation is required in the first step of the process. The longer the sewage remains in the first filter-tank DISPOSAL OF EXCEETA, SEWAGE AND REFUSE. 585 the greater the reduction in the opacity of the effluent. With respect to the secondary or nitrifying filter, it should be understood that the latter in its highest stage of biological efficiency wUl effect only a given percentage reduction of the pollution of its affluent. Thus if a pollution be high and the filter capable of effecting a purification of fifty per cent., its effluent will still remain a filthy Liquid, and must have its contamination still further re- duced by passage through another aerobic filter. These filters are sometimes suddenly and unaccount- fig. 303. - scott - Moncneff ably overtaxed— a condition noted by a high elimi- ?"#'™"°«^ '""'"'■ ^"^ nation of ammonia — when the sewage must be passed into another nitrifying apparatus and the first filter given a rest. Mouras' " vidangeuse automatique " is an early type of the so-caUed septic-tank system, being an au-tight box through which sewage is passed and in which the anaerobic microbes are propagated. In Cameron's modifi- cation of this apparatus in use at Exeter, in England, in a tank having a ca- pacity of 1 6 1 , gallons about 90,000 gallons of sewage are dealt with daily. The sewage entering the tank is coarsely screened to arrest any foreign ob- jects which may have gained entrance. The inlets to a small chamber, just outside the tank proper, are placed close to the bottom, and being larger than the outlets into the septic-tank, the sewage enters the chambers under a certain amount of pressure, thereby agitating any sediment and enabling it to separate from the organic matter present. From this chamber, the sewage flows over a submerged weir which divides the former from the septic -tank. The tank itself is deprived of light and air as much as possi- ble ; the sewage remains almost stationary in it for some Kttle time, event- ually escaping from an outlet at about the middle depth. Under such conditions, the anaerobic microbes multiply with such great rapidity as soon to dominate the situation, and were it not for the entrance of fresh material would soon be destroyed by their own products. Through a window in the center of the tank may be seen a layer of floating scum containing the lighter solids, and at the bottom a thin layer of heavier sediment. The greater part of the organic matter of the floating substance being dissolved, the residue falls to the bottom, but here it is apparently seized upon by bacteria and a bubble of gas is formed which buoys it again to the top ; here the gas escapes and the particle of solid sewage again falls and the process is repeated while any organic matter remains. The contents of the tank are in constant movement from the bubbles of gas and the particles ascending and descending. The residue resulting from this treatment con- sists of inorganic ash upon which the microbes cannot feed. This residue is small ; two million gallons of sewage passing through a tank twenty- fom- feet by nine feet leaving only four inches of sediment, while a liquid effluent of a brownish-yellow tint was the result. Upon leaving the septic- tank, the liquid sewage has a slight odor; but this is soon lost by aeration in overflowing the sides of a V-shaped trough through which it passes on the way to the nitrifying filters. These are five in number, two being in alternate use and one at rest; it having been foimd that each filter should have a rest one week in four. From these filters, which contain coke, breeze and clinkers to a depth of five feet, it is possible to obtain from an origin- 586 THEOEY AND PRACTICE OF MILITARY HYGIENE. ally foul sewage a perfectly clear filtrate containing a fifth of organic ni- trogen per 100,000 parts, which is less than the amount suggested as admis- sible for Great Britain by the Elvers Pollution Committee. From what has been said, it is evident that this simple and inex- pensive method of sewage disposal would be specially applicable to military posts, under conditions where the discharge of unpurified sewage iato streams, or its use on sewage-farms, would not be practicable. Precipitation. — The precipitation of sewage in tanks, by natural sedi- mentation and by precipitation with various chemical substances, is carried out in some large cities. The liquid thus clarified is allowed to flow over land or filter through it, though sometimes it is passed directly into streams. The sludge is removed from the settling-tanks at frequent iatervals. Lime, lime and aluminum sulphate, lime and protosulphate of iron, aluminum sulphate with blood, clay and carbon are all substances or combiuations of substances which have been employed. These form bulky precipitates which entangle and carry down all suspended matter. The effluent water after precipitation is merely clarified sewage, and it would undoubtedly be unsafe to use water from a stream which had received such partially purified sewage higher up in its course. In vi„w of the cost of artificial precipitation of sewage and the far better methods for its purification, chemical precipita- tion possesses no advantages for the military service. Disposal of Garbage and Eefuse. The maintenance of posts in a sanitary condition, as with all other collections of habitations, depends upon the proper disposal of filth of all sorts — among which, next to the excreta, that of garbage is of the greatest sanitary importance. The proper collection and removal of this material has already been discussed in connection with the sanitation of standing camps, and the subject requires no further consideration in this connection save in respect to the manner of ultimate disposal. In the German army, all garbage is carefully collected in large covered barrels and sold, the purchaser removing the same twice daily. This arrangement, however, is frequently impracticable in our army, and is nearly always undesirable. Frequently the garbage has been thrown on a dumping-groimd in the vicin- ity of the post ; ground near the inhabited area usually being selected from convenience, and the accumulation of years ultimately becoming so exten- sive as to be a reproach and a nuisance. Ashes and cinders may be used on roads or for filling, and if not required for this purpose their deposit ou a general dump is not injurious. Stable manure may sometimes be used for the fertilization of post gardens, while the excreta are generally disposed of by water-carriage. Nevertheless there is always much solid waste at every post which is best destroyed by fire, and for the accomplishment of this a crematory of suitable size should always be available. Particularly where the military reservation is small and is surrounded by civil com- munities it is imperative that the waste should be destroyed by such ap- paratus. Of late years, efficient crematories have been constructed at a number of posts, among them being Forts Leavenworth, Sheridan, Mc- Pherson and Sam Houston. One built at Columbus Barracks proved to be inefficient and fell into disuse. A crematory constructed at Fort Co- DISPOSAL OF EXCRETA, SEWAGE AND REFUSE. 587 lumbus in 1885, and rebuilt six years later, consists of a fire-brick cham- ber divided into three spaces by iron gratings which support the garbage and refuse. A taU chimney gives a powerful draft and combustion is ex- cellent. There is no offensive odor and the smoke is scarcely perceptible, iu spite of the fact that no special arrangements were provided for con- suming the products of combustion. At present, a number of types of STACK ELEVATJON SECTION AT A-A SECTION AT B-B FRONT ELEVATION Fig. 304.— Recent Model of Crematory for Post Use. crematory are in use in our service. The most generally satisfactory model is the one shown in the accompanying Olustration ; crematories af- ter this plan having been recently constructed at a number of posts in this coimtry and in the tropics. In this apparatus, the heat from the burning garbage and refuse, after the combustion of this is once started, is of much value in drying and destroying subsequent charges of waste material. The destruction of excreta by fire is accomplished only at stations where the Smith crematory, described in connection with the sanitation of camps, is in use. CHAPTER XIII. THE PEESONAL CLEANLINESS OF THE SOLDIER. The maintenance of personal cleanliaess is even more essential in the military service than under the ordinary conditions of civil life ; to some de- gree on account of the arduous duties often required of the soldier, with their concomitants of dirt and sweat, but particularly because of the military necessity of living in common. The importance of proper bodily cleanliness, however, was long unrecognized and in. former times the barrack-yard pump, with bucket or hand-basin, afforded the only facilities available for the performance of his ablutions by the soldier. Under such conditions it is evident that no very extensive toilet could be accomplished; a daily washing of the hands and face, with an occasional foot-bath, being about all that could be attempted in inclement or wintry weather. Until a com- paratively recent period, cold baths in sea or river afforded the only facilities for the attainment of general bodily cleanliness among troops of all countries ; a condition of affairs which obviously left much to be desired with respect to the physical purity of the soldier. Baudens, in referring to the former lack of personal cleanliness among the French troops, says of the forces at the Crimea : " On a review day our soldiers presented, by their new and well-brushed uniforms, an irreproachable military aspect; but these fine battalions left, as they passed, the weU-known stench of the barracks." Not until about the beginning of the present generation was any provision officially made in the military service for the cleansing of the person ; the soldier himself being duly educated in the belief tbat diligence in the brushing of the uniform and polishing of the equipment amply replaced such a supposedly unimportant deficiency. Bathing of the entire body, ex- cept in summer, was thus rarely performed ; if actually carried out, it was accompanied by so many discomforts and difficulties as to be not soon re- peated. In this respect, the conditions existing in the United States service during the past will scarcely bear close scrutiny. The general installation of bathing facilities among our military posts dates from a period barely fif- teen years gone by, while even within the last five or six years the arrange- ments for the attainment of bodily cleanliness by the soldier, at a number of posts, have been of a most insufficient and primitive character. For such a condition of affairs the medical staff is in nowise responsible ; sanitary reports for many years teeming with references to the deplorable lack of bathing facilities existing in various army stations. The fault is entirely that of officers of high rank in the line and of officials of the supply department; indifference and lack of initiative being, in theii- case, euphoniously desig- nated as conservatism. In this respect, however, the United States army has not alone suffered. So late as 1856, the Eoyal Commission investi- THE PERSONAL CLEANLINESS OF THE SOLDIER. 589 gating the conditions existing in the British army found that, up to that time, no arrangements whatever for bathing were provided in the military establishment ; the soldiers being forced habitually to employ for the wash- ing of their feet and persons such tubs as were used in barracks for the reception of the urine voided during the night. In the French cavalry service a system was until recently in operation — if indeed it is not even now in use in Algeria — by which the heat produced in the fermentation of stable manure was utilized for the warming of water employed for bathing purposes. Barrels containing the water were buried in the decomposing compost heaps ; the water, under ordinary conditions, attaining a temper- ature of 28°-30° C. in twenty-four hours ; 40°-45° C. in forty-eight hours and 66°-70° C. after six days. In the same service, also, the bath-houses have often been located in close proximity to the hospitals to permit of warm water being drawn from that source — the fact that the hospitals may, and frequently do, contain cases of a contagious nature apparently receiving no consideration where an economy of fuel is concerned. Of late, how- ever, a marked change for the better, in this respect, has occurred in the military services of nearly all nations; the importance of bodily cleanli- ness, as affecting the health and efficiency of the soldier, has been generally recognized and adequate provision made for its maintenance. It is evidently impossible to determine exactly the influence which the provision of better facilities for the maintenance of cleanliness among troops has had upon military morbidity and mortality, since improvement in this respect has been accompanied by changes for the better in other en- vironmental conditions which also powerfully affect the well-being and efficiency of the soldier. In 1886, when substantially improved arrange- ments for the cleansing of the person of the soldier were being introduced into a number of military posts, the constant non-effective on account of disease, in the United States army, was 41 per 1,000 strength. For the following decade (1886-1895) the non-effective was'31.62, while in 1897 it was 26.73 — a decrease of 34.81 per cent. It is only fair to presume that this reduction depended, at least in part, upon the greater attention given to the personal hygiene of the soldier. During the war with Spain, of the several volunteer regiments encamped at Augusta, Ga., a marked difference was noted in their respective sick -rates. The reason for this difference was reported by the medical officer attached to the regiment pre- senting the least sickness, and possessing at the time the only bathing facilities, as follows: "While we are not prepared to say that the lower sick-rate is due entirely to the use of this bath-house, yet we believe that the perfect system of bathing in this regiment plays no smaU. part in its decreased sick-rate." In the French service, it was noticed by Haro that the general installation of adequate bathing facilities resulted in a consider- able diminution of affections of the skin among the troops. Cavalrymen, on account of the nature of their duties, must usually pay closer attention to the cleanliness of the person than would be neces- sary for foot troops — but every soldier, when in garrison, should be required to wash the face, head, neck and feet once daily, cleanse the hands prior to each meal and bathe the entire body at least as often as once in five days. In addition, a frequent toilet of the genitalia is of advantage ; since it renders the soldier attentive to the first manifestations of venereal dis- 590 THEORY AND PEACTICE OF MILITAEY HYGIENE. ease, prevents possible multiplication of the pediculus pubis, and enables young soldiers to escape that scrotal pruritus by which they are so often inconvenienced, particularly in hot weather. The cleanliness of the person and garments of the soldier should be a constant object of solicitude on the part of his superiors, while the taking of general baths should be made a matter of official record. In the armies of Great Britain, France, Germany and other countries, the soldiers are regularly inspected by medical officers, at short intervals, to ensure due cleanliness of their persons and clothing as well as for the early recognition of cases of existing contagious or venereal disease. It is much to be re- gretted that a similar custom has not been officially instituted in our own service and that the feeUngs of the individual are treated as of more im- portance than the general welfare. It would be of advantage if at least once a week a careful inspection of the persons and apparel of the men could be made; the neck, breast, arms, feet and legs being bared for the purpose. Lavatories. — These should be readily accessible from squad-rooms, al- though not in direct connection with them, to enable men while partially clad to reach them without danger of chilling. Lavatories wholly de- tached from barracks, while preferable in warm countries, are undesirable in cold climates; since frequent sudden transitions from heat and cold, without proper measures for protection on the part of those exposed, are often provocative of sickness. The best arrangement under such condi- tions consists in connecting a small outbuilding, devoted to toilet purposes, with the company barrack — the connection being made by a covered pas- sage provided with lateral doors and windows to permit of transverse ventilation by perflation. The floor of the lavatory should be well drained and of a material impervious to moisture, while all parts of the apparatus or plumbing should be readily accessible for purposes of cleanliness. The room itself should be large, sunny, well ventilated and sufficiently warmed, since to perform his ablutions properly the soldier must uncover his neck, arms and the upper portion of his chest; an action he wOI not take unless the room be free from chiUiag air-ciurents and is maintained at a comfort- FiG. 305.— Plan In Section of Sunken Bowl Lavatory Fixture. able temperature. Lavatories should be so arranged, connected and con- ducted as to render the maintenance of personal cleanliness by the soldier a valued privilege rather than an irksome task. In the United States military service there are nearly as many varie- ties i]Q lavatory equipment as there are garrisoned posts. Of late, how- ever, two general plans have been selected for future use ; one consisting of a number of sunken bowls supported in a solid metallic frame, while the other is merely a broad, shallow trough fm-nished with removable THE PERSONAL CLEANLINESS OF THE SOLDIER. 591 granite-ware hand basins. The trough plan appears to be preferable ; since, according to Bertrand, wash-bowls, when used in common, may serve as agents for the propagation for contagious disease. For the better mainte- nance of their cleanliness, also, lavatory basins should be movable rather than fixed. In the French service neither basins nor washstands are pro- vided, but the soldier is expected to perform the daily ablution of face, neck and hands with a small jet of water, turned on as required. The faucets are placed at intervals of thirty centimeters along the waU and are so Fig. 306.— Lavatory Trough, as Used in tbe United States Army. constructed as to yield a sufficient flow without wastage. They discharge into an open trough raised to a height of forty -five centimeters above the floor, the trough being intended for use in washing the feet. The plan seems to be not without considerable advantage, as affording ready facili- ties for the cleansing of the feet without the necessity of a general bath. In our army, no proportion is officially required to be maintained be- tween the number of men to be accommodated in barracks and the number of lavatory basins to be supplied for their use; but company lavatories, as at present being constructed, contain ten or twelve hand-basins. This number is ample for the needs of a peace strength of sixty men to the company, but is evidently not sufficient for the full war strength of double that number. A minimum proportion of one basin to each eight men should be required. In the British military service the of&cial allowance is twelve hand-basins to each one hundred men, but in addition four foot-baths are also provided. In the British and some other foreign armies, warm water is not sup- plied to lavatories even during cold weather. The use of such tempered water, however, is always advisable, both on account of the increased comfort afforded troops and the more ready cleanliness obtained by its use. Each soldier should be required constantly to possess, for his indi- vidual use, a piece of soap of good quality and one or more clean towels. The use of toilet articles in common should be strictly forbidden. Towels in particular, if used in this manner, may readily transmit many conta- gious affections, notably purulent conjunctivitis — a disease formerly so prevalent in armies as to be known as "military ophthalmia." Baths and Bathing. — Bathing of the person, when properly per- formed, is cleansing, exhilarating and enjoyable. The application of water to the surface of the body not only removes epithelial debris, dirt, grease and perspiration, but it also stimulates the cutaneous functions and 592 THEOEY AND PEACTICE OF MILITARY HYGIENE. acts as a tonic to the system as a whole. Since the pores of the skin are only partially self-cleansiag, in the absence of bathiag a certain amount of cutaneous irritation must naturally result and the elimination of an ia- creased amount of effete material is thrown upon the kidneys. The bath should preferably be taken in the morning and bathing at night' is gener- ally to be avoided. A general bath should not be taken within two hours immediately following a meal, or while the individual is perspiring or is exhausted by fatigue. There is less danger ia the application of cold water to the surface when perspiring, however, than there is ia exposing the person, iu a partially nude condition, to chLUing by evaporation. In taking cold baths of any kind, the muscles should be kept in constant action and the head should first be wet; the latter to prevent the too great increase of encephalic blood-pressure which may accompany a gradual im- mersion from the lower extremities upward. Cold baths taken immedi- ately after exercise but after the cessation of perspiration, if not too pro- longed and if followed by vigorous friction of the surface, largely relieve fatigue and give a sense of exhilaration. Chilliness, with numbness of the extremities, is a warning to discontinue a bath ; the body, after bath- ing, should be thoroughly dried by brisk rubbing with a coarse towel. This stimulates the cutaneous circulation and prevents chilling through evapo- ration of the surface moisture ; it also removes the greater liability to chafing and eczematous eruption where the skin is subjected to friction by cloth- ing. Soft water is preferable for bathing purposes, since it prevents or reduces cutaneous irritation as well as being more cleansing in its action and economical of soap. In France, the rain-bath system has been officially adopted in the mih- tary service, each soldier being required to bathe the entire person at least once every seven days. The same system is employed in the German army ; the douche playing for two periods of one and one-half minutes each and using 15-20 liters of water for each individual — ^weekly baths being required. The shower-bath system is also in use to some extent m the armies of Austria and Belgium, although in the former country there are no official requirements as to the frequency of bathing. Steam vapor baths are used in the Eussian army and by the troops of Roumania. In Eussia, the military barracks are not usually provided with bathing facilities and the men are sent to the public bathing establishments in the vicinity. In the camp at KrasnoS-Selo each soldier is requhed to take a vapor bath once in eight days. Tub baths are still used in Holland; the soldier of the Dutch service being required to bathe the entire person once weekly, half an hour being allowed for the procedure. In the Japanese army each sol- dier is required to bathe daily in summer and thrice weekly in wmter, tubs being used for the purpose. Tub-bathing is also largely employed as yet by the British troops on the home stations. At various English bar- racks, notably those at Chelsea, the bath-room is located in close proximity to the kitchen. The tubs are supplied with cold water only, and the in- dividual bathers are required to procure from the kitchen tanks such hot water as may be necessary. Such an arrangement is clearly unsatisfactory. In the army of the United States, the tub-bath system was alone employed prior to 1898, when shower baths were installed in several military posts; regulations simply providing that the soldier shall "bathe frequently." . THE PERSONAL CLEANLINESS OF THE SOLDIER. 593 In the military service, swimming, already discussed in connection with the physical training of troops, is indulged in at the present time for pur- poses of instruction, exercise and pastime rather than for bodUy cleanli- ness, except during field service. As favoring physical purity as well as for other reasons, it should, however, be encouraged imder all suitable circum- stances. Troops should be prohibited from bathing in bodies of water which have been contaminated with sewage, since the cause of neither health nor cleanliness is advanced under such conditions. If the matter be left to their own discretion, soldiers wiU not hesitate to bathe in almost any water, no matter how great its foulness. Surf-bathing, besides its cleans- ing properties, has a particularly tonic effect, together with an additional cutaneous stimulation due to the sea salt. The use of vapor baths in the United States military establishment, as is customary in the Russian army, is wholly inadvisable ; on account of their increased cost and the greater time necessary for their accomplish- ment, and also because the method is neither popular nor well known in this country. Tub baths, still in use in several armies, are mentioned only to be condemned. They should have no place in the military service. They are expensive, inconvenient and unsanitary, and are not practicable for use for the bathing of a large number of men in a short period of time. Tub baths, while possessed of many grave disadvantages, have no desirable qualities which are not shared in even greater degree by rain baths. The rain or shower bath has every important advantage when com- pared with the tub bath or immersion system. The first cost of the ap- paratus is considerably less, while the subsequent outlay for operation and repairs is also reduced. The fixtures are of the simplest character and there are no parts liable to injury even with ignorant or rough usage. Re- pairs, if needed, can never be of a costly nature. The rain bath is cleanly and economical in management where a large number are being bathed, since it is always in readiness for immediate use and requires little at- tendance — while the bather is assured of an ample supply of constantly clean water. No time is lost in the filling or emptying of tubs, and the necessary cleansing of the latter, after use, is entirely avoided. The rain bath also requires less time for its application while even more efficient in cleansing the bather, and hence more baths can be administered in the same space of time. Exposure to its action for five minutes is ample for aU purposes of cleanliness — a duration of only three minutes being con- sidered as sufficient ia the French and German services. The apparatus occupies much less floor space than a proportionate number of tubs, and thus more bathers can be accommodated at the same time in a given area. In the rain bath, also, the body of the bather does not remain in contact with soiled water, the waste at once flowing down from the person and escaping through the outlet, while in the tub bath the individual is constantly im- mersed in a solution of his own ehminatory products. Thus Edel has cal- culated that the average number of microbes given off by the person of the adult human being during a bath, based on the hypothesis that the individ- ual bathes once daily, amounts to 3,860,000,000. Among the micro-organ- isms so given off, the bacillus coU communis was invariably found by him to be present. A bath by immersion, particularly if the water be very 38 694 THEORY AND PRACTICE OF MILITARY HYGIENE. warm, has often a debilitating effect and fails to refresh the bather — whereas the descending fine stream of the rain bath acts both as a general tonic and a powerful stimulus to the circulation. According to Edge- combe, the effect of immersion in cold water is to raise the arterial and lower the venous pressure through peripheral constriction. Cold Bath — Two Minutes at 13° C. Pulse rate. Arterial Pressure (MM. HG.). Venous pressure J Maximum. Minimum. (MM. Hg.) Before . . 70 73 190 310 130 150 25 After 10 If to the effect of cold that of percussion is added, in the form of a strong rain douche applied simultaneously to the whole surface of the body, the arterial pressure becomes raised to a greater extent th,an with cold alone, while cardiac action is increased. In a strong shower bath begun at 37° C. and rapidly cooled down to 16° C, extending over a period of two minutes, the following results were obtained : Pulse rate. Arterial Pressure (MM. HG.). Venous pressure Maximum. Minimum. Before 64 73 115 150 85 115 15 ji^fter 10 The effect of warm baths, on the other hand, is to reduce the arterial pressure to an extent roughly proportionate to the increase of temperature; but if the warm water be appHed as a douche, the elevation due to the percussion greatly overbalances the lowering effect of the temperature. It was found by Berblinger in a series of experiments carried out upon twenty-two medical officers of the Russian army that the average muscu- lar strength of the individuals observed rose from 108|^|- kilograms before a cold shower bath to ll?^^ kilograms fifteen minutes after the bath; and was still 115^ kilograms at the end of half an hour. An important advantage of the rain bath for the military service is that it requires much less water to achieve the same results ; fifteen per cent, of the water used in an ordinary immersion bath suiScing for an ample shower bath. The danger of communicating skin or other diseases by means of infected fixtures is, with the rain-bath system, of course en- tirely avoided. In usiDg the shower bath, warm or tepid water is more efficacious from the standpoint of cleanliness. The nozzle should be turned so that the spray is projected obliquely against the body ; thus avoiding the disagree- able sensation of suffocation which accompanies the impact of vertical spray upon the head. The bather should stand in a shallow tub or depres- sion in the floor of the cell, so that the soapy water, when washed from the person, may collect about the feet, soften the epidermis and facilitate cleansing. In addition to a descending shower, a movable spray or horizon- THE PEKSONAL CLEANLESTESS OF THE SOLDIEE. 695 tal jet may be advantageously provided for the better cleansing of the ax- illse, genitalia and perineal region. The warm bath should always be com- pleted with a cold shower, to contract the cutaneous capiUaries and better protect the individual against those forms of disease so largely favored by atmospheric conditions or changes. As is the case also with lavatory basins, there is no definite ratio in our service between the number of men present for duty and the amount of bath apparatus to be supplied. At present, in the plan of barracks now being erected, three shower baths and three or four tub baths are supplied to each company. In the British army only one bath tub is provided for each hundred men — a fact which, combined with the lack of heated water, results, according to Evatt, in the practical discontinuance of bathing by the British soldier between the middle of October and the middle of April. For a temperate climate one shower bath to each twenty soldiers should be the mini- mum ; a larger number of tub baths, if they are in use, being required. For sta- tions liable to have a fluctuating strength, as at recruiting stations, the bathing fa- cilities should be proportioned to the greatest authorized capacity of the bar- racks. This would avoid any such con- ditions as occurred at Columbus Barracks in 1898, when, owing to an influx of recruits, it was reported that, even with all the tubs in the bath-house in use night and day, it was impossible to se- cure a bath for each man as often as once a week. Rain-Bath Systems. — In its sim- plest form, the rain bath consists in a rose nozzle placed at an elevation of seven to ten feet, perforated by a large number of fine openings and supplied with a stream of tempered water slightly above blood heat. A primitive and economical bathing system which, ac- cording to Viry, is stiU. continued in certain of the French barracks, con- sists in heating water ia a large kettle on top of an ordinary stove. The warm water is then mixed with cold in proper proportions in a tank or tub and is raised by an ordinary hand pump to the sprinkling apparatus which serves to shower the men. In the United States military service two quite dissimilar forms of shower apparatus are in use — the Clow and the Schaffstaedt systems. The Clow shower bath, shown in the accompanying illustration, uses a mixture of hot and cold water, these being passed into a mixing tank before reaching the bather. The supply pipes are run along the upper portion of the wall in order to avoid the necessity of piercing the floor, with the resulting interference with efforts at cleanliness and ever-present possibility of leakage. This system, of an iaexpensive character, is being Fig. 307.— Clow Shower Bath, as Usea in the United States Army. 696 THEORY AND PEACTICE OF MILITARY HYGIENE. installed in all the army posts now in course of construction. To ensure the uniform and proper temperature of the water, and to avoid the waste of time which results when each soldier adjusts the tem- perature of his own bath, it would be well to supply all showers from a single boiler in which the contauied water is maiutaiued at a constant degree of heat. This is readily accomplished by the use of an internal steam coil, provided with an automatic valve, by Fig. 308.— Tank for Maintaining Warm Water at a Constant Temperature. which the supply of steam is cut off as soon as the water reaches a certain temperature. Such a tank requires an occasional cleansing if the water used be hard, a spe- cial opening at the end being provided for this purpose. The Schaffstaedt patent rain-bath apparatus is in use on various army transports and is also extensively employed in the German military and naval service. As the system requires the use of steam for heating pur- poses, its connection with an existing steam plant or the installation of a special boiler — not necessarily ex- pensive in character — is necessary. The working prin- ciple consists in causing water and steam to flow in opposite directions, but in such a manner that they do not mix. As is shown in the accompanying vertical section of the apparatus, the steam enters the tube in the body of the apparatus through the steam pipe h and the steam valve g, passing out at the lower end at c. The water enters at a, and rising past the descending steam is warmed by the latter. It then passes through the water valve/ and pipe d to the overhead douche e. The steam, descending noise- lessly, parts with all its heat and is discharged at the bot- tom of the apparatus con- densed into water, its tem- perature being about the same as that of the cold-water supply. By turning the han- dles / and g, the water and steam valves are opened to- gether, wide enough to secure the desired temperature of the water as indicated by the thermometer. The tem- perature can be regulated by the steam- valve g. no. 3io.-universai Mixing Valve. The Universal mixing valve is especially ap- Fio. 3U9.— Sectional View of Schaftstaedt Apparatus. THE PERSONAL CLEANLINESS OE THE SOLDIER. 597 plicable to the Schaffstaedt apparatus. With its use the turning on of hot water without at the same time estabhshing the flow of cold water is im- possible, even with handling by inexperienced persons, and hence the dan- ger of scalding is avoided by the bather. The capacity of the apparatus must be proportioned to the number of douches on each warm-water supply line and the water and steam press- FiG. 311.— Detail Showing Row ol Douclies Supplied from a Single Large Schaffstaedt Apparatus. ures should remain constant. In its use a non-commissioned ofBicer pref- erably operates the valve, determines the temperature of the water by ref- erence to the attached thermometer and controls the length of time during which the douches are in operation. At the end of the bath he gradually lowers the temperature of the water by slowly turning the handle of the steam valve, a procedure which does not affect the water pressure. This system is specially applicable to the transport service, siace steam of a certain pressure is always available and sea-water can readily be pumped up and heated by the apparatus for use for bathing pm:poses. Post Bath-Houses. — It is essential that bath-houses be kept neat, scrupulously clean and inviting in appearance, and that they be well heated, properly ventilated and am- ply lighted. While the better class of flooring for bath apartments is made of vitri- fied tiling, equally good results are given by floors of artificial stone, fin- FlG. 312.- F -Vertical Section of Basin In Bathing Cell with Shower-Bath System. 698 THEORY AND PEACTICE OF MILITAEY HYGIENE. ished off with cement. Asphalt is impervious to moisture and is said to be somewhat more agreeable to the feet of the bathers. The floor should be graded so as to be drained by one or more waste pipes. To afford better fa- cilities for cleansiag the feet, the flooring under each shower should be slightly depressed. The re- sulting basin, of several inches depth, may be moulded in con- crete and provided with a standing over-flow or with an adjustable strainer over the drain, so that the water does not escape quite as rapidly as it is delivered. The walls and partitions should be finished off with some non-absorbent material, such as enamel-faced brick or corrugated galvanized iron, painted with several coats of enamel paint. Partitions should be raised about twelve inches from the floor to facili- tate its cleansing and promote the circulation of air. The height of the dividing parti- tions should be not less than seven feet to ensure privacy. For bath cells, in the mili- tary service, no furnishing other than a perforated soap cup and a hinged seat should be provided. All plumbing should be durable, plain but substantial, and perfect from a sanitary standpoint. All waste pipes should be so pro- portioned as quickly to remove all soiled water. To prevent splashing and afford privacy, a small curtain of washable material may be hung up in the doorway of each compartment, but usuallythis is not desirable. The accompanying diagram shows the plan of a bath-house adapted to the military service, as used in the German army, and of ample size for the needs of a regiment. The room contains two rows of eight baths each, or sixteen bath apartments, centrally arranged. On each side wall there is a row of twenty-four seats, with overhead clothes-hooks, affording a total seating capacity of forty-eight. There are three times the number of seats that there are bathing cells. The latter are numbered and three ad- THE PERSONAL CLEANLINESS OE THE SOLDIEE. 599 joining seats are given the corresponding number. After the first sixteen men are undressed, they occupy the sixteen compartments and, while they bathe, the second squad of men occupies the second set of seats. When the first squad leaves the bath to dress, the second set takes its place iu the baths and the third detachment occupies the third set of seats and begins to imdress. When the second squad leaves the baths to dress, the third squad takes its place, the first squad leaves the bath-house and a fourth squad enters and prepares for bathing. It will be seen that such an arrangement permits of the rapid bathing of a large number of soldiers. The capacity of such an establishment, provided three squads are bathed per hour, is 480 baths per day of ten hours. The size of the bath- ing hall is about 25 X 50 feet, but may be modified to suit local condi- tions. The level of the corridors is slightly raised to prevent their wetting when baths are being taken. If the floor of each cell is not depressed to form a basin, it should slope so as to discharge into a common gutter, with Fig. 314.— Ground Plan of the Shower-Bath System as Used In the French Army. A, Water heater ; B, dis- tributing Apparatus ; C, tubs ; V, drain. perforated cover. It would seem necessary that such a bath-house should be provided with a urinal, to avoid the possible perpetration of nuisances by the men while bathing; In the German army the lavatories and baths are in separate builduigs detached from the sleeping quarters. This plan is excellent and should be followed in our own service. It is true that detached lavatories, bath-houses and latrines are in use in some of our garrisons, as illustrated in the preced- ing chapter, but their employment should be extended to all posts and under aU conditions. To put plumbing of any sort in a barrack building is a mistake ; and where a lavatory and bath-room are in the basement of a bar- rack, this basement is necessarily damp and close. It is by attention to such minor details that the sick-rate can be lowered in the future. The Care of the Person in the Field, — The results of uncleanli- ness during campaign have been graphically portrayed by Smart, as fol- lows : " Nor was positive disease lacking as a consequence, for the irrita- tion of the skin caused by the heat, perspiration and the contact with dirty underclothing, hardened by moisture, organic elimination and epithelial 600 THEORY AND PRACTICE OF MILITARY HYGIENE. debris from within and dust and all manner of uncleanliness from without, led to papillary uiflammation, accepted ia its milder form as 'prickly heat,' but which, in cases aggravated by the nails of the iudividual and the browsing of pediculus corporis, became erythematous, eczematous and finally formed a special disease known as camp eczema or camp itch. The amount of suffering and loss of sleep from various degrees of this con- dition did much to impair efficiency, irrespective of loss from men ab- solutely driven to hospital for relief. The disgust with which persons of cleanly habits regarded themselves and their neighbors, when more or less affected in this way, was often productive of low spirits and home-sick- ness." The maintenance of personal cleanliness in the field depends to a large extent upon the energy and desires of the soldier, for much may be done in the way of cleansing the body even with meagre facilities. During active service, every possible attention should be given to cleanliness of the body, and marching troops should be required daily to bathe the. arms, genitalia and feet in the prevention of chaf- ing, balanitis, pruritus and excoriations. Cold swimming-baths, in river, lake or sea, serve an excellent purpose as regards clean- liness, and their use should be favored when- ever time, place, circumstances and season permit. It should not be forgotten, how- ever, that severe chills may follow inuner- sion in cold water by such individuals as may be suffering from malarial infection. If the supply of running water available for bathing is small, a hole may be dug in the bed of the stream and allowed to fiU, or a small dam may be constructed. Sponge baths are always available and are of great value during campaigns. They are best taken by spreading the rubber blanket over a broad, shallow excavation in the ground and thus forming an improvised bath-tub. The contents of two or three canteens of water poured into this rubber tub suffice for the attain- ment of excellent results as regards cleanliness, while a wet cloth admir- ably takes the place of the sponge. Where actual bathing or washing of the person is not practicable during field service, the body should be rubbed, morning and night, with a damp towel. Some soldiers habitually wash themselves thoroughly after arrival at camp at night, contenting themselves with scanty ablutions before beginning the day's march. It is well to re- member, in this connection, that the use of strongly alkaline water, partic- ularly when associated with exposure to the dust of the march and the rays of the sun, has a marked effect in producing roughness and soreness of the skin and cracking of the lips. Habits of carelessness as to personal cleanliness, of a more or less permanent character, may be induced through the lack of facilities for washing and bathing during a long campaign, and such are of course to be opposed in every way. Fig. 315.— Tabasco Water-Heater. THE PEESONAL CLEANLDSTESS OF THE SOLDIER. 601 Fig. 316.— Diagram Showing Simple Ar- rangement for Obtaining a Hoi^Water Supply in Camps. In summer camps, when the ablutions can be performed in the open air, excellent arrangements for a lavatory and for shower baths, in the presence of a piped water-supply, can rapidly and economically be made ; such arrangements well repaying the slight labor and expense involved by the increased comfort thus afforded troops. In winter, however, both shelter and warmth must be provided, and it is evident that in tempo- rary camps during cold weather the bathing of the entire person can rarely be properly accomplished — particularly since the water-supply imder such circumstances is usually scanty, or, if sufficient, there is lack of means properly to utnize it. In winter quarters, during the Civil War, a hot-water supply was often extemporized by fitting a camp kettle with circulation pipes con- nected with pork barrels, the warm water being drawn off from the latter as required. The Tabasco water-heater is simple in con- struction, easy of manipulation and mod- erate in cost. The average size is capable of heating 300 gallons of water per hour. Where obtainable, it would serve an excellent purpose in connection with the camp bath-house. In camps of a semi-permanent character, an early and imperative duty consists in the erection of suitable structures for use as wash and bath- houses, equipped with facili- ties for the supply of a limited amount of hot as well as an abundance of cold water and with proper provision for the removal of all waste. Wher- ever a piped supply of water has been laid, rough buildings, containing a number of stalls for shower baths sufficient to meet the needs of a regiment, can he constructed at a cost of about $200 each. The water may be heated by passing it through a coil of pipe built into a brick fireplace, cold water being admitted into the main channel through another pipe. The floor, constructed of ce- ment, should drain into a tem- porary sewer, or, if no better arrangement be possible, into a stoned or ce- mented gutter discharging into a covered and ventilated cesspool located at some distance. For a bath-house in winter quarters, the plan suggested by Billings some years since, for use at frontier posts, serves excellently. Fig 317.— Ground Plan of Bathing Cells as Proposed by Bil- lings. 602 THEOEY AND PKACTICE OF MILITARY HYGIENE. In this plan a series of bathing cells (C, D, E, etc.) surrounds a central space, containing a stove and hot-water tank (L) and separated from it by a latticed partition to admit of the reception of heat. One cell (K) is left incomplete to allow of entrance to the stove. The cell floors slope down- ward and inward one inch to a common drain. The dimensions proposed were as follows : The central space to be 5 ft. in diameter ; the bath cells. 4 ft. 6 in. deep, 5 ft. 3 ia. across widest end, and 6 ft. in the clear; door- ways to be 2 ft. wide and 6 ft. 6 in. high. For of&cers in the field, an excellent arrangement for securing shower- baths consists in carrying in the equipment a small rose-nozzle, such as is- commonly supplied with modem bath-tubs, to which is attached several feet of rubber pipe of small caliber. A bucket of water of the proper tem- perature having been secured, the rubber pipe has a stone or weight at- tached to its free end and the whole is immersed in the water. It is then pinched at both ends, while the rose nozzle is carried over the rim to fall below the level of the water in the bucket. Siphonage at once begins, and the bucket may be hauled up to a sufficient height by a bit of tent-rope or halter-strap passed over the ridge-pole of the tent or a con- venient bough. The rubber blanket is stretched beneath the bucket over a shallow exca- vation, as already suggested ia connection with the sponge bath. Outside the bucket, which can generally be obtained ia camps where there is any wheeled transportation, the necessary apparatus does not weigh more than three or four oimces in all. The Care of the Feet. — The care of the feet has been to some extent discussed in connection with the conduction of the march ; the maintenance of cleanliness being of the greatest importance in ensuring their integ- rity during campaign. The skin of the feet is particularly rich in sudo- riparous glands and is subject to abundant exfoliation of the epidermis. The fetid secretions, confined by the coverings of the foot, soften the cuti- cle and render it, in the absence of proper cleanliness, more sensitive to pressure and friction. Particularly in warm weather is the lack of proper attention to the feet a source of cutaneous irritation. The application of water does not make the skin tender, but on the contrary hardens it, and, by promoting local nutrition, assists in preventing the occurrence of blis- ters, corns and callosities. Cleanliness of the feet of the men is a matter to which company officers should give their careful attention ; a daily foot-bath being under aU circum- stances desirable, in garrison as well as on the march. Proper facilities for foot-baths should always be available in connection with the company wash-room ; if not officially provided, they should be improvised. Men should be instructed to cut the toe nails squarely across, not rounded and not too far behind the end of the toe. Removal of the corners has a strong Fig. 318.— Bathing Cells Proposed by Billings, in Vertical Section. THE PERSONAL CLEANLINESS OF THE SOLDIER. 603 tendency to promote ingrowth of the nail, particularly with too narrow shoes. Hard corns, if painful, may be shaved down with a sharp knife or scraped with a piece of broken glass. Soft corns, between the toes, should receive several applications of a saturated solution of salicylic acid in col- lodion ; when, after soaking in hot water, the corn can be readily extracted en masse. The same procedure is also effective with respect to hard corns. It has recently been proposed to require the company barber to look after the feet of the men in his organization, after a preliminary course of instruction by the medical officer. This is an innovation which would undoubtedly be productive of good results if its details were prop- erly carried out. At present, the care of the feet receives too little consid- eration in our service. Great attention is paid ia the German army to this matter, and it is required that the feet of each man shall be inspected by one of his company officers, a medical officer and the Lazarethgehiilfe — corresponding to our hospital steward — at least twice a week in barracks and oftener in active field manoeuvers. The method of making this inspec- tion is to form the companies in squads, standing upon tables or benches sufficiently high to briag_ the feet directly under the eye of the inspecting officer and to bring under his observation any wincing or flinching when the inspected man jumps to the ground barefooted. The inspecting officer passes down the line, carefully examining the front of the feet and legs, which are bared to the knees, searching for strained tendons, blisters, im- properly cut nails or untrimmed corns. Having passed down the line, the men are about-faced and the tendines A c hilli s carefully examined ; and the soles are inspected as they raise one foot and then the other. As a man passes from the table or bench, he leaps to the ground and runs to his shoes and stockings. This is to show any bruised soles or periostitis of the tarsus. Any case of blisters, improperly cut nails or tendo-synovitis are at once cared for by the Lazarethgehillfe. More serious disorders are sent to quarters or hospital. At the same inspection each man's socks or " fuss-lappen " and boots are carefully examined as to their condition of cleanliness. As the German infantry regiments average in marching a kilometer in ten minutes, being often pressed to a kilometer in from seven and one-half to eight minutes, each man carrying sixty pounds, this care of the feet is most necessary. When tables or benches are not available, the trunk of a fallen tree or a block of stone is made use of for the foot inspection. The Care of the Mouth. — Broken or carious teeth considerably im- pair the efficiency of the soldier. Besides exposing him to the liability of odontalgia, alveolar abscess and periostitis, the possession of such teeth implies an impairment of the powers of mastication which, with the use of the hard ration of the field, may often induce intestinal disturbances and diarrhoea. Soldiers who are affected with foul or diseased mouths are an- noying, if not actually dangerous, to their comrades; their fetid breath being a powerful factor in the pollution of the atmosphere, of the tent or squad-room, whUe the saKva of such cases has been shown to contain an unusual proportion of pathogenic bacteria. Dental caries is much more common in certain races or localities than in others. Among our negro troops, even when no care whatever of the mouth is taken, the teeth are often observed to be clean and sound, without tartar or decay. 604 THEOEY AND PEACTICE OF MILITARY HYGIENE. Ulcerative stomatitis has been common ia armies, frequently becoming epidemic, although much rarer of late years. While this condition is un- doubtedly to be regarded as primarily of scorbutic origia, the proper clean- liness of the mouth and care of the teeth may do much to prevent its oc- currence or modify its severity. Carious teeth should be promptly filled ; both for their own preserva- tion and to avoid the favoring of decay in their soimd neighbors through contiguity. It would be much to the, advantage of the service if dentists were provided by the Government to care for the teeth of men while in the field or at isolated stations. Tooth-brushes should be furnished by the Government as part of the equipment of the soldier, and their proper use in all instances required. In the absence of such official action, it becomes the duty of company officers to insist upon their purchase and regular em- ployment by those under their command. Usually the men themselves, especially the better ckss of soldiers, pay much attention to the care of the teeth, and it is undoubtedly the case that in ouj service the hygiene of the mouth receives far more consideration than is given it in foreign armies. Among our soldiers it is those of ahen birth who are the most derelict in this respect ; but careful oversight of the habits of all recruits is necessary. Tooth-brushes should be used twice daily. They should be made of soft bristles and are not to be forcibly employed, as tending to render the teeth sensitive through mechanical retraction of the gums. The motion of brushing should always be in the direction of the teeth and never across their surface. In the German army, a weak solution of salicyKc acid is to some extent employed as a tooth-wash, but for application to the teeth powdered chalk best answers all purposes. Wood ashes and wood char- coal make an excellent dentifrice and are frequently employed by soldiers for this purpose. The Care of the Hair and Beard. — The hair of the soldier should always be kept short; not only to permit of the more ready cleansing of the scalp but to lessen the liability of infection by insect vermin and con- tagious skin disease. Long hair is the glory of a woman but the shame of a soldier. Wolseley recommends that the hair never be permitted to exceed half an iach in length during campaign, or be at any time so long that the soldier is enabled to part it. The head should be particularly well cared for whUe in the field,' and should when possible receive a daily washing with soap and water. Brushiag of the hair should be done at least once daily, and preferably prior to each meal. For greater uniformity of appearance as well as for purposes of cleanli- ness, the wearing of the full beard is not desirable ia the military service. Although during campaign the growth of full beards is often a matter of necessity, under such conditions they should be kept closely cropped by the use of scissors or clippers. In the army of the United States there is at the present time no restriction as to the growth of hair upon the face, provided that the beard, if worn, shall be neatly trimmed; but up to the outbreak of the Civil War a regulation was in force prohibiting the wearing of hair on the face of the soldier below the angle of the jaw. In the British military service, the Highland regiments are allowed to wear the full beard ; while the flowing moustache was, in that service, long the dis- THE PEESONAL CLEANLINESS OF THE SOLDIEE. 605 tinguishing mark of the cavalryman. The Eussian soldier is authorized to wear the full beard ; but in the French army only the moustache or the so-called imperial can be worn. An extensive epidemic of sycosis or "barbers' itch " occurred at Madison Barracks in 1898, the infection following the use of uncleanly razors and shaving brushes. It is well known that ringworm, favus, certain eczematous eruptions, seborrhoea, syphilis and other diseases may also Jdc readily trans- mitted through the agency of the company barber ; his instruments usu- ally serving as the means through which the infection is accomplished. Hence all barbers in the military service, before being authorized to ply their trade among troops, should receive instruction from a medical officer in the general hygiene of the hair, beard and skin, and should thoroughly understand the technique required in the sterilization of brushes and instruments. Permission to continue the practice of their calling should depend upon the maintenance of scrupulous cleanliness, both of the hands and instruments ; while they should be required to refuse to serve and report at once to the medical officer such cases of possibly contagious skin affection as may come imder their observation. Greases or emollient preparations of inferior quality and injurious properties should not be em- ployed. The disinfection of shaving-mugs, scissors, clippers, razors and brushes may be accomplished by chemical solutions or boiling water. Heat damages the temper of razors, hence they are best disinfected after each use by immersion in a solution of tricresol, of one per cent, strength, for five minutes. Brushes may be cleansed by the use of water of ammonia or borax in solution. They are, in practice, preferably disinfected by immer-' sion in a 1—1,000 solution of mercuric chloride. Such hair-brushes as have inadvertently been employed on cases of tinea, favus or similar dis- ease should, however, be preferably destroyed by fire. Powder-puffs and similar articles, such as cannot be treated with aqueous solutions without injury, may be disinfected by the use of absolute alcohol. The applica- tion in common of alum or magnesia, in solid form, should be prohibited. When used, they should be applied with a clean towel in the form of a fine powder. After finishing with a customer, the hands of the barber should be carefully washed and aU bits of hair should be collected and destroyed, preferably by fire. Insect Parasites. — Destruction of head or body Kce, a simple matter in camp or garrison, often becomes a difficult problem during active cam- paign. If the head becomes infested, the hair should be closely trimmed and receive frequent and thorough shampooing, followed by the washing of the scalp with a 1-2,000 solution of mercuric chloride. This solution should contain a small amount of vinegar to loosen the nits from the hair. In the absence of opportunity for the accomplishment of the above treatment, care- ful use of the fine-tooth comb gives good results. On prolonged campaigns it may fairly be questioned whether such a comb should not form part of the personal equipment of the soldier. While mineral oil is an efficient parasiti- cide, its use in the hair for such a purpose is not advisable ; since a number of cases have occurred in which its application to the scalp, accompanied by friction, has resulted in apparent spontaneous combustion and fatal burns. According to WoodhuU, infested clothing may be freed from insect ver- min by soaking it in a barrel of water containing a handful of " fish ber- 606 THEORY AND PRACTICE OE MILITARY HYGIENE. ries " (Cocculus indicus). Sabadilla powder, dusted freely along the seams of garments, will destroy the pediculus vestimentorum ; but its use must be frequently repeated, as it has no effect in preventing the hatching of the eggs of the parasite. The powdered seeds of the stavesacre (Delphi- nium staphisagria) have long been used for the destruction of Kce. During the Civil War, iufested clothiag was commonly turned inside out and the seams were carefully gone over by hand for the destruction of lurking insect life. To prevent a return to this favorite retreat, the inside seams were sub- sequently greased with blue ointment or with the ointment of the nitrate of mercury. The destruction of the "nits," as well as of the body lice themselves, may be speedily accomplished by the thorough boiling of the infested garments, preferably in soap-suds or weak soda solution. BoOiag water, however, is with difficulty obtained in the field for other than cook- ing purposes, and hence the destruction of vermin by this method is only rarely practicable during active campaign. In garrison or where a steam sterilizer is available, the use of this agent is followed by satisfactory re- sults, save in respect to the resulting shrinkage of woolen garments. Men of the most careful and cleanly habits are liable to infection with body lice through inadvertent and often unavoidable contact, and the in- fested person of a single slovenly individual may be the means of the introduction of annoying parasites throughout an entire command. The early detection of such vermin, with prompt application of measures look- ing to their destruction, is of the greatest importance in the prevention of their dissemination among troops. Infection with the pediculus pubis, or crab-louse, is not usually brought about or favored by military conditions. A daily toilet of the genitalia win do much to prevent the continued existence and multiplication of this parasite. The remedy is shaving of the parts with the application of mer- curial ointment, together with proper measures directed to the clothing of the individual affected. During the Civil War, parasitic skin diseases were extremely common and assumed an unusually severe character; 32,080 cases being diagnosed as "itch," while 35,667 cases were merely recorded as "skin disease." The pathology of the affection known as " army itch " was much disputed at the time, but sulphur, sulphide of lime, kerosene oil, and similar reme- dies of' known value in the treatment of scabies appeared to have been successful in bringing about its termination. At the present time, scabies is far less prevalent among our troops than in those of the various Euro- pean powers. The average annual number of cases of scabies occurring in the United States army, for the decade 1885-1894, was 21.1; but there has been great improvement in this respect in recent years. In 1895 there were 12 cases of this affection, in 1896 there were 10 cases, while in 1897 only a single case was reported — showing the practical re- sults of the greater attention latterly paid to personal cleanliness in our military service. Cleanliness of the Clothing. — The washing of the clothing of the enlisted man in the United States army is left entirely to the discretion of the individual and is not under any direct military control. At pres- ent, such persons as may do the washing for troops have no official status ; but company laundresses, in the proportion of four to each organization. THE PERSONAL CLEANLINESS OE THE SOLDIER. 607 were formerly officially recognized in the military establishment, were paid for their services and were given allowances in the matter of rations, quar- ters and fuel. These laundresses were appointed by the company com- manders, and were usually, though not necessarily, the wives of enlisted men belonging to the organisation to which they were attached. The system was preferable from a sanitary standpoint to that now in use, since it placed the washing and laundrying of clothing under the immediate control and ready supervision of the military authorities. The act of Congress approved June 18, 1878, prohibiting women from accompanying troops as laundresses, and the subsequent restrictions placed upon the enlistment and re-enlistment of married men by army regulations and orders, practically did away with army laundresses and compelled the enlisted men to do their own washing or have it done outside the post. This seems inconvenient and unsatisfactory ; and the introduction of duck clothing and linen collars adds to the expense, especially in southern latitudes. Some amelioration seems due the men in the active service of the Government, and the establishment of post laundries would solve a troublesome problem and prove a strong ally to contentment, cleanliness and appearance; and seems to call for special consideration, since the habitual method of doing laundry work in the tropics, in running streams and without boiHng, increases the danger of certain cutaneous diseases. Where the laundry work is done in the present haphazard fashion, more- over, a soldier can plead the neglect of an irresponsible washerwoman as an excuse for his dirty linen and underclothing. The soldier is nominally at liberty to wash his own apparel should he so elect; but as a matter of fact, adequate facilities for the laundryiag of clothing are not provided ia barracks and he is perforce compelled to patronize such individuals, resident in or in the vicinity of the post, as can advantageously carry on such work; the usual monthly charge for this service being one dollar per man. At Jefferson Barracks a large steam-laundry plant, under control of the Quarternjaster's Department, was long in operation and in every way yielded eminently satisfactory results. It was, however, unfortunately destroyed by fire several years since and has never been re-established. Such steam laundries, for hygienic reasons as well as for convenience and economy, should be installed at aU posts garrisoned "by sufficient troops to ensure the payment of their running expenses. It is obvious that hygienic precautions can be more carefully maintained in a large central laundry establishment than where soiled garments are scattered at frequent periods among a large number of insanitary households, in which they are often improperly cleansed and are frequently themselves exposed to the danger of infection with the elements of disease. Where steam laundries conducted by the Government would not be practicable, there is no reason why a large central laundry should not be established in each garrison and conducted under the management of the post exchange. The services of the women at present performing the work of laundresses could be hired by the new establishment ; and thus aU soiled articles could be thoroughly and promptly cleansed, under sanitary condi- tions and at a minimum of cost to the soldier. In European armies, the barracks are supplied with an equipment of laundry apparatus ; since the soldiers, by reason of their meagre pay, are 608 THEORY AND PRACTICE OF MILITARY HYGIENE. necessarily forced to wash a considerable proportion of their own apparel. Laundresses, in the proportion of two to each battalion, were long included in the organization of the French army, but at present, in that service, the washing of soiled clothing is done by contract and at the expense of the Government. Each company receives a monthly sum for this pur- pose, amounting to about ten cents for each soldier — but provision is made for the laundrying of only a limited number of articles and the excess must be washed by the man himself or be done at his expense. In time of war, the laundrying of clothing for troops cannot be properly performed by the people among whom the war is waged, and hence during campaign each soldier must wash his own clothing. As the proper per- formance of the operation is something of an art, troops should have prac- tical experience, prior to campaign, in the methods in which it is best accomplished in the field. Soiled body linen, when impregnated with sweat and dust, is irritant to the skin, favors the invasion and multiplica- tion of insect parasites and emits mephitic odors — hence frequent oppor- tunities for the purification of such articles wUl conduce greatly to the health, comfort and efficiency of troops in camp or on the march. Filthy surroundings or ^garments may readily neutralize all efforts for the main- tenance of bodily cleanliness. Blankets, as well as underclothing, should be washed at suitable intervals — a matter intimately related to the cleanliness of the soldier, yet one too often neglected. It occasionally happens that through inattention on the part of company officers to the personal cleanliness of their men, their underclothing is worn until it attains a most filthy condition. Bodily cleanliness cannot be maintained under such conditions even if a daily bath be taken, and vermin can usu- ally be traced to some such source. The facilities for the laundrying of clothing in the field are usually of a most primitive character. Artillerymen frequently employ for this pur- pose the canvas horse-buckets available in that branch of the service, while a rubber blanket placed over a shallow hole in the ground, as already noted in connection with bathing, answers equally well. A stray barrel, partially filled with soap-suds, can be excellently utilised ; clothing washed therein being secured to a rope and allowed to float in a rimning stream, if one be available, for several 'hours. The clothing should, whenever possible, be immersed in cold water for several hours before washing to soak out all soluble impurities. Water so employed is highly charged with organic matter and micro-organisms ; Miquel estimating that each cubic centimeter of such water contained, on an average, 26,000,000 bacteria, where ordi- nary sewage contained only 6,000,000. It is obvious that such water should never find its way into a source of supply, nor should it be thrown upon the ground in the vicinity of camps. Boiling, from the hygienic standpoint the essential part of the operation of washing, is necessarily omitted during campaign. After the preliminary soaking, the garments are soaped, rubbed, rinsed and hung up or spread on bushes to dry. Woolen articles, to prevent shrinkage, should be washed in cold water without the use of much soap or of unnecessary manipulation and should be dried without wringing. In the absence of washing, woolen clothing may be cleansed by drymg in the air and sunlight, followed by a thorough shaking and beating. Changes of clothing, treated in this manner, should THE PERSONAL CLEANLINESS OF THE SOLDIER. 609 be worn on alternate days. The results given by this method are second only to those of actual washing. In the washing of clothing a certain proportion of soap is said to be with advantage replaced by petroleum. This method is habitually prac- tised in the armies of Eussia and Germany, and has recently been adopted in various military hospitals throughout Europe. It is claimed for the process that cleansing is rendered easier, clothing suffers less deterioration and is made much whiter. The usual proportion employed in foreign armies is one gram of mineral oil for each liter of soapsuds used. The washing of clothing becomes a much more simple problem if the camp be located upon a water-course ; in which instance a special place should be set aside for laundry purposes, below the sources of water used for cooking and for the watering of animals. In time of epidemics, es- pecially of cholera or typhoid fever, the washing of clothing in the field becomes a particularly serious sanitary problem, since even a small stream may transport infectious micro-organisms over a long distance and induce outbreaks of disease in villages far down its course. In conclusion, it may be remarked that the maintenance of cleanliness of the person and apparel of the soldier demands constant watchfulness on the part of company officers. Individuals of careless or slovenly habits are usually recruits, and if among old sojdiers they will generally be forced by the latter to take measures looking to proper cleanliness of body and rai- ment. While soldiers are, as a rule, quick to appreciate the value of cleanli- ness of the person and clothing, and to take prompt advantage of such op- portunities as are afforded for its attainment, it is advisable that company officers frequently satisfy themselves by personal observation as to the proper condition of the more indolent. As expressed by Woodhull, "it is not sufficient to see that the arms are bright, the clothing spotless, or the bedding neatly rolled. Dirt that is hurtful is not the mud of the highway or field, nor the dust of the parade caught on the outside of the shoes and clothing; it is the cutaneous debris, mingled with dust and dissolved in perspiration, soaked into the underclothing, organic dirt that offends the nose as well as the eye, that depresses the subject and may poison his comrade." 39 CHAPTER XIV. MILITAEY MOETALITY AND MOEBIDITY. Broadly speaking, the main causes affecting the health of troops are the manner of living, the environment and the food supplied. The first relates to the occurrence of overcrowding, imperfect ventilation, want of cleanUness and inattention to personal hygiene. The second is typified in the accidents arising from atmospheric or telluric influences, such as rapid death from heat and cold, the comparatively transient influences of the seasons and the slower and more durable effects of climate as modify- ing diseases of a restricted habitat. The last cause concerns the diseases brought about directly or indirectly by vicious aliiyentation. Beside these, other influences of a less apparent but scarcely less potent character oper- ate to affect the health, and consequently the efficiency, of armies. These act as predisposing rather than exciting causes of disease, and have special relation to the vital resistance of the soldier as affected by race, age, length and character of service, the fatigue and hardships of campaign and other factors. Some of these predisposing causes, in fact several of the most important of them, can readily be removed and thus prevented from con- tributing so materially to military inefficiency. With respect to others, sanitary science possesses no means for their elimination or avoidance and can at best merely endeavor to modify their effects ; but since no precau- tionary measures are capable of entirely neutralizing their results, they must be considered as more or less inevitable in their character. Operat- ing insidiously as these various predisposing factors do, they have not re- ceived in the past the consideration which their importance warrants, and a study of their influence upon the rates for sickness and death among troops is well worthy of the attention of the military sanitarian. These latter points it is the purpose of the present chapter to discuss. Army Medical Statistics. — For a better understanding of the fol- lowing subject matter, a brief consideration of army medical statistics, considered both as a whole and separately, is of importance. Their pur- pose is to define the influence of military life upon health, and to permit the ready appreciation and accurate comparison of varying conditions of service and environment in their relation to the well-being of the soldier ; hence a knowledge of their composition is important to the sanitary officer. Since each case of sickness in the mUitary establishment at once becomes a matter of official record at the hands of competent observers, it follows that statistics so obtained are not only more comprehensive but more accu- rate than those bearing on the occurrence of disease among civilians. Unfortunately for their general utility, however, they are based upon a physically superior class, always existing imder restricted and unusual conditions and frequently in unfavorable surroundings, and hence deduc- tions which may be drawn from them cannot be legitimately applied out- MILITAEY MORTALITY AND MORBIDITY. 611 side the limits of the military service. Unfortunately also, owing to the different systems of nomenclature and classification of diseases which have prevailed in the past, as well as to other causes which wiU be referred to later, it is not always possible accurately to compare the sickness and mortality from special causes occurring in different armies, or even for the military establishment and civilian classes of the same nation. The com- mittee on international military medical statistics which met at Budapest in 1894 has, however, formulated a plan which overcomes in great meas- ure the difficulties with which army statisticians have had to contend, leads to a common basis of comparison and wiU ultimately be the means of affording a large amount of information hitherto not available. In the British army, statistics with regard to sickness and mortality were first compiled shortly after the close of the Peninsular war, but were published at long and irregular intervals. They gave much information with regard to the healthfulness of various stations, but the advent of the Crimean war caused their temporary discontinuance. In 1859 their pub- Kcation was again resumed and they have since been issued annually. Army statistics have been collected in France and Germany since the Napoleonic wars, but have not been regularly made available for general use ; frequently being issued only in part or not at all. Of late years, France has not given out full information as to the occurrence of disease and death among her military forces. Elaborate statistical reports with respect to the health of troops are now published by Austria, Eussia, Bel- gium, Italy and other foreign countries. In the United States army, satis- factory data for the period prior to 1840 are not available, and it is only since 1884 that figures sufficiently elaborate to be of any great value to the statistician have been compiled and published. At present, the official returns show not only the amount of loss the army annually incurs from various forms of disease, but also the causes leading thereto; as influenced by race, age, length of service, arm of service, season, station and other factors. Little information is gained by recording the statistics of disease as a whole ; since so many factors combine in the production of the final result that these must be studied separately to arrive at a proper understanding of the significance of the latter. The main points upon which army medical statistics are based are as follows : 1. The number of admissions to sick report as compared with the number of persons furnishing the sick. This is accomplished by taking the actual numbers in both classes and reducing them to a comparable standard in rates per thousand. The numbers furnishing the sick are ob- viously reduced by those sick in quarters or hospital ; but as a general rule an equivalent number of men are returned to duty or are enlisted to replace the losses through death or disability. In our service, statistics are based on the total strength. 2. The rate of deaths per thousand strength. This is obtained by the division of the total number of deaths occurring during the year by the mean annual strength, including the absent as well as those serving with the colors. The figures thus obtained are then reduced to rates per thou- sand. 612 THEOEY AND PEACTICE OF MILITARY HYGIENE. 3. The rate of discharges for disability from disease, per thousand strength — obtained by dividing the losses from discharge by the mean strength and then reduciag to the above standard of comparison. 4. The total losses from disease, per thousand strength; as determined by the sum of the rates for mortality and for discharge for disability from this cause. 5. The rate of constant sickness, or constant inefficiency. This is given by addiug the numbers put down as remaining under treatment at the end of each day, week or month and dividing by the number of days, weeks or months in the period desired, again reduciag to the comparable standard. 6. The number of days of service lost by each soldier. This is found by adding together the total number of sick days furnished by a command during a given period and dividing the result by the mean strength of the comimand for that period. In all computations the figures are reduced to common terms of one year and one thousand strength. Comparative Loss in Campaign from Sickness and Wounds. — Since the great military epidemics of antiquity — the destruction of the Assyrians under Sennacherib; the plague described as occurring during the Peloponnesian war; the pestilences which ravaged the Eoman and Carthaginian armies; the great losses sustained by the army of Severus in the marshes of Caledonia — it has been established as a general rule that, in protracted wars, armies suffer much less from wounds and deaths incurred in action than from disease ; a fact which conclusively shows the necessity for a proper knowledge of military hygiene. The constant advance in sanitation, however, based upon a more accurate knowledge of etiological factors, has exerted a marked effect in duninishiag military morbidity and mortality ; and while in the future comparatively high rates for sick- ness and death among troops engaged in war are always to be expected, it is scarcely possible that such disastrous epidemics as have prevailed in times gone by could be repeated in the future. Further, wars become shorter as they become, through modern refinements, more expensive ; and troops, particularly in an aggressive and decisive campaign, are not now exposed to unhealthful influences to as great a degree as was the case when hostilities w^re more protracted. With improvement in the effec- tiveness of arms, both as regards range and rapidity of action, the pro- portion of casualty for any period of action must naturally be increased — and hence there is a constant tendency toward the approximation of the rates from wounds and disease. From the records of the past, however, many valuable lessons can stiU be drawn. In 1809, during the Walcheren expedition, the mortality in the British army from disease was 346.9 per thousand effectives, while only 16.7 per thousand were killed by the enemy. A few years later the British army in Spain lost three times as many men by disease as by the result of conflict, and the sick rate mounted to such proportions that more than twice the number of men composing the army passed through the hospitals during the year. In the Eussian campaign against Turkey, in 1828, it was estimated that 80,000 men died of disease and 20,000 in consequence of wounds. During General Scott's campaign in Mexico the MILITAEY MOETALITY AND MORBIDITY. 613 losses from disease alone exceeded 33 per cent, of the effective strength of the forces under his command ; and of a single regiment of Indiana volun- teers, which entered the service 1,000 strong, only 400 returned to the State for muster out. Laveran states that in the Crimean War the allies lost 52,000 men in six months, of which number 50,000 men were un- harmed by the Eussians ; while during the entire war, according to Viry, the French lost, in round numbers, out of a total force of 300,900 men, no less than 95,000, of whom 75,000 died of disease and only 20,000 died on the field or succumbed to wounds. In this campaign nearly one-fourth of the French medical officers are said to have perished from disease. During the war in Italy, in 1859, a period of hostilities of only short duration, there were, from the French force of 200,000 men, 129,950 ad- missions to hospital. In the war carried on by France in Mexico the mortality from gunshot and that from sickness was in the proportion of 10 to 29. The mortality among the United States forces in the Civil War was divided as follows : MortaUty. White. Colored. Total. Killed in battle 42,724 47,914 ;i57,004 23,347 1,514 1,817 29,213 837 44,238 49,731 186 216 Died of wounds Died of disease 24,184 Total 270,989 33,380 304,369 From the most reliable data available, the deaths in the armies of the Confederate States during this struggle did not fall short of 200,000, three- fourths of which number were due to disease and one-foiuth to the casual- ties of battle. In 1866, in the war against Austria, out of a total strength of 437,260, the Prussians lost in an unusually brief and decisive campaign 6,427 men by sickness and 4,450 at the hands of the enemy. The Franco-German war, in 1870-71, furnishes the only exception to the general rule that more men are killed by disease than by the weapons of the enemy, since of the German army 33.7 per thousand strength fell ia battle, while only 18.6 per thousand died of disease. This admirable result was largely due to the proper observance of sanitary precautions; assisted, no doubt, by the brevity of the campaign, the rapidity of the movements and the fact that active operations were conducted during the most healthful season of the year. In the Eusso-Turkish war of 1878, according to Viry, the Eussians lost 102,799 men, of whom only 16,578 were killed by the enemy. During the Spanish-American war of 1898, for the five months which included the total period of hostilities, of the 274,717 officers and men enrolled in the United States forces, there were only 345 men killed by the enemy while 2,565 succumbed to disease. For the whole year of 1898 the deaths from wounds in our service gave a rate of 0.62 per thou- sand strength, the killed in battle amounted to 2.79 per thousand strength, while the deaths from all causes aggregated 30.31 per thousand. Even in July, the month in which aggressive operations against Santiago were 614 THEOEY AND PEACTICE OF MILITARY HYGIENE. conducted, the killed in action amounted to only 1.25 per thousand, while the deaths from disease were 1.78 per thousand. An interesting side-light on the later results of hard campaigning is given by Eosse, in his statement that of the old soldiers carried on the United States pension rolls those disabled by disease are more than four times greater in number than those pensioned for wounds. Death Rates in Civil and Military Life. — The difficulties attend- ing an accurate comparison of death rates for the military service and those of civil life are necessarily very great. Owing to the rejection of intend- ing recruits, many individuals are at once retmned to private life whose early demise would otherwise have gone to swell the military death rate. ' Further, the army is maintained as a select body of physically sound men, and its weaklings are constantly undergoing elimination from the service ultimately to increase the mortality of civO. life. Hence the civilian rates are unduly increased, while army statistics fail to show all the deaths presumably due to mUitary service — and it is obvious that the more rigor- ously the standard for the soldier is maintained as regards physical excel- lence, the more favorable the showing apparently made for a military life. Vallin, in France, in 1871, placed the probable error due to the above causes at as much as 9.19 per thousand, thus practically doubling the figures for the military death rate of his time. Viry considered this allow- ance to be too high, but believed that a rate of 3.60 per thousand for such as leave the colors with incurable disease should be added to the military and subtracted from the civilian death rates ; thus making a difference of 7.20 per thousand. The later estimates of Marvaud placed the probable error at 4 per thousand. WTiile it is probably correct for the French ser- vice to add 3.60 or even 4 per thousand to the military death rate, to de- duct the same number from the civilian rate involves the broad assumption that the numbers in each class exactly correspond. For our own service, the immense disproportion existing between the present small army of 65,000 men and the large number of males of the military age living in the United States renders the influence of the comparatively small number of soldiers who may be discharged for incurable disease, upon the civilian death rate, of so little importance that it may practically be disregarded. The census returns for 1880 give the annual death rate for disease as 6.97 per thousand for all males between the ages of twenty and forty-five years. During the same year the mortality from disease in the United States army was 5.88 per thousand — apparently a distinct advantage in favor of the military service. If, however, Viry's factor, above mentioned, be accepted as correct for our service, the true mortality dependent on military service becomes 9.48, or 2.51 per thousand in excess of the civilian rate for the same period. As it is probable that since that time the death rate in the military service has diminished in proportionately greater degree than has been the case in civU life, it may be fairly assimied that, under conditions of peace, the death rate in our army is at present but slightly in excess of the mortality for the same class in civil life. The results obtained by Farr in his comparison of the death rate in the British army with the corre- sponding classes of civil life, made a generation ago, are as follows : Age,— 20-35— Soldiers 17.0 death rate per 1,000. Civilians 8.4 " " MILITARY MORTALITY AND MORBIDITY. 615 Age — 25-30— Soldiers 18.3 death rate per 1,300. Civilians 9.2 " " 30-35— Soldiers 18.4 " " Civilians 10.2 " " 35^0— Soldiers 19.2 Civilians 11.6 " According to Notter and Firth, the present death rate of the civil male population in England, at the soldier's age, is as follows : Age.— 20-25 5.4 mortality per 1,000. 25-35 7.4 35^5 12.8 Between the ages of 20 and 34, according to these authorities, the mortality is m favor of the soldier, but after 35 the mortality is reversed and the civil rates are lower. For the British service the death rate for the home stations was 3.42 per thousand ia 1897 and 4.68 per thousand for the decade 1887-1896. If the civilian death rate for all males of the military age be accepted as about 7 per thousand, the showing made compares favorably with similar figures for the German army and is superior to the French mortality rates. This is certainly a great improvement over the conditions existing in 1856, when it was shown that the mortality in the army at large was twice as great as among the civilian population, and in the case of the Foot Guards three times as great. As regards the German army, it was recently stated by its surgeon- general that during the early part of this century the death rate of the male civil population of Prussia, between 20 and 30 years of age, was lower than that of the military death rate, the figures being 14 per thou- sand for the army and 10 per thousand for the civil population. This condition is now reversed, and in 1893 the death rate in Prussia for the civil male population from 20 to 30 years of age was 6.38 per thousand, while at the same time the mortality for the German army was 3.00 per thousand. While these results are certainly admirable and are undoubt- edly in large part due to careful observance of sanitary regulations, it should be remembered that soldiers unable to maintain the required physi- cal standard are probably more thoroughly eliminated in the German ser- vice, and at an earlier period in their military training, than in other armies. In the French army, on the home stations, the average annual death rate from 1882 to 1890, inclusive, was 7.88 per thousand strength; while Bertillon fixed the annual mortality among the civilian male population, between the ages of 20 and 25, at 10.60 per thousand. Marvaud, how- ever, believed that the estimate made by Bertillon was too low, and placed the annual death rate for civilians of the military age at 12 per thousand. Using Marvaud' s coefficient of error, given above, the corrected rate for the French military service would become 11.88, while it would be 8 per thousand for the same class in civil Hfe. Marvaud concludes, with refer- ence to this subject, "that, in spite of all ameliorations which have been introduced, chiefly of late years, into the hygienic surroundings of the French soldier, his mortality rate is stiU. elevated and certainly exceeds that of the same sex and age in civil Hfe." 616 THEOEY AND PEACTICE OF MILITARY HYGIENE. Loss of Time from Sickness. — In the United States service the annual average number of days lost per man, for the decade 1886-1895, was 14.64. For the year 1896 it was 12.43 artd in 1897 it was 13.08. In comparing the number of days lost by white soldiers with those lost by colored troops, the showing is slightly in favor of the latter. For the entire British army, during the decade 1887—1896, the number of days lost per man was 21.38, while during 1897 it was 22.72. Among the British troops at the home stations the number of sick days per man did not differ very greatly from those of our own army for the same periods, being only a fraction of one day in excess. According to Eosse, ui a state- ment of the morbidity of various armies issued about 1884, the lowest rates given were those of the Portuguese, Austro-Hungarian, Italian and German armies, the sick days of each man in the effective force being from 13 to 15 yearly among the troops of these nations, while in the French and English armies, prior to that date, the rate had been 16 to 17 annually. As compared with the time lost by the corresponding classes in civil life, Eosse noted that, for the period 1872 to 1892, the average annual number of days of sickness was 6 to 8 for each workiagman belonging to various mutual aid societies ; he fixing the general military morbidity for the same period at figures two and one-half times greater than those of the corresponding civil classes. According to Paget, the following rate of sickness, such as incapacitates for work, may be expected at different ages for males of the English working classes : At 20 years expect 4 days of sickness yearly; at 20-30 years expect 5 to 6 days of sickness yearly; at 45 years expect 7 days of sickness yearly. Marvaud states that, ia 1894, the French soldier lost 13 days annually — 9 in hospital and 4 in barracks — while his civilian compatriots of corresponding age lost on an average only about half that time; notwithstanding the fact that the hygienic surroundings in the mUitary service were much superior to those of civH life. While in time of war or active operations the existence of a high rate of inefficiency and the loss of a greater amount of time are to be antici- pated, such conditions, as compared with those of the corresponding classes of the male civil population, should not, theoretically, obtain in time of peace. Their actual existence under the latter condition is probably due to the fact that the workingman does not feel able to stop his daily task except for serious illness, while the soldier — ^whose pay and living are assured and whose medical attendance is gratuitous — is inclined to abuse his privileges, often endeavoring to get his name on sick report for the slightest indisposition, or none at aU, and to have it retained there for as long a period as possible; this being particularly attempted when any unusually irksome or disagreeable task is to be performed. That such, indeed, is the case is demonstrated by the fact that, according to Billiugs, it may be estimated that for every case of death there is an average of two years sickness in the civil community; while in the United States army, for the absolute number of deaths occurring and days of service lost dur- ing the year 1897, the proportion was such as to show a total of 3,867 days of sickness to each death reported. This gives a total of 10.6 years sickness for each death; a rate more than five times greater than that obtaining in civO. life and one which can be explained only by the above MILITARY MORTALITY AND MORBIDITY. 617 hypothesis. In view of the unfavorable showing made by military statis- tics in this respect, it would appear that greater discretion and severity should be exercised in admitting the soldier to sick report; and that, if once admitted, his earlier return to his duties would frequently be produc- tive of neither injury nor hardship.- Race as Influencing Military Mortality and Morbidity. — While satisfactory data on this subject as regards foreign armies are naturally not available, the several rates from disease in our own service, with its heterogeneous persoimel, have been calculated according to nativity. For the seven years 1890-1896, they were determined, per thousand strength, to be as follows : Aamlssions to hospital. Constantly non-effeetire. Discharges for disahliity. Deaths. Total losses. United States 1,043.43 962.05 810.10 907.11 1,033.14 886.08 853.38 893.75 807.14 836.93 1,049.43 821.42 30.74 26.87 24.67 23.56 32.81 26.55 25.64 27.82 21.63 26.21 30.89 33.90 12.98 14.53 13.20 12.46 18.87 13.83 12.50 13.81 16.53 13.33 10.56 13.66 3.96 5.46 4.14 4.26 4.16 5.17 1.47 2.90 2.67 5.55 7.04 3.86 16 94 Ireland 19 98 Germany 17 34 England Canada 16.73 33 03 Scandinavia 18 50 Scotland 13 97 Switzerland 15 11 Austria .^ 19 20 Denmark 18.88 France 17 60 All others 17 53 It should be noted, however, that the figures given for the countries named in the latter half of the above table are not to be regarded as absolute, since they are not based upon a sufficiently large number of men to avoid the possibility of error. These rates are, however, of particular interest since, so far as they go, they tend to bear out the popular belief that the native-born American possesses a greater proportion of vital force and greater power of resistance agaiast death than does the foreigner. Eace proclivity, as regards sickness, is well shown by the records of the British forces in the West Indies, in which, for the ten years 1879- 1888, the admissions per thousand of strength for white troops were 966.9, colored, 1,114.2; constantly non-efPective, whites 46.62, colored 62.35; deaths, whites 14.94, colored 14.81; discharges for disability, whites 13.57, colored 39.33. In the United States service, the much greater proportion of sickness and deaths occurring among the negro troops during the Civil War, as compared with white soldiers, is shown in the chart on page 619. For the decade 1877-1886, the death rate among the whites of our army was stiU much lower than among the colored troops ; the rates being 9.97 per thousand for the former and 12.91 for the latter. In 1888 the report of the surgeon-general called attention to the fact that the amount of sickness among the colored troops was greater than that among the white soldiers stationed in the same military departments. There has been, hawever, a constant tendency for the past twenty years toward the approximation of the rates for the whites and blacks in our ser- vice; and the relative rates per thousand for white troops as compared with those for the colored troops, during the year 1897, were as foUows: 618 THEOEY AND PRACTICE OF MILITARY HYGIENE. Admissions to hospital. Constantly non-effective. Discharges foraisabiUty. Deattis. Total losses. W^hites 35.73 37.24 11.04 10.89 9.63 9.51 5.05 5.89 14 67 15 40 Since 1897 the relative proportion of deaths, discharges and admis- sions to hospital has not differed to any extent among the white and colored troops. In the distribution of diseases among white troops, according to nativ- ity, typhoid fever and rheumatic fever had their greatest prevalence in our service, for the years 1890-1896, among the Canadians and Scandiua- vians. The highest admission rates for consumption were 5.70 among the French and 4.76 among the Scotch; the lowest rates were 1.42 among the English and 1.49 among the Germans — ^the rate among the natives of the United States beiug 3.33. Pneumonia was more frequent among Cana- dians, 5.18, and Scotch, 4.76, than in men of other nativities. The rate for this disease among the natives of the United States was 3.90. Venereal disease prevailed more among men born in the United States and Canada than among the others, the admission rates for these two classes being 93.98 and 91.92 respectively; the Irish and Swiss had the lowest rates, 47.66 and 50.96. The Irish, however, had by far the largest relative number of cases of alcoholism, 90.96. The smallest rates for this cause were given by the Danes, 12.59, and Austrians, 19.00; the admission rate for the native-born American soldier having been 28.51 for this cause. Sickness and Death Rate as Affected by Season. — Military morbidity and mortality are to a certain extent influenced by seasonal changes ; varying according to the climatic conditions prevailing in each country or locality, by which the propagation of certain affections is either favored or retarded. In the French army the admissions to hospital for disease, in time of peace, reach the maximum of 57 or 58 in January and fall to the minimum of about 38 per thousand in September. In the Italian army, for the period 1872-1892, the greatest amount of sickness occurred in March and the least in November. In the United States service the late summer period is the most unhealthful, while the late fall and early winter give the least sickness as far as troops on the home stations are concerned. On analyzing the figures for the seasonal prevalence of disease as it existed during the decade 1888-1897, the monthly admission rate was usually high in January from influenza and bronchitic attacks. From this point it fell to a minimum in April, after which it rose, slowly during May and June and rapidly in July and August, to the maximum of the year. It remained high in September, but fell again during the last three months of the annual period. The wave of prevalence during the months of July, August and September was due to malarial diseases. Prior to the decade mentioned this autumnal wave was larger than in recent years, and there was frequently a slight prominence in the curve in May or June, corresponding with a sudden increase of cases of intermittent fever. For the year 1899 there is little to be learned from a study of this curve of prevalence, for the climatic and other influences which affected it MILITARY MORTALITY AND MORBIDITY. 619 were too complex to be considered from this point of view ; and even with troops on the home stations, differences are found which are evidently not 3S- a S8t3 fiifa due to climatic conditions in this coimtry but to previous service of the troops in other climates. The conditions of field service also materially alter the rates of seasonal prevalence as established for troops in garrison. 620 THEOEY AND PEACTICE OF MILITARY HYGIENE. Thus for the year 1898, when the army, if not entirely engaged in active military operations, was, after the month of March, stiU in the field and on a war footing, the monthly rates per thousand strength were as fol- lows : January. . February . March April May June July August. . . September October... November December. Admissions from disease. 68.11 59.68 65.75 65.12 80.90 68.35 150.15 254.61 271.79 200.48 186.06 312.63 Discharges from disease. 0.40 .40 .50 .95 .31 .39 .31 .41 .31 .79 1.11 1.14 Deaths from disease. 0.33 .18 .31 .24 .21 .36 1.81 6.14 4.73 2.06 1.07 .84 Total losses from disease. 0.73 .58 .71 1.19 .52 .65 2.12 6.55 5.08 3.85 3.18 1.98 Locality as Affecting Health. — This is clearly a subject which can be only generally considered, since the rates for each station will vary with the local conditions of climate, soil, water, environment, the charac- ter of the service upon which troops are employed and many other factors. Within the United States, for troops in the various military departments existing under conditions of peace, the following table shows the relative amount of sickness duriag the year 1897. Department. Missouri . Dakota. . . Platte.... Texas. . . . Colorado . California Columbia ■aSS ill 5.61 5.30 4.77 7.37 6.34 3.56 3.15 6.20 is? 5.85 6.91 9.55 4.59 7.38 13.93 6.30 10.38 a 03* Sal 17.80 16.78 38.17 23.37 5.27 73.45 24.40 86.56 ■2*5 fe S3 I If! II 83.40 86.06 109.54 119.67 100.38 115.81 66.40 75.47 3 a 387.28 157.36 85.28 96.61 69.88 110.07 41.81 37.25 10.38 11.13 12.70 10.43 9.51 10.31 11.81 11.94 s ■= 11.46 12.21 14.33 11.86 13.63 17.49 9.45 16.53 gp-g 1,260.04 1,188.89 975.33 1,294.41 1.533.14 1,374.05 818.60 788.44 Swg 35.83 36.25 33.93 36.99 39.65 35.66 26.33 25.65 From the above it is seen that the Department of California is the most healthful, with the Department of the Columbia and Dakota closely following. The Department of Texas has long been recognized as the most unhealthful military division within the limits of the United States. The statistics for the entire British army in time of peace are of par- ticular importance, covering as they do a large number of geographical divisions under diverse climatic conditions and enabling the making of accurate comparisons through the similar sanitary, military and adminis- trative conditions prevailing throughout the whole. The figures for that service, for the ten years 1887 to 1896, are given below. MILITARY MORTALITY A^D MORBIDITY. 621 Ratio Per 1,000 Stkbngth. European Troops. ->( i s if ■go ¥ ill 11 997.4 8.81 33.65 14.52 58.57 Days. 31.38 735.9 4.68 16.27 42.51 15.52 708.8 4.01 15.33 8.35 46.65 17.02 666.9 7.53 19.30 10,53 44.39 16.17 998.8 11.08 19.04 13.09 65.48 33.90 499.1 4.37 14.34 11.90 25.54 9.32 559.3 10.07 13.65 8.14 29.58 10.80 1,119,3 8.43 20.33 18.40 64.48 23.54 3,653.7 45.03 337.94 13.86 84.89 30.98 868.8 6.63 33.97 14.54 55.85 30.39 1,364.4 15.04 55,94 17.43 73.76 36.93 1,038.0 11.10 30.35 11.43 58.39 31.37 1,334.7 11.31 33.34 14.38 64.97 33.71 1,073.1 6.73 18.14 9.37 73.48 36.46 1,443.9 15.50 35.17 13.24 84.87 30.98 1,133.8 6.41 Troops at home and abroad. . United Kingdom Gibraltar ' Malta Egypt and Cyprus Canada Bermuda West Indies West Africa* South Africa and St. Helena. Mauritius Ceylon China Straits Settlements India On board ship Days. 31.47 21.04 24.01 24.35 33.93 18.68 19.31 31.08 11.68 33.48 19.37 30.69 17.91 24.68 21.45 * For eight years only, 1889 to 1896. It is readily seen that the total losses vary from the minimuin of 12.26 per thousand at Gibraltar to the maximum of 57.88 on the west coast of Africa ; while the death rate of troops at home is only about half that of the entire army. The discharges for disability ia the latter instance are slightly higher, while the constant non-effective is considerably lower, as is also the number of days lost by each soldier. The mortality among the European troops of the French army on for- eign service, per thousand strength, according to Gayet, is thus propor- tioned among the following stations : Algeria 11 to 13 Antilles 18 to 22 Senegal about 73 Reunion before the Madagascar expedition 38 to 80 Reunion after the Madagascar expedition 80 to 90 New Caledonia 9 to 10 Cochin China 23 to 34 Tonkin about 75 While thoroughly satisfactory statistics with regard to our own troops at tropical stations are not as yet available, owing to the somewhat unsettled conditions as yet existing, particularly in the Philippines, figures for the regular and volunteer forces for the year 1899 are as foUows: Per 1,000 of Mean Strength. Cuba. Porto Eleo. Paclflc Islands. 3,537.98 16.26 16.36 3,355.97 16.63 9.12 2,306,86 13.16 15.30 Similar statistics for troops stationed in the United States during the same period, per thousand strength, were: Admissions for disease, 1,496.84; 622 THEOEY AND PRACTICE OF MILITARY HYGIENE. discharges for disease, 22.28; deaths from disease, 6.56. It is thus evi- dent that service in the tropical islands is about three and one-half times as hazardous as service at home stations. Branch of Service as Affecting Health. — It has long been noted that troops of certain arms are more prone to disease and death than are others; this being explainable by the character of the duties each is re- quired to perform, as well as by the diverse conditions of environment under which they are, through military necessity, forced to exist. As compared with infantry and artillery, the cavaby service may be consid- ered to be somewhat more unhealthful and dangerous to life; this being due to the more arduous nature of the service and to the uncleanly nature of a large part of the duties of the mounted soldier. The chief factor in raising the rates of the cavalry above the mean for the army is, however, due to the much greater liability to accident. In time of peace, for all armies, the mortality and sickness iu the infantry is usually less than in any other of the main branches of the service, but in war this favorable showing does not continue. In the United States army, for the seven years 1890-1896, the rates for disease alone, per thousand enlisted men, divided according to branch of service, were : Infantry Cavalry Artillery Ordnance Engineers Medical department. . . . All others Admissions to hospital. 916.27 1,076.56 1,163.61 1,007.15 1,371.55 468.85 941.51 Constantly non-effective. 27.96 30.87 31.81 25.69 29.88 14.99 30.23 Discharges for disability. 13.67 13.36 15.61 9.79 7. .56 11.24 10.15 Deaths. 4.34 3.98 2.94 7.20 2.84 5.14 5.07 Total losses. 18.01 17.34 18.55 16.99 10.40 16.38 15.23 The high death rate noted in the enlisted strength of the Ordnance Department is probably largely dependent on the greater age of these men ; many being old soldiers, superannuated, unfit to stand hard service and broken in constitution by the hardships of a former active life. For the seven year period above noted the rates for aU causes were : Infantry Cavalry Artillery Ordnance Engineers Medical department. All others Admissions to hospital. 1,154.21 1,464.10 1,457.87 1,187.38 1,684.92 527.04 1,100.03 Constantly non-effective. 35.36 43.93 41.11 31.81 88.45 17.08 34.77 Discharges lor disability. 16.73 6.49 17.61 7.35 18.47 5.30 11.23 10.65 7.88 4.73 12.19 6.09 12.13 6.13 Total losses. 23.31 . 24.86 23.77 31,88 13.61 18.28 18.25 The high rate of admissions among the engineer troops was due to in- juries and malarial fevers, with a considerable excess of alcoholism, bron- chitis, diarrhoea and rheumatism. The disabling causes which .produced the high rate in the cavalry as compared with infantry were injuries, which gave a rate of 387.54 as compared with the infantry rate, 237.94; but the excess of admissions among the cavalry was not thus entirely ac- MILITAKY MORTALITY AND MORBIDITY. 623 counted for. Malarial affections were the principal causes of this excess, but diarrhoea, boils and abscesses, and conjunctivitis also aided in making up the total. Among the officers, for the above period, the sick rate was largest in the artOlery, 980.11 per thousand. Non-efficiency was greatest among officers of the cavalry and artillery — 53.90 and 52.57 respectively. Medi- cal officers had a higher rate (47.07) than infantry officers (46.05). The death rate per thousand among officers, according to branch of service, was as follows : Infantry 8.81 Cavalry ' 10.34 Artillery 6.08 Ordnance 17.41 Engineers 11.07 Medical department 10.30 All others 12.33 Death from injury was relatively more frequent among ordnance officers than in those of other corps. Marvaud gives the following figures as showing the comparative mor- tality in different branches of the French service for the six years 1880- 1885, inclusive. Engineers Light infantry Artillery Cavalry Infantry of the line . . . African light infantry . Foreign legion 5.2 7.0 7.4 8.8 10.3 17.2 19.8 Loss by Invaliding. 14.4 11.7 13.S 13.2 16.6 14.5 8.7 19.6 18.7 30.3 33.0 26.8 31.7 28.5 In the English service, in 1897, the foUowing rates per thousand ob- tained for troops on the home stations. Infantry Royal engineers Cavalry Royal artillery. Foot guards . . . Constantly non-efteotlve. 44.79 17.75 42.39 33.49 63.03 In time of war it is, of course, the troops which are most exposed to the dangers of battle and the hardships ©f campaign which suffer to the great- est extent in respect to sickness and death. Influence of Length of Service upon Morbidity and Mortality. — The most extensive figures for the United States army upon this subject, compiled to include a period of seven years, merely divide the men into those who have had less and those who have had more than one year of service — and these show that recruits during their first year with the colors are especially liable to sickness. For the entire period (1890-1896), the admission rate to hospital of this first class was 2,122.17, while that of the older soldiers was only 1,093.07 — or about one-half as much. ' The non-efficiency for recruits was 61.76, as compared with 32.99 for men of longer service; and their sickness was of such a character as to cause 624 THEORY AND PRACTICE OF MILITARY HYGIEISTE. 24.96 per thousand of their number to be discharged on certificates of disa- bility, as compared with a discharge rate of 14.76 among the others. As to the causes affecting the above figures, the vaccination practised in the case of recruits brought a considerable number of cases on sick re- port; a little over 200 per thousand strength being thus added to their ad- mission rate. With the exception of alcoholism, these young soldiers ap- pear to have been more susceptible to all disabling causes than their more experienced comrades. As illustrative of this may be cited their admis- sion rate for injiuries, 414.91, as compared with 242.93 among the others; for venereal diseases, 156.52, as compared with 65.81; malarial diseases, 137.84, as compared with 70.97, and typhoid fever, 11.22, as compared with 4.68. For the single year 1885, the admissions to hospital in the United States army, according to length of service, were divided as follows : Period. Absolute number In each class. Rate of admissions per 1,000 strength. First year and under . . . Second year Third year Fourth year , Fifth year Sixth year Seventh year Eighth year Ninth year Tenth year . .' Twelfth year Fifteenth year and over 6,205 3,633 3,645 2,249 1,053 1,148 897 639 738 921 1,351 4,587 3,354 1,064 984 967 1,064 901 970 1,057 927 991 1,007 838 For the same year the discharges for disability, divided according to length of service, were as follows : Service. Under 1 year .... 1 year 2 years 3 " •. . Discharges lor disability, per 1,000 strength. 64.9 41.5 33.3 39.0 7 8 9 10 12 15 Service. years Discharges for disability, per 1,000 strength. 15.3 16.1 u 13.3 u 19 6 4 " 16.8 11 23.1 5 " ..• 22.2 22.1 6 " 23.2 For the same year the death rate per thousand strength, according to length of service, was determined to bfe : Less than one year of service 10.90 One year of service 4.80 First five years of service 4.54 Second five years of service 5.22 While the absolute number of men in the army of the United States during the year 1885 can scarcely be regarded as sufficiently large to warrant any exact deductions, it is certainly safe to assume that the proc- esses of elimination in our army are most active by far during the first twelve months of service ; after which the total losses fall below the gen- eral rate for the whole army, not to rise again until the more mature men of ten years' or longer service succumb to infirmity. MILITARY MORTALITY AND MORBIDITY. 625 Viry states that in the French service the annual losses by death and discharge for disability amount approximately to 40 per thousand during the first year of service, 30 per thousand during the second year with the colors and 20 during each of the subsequent years. According to Or- dronaux, statistics for the French army some years ago showed the follow- ing to be the average annual mortality : Service. Loss per 1,000. lyear 7.5 3 years 6.5 8 " 5.2 4 " 4.3 Service. Loss per 1,000. 5 years 3.0 6 " 3.0 7 " 2.0 In comparing the amount of sickness among French soldiers of one year of service with those of two or three, Viry found that in 1888 there were, per thousand of each class, 866 admissions among the former and 432 among the latter; in 1889 the numbers were 859 and 483, and in 1890 they were 826 and 559 respectively. The proportionate mortality in the German army for the year 1889-90, in respect to length of service, out of each 1,000 deaths, was as follows : Less than one year of service 433.0 From one to two years' service 348.0 Prom two to three years' service 143.8 From three to four years' service 29.5 Four years' service and upward 146.7 Total 1,000.0 In the discharges for disability in the German army for the same year, out of 8,740 men so discharged 78.3 per cent, owed their incapacity for service to causes existing prior to enlistment. Hence it is not surprising that the majority of men so discharged should have been less than one year with the colors. The percentage of discharges according to length of service was as follows : First year 84.4 Second year 8.6 •Third year 5.0 Fourth year 2.0 Under conditions of tropical service the raw and unseasoned recruits are proportionately even more prone to disease than is the case in temper- ate climates, as is well shown in the following rates for the British troops in India during the year 1897. Average strength. Ad- missions. Deaths. In- validing. RATIOS PER 1,000 Stkenqth. Length of service In India. Ad- missions. Deaths. In- validing. Under 1 year 1 to 3 years 3 " 3 " 3 " 4 " 4 " 5 " 5 " 10 " 10 years and upward . "NTnt Qtflted 11,680 11,580 11,368 10,099 8,013 8,874 1,806 1,111 31,700 18,795 17,929 14,866 10,548 11,728 1,333 36 344 317 208 134 181 151 31 8 302 423 475 446 265 288 59 1857.9 1633.1 1577.1 1473.0 1316.4 1321.6 676.6 • 33.4 39.45 18.74 18.30 13.38 16.35 17.03 17.17 7.30 35.86 36.53 41.78 44.16 33.07 83.45 33.67 fpQtal 64,531 96,834 1,314 2,258 1500.4 18.81 34.99 40 626 THEOEY AND PEACTICE OF MILITARY HYGIENE. Age as Influencing Sickness and Mortality. — In the United States service, for the seven years 1890-1896 inclusive, the relation be- tween disease and age among the enlisted strength existed as follows : Admissions to Constantly non-effective from disease Discharged for Deaths Total losses Age. liospital from disease per disability from disease, per from disease per from disease per 1,000 strength. 1,000 strength. 1,000 strength. 1,000 strength. 1,000 strength. 19 years and less. . . 2,344.79 60.73 33,61 5.33 37.95 20 to 24 years 1,359.63 89.53 14.43 3.98 17.35 25 " 29 " 896.65 36.06 11,96 3.13 15.09 30 " 34 " 755.64 31.58 10,69 3.73 14.43 35 " 39 " 718.43 31.33 10.33 4,83 14.64 40 " 44 " 798,09 34.87 16.65 7.46 34.11 45 " 49 " 755.01 34,16 15.36 10.97 26.23 50 " 54 " 848.48 38.96 81.11 13,18 44.39 55 " 59 " 875.22 34.93 43.55 16.75 60.30 60 years and over . . 1,265.31 73.91 123.64 66.04 188.68 To better emphasise the great wastage of lives and the loss of military efficiency which has resulted from our mistaken policy of enlisting im- mature recruits, the above figures are presented also in diagrammatic form ; no more forcible argument than which for the exclusion of the young and undeveloped from the military service could well be advanced. J-fli: 1 %n^.^U zo-zk ti-'M -io-ti ^i--39 ic-ki ki-ie i7>-J-k SS-S9 . .^T^ j//^ -im - . ■"" -llro - - -X/n ^lerc — . -/Sc^ - - -Z^iTtJ -/JdB -/iffo -/Stx> - . -/i/CS - - -/jm - - -IZFe ~I/Ci> — - le'o — - flo - - gn — - yoe — - ^ic - - $'sa — - t£V — ■ ■ " \ -^H ■r-^ 7^ /i ,, — ,-^ A ' ' ''\ hj ij \\ \ \ - Admissions for disease only. Admissions for all causes. Fig. 330.— Diagram Showing the Influence of Age Upon Admissions to Sick Report in the United States Army, per 1000 of each Class, lor the Seven Years 1890-1896. The younger men, both officers and soldiers, appear particularly sus- ceptible to disease as well as more prone to injury. For 1890-1896 noted above, typhoid fever was observed to be much more prevalent among those under 30 years of age. The rate for this disease in men from 20 to 24 years of age was 10.31; from 25 to 29 years, 5.74; from 30 to 34 years, 2.58. Enlisted men under 25 years of age suffered more from malarial fevers than did officers of the same age ; but with the advance of years the rates of the men came to differ but little from those of their superiors. The • MILITARY MORTALITY AND MORBIDITY. 627 higher rates for venereal disease were given by men under 30 and particu- larly by those under 25 years of age ; but, on the other hand, the rates for alcoholism increased with age. Tuberculosis appeared to be equally dis- tributed among men between the ages of 20 and 50 years, but the excess of diarrhoeal troubles was confined to soldiers under 25 years. Rheumatic fever was not specially prevalent among young men, susceptibility being increased after the age of 40 or 50 years. The rates for pneumonia were considerably larger after 45 years of age — as were also those for kidney disease. In the French army, for the decade 1875-1884, the average annual death rate for all causes, per 1,000 strength, as given by Marvaud, was: Under 30 years of age 6.73 From 20 to 33 years of age 10.93 " 33 " 33 " " 9.38 " 33 " 36 " " 8.59 " 36 " 30 " " 7.14 " 30 " 35 " " 8.51 The class less than 20 years old is not only a very small one, amounting, according to Bertillon, to only about three per cent, of the whole, but the young men composing it are all volunteers and before enrolment are sub- jected to an exceptionally severe physical examination, so that only the best Kves are accepted. Hence, for the French army at large, the first year of service may be considered to begin at the age of 20-22 years. In com- menting on the excessive mortality of the younger soldiers, Marvaud says : " It is duriag the first year of service that the number of deaths attains its maximum, a fact which proves the dangers provoked by acclimation to a military life." The influence of age upon sickness, in time of war, is even more marked than during peace. According to Gayet, iu the campaign of Benin the total losses by deaths and disease and from repatriation, among the French forces, were as follows : Foreign legion 9. 7 per cent . Artillery of the marine 33.3 " Engineers 34.3 " Infantry of the marine 39.0 " African battalion 47.9 " In the two last classes the men were young and ill developed, ranging from 19 to 22 years of age; in the foreign legion the men were older, being between the ages of 25 and 35 years. Influence of Military Rank as Affecting Health. — The report of the surgeon-general for 1897 gives statistics for our army to include the seven years 1890-1896; this being equivalent to a total strength for one year of 14,859 officers and 174,988 enlisted men. These figures show a sick rate of 765.69 per thousand for the officers and 1,258.90 for the men; but the inefficiency rate of the former class was much greater than that of the latter, being 44.27 per thousand as compared with 37.63 per thousand in the case of the enlisted force. The average death rate for officers was 9.56 per thousand, while among the enlisted men the annual mortality was only 6.52 per thousand. Such an unfavorable showing made by the officers as regards the rates for death and inefficiency is largely to be explained by the fact that the military Life of the enlisted soldier practically ceases at 628 THEOEY AND PRACTICE OF MILITARY HYGIENE. the age of 44 years, only 6.50 per cent, of this class remaining in service after that age ; while of the officers included in the tabulation referred to, 37.25 per cent, were over 44 years of age. The latter class, then, while sharing largely with the enlisted men in the hygienic disadvantages of immatiuity, had, in addition, the diseases of beginning old age and the results of long years of hard service to increase its death rate. It is to be noted that during this same period young officers under 25 years had only 784.20 admissions per thousand for disease, where the soldiers of the same age had an admission rate of 1,359.63 ; whUe the non-efficiency rate of the former was 29.61, as compared with the rate of 39.52 for the latter. This would indicate that if the same attention was given to sanitary details by the young soldier as by the young officer, the rate of constant sickness of the former would be correspondingly reduced. The influence of petty rank and length of service with respect to sick- ness in the French army is shown in the subjoined table, constructed from data given by Marvaud covering the year 1888 : Admissions per 1,000 Strength. Detention rooms. Hospitals. Ill 260 567 248 Men having more than one year of service 172 Men having less than one year of service 299 The proportionately large number of non-commissioned officers treated in hospital is explained by Marvaud as being due to lack of suitable ac- commodations in the detention rooms for this class. As illustrating the greater liability of officers to death in modern bat- tles, as compared with the mortality among the enlisted men, the official reports of the British army in the Anglo-Boer war, up to the time of the occupation of Pretoria, showed that for every officer who died of disease thirty-four soldiers died from the same cause, while for every officer who was killed in action or died from wounds, but nine men so lost their lives. Health of Troops during Peace. — The individual significance of the several factors which, taken together, determine the sanitary condition of our army in time of peace wiU be readily appreciated by reference to the table on pages 630 and 631. Diarrhceal affections have the highest admis- sion rate for sickness, but the mortality from this cause is not gi-eat. Mal- arial diseases rank second in frequency, but, as shown by statistics, they are not of severe type and are readily amenable to treatment. Venereal diseases occupy third place in importance as regards admissions, but the constant non-efficiency through their influence is much greater than that- from any other cause. Kheumatism and myalgia together furnish a large proportion of admissions and discharges, as does also bronchitis. The ad- missions for alcoholism are slightly above the general mean, but the rates for death and non-efficiency from this cause are small. All the rates for typhoid fever are low. As to injuries, the several figures for contusions and sprains are all large — those for wounds, excluding gunshot injuries, be- ing considerably lower than those for contusions but stiU somewhat in ex- cess of the general average. MILITAEY MORTALITY AND MORBIDITY. 629 With regard to sickness, deaths and non-efficiency in the British ser- vice for the home stations (see pages 632 and 633), the fact which at once attracts attention is the high ratio given by venereal affections ; the ad- missions from this cause being more than half agara as high as from any other affection or group of diseases. For gonorrhoea, primary and tertiary syphiLLs, the individual rates for non-efficiency are much higher than for such diseases as are summarized as affections of the respiratory and diges- tive systems. The rates for rheumatism and influenza are high, while dis- eases of the skin and of the connective tissue are common. Alcoholism is a minor factor in increasing the rates for sickness, deaths and non- efficiency. Decrease in Rates Under Conditions of Peace. — That improve- ment in the sanitary administration and state of armies is constantly being made will be unhesitatiugly admitted ; yet but few are aware of the stupen- dous progress in this respect which, particularly during the past generation, has been accomplished by military hygiene. Not only is this the case in our own service, but in foreign armies also, and, on reviewing the sanitary conditions which for their time were considered to be excellent, it is ap- parent that still further decrease in the several rates may justly be antici- pated for the future. For the United States army the foHowing charts (see pages 635 and 636) so well illustrate the remarkable decrease in sickness and death which has occurred during the past three-score years that any extended discussion of the matter would seem to be superfluous. Suffice it to say that, in our service, the death rate for the five years preced- ing the Spanish- American war was about three and one-half times less than that for the five years preceding the war with Mexico, while the rate for sickness underwent a diminution of about two and one-third times during the period included by these dates. Since the year 1872 the death rate from all causes has dwindled to about forty per cent, of what it was at that time, while the death rate from sickness alone has fallen almost as much ; and during the same period the rate for admissions to sick report has diminished more than one-half. In the German army, according to official figures recently submitted to the Eeichstag, the number of admissions to hospital from disease, per thousand strength, underwent a decrease from 1,496 in the year 1868 to 867 in 1894. In 1868 the annual death rate per thousand was 6.9, 4.82 in 1879, 3.24 in 1888, and only 2.60 in 1896— a magnificent result, in the attainment of which the due observance of sanitary detail, together with the careful selection of recruits, were main factors. Military epi- demics, in this showing of the German army, have above all lost ground. Smallpox is rare, and caused only two deaths during the twenty years 1873-93. Dysentery was reduced from 6.8 per thousand strength in 1874 to 0.39 in 1894. Typhoid fever gave a rate of sickness of 33.8 per thousand strength in 1868 and 2.4 per thousand in 1894. The typhoid death rate was 2.2 per thousand in 1868 and 0.81 per thousand in 1894. Malaria showed a rate of sickness of 27.6 in 1868 and 0.81 per thousand in 1894; while contagious eye inflammations feU from 7.0 to 1.5 per thousand. 630 THEORY AND PRACTICE OF MILITARY HYGIENE. o o O S > O o la o O s O , H H j^ S s CB < -non ■snoiSBira -PV s s •sm'caa o s 8 s s ^ q PS 5] ; s '^ 5S s o CO Ct3 T-l 55 O l" •rH ;a! *5 ^ ^ ■ m H 02 H W ^ M Eh e =» C) CO b; H SI wS «S ■3I0IS -aoo ■paSjBqo -sip SpiI'EAUI •snoBsiui -py ■JIOIS jSnuKis -noo •paajBqo -sip spii'EAni ■sqjBaa ■snoissim -pV •iiois ilBO'EisnoD JO jaqranu ■aoiAjas am'inojj paSjutlostp spiiT3Aui •mox inojj jnasqy •1TI8UI •TOIdsoti 01 noissjmpv M O O lO QO -H CO «3 in 00 »ri CO »o S- £1 ■ rf T=^ s^~ "2 ', • " ^ ^ ^'i ^ eo 00 (M i:d ^^ o (M o o h S « -^ fe .3 § O § 5« S r3 a ■c i Oofit^amHmSoK. MILITARY MOE,TALITY AND MORBIDITY. 633 ssg-^ ^??§g S ^ cS c3 iS o ^ CO CO r-t S CO Ji S S 3 3 S 04 : oq w w co co co t- iH ^j t-I oi o' ^ »ri w 'jt CO cj eo s s 1-1 M CO r- 1 t- L- CO 1-1 ^ O O >CCOO'*C50r-jC30Si-4COCO O to '^ 1-H -iJH OS O CO O C-l s s s I- 1^ 1— i CO CO OS ■rH '^ ,-1 CO in irt i-i CD i-H O 03 r-l ^ OS CO §5 CO S (^f iH N uf „ a a -s a s S ^ S o s. a 1 to ■s & £■ o 1 1 o u P^ p J P o o B O Q ■S S ta; e O 1-3 il CLh Izi u 634 THEORY AND PRACTICE OF MILITARY HYGIENE. Dbckease op Rates for the Gebman Aemt. Year. Morbidity per 1,000. Mortality per 1,000. Invalided per 1,000. 1879 80 1,174.8 1,136.2 1,135.5 849.6 830.1 850.3 849.2 808.0 804.1 758.9 897.2 4.82 4.82 4.53 4.25 4.16 3.93 3.73 3.79 3.24 3.19 3.30 1880 81 1881 82 1882-83 20.6 1883 84 20.7 1884-85 '■ ■ ■ 20.4 1885 86 23.9 1886 87 20.6 1887-88 21.5 1888 89 19.6 1889-90 . 25.9 According to Boisseau, the mortality of the British army on the home station prior to 1853 was 17.5 per thousand strength. After the improve- ment in the sanitary surroundings of the soldier in that service following the Crimean war, the rates for death and sickness were much diminished, and for the decade 1875-84 had fallen to 7.20 deaths per thousand strength. In 1889 the death rate was 4.57 and the sickness 730.4. In 1890 the deaths rose to 5.53 and the sick rate to 810. For the decade 1887-96 the admissions were 735.9 and the ratio of deaths per thousand strength was 4.68. In 1897 there died only 3.42 per thousand of strength, while the admission rate had fallen to 640.6 per thousand strength. The reduction in the rates of sickness and death in the Italian army during the past twenty-five years has been steadily progressive and prob- ably presents less fluctuation than is the case in any other military service. Year. Admissions to hospital or infirmary per 1,000. Deatti rate per 1,000. Year. Admissions to hospital or infirmary per 1,000. Death rate per 1,000. 1875 1,031 13.3 1887 760 8.7 1876 1,001 11.2 1888 782 8.7 1877 987 10.6 1889 749 8.0 1878 947 10.6 1890 796 7.5 1879 936 9.9 1891 811 9.0 1880 935 11.0 1892 758 7.1 1881 928 10.6 1893 735 6.6 1882 833 10.2 1894 723 5.2 1883 842 11.8 1895 743 7.0 1884 779 11.6 1896 741 5.8 1885 791 10.3 1897 694 4.2 1886 798 9.3 Viry gives the following rates for mortality in the French army as illustrating the better observance of the rules of military hygiene. Period. Mortality per 1,000 strength. Period. Mortality per 1,000 strength. 1812 27.9 21.4 19. 16. 13. 1873-81 90 1820-25 1883 8 15 ' 1846 1889 5 39 1846-58 1890 5.81 1862-72 MILITARY MORTALITY AND MORBIDITY. 635 Fig 321 —Chart Showing Beauctlon In Death Rate, per Thousand Strength, In the TTnited States Army, un- der Conditions ot Peace, (or the Period 1840-1898. Death rate from all causes Death rate Irom disease alone Dewey states that in the French service the average annual death rate was 8.43 per thousand strength for the seven years 1880-86, and that it sank to a yearly average of 6.63 for the seven succeeding years. This decreased death rate is naturally consequent to a lessened amount of sick- ness, as the following figures from Marvaud illustrate : 636 THEORY AND PRACTICE OF MILITARY HYGIENE. Period. 1862-65. 1866-69. 1884-87. Admissions to liospital per 1,000 strength (admissions to infirmaries and cases treated in quarters not 264.5 23.3 259.5 22.1 177.0 Bate of constant non-eiiectives per 1,000 strength . . . 14.0 MILITARY MORTALITY AND MORBIDITY. 637 Lindley, writing in 1892, states that during the preceding forty years the death rates in the Prussian and Belgian armies had shrunk to two- fifths, the English and Russian rates had fallen to one-half, and the French rate had diminished to one-third. These figures may probably be accepted as being approximately correct. The lamentable conditions revealed by the above statistics as existing until even within the present generation, in the armies of all nations, were undoubtedly largely due to ignorance of first causes of disease, by which measures for its prevention could not be intelligently apphed, as well as to an insuf&cient knowledge of hygiene and lack of appreciation as to its value from a military standpoint. An additional factor of no mean importance, however, was to be found in the former anomalous and in- ferior condition of the medical officer, his lack of authority to recommend in sanitary matters and his powerlessness to control or remedy existing conditions. It was long held that his duties were merely to care for the sick and wovmded, and any recommendations bearing on the general care or management of the men were deemed intrusive and as such usually dis- regarded and resented. The comparatively recent conferring of advisory powers upon the medical officer for sanitary purposes has undoubtedly been a potent factor in the gradual betterment of the sanitary condition, and hence efficiency, of the soldier; and when the former is invested with ac- tual authority upon all matters bearing upon the health of troops, with ex- ecutive powers as well as advisory privileges, a still further improvement in this direction may be expected. Although during the past one or two generations a marked diminution has occurred in the sickness, mortality and non-efficiency among the troops of the United States and those of European nations upon the home sta- tions, the same unfortimately cannot be said with regard to white troops doing colonial duty in tropical climates. For such troops these rates continue to be high, and no great improvement in their sanitary state, as evidenced by statistics, appears to have resulted for many years. Since the hygienic requirements for each military establishment, wherever its troops may be stationed, must be accepted as being the same for all cir- cumstances, the conclusion is obvious that climatic conditions in the tropics furnish a potent obstacle against a constant reduction in rates pro- portionate to that which has occurred on the home stations. While un- doubtedly much has been done during the past generation to render mili- tary service in hot countries less inimical to life and health, the fact none the less remains that sanitary progress in the low latitudes has fallen far short of that obtaining in more temperate climates. It is evident that figures illustrating this point are best furnished by the records of the Brit- ish service, and these are briefly compared as follows : West Indies . Ceylon Period. Decade 1875-84 Decade 1886-95 Year 1896 Decade 1875-84 Decade 1886-95. Year Admissions to hospital per 1,500. 885.0 1,115.7 1,190.3 1,085.4 1,004.1 1,321.1 Deaths per 1,000. 15.36 9.23 6.19 14.51 11.38 8.33 Days lost per man. 16.26 83.67 28.69 20.97 31.10 33.76 638 THEORY AND PEACTICE OF MILITAEY HYGIENE. CMna India Egypt and Cyprus Straits Settlements Decade 1875-84 Decade 1886-95 Year 1896 Decade 1875-84 Decade 1886-95 Year 1896 Decade 1875-84 Decade 1886-95 Year 1896 Decade 1875-84 Decade 1886-95 Year 1896 Admissions to hospital per 1,000. 1,030.4 1,256.0 1,856.5 1,482.9 1,453.5 1,386.7 No 1,069.7 822.3 No 1,079.4 1,074.7 Deatlis per 1,000. 10.58 11.44 7.48 17.43 15.52 15.29 figures gi 16.30 13.28 figures gi 7.27 Days lost per man. 18.07 82.41 32.05 23.06 30.26 34.35 ven. 24.56 23.11 ven. 25.58 36.46 From these figures it is evident that while there was a considerable diminution in the morbidity and mortality rates for the West Indies and Ceylon duriag the past twenty years, but little improvement has occurred in the general rate for China, Egypt and Cyprus. In India, a country long occupied by a large military force of Europeans and one in which the greatest improvement might reasonably be expected to have occurred, the rates are practically what they were two decades ago — the death rate of British troops at home having fallen from 7.20 to 3.58 per thousand, while the mortality for India fell only from 17.43 to 15.29 during the same period. Further, the several rates for the Straits Settlements have actually ia- creased during the past ten years. In this respect the experience of Great Britain is duplicated by that of the French service, in which in 1862 the mortality for troops throughout France was 9.42 and for those in Algeria 12.21 per thousand; while in 1890 the death rate for troops at home was 5.81 and for those in Algeria 11.94 per thousand. "War as Affecting the Health of Armies. — ^The rates of sickness and death for troops during campaign, independent of the circumstances which accompany conflict, are chiefly influenced by the sanitary standards maintained, and, as aheady stated, it is difficult to cite campaigns in which the death rate from sickness has not been greater than that from casualty. The diseases observed during continued warfare, according to Laveran, are largely' brought about by four chief influences: atmospheric, exhak,- tions from the soil, evil condition of the latrines and poor food. The atmospheric exposure to which the soldier is often subjected is one of the greatest hardships of a campaign. Sleeping on the bare ground and often drenched with rain, standing in trenches exposed to snow and cold, or making long marches under a tropical sun, are a few of the influences by which he is debilitated and his constitution impaired. Service in a malarious country is notoriously productive of disease, while ill policed sinks are potent factors in the occurrence of typhoid and dysentery. The influence of insuflicient or improper food in lowering the resisting powers of the soldier is well recognized. Excessive fatigue and moral influences also play an important part in determining the sick rate, it being well established that victorious forces have less sickness than armies which MILITARY MOETALITY AND MORBIDITY. 639 have been beaten and demoralked. The endemic and epidemic diseases of an occupied country, together with the influence of a change of climate, to lO ■•J- m CM o o 00 N (D lO tn CM lO tn CM o a> 00 s CD lO r i Ul (T o = = ^ :— J 1 = ^ = ^ - = = M 11 g = 1 ^ n i H tl n J - TT - Q % R g ■ 1 1 ^ _ 1 Q H § 1 1 ' i i II H y 1 f] 1 1 J. i B fTR P 1 II 1 a UN 1 1 R o z < s 1- £ a. 01 III H < 1 ( 1 L 3 C C 3 u i 1 fi > u. Ul > t u ul S f i °£ Is [u o: ft! 2 Ul a z to ii 11 p a. £ o o i 3 Ul I a 3 •s 1 S =! tS ■2sa I mooo n ■a +3 •c a *(>, ■-SI CO cow "CO aggravate also to a considerable degree the sickness and mortality of an expeditionary corps. For our own service the influence of hostilities upon mortality from 640 THEORY AND PRACTICE OE MILITARY HYGIENE. disease is well illustrated in the preceding chart, showing, as it does, the rates for certain affections in the United States army, during the Civil War, for periods before and subsequent to that war, and also as compared with the death rates for the corresponding class in civil life. As com- pared with the mortality from continued fevers — which affections may be considered, in the light of present knowledge, as chiefly of typhoid nature — war brought about an increase of tenfold. Malarial diseases were doubled and diarrhoea and dysentery tripled. Deaths from eruptive fevers became about twenty-two times as frequent as they were before the war, while those from diseases of the respiratory organs were more than quadrupled. Camp life appeared to have little influence in affecting the mortality from nervous affections. Deaths from diseases of the circulatory and digestive organs were practically doubled in frequency, as was also the mortality from consumption. Eheuniatism, as regards a fatal termination, and. con- trary to expectation, was not increased; but scurvy — the former bane of armies in the field — was doubled. The average annual death rates from disease during the entire war was 53.48 per thousand strength among white troops, while it was 18.98 for these troops during the eighteen years before the war, excluding the two years of hostilities against Mexico, and only barely over 6 per thousand for the decade subsequent to the war. The following table shows the influence of the war with Spain upon the rates for sickness and death, as regards the prevalence of certain classes of diseases: Table Giving Figures fob, the Comparison of the -Year op Peace, 1897, with THE Year of War, 1898. United States Army. Group. Infectious diseases, general and local Diseases of nutrition Diseases of the nervous system Diseases of the digestive system. . . Diseases of the circulatory system . Diseases of the respiratory system. Diseases of the genito-urinary sys- tem Diseases of the lymphatic system and ductless glands Diseases of the muscles, bones and joints Diseases of the Integument and subcutaneous connective tissues. Diseases of the organs of special sense Unclasslfled Total for diseases Total for injuries Total for all causes Admissions PER 1,000 Strength. 1897. 326.10 2.05 56.94 244.05 4.68 77.74 9.76 2.36 72.52 72.55 24.47 2.44 896.53 1,186.61 1,034.97 3.49 52.81 505.71 6.73 144.50 11.77 3.22 77.34 60.57 17.39 19.17 1,937.74 209.23 2,146.94 Constantly Discharges NON- Deaths FOR EFFECTIVE PER 1,000 DISABILITY PER 1,000 Strength. | PER 1,000 Strength. Strength. 1897. 1898. 1897. 1898. 1897. 1898. 12.59 57.90 I.a5 15.99 1.2R 2.14 .19 .21 .09 .29 .13 1.63 1.33 .33 .92 1.79 .86 3.75 7.01 .55 3.11 .55 .58 .41 .60 .37 .49 .95 .96 1.64 2.04 .22 .96 .40 .26 .80 .87 .22 .24 .44 .43 .17 .17 .04 .02 2.85 2.70 .31 1.33 1.70 1.06 .30 .04 .93 .79 .04 .58 .63 .09 .59 .04 .02 26.73 69.09 3.14 24.94 7.60 7.40 9.12 13.74 1.97 8.41 2.01 4.18 35.85 82.83 5.11 33.35 9.61 11.58 Total Losses per 1,000 Strength. 1897. 2.63 .29 2.12 1.10 1.32 .63 .66 .04 1.31 10.74 14.73 18.13 .22 1.78 3.09 1.45 1.33 .67 .03 1.33 .34 .62 .02 32.34 13.59 44.93 As showing the effect of campaign on sick rates the British Afghanis- tan expedition, in 1879, furnishes a good example. The rates per thou- sand for 1878, the year preceding the war, and the two years of the war, are as follows : MILITARY MORTALITY AND MORBIDITY. 641 Tear. Admissions lor disease per 1,000 strength. Deaths Irom disease per 1,000 strength. 1878 340.1 1316.5 1107.1 2.83 1879 74.63 1880 30.64 All things being considered, it is safe to assume that the outbreak of hostilities will be followed by a vast increase in the death rate from dis- ease, probably from six to twelve or more times that normally occurring ia peace; the proportion naturally varying with the character of the campaign, the climatic conditions to be en- countered, the local dis- eases to be undergone, the efficiency of the commissary and trans- portation departments, the employment of sea- soned or unseasoned troops and many other factors. The rate of admissions to sick re- port from disease iu time of war is not, how- ever, increased propor- tionately to the death rate — a fact sufficiently proving the more serious nature of the diseases affecting troops in the field. ' As to the rate for non-efficiency, this is largely dependent upon the ratio for admissions, and naturally bears in its fluctuations a close relationship to the prevalence and character of disease. If the records of the Spanish- American war be accepted as typical in this respect, no great difference in the rates for dis- charge by reason of disability, in peace or war, may be anticipated. In comparing the results of the Spanish- American war with the cor- responding period of the Civil War the advantage is much in favor of the former, although the progress of disease, by months, is quite dissimilar. It is particularly noticeable that not only was the death rate during the war with Spain reduced by 43.9 per cent, as compared with the struggle of the previous generation, but the amount of epidemic typhoid, largely resulting from the inexperience of the volunteer troops, rapidly decreased as a result of scientific sanitary measures enforced as soon as the magni- tude of the typhoid outbreak was fully imderstood. 41 / FROM DIfiFAfiE 1 ^"X '^"-^ FROM TYPHOID FEVER « mortality] ,„,„,,^,, 1 YEAR 1899*9 \ FROM TYPHOID FEVER 'S MAY 1 JUNE 1 JULY [ AUG. |8EPT.I OCT. | NOV. | DEC. | JAN". | FEB. | MAfi. | APR. (in fiO _5.5. BO / \ 5.5 / \ 50 45 \ / 45 40 1 \ 1 ^ y \ / 40 -8.5. 1 j \ / ^ .3 5- -3,0- i : / 3JL -2.B- 1 ," y \ .8.5. '!>,ri __ A \ ,-^ 80 1.5 / / •:X \, y 1 n .^ / _ y \. \ y XO- 05 / ' 05 ■ ' ■■:■*■ '•• ••••■ Fio. 324.— Mortality from all Diseases and from Typhoid Fever dur- ing the War with Spain and during the Corresponding Period of the Clvn War. (After Sternberg.) 642 THEORY AND PRACTICE OF MILITARY HYGIENE. compakison of monthly death rates per 1,000, prom disease, during the First Year op the Civil War and the War with Spain. Months. May June July August . . . September October... , November December January . . . February , March April Annual . . 1861-83. Mean strength. 16,161 66,950 71,135 112,359 165,136 256,884 301,848 343,184 853,760 337,734 338,878 410,416 239,452 Number of deaths. 18 55 106 342 365 725 1,145 1,471 1,593 1,346 i,r,7r, 1,881 10,532 Ratio per 1,000 of M.S. 1.11 .82 1.49 2.15 3.31 2.83 3.79 4.29 4.52 4.11 4.79 4.58 45.86 Ratio per 1,000 ol M.S. 0.36 .44 ■ 1.72 5.31 5.89 3.17 1.51 .84 .85 .87 .90 .71 25.73 Number of deaths. 43 90 451 1,400 1,541 809 365 201 180 156 133 80 5,438 Mean strength. 163,726 202,526 362,613 268,507 261,834 355,000 343,000 340,000 211,000 180,000 136,000 113,000 211,350 As already intimated, so many factors combine to determine mortality from sickness in campaign that any attempt at the close comparison ia this respect of different wars — carried on under entirely different condi- tions — can yield only misleading results. General deductions can of course be drawn, and hence the following figures may be of advantage as well as interest : Deaths from Disease During Certain Wars of the Present Century. (After Bradford.) Name of War. Nation. Year or period. Mortality from disease per 1,000 strength. 1809 346.9 1824 690.0 1846-48 100.0 1854 230.0 1863 118.0 1863 40.0 1863 60.0 1870-71 18.6 1878-80 93.7 1888-89 380.0 1895 300.0 1895 14.8 1898 25.0 Walclieren expedition West Coast of Africa Mexican Crimean Chinese Civil War Civil War Franco-Prussian Afghanistan Soudan Madagascar Chino-Japanese Spanish- American . . . Great Britain Great Britain United States Great Britain France United States United States Germany .... Great Britain Prance France Japan United States With regard to the results of campaigning under tropical conditions, the most satisfactory data are naturally furnished by the two great colo- nizing powers, GreEtt Britain and France. The figures given for these ser- vices are so widely dissimilar, however, as to furnish no foundation for any general conclusions based upon them both. For purposes of compari- son merely, they are certainly valuable — the French having little reason to be proud of their sanitary showiag, as evidenced in the following table. MILITARY iMOKTALirV AND MORBIDITY. (ii;] Tmu.k of 1\Iii|!tai,ity KiioM DisKAsK, IN MciUE Kkcknt C'ami'akins in TROPICAIj C'orNTHiKS, SiiowiNii KviK ()!•' ni'.A'i'ii PK.K l.ODlt SPKioNcirn. (Al'lcr Bradford.) Dlilisli Ivxiic'dllions. Soudan iMii&lioualaud S\iakim Soudiui China (Talicn-wun). .. A.-^hanti K.nypl Alnssiniii Oaii'ika (iaika., ; IS7T-78 Vhmn Kiolil Force tS(il) Matabi'leland ' 1S!i(i ISS!) KS7G 1H85 USSr)-8G IMDo-Oli I s(;7-(is Ashanti Zuhiland .... Chilml Nilo l>oii!;'o1a . . . . At'i;iianist!VU. isr4, 1S7!) isM.i-8r) isjm 187S-8() (i o V A 1 4 ;> 6 5 f? 13 1 14 14 !) It) 1 7 04 s 05 I Oli 4 4(i () !i;! 7 I^»ncb Kxpciiltioiis. Tonkin Tunis Mexico Toiikiu Dahomey Tonkin Tonkin Coehin-C'hina. Soudan t\iehiu-C"hina. China Tonlvin Soudan Soudan Soudan Soudan Jhidanasear . . SS4 60,0 8S1 61.0 8(iO- -03 71.0 s,sr> 711.0 sii:! 87.0 S,S(! 9it.0 8S7 100.0 sii3 107.0 887- -88 110.0 8(iO 117.0 8(iO 118.0 8SS 133.0 885- -80 000.0 88(i- -87 000 . 887- -88 005.0 S88- -81) 080.0 8!)5 300.0 The (.'usualties of tho ivcenl Freuch exiiediliou iu Madagasoar are thus o'ivou b>' (.iavcl : Killed by I he enemy AVounded lleaths from sickness Sick, more than 15,000, or 85 per I'eut. of the whole force. 04 5,600 From the table given above it will be observed that with the exception of the .Afghauistau eanipaigi\, in which the high mortality was largely the result of au outbreak of cliolera, the most uuhealthful of seveiiteeii English expeditions in wanu climates had a lower death rate than the healthiest of an equal number of French t'ampaigns imdev jiresumably similar conditions of temperature. The l>ritish expedition against the Ashantis in 1874 certainly demonstrated the ethciency of military hygiene under the most unhealtliful conditions; and, in the excellent results obtained, the second expedition ag-ainst this same tribe, in ISlHi, far surpassed tlte Krst, As compared with the French ]\ladag-ascar expedition, the mortality rate in the second Ashanti expedition was only about oi\e tifty-tliirdof the losses of the French imtlcr probably no more uuhealthful conditions. In our own expedi- tioT\ against ^Innila, during tlie war with Spain, the results were admutible, only S per tliousand dying from disease. Duriug the Cuban insurrection the Spanish are reported, for the year 1S97, to have had a death rate of oti per thousand fi-om all causes. The admissions to hospitiil for the same period were 1,900 per thousand, of which 420 per thousand were for mal- aria. Ihiring 1S97 the Siuxuish troops appeared to have sufi'ered but little from yellow fever; tliis beuig- probably due to an immimity to this disease acquired through prex'ious visitations. Tliat constant exposm-e to infec- tious ^^isease of all kinds, and not only yellow fever, does actually exert a seasoning influence on the sur\ i\"ors and reduce their mortality is well known. As illustmt ing this point, it may be noted that the sick rate of the colored ti'oops during the tlvil ^Var fell fi'om 4,092 per thousand during .the first vcar of their service to 2,797 in Uie last, while their death rate 644 THEOEY AJSTD PRACTICE OF MILITARY HYGIENE. dropped from 211 to 94 per thousand strength. The total rates for sick- ness of all troops during the Civil War underwent considerable dimiaution, as follows : First year, admissions per 1,000 strength 2,983 Second year, admissions per 1,000 strength 3,696 Third year, admissions per 1,000 strength 2,210 In this connection the chart already given in connection with the influ- ence of race as affecting the prevalence of disease is of interest. It is not, however, during active wars or on expeditions that the highest mortality is observed among troops in the field. When an army is con- demned to inaction through a siege, for purposes of mobilization, or even in cantonments after a laborious expedition, sickness rages with greater violence. The typhus that tried the Crimean army occurred in the win- ter after the capture of Sebastopol and after conclusion of the armistice ; and examples might be indefinitely multiplied in our own service to show that the stationary force during war is an unhealthy force. In January, 1862, the medical director of the Army of the West, then in winter quar- ters, reported 13.5 per cent, of the total strength as being excused from duty by reason of sickness. In August, 1861, of some troops encamped on the Arlington flats on the Potomac, 33 per cent, were reported as sick with diarrhoea and malarial fever. During the war with Spain the typhoid epi- demics, as is well known, occurred in the larger fixed camps. Axl excel- lent illustration of this point is found in the condition of the French troops during the Crimean War, a struggle from which so many sanitary lessons have been drawn. According to Eawlinson, estimates as to the sickness among these troops, for the winter of 1854-55, were as follows: Month. strength. sick in Hospital. October 46,000 55,000 65,000 75,000 88,000 3,300 5,000 6,000 Januarv » 9,000 8,000 These figures do not include the sick treated in the regimental infirmaries or in the hospitals at Constantinople. Comparison of Military Medical Statistics. — It is a matter of the greatest difficulty, if not indeed impossible, to compare the sanitary conditions of various armies with accuracy, since their statistical tables are often differently constructed, the physical requirements for recruits are not identical and diverse regulations as to discharge for disability prevail. In attempiiig to institute such comparisons it is well to appreciate at the outset that a sick rate can be kept low by excluding the doubtful or milder cases from the benefits of quarters or hospital, and so preventing them from appearing on the official records ; that the sick rates, mortality ^nd constant non-efficiency can be held down by a searching system of discharge for disability, and that the total loss — as shown by the sum of the rates for death and discharge — is, in determining the sanitary state of an army, of much more, importance than either of its complementary fac- tors. MILITAEY MORTALITY AND MORBIDITY. 645 In comparing the rates of ova service with those of foreign armies, the admission rate is the one which, by its magnitude, attracts attention. This higher rate of admissions, however, does not in itself imply a greater prevalence of disease among the troops of the United States ; since with us, in contradiction to the practice in other armies, the soldier is officially taken on sick report whenever he is excused by the medical officer from any part of his duty, whatever be the cause. When it is observed, as was the case in the year 1888, that 796.89 admissions per thousand strength from the Italian army resulted in a death rate of 9.31, while 1,270.73 admissions for each thousand United States soldiers for the same period — divided into 621.61 cases admitted into hospital and 649.12 treated in quarters — ^had a mortality of only 8.15 per thousand, it is evident that the admissions in the two instances , the rates for discharge for disability not varying greatly, do not constitute facts of equal gravity and are there- fore not available for comparison. The rate for constant non-efficiency is obviously largely dependent upon the admission rate and that of discharge for disability, and reflects, to a considerable degree, their variations. Taken by itself the rate is mislead- ing, and it acquires a certain value only when considered in connection with other rates, particularly that for admissions. As between services, for the reasons already given, it is evident that non-efficiency rates are not susceptible of proper comparison. A consideration of the death rate alone, as a means of comparison be- tween several armies, is wholly unreliable and merely productive of error ; since, as above stated, it can be markedly reduced by the removal from the service of those affected with or predisposed to disease. Of all the ratios which go to determine the healthfulness of an army, as shown by statistics, that giving the discharge for disability is of the greatest importance. In its relation to military morbidity it is at once evident that the admissions to hospital wUl be largely furnished by the physically less sound, and that a prompt and proportionate dimioution in the sick rate must follow the elimination of these weaklings by their dis- charge from the service. Further, the number of men withdrawn from the aggregate strength of the command — the rate of non-effectiveness from disease or injury — is not a factor of equal importance in all armies and can- not be justly used for purposes of comparison. It imdoubtedly embodies the number of admissions and the gravity of the cases so admitted ; but it is obvious that the constant non-efficiency as well as the admission rate varies iuversely with the rigor of the system of discharge. As to mortal- ity, this also depends upon the physical standard maintained, and, as shown in the German army, a low death rate is naturally consequent to the early elimination of those soldiers who are predisposed to or actually affected with disease. Hence the rate of discharge for disability is the controlling factor in determining the value of the rates of admissions, deaths and con- stant non -efficiency ; while it is itself largely dependent upon the physical standards to which the recruit, before enlistment, is required to conform. To institute accurate comparisons, therefore, a constant, unvarying stand- ard for discharge for disability should obtain in the several military forces to be compared; and such a constant standard does not — and practically cannot — exist. Eequirements as to discharge for disability necessarily 646 THEOEY AND PRACTICE OF MILITARY HYGIENE. vary with tlie customs of each military service, and, to a certain degree, with the personal equation of each medical officer. As an instance of the former, it may be noted that the Germans are especially assiduous in promptly removing the tuberculous from their armies, while we, on the other hand, maintain a sanitarium for soldiers affected with this disease; and this single source of error, to which might be added many other less aggravated instances, prevents a comparison of the sickness, mortahty and non-efficiency upon anything like equal premises. If it be admitted, how- ever, that the physical requirements for the recruits of various armies are approximately the same, the total losses, irrespective of either non-effi- ciency or admission rate, should afford a somewhat inaccurate but stiU the most available and satisfactory method of determining the comparative health and physical efficiency of various military services. The following figures, taken from Marvaud, show the annual sick rates, mortality, loss by discharge and total losses in various European armies for a period about twelve or fifteen years ago : Year or period. Admissions to hospital or infirmary per 1,000 strength. Death rate per 1,000 strength. Discharges lor disability per 1,000 strength. Total losses per 1,000 strength. Belgium Austria Great Britain (home stations) France (home stations) Germany , Italy Russia Spain 1887-88 1887 1884-85 1888 1883-84 1887 1880-84 1886 338* 995 1 877 500 849 760 845 3.9 6.9 5.3 6.1 3.9 13.5 17.0 15.0 1 30.0 31.0 39.0 38.0 31.3 30.8 30.9 21.9 25.3 27.1 32.9 36.7 40.2 44.3 * General hospitals only. f Including detention in barracks. X Not including temporary invalids. During the year 1888 the total admissions per thousand strength in the United States army amounted to 1,270.73, the deaths were 8.15 per thousand, the constant non-effectives were 41.91 per thousand, the dis- charges for disability 27.75 per thousand. These figures give a total annual loss of 35.90 — thus making our sanitary showing for that time inferior to that of the above-named nations except Italy, Eussia and Spain; all countries notoriously less advanced in matters pertaining to hygiene. It can, however, scarcely be beUeved that our men, under equal conditions of selection, broke down nearly twice as readily as the Belgian or Austrian soldiers and half again as rapidly as the British soldiers, and hence the conclusion would seem to be inevitable from the above figures that our troops were at that time examined on enlistment with a laxity as to their physical condition which did not obtain in foreign services. This view is further strengthened by the fact that during the same year (1888) out of 742 men discharged on certificates of disability, in 129 instances the disability was specifically declared to have existed prior to enlistment. About this time the large number of discharges for disability attracted the attention of the authorities, and recruiting officers were warned to be more strict in their examinations for enlistment ; while a general order required that all men recommended for discharge on account of disability be sent to MILITAEY MORTALITY AND MORBIDITY. 647 the headquarters of each military department, for observation by the chief surgeon, pending final action in their cases. As a result of these require- ments the rates for discharge were decreased by nearly one-half in a single year, since which time even further diminution has taken place. For the year 1897 the rate for discharge on accoimtof disability was only 9.61 per thousand as compared with 27.75 during 1888. On comparing the statis- tics of the above armies for a more recent period — excluding France and Spain, for which countries no later figures are obtainable — the relative status of the United States service is found to be as follows : Country. Admissions to hospital or infirmary per 1,000 strength. Death rate per 1,000 [strength. Discharges for disability per 1,000 strength. Total losses per 1,000 strength. Germany Belgium United States Great Britain (home stations) Italy . i , Russia , Austria , 1895 1897 1897 1897 1897 1896 1897 819.9 429.3 1,186.61 640.6 694.0 314.6 332.7 2.6 2.0 5.11 3.42 4.2 5.40 4.0 9.0 12.4 9.61 19.87 21.2 24.9 37.5 11.6 14.4 14.72 28.29 25.4 80.30 41.5 It is evident from the above that much has been accomplished during the past decade toward improving the effectiveness and sanitary condition of OUR army, and it is safe to assume that at the present time the United States soldier not only represents a higher standard of physical excellence but is better cared for than is the man-at-arms of nearly every other mili- tary service. Although, as stated, attempts at the comparison of statistics of differ- ent armies are at best necessarily inaccurate and unsatisfactory, within the limits of the same service such action may be both feasible and desirable ; the standard for the health of an army, as expressed by Smart, being its own best annual record. Outside of unusual vicissitudes, exposure and epi- demics, and of the unsanitary conditions which bring disease and death into the ranks of a military command during campaign, the sanitary sur- roundings of the soldier do not vary much from year to year except as they are modified by intelligent efforts for their improvement. What has been accomplished ia the past should therefore be effected in the present; or satisfactory explanation should be given of the cause of failure, which may thus be converted into a source of protection for the future. CHAPTEE XV. DISEASES OF THE SOLDIER. In aU its aspects, whatever be the special methods employed for its attainment, military hygiene has for its object the prevention of disease. This, viewed in the abstract and stripped of humanitarian considerations, has relation to military efficiency — which, in its turn, depends upon the proportion of an army which is maintained in a condition vigorously to perform such military duties as may be required. The numerical strength of the forces wfiich contending nations are able to put into the field influences the operations which they perform by equivalence or disparity of numbers. As expressed by Napoleon, "Providence is on the side of the largest bat- talions." Eor aU practical purposes, it matters little to a commander why his force is small or how it is reduced, if the reason of its inferiority or the cause of its reduction is brought about by agencies beyond his con- trol. But if the agencies are known, if they can be controlled and their effects are remediable, it becomes a matter of the greatest importance to ascertain the way through which they act and how their effects may be limited or obviated, if the causes themselves cannot be removed. Disease operates in reducing strength in various ways ; but the point of practical importance to military authorities, and especially to the strategist in the field, is that disease produces absence — this being due to death, to inefli- ciency from sickness and to the necessity of caring for the sick. Eeduction in strength by death, especially to armies in the field, is of course worse in its effects than if the dead men had never been enlisted. Their loss from the military standpoint, which presumes that soldiers are constantly effective, is unexpected, and plans have frequently to be modified accord- dingly. Upon the deceased have been expended training, provisions and money for which there is no return, yet which were intended to provide an effective force. By the sickness and death of these men the morale of the survivors may be lowered ; and in most instances the dead have played an important part in the dissemination of morbific agents among their fellows. Absence from disease is even more fatal to the success of mili- tary operations than is absence from death. It is embarrassing as regards strategy and supply when a number of sick have to be retained with an army during active campaign ; and the length of time during which such cases require treatment therefore becomes a matter of decided military im- portance. From the sick, also, disease may be transmitted, and thus the welfare of the majority is menaced. Further, so long as sick soldiers are retained in the service, they require an outlay of money and energy for their care and support, and — of the greatest military importance — the places occupied by them in their respective organisations, so long as they are neither dead nor discharged for disability, cannot be fiUed by the enlistment DISEASES OF THE SOLDIER. 649 of more healthy and effective individuals. Absence in care of the sick does not now greatly diminish the fighting strength, as was formerly the case, but it implies the necessity for a correspondingly large force of. non- combatants, for whose needs additional transportation must be provided — thus sacrificing much of that celerity of movement upon which the success of modern military operations depends. There are no diseases peculiar to the soldier; those by which he is chiefly affected are such as not infrequently occur among males of the mili- tary age in civil life. Military conditions are frequently such, however, that the germs of infectious disease are widely disseminated among an especially susceptible body of men — and hence a larger number are at- tacked and succumb than would probably have been the case in civH life. Not only is it true that the factors predisposing to deviation from the stand- ards of health are greatly increased in potency, but the course of the dis- ease itself, after its establishment, may be markedly influenced. Thus the diseases developed in the military establishment are characterized by their unusually severe type, the regularity with which outbreaks of some affec- tions recur and the frequent tendency of others to become endemo-epidemic. The prevailing diseases in armies are, naturally, largely acute, and a large proportion of them are zymotic and hence theoretically preventable. Excluding traumatism, the causes which chiefly impair the health and efficiency of troops, in garrison or during campaign, may be grouped ac- cording to their relative importance, as follows : (1) Diseases of an infectious character, the spread of which, in the mili- tary service, is favored by the aggregation of young and susceptible in- dividuals, ignorant or careless in regard to matters of personal hygiene, living under conditions implying intimate personal relationship, constant contact and, frequently, overcrowding. In many instances, the necessities of service require an existence in unhealthful localities favorable to the development of pathogenic micro-organisms, and under circumstances in which their opportunities for dissemination and entrance into the system are much greater than in civil life. In addition, the development of these diseases is often markedly favored by depression of the powers of vital re- sistance, depending upon great fatigue, exposure to inclemencies of weather, insufficient or improper food, impure water and vitiated air. These diseases assume far greater importance during active service in the field than in garrison, being the chief cause of inefficiency among troops during cam- paign. (2) Diseases due to immoral or intemperate habits, as favored by an en- forced celibacy, the absence of wholesome home restraint and the monotony often attaching to garrison life. These diseases are factors of the first im- portance in time of peace in raising the sick-rates of an army, but during active warfare or field service they sink into comparative insignificance. Affections of this character are discussed separately in the chapter devoted to a consideration of the habits of the soldier. (3) Diseases the specific causative agents of which are unknown, but which appear to be largely excited by exposure to cold, wet and dampness, whether they be found in camp or garrison. These affections have but little tendency toward a fatal result, and their importance from the military standpoint lies in the considerable amount of temporary inefficiency for ser- 650 THEORY AND PRACTICE OF MILITARY HYGIENE. vice which they produce. The proportion of soldiers who are temporarily" incapacitated for all or part of their duty, from these causes, is always, large. (4) Affections due to extremes of temperature. Such are obviously re- lated to climate and season and are largely influenced by nature of service ,•: beiag naturally much more frequent among troops on campaign than among those in garrison. Affections of this character are subsequently considered in connection with the hygiene of hot and cold climates. (5) Diseases produced by food of unsound or unhealthful character. Though possible at any time, such are far more liable to occur during war or in the field, where greater laxity as regards inspection usually prevails and where deterioration in quality is more liable to occur during transpor- tation. Diseases due to such causes have already been considered in con- nection with the several articles of the ration. (6) Disease due to an improper dietary ; this being largely dependent upon facility of supply and transportation, and hence being obviously more frequent among troops on active campaign or serving at remote, isolated and newly estabKshed stations. With the present liberal and scientifically constructed ration, inefficiency from this cause should, in the future, be rare. (7) Diseases directly induced by military service. These may be of functional or organic nature and are largely dependent upon the muscular labor involved in the execution of military movements, the method of dis- posing the equipment upon the person and the mental condition often result- ing from field service and conflict. Pathological conditions of this character are rarely observed in garrison but are by no means infrequent during campaign. They are sometimes seen, in civil life, in individuals whose callings require the frequent performance of exhausting labor. In the foUowing consideration of the diseases of the soldier, it is obvi- ous that only such affections as exert a certain positive influence upon military efficiency require discussion. To consider in this connection a number of rare affections, from the liability to which the soldier is no more free than the young man of the military class in civil life and upon the occurrence of which neither positive nor negative influence appears to be exerted by military service, is clearly both unnecessary and undesirable. THE INFECTIVE DISEASES. There can be no infectious disease without the presence of the specific causative agent. In addition, there must be an individual susceptibUity to the disease, on the part of the person attacked, which permits inva- sion by and multiplication on the part of the micro-organism concerned. Should anything interfere with the coSperation of these two factors, the disease cannot occur. It is clear, therefore, that for infection to take place the attacking powers must be strong or the resistive agencies weak ; and as one or the other of these preponderates, so are the organisms killed and infection prevented, or the parasitic organisms prevail and make good DISEASES OF THE SOLDIER. 651 their position in the body. In the military service, the privations, hard- ships and fatigue incident to campaign, and especially the imhealthfulness of localities in which troops may be required to serve, do much to render the organism especially susceptible to invasion by pathogenic bacteria ; but unless such bacteria be actually present, even under such conditions no infectious disease can result. Should, however, the specific bacteria be introduced, and should the essential external conditions of heat, moisture and decomposing organic matter be present for their development outside the body, all the conditions for a violent and sudden epidemic outbreak are at hand. These are further favored by the density of population and community of living which can scarcely be avoided in the military service — both of these factors directly favoring the dissemination of pathogenic bacteria among large num- bers of men and very probably increasing their virulence. The principal and origiual sources of infection in the transmission of infectious disease are the secretions of the sick, the air respired by them, and the dead body. Articles contaminated by^ontact with -the above and harbor- ing the specific pathogenic agent, such as clothing, bedding or the water in which they are washed, are merely mediate carriers of the infection. Por the military service, all epidemics may be regarded as developing from an infection introduced from outside. Bearing these facts in mind, the prevention or control of infectious disease will be more readily accomplished by the sanitary officer. Cbrebeo-Spinal Meningitis. Occurrence. — No great epidemics of this disease .appear to have oc- curred among troops, but the affection is one which prevails in all armies and is remarkable for the high mortality given by those affected. Sharp but distinctly localised outbreaks occur annually in all the larger armies, and in om- own service cases of the disease were reported in all but six years of the period 1868-98. The affection may fairly be regarded as a camp disease; more deaths occurring in our army in the calendar year 1898 than had occurred altogether in the previous sixteen years of peace. For the period 1868-84, the death rate from this disease was .05 per thousand strength; for the decade 1885-94 it was .02 per thousand, while for the fourteen months. May, 1898, to July, 1899, the death rate was .70 per thousand. In the German army, during time of peace, the admission rates are much lower than our own under similar conditions, being given as follows : „„ .„^ Admissions per P''"'"^- 1,000 stren^h. 1881-82 to 1885-86 0.03 1886-87 to 1890-91 07 1891-92 to 1895-96 08 1895-96 to 1897-98 07 Among our own troops the admission rates, per thousand strength, were .11 for the period 1885-94. In 1898 cerebro-spinal meningitis was the greatest factor in the total mortality of the Belgian army, giving a death rate of .35 per thousand. Cause. ^ — The cause of epidemic cerebro-spinal meningitis is now gen- erally regarded as the micrococcus described under the name of diplococcus 652 THEOEY AND PRACTICE OE MILITARY HYGIENE. intracellularis meningitidis. This organism, as its name implies, is found usually in pairs, and located in tiie pus-ceUs of the exudate in much the same way as the gonococcus is located in the pus-cells of gonorrhoea. It is readily detected by microscopical examination of the spinal exudate, ob- tained by lumbar puncture. The organism can be artificially cultivated, but only with difficulty. It grows best on blood serum or nutrient agar ; though occasionally it will not develop in either medium when its presence in the exudate is positively determined by the microscope. It grows only at body temperature. It stains with the ordinary aniliiie dyes, but is de- colorized by Gram' s method. It is very virulent when injected into animals. On drying it is destroyed in one to three days, according to circumstances. Predisposing Causes. — The dis- ease is most common in individuals of the military age. Though want, privation and poor ventilation usually seem to predispose to the disease, there is abundant evidence to demonstrate that these conditions are not • essential to its causation. The disease usually occurs during winter and early spring, although it may make its appearance FIG. 325.-Dipiococcus of Meningitis. at any time. For the period from May, 1898, to July, 1899, the death rate from this disease was .13 per thousand strength in January; beiag about twice as high as any other month of the period. For December it was .07 ; for June and July, 1898, it was .06 and .05 respectively. Hirsch, Notter and Firth and others state that cerebro-spinal meningitis is imknown ia the tropics. " During the period' of fourteen months just mentioned, how- ever, the death rate from this cause was .71 per thousand strength for troops serving in the United States; .34 for troops serving in Cuba; .16 for those in Porto Eico and .26 for those in the Pacific islands. An epidemic of a most fatal type occured on an army transport at Casilda, in southern Cuba, during the occupation of that island by our forces. Of those attacked, all died within thirty-six hours. The epidemic was abruptly terminated by sending the command ashore. For the year 1899 the admission and death rates for this disease among troops serving in the tropical islands were .40 and .25 respectively ; for troops serving in the United States during the same period the admissions were .90 and the deaths .60 per thousand strength. Infection and Dissemination. — It is difficult to offer any satisfactory explanation as to the manner in which infection occurs in this disease, or to the way in which the specific micro-organism is eliminated from the affected individual. Whether it enters the body through the alimentary or respiratory tract or through lesions of the integument, it is not possible to say. It is probably directly communicable from the sick in a mild degree only, but there is considerable evidence to show that the infection may be introduced into a locality by infected persons and things. Abbott and others are in- clined to the belief that cases occurring during an epidemic are infected from some common source, and that they are predisposed to such affection DISEASES OF THE SOLDIEE. 653 by some iinusual local condition. This opinion is supported by the fact that the disease shows no special tendency to progress along continuous lines or through contiguous localities. It has been known to appear in two regiments in a camp, while a third, located between the infected organ- izations, escaped. Love states that at New Orleans, in 1847, the disease attacked one regiment, which was quartered in poor barracks located on a damp soil and was supplied with poor clothing, while an adjacent regi- ment, more favorably housed and clothed, escaped entirely. Depressing influences, whatever their nature, appear to be a predisposiug cause. Prophylaxis. — With present defective knowledge concerning the manner of infection and dissemination of the causative agent in this dis- ease, it is difficult to formulate any rational scheme of prophylaxis against it. While the isolation of the sick has not been shown to be imperative, still this precaution should probably be always taken in the military service. As with typhus and measles, free ventilation shoiild be assured and no con- siderable aggregation of the sick under one roof should be allowed. As a not unreasonable precaution, all discharges and excreta should be promptly disinfected and accidental inoculation on the part of the attendants guarded against. As far as the troops are concerned, free ventilation, sufficient clothing, an abundance of good food and the avoidance of excessive fatigue should be included ia the scheme of general prophylaxis. Cholera. Occurrence. — The military history of Asiatic cholera appears to begin with the year 1757, when the British troops in India suffered greatly from its attacks. It is said that one division of 5,000 men had 500 deaths from cholera in a single day. In 1817, according to Eosse, in a force under Hastings the onset was so sudden that sentries fell as if struck by light- ning and it required three or four men to stand a tour of guard duty of two hours; in five days there were 5,000 deaths, and the command was almost destroyed. In 1821, cholera made such ravages in the armies of Turkey and Persia that it forced military operations in Mesopotamia to be brought to an end. In the years 1830-31 cholera extended all over Europe and was shortly afterward brought to this country ; troops being attacked at a number of stations. At Fort Dearborn, on the present site of Chicago, it is stated by Eosse that 200 men out of a garrison of 1,000 were ad- mitted to hospital with cholera in the course of seven days. During the Crimean War there were 7,375 cases of cholera in the British army, with 4,513 deaths; in the French army there were 12,258 cases, with 6,013 deaths. Among the French troops composing the Dobrutschka expedition it is said that at one time no less than 10,000 men lay dead or struck down by cholera. Out of one battalion, besides those already dead, 500 soldiers affected with cholera were carried in the wagons. Coustan states that in one division of 10,590 men participating in this expedition there were 2,036 deaths. In 1866, during the war between Austria and Prussia, more deaths occurred from cholera, in the armies of the latter country, than resulted from the casualties of battle. At the close of the Civil War our troops suffered severely from this disease; there being, in 1866, 2,813 cases 654 THEORY AND PRACTICE OF MILITARY HYGIENE. and 1,269 deaths. In 1867 there were 504 cases and 230 deaths, and in 1868 there were 7 cases and 3 deaths. Cholera almost destroyed a body of recruits marching from Leavenworth to Fort Hayes, in Kansas, and was also epidemic at Fort Eiley and other stations during this period ; being carried by recruits from New York to California, Louisiana, Texas and Georgia. In 1866 it also broke out in Brazil and the Argentine and was carried by the armies into Paraguay. In the outbreak of 1873 our army was little affected, there occurring but 12 cases with 8 deaths, and since that year there have been no further deaths from this cause in our service. The French army has suffered with the civil population diiring the various outbreaks of cholera in France and Algeria. Eosse states that in Paris, for the period 1832-49, and again for 1853, the mortality amounted to 14.76 per thousand among the civil population and 42.59 per thousand among the garrison troops. In many later instances, how- ever, especially in the outbreaks of 1884 and 1893, the greater care as to sanitary conditions in the French military service preserved the soldiers, while deaths occurred in the surrounding civil population. In the British army, during the decade 1888-97, cholera occurred among troops in India, Egypt, China and Ceylon. In India, for this decade, the admission rate per thousand was 1.8; the death rate 1.29. Cholera figures almost annu- ally in the returns for the Eussian army, certain military garrisons of which are located in regions where the disease prevails endemicaUy. Ee- cent figures for cliolera in the Eussian army are as follows : Year. Admissions per 1,000 strength. Deaths per 1,000 strength. Year. Admissions per 1,000 strength. Deaths per 1,000 strength. 1890 1891 1893 1893 0.06 4.3 1.61 0.03 1.83 .46 1894 1895 1896 1.00 .40 .01 0.35 .10 .003 Cause. — Cholera results from an invasion of the body by the specific micro-organism of the disease. The spirillum or comma bacillus is a curved or spiral organism, occurring most frequently in the form of a short, comma-shaped rod. The curving of the rod varies, being very marked in some individuals and absent in others. In cultures some days old, de- generated and atypical forms are found. The organism is motile, and a single flageUum is attached to the end of the rod. The microbe does not form spores nor cause fermentation of glucose or lactose. It liquefies gelatin and produces iudol. Litmus milk is turned red and is coagulated by it. It does not staiu by Gram's method. Freezing does not destroy its vitality, but drying destroys it in a few hours. When in a moist con- dition it retains its vitality for many months. Woodhead has pointed out that when grown ana6robically the bacillus gains greatly in virulence but largely loses its power of resistance to germicidal agents; conversely, when grown aerobically, it largely loses its virulence but gains in resisting power. Comma bacilli are only feebly resistant to acid solutions ; a fact which explains the greater susceptibility to this disease of individuals affected with digestive disorders. In stab cultures, growth occurs all along the line of inoculation, with liquefaction at the surface in forty-eight hours. The liquefaction proceeds in such a manner that the liquefied area has a smaller DISEASES OE THE SOLDIER. 665 ■diameter at the surface than immediately beneath, and owing to' the fact that the Liquefied gelatin does not fill the cavity, a space is left between the surface of the medium and the surface of the liquefied gelatin, so that the appearance of an air-bubble is produced.' On gelatin plates the largest colonies, after incubation for twenty-four to forty-eight hours at 20°-22° C, appear as masses of indefinite granxilar material lying in circular areas of liquefied gelatin, in which granular shreds are scattered. Within the next twenty-four hours the areas of liquefaction increase, and the colonies appear under the low power as a dense granular mass surrounded by an area of liquefaction through which can be seen gianular prolongations of the colony, usually extending irregu- larly between the periphery and the central mass. While in form and methods of growth the comma bacillus is resembled by another group of special organisms, it is safe to assume, during the preva- lence of Asiatic cholera, that indivi- duals presenting comma bacilli in their intestinal discharges are affected with this disease. The most important di- agnostic tests for this organism depend, according to Muir and Eitchie, upon its failure to infect pigeons when a RTnall ■nnrtion of a snliH ciiltnrp of it, is ^lO- 326.— Bacilli of Asiatic Cholera, showing smau portion oi a bOliu omtuie oi lu IS Ha^ella. (After Mallory ana Wright.) introduced into the pectoral muscle; and also the loss of motility and clumping of the cholera bacOi which fol- lows upon their contact with the serum of animals artificially immuni2;ed to Asiatic cholera. The effect of introducing cholera bacilli into the peri- toneal cavity of the guinea-pig is discussed later in connection with the preparation of prophylactic fluids. Dissemination and Infection. — The specific causative agency in cholera is given off chiefly from the bowels, and to a less degree in the Tomitus. The length of time during which the stools of a cholera patient are infectious is unknown, but it probably is a considerable period. As with typhoid fever, apparently healthy persons appear at times, during an epidemic, to act as hosts for the bacilli and play a part in the propagation of the disease. While the disease sometimes foUows contact with the sick, it may fairly be regarded as only slightly contagious and not likely to be contracted except by indirect infection. The latter undoubtedly occurs by way of the alimentary tract. There is no proof that air ever serves as the vehicle for the transmission of cholera' baciUi; though in this disease, as in typhoid fever, its dissemination by this means should be regarded as possible. Water has long been recognized as the chief agent in the spread of cholera; and abundant circumstantial evidence to this effect is fortified by a number of instances in which the specific etiological factor has been discovered in water by bacteriological investigation. Many instances have been reported in which the infection of a water-sup- ply was followed by outbreaks in communities further down the stream. In the epidemic at Hamburg, in 1892, the part played by an infected 656 THEOEY AND PEACTICE OF MILITAEY HYGIENE. water-supply was most marked ; the proportionate nimiber of cases being eight times greater in that part of the city in which unfiltered water was supplied than in the part in which the drinking water was partially purified by sand filtration. Eecently, among the British troops at Umballa, in India, an epidemic of cholera promptly ceased as soon as a supply of steril- ized water was provided for drinking purposes. Cholera bacilli flourish best in sluggish streams, and especially in water containing a considerable proportion of organic matter. Under certain circumstances, not as yet fuUy imderstood, the baciUus is capable of rapid multiplication in water, but many saprophytic micro-organisms are hostile to its development and appear to destroy its vitality in the course of a few hours or days. Any con- tamination of this specific character, however small, is capable at times of im- parting to enormous quantities of water the power of originating the disease. Damp earth undoubtedly serves at times as a medium for the development of the bacillus outside the human body. At Luoknow, 90 soldiers out of 600 died apparently as a result of placing fresh sand, taken from the bank of a river used as a general bathing place, in a filter from which water was drawn for the use of the command. Food, contaminated by cholera dis- charges, also serves as an agent for the spread of the disease. This is rarely directly infected, but is contaminated by manipulation with unclean hands, by contact with infected objects, by dust containing the specific germs or by the agency of flies which have recently fed on cholera discharges. In India, medical officers now regard the latter as one of the more com- mon agencies by which the spread of cholera is accomplished. In the Burdwan prison, where other means of infection were scarcely possible, it is said by Buchanan that a recent epidemic was directly traceable to flies which were carried over the prison wall by a high wind blowing from the direc- tion of some native houses, in which the disease had occurred. Diuing the outbreak in the Gaya jail, Macrae found that milk to which flies in the jail were given access invariably became infected with comma bacilli ; and he concluded that "flies should be looked on in the light of poisonous agencies of the worst kind during cholera epidemics." The cholera bacilli may be carried in fomites, particularly in rags or clothing soiled with the faecal discharges of the sick. Under such conditions they retain their vitality for considerable periods, though they are readily destroyed by sunlight and desiccation. As with typhoid fever, the disease germs may be carried into camp or barracks on the shoes of individuals who have visited an infected latrine or locality. Marching troops, when infected, do much to spread the disease through districts in which it may have been previously unknown. The period of incubation of cholera is usually about three days, but this, under rare circumistances, may extend to as much as ten days. Predisposing Causes. — Cholera prevails endemically in certain parts of India, from which it extends from time to time. It appears to be a settled fact that where the disease prevails in an endemic form it does not occur in great epidemics. A severe outbreak appears to confer upon the locality attacked a more or less complete immunity; the durability of which, so far as India is concerned, appears to last for a number of years. A high temperature is a predisposing cause of great importance ; but while many epidemics have ceased with the advent of cold weather, this is by no DISEASES OF THE SOLDIER. 657 means always the case. In the tropics, cholera prevails to the greatest extent toward the close of the dry season. A moderate raiufaH tends to cause the further development of the disease, but when the rains are heavy and continued a marked diminution in the occurrence of cholera is con- stantly observed. There is a general consensus of opinion that the in- cidence and severity of the disease are greater among negroes than among whites. In the United States army, during the epidemic at the end of 1866, the mortality among the white troops was 77 per thousand, while among the colored troops it was 135 per thousand. Where the disease prevails en- demically, the native population appears to enjoy a considerable but not absolute immunity to it. In the Hedjaz and in the sparsely populated parts of Arabia, it is said by Fauvel that the disease manifests only a feeble tendency to propagate itself among the native population. This immunity, however, is not shared by strangers visitiag a locality endemically affected. As a race, the Chinese appear to be notably free from the ravages of cholera, probably largely from their use of sterilized water in tea. In any outbreak of this disease, numbers escape attack through their hereditary or gradually acquired powers of resistance. For epidemics of cholera a stratum of moist soU pervious to air, in which organic material is decomposing, affords the most favorable condition. General sanitary defects, by which the specific fouling of soil and water is possible, are essential to the development of an epidemic, and it has long been observed that the poorer quarters of a com- munity suffer far more during a cholera visitation. Epidemics, also, pre- vail more severely in low-lying regions than on high groimd. Insufficient, poor or coarse food, improper clothing and inadequate shelter favor the occurrence of cholera; .and physical and mental depression are both mark- edly predisposing causes. Overcrowding is also a factor of importance. Those who are affected with catarrh of the intestinal tract and diseases of the digestive apparatus are particularly susceptible to cholera infection. Prophylaxis. — In view of the fact that in practically every instance of an outbreak of cholera, in regions or communities in which it is not endemic, its origin has been traced to importation from abroad, it is mani- fest that where practicable a system of quarantine should be established as soon as the danger of an introduction of the infection is recognized. No person jfrom the infected locality should be admitted within the military lines without imdergoing examination and being held under observation for a period of ten days. All clothing and similar articles should be dis- infected before being passed; supplies intended for food, unless carried through the affected district in imbroken packages, should not be admitted. Special cholera hospitals, in readiness for an outbreak, should 'be established and provided with a special staff of attendants. They should not be located at too great a distance from the main body of troops, from the rapid nature of the disease. Such hospitals should possess separate facilities for the isolation and treatment of suspects as well as clearly defined cases of cholera. If the disease appears to be spreading and the camp or post is not in good sanitary condition, its abandonment by troops is indicated. When the disease prevails, all persons suffering from diarrhoea, no matter how insignificant the affection may appear, should be regarded as suspicious and should be subjected to the same vigilant supervision as applies to genuine cholera patients — for many of these cases, though mild as regards 42 658 THEORY AND PRACTICE OE MILITARY HYGIENE. the affected individuals, are nevertheless those of true cholera and are capable of disseminating this disease. Because of their apparently innocent nature these cases often escape the attention their importance demands ; and un- less it be borne in mind that they are a grave menace to all with whom they are associated, and are treated as such, they can only be regarded as most dangerous sources for the dissemination of disease — far more so than the severe cases which attract attention from the outset. To this end, frequent inspections of latrines should be made and the character of the discharges noted. Convalescents from cholera ■should be kept isolated, and the evacuations from the bowels should be constantly disinfected until bacteriological examination demonstrates that the specific micro-organism causing the disease has disappeared from the discharges. Such individuals should be returned to their respective organizations only after a disinfect- ing bath and after donning a complete outfit of clothing sterilized through- out. The antecedents of each case of cholera should be investigated, and all those who have been in immediate association with the patient should be placed under observation. Every effort should be taken to locate the probable source of infection. As cholera germs can live and multiply for a time, outside the body, in the presence of decomposing organic material, more particularly that of animal matter, there should be a thorough removal of every sort of filth and refuse from the camp or garrison. Thorough cleansing, airing, paint- ing and Hmeiwashing should be carried out wherever indicated. It should not be forgotten that, although desirable at all times, measures of cleanli- ness taken in advance are of far more value for protection against cholera than policing delayed until after the disease has actually made its appear- ance. The water used for drinking purposes should invariably be sterihzed ; preferably by heat and best by the Forbes-Waterhouse apparatus. Under all circumstances, in time of cholera, an immediate and searching examina- tion of the sources and conduits of the water-supply should be made, when ,it is in any way open to the suspicion of impurity. Where pollution is found to have occurred, every care should be taken to prevent such pollu- tion from continuing and the water from being utilized. Where the water supply is believed to be at fault, washing of the person, except with boiled water, should be prevented as far as possible. For marching troops, great care should be taken to prevent the use of water from infected towns. Tea has been much used by British troops in India during cholera outbreaks, as being more jjalatable than ordinary boiled water. Acidulated drinks con- taining sulphuric acid, acetic or citric acid may sometimes be given with ad- vantage. Eeli wine is also recognized as destructive to the cholera bacillus ; and a ration of this, taken diluted in water, might well be issued during an epidemic. The use of alcoholics generally, as interfering with digestion, should be avoided. The food supplied should be abundant, simply prepared and readily digestible. Intemperance in eating, however, is quite as bad as intemperance in drinking. Particular care should be taken to ensure the condemnation and rejection of any food of unsound or indigestible character capable of exciting a diarrhoea. With the exception of acid fruits protected by an outer rind, such as oranges and lemons, no article of food should be eaten that has not been subjected to a boiling temperat\ue in its prepara- tion. Under no circumstances should the use of uncooked vegetables or DISEASES OF THE SOLDIER. 659 salads be permitted. All food and drink should be carefully protected against access by flies, since some of these may have previously come in contact with cholera discharges. Prior to use, all vessels employed for the cooking, serving or storiag of food should be sterilized by immersion in boiling water. The purchase of food- or drink by the men at points outside of military control should be prohibited. The hands should be washed before eating. Troops should be weU clothed, sufficiently to protect against cold, chilling and moisture; it is during outbreaks of intestinal disorders of this character that the use of the abdominal band is of most advantage. The clothing should be frequently changed, washed and simned. There should be no unnecessary exposure to sun, rain or night air ; and no drnis or fatigue other than to furnish occupation and needful exercise. The size of the guard and the length of the tours of duty should be reduced as much as military conditions permit. In addition to fatigue, nothing is more conducive to the spread of the disease than fear and unusual excite- ment, and a quiescent state of mind should be enjoined upon all. In general, the troops should be regarded as engaged in campaign against an insidious and implacable enemy, and the attention of every officer should be devoted to superintending the conduct of his subordinates with special reference to this view. In time of impending epidemic, troops should be scattered. A change of soil and locality often appears to be of advantage and camps should be moved as often as cases appear. Troops that have fallen back before the advance of the disease have often escaped seizure, or have avoided further sickness if withdrawn subsequent to the time of their attack. A temporary abandonment of an infected locality is strongly to be recommended. When the disease has actually occurred, efforts at disinfection should be primarily directed toward the vomitus and fsecal matter. These should, as far as possible, be burned. If the cases occur on board ship, the excreta should be received in vessels and disinfected. They should not be discharged overboard, particularly if in harbor or on fresh water, but should be de- stroyed by fire. The disinfection to be practiced includes that of the bar- racks, tents or places occupied by the sick, and the articles of clothiag and bedding with which they may have come in contact — and upon its prompt- ness and thoroughness, together with isolation of all those attacked by cholera and their attendants, depends the arrest of the epidemic. If due care in regard to cleanliness and disinfection be observed, there is compara- tively small risk that the disease wiU. spread to those who nurse or other- wise attend upon the sick. Frequent baths on the part of the attendants, with disinfection of the hands after each manipulation of the patient, should be required. Preventive Inoculation. — ^As a method of prophylaxis against cholera, inoculations with specially prepared virus have been systematized and suc- cessfully practiced in India by Haffkine. The method gives an immunity to the living microbe, preventing it from surviving after entering the system and thus causing an attack of the disease. If, however, the specific bacillus once succeeds in establishing itself, the inoculation appears to have no influence upon the symptoms of the disease, as produced by the toxines resulting from its growth and development. The method depends upon the immunizing of the patient by accustoming the system of the individual to the 660 THEOEY AND PEACTICE OF MILITARY HYGIENE. specific organism by the injection, first, of a weak, and later, of a virulent culture. By some, small and large doses of a virulent culture are preferred. As the cholera bacilli found in dead cholera cases vary greatly in ap- pearance and virulence, Haffkine advises that only the most typical speci- mens be employed in the preparation of the prophylactic fluid. This is done as follows : A pure culture, grown on agar, is emulsified with a s^iall amount of sterilised water. The emulsion is then drawn iato a suitable pipette and iojected into the peritoneal cavity of a guinea-pig, previously prepared by an assistant by shaviag and searing the abdomen. The ani- mal usually dies in twenty-four to forty-eight hours after the inoculation, and tlie peritoneal exudate is found to contain comma bacilli of greatly increased virulence. This exudate is then passed into the peritoneal cavity of another guinea-pig, and the process is repeated until the microbe reaches its maximum virulence, when a healthy guinea-pig, weighing about 375 gm., will be killed in about eight hours. Between each inoculation into the guinea-pigs, the exudate should be stored in a dark place for fourteen to sixteen hours, since if this be not done the microbes soon lose their virulence and die out. The exudation, where the baciUi are vigorous, is clear and transparent and of a reddish color. It varies greatly in quantity, ranging from six or seven cubic centimeters to a few drops. In general, the larger and more resistant the guinea-pig inoculated, or the weaker the virus or the smaller the injected dose, the larger will be the quantity of the fluid — and vice versa. Large quantities of exudate contain proportion- ally few microbes. Agar tubes inoculated with virulent peritoneal exudate are now incu- bated for twelve to twenty-four hours at 37° C. A free growth is obtained by passing the point of a small glass brush, carrying a growth obtained from a culture of the peritoneal exudate, over the agar slant until the sur- face is evenly infected. After incubation and an examination to ensure that no contamination by other micro-organisms has occurred, sterilized water is poured into each tube. Usually, for growths made in twenty-four hours, the water should reach one-third the way up the agar slant. The tube is then rolled between the fingers until the bacilli have been soaked off into the water. The emulsions should be protected against simlight, or a strong diffuse light, and should be used within an hour. The inocu- lation is made under antiseptic precautions, usually in the flank. Hare makes the following remarks as to the dose : " A standard bacteriological tube is 16 cm. long and 1^ cm. broad, and is fiUed to two-thirds of its height with agar mixture. Such tubes, with a culture of comma baciHL of the fuU strength after twenty-four hours' growth at the temperature of the body, may be taken as a unit ; and when filled with water up to one-third the height of the agar, each tube wiU. give a definite quantity of vaccine of a standard strength. The dose of such vaccine for an adtilt is half a cubic centimeter. To decide the dose of the second injection the operator must rely exclusively on the amount of fever produced by the first. The average height to which it rises after a full dose is I02°-103° F., ten to twelve hours after the operation ; in such cases a fuU dose of the second vaccine may be given; but in exceptional cases where the fever reaches 104° F., or over, give only two-thirds of the fuU dose, and when the fever stops be- low 101° F., give in excess of the full dose." DISEASES OF THE SOLDIEE. 661 In some instances the bacilli are kOled before injection by the addition of dilute carbolic acid, but living microbes are ordinarily employed. Ac- cording to Cantlie, the bacOli die immediately after the fluid is injected subcutaneously, and hence the choice of either form seems immaterial. Other observers believe that the immunity conferred by living organisms is of longer duration than where the dead bacilli, or the products of their cultures, are employed. The method of inoculation, when proper care is taken in the preparation of the anti-microbic fluid and in its administra- tion, appears to be quite devoid of danger. In speaking of the reaction which follows such inoculation, Simpson says : " There is a certain discom- fort produced by the inoculation, such as an attack of fever lasting about twenty -four hours, pain at the seat of inoculation on moving, thus interfer- ing with physical work for about thirty-six hours. The discomfort, how- ever, is not worse than that induced by vaccination, when the vesicles have risen weU, and has the advantage of not lasting nearly as long." The protection conferred seems to be marked at the end of four days, and during this period the difference in susceptibility to cholera is in favor of the inoculated. The duration of the immunity acquired has been shown to exist for at least fourteen months. Simpson states that the blood sera of individuals after inoculation have a destructive effect on cholera baciUi which is more than two hundred times greater than that of the sera of unprotected persons. A large number of individuals — upward of 100,000 — ^have been inocu- lated by Haffkine, in India, against cholera; among them a number of white and native soldiers in the British service. While the results have varied greatly, they are on the whole distinctly favorable. Among 1,526 non-inoculated soldiers at Dinapore and Cawnpore there were 25 cases, while among the 268 inoculated there were no cases. In Calcutta, from the 10th to the 459th day after inoculation, cholera visited 26 houses. Among the 263 uninoculated inmates there were 14.45 per cent, attacked, while among the 137 inoculated the proportion attacked was only .75 per cent. The East Lancashire regiment received weak protective inoculations. Some months later it was exposed to cholera, and the small death rate showed the prophylactic value of the inoculation. According to Simpson, 654 in- dividuals not protected against cholera had, during a period of two years, a mortality of 10.86 per cent.; while of 402 members of the same house- holds, inoculated by him, the mortality from cholera during the same period was but 2.99 per cent. While prophylactic inoculation against cholera is still under trial, it may fairly be assumed that a means of pre- vention of much value has been discovered. Dengue. While dengue is not a disease which appears to be in any way affected by the conditions of military service, our troops have suffered equally with the surrounding civil population during the epidemics which have from time to time occurred. Since this affection is confined to tropical and sub-tropical countries, the only posts in this country which have been visited are those located in the south and southwest. During 1893 the affection prevailed in several garrisons. In 1894 the disease occurred at 662 THEORY AJsTD PRACTICE OF MILITARY HYGIENE. Fort Ringgold, attacking 154 men out of the 178 stationed at that post. In 1897 dengue appeared at Fort Sam Houston; 144 cases developing out of a total strength of 522, and over 100 cases being treated among the families of soldiers and civilians at the post. During the same year the garrison at Fort Mcintosh also suffered. Eecently a large number of cases of this disease have occurred among our troops ia Cuba and in the Philip- pine Islands. The cause of dengue is unknown. The outbreak of the disease is favored by high temperature and geographical location more than any other factors; occurring chiefly during summer and early autumn and being checked- by frost. In its distribution, dengue closely resembles yeUow fever. Overcrowding and filth appear to favor its occurrence. The mor- tality is small, and for soldiers otherwise in good health may be regarded as nil. ' The disease, therefore, is of importance only as it incapacitates for duty. The specific cause of the disease is supposed to be given off in the saliva and excretions, and perhaps from the skin. Its incubation period is only a few hours, a fact which may explain its almost simultaneous appearance in large bodies of men. Prophylaxis. — In the lack of knowledge as to the cause of this disease or the means of spreading it, it is not possible to formulate definite plans for its prevention. Since the ubiquity of the virus is so great in this disease, the establishment of quarantine would scarcely be effective even if it were justifiable. The isolation of the sick, with the disinfection of aU ex- creta, clothing and surroundings, might be practiced, but would probably not be of any great value in checking an epidemic. It is fortunate that the disease is mild in type, is of short duration and leaves no after-effects — thus being of comparatively little importance to the military sanitarian. DiAKEHCEA AND DiAEEHCEAL DISEASE. Diarrhoea is ordinarily to be regarded not as an essential disease but as symptomatic of some morbid internal condition or of an effort on the part of the healthy bowel to relieve itself of irritating contents. In the mili- tary service, however, the affection frequently prevails among a large number of soldiers at the same time and place, and by its severity, its tendency to become chronic, its refractability to treatment and its un- doubtedly, infectious character it may, under such conditions, be safely re- garded as a distinct disease. Figures showing the prevalence of this specific affection are not available for our service, owing to the classification of all diarrhoeas, whether symptomatic or essential, under the same head- ing. Further, in the medical reports of our army, conditions of this char- acter, together with dysentery, are classed together as diarrhoeal disease and hence must be largely considered in relation to each other. Diarrhoeal diseases produce a large amount of inefficiency and during the decade 1887-96 brought more men on sick report than any other class of affections, the rate per thousand strength being 107.09. Field service largely favors their occurrence, and in nearly all wars they have been the most common class of affections occurring among troops. For the year of peace 1897, the admission rate in our army for all diarrhoeal diseases was 73.77 and the death rate zero; while during the year of war, 1898, the admission DISEASES OF THE SOLDIEE. 663 rate was 303.76 and the death rate 2.14. These diseases are much more prevalent in hot climates than in the temperate zone, the admissions and deaths for troops in the United States alone, during the year 1898, being respectively 247.39 and 1.39 per thousand strength; while for those serv- ing in the tropical islands the admissions were 551.54 per thousand, and the deaths 5.44. For diarrhoea alone, the average annual rate of admission was 608.84, per thousand strength, during the Civil War ; while the deaths from this cause averaged 13.70 per thousand. For the period 1868-84 the ad- missions for diarrhoea were reduced to 230.45, and the deaths to .26, per thousand strength. For the decade 1885—94 the admission rate was 109.65 and the death rate .02. For the year 1897 the admissions per thousand amounted to but 68.65, there being no deaths. For the year ^ntJ^^aTV. Sfir. Jian Jipril J(o.y J-u-ni Ju-ly ^. S,-/,. 0oi. Mr. >5». ~JS3- - .„, _ -JJ.- _ - -i4. 2! I if ~iS- i\ -u- -it- -.'it :%■■ - IT- -/*• - /J- - n- - II- - ^^ ^^m - ^ ^H E ^ ^H* 1 = 1 E 1 -'l - 1- -.i- - i- - * - / _ Fig. 327.— Chart Showing the Monthly Distribution of Cases of Diarrhoeal Disease, per Thousand Strength, Occurring during the Decade 1875-84, In the United States Army. 1898, during the war with Spain, the admission rate rose to 274.49, but the death rate amounted to only .27 per thousand strength. Diarrhoeal diseases, in the temperate zone, are much more prevalent during hot weather, as is well shown by the accompanying diagram. Eace is a matter of no small' importance. While the colored troops are particularly susceptible to infection by dysentery, this is not the case with regard to simple diarrhoea, to which they appear to present a certain im- munity. For the decade of peace 1886-95, the admissions per thousand of white troops, for all diarrhoeal diseases, amounted to 115.68; while for the colored troops during the same period the rate was 99.75. For the year 1897 the rates of admission were 75.78 for white troops and 52.22 for colored soldiers. Durkig the war with Spain a proportionally much greater number of negro soldiers saw hard service than did those of the white regiments, yet the admissions for the former were only 187.20 per thousand strength, while they amounted to 312.72 per thousand of the latter. Age 664 THEORY AND PEACTICE OF MILITARY HYGIENE. exerts a marked influence on the occurrence of diarrhoeal diseases ; the rates for our service, at various periods of life, averaged for the seven years 1890-96, being as follows: . „. Admissions per -^-se- 1^000 of each class. 19 years and under 202.43 20 to 34 inclusive 134.19 35 to 29 " 98.70 30 to 34 " 83.00 35 to 39 " 79.00 40 to 44 " 80.96 45 to 49 " 75.68 For the same seven-year period the admission rates for all diarrhoeal diseases, per thousand strength, were thus divided among various branches of the service : Artillery 133.35 Cavalry , 113.29 Infantry 96.84 Medical Department 34.96 Diarrhoeal diseases are much less frequent among officers than among soldiers. As stated above, in many instances diarrhoea is undoubtedly infectious and capable of transmission to others by means of the excreta. No special micro-organism has been shown to stand alone in a causative relationship to the disease, and the latter may probably be produced by several forms of bacterial life. Diarrhoea prevails most ia damp soils, especially when contaminated with organic matter. The diarrhoea prevalence and death rate are notoriously greatest among those whose resistive powers are im- paired by malnutrition, exposure and fatigue. As with dysentery, chill- ing and sudden changes of temperature appear as predisposing factors. Foul air favors it, and want of ventilation and light are conducive to a high mortality. Density of population, especially as a factor ia the soil pollution of camps, markedly increases the prevalence of diarrhoea. Food is closely concerned with the epidemic prevalence of diarrhoea ; not only by predisposing toward it through the production of digestive disorders, but also by its contamination with infectious material capable of directly provoking the disease. Bad water undoubtedly plays a prominent part, but prob- ably not to the extent supposed by some. The cause of epidemic diarrhoea is undoubtedly transmissible by means of flies, and there is considerable evidence to show that air-currents may be the means of its dissemination. A distinction should be made between the epidemic diarrhoea indicated by the foregoing and those outbreaks of diarrhoea which not rarely occur among troops who have partaken of food in which certain putrefactive changes have occurred. In these cases the causative agent is usually a chemical substance and the diarrhoeal symptoms produced are merely those due to the properties of the latter as an irritant poison. Prophylaxis. — The prevention of epidemic diarrhoea depends upon the proper location of the camp, the absence of organic pollution of the soil, a pure water supply, the careful selection, preparation and storage of food, and the prompt disinfection of all excretal discharges in camps of any permanency. While mild cases, in garrison, may be safely treated in quarters DISEASES OE THE SOLDIEK. 665 under most circumstances, in the field, where their infectious nature is suspected, such cases should preferably be removed to hospital for treat- ment — ^particularly since cases of apparent simple diarrhoea may often represent the early stages of iafection with dysentery, typhoid fever or cholera. From the many causes by which diarrhoea may be produced, it is evident that no general rules of prophylaxis can be laid down to cover aU contingencies, but each instance must be acted on independently, according to its merits, by medical officers. Diphtheria. Occurrence. — Diphtheria is a disease which is of somewhat rare oc- currence among soldiers. It is less common during active field service than in garrison, where it not rarely retains a foothold in old badly con- structed barracks for long periods, yearly outbreaks occurring during cold weather. The disease is relatively frequent among troops living in case- mates. At Fort Yates it occurred annually for a number of years, despite every effort toward its prevention, among soldiers quartered ia old decayed log barracks ; while troops living in barracks of recent and more sanitary construction at the same post were scarcely affected. This tenacity of the diphtheria infection, in old buildings or those with defective plumbing, has often been noted. Figures for this disease show a somewhat lessened prevalence in our army as compared with those of England, France and Eussia. In the Ger- man army the admissions for diphtheria, per thousand strength, have been as follows : Period. Admissions. 1881-82 to 1885-86 1.3 1886-87 to 1890-91 92 1891-92 to 1895-96 93 Year 1896-97 57 In the Austrian army, for the year 1897, only one case occurred for each ten thousand men. For our own service, statistics would seem to show that the disease has of late years decreased in both frequency and virulence. Whether this is actually the case, or whether the reduction merely depends upon more accurate modern methods of diagnosis and treatment, is a ques- tion which cannot be definitely decided — but it is probable that both fac- tors should be taken into consideration. During recent years, however, according to Coustan and Viry, the disease has steadily increased in the French army. In our own service the admissions for diphtheria since 1860, per thousand strength, have been as follows: Period. Admissions. 1861-66 (Civil War) 3.39 1868-84 55 1885-94 43 1895-98 78 Year 1897 43 Year 1898 (Spanish War) '...'. .'. M Cause. — Diphtheria is caused by a specific micro-organism, the bacil- lus diphtherias. In morphology, the bacOIus varies greatly according to the method of its growth. In diphtheritic membrane the bacUli appear as 666 THEOEY AND PEACTICE OF MILITARY HYGIENE. slender rods, straight or slightly curved. Sometimes the ends are swollen or clubbed, but often they are rather tapered off. There is want of uni- formity in the bacilli when compared side by side; and they also stain irregularly, giving a dotted or beaded appearance. They do not form spores or liquefy gelatin, and are not motile. The bacillus grows readily in most of the ordinary nutrient media, especially those of feebly alkaline reaction that can be kept at body temperature. On blood serum, colonies appear within twenty-four hours, often before any other growths are visible. In cultures, the bacilli possess great vitality. At 37° C. they may survive for two months, and at room temperatures even longer. In the moist con- dition they are readily killed at 60° C. in a few minutes; but when dried they can resist a temperature of 98° C. for one hour. In the presence of light or moisture, the bacilli exposed to room temperature die out some- what more rapidly, and in cultures they are destroyed by direct sunlight in one- half to three-quarters of an hour. Dissemination and Infection.^ — The causative agent of the disease is transmitted from the sick in the dis- charges and secretions of the affected surfaces. In diphtheria affecting the throat and fauces, the disease is trans- mitted chiefly ■ through the infected particles of mucus or flecks of mem- brane which may be ejected from the mouth or nose by the act of coughing or sneeziQg. When the disease occurs 7,G 328.-DipMb^en^aB^a.^im^f^^^^^^ (Af- among thoso in attendonce On the sick, its origination is usually brought about by infection in this manner. It has already been noted that the baciLLus of diphtheria is very resistant to drying, and when dislodged fronl the throat ia bits of false membrane it may retain its vitality for a long time. When such particles of membrane are dried and reduced to dust, infection may oc- cur from the inhalation of air ia Which such particulate matter is temporarily suspended. All clothing and other articles which have been in contact with the sick and upon which saliva has been allowed to dry may serve in this way to spread the infection. Abbott states that diphtheria bacilli have been found in the hair and on the shoes of nurses in a diphtheria ward — also on brooms used in the same ward. The bacilli may be inadvertently con- veyed to the mouth after handling infected articles ; and, in fact, any direct or mediate contact with the sick offers opportunities for infection. There is no evidence that the disease is ever transmitted by water. Milk, specifi- cally infected during handling, has been known to give rise to diphtheria. Among the lower animals, cats may be affected with this disease. While the specific baciUi are capable of development on any mucous or abraded surface, for military purposes infection may be considered to occur through the mouth and nose only. The period of incubation is difficult to deter- mine; symptoms of invasion often appear within thirty-six hours after infection, but though they are rarely delayed more than four or five days they may be absent longer, and a quarantine of suspected cases for ten DISEASES OE THE SOLDIER. 667 days is advisable. Convalescents from diphtheria "should be regarded as sources of infection so long as the specific bacilli can be detected in the throat or secretions. The duration of infectivity appears to be, on an average, about thirty days, though it may be as long as three or foiu- months. Predisposing Causes. — Though widely diffused, diphtheria prevails chiefly in temperate and cold, damp climates. Low-lying districts, pos- sessing a soil retentive of moisture and rich in decaying organic matter, usually show a greater prevalence from diphtheria, especially if subject to the continued prevalence of cold winds with a high rainfall. In our ser- vice the disease is far less frequent in the southern garrisons. Its greatest incidence occurs in winter and early spring, probably largely through less free ventilation of barracks and the depressing influence of a vitiated atmosphere. The part long thought to be directly played by sewer gas in the production of diphtheria was imdoubtedly due to accompanying in- fluences of the above nature. Overcrowding is a factor of great importance in the spread of the disease, as is also inadequate sanitary police. Epi- demic diphtheria, according to Klebs and others, has a well-defined rela- tion to manure and compost heaps, in which the germs find favorable con- ditions for development. From this it would seem that the disease should occur more frequently among mounted troops, and such in fact is actually the case. While statistics for our own service are scarcely large enough for reliable comparison, it has been found by Longuet that in the French army, for the period 1872-85, the relative proportion of diphtheria among cavalry and infantry was in the ratio of 10 to 3. In the German army, 1874-82, diphtheria was more than three times as common among cavalry as among infantry. In general, persons who have been affected with diphtheria are especially liable to future attacks, as are those who suffer from acute or chronic inflammations of the pharynx or tonsils. For our own service, it would appear that the colored troops are less susceptible to the diphtheritic infection. Prophylaxis. — In the prevention of diphtheria the provision of dry, sunny, well-aired barracks, free from overcrowding, is important. No accumulation of filth or refuse, and particularly stable manure, should be permitted in the vicinity. Dampness arising from the use of too much water in cleansing floors should be avoided, as often producing a pharyn- geal or tonsillar inflammation upon which a diphtheritic infection may be engrafted. Laveran regards the general use of antiseptic mouth washes as of advantage during the prevalence of the disease. Where the disease has actually occurred, the sick should be at once isolated and all clothing, bedding and other articles which have been exposed to infection promptly removed and disinfected. The squad-room in which the affected individual was quartered should be disinfected. All discharges from the point of diphtheritic invasion should be received into a strong germicidal solution; or on cloths, which are then burned. Soiled bed or body linen should be at once removed and disinfected before the secretions or discharges dry upon them. Where this is not practicable, the soiled areas may be wet with some strong disinfectant solution. The floor should be frequently mopped with a similar solution ; and the hanging of a damp sheet over the door leading into the isolation room is of advantage. Eating utensils should be scalded 668 THEOEY AND PRACTICE OF MILITARY HYGIENE. after use and all uneaten remnants of food at once burned. On the part of the attendants, great care should be taken to disinfect the hands after each manipulation of the patient. WliUe attending to the sick, a cotton mask, suspended so as to shield the nose and mouth and moistened with some antiseptic solution, may be worn to prevent possible infection from ejected mucus or membrane. Careful disinfection of the room and its con- tents is, of course, required after removal of the patient. Protective Inoculation. — In preventing the occurrence of diphthe- ria in those exposed to infection, the most important prophylactic measure is that through which a condition of insusceptibility is conferred by the sub- cutaneous injection of blood-serum from an animal rendered highly immune to this disease. As the immunity thus produced is not permanent, lasting but four to six weeks, the procedure should be employed only in soldiers who have been presumably exposed to infection, or for the protection of such Hospital Corps men as are about to assume charge of diphtheria patients. The method of preparing this protective serum is as follows: Very wide, flat, loosely-stoppered flasks, containing bouillon in a layer of small depth, are inoculated with virulent diphtheria bacilli and incubated at 37° C for about three or four weeks. In order to obtain an active toxin it is desirable that the bacillary growth should take place in the form of a dense white pellicle on the surface of the bouillon. The baciUi are thus brought in contact with a free supply of oxygen, which is necessary for the best results ; and it is important to keep the flask undisturbed after the pellicle has begun to form, in order to avoid breaking up the film of bacUli. The latter are then destroyed by the addition of sufficient tricresol to make a strength of one per cent, and the solution is allowed to stand for several days ; the toxin solution appearing to gain in strength from the substances dis- solved out of the dead bodies of the bacilli. The latter are then removed by filtration through porcelain. Before using the toxin it is standardized, so that the solution of toxin, when injected in the quantity of .01 c.c. into a guinea-pig of 300 gm. weight, will produce death in twenty-four to thirty- six hours. A young, healthy, well-nourished horse, which has been pre- viously tested for glanders and tuberculosis with mallein and tuberculin, and which has been given careful attention in the matter of food, water and sanitary surroundings, is then given a subcutaneous injection of 1 c.c. of the standardized toxin solution. Following the injection of the toxin there are irritability and elevation of temperature, lasting about three days. After a few days of normal temperature a second and somewhat larger dose is given, and the process is repeated with rapidly increasing doses until in from ten to twelve weeks the animal is receiving an injection of 300 c.c. of the toxin solution with impunity. A small amoimt of blood is then withdrawn and the serum tested as to the amount of antitoxin it may con- tain. This is done by simultaneously injecting a guinea-pig with .1 c.c. of standardized toxin (ten times the fatal dose or " toxic unit ") and a given quantity of the serum under trial. The minimum quantity of the speci- men serum which will prevent a lethal result under these conditions is said to contain an ''antitoxic unit." If the serum does not come up to a certain strength of antitoxic power, the horse is subjected to the injection of toxin for a further period, and after a time the trial is repeated. When the antitoxic strength becomes satisfactory, the blood is drawn through a DISEASES OF THE SOLDIEE. 669 cannula passed into the jugular vein and is received into largfe flasks capa- ble of holding about 1.5 liters. When fiUed, these flasks are transferred to an ice-safe or cooling room, where they remain for about twenty-four to thirty-six hours, sheltered from light, until complete coagulation has taken place. The serum is then drawn off by pipettes. About 8 liters of horse's blood will, as a rule, yield about 3.5 liters of clear serum. After determining the antitoxic strength of the serum, a small amount of carbolic acid or tricresol is added as a preservative and the fluid placed in sterile bottles ; the label thereon stating the amount of serum, number of antitoxic units and date of production. The antitoxic strength of the serum appears to vary according to the animal from which it is produced. Sera for commercial purposes vary greatly in potency and their strength is often over-rated. In serum-therapy, as in other classes of medication, an absolute knowledge of the doses em- ployed is of the first importance. In general, for military use, the serum should be so standardized as to contain 100 antitoxic units per cubic cen- timeter. To produce more concentrated sera requires greater care, a longer period of inoculation and smaller and less frequent bleedings. For immunization of those exposed to the infection of diphtheria, an iu- jection of serum containing 400 to 500 antitoxic units is sufficient. Dysentery. Occurrence. — Of all the diseases to which troops are subject on active service, especially in hot climates, dysentery is one of the most formidable and important; and this almost equally on account of its frequency, its severity, the difficulty of its treatment and its proportionately high mor- tality. The disease is one which is peculiarly favored by camp life. History gives many instances in which dysentery has prevailed epi- demically among troops. It made frightful ravages in the army of Xerxes, in 480 B.C. ; and it is recorded that in the invasion of Italy by Theodebert in the year 538, one-third of his force died of this disease, compelling a retreat. The army of Henry IV. was reduced three-fourths of its effective strength before the battle of Agincourt through an epidemic of this disease. In 1773, half the English army at Hanau had dysentery, which decreased on the abandonment of the camp; and the same occurred in 1778 in the army of Prince William of Hesse. In 1787, the French army introduced an epidemic of this disease among the civil population of Mayence. In 1793 it ravaged the French army in Italy, and in 1812 in Poland. In Egypt, Napoleon lost more men from dysentery than from the plague which occurred at the same time. It prevailed largely during the Crimean War ; and Laveran states that in three months there were treated, in the hospitals at Constantinople, 9,919 cases of diarrhoeal disease — chiefly dysentery, of which 15 per cent, proved fatal. Before Metz, in 1870, it was one of the greatest causes of mortality in the besieged army. In the military opera- tions iu our own country, it prevailed in the French War of 1756, while during the Eevolution it became epidemic in the trenches before Boston. It was most extensive and fatal during the Seminole War in 1836 ; and the same was the case during the war with Mexico. During the CivH War period, July, 1861, bo June 30th, 1866, the average rate of admissions 670 THEOEY AND PEACTICE OE MILITAEY HYGIENE. for dysentery, per thousand strength, was 120.88; the death rate for the same cause and period was 3.67. While the admission rate varied but little during these years, the mortality steadily increased ; the death rate per thousand strength for this cause being 1.64 in 1861-62 and 6.31 in 1865- 66. Since the Civil War, the frequency of its occurrence in our service is shown by the following figures : Period. Admissions per 1,000 strength. Deaths per 1,000 strength. Period. 'Admissions per 1.000 strength. Deaths per 1,000 strength. 1868-84 1885-94 1895-96 39.04 6.52 13.05 0.59 .10 .68 1868-98 Year 1897 Year 1898 19.91 3.39 38.09 0.45 1.86 The rates for dysentery in foreign armies during time of peace, like those until recently obtaining in our own service, are low. Among the British troops stationed in the United Kingdom during the decade 1888-97, the admissions per thousand strength amounted to .5, the deaths to .2. For the year 1898 the admissions amoimted to .7 and the deaths to .03. The oc- currence of dysentery in the German army is shown by the following rates : Period. Admissions per 1,000 strength. 1881-83 to 1885-86 1.4 1886-87 to 1890-91 34 1891-93 to 1895-96 31 Period. Admissions per 1,000 strength. Year 1894-95 0.25 Year 1895-96 57 Year 1896-97 10 The milder cases are not taken into hospital in the German army and do not figure in the above rates. In the Austrian and Eussian armies the rates of admission, per thou- sand strength, have been as follows : Year. Austrian army. Russian army. Tear. Austrian army. Russian army. 1893 4.1 1.3 1.3 3.4 3.1 3 1895 1.2 .8 .6 23 1893 1896 1 6 1894. 1897 1 7 The case mortality in the Eussian and Austrian armies during the above period was twice as high as in our own military service or in those of England and Germany. No single point more clearly shows the value of modern military hygiene and sanitation than the great and progressive reduction of the rates for dys- entery which has occurred in all armies in the last two score years. Not only has the proportion of admissions been largely decreased but the case mortality has been reduced to an even greater degree. For our own army the improvement — as well as the favoring influence of field service on the occurrence of this disease — is well shown in the accompanying chart; for the French army in Algeria it is stated by Coustan that, in 1847-48, out of every 1,000 deaths from all causes, 403 were fi-om diarrhoea and dysen- tery, chiefly the latter, while for the period 1867-78 this disease occa- sioned but 72 deaths out of each 1,000 — and the rate has fallen progres- sively since that time. Cause. — The dysenteric condition, as far as present knowledge goes, appears to be due to several different exciting causes. First, a tropical form DISEASES OE THE SOLDIEE. 671 directly due to an amoeba ; second, various diphtheritic and catarrhal forms without amoebae, apparently produced by bacteria of different kinds, but =iillllllllillllll|l /i..;:,-iV-- /i l""-^-- „ V-J I \ 1 T '" r — f- , VL ;... I ;..::::::::ai" i — I::: sl' ,*:::::::::::::r '::::::::::::::r:: :::: ' tr * ik^.5 *" r ' ; i >U4JJ K'iK 'n /" """A ^''^ •, u '"'^-. ::...::::::... FIG. 329. -Admissions lor Dysentery in the United States Army, per Thousand Strength, lor the Period 1861-98, Excluding the Year 1887. the nature of which has not been fully investigated. This form is rarely fatal. Third, the Japanese form of dysentery as first investigated by Ogata. In many instances there appears to be an infection of dysentery engrafted on a previously existing diarrhoea, and this is nowhere more frequently ob- served than among troops during field service. On the other hand, it is probable that the specific cause of dysentery is often introduced into the system without giving rise to the disease ; it being only when the resistive powers of the mucous membrane are impaired by other causes that it be- comes vulnerable to attack. The amoebae coli, as seen in the stools of a case of dysentery, are roimded or somewhat irregular proto- plasmic masses, usually measuring .012 to .035 mm. in diameter, though larger forms are met with. The amoeba has an enveloping ectosarc of clear material and an endosarc of granular protoplasm. It possesses a homogeneous, refractive nucleus, and usually several vacuoles are to be seen in its protoplasmic body. Sometimes it contains red corpuscles — ^which appear to undergo digestive li- quefaction — and also bacteria. The amcEbse break down with some rapidity outside the body, and examination of dysenteric stools twenty-four hours after being passed usually fails to detect any of them. They were once thought to have been successfully cultivated in hay infusions, but it is now recog- nised that the results obtained were erroneous. In the stools they are most Fig. 330.— Amoebae oI Dysentery, a and b show amoebae as seen in fresh stools ; c shows an amoeba in Bxed Him preparation. (After Mulr and Ritchie.) 672 THEORY AND PRACTICE OF MILITARY HYGIENE. numerous in the small grayisli-yellow collections of pus. They are less frequent in the blood-staiaed mucus, and are rare ia the greenish masses of detritus. On a warm slide, these organisms show active movements. The amoebae frequently penetrate into the intestine ; being found in the mucous membrane when tilcers are being formed, and sometimes making their way into the submucous and muscular coats. In tropical abscess of the liver the amoebae are usually to be detected, and not infrequently are the only organisms present. It is unknown in what form the organism survives outside the body and leads to the propagation of the disease. If it pos- sesses the qualities common to other amoebae, it is quite probable that conditions are found in both water and soil, especially damp and marshy soils, which favor its existence and development. In investigating an epidemic of dysentery in which amoebae could not be found, Ogata observed in the discharges, but especially in sections of the affected tissue, enormous numbers of small bacilli, sometimes in practically pure cultures. These bacilli he regarded as the cause of the disease, and his work has been confirmed by Shiga, Flexner, Strong and others. The spe- cific bacilli vary in their morphology with the nutrient medium used. On agar cultures they appear as short rods, and not rarely in pairs ; in old bouOlon cultures the rods are very much longer. The organism presents no capsule, forms no spores and possesses no flagella. Staining is read- ily accomplished by ordinary methods, the bacillus being decolorized by Gram's method. It can be cultivated on the usual media at room temper- ature ; it does not liquefy gelatin nor does it coagulate milk. Litmus milk is slightly reddened after twenty-four hours. The bacillus is pathogenic for rats, mice and rabbits when injected subcutaneously ; but when injected into the rectum it does not produce dysentery in the lower animals. Predisposing Causes. — Dysentery occurs both endemically and epi- demically in all climates. For the decade 1888-97, the admissions for this disease, among British soldiers in India, China, Straits Settlements, Ceylon, West Indies, Egypt and Cyprus, and Mauritius, amounted to an average of 15.17 per thousand, while for the United Kingdom they were .5, and for Canada . 1 per thousand. In our own army, for the fourteen months. May, 1898, to June, 1899, inclusive, the deaths from diarrhoea and dysentery are given as 1.3 per thousand of troops serving in the United States; 5.69 for those serving in Cuba; 2.08 for those in Porto Eico and 2.48 for those sta- tioned in the Pacific Islands. For the last six months of 1897 the admis- sions for dysentery in the Spanish army in Cuba amounted to 72 per thousand strength; the death rate to 10 per thousand strength. In temperate cli- mates, summer is the season when this disease, like all diarrhoeal affections, prevails to the greatest extent; in the tropics it occurs most frequently at the close of the rainy season. Few facts in connection with the relation between dysentery and climate or season are more clear than those which indicate the influence of vicissitudes of temperature and exposure to chill- ing in determining attacks. The reduction of dysentery in the French army has been thought to be due, to some extent, to the provision of conve- niences which render unnecessary the chUling of the soldiers at night while attending to the calls of natm-e. Dysentery, though occasionally occurring in dry places, manifests a decided preference for damp and water-logged soils. Of great importance in its epidemic occurrence is the saturation of the DISEASES OF THE SOLDIEE. 673 site of the camp or post with urganic and particularly faecal material. The terrible epidemics of former times undoubtedly resulted chiefly from long occupancy of camp sites, resulting ui fouling of both the soil and water. All cachectic states of the constitution powerfully predispose to dysentery. Scurvy and malaria are no exceptions to this rule, and the latter gives rise to a form of the disease peculiarly resistant to treatment. Patigue, expo- sure, hardship and anxiety also appear to have no small influence in deter- mining its occurrence. A faulty dietary, especially as found in insufficient, coarse or improperly cooked food, green or over-ripe fruits, an excess ofsalt meats, or the over-use of alcoholics, notoriously favors dysentery. These points were particularly well illustrated by the happy change in the condition oi the British army in the Crimea, in respect to the prevalence of dysentery, as soon as its wants as to diet, shelter and clothing were properly satisfied. A large number of outbreaks of dysentery have occurred during the prevalence of typhoid fever, the development of both apparently being fa- vored by the same general conditions. Several striking illustrations of this fact have lately been recorded among our troops in the Philippines. Dysentery is particularly liable to affect young soldiers, through then- disregard of matters of hygiene and probably greater individual susceptibil- ity. Tripler states that dm'ing the war with Mexico the death rate from dysentery was twice as high in the newly raised troops as in the old army. Negro troops appear especially liable to contract dysentery. In our own service, for the decade 1879-88, the relative rates per thousand strength were as follows : Admissions. Deaths. ' White troops 13.65 0.30 Colored troops 39.65 .32 In the British forces stationed in the West Indies, for the decade 1888-97, the rates for dysentery among European troops, per thousand strength, were 6.9 for admissions and .33 for deaths. For the same period, the rates for the native negro troops were respectively 16.8 and .44. Coustan, on the other hand, notes an immunity to this disease among the natives of northern Africa, citing an instance where "a French column in Algeria suffered severely, while the native Arab followers, who set every law of hygiene at defiance, escaped sickness." From the greater care which they are able to give themselves, and to their greater attention to sanitary detail, officers are much less liable to contract dysentery than are enlisted men. Method of Infection. — The commonest recognized portal of infection is the mouth, the specific exciting cause of the disease gaining entrance in contaminated water or on uncooked foods. Experiments show that infec- tion can occur through the rectum, but this is probably a rare mode in human beings. The instances in whicli outbreaks of dysentery have been traced to the use of impure water, particularly that contaminated with fsecal matter, are very numerous ; and of all causes contributing to the occurrence of this disease, that of impure water is the most important. In most in- stances, this fluid merely serves as a vehicle for the introduction of the spe- cific cause into the system, but it may at times have a predisposing influ- ence through its mitative action on the bowel. Prieur has reported an epidemic of three hundred and fifteen cases of dysentery occurring in 1891 m a small garrison in the French army, which 43 674 THEOEY AND PEACTICE OF MILITARY HYGIENE. he regards as directly traceable to the use of the common latrine by the first patient, who, as the affection became more advanced, was unable to keep from voiding his discharges on the floor and seats. ISTo other case appeared until six days after the first case was well developed. He believes that the subsequent infections were directly due to the dysenteric discharges being mixed with the dirt on the floor of the latrine and then being carried into barracks on the shoes of the soldiers. The food of the latter was then con- taminated with this infectious material ; a result rendered very possible by the.absence of mess-rooms in French barracks and the fact that the soldiers usually sit on stairways or on the floors of halls or barrack -rooms while eating their food. Prophylaxis. — This is dependent on the etiology. All drinking- water should be protected from contamination, and when open to the sHght- est suspicion should be sterilized by heat. It is well to keep in mind that if pure water be not provided in a hot climate, the men will get it from any source, however impure. Food should be carefully watched in respect to its sufficiency, quality and the thoroughness of its cooking. When an outbreak of the disease threatens, all raw fruits and vegetables should be excluded from the diet ; and, if possible, hard bread and beans, which are difficult of digestion and hence irritating to the intestiaal canal. Chilling, especially of the abdomen, should be avoided, and the use of the flannel band may become advisable. The camp site should be dry and well dramed. If the disease appears with any severity, the camp should be promptly moved without waiting for further developments. Instances have been known where regiments were affected with dysentery every time they encamped on a certain space, and old camping grounds notoriously favor the occurrence of this disease. The camp should be carefully policed to limit the fly plague, and the contents of trench latrines disiafected and covered twice daily. If possible, the excreta should be burned. Any part of the latrines liable to be soiled with ejections should be disiafected twice daily with suitable solutions. Great care should be taken to prevent con- tamination of the water supply with feecal matter, either from the location of the latrines or from uncleanly habits on the part of troops. Dysenteric patients should preferably be removed from the locality in which the dis- ease was contracted : this being an important factor in securing recovery in many cases. Inasmuch as dysentery occasionally spreads in hospitals where large numbers of such cases are under treatment, the necessity of free ven- tilation, abundant air space and the prompt disinfection of the stools, bed- pans, commodes and enema-tubes are matters of the first importance. It is essential that during an outbreak of dysentery all men affected with diar- rhoeal symptoms should at once report for treatment for the same. Enteeic or Typhoid Fevek. Occurrence. — The history of enteric or typhoid fever, as a disease of soldiers, extends over a period of scarcely fifty years; it having been previ- ously confused with several other affections. About half a century ago, the disease was differentiated from typhus fever by Murchison ; both pre- viously being classed together by medical officers as "spotted fever," and undoubtedly much of the fatality which, prior to this time, had been re- DISEASES OF THE SOLDIEE. 675 garded as due to typhus was in reality due to typhoid infection. For a long time, no distinction was made between enteric fever and the continued malarial fevers. Shortly before and during the Civil "War, however, medi- cal officers were forced to recognise the difi'erent characteristics of typical cases of these diseases, and about the same time the term " typho-malarial " was adopted to cover that class of cases which, while they presented some of the clinical symptoms of both diseases, were apparently identical with neither. Later, the fact that most of these cases of "typho-malarial " fever were in reality typhoid infections was strongly suspected; but it was not until Laveran, of the French army, discovered the malarial parasite that the differentiation between enteric and malarial fevers was definitely made. In the French army, the official recognition of the existence of a disease intermediate between malaria and typhoid was withdrawn in 1888, and about the same time the term " typho-malarial " was discontinued in our own medical nomenclature. This example has since been followed in all the more important armies, and military statistics for this disease, for the past ten years, may be regarded as much more accurate. In the Eussian army, however, even as late as 1897, no small proportion of the continued fevers were classed as "undetermined " in nature. It is obvious, therefore, from tlie difficulty which has until recently existed in the recognition of typhoid fever, that statistics for the periods prior to the past decade are of little value for purposes of comparison between different armies — and even for the same service they are not free from error. For our own army, it may safely be assumed, from a better knowledge of the nature of the typhoid infection, that cases which have been recorded as "typho-malarial " were in reality chiefly cases of enteric fever. In a few instances, however, the typhoid and malarial infections appear to be present at the same time. Typhoid fever, at the present time, is by far the most important disease affecting soldiers. While it prevails to some extent among troops in gar- rison, it is among soldiers in the field, and especially those in camps of more or less permanency, that it makes its greatest ravages. This fact depends merely upon the greater difficulty of properly disposing of the excretions of the human body under the latter circumstances. In this country, as in aU temperate or tropical regions, enteric fever is so prevalent and its specific cause so widely disseminated that no encampment of any siae or permanency can be expected to remain free from its infection. Thus in the camps of our army, during the war with Spain, not a single regiment of those composing six army corps escaped infection. According to the board appointed to investigate the epidemics of typhoid fever during this war, more than twenty thousand cases of this disease occurred among our troops encamped within the limits of the United States during the summer of 1898 ; nearly aU the regular troops and ninety per cent, of the volunteer regiments developed typhoid fever within eight weeks after going into camp — some as early as three weeks— and in the northern quite as much as in the southern parts of the country. This condition, far from being unusu- al, is what has commonly prevailed in the past among troops of all nations on active service; and Davies gives a number of instances of early epi- demics occurring in successive British military expeditions. The recent Anglo-Boer War in South Africa was no exception to this rule. It has been repeatedly observed, especially in the camps of 1898, that whOe 676 THEQRY AND PEACTICE OF MILITARY HYGIENE. troops in camp are heavily scourged, the surrounding civil population may remain whoUy unaffected. The conclusion is inevitable that the conditions ordinarily found in military encampments, or governing troops in the field, are extremely favorable to the propagation of this disease; this fact being abundantly demonstrated by figures_ for our own service. During the Civil War period, 1861-66, the admissions for typhoid and " typho-malarial " fevers amounted to 57.71 per thousand strength, while for the sixteen years following the war, 1868-84, the admissions for the same cause were only 6.29 per thousand strength. Again, in 1898, during the war with Spain, the admissions for typhoid fever were reported as amounting to 88.55 ])er thousand strength , while the board wliich investigated the epidemics of the disease which occurred during that year, and which critically reviewed the official records, states its belief that these official figures should be raised to 192.65. During the year 1897 the admissions amounted to 6.25, and during the decade 1885-94 they were only 5.51 per thousand strength. '"::!::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: Ll\ " 'r ' " "^ ^ " f " " - ">..'"■' ""' " Fig. 331.— Admissions for Typhoid and " Typho-Malarial " Fevers, per Thousand Strength, occurring in the United States Army during the Period 1861-98, excluding the Year 1867. Throughout the period of peace 1868-97, the rates for typhoid fever showed no very great variation except for the years 1882 and 1883, when sharp localized outbreaks of the disease occurred, and for the years 1874 and 1875, when the rates fell much below the normal. Of late years the disease has shown a tendency to become more prevalent, in spite of the much improved sanitary conditions under which the soldier now lives. It is possible that the comparatively recent reduction in the period of enlist- ment, from five to three years, through the greater proportion of more susceptible material in the army which is thus brought about, has had an effect in neutralizing sanitary improvements as far as their influence on enteric fever has been concerned. The relative prevalence of typhoid fever in our service since the year 1860, together with the remarkable increase induced by camp life, is shown by the above diagram. During time of peace, the mortality from typhoid is not high in our army as compared with that for the country at large. For the year 1896 the death rate was .48 per thousand; this being lower than the typhoid DISEASES OF THE SOLDIEE. 677 mortality rates in most of our large cities, as Washiagton, Chicago, Pitts- burg and Philadelphia, notwithstanding the greater susceptibility of men of the military age to this disease. In the French army, however, Coustan states that the relative amount of sickness due to typhoid fever is five or six times greater than among the civilian population. Brouardel showed that for 183 French towns, for the period 1886-90, the death rate from typhoid fever for all ages of the civil class was .56 per thousand; in young men 20 to 25 years of age the proportion of deaths was .72 per thousand, where Viry estimated the true army mortality at 2.6 and Marvaud at 2.1 per thousand. During time of peace there has been no great epidemic of this disease in our army ; the highest rates of admission being given in the years 1882 and 1883, when the admissions per thousand, for the entire army, amounted to 11.23 and 15.06 respectively. The rates are undoubt- edly kept low through the fact that our troops have in the past been scat- tered in small commands over a large area, and that the infection of an individual water-supply was therefore not able to affect a large number of troops at once, as is often the case in foreign armies. A considerable pro- portion of those exposed to the typhoid infection have at times contracted the disease. Viry and Coustan cite epidemics in the French army, in 1875, in which 10 per cent, of those exposed contracted the disease at Nanly, 18 per cent, at Saratory and 25 per cent, at Brest. In 1889, of the troops at Dinau, 60 per cent, contracted typhoid during a single epi-' demic. The board which investigated this disease during the war with Spain concluded that not less than one-fifth of all the troops located at the camps of mobilization had suffered from typhoid fever, either in recognized or unrecognized forms. It also stated that in all probability the deaths due to typhoid fever amounted to more than eighty per cent, of the mortality from all diseases during that period. With regard to the occurrence of typhoid fever in foreign armies, Cous- tan gives the rates in the French army as follows : Admissions per 1,000 strength. Deaths per 1,000 strength. Admissions per 1,000 strength. Deaths per 1,000 strength. Before 1888 From 13-31 13.3 11.6 10.5 3.5 1.7 1.6 1.71 1891 10.77 13.13 9.59 1.95 1888 1893 1893 .. 1.54 1889 18 f ^ J 1 : I 1 - 3 1 2 1 i 1 1 1 1 1 1 1 ,„ _ _! _ _ L II i jj 1 1. 1 L 1 1 J 1 J i 1 ^ rio. 335.— Typical Water-Bome Epidemic of Typhoid Fever, Occurring Among the Troops at Wittenberg^ Germany. (After Gaflky.) water-supply occurs. In typhoid spread by other means than water, as in camp epidemics, the onset of the epidemic is gradual. With each case, additional sources of infection are developed and the prevalence of the dis- ease steadly increases as long as efficient preventive measures are not taken and there is an abundance of susceptible material. Besides the danger of using an infected water for drinking purposes, it is important to recognize the fact that its use in washing the hands, face- and other parts of the body may give rise to the disease. Many well- demonstrated instances might be quoted to illustrate this point. Among articles of food, milk is not infrequently contaminated with typhoid germs from infected water which may have been added or used to wash the dairy utensils. Venders of "soft drinks," so numerous in the- vicinity of a military encampment, are usually not at all particular in respect to the quality of the water used in compounding their preparations. During the war with Spain, much of it was probably infected. In the same way, Kttle care is taken to prevent specific contamination, through dust and flies, of the articles of food which such venders expose for sale. DISEASES OE THE SOLDIEE. 683 Many articles of food which are eaten uncooked are liable to spread the disease, especially vegetables. Eecently an epidemic of typhoid fever occurred in the insane asylum at Northampton, Mass., resulting from the use of celery watered with filtered sewage. Among many similar cases, one was lately reported by Ferre in which an outbreak in a school followed the use of vegetables watered with the contents of a cesspool which received the evacuations of the pupils. Water-cresses grown in ditches contaminated by sewage have been known to serve as the vehicle for the infectious agent. In 1895, Deshon reported several cases of typhoid at a western station which he believed could be traced to the use of heavy, sour and indigesti- ble bread. Among troops in camp during warm weather, the use of food contaminated with typhoid bacilli, brought from the latrines by means of flies, is a factor of the greatest importance in spreading the disease. Numer- ous observers have demonstrated the presence of tlie specific bacillus in the excrement of flies made to feed on infected material, and colonies of typhoid bacilli have been shown to develop in the tracks of flies which had been allowed to settle on typhoid discharges and then made to walk over a suit- able solid culture medium. Vaughan states that during 1898, in some of the large military camps where lime had recently been sprinkled over the contents of the latrines, flies with their feet whitened with lime were seen walking over the food. He also noted that officers whose mess-tents were protected by means of screens suffered proportionally less from typhoid fever than did those whose tents were not so protected. Where flies are numer- ous in camp and are constantly settling upon and contaminating articles in common use, it is easy to see that, even if the food and drink be protected from their invasion, an infection may readily be brought about by touch- ing the lips with soUed fingers which have come in contact with articles upon which the typhoid bacilli have been deposited. The typhoid epidemics of 1898 gradually decreased with the approach of cold weather and the disabling of the fly as a carrier of the infection. Where a strong wind constantly blows from the same direction, a fly-borne infection wiU extend chiefly down wind ; as this insect always rises, and generally moves, in the direction of air-currents. These insects lay their eggs and hatch out in nearly aU organic material, especially if this be in a putrid condition. Howard regards horse manure as the most favorable breeding material, but in the camps of 1898 the larvae were often seen by myriads in the poorly policed latrines. Sprinkling the contents of the latrines with earth, as ordinarily practiced, did not appear to destroy them. Care with respect to preventing organic contamination of the camp space and in carrying out proper measures of latrine disinfection will do much to prevent then* development. The life of the fly is short, but the cycle of its development is rapid. According to Howard, under favorable con- ditions the egg hatches in eight hours, the larva passes to the pupal state in sixty hours to three days, while from pupation to the issuing of the adult requires about five days. As the life cycle is complete in about ten days and the individual insect lays about one hundred and twenty eggs, the enormous numbers in which flies frequently occur in camps are readily ac- counted for — since twelve to fifteen generations of the pest may be developed in the course of a single summer in temperate climates. Typhoid fever may also be transmitted by aerial infection from drains. 684 THEORY AND PRACTICE OE MILITARY HYGIENE. water-closets, latrines, dust-heaps, urine or faecal discharges which have been allowed to dry on the linen or person or in receptacles. In this con- dition, the bacilli are capable of being carried considerable distances through the air to settle down on water, clothing or food. It is not yet determined whether the disease can be contracted by breathing air containing suspended bacilli, but certainly in the case of mouth-breathers the latter should readily find their way to the pharynx and thence be washed into the alimentary canal by the act of deglutition. It is true that complete desiccation soon destroys the typhoid germ ; but it is not always completely desiccated, and Fliigge and Fischer have shown that this bacillus can successfully resist a considerable amount of drying. AUchin, moreover, states that but a comparatively slight current of air, four meters per second, is sufficient to raise germs into the atmosphere from the surface of wet ground. The dissemination of typhoid by means of infected dust was undoubtedly a potent factor in its spread, in 1898, in the camps at Jacksonville and Tampa. In this connection it is interesting to note that, in 1885, the British troops at certain stations in the Soudan used only distilled water, yet typhoid was very prevalent. No reason for the spread of the infection could be shown except that the excreta were dried, converted into dust and scattered over the camp by the desert winds. In the French army, NoUet was recently able to demonstrate the presence of the typhoid bacillus in the dust of cracks in the barracks at Cherbourg, at which station typhoid had prevailed epidemically. A typhoid infection may long exist in barracks. Thus after the Franco-German War it was found that typhoid fever continued to prevail for some years in German garrisons in which German soldiers or French prisoners, affected with typhoid fever, had lived. Direct qontact with typhoid discharges does much to spread the in- fection, especially among raw troops. Where lack of discipline permits the pollution of the ground in the vicinity of camps by the indiscriminate deposition of human excreta, a certain proportion of such discharges will assuredly be infected and thus infectious material may be carried into camp and tents on the shoes of incautious passers. Where the men throw then- blankets on the ground of the tent area for sleeping purposes, it is obvious that the inhalation of infected dust is more liable to occur. Uncleanly seats in latrines, or the ground therein, may specifically contaminate the persons and clothing of those resorting to them. Where line troops are detailed to do the heavier labor about hospitals, the opportunity for infection to be can-ied back into camp through their agency is often great. The board wliich investigated the occurrence of typhoid fever in 1898, was struck with the fact that men who were closely associated in the same company or tent almost simultaneously developed typhoid fever in many instances — appar- ently through a localized infection derived from the same source. Heavy rains do much to disseminate typhoid among encamped troops, especially where there is bad sanitary police. Usually the increase in the number of cases after such rains is noticed in about ten days or two weeks. Where sinks are dug in impervious soil and are so located as to receive sur- face drainage, they may be overflowed by storm waters and distribute their contents over the adjoining surface — these to be later dried and scattered as dust by the feet of men and animals and the wheels of passing wagons. DISEASES OF THE SOLDIER. 685 During the war with Spaia, in camps where the tub system for the reception of excreta was ia use, careless handling and transportation by the scavengers resulted in the scattering of f cecal matter, much of which was infected, broadcast over the camp area. It may be accepted that wherever a large body of men assemble and their own excretions are permitted to accumu- late and contaminate their surroundings, an outbreak and spread of typhoid fever may be expected to occur. A fruitful cause of the dissemination of typhoid throughout a camp lies in the fact that no small proportion of soldiers, with mild infections or with ambulant cases of typhoid, either do not go on sick report until the typhoid condition is well advanced, or not at all. In many instances, also, the nature of the comparatively slight prodromal symptoms presented are not recognized by the medical officer, and the case for a considerable period is treated in quarters as one of diarrhcea or similar trifling affection. This is particularly true in those instances, noted by Allchin and others as being not infrequent where the individual has been exposed to great hard-i ships, in which the temperature is normal or subnormal throughout the attack. As already stated, the stools in typhoid fever are probably infec- tive even during the period of incubation ; and there undoubtedly is a con- siderable proportion of cases in which an infection does not develop the typical disease, either through an attenuation in virulence of the specific germ or insusceptibility on the part of the subject. In some instances the typhoid bacillus may grow in the intestinal tract of an individual and pass from the same without causing typhoid fever in the soldier serving as host ; this probably occurring chiefly when many irritative saprophytic germs are taken in with a relatively small number of typhoid bacilli. The experi- ence of Prench medical officers in Algiers and Tunis would seem to show that apparently healthy persons may carry the germs of 'typhoid, which, later scattered under favorable circumstances, originate the disease. British medical officers have noted the same in India and elsewhere. Many instances have been recorded, also, in our own service, especially in the days of Indian warfare, where outbreaks of the disease occurred among troops who had been for considerable periods in regions which were not known to have ever before been penetrated by man. For the British service, an instance of this is furnished by the Afghanistan campaign, in 1878-80; for the French army, in the Gran expedition of 1885, it is stated that commands encamped at desert stations never before occupied, and that typhoid fever not only appeared but assumed epi- demic proportions. From such instances, medical officers in all military services have favored a theory of the de novo origination of typhoid, or of the metamorphosis of the specific germ from the colon bacillus under suitable conditions. It is easy to understand, however, in the light of recent investigations as to the infectiveness of urine after typhoid fever, and from the fact that typhoid bacilli may retain their virulence for several months when present on infected fabrics carried in the blanket roll, how the microbe of this disease can be transported by troops for long periods, without its presence being suspected, and then give rise to an epidemic when favorable conditions for its development are encountered. Since the period of incubation is ten or twelve days — or even in some cases as long as twenty-three days — it is obvious that infected individuals may be passed as 686 THEORY AND PKACTICE OF MILITAEY HYGIENE. healthy and sent to other stations, there to develop the characteristic symp- toms of the disease and to serve as the starting-point for new epidemics. This was repeatedly shown to have occurred among recruits sent out from Jefferson Barracks — formerly endemically affected with typhoid fever — to western stations. Further, convalescents from typhoid, returned to duty at too early a date, may be unrecognized but potent agents in the origiiiation of the disease in others. AU these classes of cases are particularly a men- ace to the health of a command under canvas, since by their agency every latrine in the camp may become infected and the probability of contami- nation of the camp space, and perhaps the tentage, by infected urine and saliva, is so great as to approach certainty. Direct contagion from the obviously diseased to the healthy plays a strong part in the spread of enteric fever. There is no reason for belief that the poison is given off in the breath or the emanations from the body, but it is probably contained only in the urine, faeces and, to somfe extent, the saliva. If these be properly disinfected and disposed of, strict cleanliness be observed and attention be paid to the disinfection of the soiled linen, the risk of contagion may be reduced to a minimum. Nev- ertheless it has not been found possible, with all precautions, entirely to prevent the spread of the disease to the attendants. During the typhoid epidemic of 1898, the admissions for this disease from the Medical De- partment and Hospital Corps were officially reported as amounting to 193.41 per thousand strength, whereas the rate for the army as a whole was 88.56. This fact specifically demonstrated the immediately transmissible character of the affection, and probably was chiefly -dependent upon inadvertent in- fection of the hands or clothing of the attendants. It is important that nurses in charge of typhoid cases should not have the care of patients suf- fering from other diseases. Predisposing Causes to Typhoid Among Troops. — Typhoid fever is found in all climates outside the polar regions, but increases in preva- lence as the equator is approached. In the British army, distributed as it is all over the world, the prevalence of typhoid varies greatly. For the year 1898 and the decade 1888-97, the rates per thousand of British troops, at different stations, were as follows : Tear 1898. DECADE 1888-97. station. Admissions. Deaths. Constantly siclj. Admissions. Deaths. Constantly sick. United Kingdom Gibraltar 1.9 4.3 21.3 81 0.22 1.32 6.38 23.40 0.81 .74 2.44 11.13 1.2 5.4 6.6 31.3 1.3 34.8 9 12.8 15 6.9 1.5 1.9 31.8 0.24 .95 2.48 4.37 .21 6.38 2.15 1.87 5.34 2.13 .50 .88 5.75 0.20 1 05 Malta Egypt and Cyprus Canada 1.15 3.90 .25 15 1.1 32.9 14.6 3.1 1.9 .7 36.3 3.31 .55 5.77 4.86 1.43 .64 .71 10.04 3.36 .23 4.88 2.37 .09 .39 .17 4.90 5 13 West Indies 1 36 South Africa 1 93 Mauritius Ceylon . . 2.15 84 China 31 Straits Settlements India .29 3 13 DISEASES OF THE SOLDIER. 687 On averaging together the figures for the two cold stations, the United Kingdom and Canada, for the decade 1888-97, the admissions per thou- sand strength are seen to be 1.25, the deaths .22 and the constantly sick .22. For the same period, the average rates for the remaining stations, located in hot climates or in the tropics, were: Admissions, 12.4; deaths, 2.97; constantly sick, 1.92. From these figures it appears that British soldiers in hot climates or ia the tropic's are almost exactly ten times as liable to contract the disease as those serving in cool climates ; while the liability to death from this disease is fourteen times greater under the former conditions. The apparently shorter course run by typhoid in the tropics, as expressed by the rates for constant sickness, is merely due to the higher rate of mortality, by which the elevation of such figures, through tardy convalescence, is prevented. Coustan states that typhoid fever is far more prevalent in Algiers and Tunis than in France. In our own ser- Enteric fever. Typho-malarial fever. Fig. 336.— Chart Showing the Distribution by Months, per Thousand Strength, of Cases Diagnosed as Enteric Fever and Typho-Malarial Fever, Occurring In the United States Army During the Decade 1875-84. vice, for the year 1898, the admissions per thousand of troops stationed in the tropical islands were 102.18 and the deaths 13.88; while of troops within the United States duriag the same period the admission rate was 85.46 and the death rate was 8.79. It should be remembered, however, that troops were exposed to tropical influences but a small part of that year, and that for full periods of service the difference in rates would un- doubtedly have been much greater. Thus for the year 1899, under more settled conditions, the admissions to hospital per thousand strength amounted to 27.09 for all the tropical islands and to 10.85 for troops serving in the United States. Within the limits of the United States the influence of locaKty is marked ; the amount of typhoid fever in the De- partment of Texas being almost twice as high as in any other military de- partment. In 1890 it was more than six times as high as in the Depart- ments of the East, California and Arizona. In 1897 it was fourteen times as high as California and much higher than in the other departments. 688 THEORY AND PRACTICE OF MILITARY HYGIENE. As to season, the disease prevails in our army especially during the late summer and early autumn. For the decade 1875-84, as shown by the diagram on the preceding page, the disease occurred least frequently during March and April, and prevailed most extensively in August and Septem- ber. In the French and German armies it prevails to the greatest extent during and after the manoeuvers in August and September; in the Aus- trian army its prevalence is greater during the July manoeuvers. Certain notable outbreaks have occurred in the spring, but these are invariably to be traced to a water-borne infection and are exceptions to the general rule. Military experience shows that an infection of enteric fever often fixes persistently upon a single barracks, post or district. As a rule, in those localities where the disease is endemic it will be found that unsanitary conditions abound; notably, impure water-supply, defective methods and arrangements for the disposal of excreta, and want of care in respect to preventive measures. In India, typhoid fever has been found to be a more difficult disease to eradicate from military posts than cholera ; persisting with great tenacity and recurring year after year in spite of all efforts. It has even been found necessary to abandon stations for this reason. Within these endemically infected areas, new arrivals are especially liable to attack, those long resident appearing to acquire a relative immunity through repeated mild infections. Great importance was attached by Pettenkofer to the height of the gromid-water in endemically infected regions ; a low ground water, in his opinion, always coinciding with outbreaks of the disease. This re- lation between typhoid fever and ground-water apparently holds true for certain localities only and need receive no serious consideration. Negroes and other colored races undoubtedly possess an inmnmity to typhoid fever. By some this is regarded as a racial characteristic, by others as an acquired immunity resulting from an attack of the disease during childhood. In India, the blood of the natives, as a class, has been recently shown to give a positive reaction with Widal's test in most instances. In our own service, the disease is undeniably less frequent among the negro troops than among the whites. For the period 1867-83, the admis- sions per thousand white soldiers, for typhoid, not coimting typho-mala- rial fevers as then recognized, amounted to 3.58, while the admissions for colored troops were 2.59 per thousand strength. For the year 1887, the admission rate for white soldiers amounted to 4.25, for colored soldiers .93. During the decade 1887-96 the admission rate among the whites was 5.93 and for the negroes 2.43. It is interesting to note that for our few Indian soldiers, during this latter period, the admission rate for typhoid was only .47. During the year of war, 1898, the relative insus- ceptibility of negro troops as regards typhoid fever was especially notice- able; the admission rate being 93.24 per thousand white and 27.64 per thousand colored troops — this, too, in spite of the fact that the negro regiments saw harder service. On the other hand, when the disease has actually occurred, the case mortality has been much higher among the colored soldiers than the whites. Typhoid fever occurs only exceptionally among the native troops in India, and their immunity as compared with white soldiers serving in that country has long been noted. As illustrat- ing how great this difference in susceptibility really is, it may be stated that, in 1893, of the forces in India, typhoid fever was responsible for DISEASES OF THE SOLDIEK. 689 1.41 per cent, of the sickness and 42 per cent, of the mortality among the English soldiers, and for only .03 per cent, of the sickness and .4 per cent, of the mortality among the native forces. Such an immunity would seem to have an important hearing on the question of raisiug native forces for controlling our own tropical possessions. For the white race, nativity ap- pears to be a factor of some slight importance. In the United States army, during the seven years 1890-96, the admission rate for typhoid fever from the native-bom Americans, per thousand strength, was 5.69 ; for the soldiers of German nativity, 5.41, and for those born in Ireland, 5.02. Tj'phoid fever is especially a disease of young soldiers. How much greater their susceptibility is, can best be appreciated by reference to the accompanying diagram, in which the number of admissions are seen to decrease progressively by almost exactly one-half during each five-year period up to the age of 35. Not only are young men more liable to con- ^r- 2^ar,lujti*r. to t. M. ZS t, i3. 30 •■ 34. iSaS9. •fiJa-**. ifre.'^f. '''*r- ^H ^H ■'^ ^^B '-^ H 1 -1— ^^H _^ -*— ■ ■ ^^g -^^_..-. IolI , ■— — ■— — ■ — cz^B:^ p= — Fig. 337.— Admissions for Typhoid Fever, In the United States Army, per Thousand of Each Glass, Arranged According to Age, Occmring during the Seven Tears 1890-96. , tract this disease, but the mortality also, among those affected, is higher. For the period 1890-96, in our army, the deaths per thousand of each class were as follows : Age. Death rate. 19 years and under 3.33 20 to 24 inclusive 95 25 to 39 " 69 30 to 34 " 23 The case mortality for this period was 16.02 per cent, for soldiers 19 years of age or under, 9.21 per cent, for those 20-24 years of age and 8.89 for those 30-34 years of age. Length of service, in which factor age must clearly be considered to enter, also markedly influences the occurrence of typhoid. The report of the surgeon-general for 1885 shows the relative prevalence of this disease, excluding small fractions, among men of different periods of service, to be as follows: Percentage of total deaths from typhoid furnished Length of service. by each class. 6 months and under 48 Over 6 months and under 12 16 Over 1 year and under 2 14 Over 2 years and under 3 5.5 Over 3 years and under 4 4.5 Over 5 years 7 Length of service not stated 4.5 44 690 THEOKY AND PEACTICE OF MILITARY HYGIENE. In respect to English-born soldiers in India, Eyre and Spottiswoode state : " The susceptibility of young soldiers to this fever is clearly shown in the length of residence in India ; for while the death rate from typhoid was 4.98 per 1,000 in the first and second years' service, among those in their third to sixth years and seventh to tenth years it was 1.55 and .55 respectively." The report of the Sanitary Commissioner of India, for 1896, states that out of the total number of deaths at all ages from enteric fever, 78 per cent, were between 20 and 24 years of age and 36 per cent, were in the first year of residence. In "India, the prevalence of the disease among troops appears to depend chiefly upon the amount of susceptible material presented. This amount of susceptible material is of course variable; but, so far as the United States army is concerned) the board which investigated the typhoid outbreaks during the war with Spain believed that the amount of susceptible individuals in a regiment might be regarded as one-fourth to one-third the total strength. The influence of the branch of service upon the prevalence of typhoid fever is by no means small. For the period 1867-83, inclusive, the ad- mission rates, per thousand strength, were as follows: Cavalry, 19; in- fantry, 4.6; artillery, 2.5. For this sixteen-year period, the cavalry thus suffered more than seven times as much from typhoid as did the artillery and nearly five times as much as the infantry, while its death rate was more than three times greater than either of the others. This great dif- ference was largely due to the active field service against Indians required of moimted troops. For the seven-year period 1890-96, the admission rates, per thousand strength, were 8.03 for the cavalry, 5.74 for the ia- fantry and 4.74 for the artillery. In time of peace, the Medical Depart- ment is affected less than any of the above arms of the service ; during the war with Spain it. suffered more than twice as much as any of them. Overcrowding among troops certainly predisposes to epidemic typhoid fever; Marvaud gives figures to show that in the French army the mortal- ity from this disease bears a well-defined relationship to the number of men aggregated at a post. In camp, the effects of overcrowding are par- ticularly noticeable. This is perhaps due in part to a lowered vital resis- tance in the individual, but. is probably chiefly dependent, on the greater intensity of the infection resulting from the rapid propagation of the typhoid bacillus on a soil more highly contaminated with organic ma- terial, with a possible acquirement of more vii-ulent qualities under such conditions. Uncleanliness of person and surroundings is a powerful factor in the development of the disease among soldiers. Particularly is this the case with regard to the care and disposition of the excreta — the most important and difficult problem presented to the military sanitarian in the field. The common method of disposal of excreta and refuse in camp — by trenches and pits — offers many facilities for the development and spread of the specific micro-organisms. All coUecrtions of filth are liable to contamination and hence to become foci of infection. In garrison, the accumulation of organic matter under floors, dampened by the seepage of moisture through the use of excessive amounts of water in cleansing, affords excellent facilities for the development of the microbe. The influence of gi-eat fatigue, as a factor in the occurrence of typhoid. DISEASES OF THE SOLDIEE. 691 has been particularly noted by medical ojEficers in foreign services. The arduous and exhausting manoeuvers which take place yearly in all the larger European armies are invariably followed by outbreaks of this afifec- tion. It is well known that by over-exertion the bactericidal power of the blood is diminished and susceptibility to disease greatly increased. Cou- stan mentions, in connection with this subject, the experiments of Charrin and Eoger, in which rats made to turn a wheel until exhausted succumbed readily to inoculation by an attenuated culture of anthrax, whUe similar animals, not so exhausted, resisted the same inoculation. The loss of life from typhoid fever in infected regiments sent from Chickamauga to Porto Eico, in 1898, was materially greater than among similarly infected regi- ments which remained behind — probably through the greater hardship and physical strain to which the former were exposed. It is undoubtedly true that, while leaving the system more readily open to invasion by the ty- phoid germ, excessive fatigue induces more speedy development of the dis- ease in persons already infected. Insufficient or improper food, through the malnutrition or digestive disturbance which results from its use, may facilitate the invasion of the organism by the typhoid bacillus. Prophylaxis.- — In the prevention of epidemics of enteric fever among troops in garrison, a pure water-supply is of the first importance. With troops in camp, while the water should be of good quality, an early and correct diagnosis of the cases of this disease which first appear is essential in pre- venting its spread. If the water-supply be regarded as liable to pollution, it should, in garrison, be filtered through the Berkefeld apparatus before being used for drinking purposes. In the field, and sometimes in garrison, water is best sterilised by boiling — preferably by the Forbes apparatus. If the water is originally pure, as water from springs, deep or artesian wells or unpolluted surface-waters, it will only be necessary to ensure against its contamination before use. Where such water is dipped from open barrels with possibly unclean cups and hands, it wOl be evident that during the prevalence of typhoid fever the contamination of drinking- water in this way may not be rare. The receptacles for drinking-water should therefore be tightly closed and the water drawn off by means of faucets. Since, in camps, enteric fever is more directly propagated from the sick, and since the latter can through their discharges soon dissemi- nate the disease through large bodies of troops, the prompt recognition and isolation of typhoid cases, with the immediate disinfection of their excreta, equipments, tentage and surroundings, is of the greatest import- ance. As already intimated, the diagnosis of this disease is frequently a matter of much difficulty and may be impossible in all instances, but con- stant watchfulness on the part of medical officers wHl reduce this error to the minimum. The board investigating the typhoid epidemics pre- vailing during the war with Spain concluded that less than half of the cases of this disease which occurred among troops were correctly diagnosed ; but stated its opinion that, in recognising this proportion, the army medi- cal officer probably did better than the average physician throughout the country does in his private practice. Any such error of diagnosis, how- ever, implies too great reliance upon the mere clinical symptoms of enteric fever — which, it has been stated, are frequently modified or largely lacking 692 THEOEY AND PEACTICE OF MILITAEY HYGIENE. — and a too infrequent use of modern and more precise means of diagnosis, as found in the Widal test with blood-serum and the diazo reaction given by the urine. It is obvious that under many conditions of military service, particularly with marching troops, the former test can scarcely be applied, but in a fixed camp or garrison it can usually be carried out — and the technique of the diazo reaction is possible under any circumstances. These tests should be habitually applied to every case presenting fever, the nature of which is not promptly and definitely recognized as being other than typhoid. In view of the great importance of accurate and early diagnosis, even at the risk of encroaching upon the province of military medicine, these tests will be briefly considered. The Widal method of diagnosis is based upon the fact that Kviug and actively motile typhoid bacilli, when placed in the dilute serum of a pa- tient suffering from typhoid fever, within a short time lose their motility and become aggregated into clumps. For this purpose, either fresh or dried blood may be used. In the military service, the use of the latter will usually be more convenient and appears to give fully as accurate re- sults. With this method, a drop of the blood to be examined is received on a sheet of glazed writing-paper and allowed to dry in the air, and may then be folded and sent to the laboratory in an envelope. At the Army Medi- cal Museum, the fluid medium employed for the growth of the typhoid bacilli required in the test is old one per cent, glucose bouiUon. A tube of this bouillon is planted with a culture of the typhoid bacillus, which as a rule has grown on agar for several weeks. The inoculated tube is usually kept at room temperature ; since when grown for eighteen to twenty-four hours at 37° C, a loop taken from the lower part of such a tube often shows small masses of agglutinated bacilli. When grown at room temperature, the danger of previous clumping is eliminated and the baciUi are kept in good motility for three to five days. A drop of dried blood is moistened at its margin with sterilized distilled water, so as to obtain a pale straw-colored solution. This is transferred, by the loop, to the center of a clean cover-slip which has been well flamed. Generally the contents of the loops are trans- ferred, and immediately thereafter a quantity of the fluid culture, motility of which has been previously tested, is carefully mixed with the blood solution. The drop is then examined, with a dry lens, to observe motility and agglu- tination. The time adopted within which the reaction should be complete is one hour. When all motility ceases and the majority of the bacilli are gathered together in small masses, the reaction is positive. If partial ag- glutination occurs, a few bacilli are stiU motile, the reaction is incomplete and a second sample of blood is examined subsequently. When the re- action is present only to some extent around the margin of the drop, the reaction is doubtful. The relation of the dilution of the serum is very important; since if the degree of dilution be too small, a non-typhoid serum may cause clumping. If possible, examinations should be made with several dilutions ; in general, the more dilute the serum the longer the time necessary for a complete reaction. Of course an accurate measure- ment of the dilution with dried blood-serum is scarcely possible. While there is a certain small margin of error with the Widal reaction, it appears to be given by the serum in about ninety-five per cent, of aU cases of enteric fever. The reaction is usually obtainable about the seventh day of the DISEASES OF THE SOLDIER. 693 disease, though occasionally it has been found as early as the fifth day. Sometimes it has not appeared untO. the third week or later, and usually it becomes more marked as the disease advances. How long the reaction can be obtained after the end of the disease has not as yet been fully de- termined, but in many cases it has been found after several months and it probably is given after periods of years. The Ehrlich diazo reaction is given by the uriue in a large proportion of cases of typhoid fever, and possesses considerable diagnostic importance when considered with the clinical history of the case. In performing this test, two solutions, called A and B, are prepared. A consists of a twenty per cent, solution of hydrochloric acid saturated with sulphanUic acid ; B of a half per cent, solution of sodium nitrite. Immediately before using, one part of B is mixed with twenty-five parts of A, an equal volume of urine is added to it in a test-tube and strong liquor ammonia is dropped into the mixture or allowed to flow down the side of the tube. At the junction, a crimson ring forms. If the tube be shaken, the froth is colored pink; or- dinary urine gives a more or less deep orange color. In applying the test, care should be taken to mix the solution accurately. The reaction often appears before the clinical symptoms of the case are well pronounced. Since the Widal and diazo reactions may not be given at certain stages of enteric fever, they should be repeated one or more times in possibly sus- picious cases. Where typhoid fever is recognized as existing, the afifected individual should be promptly isolated. If in garrison, the clothing and bedding of the patient, together with the water-closet or latrine used by him, should be disinfected. If the case occurs under canvas these precautions are re- quired, and in addition the disinfection of the clothing and bedding of those sheltered with him should be sterilized. The tent itself should be disinfected. If possible the camp, or at least that of the company organi- zation in which the case occurred, should be moved. If this be not pos- sible, the site occupied by the tent should be vacated, policed and exposed to the sun, and should not again be occupied. In many instances it would be desirable, in addition, to freely scatter fresh lime over the entire tent area. Old tent floors should be scrubbed with a strong carbolic solu- tion, stood on edge and sunned on both sides for at least two days before being again used. Since the nature of many cases of enteric infection in camp will not be recognized, it should be the rule, under conditions of field service, to regard all human excreta as infected and, where a camp has a permanency of more than three or four days, systematically to carry out measm-es for the destruc- tion of its presumably noxious qualities. The expense of an epidemic of typhoid will be many times the additional cost of these justifiable precau- tions. In all camps of any permanency, the use of excavated latrines should be prohibited and either the trough system or crematories, as already considered, provided for the disposal of excreta. Under the same conditions, urine tubs shoidd be provided for night use and their utilization enforced. The board which investigated the epidemics of typhoid fever in 1898, found that the number of cases in the different camps varied, in a general way, with the methods of disposing of the excretions. Hence care- ful policing of the camp, with cremation of refuse, should be carried out to 694 THEOEY AND PRACTICE OF MILITARY HYGIENE. limit soil contamiriation and prevent the development of the fly plague. A careful sanitary police is highly effective in preventing the development of these insects ia very great numbers ; but where the fly plague actually exists, the only recourse is to abandon the infected area for a new site, pref- erably located to the windward and at a distance of at least two miles. The fact that a command expects to change its location at an early date does not justify neglect of proper policing of the ground occupied. Except in the case of the most urgent military necessity, one command should never be located upon a camp site recently vacated by another. Other general methods of prophylaxis consist in the allotment of abun- dant space in the arrangement of the camp ; the free exposure of the inte- rior of tents — and of their contents — ^to sunlight and air-currents ; the rais- ing of the bed of the soldier above the groimd ; cleanliness of person on the part of troops ; an abundance of good food and, in time of epidemic, the avoid- ance of exhausting drills and exercises. It is important that a presumably infected camp site should promptly be abandoned; though if troops be al- lowed first to become generally infected, this procedure is not as efficacious in controlling typhoid fever as in some other diseases. It is evident that where tents, blankets and equipage which have been infected are carried along with the troops, innumerable cultures of the bacillus are thus trans- planted to the new camp site, besides those in the bodies of the infected men themselves. With respect to the measures to be applied to prevent further spread of the infection from the sick, the proper disinfection of the excreta is of the first importance. All discharges should be received in a solution of milk of lime. The nates of the patient should be cleaned with paper and after- ward with a bit of compress-cloth wet with a dilute disinfectant solution. The bed-pan should be covered with rubber sheetiag and removed at once. In garrison, the contents of the bed-pan should be thoroughly mixed and allowed to stand for half an hour before pouring into the slop-hopper ; in the field they should be burned at once. The practice of burying typhoid discharges, after measures of disinfection by chemical means, is strongly to be deprecated. In certain instances all the baciUi will undoubtedly not be destroyed, and it has been shown that they not only develop in organically polluted ground but may grow upward to the surface through a considerable depth of earth. Even if buried deeply, there is always a possibility of then- future disturbance or of their gaining access to a neighboring water-supply. Whether in camp or garrison, the cloth compresses used to cleanse the per- son of the patient should be destroyed by fire. The bed-pan, rubber cover and slop hopper should be cleansed with disinfectant solution and the two former wiped dry. Both should be placed in a closed receptacle to prevent access by flies when not in use. AH sputum should be received in spit- cups containing a disinfectant solution. Feeding utensils should be cleansed with boiling water immediately after use, and any uneaten rem- nants of food at once disinfected by burning or scalding. All bed-linen, body-clothes and towels soiled by discharges should be immediately rolled in a clean sheet wet in bichloride solution and removed for appro- priate disinfection. Bed-spreads and blankets should be sunned and aired as often as possible. They should not be shaken in the sick-room any more than is absolutely necessary. Bed and body-linen should be changed DISEASES OE THE SOLDIEE. 695 daily and all soiled linen should at once be disinfected; rubber sheets should be used over the mattresses. Flies should be kept away from the patient, not only for his comfort but to prevent the transmission of his disease to others by their agency. After attending to the wants of a typhoid patient, the hands of the nurse in each instance should be rinsed in a disinfectant solution and then washed in warm water, using soap and a nail-brush. The urine of patients convalescent from this disease should be ex- amined at frequent intervals for the typhoid bacillus, and return to duty or quarters before this bacillus has been absent from the urine for a period of at least one week should not be permitted. To effect the sterilization of the urine, when this bacillus is present, Eichardson and others recommend the use of urotropin, in ten-gr^in doses, three times a day. Salol and other substances appear to have little value for this purpose. The return of typhoid patients to their regiments for convalescence in order to make room in possibly crowded hospitals is above all to be avoided. Preventive Inoculation. — The problem of preventive iaoculation against typhoid fever, now receiving much attention, has a special impor- tance for the military sanitarian. Bokenham endeavored to produce a pro- phylactic and curative serum by the immunization of horses through the repeated injection of living and dead cultures of the bacillus; but the serum thus obtained was not of sufficiently great potency to give it a prac- tical value, and no means could be found of precipitating or concentrating what strength the serum contained. Pfeiffer, Wright and Semple and others then endeavored directly to produce in man the immunity which it was shown could be created in animals. At first these investigators cul- tivated virulent cultures on agar, making up an emulsion of these cultures with bouillon so that each cubic centimeter contained about 2 mgm. of fresh agar growth. The microbes were then kOled by exposure to a tem- perature of 56° C. for several hours. Of this emulsion, 1 c.c. was used as a dose, the liquid being well shaken. Eecently Wright has attained more satisfactory results by cultivating the bacilli directly in ■ bouillon. After incubation at 37° C. for a period of fourteen to twenty-one days, the cul- ture is sterOized by exposure to a temperature of 60° C. for five minutes. This is done by drawing the emulsion into smaU sterile tubes, which are sealed and placed in a beaker of cold water which is gradually raised to the desired temperature, and this is maintained for the period above noted. Agar tubes are then inoculated with the material to make sure of its ster- ility. Before injection, one-half per cent, of lysol is sometimes added to neutralize any accidental contamination. The amount used for human inoculation is two-fifths of the minimum amount which would be fatal to a guinea-pig weighing 250 gm. The immunizing material appears to be valuable rather on account of its antimicrobic than its antitoxic proper- ties. While the reaction following the inoculation is usually slight, it is at times somewhat severe. Eigors, nausea and a tendency to syncope some- times occur. There is a well-marked local reaction, which, however, never advances to suppuration. When the inoculation is successful, the blood- serum acquires the specific agglutinative property with regard to the bacilli to a marked degree. Cameron found in his own case that at the end of 696 THEORY AND PEACTICE OF MILITARY HYGIENE. twenty days the agglutinating power of his blood-serum was increased forty times ; and an increase to this extent has been shown by other observers commonly to result. In general, the agglutinating property is equal to that conferred by an attack of the disease itself. It is not known how long the influence of the inoculation persists ; and when a protection lasting more than two years is desired, it is recommended to ensure a good reaction by repeating the inoculation after an interval of one week. This repetition appears to be of importance in secmring the best results. At present, experience with these inoculations has not been sufficiently comprehensive to warrant the drawing of exact conclusions. The inocula- tions have been carried out on a considerable scale, however, with the sanction of the military authorities, on British soldiers voluntarily submit- ting to the operation before leaving for the recent scene of hostilities in South Africa. Foulerton states that reports so far received from the Anglo- Boer War show that typhoid fever has occurred at the rate of six to the thou- sand among the inoculated and nine to the thousand of the uninoculated. Figures given by Wright, based upon 11,295 inoculated British soldiers in India, show that .95 per cent, of these contracted the disease where 2.5 per cent, of the uninoculated were attacked. These results, while not brilliant, are certainly encouraging and render the method well worthy pf general use among young soldiers detailed for tropical service ; particularly since the inoculation, when properly performed, is quite free from actual danger. Influenza. Occurrence. — In the military service, influenza is chiefly of impor- tance through the incapacity for duty which it produces. The military age does not include the extremes of life, at which the disease is most fatal, and hence the mortality directly resulting from this affection is small; but that it exerts a certain unfavorable influence in the production of secondary pneumonia and tuberculosis there can be no doubt. The disease in our army has occurred in well-defined epidemics, of great in- tensity but short duration. During recent years these epidemics have occurred with much greater frequency. Following their subsidence, there appears to have been a tendency on the part of medical officers to confound simple respiratory catarrhs with this disease, even in the absence of any epidemic tendencies — thus probably unduly raising the rates for this affection. During the Civil War, the admission rates for influenza, per thousand strength, amounted to 60.84. For the sixteen years 1868-84, the cases fell to an average of 9.39 per thousand strength. During the decade 1885-94, epidemics in 1892 and 1893 raised the figures for this disease, making the admissions 49.88 per thousand strength. For the period 1895-98, the admission rate was 44.92. For the year 1897, the admissions were again increased to 74.35, while for 1898 they fell to 32.37. In foreign armies, the disease has prevailed among troops during the general epidemics which have from time to time occurred. In 1892 and 1893, high rates for this disease were given in all European armies. In the British army the disease has prevailed nearly every year since 1889. In the Eussian service, influenza appears annually as a potent factor in elevating the sick rates. DISEASES OF THE SOLDIEE. 697 (After Cause. — The disease is now generally accepted as being produced by- specific bacUli which, as seen in the sputum, appear as very minute rods, staining more deeply at the extremities. These bacilli occur singly or form clumps by their aggregation, but do not grow into chains. They show no capsule, are non-motQe and do not form spores. They take up basic aniline stains somewhat feebly and are best stained with carbol-fuchsin. They are decolorized by Gram's method of staining. The bacilli grow best at body temperature and upon the surface of media containing blood or blood-coloring matter, the latter appearing to afford substances especially adapted to the nutrition of this micro-organism. After twenty-four hours, the colonies appear as minute circular, transpareiit dots. The bacilli die out very quickly ia cultures. A small amount of growth takes place in bouil- lon to which a little fresh blood has been added. Dissemination and Infection. — The powers of resistance of this ba- cillus appear to be of a very low order. Pfeiffer found that dried cultures kept at the ordinary temperature were usu- ally dead in twenty hours, and that no growth could be obtained from influ- enza sputum at the end of two days. Their duration of life in ordinary water is also short, the baciUi being usually dead in two days. From these experiments, Pfeiffer concludes that the bacilli cannot multiply under ordinary condition outside the body, and can remain alive for a short time only. The mode of infection ia the disease he accordingly considers to be chiefly by direct contact with infective mu- cus, with which alone the bacilli probably escape from the organism. Its rapid spread over large areas was long thought to be explainable on the supposition that the infection was air-borne, but this is probably due to the combined effect of a short incubation period, an early infectiveness, a gen- eral susceptibility and the existence of early unrecognized cases. It is im- possible to state exactly the conditions which favor its development and spread, but atmospheric conditions which favor bronchial irritation certainly play a part. The incubation period is from two to six days, and perhaps at times the limits are wider. Infectivity is established early, in many instan- ces before the disease has fairly declared itself. It persists for some time after acute symptoms have subsided, judgiag by the presence of Pfeiffer' s bacillus. While this micro-organism appears to be unable to cause influ- enza in the lower animals, there is abundant evidence that certain animals suffer with symptoms much like those of influenza during epidemics of this disease. During the severe epidemics of 1892 and 1893, the disease known as "pink-eye," regarded by many as a form of influenza, was ex- tremely prevalent among our cavalry horses. Prophylaxis. — Influenza is an iafectious disease, the spread of which can be checked by isolation ; but when the peculiar features of the disease and the conditions of military life are considered, it must be admitted that Fig. 338.— Influenza Bacilli In Sputum. Abbott.) 698 THEORY AND PRACTICE OF MILITARY HYGIENE. isolation has its limitations and can usually only mitigate but not entirely prevent an epidemic. In general, however, it is important to prevent as far as possible the contact of the infected with the uninfected. Soldiers affected with the disease even in a mild form should be taken into hospital, not so much for their own welfare as for the sake of others. While the disease prevails, large assemblages of troops should, as far as possible, be avoided. There should also be an avoidance of all influences that lower the general tone, and good ventilation with cleanliness of person and sur- roundings are of value. The sputum of affected individuals should be treated in the same manner as if it were tuberculous. AU handkerchiefs, napkias, bedding, clothing and other articles used by the sick should be disiafected — though when an epidemic is once established, the infection is usually so widespread that measures looking to the control of the disease are of but little avail. Malarial Fevers. Occurrence.^ — Malaria has ravaged armies in every age and climate, and has frequently modified military operations or brought about their failure. Rome was saved from capture by malarial fevers, which so scourged the besieging Gauls under Brennus as to cause their retreat. In the year 208, the Roman army in Scotland lost 50,000 men out of a total of 80,000 from this cause. No military disaster caused by malarial in- fection was more complete, however, than that of the British expedition to the island of Walcheren, ia 1809. On this occasion it has been said that the British were conquered before the battle. Out of an effective force of 39,219 there succumbed to the fever, between August 28th and December, no less than 23,175 men, while after the return to England there were 11,503 additional cases. But 217 men, during this disastrous expedition, were kUled by the enemy. In the Seminole War, in Florida, our troops suffered severely from malarial infections. In the French army before Sebastopol there were 20,623 cases with 2,179 deaths. In the Union forces, during the Civil War, there were 1,314,744 cases of malaria with 10,062 deaths; giving a mortality of 3.92 per thousand strength. " But though the mortality from theSe fevers was comparatively light, their influence in detracting from the efficiency of the army was very great " — as well as largely influencing the rates of discharge for disability on ac- count of resulting ansemia and chronic malarial poisoning. The so-called " Chickahominy fever " was particularly severe in its effects. Malarial fe- vers prevailed in the French army during the Italian War and the occupa- tion of the Papal States. Ash mead states that 5,995 Japanese soldiers, sent to Formosa in 1873, furnished 6,105 admissions to hospital, for continued malarial fevers, in a single year. In the French expedition in Madagascar, in 1895, out of a force of 22,850 men — combatants and carriers — there were 7,498 deaths from disease; a mortality of about 33 per cent. Nearly all the deaths were from malarial fevers. During this expedition only 7 men were killed by the enemy and but 94 wounded. In the same year, a Spanish expedition in the I'hihppine Islands was scourged by malarial fever. Durmg the last insurrection in Cuba, the Spanish f(jrces were largely depleted by malarial infections of a severe type ; the admissions to hospital for this cause, during the year 1897, amounting to 420 per thou- DISEASES OP THE SOLDIER. 699 sand strength. In 1898, after the capture of Santiago, one-half of our forces in Cuba were incapacitated for duty at the same time by reason of malarial fevers. This grave condition of affairs evoked an appeal to the War Department, signed by all the officers of higher rank, for an immediate removal of these troops to a more healthy locality — using the sentence : "This army must be moved or perish." Until within a comparatively recent period, malarial disease, in time of peace, constituted the prime factor in the constitution of the sick reports of our army. To-day, except for a few posts, it occupies a minor position for troops on the home station — ^the decrease not only having been great but steadily progressive. This reduction has been brought about by the with- drawal of troops from more unhealthful stations and by greater attention to sanitary detail at the few malarious posts at which military necessity re- quires garrisons to be maintained. During the last quarter of a century. 1 ^:riiiiiiiiiiiiiiiniiiiiiiiiii^ii^iii *fr . - . . ^ . sso ^-,- '* \ 6o ] 1 ""■■■f - 5^ ..S VM ^ .-- ',„ i=> .i^..^.,.. = :: -. li3D,— Chart Showing Admissions for Malarial Infections In the United States Army, per Thousand Strength, for the Period 1861-98, Excluding the Year 1867. also, the disease appears to have decreased considerably in frequency, especially in the eastern portion of the United States. The possibility of retaining troops at stations on the Potomac Eiver, as an example, was long a matter for serious consideration. Nearly all the garrison at Fort M}'cr contractetl malarial fevers during the season; of Washington Bar- racks it was at one time officially reported that during the malarial months there were scarcely enough well men to perform guard duty ; and at Fort Washington tlie prevalence of malarial disease resulted in the abandon- ment of the post as a station for troops. These posts stiU lead aU other military stations in this country as regards malaria, but the proportionate number of cases of malarial infection is now very gi'eatly reduced. Follow- ing the re-garrisoning of Fort Washington, the sick rates at that station have been by no means seriously high. Since the Civil War, the admissions for malaria for the entii-e army, per thousand strength, fell fi'om 793.75 in 1868 to 78.88 in 1897. For the period 181)8-84, the admission rates, per thousand strength, amounted to 331.06; for the decade 1885-94 they were 92.27. The influence of war. 700 THEOEY AND PEACTICE OF MILITAEY HYGIENE. and especially the exposure to malarial infection in the tropics, caused an increase in the admission rate to 694.60 in 1898. The death rate, also, was unusually high during the last-named year, showing the more grave nature of the tropical infections. The board iavestigating the occurrence of typhoid fever during the war with Spain came to the conclusion, how- ever, that malaria was a comparatively rare disease among those soldiers who remained within the limits of the United States. As great as has been the reduction of malarial disease in our own army — to one-tenth of its prevalence a generation ago — ^the improvement in this respect in the German service has been even greater. Official figures for that army are as follows : „ . , Admissions Verioi. per 1,000 strength. 1881-83 to 1885-86 14.3 1886-87 to 1890-91 4.1 1891-93 to 1895-96 1.1 Year 1895-96 55 Year 1896-97 45 In the French army, the admissions for malaria, per thousand strength, are thus given by Coustan for troops in Prance and Algeria. Admissions Period. per 1,000 strength. 1875-79 30 1880 18 1881 25 1883 30 1883 56 1884 15 1885 20 For the British forces on the home stations, the admissions for the decade 1888-97, per thousand strength, amounted to 6.3; for the year 1898 they were increased to 9.5. In the Eussian army, the admission and mortality rates from malarial fevers, per thousand strength, were lately as follows : Period. 1888 Admissions per 1,000 strength 13 1889 16 1890 17 1891 36.1 1893 34.4 1893 14.3 Year. Admissions. Deaths. Tear. Admissions. Deattis. 1890 103.3 79.9 78.1 79.1 7.1 .05 .08 .07 1894 1895 57.6 44.5 46.5 47.3 08 1891 06 1893 1896 08 1893. . 1897 07 In the Austrian army the cases of malaria amounted to 50.3 per thou- sand in 1885 ; to 30.6 in 1891 ; to 40.4 in 1892 ; to 34.7 in 1893 ; to 28 in 1894; to 26.1 in 1895; to 22.6 in 1896; and to 31.9 in 1897. The deaths from malaria in the Italian army, per thousand strength, have re- cently been as follows : Year. 1893. 1894. 1895. Death rate. .. 0.13 .. .10 .. .12 Year. 1896, 1897. Death rate. .. 0.13 .. .08 Cause. — The organism now recognized as being the causative agent in the production of malarial fever is an animal parasite discovered by Lave- ran, of the French army, belonging to the protozoa and known under the DISEASES OF THE SOLDIER. 701 name of Plasmodium malariae. Eegarding the invariable presence of this organism in the blood of those sick with the disease, and the cycle of changes which it undergoes in relation to the paroxysms of fever, all are agreed. On the other hand, some doubt still prevails regarding certain periods of development, and especially regarding the number of varieties of the organism and their relations to one another. The view entertained by Laveran is that there is but one species of malarial parasite, which is poly- morphous and presents slight differences in structural character in the different types of fever. This view, however, is held by but a small mi- nority of observers. There is now a fairly general agreement as to the division of the varieties of malarial fever, according to the character of the parasite, into two main classes ; the first including the milder forms, tertian and quartan, and the second including the quotidian, malignant or ffistivo- autumnal and certain irregular forms. In all these types of fever the para- sites pass through a definite cycle of development, which is complete in a period of time corresponding to the variety of the fever. The parasites are always most abimdant in the blood during the attack of fever, but in the intervals they may become greatly diminished in number or even disap- pear. They are also, as a rule, more abundant in the internal organs than in the peripheral blood-vessels, and in some types of fever the process of sporulation is practically confined to the former. In general, the life history of the parasite in the blood of man is briefly as follows : The spores are the youngest and smallest forms, which result from the segmentation of the adult parasite. They are rounded or oval protoplasmic bodies, varying in size with the different types of fever and possessing lit- tle or no amoeboid movement. They remain free in the serum for a short time, but soon attack the red blood corpuscles and become the intra-corpus- cular amoeboid bodies. This invasion of the blood cells by the immature parasites, while it has not actually been witnessed, may be safely assumed to occur. As intra-corpuscular bodies they usually occur singly in the blood cell, but sometimes several may be present together. The youngest forms ap- pear as minute colorless specks; as seen in the fresh blood they exhibit amoeboid movement and show marked variation in shape, the amount and character of the movement varying with the type of the fever. As these bodies increase in size they become gradually pigmented with dark brown or black specks. The pigment may be scattered through their substance or be concentrated at one or more points, and often shows vibratory move- ment. The red corpuscles invaded may remain unaltered in appearance or may be either swollen or shrunken. Sometimes, namely in the quotid- ian and malignant fevers, the parasite passes into a quiescent ring form, showing in this condition a well-defined outer circular margin, the pigment being usually collected in a small clump at one side. These ring forms may again assume amoeboid movement. Within the red corpuscle the parasite gradually increases in size until the full adult form is reached, when the parasite loses its amoeboid movement more or less completely, has a somewhat rounded form and contains a considerable amount of pig- ment. The adult parasites may then undergo segmentation, but not all of them do so — many become degenerated and ultimately break down. 702 THEOEY AND PRACTICE OP MILITARY HYGIENE. In the process of segmentation or sporulation, the pigment becomes col- lected into a small central mass ; and from it, as a center, lines radiate and divide the protoplasm into regular segments, produciag a characteristic rosette appearance. The segments or spores thus formed vary in number and size in different types of fever. They are more or less rounded ia shape and are set free in the blood plasma. The pigment granules remain apart from the spores, sometimes surrounded by a portion of the substance of the parasite, and are chiefly taken up by leucocytes. The process of segmentation, however, does not occur in all forms of malarial Fig. 340.— Dried Blooa-Films Showing Malarial Parasites, Magnifled About 1,000 Diameters. A, Early in- tracorpuscular form ot tertian parasite ; B, large intracorpuscular form of same parasite, showing scattered pigment granules, with enlargement ot invaded corpuscle ; C, two members of the rosette series of the same parasite, with early and radiate segmentation ; D, two ring-forms of the quotidian parasite ; E, crescentic body ; F, flagellated organism, derived outside the body from a cresceuHc form. (After Muir and Ritchie.) fever in this radiate fashion, but ia some it takes place more or less irregu- larly. In addition to the forms which appear to constitute stages in this regu- lar cycle of development withia the body, there are two others, the cres- centic and flagellated organisms. The first-named organisms are non-amoeboid, and are of crescentic or sausage shape. Occasionally a fine curved line is seen joining the extrem- ities on their concave aspect, which probably represents the remains of a red corpuscle. They are colorless and transparent, have a distinct and en- closing membrane, and usually show a small collection of granular pigment about their middle. These crescentic bodies are usually regarded as result- ing from the fusion of the intracorpuscular bodies. They are not found in aU types of the fever, but occur especially in the quotidian and astivo- autumnal types, and apparently do not represent a stage in the ordinary DISEASES OF THE SOLDIEK. 703 cycle of development. They appear in the blood after the fever has lasted for some time, apparently remain unchanged through attacks of pyrexia, and may persist after the fever has gone — being often present in the cachexia or anaemia following these fevers. If a drop of blood be examined under the microscope for some time, flagellated organisms may be found. Su far as Icnown, these do not occur as such in the circulating blood, but appear only in blood outside the body. They are derived either from the crescents or from the larger pigmented intra-corpuscular bodies. Muir and Eitchie state that in the former case the crescents alter their shape; becoming straight, oval and ultimately spherical. The pigment granules first become arranged as a ring, and after- ward show a peculiar vibratory movement that is apparently produced by flagella which have formed within the sphere. When this stage is reached, the flagella, usually three or four though sometimes more, are pro- truded through the envelope and present a rapid lashing action. The fla- gella are very delicate filaments with sometimes a slight bulbous swelling at the free extremity. They may afterward become detached and move away with an active independent movement. In the case of their devel- opment from the large intra-corpuscular bodies, the pigment shows an agi- tated movement in the same way, and ultimately the flagella are protruded. There has been, and is, great diversity of opinion concerning the nature of the crescentic and flagellated bodies. The view most generally accepted is that the former represent a sort of resting form for the life of the malarial organism outside of the body, the first stage of which is the flagellated condi- tion. The view has been advanced that the flagella are really flagellated spores which undergo further change, and that this probably occurs in suctorial insects which have taken up blood containing the parasite ; and Eoss has found that in the stomach of the mosquito many of the crescents become spherical and develop into flagellated forms. The principal differentiating characteristics of the different varieties of the parasite may be enumerated as follows : In the quartan type of infection the parasite passes through its cycle of development in three days, and all the various stages are found in the blood. Only the smaller forms within the red corpuscles show amoeboid movements, and these are not of a very active character. The red corpus- cles invaded by the parasite do not become decolorized or altered in size, and the pigment granules, are somewhat coarse. Typical rosette forms are seen in the process of sporulation, which results in the formation of six to twelve segments or spores. In fresh blood, these spores show a central clear spot which is not seen ia the spores of the tertian parasite. In the tertian form, the cycle of development of the parasite is com- pleted in forty-eight hours. The young forms within the red corpuscles show much more active movement than in the quartan type and give off longer and more slender processes, while the pigment granules are finer. The invaded corpuscles are pale and swollen. Sporulation, resulting in the formation of from fifteen to twenty round spores, takes place by means of a rosette or sunflower formation, the lines of segmentation being at the periphery and a portion remaiaing aroimd the central collection of pigment. In the quotidian form, most commonly observed in the tropics, the cycle of development is complete in twenty -four hours. Within the red 704 THEORY AND PRACTICE OF MILITARY HYGIENE. corpuscle the parasite is of small size, and even in its adult condition, im- mediately before sporulation, it does not usually occupy more than a third of the corpuscle. The amoeboid forms often pass into the ring form already described. In the course of their development they acquire a very fine dust-like pigment, and in the adult quiescent form the pigment becomes collected into a small dark body. The spores, usually six or eight in num- ber, are formed by irregular segmentation and are very minute. The process of sporulation takes place almost exclusively in the internal organs, and as a rule sporulating forms are not observed in the peripheral blood. In the malignant or aestivo-autumnal type of the fever the parasite closely resembles that of the quotidian. Its cycle of development, how- ever, apparently occupies forty-eight hours, and the young parasite may be without pigment for twenty-four hours. The malignant parasites do not mature in groups, but independently as it were — ^parasites in aU stages of development being met with in the same specimen. The amoeboid ac- tivity is manifested even ia the adult pigmented forms. In this variety of fever ring forms frequently occur. In the quotidian and aestivo-autumnal varieties, the red corpuscles in- vaded have a tendency to shrivel and assume a deeper or coppery tint. When a fatal result occurs, large numbers of parasites, many in process of segmentation, may be found ia the braia and internal organs. In some fatal cases, with coma, the cerebral capillaries may appear to be almost filled with them. Irregular types of fever, sometimes of continued character, may be in- duced by infection with different generations of the same variety of para- site, or by infection with different varieties. Though the malarial parasites have not been cultivated on artificial media, the evidence that they are the cause of the disease is conclusive. They are always present in the affection and are foimd in no condition apart from malaria. Their cycle of development also corresponds in a remarkable manner with the course of the fever, each febrUe attack being accompanied by the appearance of a new generation of parasites in the blood. In all probability the fever is produced by toxic bodies set free by the young parasites, but this point is scarcely susceptible of proof. The presence of the parasites in the red blood corpuscles, and the destruction of substance which takes place in the latter, explain the occur- rence of the anaemia which so often results ; and the subsequent distribu- tion and storage of the altered haemoglobin, obtained in the destruction of the red corpuscles, explain the pigmentary changes in the various organs. As repeatedly shown by experiment, the disease can be communicated from one person to another by injecting blood containing the parasites ; infection occurring most certainly when the injection is intravenous. In such cases there is an incubation period of from seven to fourteen days before the fever occurs ; the same type of disease being reproduced as was present in the patient from whom the blood was taken. Eecent experiments have demonstrated that the disease may be transmitted from an infected to a healthy individual through the agency of the mosquito. It may be men- tioned that in certain affections of birds and reptiles, parasites of somewhat similar character to those in malaria, but of distinct species, occur in the blood. Artificial injection of blood from an infected bird into a healthy DISEASES OE THE SOLDIER. 705 one invariably produces the disease ; and the same occurs when mosquitoes which have sucked the blood of diseased birds are allowed to bite healthy ones. In fact, in the latter case, the inunature forms of the infecting agent have been directly traced to the salivary glands in these insects. Manner of Infection. — Since the malarial parasite has not been ob- served outside the body, and nothing is known concerning its extra-corpo- real existence, it is impossible to speak with certainty as to aU the modes of its entry into the system. The latter very probably occurs in several ways. It has recently been advanced by some that the disease is transmitted from man to man only by direct inoculation, the mosquito serving as the inter- mediate host and agent by which infection is brought about. This claim, however, clearly lacks substantiation. It is a matter of common observa- tion that the infecting organism of malaria must be able to multiply indefi- nitely outside the body independently of man; in fact, malaria is most prevalent where man is not — and where human beings, through the preva- lence of this disease, cannot maintain an existence. Therefore this extra- corporeal multiplication must demand something more than a short cycle from man to mosquito and mosquito to man. Where this extra-corporeal life of the malarial parasite is spent has not yet been scientifically demon- strated, but both analogy and common experience point to water as neces- sary to its existence. As already shown, the parasite in the blood is poly- morphous and in the flagellated variety presents a type well fitted to pursue an independent existence. In water it may perhaps assume other and un- known forms capable under certain conditions of directly invading the organ- ism thrcagh the walls of the alimentary tract. Certainly this is possible to other somewhat similar forms of life, as in dysentery,- and there is much evidence of a practical nature to show that a malarial infection may actu- ally be contracted in this way. Both Manson and Laveran believe that drinking-water in which iqfected mosquitoes have died may cause the dis- ease, and under such conditions a large number of active flagellated organisms are undoubtedly deposited in the water. Military history is full of instances in which outbreaks of malarial fever have occurred apparently as a result of the use of impure marsh-water, and under circumstances which leave little possibility for infection by other means. As a type of these examples may be mentioned the outbreak of malaria on the ship Argo, detailed on page 115, and, like other similar instances, never yet disproved. Fur- ther, military history presents many cases in which the rates for malarial fevers have been greatly diminished on the substitution of a pure for an impure water-supply. In our own service, the following instances may be mentioned : Port Brown, in 1889, had an admission rate for malarial fevers of 1,675.86 per thousand strength, with a rate of 38.58 for constant sick- ness from this cause. Distilled water from the ice-machine was then pro- vided for the use of the troops, and the rates for 1891 became 325.91 and 8.32 respectively. In 1 8S 2 the admission rates had fallen to 1 6 . 1 3 per thou- sand strength and the constant sickness to .35. The rates for this post have never returned to even a small fraction of what they were before the intro- duction of distilled water, and Fort Brown has ceased to be regarded as one of the most malarious stations in the army. At Fort Einggold the admis- sions for malarial fever, in the year 1885, amounted to 2,304 per thousand strength. Distilled water was supplied for the use of the troops, though its 45 706 THEOEY AND PRACTICE OE MILITAEY HYGIENE. exclusive use was not compulsory, and in 1889 the rates had fallen to 562 per thousand strength. At this time considerable field service was performed by the troops stationed at Fort Einggold, and the post surgeon reported his belief that every case of malarial fever could be traced to an infection acquired outside the post. In 1897, the admissions for malarial fever at Fort Einggold amounted to but 89.42 per thousand strength. In the experience of the writer, the soldiers at Jefferson Barracks were severely affected with malarial fevers; while after the iutroduction of boiled water a marked reduction in these" affections was apparent. Among the officers and their families at this station, who were careful to drink boiled or imported spriDg-waters only, not a case occurred save in two children who were shown to drink habitually water from impure and unauthorised sources. Later, at Washiugton Barracks, it was observed that among the men composing two batteries of artillery, who drank unfiltered water, the proportion of malarial cases was four times as great as among the men of the Hospital Corps Company of Instruction, having an average strength of about one hundred and fifty men, who drank only water passed through Berkefeld filters. Such instances as the above may be largely multiplied, and serve to emphasize the fact that, however else the malarial organism may gain access to the system, its entrance by means of the water-supply should never be disregarded by the mUitary sanitarian. Grawitz has recently shown, in con- nection with the occurrence of malaria through inoculation by mosquitoes, that the disease is most common in the German army during spring, when mosquitoes are not especially active ; and he regards a water-supply above "re- proach as a necessity in preventing malaria. It is true that a number of experiments have been made ia the attempt to cause malarial infection by way of the alimentary tract. Healthy persons have been allowed to drink the water from supposedly malarious marshes; enemata of similar waters have been given to other individuals, and even the blood of malarial patients has been drunk by uninfected persons. These experiments were negative in their results. In the absence of positive knowledge that the water contained malarial organisms in the proper stage of development, the first experiments prove nothing; as for the experiment with the infected blood it may well be that in this intra-corporeal stage the parasite has little powers of resist- ance against the digestive juices. In the light of the instances above quoted, it may fairly be assumed that some important factor present in natural infection was inadvertently omitted from the experiment. On the other hand, besides abundant experimental evidence to the contrary, the theory that malaria is transmitted by water alone is refuted by the fact that men on board ships, anchored off a malarial coast, who may not have been on shore and have used nothing but distilled water, often contract the disease. There is a very general impression that infection can occur through the respiratory tract, though in the absence of knowledge concern- ing the life of the malarial parasite outside of the body it is evident that this point is not susceptible of absolute proof. Sleeping on the ground, where the emanations of a malarious soil are inhaled during repose, has long been thought to favor the prevalence of the disease among soldiers. It should not be forgotten in this connection, however, that a wind which serves to carry a so-called malarial miasm may also carry insects serving as hosts for malarial parasites, that the period of activity of these insects DISEASES OE THE SOLDIEE. 707 is at night and that they are much more numerous near the level of the ground. As a result of modem iuvestigation, the occurrence of the disease through inoculation by infected mosquitoes has been scientifically demon- strated, and it appears certain that the organism frequently gains access to the blood in this manner. It has not, however, been shown that mos- quitoes in a known malarial district harbor this parasite except after suck- ing the blood of an infected individual; and what part they play, if any, in the origination of the first cases of the disease occurring in individuals penetrating a previously uninhabited region has not as yet been worked out. It may be that the malarial organisms present in water have the power of entering into the malarial mosquito during its period of develop- ment in water in the larval stage, and thus some of these insects may be capable of conveying the infection as soon as they arrive at adult form, without necessarily having sucked blood from individuals affected with malaria. That healthy persons may be directly inoculated by mosquitoes which have sucked the blood of a diseased individual there is no doubt. Careful research has shown that, be- ginning in the stomach as an or- ganism sucked up in the infected blood, the malarial parasite embeds itself in the stomach wall as a round, pigmented body, works its way through the successive coats of the viscus until it comes to lie under the outer layer, and finally bulges into the body cavity. By this time, its bulk has been so greatly increased by the repeated fragmentation of its nucleus and consequent enlargement of its contents, that it has become con- verted practically into a huge spore-bag fuU of little rod-like spores. The outer membrane ruptures and the spores are set free in the tissues, to find their way ultimately, in an as yet imexplained manner, into the salivary or venom glands. Here they crowd the acini in myriads, to be discharged into the blood of the human being during the process of biting and there to begin a new stage of development. While the mosquito then may transmit a malarial infection, it appears to be equally as definitely proved that only mosquitoes of a certain kind do so, and that many varieties of these insects play no part in the occur- rence of malaria in the human being. So far, the genus Anopheles alone has been shown by Eoss, of the British army, to transmit the disease; there being of this genus three recognized species native to North America, whUe a large number of varieties are found in the tropics. The far more common Culex is not at all concerned in the transmission of malaria. The differentiation between the malaria-bearing and the harmless mosquito is not difficult, even to inexperienced eyes. Anopheles has a smaller head Kg. 341.— Anoplieles Punctipennis, Female, with Male Antennae at BlRht, and Wing Tip Showing Venation at Lett, mucli enlarged. (Alter Howard.) 708 THEORY AND PRACTICE OE MILITARY HYGIENE. Fig. 342.— Culex Taenlorhynchus, Female Showing the Short Palpi which Distinguish Culex from .Anophe- les. Toothed front tarsal claw at right, much en- larged. (After Howard.) than Culex, while the palpi are much longer than in the latter insect, nearly equalling the length of the proboscis. The front tarsal claw of Culex is toothed, while that of Anopheles is not. Another striking difference is that in Anopheles the wings generally have several large spots along the anterior edge, while in Culex the wings are ordinarily plain. Eoss says that this differ- ence holds good in all the mosqui- toes seen by him — but there are nevertheless some known species of Anopheles without spotted wings and some known species of Culex with them. The attitudes assumed by these mosquitoes, when sitting on a wall, according to Ross, is characteristic ; but Howard found, for this country, that this position holds good only where the mosquito is resting on the ceiling. Anopheles holds its body almost at right angles to the surface on which it sits, its proboscis prolonging the long axis of the body. Culex, on the contrary, carries its body and proboscis parallel to the surface on which it rests. Whatever the attitude assumed by Anopheles, it is all in one line ; while that of Culex is invariably angular or hump-backed. In the resting condition, the two insects can therefore be differentiated at a glance. It is said by Howard that the note made by Anopheles is several tones lower than that of Culex. The life history of Anopheles has not yet been entirely worked out, but probably differs to no great extent from that of Culex. The eggs of the latter insect are laid in water, usually in boat-shaped masses, though various forms are assumed. The most com- mon form is that of a pointed el- lipse, all the eggs perpendicular, in six to thirteen rows and with three or four to forty eggs in a row. The number of eggs in each mass varies from two hundred to four hundred. As seen from above, the egg-mass is grayish-brown; from below, sil- very-white. The eggs hatch, un- der favorable conditions, in about sixteen hours. The darker colored egg-mass of Anopheles is laid loosely on the surface of the water, each egg lying on its side instead of the end. They are not attached to each other, but naturally float closely together. About forty to one hundred eggs constitute an egg-mass ; these hatching in three or four days. Gray was able to raise Anopheles from sun-dried mud and marsh-grass, from which he concludes that the eggs of this species are capable of resisting a considerable amount of drying. In the larval condi- FIG. 343.— Eestlng Positions of Culex (at left) and Anopheles (at right). (After Ross.) DISEASES OF THE SOLDIER. 709 Fig. 344. -Egg-mass of Culex, greatly enlarged. (After Howard.) tion, the two insects are readily distinguished from each other. The Jarvte of Culex iloat heads downward near the surface of the water but nearly at right angles to it, with the respiratory tube opening at the exact surface. When disturbed, they wriggle down to the bottom of fhe pool. The lar- vae of Anopheles, on the other hand, float flat on the surface like sticks, and when disturbed wriggle on the surface with a backward skating movement — though if much dis- turbed they may subsequently sink. The larvae of both Culex and Anoph- eles are readily drowned when forced to remain below the surface, or when agitation of the water interferes with their supply of air. The color of An- opheles larvae is dark, nearly black ; those of Culex are light gray or faintly yellowish. The larvae of Culex appear to be found almost entirely in artifi- cial collections of water, as in tubs, pots, broken bottles, cisterns or drains ; the larvae of Anopheles are almost always found in natural collections of water, chiefly raiu-water puddles which do not dry up too quickly, which do not contain fish and are not liable to be scoured out by heavy rains. Puddles containing algae are usually preferred, since the larvae of Anopheles have been shown to subsist largely upon this vegetable growth. After a minimum of about seven or eight days for Culex, and about twelve to sixteen days for Anopheles, the larvae develop into pupae; these differ from the larvae in the great swelling of the thoracic segments. In general, the adult Culex issues from the pupa after about two days. Anopheles in five days. The female begins to deposit eggs shortly after- ward, giving about ten days as a minimum for the completion of the cycle with Culex, and about twenty-four days for Anopheles — ^but the rapidity of development of both species varies greatly with the weather. The mos- quito is not a short-lived insect, as is generally supposed, but may live for months and habitually hibernates during the winter sea- son. Anopheles is said to bite almost entirely at night, passing the day in ardormant state in which it may be readUy caught or destroyed. So far as known, this variety has not been found at an altitude of more than 1,500 feet. Mosquitoes can scarcely fly against the wind, and usu- ally drift with the air-currents. Bignami invites atten- tion to the fact that the precautions taken by natives of malarious countries against infection with this disease are always equally efficacious against the attacks of mosquitoes. Predisposing Causes. — Excluded from the Arctic zone, malaria ap- pears to increase in frequency and virulence as the equator is approached ; but this progression lacks both constancy and uniformity and does not exactly correspond with the isothermal lines. Certain tropical countries. Fig. 345.— Toung Larvse of Culex Pnngens, greatly enlarged. (After Howard.) Fig. 346.— Pupa of Culex Pungens, enlarged. 710 THEORY AND PEACTICE OF MILITARY HYGIENE. like Australia and New Caledonia, are free from malaria. , It has recently been imported into the island of Eeunion by troops returned from the Madagascar expedition, and now, according to Manson, causes one-third of the entire deaths. In general, however, the disease bears a close rela- tionship to warm climates, and of late years a high mortality from malaria has occurred only in the tropics. In this country, the present rates for mala- rial disease are greatest among troops stationed in the southwest and in the Mississippi basin, although the few posts on the Potomac Eiver are notori- ously malarial. During the Civil War, statistics gathered by the sanitary commission showed the number sick from malaria, per thousand, to be proportioned as fol- lows : In northern posts at a distance from the sea and Great Lakes, 151 ; in the lake region, 193 ; at seaboard stations, Delaware capes to Savannah, 370 ; on the lower Mississippi, 383 ; in eastern Florida, 520 ; in the southwest, 747. Among our troops now stationed in the tropics the rates are high, es- pecially so for those in Cuba. A comparison of the relative prevalence of malaria in the several tropical islands and within the United States, for the year 1899, is as follows: Malarial fever, intermittent . Malarial fever remittent Malarial fever pernicious . . . Malarial cachexia All malarial feotions . . . Cuba. 729.94 332.51 3.94 32.07 1,088.46 .25 1.75 .50 2.50 PORTO Rico. "K .be 345.85 100.62 1.07 11. 458.64 gj t, oj p. M Pacific Islands. 11^ ,ai-i a 388.82 216.45 1.15 17.92 624.37 0.20 .•46 .23 All Tropical Islands. 494.76 246.50 3.03 22.03 765.32 a-i a 0, fcH a) p. GO 0.21 .84 .30 1.35 United States. 237.84 38.37 .50 14.17 390.88 0.07 .13 .03 .31 For the world at large the relative distribution of malarial disease, as affected by climate, is well shown by the following figures for the British army, per thousand strength : station. United Kingdom Gibraltar Malta Canada Egypt and Cyprus. . Bermuda West Indies South Africa Mauritius Ceylon China Straits Settlements. . India West Africa Teak : Admissions. Deaths. 9.5 4. 152.1 .11 58.4 :::: 78.5 3.87 39.03 .12 380.3 1.22 71. 379.3 6.37 829.9 434. .76 2,027.8 13.89 Constantly sick. 0.87 .35 4.17 2.19 4.13 1.65 15.76 3.28 16.95 15.17 15.26 67.36 Decade 1888-1897. Admissions. 6.3 7.2 14.1 1.3 21.9 1.09 62.3 30.3 579,3 93. 489.6 95.4 356.9 1,815.8 Deaths. 0.01 .02 .08 '".02 "m .08 3.76 .87 2.86 .64 .71 53.63 Constantly sick. 0.38 .34 .66 .05 .85 .08 3.58 1.23 35.74 3.77 14.89 3.18 13.01 50.36 DISEASES OF THE SOLDIER. 711 At certain stations in India, malaria has been at times so prevalent that aU drills and parades have had to be discontinued. In former times, the death rate from this disease was often extraordinarily high ia the British army. Davy mentions an instance in Ceylon where every white soldier sent to a certain station contracted malarial fever ; and states that out of a total strength of 254 men there were 205 deaths from this affection. Next to climate, the influence of season appears to be of the most im- portance ; the rates for troops throughout the United States attaining the maximum in September and the minimum in February — as is well shown in the foUowing diagram. The relationship between malarial infection and marshy and swampy localities has long been recognized. Malaria, however, has been known M, .II- ■ iS- ■ »- ■!i- ■ u- ■ il- ■ zt- ■-% /S- .'A: ■n /I- 40 ■ S' il ♦• i i I J'eir. Jlflril. M, ay. W- w m. 'MM 5ii Ml J-iJy. I ^«^. Sept, I i; ■I! ■miM Vcl. W. ■■ im mm ■I ■ 'iim wiM ■■ m mm wm ■I 'm/t 'mm 'mm JK>- at ■'MM wm WM i/m. vm. wik i wm* > I w//iu w/in w/M w//, WM mil. ■mi. ■ wm ■ wi/m m v//M\ WM\ WM mn wmt wm. im m wi i %» i ? wii vMitt wm rmn mmi w/m m wt mm mi, ■ wm t um Year 1885. WHi^A Decade 1875-84. Fig. 347.— Diagram Illustrating the Distribution of Cases of Malarial Fever by Months, per Thousand strength. Occurring in the Unitea States Army. Also showing the constant reduction of malarial In- fections. to occur in localities not especially marshy and, on the other hand, to be absent from regions wet and swampy. Of this latter fact the city of Mexico, surrounded by lakes and marshes, furnishes a conspicuous exam- ple. It must be admitted, however, that malarial disease is much more frequent on marshy coasts and low, humid plains than on higher ground where drainage of the soil is more complete, and a certain amount of moist- ure in the soil is appearently essential to the development of the malarial virus. Marshes that are alternately flooded and partially drained of water offer conditions most favorable to the development of malaria. Under such conditions the profusion of rank vegetation, together with decaying organic matter, does much to favor it; though it may sometimes occur on barren, sandy soils with high ground-water, particularly if the soil be organically contaminated. The broad, alluvial deltas of great rivers and the valleys of smaller streams are, in warm climates, usually malarious. The break- ing or clearing of new lands, in malarious regions, usually results in an outbreak of the disease in the immediate vicinity ; but by prolonged culti- 712 THEOEY AND PEACTICE OF MILITARY HYGIENE. vation, malaria becomes less frequent and severe and may finally disappear. The geological character of a soil appears to play a somewhat important part in the production of the virus. An impervious surface-soil, which does not readily become saturated with moisture but favors the rapid shedding of storm water, is not regarded as favorable to the development of the disease. A permeable, shallow surface-soil lying over an impervious stratum may favor the development of malaria under conditions of very moderate rain- fall. In general, excessive or prolonged rain-fall favors the occurrence of the disease. At high altitudes, the disease disappears or becomes iafre- quent; in the tropics it is said that a height of as much as 2,000 feet is usually necessary to secure a fair immunity. In the Philippines, however, a very virulent type of malaria appears to prevail in the more mountainous districts. While troops may be attacked by malaria when on board ship, this is now rarely the case in practice. During the disastrous expedition of the' French in Madagascar, in 1895, it is said that not a single fatal case of malaria occurred on board the thirty vessels constantly maintained off the coast, and many striking instances to the same effect have been recorded. There is a general conviction that the malarious virus may be carried by winds. In malarious regions near the coast, the land breezes, especially if they traverse neighboring marshes, appear to favor the disease, while sea breezes do not. Many localities which might be otherwise highly suspi- cious, but which are continually wind-swept, are often free from the affec- tion. Undei* ordinary circumstances, the virus of malaria does not usually ascend very high above the level of the ground ; troops on the upper floors of barracks may largely escape the disease where those on the lower floors con- tract it. There is evidence, however, that the malarial infection may be car- ried to high altitudes by strong winds blowing up narrow unhealthful valleys. The recognition of the mosquito as an agent for the transmission of this disease has done much to explain the influence of air-currents in this re- spect ; and the same may also be said with regard to the supposedly bane- ful influence of night aij:, since the malarial mosquito is not active during daylight. Davy says of certain British troops in Ceylon that they were largely exempt from malarial fever as long as they were employed by day only ; so soon as they were employed more by night than by day, particu- larly in convoys and the relieving of posts, fever became very prevalent and destructive. Of one company seventy strong, which was forced to sleep out in the jungle for a single night, he states that every man contracted fever and many died. Lemiire gives an instance of a garrison of fifty French soldiers in Madagascar, of which at the end of two months six were dead, twelve had been invalided home and all the remainder presented malarial infections. At the same time, the sanitary condition was good among a body of marines at the same station and performing the same duty, but who returned to their ship at night to sleep. Experience shows that negroes, native to and living in a malarious country, possess an undoubted immimity to malarial fevers. This immu- nity, however, is lost to a considerable extent after long residence in a non- malarious climate, and does not exist to any very great extent among negroes native to regions where this disease does not commonly prevail. The differ- ence in respect to susceptibility between white strangers and native blacks DISEASES OF THE SOLDIER. 713 is, however, great. In the British expedition up the Niger, of 145 whites and 158 negroes, there were 130 cases of fever with 40 deaths among the whites, whUe there occurred among the negroes but ,11 mild cases, and these only in individuals who had passed several years in England. In West Africa, Great Britain has found it scarcely possible to retain white soldiers, and the garrisons are composed almost wholly of native negroes. For the decade 1888-97, the admission rates for malaria in West Africa was 1,815.8 for the whites, in spite of special precautions taken to prevent their infection, and but 990.9 among the negro troops. The death rate from this affection among the whites and negroes was 52.63 among the former, and but 5.75 among the latter. In our own service, the rates for malaria during time of peace are invariably higher among the whites than in the colored troops, although the difference is but slight as compared with the figures just given. During the war with Spain, the figm-es were reversed and the rates for colored troops were much higher than for the Hr If* /^-n^-A Zot^X^ I5t.l3. 5^6 3*, li-'-lS ion a iSa^g SiaSi iS^ S3. -/to — — /» — — /« — — ^i— ^~^H "^H . B ■ ^H" — 1— ^^1 ^H ^H ^B ■^ ~~^B 1 ^^ -/*— — H— ^H J ^_ - "~^ ^ ^ m ^ ^H -■- Tig. 348.— Admissions, per Thousand ol each class, for Malarial Fevers in the United States Army, Arranged According to Age, during the Seven Years 1890-96. white. This, however, is readily to be explained by the fact that the negro troops were nearly all engaged in the tropics, while many of the white soldiers, especially those in the artillery and cavalry, were not moved from the United States, or in some cases from their usual posts. Among our white soldiers, the native-born American appears to be slightly more susceptible to malarial infection than are the men of foreign birth ; thus, for the seven years 1890-96, the admissions for malaria, per thousand strength, amounted to 84.24 for American-bom whites; 81.94 for soldiers of Irish birth and 74.67 for those of German nativity. As is the case with nearly aU other diseases, age is a factor of great importance in predisposing to malarial infection, as is conclusively shown in the preceding diagram. During time of peace, for the seven years 1890-96, the admission rates for malarial disease, according to the branch of service, were proportioned as follows : Per - Per 1,000 of each class. 1,000 of each class. Ordnance 60.91 Medical department 55.31 Artillery 163.34 Engineers 130.66 Cavalry 110.79 Infantry 46.28 Many of the sea-coast fortifications garrisoned by artillery are notably 714 THEOEY AND PRACTICE OF MILITAEY HYGIENE. malarious, as is the station of the engineer troops. The greater prevalence of the disease in the cavalry as compared with infantry is to be explained by the greater proportion of field service performed by the former. Malarial fevers are much more common among soldiers than officers ; thus for the seven years 1890-96, the admissions ia our army, per thou- sand strength, were 81.74 for enlisted men and 40.20 for officers. Common experience shows that a considerable number of individuals, exposed to the malarial poison, escape infection. While this may be due to a racial insusceptibility, as already mentioned, the strongest predisposing element in the development of disease, to which malaria is no exception, is a lowering of vital resistance through unsanitary surroundings, bad food, exhaustion or exposure. Among these factors, physical exhaustion is not of the least importance — and in this connection Coustan calls attention to the fact that in the Madagascar expedition the proportion of deaths among the French officers was 1:16.6, while among the soldiers, who were ex- hausted by the carrying of heavy burdens and long marching, the proportion was 3:5. Under-fed or fasting troops are very susceptible to malarial influ- ences, and early morning drills before breakfast, or late guard duty, are especially favoring factors. Exposure to heat undoubtedly exerts a predis- posing influence to malarial infection, and the same is commonly believed to be the case with respect to alcoholic excesses. The acclimation of troops in a malarious country cannot be counted upon, military experience showing that the mortality from this disease increases with the length of the sojourn. One attack of malaria, unlike the eruptive fevers, predisposes to another; and it is a rule in the French service to select for expeditions in the tropics only such as have not previ- ously suffered from the disease. After residence in a malarious country, with or without symptoms de- noting an existing malarial infection, the disease often appears in a sharp or persistent form after removal to a region in which malaria does not origi- nate. This has commonly been observed in recruits sent from malarious stations to healthful districts in the west, and was particularly evident among oxa troops returned from Santiago. Prophylaxis. — This depends upon the application of both special and general measures of prevention, and of these the former are probably of the most importance. In the avoidance of malarial infection by inoculation, it is evident that troops should be shielded against the attacks of insects ; and further, that the insects should be destroyed. From the nature of military service, it is obvious that soldiers cannot at all times avoid being bitten by mosquitoes, especially in the field; much may, however, be accomplished to this end, and the less the number of bites the fewer are the chances of infection. In garrison, all doors and windows should be provided with screens and mosquito bars should be attached to aU beds. The nets should be square, should be hung inside a framework, and should be tucked carefuUy under the mattress aU around and stretched tightly better to allow the passage of air. The mesh may be fairly coarse, but must be free from rents. Care should be taken to destroy all mos- quitoes within the netting before going to sleep ; this being best accom- plished by having an assistant hold a light at one corner outside the net, toward which the insects fly and are readily despatched. In the field, in DISEASES OF THE SOLDIEE. 715 malarious districts, soldiers should be furnished with squares of mosquito net or head-nets for use at night. The weight need not amount to more than a couple of ounces, and such a protection would conduce much to comfort and health and amply repay its carriage. In camps, smudges made of green boughs lighted to windward, so that the smoke blows over the men, are often of great value; for this purpose the eucalyptus boughs are said to be especially valuable, the mosquito having an especial antip- athy to this tree. Any essential oil, as oil of pennyroyal, smeared in small quantity over the exposed surface or dropped on the pillow, may keep off these insects, but since these substances are volatile they require to be fre- quently renewed. In Italy, slices of onions are often used for the same purpose. Mosquitoes which have gained access to barracks or quarters may be destroyed mechanically, or by the fumes from burning pyrethrum powder, tobacco or even green wood. The vapor of turpentine also kills them ; and an excellent way of destroying those resting on the ceiling is to raise up under them cups Containing a little mineral oil, into which the stupefied insects fall on inhaling the vapor. Leggings are an excellent protection for the ankles against these insects, but gloves or head-nets can rarely be worn on the march. Since patients suffering from malaria are capable of directly infecting others through the agency of mosquitoes, they should always be treated under mosquito-netting; and this precaution sliould be continued for weeks after the actual fever has disappeared, cer- tainly so long as repeated microscopical examination shows the presence of the malarial organism in the blood. Where mosquitoes are present in barracks, suitable conditions for their development are usually found close by, as these insects rarely travel any great distance. In the case of Anopheles, these breeding-places are small stagnant pools. Where these cannot be filled up or drained, recourse should habitually be had to culicides for the destruction of the larvse and pupae. Por this purpose, the substance most available for military use is mineral oil ; this being sprinkled over the surface of the water, as with a broom, until a fine film is produced which destroys the larvse by cutting off the supply of air and choking their air-tubes. The adult insects, which subsequently alight on the surface to deposit their eggs, are also destroyed. This film must spread over the entire surface of the water and should have a permanency of at least three days, to kill the larvse as they are hatched from the eggs. The quantity of oH required naturally varies with the conditions met with ; but for small still pools probably one ounce of kerosene to each fifteen square feet of water-surface is sufficient. Sur- face vegetation, sometimes very abundant, may often obstruct the mechan- ical action of the oil, and in waters even very slightly running it must be frequently or continuously renewed. Petroleum, also, has the disadvan- tage of evaporating somewhat rapidly in warm weather. Strong infusions of tobacco are fatal to the larvse ; and they are destroyed by powdered chrysanthemum flowers, as now found in commercial insect powders, in the proportion of three parts in the mUlion. Eecently CeUi and Casagrandi have shown that gallol, in the proportion of seven parts to the million, is the most certain and effective agent in destroying the larvae, and possesses the additional advantage of great permanency. Whatever be the special method of destruction employed, the life history of the mosquito shows 716 THEORY AND PRACTICE OF MILITARY HYGIENE. that it should be repeated at intervals of about ten days. The introduction of small fish or minnows into Ashless breeding-places of the mosquito is of great importance, as these feed greedily upon the larvae and soon exterminate them. General measures of prophylaxis have been shown by experience to be of value in the prevention of malaria. It is not advisable to take an army into a malarious country during the fever season, and in localities where the ■disease prevails to great extent it is well to retire to high ground during the malarial period, as is done by the English in India and Jamaica and by the French in Guadeloupe. In locating a camp or post in a malarious dis- trict, special care should be taken in the selection of a salubrious site. In general, the appearance of the natives will give some knowledge as to the relative prevalence of this disease among them. The abandonment of highly malarious posts, in time of peace, is much to be desired and can usually be accomplished. The retention of unhealth- ful stations is at the expense of unnecessary suffering, and in the past many thousands of lives have been uselessly sacrificed to tenacity of position. With marching troops, zones of malarious country should be avoided or passed over as quickly as possible. The abolition of marshes by flooding or drainage, and the removal of adjacent shrubbery and rank vegetation are great prophylactic measures in reducing malaria in a garrison. Plants of rapid growth should be cultivated for the assistance which they give in removing moisture from the soil. For this purpose the eucalpytus, castor- oil plant and sunflower appear to be most satisfactory ; these not only dry- ing the ground but being shunned by mosquitoes. SubsoU drainage is often of great value, but this can rarely be thoroughly carried out in the military service. Barracks for hot, malarious climates should be raised on piers, be cemented underneath and be of two stories. AH water used for drinking purposes should be sterilized by heat. Food should be abundant and nutritious. Distributions of hot coffee for those on guard at night, or who are engaged in arduous labor, are often of value. The use of quinine as a prophylactic, where troops are temporarily exposed to marked malarial in- fluences, is of great importance, as has.,been repeatedly demonstrated. Not only are the cases of malarial infection greatly decreased in number by its use, but the character of the cases which occur is favorably modified. In general, a dose of five grains once daily wiU be sufficient, preferably taken shortly before any unusual exposure is anticipated. In a malarious country, the routine issue of q\iinine after anything lowering the resistive power, such as a forced march, wetting or lack of food, has much to commend it. In the Italian army, arsenious acid has been tried in the prevention of malaria, but with little satisfaction. Exposure, particularly to heat and night air, and over-exertion should be avoided. If disturbance of the soil be necessary, as little ground as possible should be disturbed at one time and the work should not be begun too early in the day. As few men as practicable should be employed in the work, and only such as have not had a previous malarial infection ; and the same applies to the composition of expeditionary forces into fever districts. DISEASES OF THE SOLDIER. 717 Measles. Occurrence. — Among troops, measles is of frequent occurrence. Un- der certain circumstances, when developed under conditions of want, hard- ship, exposure and bad sanitation — and especially when associated with a scorbutic taint — the disease may assume an extremely severe and fatal character. Formerly, the occurrence of the hemorrhagic form of measles was not infrequent among troops and was much dreaded. The exposure in the treatment of measles cases iu tent-hospitals, often unavoidable, does much to develop secondary bronchitis and pneumonia ; and to these latter causes is to be attributed, also, much of the gravity which the disease has assumed when prevailing among troops during the existence of hostili- ties. In garrison, the mortality from this disease is usually small; for the period of peace 1885-94, in our army, the death rate was but one one- hundred-and-tenth of the rate given by the Eegistrar-General for the total population of England and Wales, for the same cause, during the same period. From 1832 to 1859, however, according to Eosse, measles was the cause of 2.7 per cent, of deaths from aU causes occurring in the garri- son of Paris. During the CivU War there were, in the Union forces, 75,- 177 cases with 5,174 deaths; the admissions per thousand strength, during this period, amounting to 31.72 and the deaths to 2.02. Among the Con- federate troops. Eve states that measles prevailed to such an extent that whole companies, battalions and even regiments, under organization, had to be disbanded and the men sent home. During the siege of Metz, measles was extremely prevalent and fatal in the garrison. In our army, for the period 1868-98, there occurred a total of 3,733 cases with 15 deaths, giving an admission rate, per thousand strength, of 4.50 and a death rate of .017. The disease appears to be relatively more prevalent now than formerly among our troops, the rates being as follows : Period. Admissions per 1,000 strength. Deaths per 1,000 strength. 1868-84 1.88 4.85 13.73 004 1885-94 004 1895-98 09 The expansion of the army by a large number of susceptible recruits at the outbreak of the war with Spain, and their aggregation in large camps where the communication of the disease was favored, did much to raise the rates for admissions and mortality during the last period given above, the admissions for measles during the year 1898 being 25.09 per thou- sand strength, and the deaths amounting to .26 per thousand; while for the previous year of peace, 1897, the admission rate was only .82 per thousand, with no deaths. In the German army, the rates of admission for measles, per thousand strength, for varying periods, have been uniformly low, as follows : 1881-82 to 1885-86 1.4 1886-87 to 1890-91 1.5 1891-92 to 1895-96 0.83 Year 1896-97 1.1 718 THEORY AND PEACTICE OE MILITARY HYGIENE. In the French army, the rate of admission per thousand strength, for the five years 1890-94, was 9.71. Coustan believes that the system pre- vailing in the French army, of turning into a common magazine certain articles of the equipment worn annually for a few weeks during the field manoeuvers, greatly favors the dissemiaation of the infection of measles and hence partially explains the high rates to be observed in that army. In the Austrian service, for the year 1897, the admission rate was only 8 per thousand, but the proportionate mortality was high, .02. Colored troops appear to be less susceptible to measles than are whites, but certain mild cases are more liable to escape recognition iu the former class; the rates of admission in our army for measles, in 1898, were 25.91 per thousand whites and 14.42 for colored troops. During the CivU War, however, the rates were 30.41 for white, and 46.65 for colored troops- — ^this excess as regards the negroes being apparently due to lessened efforts for the control of the disease among them. The disease occurs far more fre- quently among recruits than old soldiers ; in the CivU War, the number of cases depending upon the proportion of susceptible individuals and occur- ring particularly in country-bred recruits. For the French army, Coustan gives the following figures with respect to length of service as influencing the occurrence of measles : Year. Less than one year service, admissions per 1,000 strength. More than one year service, admissions per 1,000 strengtti. 1891 23.63 9.62 11.98 14.80 12.69 1892 4.04 1893 6.08 1894 7.91 In our own service, measles prevails to by far the greatest extent at the recruiting depots; the recruits at Columbus Barracks, in 1892, furnishing more than half the cases occurring in the entire army. The disease, in this country, ordinarily occurs most frequently during cold weather, when ventilation is comparatively restricted and the oppor- tunity for infection is most favorable. During 1898, when the propor- tionate number of recruits was great, the rate of admissiqn was by far the highest during June and July — ^thus showing the greater importance of length of service as compared with season in influencing the prevalence of this disease. During the same year, the admission rate was 19.82 per thousand soldiers stationed within the United States, while there was a total rate of 48.25 for the troops serving in the West Indies and the islands of the Pacific. The case mortality of measles, as already noted, is capable of varying within very wide limits, ranging from as little as 1 or 2 per cent, in some outbreaks to 40 or 50 per cent, in others. "In Paris, during the siege (January, 1871), out of 215 of the Garde Mobile who took measles, 86, or 40 per cent., died; and the mortality reached very nearly the same figures among the French troops who returned to Paris after the Italian War, 40 out of 129 cases dying in one hospital whose sanitary condition was bad." As in typhus fever, the concentration of a large number of measles cases, with deficient ventilation, appears unfavorably to afi'ect the nrognosis and course of the disease. Infection and Dissemination. — From analogy, it may be assumed DISEASES OF THE SOLDIEE. 719 that the cause of measles is a specific micro-organism, but as yet its special nature has not been determined. The infection is presumably given off' by the breath and mucus -from the catarrhal surfaces, also by exfoliated epidermis. The poison is undoubtedly capable of being air-borne, and tends to cling to fomites and to remain in ill-ventilated spaces. The infectious agent is very tenacious of life ; and where it once fairly estab- lishes itself, as is apparently the case at present at Columbus Barracks, annual epidemics are the rule. There is no evidence that the disease is transmissible by water or food; infection probably always occurs tlirough inhalation. The disease is not infrequently introduced among troops in garrison by children. The incubation period varies from eight to twenty days, the usual limit being about eleven days. The infectivity begins with the earhest symptoms ; it is greatest while the catarrh and rash are pres- ent, and probably extends well into convalescence. As a general rule, in- fectiousness is over by the end of the fourth week, provided that cough and desquamation have ceased. One attack of measles usually confers immu- nity as regards future infections. Prophylaxis. — In view of the fact that measles is mild under favor- able conditions and may be very fatal when the patients are exposed to in- clemencies of weather, it was seriously advised, during the Civil War, to infect all susceptible recruits with this disease on their enlistment and thus insure their immunity before sending them to join their regiments hx the field. In civU life, vigorous efforts are rarely made to prevent the spread of measles, but in the military service the opposite should be the case ; bearing in mind that this disease is never devoid of danger and, particularly in the field, may at any time assume a grave character. Fur- ther, it causes the loss of a considerable amount of service by troops to which the state is entitled. The efforts toward prevention include the iso- lation of the sick and the disinfection of aU contaminated clothing, bedding and surroundings. The discharges should be disinfected, particularly those from the mouth and eyes. For receiving the latter, soft rags should be employed and these burned after use. As far as the patient is concerned, Cameron concludes that " so far as figures are of value, ample air-space, free draft, freedom from overcrowding and from effluvium nuisances conduce most to recovery." In the spring of 1898 the writer began some investigations with re- gard to the production of an artificial immunity against measles. The experiments were abruptly interrupted by field service, but appeared to be distinctly favorable so far as carried out. The method employed consisted in the subcutaneous injection of blood-serum obtained from convalescents from measles by means of cantharidal blisters. The injections were made in children living in an infected garrison, about 5 c.c. being administered in three doses at intervals of about forty-eight hours. None of the cases so inoculated contracted the disease, while a considerable proportion of the susceptible and uninoculated children became infected. Mumps. Mumps occurs very frequently among soldiers, especially young sol- diers, but its mortality is practically nil and it becomes of importance merely from the temporary disability for military service which it causes. 720 THEOEY AND PRACTICE OF MILITARY HYGIENE. ' In a total of 3,122 cases of mumps occurring in the United States army for the thirty-one years 1868-98, inclusive, there was not a single death which could be attributed to this affection. The admission rate for mumps during the period 1868-84 was 2.99 per thousand strength; for 1885-94 it was 5.08, and for 1895-98 it was 4.05. The rate of admissions for the entire period, 1868-98 inclusive, was 3.76 per thousand. In the military service, mumps usually prevails in well-defined epi- demics, and a large proportion of the cases occur in recruits. The aggrega- tion of such young men at certain stations, for purposes of instruction, is very favorable to the appearance of this disease; and in 1894, out of 337 cases of mumps occurring in the army, there were 119 cases at the two recruiting depots of Columbus Barracks and Jefferson Barracks, while in the previous year, out of a total of 149 cases, 43 cases occurred at the first named station. Orchitis and atrophy of the testicle are very common among soldiers affected with mumps, being present in about one-third of the cases. Coustan states that in an epidemic among French soldiers, in 1891, every man attacked by mumps developed orchitis; while Laveran foimd it 211 times in 699 cases. The infectious agent is supposed to be given off by the breath and the secretions of the mouth, but as yet no specific organism has been isolated. It is not conspicuously disseminated by means of fb- mites ; in garrison, it frequently appears to be introduced from outside by children. The period of incubation is reckoned as from fourteen to twenty- five days, and the case is regarded as infectious while there is any in- flammation or tenderness of the salivary glands. Sanitary precautions con- sist in the isolation of the patient and the disinfection of his clothing and equipment. Beyond the cleansing and disinfection of the cuspidors in the squad room, no further preventive measures, in view of the comparative triviality of the affection, will usually be necessary. Among soldiers, outbreaks of mumps not infrequently occur in close association with measles, but this apparent relationship is probably to be regarded as acci- dental. The disease is most common during the colder weather. Plague. Occurrence. — With the recent appearance of plague in the Philippine and Hawaiian Islands, this disease at once assumes a practical importance in relation to our military service. Plague has not, in recent years, figured to any extent among the diseases affecting troops of any nationality; but numerous military epidemics have been reported in the past. The de- struction of the Assyrian army, recorded in II Kings, was probably due to plague; and the disease described by Thucydides as affecting the 200,000 men immured in Athens, in the Peloponnesian War, presented the symp- toms of the catarrhal form of this disease. Plague ravaged the armies of the Crusaders, and it is said that in the first crusade no less than 50,000 men perished from this disease before Antioch. The soldiers of Cromwell died of plague as well as typhus ; and it prevailed among both French and English during the first occupation of Egj-pt. In 18 16 it was imported mto Arabia by the Egyptian army, and has since prevailed there eiidemicaUy. A military epidemic of this disease is said to have occurred as late as 1828, in the Eussian expedition against Turkey. Plague prevails endemically in DISEASES OF THE SOLDIEE. 721 China, western Asia, northern Africa, and perhaps India ; from which points it has from time to time extended. It has recently been carried to Uru- guay, Brazil, Mexico, and, in this country, CaUfomia. It has also been lately transported to New Zealand, Madagascar, South Africa, New Guinea and a number of islands in the Pacific, among which are our own possessions. Cause. — Plague is caused by a specific bacillus; foimd in large num- bers in the suppurating glands and to a less extent in the blood. Under these conditions it appears as a small oval rod, somewhat smaller than the typhoid bacillus. The ends are rounded, and in stained preparations a portion is sometimes left uncolored in the middle of the bacillus. Stain- ing is readily accomplished by any of the ordinary aniline dyes. The bacOlus is decolorized by Gram's method of staining. In the tissues, the bacUli are found scattered among the cells, for the most part lying singly, though pairs are also seen; but in cultures, especially in fluids, they have a tendency to grow in chains. They are not spore-forming, are actively motile and have been shown to possess flagella, which, however, stain with difficulty. The ba- cillus is readily cultivated on ordinary media at body temperature. It grows on solidified blood serum, without causing liquefaction, as a yeUow- ish-gray deposit; the colonies appearing as cir- cular discs having a smooth shining surface. When cultures on agar, with a dry surface and slightly alkaline reaction, are incubated at body temperature, involution forms rapidly appear. These are seen on the third day and present ^'^ag^Vpi^il-omBub^MAf- the most varied forms ; Haffkine states that some ter Abbott.) reach a size many times that of the healthy ba- cillus. In bouillon, the growth usually forms a slightly granular or pow- dery deposit at the bottom and sides of the flask. If the bouillon be kept absolutely at rest, flakes form at the surface, and growth extends downward from these, forming the so-called "stalactites." These columns of growth are easily broken up when the flask is moved, and fall to the bottom as a powdery deposit. Haffkine regards this feature, together with the involu- tion forms on dry agar, as of great importance in the recognition of the or- ganism. In its powers of resistance, the plague bacillus corresponds to the other spore-free bacilli and is readily killed by heat. It resists dry- ing for four days at the longest, and exposure to direct sunlight for three or four hours destroys it. When cultivated outside the body, the bacillus rapidly loses its yirulence. Predisposing Causes. — The mortality from bubonic plague varies with different epidemics. Pace exerts a marked influence both on the occurrence of the disease and the mortality. Of late years, whites in the Orient have rarely contracted the disease ; and, when so afifected, the mcff- tality is low. In the epidemic at Hong-Kong, in 1894, Lawson states that the percentage mortality of those attacked was as follows : Europeans, 18.2; Japanese, 60.0; Malays, 100.0; Chinese, 93.4. The disease is pre- eminently favored by want, privation and lack of proper sanitation. Haff- kine places the average period of incubation of the disease at about six days, but this is exceeded in many instances. 46 722 THEORY AND PRACTICE OE MILITARY HYGIENE. Propagation and Dissemination. — Plague has developed so uniformly in unclean places that filth is regarded as an essential factor in its propa- gation and spread. Almost without exception, plague-centers have been characterized by a soil polluted by decomposing animal material and by the overcrowding of a dirty and insufficiently nourished population. Plague bacilli have been isolated from the dust of infected houses, and the pest is generally regarded as a ground rather than a water disease. In the epi- demic in Hong-Kong, in 1894, Lawson was impressed with the part which dust and dirt played in the transmission of the infection. When the microbe is removed from a soil saturated with organic filth, it appears to lose much of its virulence. The baciUus has been shown to survive for two weeks in water,- and hence the supply used for drinking and purposes of cleanliness should be pure. While the disease appears at times to be transmissible by air, this is possible only within a small radius ; there is con- siderable evidence to show that it may be transmitted by means of food. The disease may be spread by means of clothing and other articles which have been used by plague patients ; but is most often disseminated by human in- tercourse. Aoyama believes that the specific bacillus gains entrance to the body largely through skin wounds, and much less frequently than has been supposed by way of the respiratory and alimentary tracts. The fact that there may be no local manifestations at the lesion of entrance is important. A large number of animals, particularly rats, mice and small rodents, are susceptible to the disease. Eats die in great numbers in pest-smitten districts, sometimes before the affection appears in human beings. There can be little doubt that these animals play a most important part in dis- tributing the disease over wide areas from a focus of infection, when it has once broken out. This has been abundantly proved in the case of Bom- bay, where observation has shown that the emigration of plague-infected rats to districts comparatively free from the disease has been attended by an extensive outbreak in the latter places. In addition to the pus of sup- purating buboes and the blood, the baciHi have also been found in the spu- tum, urine and faeces of both men and animals. Further, it has been shown that the flea is frequently an agent by which inoculation is made from affected to sound animals. Pest bacilli have been found in the stom- ach contents of these insects, and fleas taken from plague-afflicted rats have been made the means of communicating the disease to healthy animals. Nuttall, Yersin and Ogata have found pest bacilli in large numbers in the bodies of flies in an infected locality. Even after forty-eight hours' reten- tion in a clean receptacle without infected food, infected flies were found to be fuU of virulent bacilli. The experiments of Nuttall and Ogata are to the effect that ants and mosquitoes may be the carriers of this disease ; the latter producing infection by dnect inoculation. Bedbugs, however, appear to digest and destroy the baciUi. From the facts stated with regard to the powers of comparatively rapid multiplication of the plague bacillus, its wide dissemination by the excreta and by animals and insects, it may be understood how extensively soil and habitation may become infected and how correspondingly difficult it may be to arrest the ravages of the disease. The important part played by the infection of a locality is strik- ingly shown by the rapid fall in the number of cases when an infected site is abandoned and the inhabitants are placed in tents. DISEASES OF THE SOLDIER. 723 Prophylaxis. — The most important safeguards against the threatened development of plague are cleanliness of person and surroundings, good drainage, free ventilation, a proper standard of nutrition and a war of ex- termination against rats and mice. In addition, the prophylactic use of Haffkine's anti-plague serum is of great importance. When the disease makes its appearance, the sick should be at once isolated in tent hospitals, and all who have come in close contact with them, or have been exposed to the same conditions, should be quarantined and kept under observation for ten days. The belongings and surroundings of the patient should be carefully disinfected. The sputum, uriue, fseces and dressings from sup- purating buboes should be burned. Only healthy persons, free from abra- sions, sores or ulcers, should be allowed near the sick ; and such should be required to maintain scrupulous personal cleanliness and take a disin- fectant bath at least once daily. Troops should receive abundant food and pure water ; and the necessity for personal cleanliness and the frequent change of clothing impressed upon them. The use of well-fitting shoes, together with great care of the feet, is necessary ; since there is considera- ble evidence to show that inoculation usually takes place in the lower ex- tremities. Soldiers should avoid infected districts, except under competent authority. If proper care be taken, the liability of white troops to contract this disease appears to be slight. At Hong-Kong, in 1894, of 300 British soldiers who volunteered to assist in the sanitary policing of infected houses, but 10 contracted the disease; in Poena, in 1897, of over 900 white soldiers so engaged, not one became infected. In the latter instance the precautions taken included merely a hearty meat meal before begin- ning ,the work of the day; the retention in camp of all cases of slight ailment or those presenting cuts or abrasions; immediate disinfection by antiseptic solutions of cuts or bruises incurred during the work, and the thorough sunning of the clothing worn, for the rest of the day, after return to camp. Every effort should be made for the destruction of rats and mice, which are very susceptible to invasion by the pest bacUlus and which obviously can escape the best sanitary cordon and neutralize the most thorough dis- infection. The wholesale poisoning of these rodents is not without its dangers and, lil^e the use of traps and ferrets, is only partially effective. Eecently Danyoz has shown the possibility of destroying them in large numbers by means of bread or grain soaked in cultures of the bacillus ty- phi murium. Not only do the animals readily eat the infected foods, but the disease thus communicated is further propagated by the affected animal to others. The bacillus employed is pathogenic only for the rodents. Such individuals as recover from the disease should be kept in quaran- tine for at least a month. Kitasato has found the bacillus of plague in the blood as long as three weeks after the beginning of convalescence. Preventive Inoculation. — The system of preventive inoculation against plague, as devised by Haffkine, has been carried out on an exten- sive scale in India during the past six years. The method has been sys- tematically tested by inoculating a certain proportion of the inhabitants of districts exposed to infection, leaving others uninoculated, and then observ- ing the proportion of cases of the disease, and of fatal cases, among the 724 THEOEY AND PRACTICE OF MILITARY HYGIENE, two classes. The results have been distinctly favorable to the use of the preventive fluid. At Poena, inoculation was practised with anti-plague serum on the native followers of the artillery troops stationed at that point. While everythiag was done outside of inoculation to prevent the spread of the disease, ia 859 uninoculated there were 143 cases with 98 deaths, and iu 671 inoculated there were 32 cases with 17 deaths. Had the inoculated, living under the same roof, belonging to the same families and sharing the same food and drink, been equally affected, the proportionate number of deaths among them would have been 77. The inoculation therefore re- duced the death rate 77.9 per cent. In 1898, at Hubli, 3,815 persons not inoculated with anti-plague serum had 446 attacks, while 26,428 persons twice inoculated had only 31 attacks. If the latter had suffered propor- tionally as much as the non-inoculated they should have had 3,089 at- tacks — and such examples might be largely multiplied. In a statement, published in June, 1899, Haffkine states that in the large number of inoculations made with anti-plague serum, the difference in number of attacks occurring in inoculated and uninoculated was over 80 per cent.„ often approaching 90 per cent. The lowest in his experience was 77.9. The case mortality also was only half as great as among the uninoculated. To make the prophylactic material, Haffkine cultivates in bouillon luxuriant growths of plague bacilli, usually obtained from the livers of plague patients, by adding to the nutrient mediimi an abundance of fat. exposed to free aeration. For this purpose he employs the clarified butter, or "ghee," commonly used in India. This floats on the surface of the bouillont and after inoculation of the latter the growths extend downward in a stalactite formation, leaving the liquid limpid. When the fluid is. filled with an abundant growth, the flask is shaken and the stalactites are broken and fall to the bottom ; fresh growth then occurring from above down- ward. In this manner, half a dozen crops are obtained in the course of a month, flUing the flask, when shaken, with an opaque milky emulsion. The micro-organisms are then destroyed by a temperatm-e of 70° C, main- tained for one hour, and the final result is an abundant deposit with a clear- supernatant fluid. Injected subcutaneously into animals, the sediment pro- duces a local inflammation and a nodule at the seat of inoculation, but is- accompanied with little fever or general disturbance. The injection of the fluid, on the contrary, causes a considerable rise of temperature with malaise, but no local effects. A mixture of the clear fluid and deposit is. used in inoculation against plague, about 5 c.c, usually divided into three doses which are administered about ten days apart, being the amount em- ployed for adult males. The injection is followed by an unpleasant reac- tion with pyrexia, 101° to 103° F., and general symptoms resembling a mild attack of plague ; in some cases even producing enlargement of the glands and lasting several days. The prophylactic serum begins to act in twelve to fourteen hours, thus arresting or mitigating the disease in indi- viduals infected several days before. The effect of an inoculation of plague serum appears to be of protective value over a single epidemic, but expe- rience has not as yet shown how long the immunity persists. Yersin, Calmette and Borrel succeeded in producing a certain amount of immunity against plague, in rabbits, by injection of cultures of this DISEASES OF THE SOLDIER. 725 bacillus killed by heat at 58° C. They further found that the serum of such animals had certain protective powers when tested on mice. Later, Yersin and Symmers endeavored to produce a prophylactic serum from horses, by the injection of dead and living cultures of the bacillus of plague into these animals. Yersin' s serum promised fairly well at the outset; but Symmers, working along the same lines, concludes that "the strength of the sera secured is not sufficiently great to warrant any hope of their be- ing of therapeutic use in an actual epidemic of plague." Pneumonia. Occurrence. — Acute croupous pneumonia is a disease which, as might be expected, considering the conditions of military life, though not one of the most common to which the soldier is exposed on service, is yet not of infrequent occurrence nor unproductive of considerable mortality. Though ordinarily the disease occurs only sporadically, yet at times it appears to take on a distinctly contagious character, and well-defined epidemics of pneumonia among soldiers, either in garrison or in the field, are by no means infrequent. Under such conditions, it is reasonable to assume the existence of some common depressing influence, by which a number of individuals are predisposed to an infection to which, under ordinary cir- cumstances, they would be largely insusceptible. In considering the oc- currence of this disease in the military service, it should not he forgotten that pneumonia may either occur primarily or be consequent to some other disease, especially influenza and measles ; and it is particularly during epi- demics of the latter affections that the rates for pneumonia attain their maximum. While the disease not infrequently occurs among troops in garrison, it is considerably favored by the exposure incident to field service. The rates in our army for pneumonia, since the Civil War, have stead- ily decreased as a result of the greater care given to the comfort and welfare of the soldier, as shown by the following figures : Period. Admissions per 1,000 strength. Deaths per 1,000 strength. 1861-1866 (Civil War) 1868-84 1885-94 1895-98 Year 1898 (War with Spain). Year 1897 32.45 6.55 4.38 3.66 4.84 2.96 7.79 1.01 .76 .51 .83 .31 The case mortality of the disease has also greatly diminished, but this is probably due to a more rational line of treatment than to any decrease in the virulence of the infection. As compared with the rates for foreign services, those for our army are extremely low — ^thus in the German army the admissions and deaths from pneumonia have been as follows : Period. Admissions per 1,000 strength. Deaths per 1,000 strength. 1881-83 to 1885-86 1886-87 to 1890-91 1891-93 to 1895-96 Year 1896-97 11.0 10.5 9.3 6.7 0.19 .43 .36 .35 726 THEOEY AND PRACTICE OF MILITAEY HYGIENE. It is seen that in the German army the death rate has increased while the proportion of cases has diminished, a fact which can be explained only on the supposition of an increase in the gravity of the affection. In the Eussian army the following are the more recent rates : Tear. Admissions per 1,000 strength. Deaths per 1,000 strengtii. 1890 10.4 10.2 8.7 10.7 7.7 ■ 8.3 7.7 6.4 0.99 1891 .90 1892 .81 1893 .87 1894 ... .62 1895....... .66 1896 .62 1897 . .49 In the Austrian army, for the year 1897, the admissions for pneumonia, per thousand strength, amounted to 6.1, while the death rate was .49. Cause, — The cause of pneumonia is the specific micrococcus discov- ered by Sternberg, of the United States army. It usually occurs in pairs of rather small oval, conical or lancet-shaped organisms, the broader ends being in apposition. The organism varies somewhat in size. In some cases atypical or involution forms are seen, especially if the culture be more than twenty-four hours old. No capsules are usually observed in cul- tures, with ordinary methods of stain- ing. It is not motile, has low powers of resistance and is readily destroyed by either thermal or chemical methods of disinfection. The micro-organism is cultivated with difficulty, and at times dies out after several generations. On blood-serum it occurs as minute, colorless, transparent colonies, resem- bling very small drops of dew. On glycerin-agar there is a feeble growth of minute grayish colonies. The most favorable temperature for its develop- ment is about 37° C. It does not grow at temperatures below 25° C. nor above 42° C. When injected into certain animals, especially mice and rabbits, the latter die rapidly from septicsemic infection. Great variation in the vii'ulence of the organism is observed. Dissemination and Infection. — The specific micrococcus of pneu- monia is found in the sputum of practically all persons suffering from this disease. It has also been found in acute peri- and endocarditis, acute pleuritis and empyema, acute meningitis and otitis media. After death it may be found, in varying numbers, scattered throughout the body. It has been found to be usually present in the mouth cavities of healthy individ- uals, and by some has been thought to be present in the mouth of every one at some time or other. While the micro-organism usually loses much or all of its virulence by artificial cultivation, its original qualities are re- FIG. 350.— Micrococci ol Pneumonia In Sputum. (After Ahhott.) DISEASES OP THE SOLDIER, 727 tained in sputum, blood and other pathological exudates for considerable periods, according to Abbott for as long as fifty-five days, even in the dried condition. It is not unlikely, therefore, that dried pneumonic sputum, when ground into dust and inhaled, may induce the occurrence of the disease in susceptible individuals. This condition of susceptibility is, however, essential. " There must be some predisposing cause, for the micrococcus is widely disseminated and is often present in the mouths of healthy persons without producing any ill effect. Under ordinary circumstances the protec- tive mechanism of the body prevents invasion." Since the micro-organism L., Jan.. T.Jr ■KKf. V- JHiy. t^l^ne^. J.ly 4h, S,;.. &^ ■Ifaf. Mec. -^- •■ji- ■es. ~ - H 1 ^^H ^H~ ^^1 1 - ^m 1 ^H 1 ^ 1 % i §1 s ^ Fig. 351.— Distribution of Cases of Pneumonia In the TJnlted States Army, per Thousand Strengtii, Occur- ring Monthly during the Decade 18T5-84. of pneumonia is so frequently present in the mouth, it is probable that the sporadic cases of the primitive disease so commonly seen are the result of auto-infection depending upon a lowered vital resistance. As the lungs are the seat of attack, it would appear that the infective organism gains entrance by the air passages ; though there is some evidence that it may be brought to the lungs from distant parts by the vascular or lymphatic circulation. Predisposing Causes. — Among the predisposing causes of pneumonia those of latitude and season are of much importance, the disease being most common in cold climates and during late winter and early spring. The distribution of the disease by months is shown in the above diagram ; while the influence of climate upon its occurrence is apparent in the fact that the admission rate per thousand strength, for the year 1899, was 9.50 for troops stationed in the United States and 3.58 for those serving in the tropical islands. The disease, once contracted in the tropics, appears to be relatively more fatal than in the temperate zone ; the death rates for the same year being .63 per thousand for the tropical islands and 1.40 for troops at home stations. The negro race appears to be especially susceptible to pneumonia ; the rates per thousand for our own service, for the decade 1879-88, being 7.52 for admissions and 1.79 for deaths among the colored troops, and but 4.46 and .76 respectively for the white troops. Among the whites, figures for the seven years 1890-96 showed the American-bom to be about twenty per cent, more liable to contract the disease than soldiers born in Ireland, Germany or England. Age appears to be a factor of no small importance — soldiers under 25 years of age and over 60 years being more than twice as liable to contract the disease as those between 25 and 35 years of age. Among the several arms of the service, the admission rates per thousand 728 THEORY AND PRACTICE OF MILITARY HYGIENE. strength, for the period 1890-96, were 4.12 for cavaby, 3.46 for infantry and 2.95 for artillery. Pneumonia is especially apt to develop after exposure to sudden and extreme variations in temperature. Troops returning from service in the tropics, and especially such as are insufficiently clothed for the colder cli- mate, are particularly liable to this disease. Wetting appears not infre- quently to precipitate an attack, as do exhaustion and alcoholism. The disease often occurs in soldiers who, after having been exhausted by fa- tiguing exercise, expose themselves while sweaty to chilling drafts. In- sufficient heating of barracks has been thought, with some reason, to favor pneumonia. Eepeated outbreaks sometimes occur in the same buildings, especially casemates and old log structures. It is a matter of common knowledge that outbreaks of this disease among soldiers often occur at the same time as epidemics of pneumonia or influenza in cavalry horses, with whom the men come in constant contact. Prophylaxis. — From what has been said, it is evident that measures having reference to the prevention of pneumonia among troops are particu- larly those which look to the maintenance of a high physical tone. Good and sufficient food, suitable clothing and shelter, rational exercise in the open air, cleanliness of person and temperate habits are all important. Chilling after drUls and exercise should be avoided. When pneumonia assumes an epidemic or infectious type, the patient should be isolated. All the precautions required in the case of tuberculo- sis should be taken in this disease also. Attendants in charge of pneu- monia cases should be well nourished, have sufficient rest and not be in too close relation with the sick; bearing in mind that by being over- worked and in constant association with the patient they offer the condi- tions most favorable to their own infection. Scarlet Fever. From its comparative rarity, this affection can scarcely be regarded for our own army as a soldier's disease, but is here included since it is less uncommon in the military forces of other nations. During the period 1868-98, there were reported only 160 cases of scarlet fever in a total nu- merical strength for this period of 859,908 men. In these 160 cases there were altogether but 6 deaths. The disease occurs in garrison rather than in camp, there being but 12 cases during the year of war with Spain. Of these 12 cases, however, 3 died, while of 148 cases occurring during the previous thirty years of peace but 3 succumbed — thus showing the unfavor- able influence of the exposure unavoidably incident to treatment in field hospitals. The admission rate, per thousand strength, was .19 for the pe- riod 1868-84; .18 for the period 1885-94 and .21 for the period 1895-98. In the Austrian army, for 1897, the admission rate is given as .30 per thousand strength, and the death rate as .01. In the German army, scarlet fever has occurred as follows : Period. •f^S'^'°°L^ per 1,000 strength. 1881-83 to 1885-86 1.2 1886-87 to 1890-91 95 1891-92 to 1895-96 92 Year 1896-97 66 DISEASES OF THE SOLDIER. 729 Epidemics of scarlet fever have frequently prevailed among children living at our army posts, without the troops being affected. The disease usually occurs in late winter or early spring. Its etiological factor is un- known, though Klein has isolated a streptococcus from cases of this affec- tion which he regards as the causative agent. The contagion of scarlet fever is probably not developed until the eruption appears, and is especially to be dreaded during desquamation; when the poison is spread by the fine particles of epidermis which are disseminated from the person. The mor- bific agent is very tenacious of life, and may cling to rooms, clothing and other articles for long periods, retaining its power to reproduce the disease under favorable conditions. The infection also appears to be given off by the breath and in the secretions from the nose, mouth, ears and kidneys. The disease does not seem to be spread by water, although infected milk appears to have caused outbreaks. Infection is almost always contracted by inhalation. The incubation period is one to six days ; the quarantine required is usually from seven to nine weeks, or until desquamation is per- fected. Preventive measures include isolation of the sick as a matter of the first importance. The apparel, equipments and former surroundings of the patient should be carefully disinfected. AU discharges should be dis- infected before removal from the room, and the arrest of contagious mate- rial from the skin secured by the application of some antiseptic ointment. The convalescent should not associate with others until all desquamation has ceased, the process being aided by repeated bathing in warm soap- suds. Careful shampooing of the head is essential in securing final disin- fection of the person. Smallpox. Occurrence. — Until well within the past fifty years, this disease has prevailed generally among armies ; being regarded as one of the most fre- quent and at the same time most fatal affections to which troops were com- monly exposed. Its prevention among soldiers by means of vaccination was not attempted until 1831, when this operation was introduced in the army of Wurtemberg. Some years later, it was taken up in other armies and practised with more or less thoroughness. During the Eevolutionary War, the failure of our invading expedition to Canada was largely due to a scourge of smallpox among the Conti- nental forces. It W£L3 present among our troops during the war with Mexico; and during the Civil War there were 18,962 cases with 7,058 deaths from this cause. In the Confederate army of northern Virginia, from October, 1862, to January, 1864, there were 2,513 cases and 1,020 deaths. During the Franco-Prussian War the German troops, who had been carefully vaccinated, had only 278 fatal cases of smallpox in a total strength of 913,967 men; while among the poorly protected French troops, the deaths from this cause were said to have amounted to 23,400 — and Coustan states that during the siege of Paris the mortality from smallpox among the besieged forces was no less than 6.76 per cent. In the miLL- tary hospitals, during that war, the G-erman wounded escaped variola where the French wounded prisoners were generally attacked. The lesson was not lost on the French authorities, and a vigorous system of vaccination was 730 THEOEY AND PKACTICE OF MILITAEY HYGIENE. later instituted — so that 92 deaths from smallpox in 1877 were progressively reduced to 4 in 1890 and 3 in 1892. In the German army, excluding the Saxons and Bavarians, for the years 1873-74 to 1896-97, inclusive, there were but 17 cases of variola in a constant strength of over half a mUlion men, and of these 17 cases but 2 died. In the Italian army of 204,312 men, for the year 1897, there were but 2 cases of variola; in the Eussian army, for the same year, the admission rate per thousand amounted to .4 for this disease. In the British army, for the years 1888-98 inclusive, there were no cases of smallpox among such troops as were stationed in the temperate zone. In the tropics, however, the disease prevailed to no small extent; the admissions, per thousand strength, beiag 1.1 for China, .8 for India and 1.7 for Egypt and Cyprus. This difference was undoubtedly due to the general dissemination of the disease among an unprotected native population. In our own army, for the thirteen years 1885-97, there oc- curred but six cases of smallpox, and in these instances the fact of previa ous vaccination could not be determined. In the year 1898, however, our troops on foreign service were brought in contact with an un vaccinated native class, and furthermore consisted largely of recruits hastily enrolled in an expanded and provisional army during the war with Spain. These men, examined for enlistment largely by oivUian. physicians, were un- doubtedly less thoroughly vaccinated and protected against the disease. That this, indeed, was actually the case, is shown by the fact that of the regulars and volunteers serving in the Philippines during 1899, the ad- mission rate for smallpox was 4.80 per thousand strength among the former, and 9.60 among the latter troops. The relative death rates from this disease showed an even greater difference than the admissions ; the regulars having a death rate of 1 per thousand strength, while among the volunteers this rate was 3.36 per thousand. For the calendar year 1898, the admission rate, for the entire army, was .40 per thousand; from the troops in Porto Eioo the admissions were 1.04 and the deaths .52 per thousand, while in the Pacific islands the admissions were 5.51 and the deaths 2.07. For the entire military force, regulars and volunteers. May, 1898, to June, 1899, inclusive, the death rate from smallpox was .57 per thousand. Infection and Dissemination. — The cause of smallpox is as yet un- discovered. In the great majority of cases the disease appears to be directly transmitted from the sick to the well through the medium of the atmo- sphere, and this power of aerial convection is one of the most striking characteristics of smallpox. Persons unprotected by vaccination apparently contract the disease by simply breathing the air of the space in which a smallpox patient is confined. There is no evidence for its transmission by food or drink ; but persons or things which may have been in contact with the patient are capable of conveying the infection. Power states that the infectious agent may be carried by the air, particularly when a large number of smallpox cases were aggregated and the atmosphere was moist, for as much as a mile — and tliis is a matter for consideration in the establishment of isolation hospitals. The incubation period of the dis- ease is about twelve days, and its period of infectiveness is at least six weeks in severe cases. The period of highest infectivity is believed to be during the stage of desquamation, when the morbific agent, whatever DISEASES OF THE SOLDIEE. 731 J. £. be its nature, is dispersed with the fine particles of scab and epidermis shed by the patient. The disease appears to be contagious at an early stage ; after exposure to an infection the susceptible individual should be quarantined for a fortnight. A certain proportion of individuals, accord- ing to Hotter and Firth about five per cent. , appear to be naturally im- mune to the disease. Soil and climate appear to have no influence on the occurrence of smallpox. Season appears to affect its prevalence to some extent, and in temperate climates the mortality curve is above the mean in the late winter and early spring. In the tropics, the disease is said to prevail chiefly during the hot season, the rains checking it to a great ex- tent. The negro and colored races are especially susceptible to the smallpox and also suffer a heavy case mortality where vaccina- tion has been imperfectly performed. During the Civil War, the admissions among the white troops for variola and varioloid amounted to 5.5 per thou- sand strength, while the admissions from colored troops for the same cause amounted to 36.6 and the deaths to 12.2. Prophylaxis . — There is no evidence that the smallpox poison multiplies outside the human body; hence for the prevention and eradication of this dis- ease, systematic vaccination is the measure of by far the greatest importance. When arm-to-arm vaccination was practised in armies, great difficulty was found in obtaining the necessary amount of virus, and it was also impossi- ble to eliminate entirely the danger of transmitting certain constitutional diseases. Animal vaccine disposes of this danger, and places at the disposal of the military sanitarian as large quantities of prophylactic material as may be desired. With improved virus and better technical methods of inocu- lation, the proportion of successful vaccinations has steadily increased. In the Italian army, of 3,095,571 vaccinations and re-vaccinations made during the period 1867 to 1897 inclusive, Livi states that the rate of success in- creased from 260 per thousand in 1867 to 698 per thousand in 1897. In the last named year, in the Belgian army, the number of successful primary vaccinations was 69.91 per cent. ; of those previously vaccinated, 43.21 per cent. ; of those said to have had smallpox, 20.50 per cent. In our own service. Mortality. Sickness. Fig. 352.— Vaccination and Smallpox in the Italian Army, A^ Never had variola or been vaccinated In childhood, and not yet vaccinated in the army ; B, either had variola or been vaccinated in childhood, and not yet vaccinated in the army ; C, never had variola nor vaccinated in childhood, and vaccinated In the army without success ; £), never had variola nor vaccinated in child- hood, and vaccinated in the army successfully ; B, had variola or was vaccinated In childhood, and vaccinated In the army without success ; F^ had variola or was vaccinated in childhood, and vaccinated in the army successfully. (After Livi.) 732 THEORY AND PRACTICE OF MILITARY HYGIENE. army regulations require that as soon as a recruit joins any rendezvous, regiment or post, he shall be examined by a medical officer to ascertain whether vaccination is required. In such cases as present no evidence of successful vaccination within a reasonable period, the operation is to be performed immediately. The date and result of last vaccination are to be noted in the company descriptive and deposit book, and also on the de- scriptive list of the man in case of transfer. This system is not sufficiently comprehensive and leaves too much to the discretion of the medical officer. It should be required that all young recruits be vaccinated immediately on enlistment, and that they be examined after ten days and re-vaccinated if the first operation has not been successful. In such as still prove refrac- tory the operation should be repeated at the end of three months. In time of epidemic, the thorough vaccination of the whole command should be practiced. For old soldiers, after being vaccinated on re-enlistment, no repetition of the vaccination, if unsuccessful, will ordinarily be necessary. The practice of simultaneously making several points of inoculation, as is done in European armies, has much to commend it as reducing liability to failure ; and, in general, the total area of the cicatrices should not be less than half a square inch. The incubation period of vaccinia being shorter than that of smallpox, it is possible to modify or even entirely prevent an attack of the latter by vaccination performed some days after infection. This is especially the case with re- vaccination, the incubation period of which is often shorter than primary vaccination. The operation, if successfully performed within three days after exposure to smallpox, will prevent the appearance of the symptoms, and in all likelihood the attack will be arrested or modified if vaccination be performed as late as the fifth day. The few attacks that occur between six and nine days after successful vaccination are mild, and practically none commence later. With regard to what may be accom- plished in controlling epidemics of smallpox, the recent work of army medi- cal officers in Cuba and Porto Eico is a conspicuous example ; in the latter island nearly a million people being vaccinated and the disease practically eradicated in less than three months. In the Cuban epidemic at Holguin, where about 12,000 cases of the disease were treated, not a siagle soldier of the well- vaccinated command contracted smallpox, though the men were constantly engaged in sanitary police and in performing guard duty at the lazarettos and infected points. In addition to the prompt searching out, vaccination and isolation of all persons who may have come in contact with a smallpox case, the patient should be carefully isolated. All clothing and other articles exposed to contagion, which cannot be readily disinfected, should be burned. During the stage of desquamation, fixation of the contagious matter should be ac- complished by smearing the skin with olive oU, vaselin or carbolii;ed gly- cerin. All discharges from the nose, mouth and elsewhere should be re- ceived into vessels containing a disinfectant solution. The scabs which have fallen off should, as far as possible, be collected and burned. Isola- tion should be maintained until the last scab has disappeared. The sur- roundings of a case of smallpox should be carefully disinfected. No special prophylactic precautions on the part of the attendants, provided they are thoroughly protected by vaccination and are in a healthy physical condition, appear to be necessary DISEASES OF THE SOLDIER. 733 Vaccine Material. — If the supply of vaccine virus be inadequate, the arm-to-arm inoculation of material from vaccinia pustules, provided due care is used in the selection of the subjects, is of advantage, and, if properly carried out, may be rendered largely free from justifiable criticism. This method was employed during the Civil War. The use of boviue virus is, however, always preferable. Where crusts or charged poiats of this material are used, the virus is unavoidably contaminated with pyogenic bacilli, which, on inoculation, may produce mixed infections of considerable severity. It being practically impossible to produce a vaccine virus originally free from bacterial contamination, the germs unavoidably present should hence be sub- sequently destroyed or rendered harmless. This is readily done by the use of chemically pure glycerin ; and virus stored in this substance for three or four weeks is rendered practically sterile as far as extraneous organisms are concerned. The modern method of preparing glycerinated pulp-vac- cine, much to be preferred for the military service, is given by Copeman as follows : A calf of suitable age, about three to six months old, is kept in quar- antine for a week, after which, if it appears healthy and no reaction is given to tuberculin, the preparation of which has been described in a previous chapter, it may be removed to the vaccinating station. It is there placed on a tilting-table, and the lower part of the abdomen, as far forward as the umbHicus, is shaved, washed with a 2.5 per cent, solution of carbolic acid and then rinsed with sterile water and dried with soft sterilized towels. With a sterilized sharp scalpel, incisions parallel to the long axis of the body are then made on this clean-shaven area. The depth of the incisions should be such as to pass through the epidermis and open the rete Malpighii, if possible without drawing blood. As these incisions are made, glycerinated calf-lymph, which by examination is known to be free from extraneous organisms, is run into them by means of a sterilized blunt instrument, and the point of the scalpel is also from time to time dipped in the vaccine emulsions. After five days, or one hundred and twenty hours, the vaccinated surface of the calf is first thoroughly washed with warm water and soap, rubbed over it by the clean hand of the opera- tor, and finally the whole area is cleansed with sterile water. The remain- ing moisture is then removed by sterilized sheets of blotting-paper. The vaccinated incisions will now appear as lines of continuous vesicles raised above the surface, each line separated from its neighbor by about one-fourth inch of clear skin. Any crusts which appear in the vesicular lines are picked off with a blunt sterilized instrument. The vesicles and their con- tents are then removed by means of a sterilized Volkmann's spoon and are transferred to a sterilized bottle of known weight. By going over the lines only once with the spoon, it is quite easy to remove the whole of the pulp without any admixture of blood. The abraded surface is carefully washed and may be dusted with fine oatmeal or starch and boracic powder. Sub- sequently the calf is transferred to the slaughter-house and the carcass is examined with respect to its healthful condition. Should this examina- tion not be satisfactory, the vaccine-pulp from the animal is destroyed. The bottle containing the vaccine-pulp is then taken to the laboratory and the exact weight of the material ascertained. A calf vaccinated in this way wiU yield from 18 to 24 grams, or even more, of lymph-pulp. This 734 THEORY AND PRACTICE OF MILITARY HYGIENE. material is then thoroughly rubbed up ia a sterilized mortar or in a trit- urating machine. When it has been brought to a fine state of division it is mixed with six times its weight of a sterilized solution of 50 per cent, chemically pure glycerin in distilled water. The resulting emul- sion is then transferred to small test-tubes, which are then asepticaUy sealed and stored in a cool place protected from light. When required for distribution, the emulsion is drawn up into sterilized capHlary tubes which are subsequently sealed in the flame of a spirit lamp. As soon as the vesicular pulp is thoroughly emulsified with the glycerin solution, agar- agar plates are inoculated from it, and after suitable incubation for seven days the colonies that have developed on the plates are counted and exam- ined. Week by week this process is repeated, and invariably the number of colonies diminishes with the age of the emulsion ; until at the end of the fourth week after the collection and glycerination of the lymph material, the agar-agar plates inoculated show no bacterial growth. The lymph is then subjected to further culture experiments, and if the free- dom from extraneous organisms is positively demonstrated the emulsion is ready for distribution. The elimination of the extraneous organisms ordinarily occurs by the end of the fom^th week. The only exception to this rule arises when the lymph originally contained a consider- able number of spores or bacQlL of the hay bacillus, or bacillus mesoenter- icus. These organisms are very resistant to the action of glycerin ; but if the precautions detailed are carried out in the treatment of the calf, they may generally be excluded. The duration of activity of glycerinated lymph in all probabUity varies with atmospheric conditions, with the fineness of division of the vesicle-pulp, and, above all, with the condi- tion of the calf itself. Ordinarily, glycerinated lymph may be considered to retain its full potency for ten months and, imder favorable circum- stances, probably for a longer period. In military practice, however, there wiU rarely be a reason for keeping the lymph any such length of time, and conditions of climate and surroundings are usually such that deteriora- tion is rapid. In nearly all foreign armies, vaccine farms form part of the military establishment. In the French army there are five such farms, of which three are located in France and one each in Tunis and Algeria. In our own service, admirably managed vaccine stations have been established in Porto Eico and in the Phihppines, since it was found to be a matter of both great difficulty and expense to secure active vaccine virus from the United States, Japan or other countries. In the stations in the Philippines, the young water-buffalo or carabao has successfully filled the place of the calf for the production of vaccine virus. Vaccinia. — This requires brief mention, in this connection, because of the temporary disability which it often induces in newly vaccinated re- cruits ; the rates thus produced figuring among the most frequent causes bringing about admissions to sick report. As vaccination on the arm often renders it inconvenient for recruits to drill or perform hard labor for a few days, it is customary to excuse such men as present evidence of a special inflammatory action from the performance of a part or the whole of their duties for a few days. A large proportion of such cases receive no special treatment, and are carried upon sick report as being sick in quarters. DISEASES OF THE SOLDIEE. 735 The admissions for vaccinia during the decade 1886-95, amounted to 33.72 per thousand strength, with a constant non-efficiency from this cause of 1.06 per thousand. For the years 1896 and 1897, the rates were considerably lower than for the decade just mentioned. During the year 1898 the admission rate for this affection was increased to 46.80, while in 1899 it was stiU further raised to 65.33. The great elevation in the rates for these two years imdoubtedly depended upon the large influx into the army of previously improtected recruits ; the re-enlistment of old soldiers, with the slight reactions following their re- vaccination, not reduc- ing the admission rate from this cause to the same extent as when the total enlistment was smaller. This, of course, was to be expected in the expan- sion of the army, and is a condition which will obviously adjust itself to its former standards, vmder settled conditions of military strength, in the comse of a few years. In 1899, a death attributable to vaccinia was reported, amounting to a rate of .01 per thousand strength. Examination of the rec- ords, however, shows that six other deaths occurred as a result of septicae- mia following vaccination ; a fact which emphasizes the necessity for the use of a non-contaminated vaccine virus, such as has just been described, and also the importance of observing all antiseptic precautions in the per- formance of vaccination. These deaths, together with the five which oc- curred among the volunteer forces in 1898, undoubtedly depended upon the use of a contaminated virus, such as gave rise durtag the Civil War, in many instances, to serious results following inoculation with matter from crusts or scabs from human sources. The untoward results just noted are no argument in favor of non-vaccination, but they speak forcibly in favor of a proper technique in carrying out the operation and the use of glyceri- nated and uncontaminated virus. Tuberculosis. Occurrence. — Tuberculosis is a disease which originates more frequent- ly in garrison than among troops in active campaign; but, on the other hand, the arduous nature of the service required under the latter conditions is often responsible for the rapid development of a previously latent infec- tion. The disease is fairly common among soldiers, a fact not strange when its great prevalence among the civil population is considered. It is prob- ably true that a proportionally greater number of cases of tuberculosis occur among soldiers than develop among males of the mOitary age in civil life, in spite of the former originally being physically sound men ; but, on the other hand, the disease is of a somewhat chronic nature and not usually amenable to such treatment as can be given in the military service, and hence the discharge of well recognized cases does much to depress the rates for the military service and raise to some extent those for civil life. Military service appears afford not only to greater facilities for contracting the disease but also much more certainly to develop an existing though quiescent infection. The mortaKty from tuberculosis was extremely high among troops at the beginning of the present century, but has gradually decreased down to the present time as a result of more attention to their welfare. In our own service, the admission rates for tuberculosis, during the Civil War, 736 THEORY AND PRACTICE OF MILITARY HYGIENE. amounted to 6.22 per thousand strength; the death rate to 2.53. During the second year of the war the admission rate was 9.38 and the death rate 3.05. For the period of peace 1868-84, the admissions amounted to 4.83 per thousand strength, and the deaths to 1.05. For the decade 1885-94, these rates feR to 3.39 and .59 respectively; and for the period 1895-98 they were still further reduced to 2.83 and .42. As compared with those given for other armies, these rates are low and reflect much credit upon the care given to our troops ; but their existence, even at present figures, implies a certain laxity of sanitary administration. The death rate from this dis- ease should be made to approximate zero through a more prompt and thor- ough elimination of those affected with it, while a higher physical standard in respect to recruits would do much to reduce the subsequent admissions to sick report from this affection. In foreign armies, figures with respect to the occurrence of tuberculosis, as given by Marvaud and contained in recent official reports, are as follows : Germany Austria.. England. Eussia . . . Italy . . . . Spain . . . Period. 1873-1879 1881-1891 1891-1897 1878-1881 1889-1891 1893-1897 1870-1883 1885-1890 1888-1897 1890-1897 1875-1881 1882-1891 1886-1891 Admissions per 1,000 strengtb. 4.3 5.7 3.57 4.2 4.7 1.76 6.1 3.5 3.7 4.2 3.16 3.82 7.75 The death rates from this disease in the Russian and French armies are particularly high, being 1.6 and 1.10 respectively. The lowest death rate is given by the Belgian army, in which, as a result of careful elimination of the tuberculous, the rate was but .35 per thousand strength in 1898. For the year 1897, the death rate was .45 in the German army. Among the British troops on colonial service, during the decade 1888-97, the low- est rates of admission were given by Gibraltar, 1.9, and Bermuda, 2.4. The highest rates were given by the troops in India, 4.2, and in Ceylon, 4.1. For the Spanish army in Cuba, in 1897, the admission rates for tuberculosis were stated to have been in excess of those for yellow fever, dysentery or typhoid fever. Cause, — Tuberculosis results from invasion of the system and later development of the bacillus tuberculosis. This bacillus is a slender, rod-shaped organism; staining homogeneously in fresh cultures but pre- senting a beaded appearance in old cultures or in sputum. The bacillus is non-motile and has not been shown to form spores. It possesses the property of retaining certain stains, even when subjected to the action of comparatively strong decolorizing reagents. It is stained by Gram's method. The bacillus cannot readily be cultivated on ordinary nutrient media, but may be grown on blood-serum, nutrient agar, and bouillon to which gelatin has been added — developing only at body temperature. It. DISEASES OF THE SOLDIER. 737 is killed by heat at 55° C, but is not destroyed by ordinary drying or by freezing. In the dry state it is much more resistant to heat than when moist. It does not multiply outside the body except in artificial cultures. When grown on blood-serum, the colonies appear, after three or four weeks, as dry, granular, cream-colored, slightly elevated patches with irregular margins. Sometimes these patches become confluent, to form a dense, dry granular mass with irregular surface and of a creamy white color. The growth is very friable, but coherent. On glycerin-agar the growth is simi- lar but not so vigorous ; on glycerin-bouiUon the growth occurs in the form of floating patches, or as a membrane similar in appearance to the growth on blood-serum. Dissemination and Infection.^ — Every tu- berculous soldier is a source from which the dis- ease may be propagated to his comrades. Exactly the manner in which the infectious material is thrown off, depends upon the anatomical location of the tuberculous lesions. Undoubtedly the disease is most commonly disseminated by in- fected sputum, but this is merely because the specific bacilli more commonly find in the re- ^<'- ^^~"'s'„tiSf ^**"" '" spiratory tract the conditions which are favorable to their development. It should not be overlooked that under certain con- ditions the uriae, faeces or discharges from superficial lesions may be pro- portionally as infectious as the sputum. In the sputum of those affected with pulmonary tuberculosis the spe- cific bacilli are usually found ia enormous numbers. Wlien such iofected sputum is dried, pulverised and disseminated as dust by air-currents, the infectious material may be inhaled by those within its sphere of action and may reproduce the disease in susceptible individuals. The same may also occur with respect to tuberculous urine, faecal matter and suppurative dis- charges. In a comparatively dry state the vitality of the bacillus is very great, and it has been shown to retain its virulence for as long as seven to ten months. In the wet state, its virulence is retained for about six weeks ; but in this condition it is comparatively harmless, though not entirely so. Cornet found that the dust in rooms occupied by consumptives contained virulent tubercle bacUli in a large proportion of cases. Such dust, dis- turbed from cornices or out-of-the-way places, even after several months, is often capable of producing an infection, and to its agency the appearance of many cases of obscure origin may be attributed. In a study of con- sumption occurring in Philadelphia, it was found that certain infected tene- ment houses were apparently responsible for a large proportion of cases ; in some instances, every family successively occupying these houses present- ing one or more cases of the disease after an occupancy of any duration. The observations have a practical application to the military service in re- lation to the disinfection of barracks. While the breath in consumptives does not appear to convey the in- fection, fresh tuberculous material may readily be transmitted to food or drink by unwashed hands or similar agency, and give rise to the disease when taken into the alimentary tract. In ten examinations of the hands of hospital attendants in wards where consumption was being treated, 47 738 THEORY AND PRACTICE OF MILITARY HYGIENE. Vigoura found the tubercle bacilli present in two instances. In the same way, infected individuals who cough over food may also disseminate the affection. Flies feed greedily on tuberculous material, and their impor- tance as carriers of the specific bacilli has only recently been appreciated. Much important evidence on this point has lately been collected. Spill- man and Haushalter examined flies and fly excreta from a hospital ward and found tubercle bacilli in both. Hoffman examined the intestinal con- tents of flies taken from a room where a death from phthisis had recently occurred, and found the bacilli in four out of six instances, as well as in the excreta on the walls and furniture. Guinea-pigs inoculated by him with fly intestine became tuberculous. Alessi fed flies with phthisical sputum and then produced tuberculosis in rabbits inoculated with their dung. It is thus apparent that food may be readily contaminated by flies, carrying infectious material. Tuberculous meat may also be a cause of the disease ; and in civil life, milk from diseased animals is not infrequently infected. Clothing or other articles, when infected, may convey the dis- eaee to those persons who handle them, and in such instances the disease not rarely appears to result from accidental infection by way of the ali- mentary tract. Inoculation through a breach of the skin has often oc- curred, but such method of infection is not common in the military service ; when it does occur, the tuberculous process is usually localized at the site of infection. Direct infection from the sick is comparatively rare, but there is evidence to -the effect that the disease may be transmitted from the sick to the well. In instances of this sort, however, the affected individuals have usually not been free from the possibility of infection by indirect means also. Predisposing Causes. — Tuberculosis occurs in all countries and cli- mates, but is especially prevalent where sudden changes of temperature and damp atmosphere favor the occurrence of bronchial irritation; the tuberculous element being thus engrafted upon a simple benign affection. A dry, equable, sunny climate does much to prevent the occurrence of this disease, and the same may be said with respect to altitude. Tropical ser- vice favors the disease; thus in 1899 the rates of admission were 4.52 for the tropical islands and 3.18 for troops in the United States, while the dif- ference in death rates was even more marked, being .67 and .36 respec- tively. The immediate transfer of cases developing in the tropics, to favor- able climates in this country, is imperative. The so-called tuberculous diathesis is of the greatest importance in determining the liability to the occurrence of this disease. There seems to be no doubt that certain individuals present a hereditary susceptibility to tuberculosis, and this predisposition may generally be recognized by its well-known physical signs. Among these, chest capacity is important, and it is of interest to know that in the German army, where the chest of a soldier does not properly develop under physical training, the man is regarded as predisposed to phthisis and returned to civil life. Eace exerts a considerable influence on the occurrence of tuberculosis, though no race is exempt. The negro and Indian are especially predis- posed to this disease. In 1898 and 1899, the admission rates for colored troops were 4.59 and 4.20 respectively; for white troops during the same years they were 3.65 and 3.96. Among the Apache Indian prisoners re- DISEASES OF THE SOLDIER. 739 moved, a few years since, from Arizona to the damp climate of Alabama, the annual death rates per thousand strength, for five years, were 55, 51, 110, 146 and 110 — almost wholly from tuberculosis. For the white race, nativity seems to be not without influence in modifying susceptibility to this disease. In the United States army, for the seven years 1890-96, the ad- mission rates for tuberculosis, per thousand strength, were 3.33 for Ameri- can whites, 2.97 for soldiers born in Ireland, and but 1.49 for those of German birth. In the examination of 501,068 recruits for the Union forces during the Civil War, Baxter states that rejections for tuberculosis were more frequent in blonds than in men of dark complexion ; and that the proportion of rejections for this cause increased directly with the height. Age is a factor of great importance in the occurrence of the disease. For the period 1890-96 the admissions for tuberculosis in our army, per thou- sand of each class, were proportioned as follows : Period. Admissions. 19 years and under 5.03 30 to 24 inclusive 3.44 25 to 39 " 3.09 Period. Admissions. 30 to 34 inclusive 2.69 35 to 39 •' 3.70 40 to 44 " 1.87 The rates for infantry are slightly higher than for cavalry and artillery, and nearly three times as high as those for the Medical Department ; the latter showing the beneficent effect of lessened exposure and freedom from over-crowding. For the period 1890-96, the admissions were about two- thirds as frequent among officers, 1.98, as among enlisted men, 2.96. Kothing is better established with regard to tubercle than its relation to over-crowding and bad ventilation. As long ago as 1858, it was shown in the British army that the troops which suffered the most from over- crowding presented the greatest amount of tuberculosis. The custom of living in common, as in barracks, greatly favors the occurrence of tubercu- losis; since where infection of a squad-room has occurred, all the occupants are equally exposed to the danger of contracting the disease. Casemates, from their dampness, defective ventilation and want of sunshine, particu- larly favor tuberculous infections among troops quartered in them. No more striking example of the influence of such habitations on the frequency of tuberculosis has been given than that reported by Davy in 1862, as wit- nessed by him at Fort Clarence, in England. At this post, converted into a lunatic asylum, the deaths from tuberculosis among insane officers and soldiers' wives, they being lodged in ordinary houses, furnished 19 and 18 per cent, respectively of the mortality from all causes. Among the soldier lunatics, who were quartered in casemates, tuberculosis caused 39 per cent, of all deaths. Bissell has recently shown that infected clothing will long retain dangerous qualities. This observer soaked in water small pieces of cloth removed from the pocket-lining of overcoats, worn by members of the National Guard discharged for tuberculosis, and almost invariably produced this disease in guinea-pigs on injecting them with the resulting fluid. A susceptibility to tuberculosis may be developed, in individuals ordinarily resistant to the disease, through insufficient and improper food, want of exercise, poor ventilation and uncleanliness of the person and surroundings. As with other infectious diseases, any circumstance which tends to lower the powers of vital resistance favors invasion. Prophylaxis. — In the military service, the prevention of tuberculosis 740 THEORY AND PRACTICE OF MILITARY HYGIENE. depends primarily upon the careful selection of recruits and the avoidance of enlisting such as appear to have a predisposition to this disease. If such have been enlisted, they should be discharged. All soldiers affected with the disease should be promptly eliminated from the service, as their retention is a menace to others. The cures which may be obtained at the army sanitarium at present maintained for the treatment of this disease,, can scarcely be regarded as permanent with the conditions of hardship and climate under which such previously infected men, returned to duty, will probably be required to serve. Among other measures of prevention may be mentioned the location of barracks on dry, elevated, sunny sites ; the provision of sufficient cubic space, proper lighting and thorough ventilation ; the avoidance of sharp corners or projecting ledges upon which dust can collect, and the rendering of floors, impermeable with paraffine.. Spitting on the floors and walls of buildings, aside from its being an offense against neatness and decency, should be prohibited for sanitary reasons in connection with this disease. Metallic cuspidors of a pattern readily cleansed should be provided, and should contain a small quantity of some odorless disinfectant solution so as to- keep the sputum in a moist condition. These receptacles should be cleansed and scalded daily. Box cuspidors containing sawdust, as too- often found in barracks, should never be employed. They are not only a danger to health but are often ignited by cigar and cigarette stubs. In the routine cleaning of barrack -rooms the use of dusters should be avoided ; all dust should be removed from shelves and projecting ledges by means, of damp cloths. It should not be forgotten that a squad-room which has contained a case of tuberculosis is not safe for occupancy by others until disinfected. Meat from tuberculous animals should be rejected for issue. An abundant diet containing a considerable amount of fat appears, to be of value in the prevention as well as the treatment of this disease. Chilling and exposure, which favor bronchitis and pleurisy, predispose to tuberculosis and should be avoided. Systematic exercise in the open air,, especially such exercise as increases the mobility and capacity of the chest,, is desirable. With reference to the measures to be applied to the affected individual, the disinfection of the sputum and other discharges from persons suffering from various manifestations of the disease is of the most importance. The patient should be impressed with the fact that he is at aU times a possible source of infection, and that it is quite within his power to control the spread of the disease to others, and perhaps to avoid re-infection in his own case, by proper attention to a few simple details which in no way interfere with his comfort. Special spit-cups should always be provided for the sick ; since otherwise while endeavoring to use the ordinary receptacles on the floor they will frequently cause the contamination of the latter. When the spit-cups cannot be used, clean rags or rice-paper napkias may be em- ployed, and these subsequently destroyed by fire. Bed or body clothing, soiled with tuberculous material, should be at once removed and disinfected. The clothing or bedding of the tuberculous should never be used by the well. All blankets should be frequently sunned, and great care taken to prevent their being shaken under circumstances which would allow the dust to be inhaled or become a means of infection to others. The tuber- DISEASES OF THE SOLDIEE. 741 culous individual should be provided with separate eating utensils, and these should be disinfected after use ; the uneaten portions of food should be burned. All personal contact between the healthy and the tuberculous is to be avoided as much as possible. Typhus Fever. Occurrence. — An entire chapter might be devoted to the historical pathology of typhus or spotted fever. The disease is as old as the disputes of nations and has occurred in formidable epidemics among troops in the field from antiquity down nearly to the present time. Dm'ing peace it has always been of comparatively subordiaate importance, although its occur- rence in armies has given rise, from time to time, to disastrous outbreaks in the neighboring civil population. It is known to have prevailed during the Peloponnesian war; and in 1489 it destroyed 17,000 of the troops of Fer- dinand at the siege of Grenada. In 1528, at the siege of Naples, over 6,000 of the French nobility lost their lives from typhus in a period of about three weeks, and the French army of 30,000 men was almost de- stroyed. In 1542, in the German army at Ofen, according to Hauser, typhus claimed 30,000 victims. Before Metz, in 1552, the besieging Spanish army lost 30,000 men in less than two months, compelling the abandonment of the siege. The roads taken by the retreating army were said to have been lined with the dead and dying. In 1586, it decimated the army of Maximilian II. ; in 1620, the Bavarian troops serving in Bo- hemia lost over 20,000 men from spotted fever. In 1628 and 1632 the disease ravaged the Swedish army. Both the Eoyal and Parliamentary armies in England, in 1643, suffered severely from typhus; in the wars of Louis XIV. it caused enormous losses in the French army. At the siege of Torgau in 1760, it is said that over 30,000 men, out of a total of 35,000, died of this disease in a few months. Typhus is reported as having been one of the great factors in the mortality of our troops during the Eevolution ; and in 1790 the losses among the Eussians from this disease were so great that operations against the Turks had to be suspended. In 1799, typhus decimated Genoa and the French force besieging it. The greatest recorded ravages of this disease, however, occurred during the later wars of the first Napoleon. At Saragossa, out of 100,000 people, 54,000 are reported as hav- ing died, chiefly from epidemic typhus. At Dantzic and WHna, and during the retreat from Moscow, vast numbers of French troops perished from typhus. In May, 1812, the Bavarian allies of the French mustered 28,000 men — in February, 1813, it is said that this disease had left of this num- ber but 2,500 to bear arms. In August, 1813, the first Prussian army of 60,000 men had lost one-sixth of its strength from an epidemic of typhus. Murchison states that in Mayence alone, of the 60,000 French troops com- posing the garrison in 1813, no less than 25,000 died of typhus in six months. According to Eawlinson, of the French armies around Paris, after the retreat from Eussia, 40,000 men died of typhus in six weeks — one-fifth of the remaining force being sick. This disease raged in all the contending armies during the Crimean War, particularly among the French troops. Aitken says: "In the spring of 1856 it was computed that more than 17,- 000 men of the French force perished in less than three months, chiefly 742 THEOEY AND PRACTICE OF MILITARY HYGIENE. from typhus." Baudens declared that of the typhus cases in hospital in February, 1856, two-thirds were devoted to certain death. The deaths among the French medical officers during this outbreak amounted to 48, and there was said to have been scarcely one that escaped attack. Typhus undoubtedly did not occur among our troops during the Civil War, although a small number of cases were diagnosed as this affection. It prevailed among the French troops in Mexico, especially on board the ships which conveyed the native forces, from northern Africa. Cous- tan says of these troops that they "suffered a cruel loss." In 1862-63, and again in 1867, typhus attacked the French garrisons in Algeria; Mar- vaud stating that of one body of 3,500 troops, 1,200 died from this dis- ease. Its existence during the Franco-German War in 1870-71 is dis- puted. During the Russo-Turkish War in 1878, it was said that one time the cases of typhus were so numerous in the Turkish army as to threaten its disorganization, and the conditions in the Eussian army were not much better. After the capture of Plevna, according to Coustan, 50,000 men out of a total of 120,000 died during the period of inactivity, and in May and June of 1879 it is stated that half the Eussian forces near Constanti- nople were prostrated with this disease. Typhus fever, in the military service, is essentially a disease of camps and sieges. Of late years, the affection has lost much of its importance to the military sanitarian. Its geographical distribution is not great ; and at present, in time of peace, it occurs only among troops stationed in south- eastern Europe, where the disease is endemic. In the Eussian army, for the period 1890-97, the rates per thousand were as follows: Year. Admissions. Deaths. Tear. Admissions. Deaths. 1890 0.6 .9 1.8 0.04 .07, .14 1894 0.7 .3 .3 .2 05 1891 1895 ... 03 1892 1896 02 1893 1897 02 In the Austrian army there were 9 cases in 1897, 4 in 1896 and 8 in 1894. There has been no weU-authenticated outbreak of this disease in our own army within the past half-century. A number of localized epi- demics of typhus have, however, prevailed in the civil population of the country, the infective agent being in every case imported from abroad. Direct and Predisposing Causes. — ^The specifio exciting cause of typhus fever has not as yet been isolated ; it is said that the disease has recently been experimentally produced in Eussia by inoculation with the blood of typhus patients. It is universally admitted that the most im- ^portant influences predisposing to its epidemic occurrence are want, misery and hardship. Typhus appears to be largely favored by over-crowding and lack of proper ventilation; cold weather, as shown in the Crimean War, probably indirectly promotes its occurrence among troops for these rea- sons. Viry notes that typhus was prevalent in public institutions in the city of Metz, in 1870, when it did not appear among the French troops living in shelter-tents just outside the walls. Poor food, dampness, fatigue and other conditions lowering the resistive powers — together with psy- chical depression — have much to do with epidemics of this disease. DISEASES OF THE . SOLDIER. 743 Typhus fever is highly contagious, in the strict sense of the word ; and there is probably no disease which has been more frequently contracted from the sick by their attendants. Thus at Plevna, nearly all the medical officers were attacked; while during the Crimean War 12.8 per cent, of the medical officers and only .4 per cent, of line officers, among the French troops, died from typhus. As with smallpox, the specific virus appears to be distinctly transmissible from the sick to the well through the surround- ing atmosphere, and infection appears to take place by way of the air passages. The poison may be harbored by and carried from place to place in fomites. Jacquot, in speaking of typhus during the Crimean War, says that " wherever troops affected with typhus have camped, the dejections and excretions which have saturated the ground are fatal to troops which follow them." The morbific agent appears long to exist in infected cloth- ing and dwellings. The activities of the specific virus are favored by unsanitary conditions ; and where the disease is introduced among troops which are poorly nourished and insufficiently clothed, and living under conditions implying over-crowding, there is every likelihood of an epi- demic outbreak of the fever. The incubation period is variously stated at from six to fourteen days ; though there appear to be some well authenti- cated cases in which it was not more than two to five days. The disease is most common during the period of youth and early maturity, as found in young soldiers, but the mortality is lower than among those of greater age. Prevention. — It is manifest that the prophylactic nieasures against the disease are those that aim to prevent its introduction from without, and those that are designed to eliminate all local CQnditions favorable to its development. Quarantine against, infected points should be rigorously maintained. Where the disease appears among troops in garrison, the sick and well should promptly be placed imder canvas ; for , the influence of fresh air upon the virulence and vitality of this disease is undoubtedly flf the highest importance. The command, if large, should be broken up into smaller bodies. Especial attention should be given to the prevention of over-crowding, to ensuring an abundance and proper preparation of food, to the avoidance of fatiguing exercise and to the maintenance of strict san- itary police. Careful watch should be kept for suspicious cases- and these should be at once isolated as they appear. It should not be forgotten that the aggregation of large numbers of the sick greatly increases their rate of mortality, as well as the danger to the attendants. Tent hospitals should preferably be used, the supply of fresh air being unlimited and the floor space allowed to each patient being about two hundred square feet. The tent devised by the writer presents particular advantages fpr the treat- ment of infectious cases of such character. As the contagion is especially vu'ulent near and about a patient, attend- ants should as far as possible avoid inhaling the emanations from the sick, vmless protected by a previous attack. They should not stay in the imme- diate vicinity of typhus patients longer than necessary, and should never sleep in a ward. They should take plenty of sleep and good food, and should frequently employ disinfectant solutions on the face and hands. The attendants, like the sick, should of course be quarantined. Careful disinfection of excreta and of bed and body clothing is always called for. 744 THEORY AND PEACTICE OF MILITAEY HYGIENE. The barracks or ward, as well as all articles of furniture, clothiug or equip- ment contained in it, should be disiufected and thoroughly aired after removal of the patient. Yellow Fevee. Occurrence. — Yellow fever is essentially a disease of tropical and sub- tropical countries, and within these it is ordiuarily restricted to well-defined geographical limits and, to a considerable extent, to the summer or rainy seasdn. Bodies of troops serving within these limits of infection for any length of time, during the yellow-fever season, have uniformly been more or less afifected by it. In 1648, "there occurred in Havana, and in the fleet of Don Juan Pujados, a great pest of putrid fevers. A third part of the garrison and a larger part of the crews and, passengers in the vessels died." The disease was extremely fatal among the British troops which captured Havana about three centuries ago ; and it is interesting to note that the regiment of loyal Americans recruited for this expedition, largely from the southern part of the country, was least affected. In 1740, in the expedition against Carthagena, its effects were most disastrous. In 1780, a force of 8,000 Spanish soldiers was landed at Havana, and within two months had lost 2,000 men from this disease. In 1794, "the vomito ap- peared so severely that solely of the garrison (of Havana) and of the squad- ron more than 1,600 victims were taken. It was indispensable to resort to a general levj' to replace the- losses on the vessels." In Hayti, during the rebellion of the blacks, the French army of veteran soldiers was practically annihilated by yellow fever. Of this epidemic, Lemure wrote: "In 1802 an army under the orders of General Leclerc embarked for San Domingo. The effective strength, on leaving Brest, was 58,545 men. In four months 60,270 men were dead; chiefly of yellow fever, which gave 82.5 per cent, of the total mortality. Of the 8,275 men remaining, 3,000 were sick or wounded. In 1809, seven years later, this army was reduced to 300 men, who returned to France." The French also suffered from yellow fever during their occupation of Mexico. According to Coustan, there were 1,705 cases; the fever breaking out six days after the landing at Vera Cruz. During the Civil War there were, in the Union forces, 1,371 cases and 436 deaths; and in 1867 fie disease attacked a number of south- ern posts and caused 1,520 cases with 453 deaths. For the period 1868- 84 the disease recurred almost annually among such of our troops as were stationed in the south ; the average for the whole army for this period, per thousand strength, giving a rate of .78 for admissions and .33 for deaths. For the period 1885-96 inclusive, there were no cases of yellow fever in our service. In 1897 there were 7 cases with 3 deaths; in 1898, at Santiago, there were 604 cases with 70 deaths, For the period 1868- 98 the rate for admissions from yellow fever was 1.17 per thousand strength, and for deaths .26. The Spanish army in Cuba has always suffered severely from this disease, especially during the epidemics of 1876-77 and 1896. The British and French troops which have been stationed in the West Indies have also been repeatedly attacked. Cause and Mode of Dissemination. — With regard to the nature of the materies morbi of yellow fever nothing is as yet known, though inves- DISEASES OF THE SOLDIER. 745 tigations by many medical officers of our service have been, and are now being, vigorously prosecuted. Eeed and Carroll, of the United States army, have recently shown that the mosquito is at least one of the most important agents by which the transmission of the disease is accomplished. Not every species of mosquito serves as a carrier of the infection, however, and, as with malarial disease, a special variety of suctorial insect serves as the intermediate host. This variety, for yellow fever, is the so-called Culex tiniads of Giles, but is classified by Theobolt in a new genus, Stegamina. The first-named ob- servers showed that while yellow fever may be transmitted to the non-im- mune individual by means of the bite of the mosquito which had previously sucked the blood of those sick with the disease, an interval of about twelve days in warm weather and eighteen days in cool weather was apparently necessary before the infected mosquito became capable of transmitting the infection. This period doubtless represents the time required for the para- site of yellow fever to pass from the stomach of the insect to its salivary glands. The bite of the infected mosquito at an earlier period after con- tamination, while not provoking an attack of the disease, does not appear to confer any immimity against a subsequent attack. While yellow fever may be experimentally produced by subcutaneous injection of blood taken from the patient during the first and second days of the disease, it has been deter- mined that an attack of yellow fever produced by the bite of an infected mosquito confers immunity against the subsequent injection of the blood of an individual suffering from the non-experimental form of the disease. A most thorough series of experiments by these observers showed that the excreta of the yellow-fever patient were not directly infectious to sus- ceptible individuals exposed to their influence, and hence the disinfection of articles of clothing, bedding or merchandise is not believed by them to be necessary. This view, of course, assumes that the mosquito is unable to take into its organism any infective material present in fomites, and that the infectivity of this insect depends wholly upon its withdrawal of blood from yellow-fever cases. This point remains as yet to be demon- strated. As with malarial fever, common experience would seem to show that the parasite of yellow fever must certainly be able to maintain an extra-corporeal existence independent of the mosquito and man, and not depend upon a short cycle through these two hosts alone. Many epidemic outbreaks have apparently followed the introduction of articles infected by yellow-fever patients into districts in which the disease had been unknown prior to that time ; and until the dietary capabilities of the species of mos- quito in question have been accurately determined, it would be the part of wisdom to destroy any possible infectious element in articles contaminated by the secretions of the sick. The food of the mosquito family is very varied and is known to include vegetable matter and fresh blood — a piece of fresh raw meat hung up where mosquitoes have access to it being greed- ily attacked by them. Should the discharges in yeUow fever contain the specific micro-organism, as would seem to be at least probable, it may be that the mosquito, after feeding on the bloody vomit and stools, acquires infective properties as regards the transmission of the disease as readily as if the blood were sucked by the insect directly from the yellow-fever pa- tient himself. Certainly such a hypothesis is reasonable, and would tend 746 THEOEY AND PEACTICE OF MILITARY HYGIENE. to explain many of the phenomena connected with the outbreak and spread of this disease. , Within the yellow-fever belt, infected habitations have long been re- garded as the chief points from which the disease is spread, and it has not been considered that the yell-ow-fever patient, removed to good surround- ings, was as much to be feared as the place in which the sufferer contracted his infection. Experi- ence has shown that 'those in attendance on the sick in hospitals are not especially liable to contract this disease ; and yellow-fever pa- tients have not rarely been treated in general wards among suscept- ible patients without the disease being com- municated to the latter. The investigators above named believe that a house is infected with yellow fever only when there are present within its walls contaminated mosquitoes capable of conveying the parasite of this disease. From the long period through which such infectivity often persists in dwell- ings which have shel- tered yellow-fever cases — far longer than the life of the mosquito — the specific germ of the disease would, however, appear to retain its viru- lent qualities even if the transmitting agent, in the form of the mos- quito as an intermediate host, were absent. Without the latter to serve as the means of inoculation the disease, of course, would not occur among the inmates ; but the possi- bility of its later transmission, as a result of the admission of mosquitoes, iminfected at the time of entrance, should not be ignored. The fact that infection by yellow fever usually occurs at night, when mosquitoes are most active, has been abundantly demonstrated. During outbreaks in some southern cities, men who were at their places of business during the day, but who went out of town to sleep, were largely exempt from the disease. >- a: < < 3 o: 03 UJ T O a. < S -1 (T O. < 5 2 z 5 D « 3 (3 3 < (£ U m S 111 £ UJ w UJ CQ O t- o o £ m lij > o z EC UJ CQ I s Q 12.00 11.(10 11.20 10.80 10.40 10.00 9.(10 1..0 8.80 8.40 800 7.60 7.20 A. 80 fi.40 T7 ^/. 0.00 '/. ^/ 5.60 ^ 6.20 'A 4.S0, ^A -'z '/■ .4.40 /' ■'z T7 It: 'A 'A 4.00 ■/. 'A. y- A, /a 3.60 /A i'. ,- A A/ 3.20 ^ AA ■A, -; '' A, y^ 2.80 '> --< (' ■/. ^- W, 2.40 '^■ . ■/■ '' 2.00 ^/ . -•/, f^; ; ■A '/■ ■, '/ ,- '' j.oo ■/' ■. 'A 'A -"/ '/ ', ^', A' ^ '< 1.20 ^^ y- ' A, '/- 'A 'A ■> y '- z ^y 'A 0.80 ■ ■ 'y. 'y- , {■'■ 'A. 'a H ^K" . . y- ^- '/' 0.40 "■" ~H '/.*■" > ; ^ '^ '/. '/■ 'a>. y. 0.00 ■'/tK~ ^tH 7:fl y9~ 'a •/, ■> ^/ ^ fS <9 ^d ^« '/. _ '± 'A ^ 'A 1870-77 13M- FIG. 354.— Distribution by Months of DeuLtis from Yellow Fever In the Spanish Army In Cuba, per Thousand Strength, during the Epidemics of 1876 and 1896. DISEASES OF THE SOLDIEE. 747 The incubation period is short, ranging clinically from one to five days ; the experimental attacks induced by Reed and Carroll had an incubation period ranging from forty-one hours to five days and seventeen hours. The accompanying diagram well shows the relative prevalence of yeUow fever, distributed according to months, in an endemically iufected region ; it win be noticed that the disease is by far the most common during the months of greatest raiafall, when the propagation of the mosquito is favored by an abundance of water and constantly damp soil. Years ia which an unusual amount of rain is noted are those in which the rates for yeUow fever are above the mean. In dry years, on the contrary, the rates are low, and cold weather, with its inhibitory effect upon the activities of the mosquito, terminates the outbreaks of the disease, at least during the continuance of the former. Absolute immunity to yellow fever is not possessed by any peoples as a racial characteristic; though, relatively speaking, those adults who are permanent residents in the endemically infected zones exhibit much less liability to contract it than do strangers newly arrived from colder latitudes. In general terms, it may be considered that among adults the susceptibility to, and mortality from, yellow fever varies directly with the distance from the equator of the place of nativity and residence of the individual. Ac- cording to Barton, of each 1,000 deaths from yellow fever which occurred in New Orleans in the epidemic of 1853, the distribution of mortality was as follows : Native Creoles 3.58 Strangers from West Indies, Mexico and South America 6. 14 Strangers from Southern United States 13.33 Strangers from Spain and Italy . 33.06 Strangers from Middle United States. 30.69 Strangers from New York and New England 32.83 Strangers from Western United States 44.33 Strangers from France 48. 13 Strangers from British America 50.34 Strangers from Great Britain 53. 19 Strangers from Germany 132.01 Strangers from Scandinavia 163.26 Strangers from Austria and Switzerland 330.08 Strangers from the Netherlands 328.94 Long ago Blair wrote that among the West Indian islanders in the Seamen's Hospital at Demerara, Guiana, the percentage of deaths from yellow fever was 6.9; that of the French and Italians was 17.1; that of English, Irish and Scotch was 19.3; that of Germans and Dutch was 20; that of Swedes, Norwegians and Eussians was 27.7. It has been thought that the Creole and African, irrespective of place of birth and residence, possess a racial immunity to yellow fever. This, however, does not appear to be the case. Such a relative immunity is probably only the result of an attack of the disease itself, which in early life may be so mild as scarcely to be recognized ; or to a much less degree, it may be due to the transmission of a relative insusceptibility from ancestors immunized for generations through attacks of the disease. It should be noted that the immu- nity to this disease indoubtedly possessed by many natives of the yellow- fever belt is more or less completely lost after removal to cooler latitudes, and that such individuals on their return to the zone of endemic yellow fever often exhibit a susceptibflity equal to that of total strangers to the 748 THEOKY AND PRACTICE OF MILITARY HYGIENE. district. There is, therefore, no reason to believe that the negro primarily possesses any greater powers of resistance than does the white man under the same conditions, or that the negro born in cold climates is as insus- ceptible as the negro born and resident in the yellow-fever belt. An acquired or inherited immunity is the essential factor. It should be noted that yellow fever prevailed among the negro troops at New Orleans during the Civil War and caused considerable mortality; for the year 1898, the rates in our army for this affection, per thousand strength, were as follows : Deacbs. White troops . . Colored troops . 9.40 59.19 1.04 7.51 The negroes recruited for our service are rarely drawn from districts in which the disease has prevailed. The great difference in favor of white troops noted above, however, is largely to be explained by the fact that the colored troops of our army were nearly all present during the epidemic of the fever at Santiago, while a much less proportion of the total white .troops was so exposed. Further, one colored regiment, on account of its supposed insusceptibility to this disease, was selected to do guard and police work at the yeUow-fever hospital, thus largely increasing its oppor- tunities for infection. A fair comparison between the susceptibility of the unacclimated white with the negro native to the yeUow-fever zone may, however, be drawn from the statistics for the British troops in the West Indies. For the decade 1888-97 the rates for yellow fever, per thousand strength of these troops, was as follows : • Admissions. Deaths. Constant sicliness. Europeans 3.0 .4 1.66 .15 0.16 Non-Europeans (negroes) .02 Prophylaxis. — In preventing the occurrence of yellow fever among troops, expeditions into an endemically infected district should not be car- ried out in the fever season. Troops intended permanently to garrison infected points will with advantage be recruited from the native and im- mune population. Soldiers should be prohibited from entering infected towns, and particularly from entering houses and shops, especially at night. With this, there should be careful protection against mosquitoes, both by the use of mosquito-nets in barracks and by searching out and destroying these insects in their adult and immature stages by the methods already detailed in connection with the prophylaxis of malarial fevers. Before oc- cupying a buUding in the yeUow-fever zone, it should be fumigated with sulphur dioxide, both to accomplish disinfection and to destroy any insect life which may be present. When an epidemic occurs among the surrounding population, a careful quarantine against the latter should be maintained. With the outbreak of the disease among the troops, aU cases should be promptly isolated, prefer- ably in tents. All discharges from the sick, especially the vomit and excreta, should be disinfected; if possible, by fire. The clothing and DISEASES OF THE SOLDIER. 749 equipments of the soldier, and tliose with which he may have come in contact, should be disinfected, as should the tent or barrack in which the case appeared. If possible, the troops should be moved to a locality in which the fever does not exist, or better, where it has not been known to originate ; in this country, troops have habitually been transferred from southern stations to Atlanta, Ga., when an outbreak of the disease was apprehended. If such a locality is not available, the troops should be moved to high ground — preferably to an elevation of at least fifteen himdred feet. Moving camp even a mile or so may avert an epidemic, and this pro- cedure should preferably be repeated with the appearance of every new case ; for a district once infected remains so until cold weather puts an end to the outbreak. Abandonment of an infected area is essential — a fact repeatedly demonstrated m our own military service; as at Fort Brown in 1882 and at Santiago in 1899. As laid down by Sternberg: "The precautions re- lating to food and to personal habits do not differ materially from those with reference to cholera. The diet should be simple, and excesses in eating or drinking avoided. Nothing is more likely to favor an attack than alcoholic excesses, or to bring about a fatal result if the disease de- velops. Exposure to the direct rays of the sun, excessive fatigue and venereal excesses are 'all predisposing causes which it is within the prov- ince of individual prophylaxis to avoid. Exposure to the night air, and especially sleeping out of doors near the ground, is recognized in yellow- fever regions as an invitation to attack. Great care should be taken to avoid chilling of the body, and it is well to sleep as far above the ground as possible." Whether in camp or garrison, general prophylactic measures of importance have reference to careful sanitary police, free ventilation and avoidance of over-crowding. A predisposition to the disease appears to be caused by fatigue, especially when combined with exposure to the sun, by drinking and by insufficient or improper food. If the disease appear on board ship, the vessel should be searched for mosquitoes, and the sick should be treated on deck and landed as soon as possible. No prophylactic medi- cation is known to be of value. Various methods of preventive inoculation have been devised, notably by Freire and SanareUi, but experience has shown these to be without effect. General PunfciPLES of Prophylaxis against the Infectious Diseases. As a science, prophylaxis owes its development from the empirical to the rational to the results of modem bacteriological research. In the great majority of diseases, the etiological is no longer an unknown factor. Its importance, nature, habitat and r6le are well understood, and, with the possession of such exact knowledge, the application of measures calculated to terminate or modify its existence becomes readily feasible. Scientific prophylaxis has therefore as its cardiual principle an intimate knowledge of first causes. It undertakes to obtain an accurate knowledge of both the predisposing and exciting factors in disease, and, through logical methods, to remove or destroy them. It aims at an avoidance of contact with infec- tious matter, endeavors to prevent a condition of susceptibility to disease on the part of the individual and at the same time attempts to destroy or 750 THEORY AND PRACTICE OF MILITARY HYGIENE. modify such conditions of environment as favor the existence and perpetua- tion of pathogenic micro-organisms. Its first object is attained through early recognition of the nature of infectious disease, the isolation of the sick, the maintenance of quarantine and by the avoidance or abandonment of in- fected places ; its second purpose being accomplished by the observation of all such measures as tend to stimulate and strengthen the powers of vital resistance. For its third object, in preventing the existence and propaga- tion of infectious germs outside the body, prophylaxis manifests itself in aU that is implied in the term" disinfection. At the risk of slight repetition, the chief means of preventing or controlling infectious disease among troops, outside of the processes of disinfection, wiU. be given a general con- sideration in this connection. Early Diagnosis. — In preventing the spread of infectious disease among large bodies of men, an early and acctirate diagnosis of each case is of the first importance; since it is evident that the institution of special measures of prophylaxis necessarily depends upon a recognition of the existence of an affection of a character rendering such action advis- able. Sanitary officers should be prompt to realize that the early cases of an infectious nature, in the absence of proper precautions, are very possible forerunners of a serious epidemic, and as such demand far more serious, consideration than the slight morbidity from such a cause would at first sight appear to warrant. The simultaneous introduction and wide dissem- ination of a large number of pathogenic germs is by no means essential to the origination of an epidemic, however much it may favor its occurrence. The history of infectious disease is full of instances of epidemics which have developed from a single and long unrecognized, focus of infection; and in this connection, the rapid multiplication of bacterial life under favorable conditions should not be overlooked. An affection, the nature of which is for some time undetermined, may from this reason gain such a foothold among troops as to render its subsequent control a task of vast proportions, if not, indeed, almost impossible. Hence the importance of arriving at a prompt diagnosis in all cases of a possibly suspicious charac- ter, in order to justify' the carrying out of well-known and demonstratedly efficient measures of prevention, which are so ready and easy of applica- tion in the individual instance. Isolation. — As a measure of general prophylaxis, the soldier affected with a transmissible disease of grave character is to be removed at once from the camp or common habitation, and should hold communication with only those persons to whose care he may have been entrusted. Un- der such circumstances, every precaution should be taken to render the isolation complete, since even the slightest laxity in its maintenance may wholly defeat the purpose for which the action was taken. His various articles of personal property should also be carefully collected, removed in a manner ealcukted to prevent possible dissemination of the infectious agent through handling, and at once rendered innocuous through approved methods. What applies to the individual is also applicable to the larger num- ber. In campaign, all cases of contagious or infectious disease should promptly be removed from the army as a whole and properly segregated; while organizations in which disease has become epidemic should be de- DISEASES OF THE SOLDIEK. 751 tached en masse from the command, isolated and the sick removed from time to time as their cases subsequently develop. Such infected organiza- tions should never be augmented by recruits — who are particularly sus- ceptible to diseases of an infectious character — nor should they hold any communication with such organizations as are yet mitainted. Troops should not be stationed where infectious disease has existed, unless proper measures have previously been employed for the destruction of the infectious agent. If an error of this kiad has imfortunately been committed, the command which has been exposed should be at once iso- lated and held under careful observation for a time covering the iacubation period of the affection, dating from the time of last exposure. This pre- caution, under similar conditions, should be applied also to the individual. In time of epidemic, suspects, like the sick, are always to be eliminated from the main body ; to meet their needs, special camps or stations for their detention and observation should be provided. Such camps need usually be located at no very great distance from the maia body of troops, provided the regulations as to isolation are rigorously carried out; since unconfined air will rarely be a vehicle for morbific agents and mediate or direct con- tact with the sick is alone to be guarded against. Soldiers who are convalescents from transmissible disease must not be relieved from restriction or returned to their camp or quarters untU it is positive that they are no longer able to communicate their affections to others. With a wider understanding of the exciting causes of disease, a more exact definition of the period during which the sick may transmit their affections has become possible. As a result of this knowledge, the tendency is strongly toward the lengtheniag of the period of isolation ; since the con- valescent may long continue to be the host of the pathogenic organism by which he has undergone invasion. It is the duty of the sanitary officer to determine this period for each convalescent, according to the nature of his illness. The establishment of detention camps, for the temporary recep- tion of convalescents and the relief of congested hospitals, wiU often be found advisable. Unfortunately the necessity for such segregation, learned in the military service by hard experience, is not appreciated by the gen- eral public. The retention under military control of convalescents from infectious disease is often sorely against the wishes of friends and of the patients themselves, who demand permission to complete their cure at home. "Where this has been granted, as during the war with Spain, re- lapses are often frequent, and perhaps also a communication of the disease to new circles in the civil population. With respect to the individual, isolation means more than simple con- finement to a separate room, building or locality. It comprises, in addition to this, the employment of a specially assigned attendant who comes in contact only with those under his care ; the disinfection of all infective ma- terial or discharges as soon as they are passed by the patient and before they can leave the sick-room; the disinfection of all bed and body linen as soon as they are removed from the patient and before they leave his apartment; the provision of separate eating utensils, handkerchiefs, towels and instrumental accessories; the frequent cleansing with disinfectant solutions of the surroundings of the sick ; the frequent bathing of the at- tendant, and especially the careful disinfection of the hands after each 752 THEOEY AND PEACTICE OE MILITAEY HYGIENE. manipulation of the patient. The special methods of disinfection are treated of in detail in the following chapter. Quarantine. — The term quarantine, formerly held to apply to a period of time, is now employed to designate a method by which disease of trans- missible nature is absolutely debarred entrance into a territory, and among individuals, as yet uninfected. There is obviously no fixed period of quar- antine for all cases, but the length of this period varies according to the duration of incubation of the particular disease against the introduction of which the precaution has been taken. Pathogenic bacteria, even if of microscopical proportions, are nevertheless living entities, and as such are capable of being transported and of reproduc- ing, under favorable conditions, after their own kind. Since human beings and articles designed for human use or consumption must be regarded as in most instances the vehicles of infection, the efforts of the quarantine system are chiefly directed toward the prophylaxis of disease through their exclusion whenever they appear to be probable carriers of infectious ma- terial. Quarantine, to be of value, must be absolute; in its results an inefficient quarantine is practically the same as none at all. Whenever the system is instituted, its details should receive the constant supervision of superior authority, for human nature is weak and disease is insidious. Prom the nature of things, a quarantine on land, on a large scale, is ex- tremely difficult of accomplishment — but less so in the military establish- ment than in civil life. AH cases of epidemic disease, as smallpox, which occur within or in the vicinity of the camp or post, should be promptly known to the mUitary authorities and strict measures taken to prevent contact by the troops ; by instructions, orders and, if necessary, the establishment of a sanitary cordon around the infected point. Not only should the actual cases of the disease be quarantined against, but also all persons and things which may have been exposed to the infection. These should be traced out with the greatest diligence by the sanitary inspector; the inanimate objects should be disinfected, while the individuals who have been exposed should be segregated and kept under observation until the period of incubation of the disease concerned has passed. In this connection it is well to remember that places of public amuse- ment, refreshment and recreation, especially such as are in the vicinity of the camp or garrison, are always to be looked upon as possible foci of in- fection. As such, their patronage by troops should be discouraged, and, in time of epidemic, if necessary prevented by the use of military force. Avoidance. — Communicable disease is transmitted by contact — if not- directly with the sick, at least with their secretions, excretions or epithelial detritus — and the avoidance of such contact lies at the foundation of pre- ventive medicine. It should scarcely be necessary to insist upon the ne- cessity, in the prevention of disease in the military establishment, of re- quiring troops to avoid such material, persons, localities or structures as have either certainly or presumably undergone contamination by infectious matter. In the military service, the chances for the propagation of disease through the medium of infected articles are proportionately much smaller than in civil life, while persons sick with known contagious affections are instinctively shunned by all classes alike ; but habitations, particularly in DISEASES OF THE SOLDIER. 753 time of war, are liable to be utilized for shelter by troops without proper investigation of their antecedents — ^the considerations of present comfort for the time outweighing the sense of possible future misfortune. Such a tendency to sanitary error, on the part of both officers and men, is always to be repressed. Should it at any time appear desirable to occupy build- iags not under government control, or such barracks or other structures as may have been deserted by an enemy, it should be ascertained iu advance if cases of contagious or infectious disease have occurred or have been shel- tered therein ; and if so, what measures looking to disinfection have been carried out. On such subjects, general information will be frequently unreliable and misleading, and hence the necessary inquiry should pref- erably be addressed to such competent local authority as may be able to answer correctly and without prejudice. A building which is ascertained to have contained contagious cases should always be viewed with sus- picion, and, if it has not been properly disinfected, should under no cir- cumstances be occupied — even temporarily. If near a camp, and hence a constant menace to the health of the command, such a building should either be guarded against entry by troops, be properly disinfected or de- stroyed by fire. Abandonment. — As foci for the dissemination of infectious disease are always to be removed from a military force, so also the removal of such military force from a locality which appears to have become thoroughly impregnated with infectious material becomes imperative. This procedure must be carried out without delay. Eemoval to even a comparatively short distance is frequently sufficient to cut short serious outbreaks, par- ticularly with regard to yellow fever, malaria and dysentery. If possible, the site selected for the new camp should present such conditions of alti- tude, soil, moisture and surface configuration as are recognized as being unfavorable to the development of the causative agents of the affection which it is desired to escape. In abandoning an infected encampment, all tentage and spare equipment should be left behind for careful disinfection. The men should be required to bathe immediately before deserting the camp ; and such disinfection of the person and clothing as may be feasible should be prescribed. If the movement be to another camp of an intended semi-permanent character, the latter is best prepared in advance for the reception of the troops. The sick and all cases of a suspicious character must be rigorously eliminated prior to the departure of the conamand, and imder no circumstances should they be permitted to accompany it on the march or follow later to the new camp. Provided there be justifiable reason for belief that the infection is so localized that its destruction in this way can be properly accomplished, a practice march of ten days, the troops living in shelter-tents meantime, will afford an excellent opportunity for the application of radical measures of disinfection throughout the temporarily deserted post or encampment. Troops among whom infectious disease is epidemically prevailing, should move camp frequently but should not continue on the march. Fatigue is a marked factor in lowering vital resistance and so directly predisposing to infection ; besides which there would always be the probability of distribut- ing the germs of disease along the route traversed by the command. The scattering of the men in small groups over a wide area constitutes 48 754 THEORY AND PRACTICE OF MILITARY HYGIENE. an excellent means of breaking up and controlling epidemics of disease among large bodies of troops. Individual Hygiene. — As regards the individual, prophylaxis is largely hygienic in its natm'e, and its aims are toward the production or maintenance of such a standard of bodily health as will best resist invasion of the organism by disease. As already stated, infectious germs do not possess the power of unconditionally entering the economy and disturbing its functions. For the production of disease there must be invasion by the special pathogenic micro-organism, together with circumstances permitting its subsequent existence and perpetuation. Hence the maiutenance of health-giving principles, the results of which are manifested in increased vital resistance, is the great object of prophylaxis. The latter purposes to secure this object by suitable hygienic measures, and at the same time to remove or modify, so far as it may be possible, all unfavorable and debil- itating conditions of environment. The health of the individual is powerfully affected by the conditions under which existence is maintained, although predisposing causes of dis- ease may also be present within the organism itself. As a result of sm- roundings, the struggle for existence may be of no great severity, but, on the other hand, they may render the maintenance of life extremely pre- carious. Care devoted to the improvement of environmental conditions in the military service is weU repaid by greater efficiency, and every attention should be given to secure an excellent quality of clothing, proper venti- lation, cleanliness and freedom from dampness of the habitation, personal cleanliness and a sufficiency of physical exercise. Susceptibility to disease varies inversely with the standard of nutrition, and prolonged famine is always followed by pestilence. Hence the pre- vention of disease in the individual will largely depend upon the careful observance of all such measures as are calculated to assist in the nourish- ment of the organism. In time of epidemic, or when such an outbreak threatens, the food supply should be especially varied, abundant, nutritious and stimulant. Special articles of diet, appetizingly prepared, should be issued without particular regard to an increased drain on the company fund, since no financial outlay for such a purpose can compare with the cost of an outbreak of epidemic disease in a large body of troops. Excesses of all kinds, particularly those of an alcoholic nature, should at such times be carefully avoided. It has repeatedly been demonstrated, both by practical experience and laboratory experiment, that prolonged and excessive fatigue exerts a mark- edly depressing effect on the resis^tive powers of the organism against dis- ease. Foreign sanitary officers have long noted an increase in typhoid fever and other affections following the arduous exertion incident to the annual military manoeuvers — an increase which they regard as only par- tially due to the temporary exposure to unusual sources of infection. It is evident, therefore, that during the unusual prevalence of sickness, and par- ticularly in the presence of an epidemic, all drills and fatiguing exercises should be reduced to the practical minimum ; without, indeed, actually condemning troops to that state of ennui and inactivity which m itself may be a strong predisposing factor in the occurrence of disease. Since the mental state exerts a marked effect upon the physical condi- DISEASES OF THE SOLDIER. 755 tion, the spirits of the men should be sustained in every way through healthful amusements and recreation. Sanitary regulations specially ap- plicable to existing conditions are to be duly brought to the notice of the command, but not in such a manner as to excite unnecessary apprehension. The observance of a quiet, calm demeanor on the part of officers, during time of epidemic, is all that will be necessary to insure the maintenance of a similar condition on the part of the men. Above aU things, a condi- tion of mental depression or panic is to be avoided. It should never be forgotten by the sanitary officer that, in carrying out precautionary measures against disease among troops, the chief obstacle to success is found in the carelessness and ignorance of the soldiers themselves. Artificial Immunization. — This means of prophylaxis has already been touched upon, in certain of its details, in connection with several of the infectious diseases common among soldiers ; and it is obvious that no general. discussion of this many-sided and as yet largely imdeveloped sub- ject can be taken up in a work of this special character. There is little doubt, however, that the military sanitarian of the future will find in pro- tective inoculation, as with vaccination, one of his most potent aids in the prevention of infectious disease among troops. Much has already been accomplished along these lines, and there is abundant authority for the statement that "the problems relating to immunity have been, in part at least, removed from the realm of pure hypothesis and placed in a position favorable to exact experimental solution." II. DISEASES LARGELY DEPENDENT XTPON EXPOSTTRE. Bronchitis. This affection, in our army, is one of the most frequent causes whereby soldiers are rendered temporarily incapacitated for duty. Its mortality in young men of the military age, when occurring idiopathically, is, however, small. In the United States service, the admissions for bronchitis, since the year 1860, underwent a certain decrease during the period of peace but were raised by field service, being as follows : i Period. Admissions per 1,000 strength. 1861-66 92.94 1868-84 77.73 1885-94 68.67 Period. Admissions per 1,000 strengtli. 1895-98 75.48 Year 1897 59.73 Year 1898 100.65 Bronchitis may be brought about by a great variety of causes. There are those who regard it as largely due to an invasion of the respiratory tract by some specific micro-organism as yet undetermined, and any irritant gas or dust may produce it. In the military service, however, the evidence is conclusive as to the chief part in its origination being played by expos- ure and cold, particularly the latter. Eeports for our army have for many years shown its greatest prevalence to occur in the more northern military departments and stations ; and the remarkable influence of cold weather in inducing this affection, as determined by months, is well shown ia the accompanying diagram. It would seem to be abundantly demonstrated 756 THEORY AND PRACTICE OF MILITARY HYGIENE. that, for our army, idiopathic bronchitis chiefly results from exposure ta cold; this interrupting the eliminative functions of the skin, whereby an increased duty is thrown on the pulmonary mucous membrane, with its resulting congestion. This hypothesis largely explains the commonly ob- served fact that outbreaks of considerable magnitude not infrequently occur among bodies of troops, which are naturally exposed to the same meteoro- logical and environmental conditions. Age is a factor of great importance in the occurrence of the disease, very young and very old soldiers being par- to -*. f7 K ^S r ■"=^^^1 X ji ' T *Tr' ' 1 ^U <^ f w ^^^^^^' ' A Fig. 357.— Klnyoun-Francls Steam DlsinlectinK Chamber. other, thus securing complete isolation of the infected and disinfected articles. The cars, upon being unloaded, are returned to the working end of the chamber by means of transfer tables. The working of such a sterilizing apparatus may be described as fol- lows : The steam is generated in the boiler at high pressure, and by means of a reducing- valve is led to the chamber at the reduced pressure desired and allowed to circulate in the jacket. Wlien the jacket is properly heated, the infected goods are loaded upon the car ; it is then pushed into the chamber, the door closed and made steam-tight by fastening the bolts with a quick-action ratchet wrench, which draws the door tightly against the rubber gasket in the door frame. In a few minutes the temperature in the chamber wiU. rise, and the vacuum apparatus is started until the gauge indicates about 15 inches vacuum. When the thermometer indi- cates the temperature of the incoming steam, if 10 pounds is used, say, 115° C, the pipes into the inner chamber are opened sHghtly at first, giv- ing whatever direction of circulation is desired, and when the pressure has risen, the steam-pipes are closed and the vacuum pump brought into action until the vacuum gauge shows 7 inches. The vacuum pump is then shut off and the steam pipes are opened ; the steam being allowed to circulate through the chamber at 3 to 5 pounds pressure and this circulation being maintained for the period of the exposure, when the by-pass valve is 774 THEORY AND PRACTICE OF MILITARY HYGIENE. opened wide to exhaust the steam. It can then be closed, and the air pump once more started to eliminate the dampness ; then the door on the opposite end is opened and the car removed and unloaded. The steam chamber and disinfecting plant should be located in an outbuilding, weU. provided with doors and windows and divided by a tight partition. The apparatus itself should be so placed that its opera- tion should be easy, while there should be no risk of a re-infection of steriUzed articles through contact with non-disinfected material in removal from the steam chamber after completion of the operation. From this danger such types of apparatus as are furnished with only one door are not free; to render such secondary contamination impossible, not only should the apparatus have two doors for entrance and removal respectively, but the room in which the infected articles are received should have no com- munication except through the open air with the room in which the steri- lized articles are removed from the disinfectiag chamber. It is scarcely Fia. 358.— Ground-Plan Arrangement for Quarantine or Large Disinfecting Station. necessary to say that the two doors of the steam-chamber should never be opened simultaneously. There should, of course, be two sets of attendants to handle the soiled and disinfected articles respectively. A special movable apparatus for disinfection by steam under pressure might, with advantage, be supplied to each military department or to each army corps, as is the case in several European armies. This disinfector, while nominally attached to some large field hospital or military post, could be temporarily placed at the disposal of such organization as might require its services and would undoubtedly serve an excellent purpose, particularly in relation to troops ia the field or during time of epidemic. The Kinyoun-Francis wheeled disinfecting apparatus was devised as a result of the problems presented in various epidemics of yellow fever in our southern cities. The apparatus consists of a beam frame mounted upon running gear, carrying the chamber, pump, coal and water tank and the locker-box seat. The chamber is composed of double steel shells, with a door at one end, handled by a crane attached to the chamber itself, and has a removable track, with a stand adjustable for the irregularities of the roadway, with a galvanized car of sufficient si^e to take single or double mattresses. The piping is so arranged as to give thorough control of the steam circulation, and has a reducing-valve, thermometer, vacuum and pressure-gauge and safety-valve. The boiler and pump are easy of access for working and are arranged compactly. In its method of operation the DISINFECTION. 775 portable steam-disinfecting apparatus closely resembles that of the fixed disinfecting plant, made by the same company, as just described. Plants for disinfection by steam under pressure have the disadvantage of implying a considerable original outlay, as well as of requiring the ser- vices of a specially instructed mechanic for their manipulation. They fur- no. 359.— Klnyoun-Francls Steam Disinfecting Wagon. nish, however, the best method of accomplishing the disinfection of cloth- ing, bedding and similar articles, and when viewed from the standpoint of the sanitarian, their increased cost and expense of maintenance are scarcely worthy of consideration where large hospitals, camps or posts are con- cerned. It is probable, also, that attendants of sufficient ability to take charge of such disinfecting plants would readily be found among the enlisted strength of the army and so diminish the expense of operation. CHEMICAL DISINTECTANTS. The chemical substances used for purposes of disinfection are, for aU practical purposes, limited to such as can be employed either in gaseous state or in aqueous solution ; since when existing in dry solid form they can scarcely be brought into that intimate relation with all portions of an object which is required for its disinfection. The essentials of a useful and trustworthy chemical disinfectant, as enumerated by Abbott, are : It must be a germicide — having the property of destroying bacteria and their spores. It should be so constituted that its germicidal properties are not destroyed by the extraneous matters in which the infective organisms that are to be killed are located. With ordinary care, it should not be directly poisonous to those who use it. It should, if possible, be without disagreeable odor, should be cheap in price, easy to manipulate, and for particular purposes should not cause permanent stains or be destructive to the skin, fabrics or other articles to which it is to be applied. In many cases it is not possible to explain the manner in which disin- 776 THEORY AND PRACTICE OE MILITARY HYGIENE. fection is accomplished by chemical agents, any more than to say that the microbes are poisoned by the disinfectant ; though ia particular instances this is accomplished by a union between the disinfectant and the proto- plasm of the bacteria ; in others there seems to be a coagulation of the albuminoid constituents of the bacteria, while in others disinfection is ac- complished through the disintegrating influence that the disinfectant has upon the bacteria. While a large number of chemical substances are known to possess germicidal properties in greater or less degree, and hence may be variously employed in civil life for purposes of disinfection, the scope of this volume will necessarily preclude the discussion of such as are not officially issued for use in the military establishment of the United States. Bichloride of Mercury. — HgCl^. Bichloride of mercury, known also as mercuric chloride or corrosive sublimate, is soluble in 3 parts, by weight, of bo ilin g water or in 16 parts of cold water. It is also readily soluble in alcohol. An aqueous solution of ammonium chloride wiU. take up corrosive sublimate more readily than wiU water alone, a soluble double chloride (sal alembroth) being formed. This solution with ammonium chloride is very efficacious in the extermination of insect vermin, and is much employed for that purpose. In its activity as a germicide, corrosive sublimate undoubtedly stands at the head of all chemical substances; a solution of 1-1000 strength promptly destroying bacteria together with their spores, a proportion of 1-10,000 being slightly germicidal and even a strength of 1-40,000 mark- edly restraining the development of micro-organisms. Its field of appHca- bUity is somewhat limited, however, by the fact that it rapidly attacks and corrodes metals, and that it unites with albimien in the formation of an in- soluble albuminate possessed of practically no germicidal value. Modifica- tion of the first property being impracticable, all metaUic objects should be promptly removed from its possible sphere of influence. Coagulation of albumen, however, may be largely prevented by the addition of a small pro- portion of acetic or tartaric acid to the sublimate solution. Wherever contact with albuminous material is liable to occur, the precaution of adding one of the above organic acids must be carefully observed, since, in the use of all chemical disinfectants which precipitate albumen, it must be understood that a part, or even the whole, of the active agent may be neutralized by contact with the albuminous material with which pathogenic bacteria are usually associated; while, at the same time, through the envelopment of these bacteria in an insoluble covering, a mechanical protection against their destruction is created. Upon long standing, and particularly upon prolonged exposure to air and sunlight, corrosive sublimate in solution has a tendency to undergo reduction to mercurous chloride or calomel — a substance of no practical efficiency for purposes of disinfection. It is therefore advisable to add to its solution about 0.2 per cent, of hydrochloric acid; thus not only increas- ing the stability of the solution, but also increasing its destructive proper- ties toward such micro-organisms as are unfavorably affected by an acid medium. According to Vignon, ordinary water ultimately causes the decom- jMDsition of the bichloride of mercury through the mineral and organic matter which it contains ; hence such solutions should be freshly prepared and DISESTFECTION. 777 rapidly utilized. In the presence of considerable amounts of calcium and magnesium salts this reduction is rapid and may even be complete, en- tirely destroying the value of the solution as a disinfectant. The use of hard waters in connection with mercuric chloride should, therefore, be carefully avoided, even though a previous boiling may remove a certain portion of the salts from the water it is desired to utilize. Distnied water should be employed for solutions wherever practicable, but in its absence rain-water will give satisfactory results. In the lack of water suitable for use with the mercury salt, reliance should be placed upon other disinfec- tants rather than in the employment of solutions of this substance which are necessarily of unknown strength and hence of doubtful efficiency. Corrosive sublimate solution is extremely poisonous and at the same time possesses neither characteristic appearance nor odor ; hence it is always well, in diminishing the dangers of its use, to add a sufficient amount of permanganate of potash or methylene blue to impart a noticeable color- ation to the solution. Mercuric chloride is rapidly removed from its solution by clothing. According to Kubla, a small piece of cloth soaked in 250 c.c. of a 1-1000 solution deprived the latter of its mercury in a few minutes. Similar re- sults have been obtained by Sclavo and Mannelli, who found also that textures of animal nature removed corrosive sublimate from its solution much more readily and completely than cloths of vegetable origin. It is therefore advisable, in the disinfection of clothing by bichloride of mer- cury, to employ solutions of considerable strength; and, where articles are successively being treated by this agent, the renewal of the solution should be frequently practised. For all the purposes of disinfection to which it can be applied, the acid solution of bichloride of mercury, liaving a strength of 1-1000, must be regarded as standard. Carbolic Acid. — C„H,OH. Carbolic acid or phenol is manufactured from that part of the heavy oil of coal tar which boils between 150° C. and 200° C. It is somewhat heavier than water, and crystallizes in long needles, having a solubility in cold water of about 6.5 per cent. — or about three times that of "Tricresol." It becomes pink or brown on long stand- ing, from the presence of some impurity. For many years well known and widely employed as a germicide, carbolic acid has of late been largely displaced for purposes of disinfection by various other chemical substances of equal if not greater germicidal powers, and possessing in less degree the several properties which render tlie use of carbolic acid always unpleasant, somewhat dangerous and slightly uncertain. The disinfectant properties of carbolic acid are so well recognized at the present day that any discussion thereon would seem to be superfluous. It is an active germicide; less so than was at one time supposed, but still sufficiently potent to satisfy the requirements of actual practice. A great disadvantage to its use in large quantities is the strong, disagreeable and lasting odor which accompanies its application. For purposes of disinfection, carbohc acid is used in solutions of three to five per cent, strength by weight, care being taken to secure its solution by agitation and by the use of warm water. When employed in such a 778 THEORY AND PEACTICE OF MILITAEY HYGIENE. strength, it has a wide range of applicability and gives generally satisfac- tory results in the disinfection of excreta, articles of clothing, objects of wood, leather or metal and for the disinfection of the walls and floors of habitations. A practical disadvantage in its use is its comparatively high price, even when the crude acid is employed, as compared with that of some other germicidal substances. In order to obtain its germicidal action, its solution must be thoroughly mixed with the matters to be disinfected so that it comes in intimate contact with them. Crude carbolic acid and concentrated sulphuric acid, when mixed in equal parts, form a compound readily soluble in water and possessing germicidal properties superior to those of pure carbolic acid alone ; the em- ployment of the crude acid for this purpose is preferable to that of the re- fined substance. Obviously the uses to which this compound can be put are more restricted than those of carbolic acid alone. Tricresol. — The name " Tricresol " is a trade designation, applied for commercial purposes to a mixture of ortho-, meta- and paracresol. This cresol group forms the next higher homologue to phenol ; one atom of hydro- gen in the latter being replaced by the methyl radical CH3. The group is metameric with benzyl alcohol. Ortho- and paracresol are crystalline bodies having a low melting-point, while metacresol is a thick, colorless fluid. " Tricresol " is manufactured from coal tar, and is a white liquid having a specific gravity of about 1.045, possessing a strong pungent odor and a solubility in cold water of about 2.55 per cent. According to Eeed, a one per cent, solution of "Tricresol " wiU infal- libly destroy the pus-producing micro-organisms in half a minute ; a pro- portion of 1-800 beiDg sufficient to restrain development. The presence of albuminous matter in fluids to be disinfected does not interfere to any serious extent with its prompt and certain germicidal action ; an exposure of one and one-half to two minutes to a strength of one per cent, sufficing for sterilization. A proportion of one per cent, appears to be adequate for all purposes, and in comparing carbolic acid and " Tricresol " it would ap- pear that the latter, bulk for bulk, is about three times as powerful a dis- infectant. It should not be forgotten that, in equal quantity, " Tricresol " possesses toxic properties as great as those of carbolic acid. Lime.' — CaO. Lime, quicklime and calcium oxide are synonymous terms. The substance occurs in whitish, amorphous masses ; odorless, alka- line and caustic. It is produced by heating the carbonate of calcium and so reducing it to the oxide. Calcium oxide combines with about one-third its weight of water, with the evolution of considerable heat and an in- crease of bulk, in the production of powdered calcium hydrate or water- slaked lime. If a larger quantity of water be employed, the so-called " milk of lime " results, a solution temporarily holding an indefinite excess in suspension. When treated with 700 parts of cold water the hydrate is wholly dissolved to a clear solution, which is "lime-water." If exposed to the atmosphere, quicklime is rapidly acted upon by the carbonic acid and moisture of the air, and, when completely air-slaked, is decomposed into a mixture usually containing something over fifty per cent, of calcium carbonate and something less than fifty per cent, of calcium hydrate, ac- cording to the amount of moisture present in the atmosphere. As the for- mer substance is of no utility for purposes of disinfection, the necessity for DISINFECTION. 779 insistence upon the employment of freshly -burned lime, not more than four or five days from the kiln, water-slaked, becomes evident. If freshly burned lime cannot for any reason be supplied at the point where disinfec- tion is required, its shipment should be made in small lots, well packed to exclude air and moisture. Since 1890 the use of lime as a disinfectant has been officially sanc- tioned in the armies of France, Germany and Great Britain. The value of this substance as a disinfectant depends upon its caustic alkalinity. It may be used in a dry state as well as after slaking; but under the former condition a much greater quantity is required and the results are not usu- ally as satisfactory. Being extremely cheap and at the same time not a powerful germicide, it should always be added to the infectious matter in large excess or until the mixture is strongly alkaline. MOk of lime, as officially prescribed for use in the army of the United States, is to be prepared by the addition of one part, by weight, of the freshly hydrated lime to 'eight parts of water. In its application to quantities of faecal matter the milk of lime is to be employed in the proportion of five per cent, by bulk; with a daily addition equal to ten per cent., by bulk, of the estimated increment of faeces. According to this method of employment, to each 95 parts of faeces there is added .62 part of water-slaked lime — or 1 part in 153. This would seem to be an extremely small proportion for a substance of no very powerful germicidal powers, particularly in the absence of thorough mixing with the infectious material or with the deterioration of the lime through atmospheric influences, which is so liable to occur. In view of the extreme cheapness of quick -lime, and to avoid any possible failure in the attainment of disinfection, it will do no harm to err upon the side of safety and considerably to increase the strength of the milk of lime as prescribed above. Most modern authorities recommend that mUk of lime be made by adding one part of lime to four parts of water. The quantity of lime used should, of course, always bear a definite ratio to the bulk of the infectious material to be disinfected. A perfunc- tory sprinkling of infectious matter with weak milk of lime, as is so often done, is a procedure worse than useless — since it accomplishes little or nothing in the way of disinfection and at the same time engenders a feel- ing of false security. Quicklime has but a slight effect in the destruction of odors and requires some little time for the accomplishment of disinfec- tion, often several hours. Where milk of lime is used for the disinfection of faeces, it should not be thrown into a water-closet without dilution and the flushing of the trap, since otherwise the thick mass may accumulate and stop the pipes. Whitewash is a thickened mixture of quicklime and water to which, to increase its cohesive powers, sizing is sometimes added. Wherever lim e is employed for purposes of disinfection, it should be freshly burned — ■ and its use in whitewash is no exception to this rule. Too often a white- wash is composed chiefly of calcium carbonate, which possesses no germi- cidal properties whatever. Giaxa found that ordinary whitewashing with hydrated lime destroyed aU micro-organisms except the spores of anthrax and the bacillus of tuberculosis. Lapasset obtained excellent results, in disinfection by whitewashing, by mixing five parts of water with two parts of quickhme and then adding an equal quantity of boihng water contain- 780 THEORY AND PRACTICE OF MILITARY HYGIENE. ing five per cent, of sizing. To increase the germicidal action of ordinary- whitewash, a small proportion of chlorinated lime is sometimes added in the preparation of the former. Prior to the application of whitewash to a surface, aU. loosely adherent dirt or lime should be removed by scraping; the actual removal of a large proportion of the bacterial life being preferable to its burial under a coating of whitewash. This scraping, however, should be carefully done and every precaution taken not to promote, by this very action, the dissemination of the micro-organisms throughout the habitation. Chlorinated Lime. — CaCLOCl. Chlorinated lime or bleaching powder, popularly miscalled "chloride of lime," is a white powder of pecul- iar chemical composition and somewhat unstable nature, resulting from the exposure of moist calcium hydroxide (water-slaked lime) to nascent chlorine gas — about 56 per cent., by weight, of the latter substance being absorbed. Chlorinated lime is an excellent desiccant and a powerful deodorant, vigorously attacking and decomposing hydrogen sulphide and? volatile ammoniacal compounds. As a disinfectant, its valuable properties have been established by the researches of Sternberg and others. Its efficiency as a germicide depends upon its available chlorine, of which, as prescribed by the United States Pharmacopoeia, at least 25 per cent., by weight, must be present. It undergoes decomposition on exposure to the air, through liberation of its chlorine by the carbon dioxide of the atmosphere, and hence should be stored in closed vessels in a cool and dry place. In its slow decom- position, chlorinated lime is liable to lose a small proportion of its oxygen in the production of true chloride of lime (CaCl^) which, by its affinity for moisture, lenders the bleaching powder deliquescent. Chlorine, when slowly evolved from bleaching powder, unites with the carbon dioxide of the atmosphere in the formation of hypochlorous acid — an even more powerful disinfectant than chlorine itself. As a disinfectant, chlorinated lime may be directly applied ia the dry state. Equally as good results, however, are obtained by its use in strong watery solution and the method is much more economical The addition of water to chloriaated lime is generally admitted to yield a mixture of calcium hypochlorite (CaClOJ, calcium chloride (CaCl,) and some cal- cium hydrate (CaOHJ; of which latter substance a large quantity re- mains as an undissolved residue. The efficiency of this solution as a disinfectant depends chiefly upon the presence of the calcium hypochlorite, which is readily decomposed, even by carbonic acid, with the liberation of hypochlorous acid. This acid itself, when exposed to light, is decomposed into chloric acid and free chlorine. For use in the disiufection of rooms, Chamberland and Fernbach advise the preparation of a solution of chlori- nated lime made by covering one part of the bleachiag powder with an equal amount of water. After standing an hour the mixture is filtered and a greenish-yellow liquid obtained; one part of this solution being added to ten times its volume of water for application to the surface to be disinfected. As a result of their investigations, it is claimed that this weak solution is fully as efficacious for purposes of disinfection as a stronger one. If possible the solution should be applied hot, and the room which is being disinfected should also have its temperature elevated. A solution of good DISINFECTION. 781 chlorinated Hme in water in the strength of one-half to one per cent, by weight has been shown to disinfect typhoid and cholera stools in ten min- utes, while a one per cent, solution will destroy the anthrax bacillus ia two hours. Thorough mixing of the chlorinated lime solution with the mate- rial to be disinfected is essential. Its use is without danger to the operator and it leaves no poisonous residuum in the room disinfected. In the United States army, a four per cent, strength of chlorinated lime in solu- tion is officially prescribed for use in the disinfection of the excreta of the sick ; it being specifically stated that the chlorinated lime so used should be of good quality and not have undergone deterioration. The disagree- able odor resulting from the use of chlorinated lime in rooms may be re- moved by hanging about cloths soaked in strong soda solution after disin- fection is complete. The Hypochlorites. — The employment, for the purpose of disinfec- tion, of , calcium hypochlorite — CaClO^ — has aheady been noticed in connection with the use of chlorinated lime in watery solution. La- barraque's solution, or a solution of sodium hypochlorite — NaClO — ap- pears to be somewhat less actively energetic than the solution of calcium hypochlorite, and as it is also more costly the employment of the latter is. preferable. Its germicidal properties of course depend upon the amoimt of chlorine available on the decomposition of the sodium salt. Labarraque's, solution may contain as much as six per cent., by weight, of chlorine, and the standard of the United States Pharmacopoeia requires that it shall contain no less than 2. 6 per cent. For purposes of disinfection one part of the solu- tion is usually added to four parts of water — but in practice sodium hypo- chlorite is employed almost exclusively for the disinfection of the person. In this connection the disinfectant solution prepared from sea-water may be noted ; the chlorides normally present being converted into the. hypochlorites by electrolysis. A plant for the production of this disinfec- tant solution, under the trade name of "Electrozone," was put in practical operation in the municipal sanitation in Havana while under control of the United States military authorities. It was claimed that the sea-water so treated had an average chlorine strength of 0.16 per cent. The solution was distributed in wagons for use in disinfecting sewers, street sprinkling- and household disinfection. It was shown by Eeed, however, that the chlorine strength claimed was not obtained in practice, and in observa- tions covering a period of ten days the available chlorine in the electro- lyzed sea-water varied from a maximum of 0.142 per cent, to 0.021 per cent. A chlorine strength of less than 0.15 per cent, cannot be rehed upon for prompt disinfection, and a solution containing a minimum of 0.25 per cent, is desirable. Eeed therefore concluded that the "Electrozone" as used in Havana did not possess sufficient strength for efficient and rehable disinfection. His experiments showed that a solution of sodixnn hypo- chlorite of equal chlorine percentage is just as effective in germicidal action as electrozone, and the same is true of chlorinated lime to which enough of hydrochloric acid has been added to free the whole of the chlorine. Com- paring the relative cost of production, Eeed found that ordinary chlori- nated lime solution of a definite and constant disinfectant value could be supplied much cheaper than "Electrozone," which had no particular stand- ard of strength. 782 THEOEY AND PRACTICE OF MILITARY HYGIENE. Ferrous Sulphate. — FeSO,. Ferrous sulphate, also called sulphate of iron or copperas, occurs in green, efflorescent crystals, readily soluble in twice their weight of cold water. On account of its inferior germicidal powers as well as its property of staining fabrics, the employment of sul- phate of iron is practically limited to its application to faecal matter, for which purposes its marked capacity for the destruction of bad odors ren- ders it particularly suitable. It is extremely cheap, easy of application and, unlike other substances, does not impair the fertilizing value of the matter to which it may be appKed. The properties of ferrous sulphate which render it useful for purposes of disinfection depend upon its tendency to appropriate oxygen and so become converted into the ferric sulphate. These qualities, however, must be considered as antiseptic rather than disinfectant, since, according to Laveran, the addition of even five or six per cent, of the salt to faecal matter is unable uniformly to effect the steriliza- tion of the latter. Sulphate of iron is used only in solution ; the amount of the iron salt to be daily employed depending upon the estimated increment of the fresh fsecal matter rather than upon any particular strength of the solution. Should the contents of the latrine be semi-fluid, the solution of sulphate of iron may with advantage be made up with but a small proportion of water, since for efficiency a high proportion of ferrous sulphate should be brought into direct contact with the excreta. In practice, a proportion of five parts of the iron salt in each hundred of the total contents of the latrine vault should be considered as essential to efficiency. In the French army, fer- rous sulphate is much used for the disinfection of latrines in a ten per cent, solution. It is officially laid down that at least 250 c.c. of such a solution should be used per day for each person using the latrine. Chemical Disinfection by the Use of Sprays. — Various types of ap- paratus for the projection of disinfectant solutions, in a finely divided spray, have been largely employed in the disinfection of buildings; more so iu Europe than in this country. All are much alike in structural detail and in results obtained. Late models are lined with ebonite or hard rubber, to permit the use of corrosive sublimate solutions without iuducing the dete- rioration of the apparatus, and are sometimes mounted on wheels so as to allow of their more ready transfer from place to place. The nozzle of the apparatus is not of the ordinary "rose" form, but is constructed on the same principle as in the small hand atomizer; the fluid being aspirated into and projected by a strong current of compressed air. For the use of these sprays two men are required, one to direct the jet of spray and the other to work the pump. The spray apparatus delivers the disinfectant solution with considerable force and in the form of a fine, almost invisible mist. The walls are not sluiced down, but the extremely minute globules are intended to remain adherent to the wall without coalescing into large drops. Even with the fine division of the disinfectant spray it is, how- ever, difficult to obtain a general microscopical moistening, and to secure the best results the nozzle must be held at the distance of only a few inches, not more than four or five, fi-om the surface to be disinfected. To determine the completeness with which a surface is moistened at any distance, a simple and ready test consists in the projection of colored fluid from the spray apparatus against white paper, and the subsequent ex- DISINFECTION. 783 amination of thfe latter with the aid of the microscope. "With the use of the spray a much smaller amount of disinfectant solution is naturally re- quired than if the walls are washed down, although the quantity varies largely according to the character of the surface treated. With the Geneste- Herscher apparatus a single quart of solution will moisten an oil-painted surface of sixty square yards ; although for walls generally, most of which are porous and absorbent, an average of about two quarts for each three square yards will be required. It is not possible satisfactorily to spray hot solutions, since heated liquids are rapidly cooled by the act of pro- jection itself. According to Laveran, the difference in temperature shown Fio. 360.— Apparatus for Disinfecting Walls by tlie Use of the Spray, as Used In the French Army. by a thermometer sprayed at the nozzle of the apparatus and again at the distance of one meter was 31° C. ; the thermometer in the last instance registering a temperature somewhat lower than that of the surrounding au". The use of the spray apparatus for wall and ceiUng disiafection is a great economy of labor. With a hand-brush and solution, a workman can disinfect about sixty square yards of surface per hour ; while with an ato- mizer from ninety to two hundred square yards, according to the height, conformation and porosity of the wall, can be thoroughly sprayed in the same time. On plastered or calcimined walls most bacteria are rather resistant to the action of the disinfectant — much more so than on painted walls. On papered surfaces the results are frequently unsatisfactory. After spraying with a solution of mercuric chloride of 1-1,000 strength, Esmarch noted a great diminution ia the number of the germs present but rarely a complete sterilization, the spraying being continued until large drops of the solution collected on the wall. As a result of extensive experi- ment he concluded that the use of the spray was followed by too uncertain results to render its employment of practical utility and gave inferior results to the method of disinfection by rubbing down the walls with stale bread. The use of 1-1,000 bichloride solution as a spray gave Laveran no very gratifying results, and even in the strength of two and four parts per thou- 784 THEORY AND PEACTICE OF MILITARY HYGIENE. sand the results were not always positive; the baciLLus of anthrax always proving resistant and other common pathogenic micro-organisms frequently being undestroyed. It is well to note, however, that Laveran removed the corrosive sublimate at once after spraying so as to avoid its inhibitory ac- tion in cultures subsequently made, and it can be readily understood that a more prolonged exposure in situ might have resulted in the actual destruc- tion instead of the inhibition of the micro-organism. Opposed to the above a^e the favorable results obtained by Guttman and others in the use of the spray with strong acid corrosive sublimate solution; a solution con- taining three parts of bichloride and five parts of hydrochloric acid per thou- sand being recommended. As a whole, the results obtained with the spray apparatus appear to depend upon the distance at which the operation is car- ried out, the duration of the spraying, the nature of the material in which the microbes may be embedded, the amount of fluid projected and to a large extent upon the character of the wall. It appears to be amply de- monstrated that with the use of a strong germicidal solution, sprayed from a short distance for a considerable period, reliable results may be antici- pated. For sluicing down the walls, in the absence of any special apparatus, the use of the ordinary cheap spray-pump, such as is used for spraying flowers or washing carriages, will answer all purposes, provided no solution destructive to the metal, such as bichloride of mercury, be employed. Such a pump is cheap, light and small and can be worked by one man. Formaldehyde in watery solution is now much used in the form of a spray for the disinfection of small articles, it appearing to give more cer- tainly positive results than follow the use of other germicidal solutions by atomization. In its employment, due care must always be taken to use an amply effective strength, erring on the side of safety if at all. To leave no doubt as to the thoroughness of the results obtained, it is safe to say that no solution containing less than 2.5 per cent, of formaldehyde gas should be employed. A strong solution of formaldehyde appears to exert no more of a dele- terious effect upon the articles to be disinfected than do weaker solutions, and hence the only question concerns a possibly slightly increased financial outlay. Articles such as carpets, clothing or hangings may be satisfactorily disia- fected by spraying with a solution containing ten per cent, of " formalin " (four per cent, of formaldehyde gas) ; care being taken to continue the operation for some minutes and to make sure that the spray has reached all portions _ of the surface or fabric. As a matter of fact, it is Fig. 36i.-Formaiiii Spray usuaUy extremely difficult to remain in the room cKBoaVdlffH/air ^^il the Completion of the operation of spraying; the operator finding it necessary frequently to with- draw temporarily to the purer air outside. Stahl found that clothing and similar articles could be made germ-free by spraying with solutions containing one-half to two per cent, of formaldehyde gas, provided they were sprayed some little time — ten to twenty minutes — and that the ap- plication of a solution containing as little as one part of formaldehyde in twenty-five thousand was sufficiently powerful to prevent bacterial develop- DISINFECTION. 785 ment. In employing formaldehyde solution as a spray, it is well to re- member that it hardens the unbroken skin, rendering it rough, whitish and anaisthetic — while on abrasions it produces a burning, painful sensa- tion and ultimately induces superficial necrosis. Blankets and bedding, if used too soon after spraying with such a solution and without sufficient au-ing, may induce bronchitis and considerable uTitation of the conjunctiva. The use of a spray of " formalin " (40 per cent, formaldehyde) for the dis- infection of all the surfaces and articles in a closed space, as weU as the 8iu:faces actually moistened, is now habitually employed in room disinfec- tion by the Chicago board of health ; the procedure depending for its gen- eral efficiency upon the formaldehyde gas evolved. For every thousand cubic feet of space in the room is suspended, by one edge, an ordinary bed sheet (two by two and one-haLE yards) from a line stretched across the middle of the room. Properly sprinkled, this will carry without dripping five ounces of "formalin "- — which is sufficient to disinfect one thousand cubic feet of space. As many sheets as may be necessary are used, hung at equal dis- tances apart. The ordinary, rather coarse cotton sheet should be employed in order to secure rapid volatilization. Care should be taken that the spray is very fine and that the edges of the drops do not touch each other, for if the sheet is actually wet the solution evaporates slowly and produces the solid paraform, instead of passing directly into the air as formaldehyde gas. The sprinkler used by the Chicago boai'd of health is perforated by eight minute holes one-fom-th of an inch apart and about one millimeter in di- ameter. The container will hold twenty-two ounces of formalin, sufficient for four sheets or enough to secure the disinfection of four thousand cubic feet of space. The results obtained by this process ai'e very satisfactory ; and its simplicity, freedom fi-om danger and lack of bullvy or expensive ap- paratus render it especially adapted to the needs of the military service. GASEOUS DISINFECTANTS. The ideal disinfectant is a gas, prompt in its action and certain in its results, which, readily penetrating to all parts of a confined space, wiU. permeate articles to be disinfected without deterioration of their qualities. Non-toxic to the higher forms of life, it should be capable of ready gener- ation, easy manipulation and absolute conti'ol. It should be a good deo- dorant, and if its possess an odor itself it should be one capable of rapid dissipation. A considerable number of gaseous substances have been at various times employed for pm-poses of disinfection, but, with the exception of chlorine, sulphur dioxide and formaldehyde their use in the military estab- lisliment, as in civU life, has been definitely abandoned. Some of these once vaunted disinfectants, as, for instance, the vapor of boiling viaegar, have been demonstrated to possess no germicidal value, while others, as bromine, iodine and nitrogen dioxide, have been discarded by reason of then- poisonous and destructive properties and the difficulties attending then- manipulation. These latter substances possessiug, at the present time, a purely theoretical interest, any consideration of other than the thi-ee first named is unnecessary. Chlorine. — 01. This body, first used in 1774 for pui-poses of room 60 786 THEOKY AND PRACTICE OF MILITARY HYGIENE. •disinfection, is a greenish-yellow gas, possessed of characteristic and dis- agreeable odor, rapidly corroding metals and having an intensely irritant ■effect upon animal tissues. In its employment every precaution against its respiration should be taken, since if inhaled in even weak proportion it may produce spasm of the larynx, severe bronchitis and even death. Chlorine in considerable volume may be generated by mixing 18 parts, -by weight, of fine table salt with 15 parts of pulverized binoxide of man- ganese and adding a mixture containing 45 parts of commercial sidphuric ■acid and 21 parts of water. Evolution of the gas, at first rapid, becomes gradually slower but may be hastened by the action of gentle heat. It may also be prepared by adding 4 parts, by weight, of strong hydrochloric acid to one part of manganese dioxide. Chlorine is readily produced by the action of any acid, no matter how weak, upon chlorinated lime or bleaching powder. While chlorinated lime theoretically contains about 56 per cent, of chlorine, that proportion may not actually be obtained on •decomposition, owing to greater or less deterioration and loss through atmos- pheric influences. One pound of fresh chlorinated lime, however, on being treated with sufficient acid for its complete decomposition, may be expected -to evolve about 2.8 cubic feet of chlorine gas. Chlorine is an efficient deodorant through its great affinity for hydro- gen, readUy decomposing hydrogen sulphide, ammonia and volatile aromatic bodies ; the resulting hydrochloric acid further neutralizing a certain amount ■of ammonia. Chlorine is also able to decompose water, particularly in the presence of sunlight, by uniting with the hydrogen and liberating the oxy- gen ; which latter substance, in its turn, attacks and decomposes such organic matter as may be within reach of its action. Chlorine does not readily combine with hydrogen in the dark, but when exposed to light these ele- ments unite with a rapidity proportionate to the intensity of the actinic rays in the light employed. Exposed to ordinary diffuse light, the chemi- cal combination is slow — a fact of practical importance in the considera- tion of the disinfection of such dark places as sewers, cesspools or privy vaults. At the present time, when employed at all, free chlorine is used rather as a deodorant than a disinfectant. Its germicidal action appears to be uncertain and to depend in large degree upon the amount of moisture pres- ent in the atmosphere. Through its high specific gravity, 2.47, chlorine has a constant tendency to seek the lowest level — and hence anything like its equal diffusion, in the disinfection of a large room, can scarcely be ob- tained. The gas has little powers of penetration, and its use, if any, must be practically confined to surface disinfection. In order effectively to utilize chlorine for room disinfection, the proportion of the gas in the at- mosphere must be carried to a degree which wiU result in the extensive bleaching of colored fabrics — a serious hindrance to its practical employ- ment in the military service. Sternberg found that an exposure of six hours to a constant strength of one-half of one per cent, of chlorine was necessary to destroy the potency of vaccine virus. According to Notter and Firth, a proportion of 0.5 per cent, is fatal to all micro-organisms in five to eight hours, while 0.3 per cent, destroys bacterial life in the presence of moisture. A rapid and con- siderable diminution in the percentage of the gas originally present must DISINFECTION. -787 always be anticipated through unavoidable loss by diff'usiorf^ and in its ap- plication to room disinfection a strength of one per cent, of chlorine must be considered as the minimum. For the proper disinfection of a tight chamber of a thousand cubic feet capacity, the decomposition of about foru' pounds of good bleaching powder by about one pound of strong sul- phuric acid would therefore be required. For practical purposes of disin- fection, free chlorine is much inferior to sulphur dioxide; since it is more difficult to control, more dangerous to manipulate and more destructive in its effects. Sulphur Dioxide. — SO,. Through the ease with which it can be generated, as well as its comparatively slight cost, sulphur dioxide is a favorite agent for purposes of disinfection. Possessing powerful reducing properties, its action is directly opposite to that of chlorine ; it having an af&nity for oxygen while chlorine eagerly unites with hydrogen. Siilphur dioxide gas is very irritant to the mucous membranes, and, while it has no such marked toxic action as chlorine, due caution should always be observed in its employment. It condenses to a clear liquid at 18° C. (the tempera- ture of a mixture of ice and salt) even at the ordinary pressure of the atmosphere. It is a heavy gas, having a specific gravity of 2.21, and this property, by preventing its ready diffusion in the atmosphere, operates to some extent against its efficiency as a disinfectant. As ordinarily carried out in practice, sulphur dioxide, for purposes of disinfection, is obtained by combustion of the element sulphur in the at- mosphere. The sulphur to be burned should be carefully calculated in amount according to the size of the room to be disinfected, and should be reduced to. small fragments to favor its more ready and complete combus- tion. For a similar reason the necessary amount of sulphur should be divided into several portions located in different parts of the room, rather .than placed in large quantity in a single utensil. From the high specific gravity of the gas, the sulphur to be burned should be elevated some little .distance above the floor rather than placed upon it. For its combustion, large iron pots serve an excellent purpose and are always available. These pots, containing the necessary amount of sulphur, should be placed on bricks in a tub of water in order to lessen the dangers of accidental con- flagration. The contents may be ignited by Mve coals or shavings — -but better by the free use of alcohol. The operator should at once retire to avoid the irritant fumes which are rapidly generated, the door is tightly closed and all crevices are quickly sealed. For safety as well as rapidity, it is well to employ two men in the work. The room should remain closed for twenty-four to thirty-six hours, after which the windows should be thrown open, from the outside if possible, and the apartment thoroughly aired for some hours. Sulphur dioxide is very soluble in water, the latter taking up nearly forty-five times its bulk of gas, and hence it more readily attacks micro-organisms in a moistened and less resistant state. To assist its action the atmosphere should be impregnated with watery vapor; and this may be produced, without additional diminution of the available oxy- gen in the room, by vaporization of the water surrounding the pot in which the sulphur was placed, through the heat generated by the combus- tion of the sulphur itself. About one-half poimd of water should be vaporized for each pound of 788- THEORY AND PRACTICE OF MILITARY HYGIENE. sulphur burned, to allow for unavoidable defects or losses ; although theo- retically only one-fifth pound of water should be volatilized, for each pound of sulphur burned, in the conversion iato sulphurous acid of the sulphur dioxide produced. This matter of a sufficiency of water vapor is essential to the success of the operation of disinfection; Greddings having found that an exposure of forty-eight hours to a 9.2 per cent, strength of dry sulphur dioxide was unable to destroy various pathogenic bacteria, while micro-organisms under the same conditions were uniformly killed by as low a strength as 1.6 per cent, with an exposure of eighteen hours, when an abimdance of watery vapor was provided. A previous elevation of the temperature of the room, particularly in cold weather, will greatly assist the germicidal action of the sulphur dixoide. Prior to a general disinfection by sulphur dioxide, such metallic ob- jects as are readily attacked . by this body should be removed from its in- tended sphere of iufluence. It is of the greatest importance hermetically to seal all openings from the outside, pasting over with paper all cracks or apertures in walls, windows and doors and stuffing chimneys with news- papers ; since in many instances where this precaution has not been taken the gas so rapidly escapes and its proportion diminishes to such a degree as to destroy its germicidal efficiency. Thus Wolffhiigel foimd that the air of a chamber which at the beginning contained 18 per cent, of sulphur dioxide, by volume, contained only about 4 per cent, at the end of an hour and but 1.8 per cent, at the end of three hours. The experiments of Sternberg on vaccine lymph would seem to show that, in order to be effectively germicidal, sulphur dioxide should be pres- ent in the atmosphere in at least the proportion of 1.4 per cent. Accord- ing to Wernich, if the proportion of sulphurous acid reaches 4 per cent, it becomes an efficient germicide; while Marty placed the minimum at 4.7 per cent. According to Thoinet, an exposure of twenty-four hours to a strength of 4 per cent, invariably destroyed the germs of tuberculosis, cholera, glanders, typhoid fever and diphtheria, provided the chamber did not permit of the escape of the gas; but the micro-organism of anthrax was resistant under those conditions. Wolffhiigel was able to destroy anthrax spores by exposure for twenty-four hours to a 4.5 per cent, strength, working under laboratory conditions implying an air-tight apart- ment and an atmosphere saturated with moisture ; but he concluded that under the conditions found in actual practice sulphm-ous acid must always be considered as a somewhat uncertain disinfectant — an opinion shared by Cassedebat. In view of the many factors which may exert a powerful in- fluence in impairing the germicidal powers of sulphurous acid, it is well to err upon the safe side, if at all, in determining the working minimum for all conditions. From this standpoint the requirement of a fom: per cent, strength, by volume, will not seem excessive. One pound of sulphur, when completely burned in the atmosphere, evolves 11.2 cubic feet of sulphur dioxide. A four per cent, strength of sulphur dioxide, by volume, may be obtained by the complete combustion of not less than fom pounds and two ounces of sulphur to each one thou- sand cubic feet of air space in an absolutely air-tight compartment, and this should be the amount of sulphur employed. A greater proportion of the gas, such as the six, or even ten per cent, strength commonly used in DISINFECTION. 789 ship disinfection by the Marine Hospital service, can be obtaiaed only by means of a special furnace or by the employment of liquefied sulphur- dioxide gas. A recent and eminently satisfactory method for the generation of sul- phur dioxide for purposes of disinfection consists in its evolution from the liquid state, in which, as supplied in tins, siphons and carboys, it is a com- mon article of commerce. In the use of the liquefied sulphur dioxide the danger of accidental fire is avoided, the substance is readily handled and a much greater amount of the gas can be thrown into the atmosphere in a short space of time ; thus avoiding the constant escape of gas by diffusion through the long period of its production, as effected by the ordinary com- bustion of sulphur. To offset the advantage of this method, however, it should be borne in mind, having reference to the atomic weights of sulphur and oxygen, that one poimd of sulphur wiU produce two pounds of sulphur dioxide by its combustion. It is evident, therefore, reversing the proposition, that two pounds of liquefied sulphur dioxide must be used in lieu of each pound of sulphur required — the claims of the manufacturers to the contrary. The method of utilization of the liquefied gas is extremely simple. If the sub- Fia. 363.— Commeroiai Tin of Liquefied Sulphur Dioxide. stance is used in the small tins, it is only necessary to cut simultaneously the leaden pipes in the tops of the necessary number of cans and invert the latter in an ordinary wash-bowl or iron pot, when volatilization rapidly occurs. If the substance be contained in glass or metallic siphons, the room can first be sealed and then the necessary amoimt of liquid sulphur dioxide projected from the outside through a small pipe, passed through the keyhole or other small aperture, into a suitable receptacle. For this purpose, the internal pressure in the siphon is sufficient. The increased expense attached to the use of liquefied sulphur dioxide has been some- thing of a drawback to its general employment — the disinfection per thou- sand cubic feet by its use costing eighty-five to ninety cents, where the solid sulphur necessary for the same space, together with the alcohol used in its ignition, would cost only about one-tenth of that amount. Its convenience, safety and especially the fact that by this method any pro- portion of the gas can quickly and readily be obtained in a given space, should, however, outweigh any minor questions of expense. It has re- cently been prescribed for use in the British army in lieu of roU sulphur. Sulphur fumes of relatively weak strength possess but slight powers of penetration. In the proportion usually obtained by the ordinary method of the combustion of sulphur, too great reliance must not be placed upon simple fumigation with sulphur dioxide in the absence of other and acces- sory measures of disinfection. To be thoroughly ef&cacious, prolonged ex- posure to a considerable proportion of the gas, in the presence of moisture, 790 THEORY AND PRACTICE OF MILITARY HYGIENE. is required. The destructive properties of this substance as regards fabrics may often furnish a strong argument agaiast its use. Formaldehyde.— CHjO. This is a colorless gas, extremely irritat- ing to the mucous membranes and of a strong, pungent odor. It pos- sesses the same specific gravity as air — a fact of great practical importance in regard to its distribution when used as a disinfectant for large spaces. It is somewhat unstable and is of neutral reaction ; although toward alkalies it behaves something like an acid but does not form true salts. At com- mon temperatures it is but slightly soluble in water; but by cooling and agitating, a solution containing forty per cent., by weight, can be made. Its solubility is increased if wood alcohol be added to the water — but in such cases the gas appears to combine with the alcohol and not form a sim- ple solution. According to TriUat, if such an impure solution be heated, the methyl alcohol combines with a certain quantity of formaldehyde in the production of methylal, a body said to possess no germicidal properties whatever. Whenever the gas or its saturated solution is cooled to 20° C. it forms a solid by polymerisation, called paraformaldehyde, through the union of two molecules — and the same body is formed by boiling down a solution of the gas in water. This polymeric product is a white, soapy sub- stance, soluble in water and alcohol. When this latter substance is dried in vacuo, over sulphuric acid, a third body, trioxy methylene, is formed, consisting of three molecules of CH,0. This is a white powder which gives off a strong odor of formaldehyde. Both these polymers are appar- ently restored to the simple gaseous molecule by heating in a current of air ; and are capable of being ignited, burning with a blue flame and leav- ing but little ash. At low temperatures, this polymerization may be to a great extent prevented by the addition of calcium chloride or other neutral substance to the solution of formaldehyde. The addition of formaldehyde to concentrated solutions of the fixed alkalies results in sweet-tasting com- pounds, the nature of which has not as yet been determined. A com- plex amine result^ from its addition to ammonia, and this reaction is util- ized in the quantitative determination of formaldehyde and also as a means of rapidly removing all traces of this irritant gas from recently disinfected rooms. Formaldehyde coagulates albumen, but when added to a solution of serum albumen it prevents it from coagulating by heat. It readily unites with the nitrogenous products of decay, fermentation and decomposition, forming true chemical compounds which are both odorless and sterile. It is thus a true deodorizer; in that it does not mask one odor by another stiU more powerful, but forms new chemical bodies which possess no odor. It is from this property of combining directly with albuminoids forming the protoplasm of micro-organisms that the gas is supposed to derive its powers as a germicide. When formaldehyde solution is boUed with an alkaline solution of re- sorcin the liquid turns red. For the determination of the amount of formaldehyde in a solution De Schweinitz recommends a method depending upon the decomposition of hydroxy lamine. hydrochloride by formaldehyde in the production of hydrochloric acid, the quantity of which may be readily determined by titration with tenth-normal alkali solution. An amplification of this method is adapted to the determination of the quan- DISINFECTION. 791 tity of formaldehyde present at any one time in the air of a space under- going disinfection. Although there are several methods for its production, formaldehyde gas is probably best prepared by bringing the vapor of methylic alcohol, properly mixed with air, into contact with a metallic surface or fine metal- lic powder, or any fine powder which does not melt and upon which neither the air nor alcohol exerts any chemical action. The surface or pow- ders must first be heated to a red heat — ^which temperature chemical imion wiU afterward maintaia. The chemical change involved depends upon the following reaction: CH,0 + = CH^O + H,0. The metals or pow- ders most employed are platinum, copper, copper and iron oxides and coke ; the first-named probably being the best for this purpose. While theoreti- cally about ninety-three per cent., by weight, of the alcohol should become formaldehyde, it is stated that the actual yield will not be over fifteen to twenty per cent, imder ordinary conditions ; the alcohol not usually being more than eighty per cent, pure and a large proportion of it being con- verted into CO, and other organic bodies during generation of the formal- dehyde. Upon silk, woolen and cotton fibers, or upon any coloring agent outside of some of the little used aniUne dyes, formaldehyde has no injuri- ous effect. The dry gas has but slight action on polished metal, but its watery solution rapidly attacks and corrodes steel. The gas may be con- sidered as being comparatively non-toxic to the higher forms of life and considerable quantities may be respired for a short time without iH effects. Still, it is well to observe a certain degree of caution in its use. Formaldehyde in aqueous solution is on the market under various trade names, such as "formalin," "formal " and "woodine " — the latter con- taining an admixture of a considerable quantity of wood alcohol, which some manufacturers add to increase stability. The solid polymer is com- mercially known as " paraf orm " and is probably present to some degree in all formaldehyde solntiona^ According to Stahl, the relative antiseptic value of formaldehyde, as compared with some of the commoner substances used as disinfectants,' is as follows: Hydrogen, peroxide, 1-20,000; mercuric chloride, 1-14,300; silver nitrate, 1-12,500; carbolic acid, 1-333; potassium permanganate, 1-285; boracic acid, 1-143; formaldehyde gas in solution, 1-25,000. The germicidal effect of formaldehyde in watery solution is thus compared by Park and Guerard : Disinfectant. Mercuric chloride Mercuric chloride Silver nitrate Silver nitrate Carbolic acid Carbolic acid Tricresol Tricresol Lysol Lysol • • Formaldehyde (40 percent, sol.) Formaldehyde (40 per cent, sol.) Formaldehyde (40 per cent, sol.) Strength. Bacteria. Destruction of vitality. 1-1,000 1-5,000 1-10,000 1-4,000 3-100 1-300 1-100 1-500 1-100 '1-100 3-100 1-100 1-100 Anthrax spores . . All other germs . Anthrax spores . . All other germs . Anthrax spores . . All other germs . Anthrax spores . . All other germs . Anthrax spores . . All other germs . Anthrax spores . . All other germs . Most other germs. In 5 In 15 In 48 In 2 In 48 In 2 In 48 In 2 In 1 In 5 In 15 In 1 In 30 minutes. minutes. hours. hours. hours, hours. hours. hours. hour. minutes. minutes. hour. minutes. 792 THEOEY AND PRACTICE OE MILITARY HYGIENE. According to Walter, a watery solution of one per cent, strength rapidly destroys all pathogenic micro-organisms; a somewhat longer time being necessary in the case 'of the spore-forming bacteria. Faeces are deodorized almost immediately — and are sterile at the end of ten minutes — ^when mixed with a solution of this strength. Formaldehyde does not appear to be surpassed as a germicide and anti- septic by any other substance unless it be bichloride of mercury, while it possesses the invaluable advantages of not being retarded in action by al- buminoid matter, of not injuring the articles to which it may be applied and of being safer for general use. It cannot be too strongly emphasized that the efficiency of formalde- hyde disinfection largely depends upon its intelligent supervision. The unsatisfactory results obtained by some observers appear to have depended upon different types of apparatus used, the temperature of the room, cur- rents of air and many other factors. Hence conclusions based upon one type of apparatus should not be applied to other methods. The manner of applying the gas also appears largely to influence its efficiency, and better re- sults appear to follow the liberation of a large amount in a short time than the generation of the same quantity in a longer period. A low temperature largely impairs the effectiveness of formaldehyde disinfection and the latter should not be attempted in a temperature below 10° C. Where possible, the room to be sterilized should be artificially heated during cold weather ; as the germicidal action of the gas is more rapid and complete above 27° C. — ^the range between 10° C. and 27° C. appearing to make little difference with its action. A certain amount of moisture in the atmosphere is desir- able, as it tends to retard repolymeriaation. In working with a gaseous disiafectant of this kind the currents of air must also be taken into account. On windy days, in rooms upon the exposed side of a building, the gas escapes so rapidly in spite of due care in sealing air-cracks that it is extremely difficult to obtain thorough disinfection ; and, on account of air-currents, there are small spaces in nearly every room which are extremely difficult to steri- lize. This gas being much more diffusible than sulphur dioxide, propor- tionately greater care is required in sealing up all cracks and crevices in room disinfection. Formaldehyde appears to be an excellent and valuable surface disinfect- ant, but to possess only small penetrative powers under ordinary condi- tions. Park states that three times the ordinary quantity must be used to penetrate a single thickness of cloth ; whence it follows that heavy fabrics should preferably be disinfected by steam, boiling or soaking in germicidal solution. It appears to be established that an exposure of not less than eight hours, at a temperature not lower than 10° C. and to a strength of formaldehyde gas not less than one per cent, by volume, will effect surface sterilisation. Positive results may be obtained with similar amounts and shorter exposure, but they cannot be regarded as uniform under all cir- cumstances. It should be understood that proportion of gas and time of exposure cannot well be separated. The time of exposure must vary as the amount — ^but it is a safe plan in practice to make the amount large and the time long. According to Fournier, the combination of acetone with formaldehyde greatly increases the penetrating power of the latter. The acetone has no bactericidal effect but merely serves as a mechanical DISINFECTION. 793 vehicle for the formaldehyde. He advises the preliininary treatment of the room with the vapor of a mixture of acetone and water, equal parts, followed after an interval of an hour by the use of the formaldehyde. For the rapid generation of formaldehyde gas, outside the use of the spray already described, some special apparatus is required. As before noted, it may be slowly evolved by spontaneous evaporation from its watery solu- tion ; but any attempt to expel the gas more rapidly by boiling appears to result largely in the production of a polymer, which requires for fts decom- position a heat considerably above that of boiling water. The generation of the gas in its direct production from methyl alcohol depends upon re- tarded combustion, and hence the ignition or the use of too great heat in the use of the alcohol simply results in the splitting up of that substance into elementary bodies without the production of formaldehyde. Since the solid paraform resolves into the original formic aldehyde at 135° C, it is evident that the application of too great heat may result in the complete IST Fig. 363.— Bowdoln Apparatus for the Generation of Formaldehyde from Wood Alcohol. combustion of paraform pastUs without the evolution of formaldehyde in any considerable amount. To meet the above conditions three types of apparatus, intended for the generation or Kberation of the gas from wood alcohol, from a watery solution of the gas and from its solid polymer, are now on the market. A number of modifications of these original types have been constructed, but these do not differ essentially from each other. One general fault appears to be that the generators are too small, and hence too slow in action, to give full satisfaction in the disinfection of large rooms. On account of the great diffusibUity of the gas, the best apparatus for room disinfection is that which can be relied upon to liberate the greatest amount of the gas in the least time and which combines simplicity with durability and cheap- ness. The main idea is to get the necessary proportion of gas into the room in the shortest possible period. Hence, in the sterUization of large spaces, it is well, if the type of apparatus be small, to operate several generators simultaneously. The simplest apparatus in which wood alcohol is directly converted into formaldehyde is that known as the Bowdoin generator. In this ap- paratus the fumes of wood alcohol contained in a receiver are passed through a coUar of hot platinized asbestos. In the operation, the alcohol in the re- ceiver is ignited and the asbestos collar held over the flame until incan- descent, usually requiring about half a minute, and is then dropped over the 794 THEORY AND PRACTICE OP MILITARY HYGIENE. receiver, smothering the flame. The heat abeady created, however, con- tinues to volatilize the wood spirit, which, passing through the asbestos, maiatauis its incandescence and is itself decomposed into formaldehyde — the opera- tion continuing automatically until the sup- ply of alcohol is completely exhausted. This apparatus does not yield by any means the amount of formaldehyde gas theoretically possible ; the loss probably being due to the great difficulty of maintaining the asbestos at a constant temperature. As a result, a considerable portion of the alcohol suffers complete combustion in the production of bodies of no germicidal value. The appara- tus described is both cheap and simple, but has necessarily to be abandoned in the room to be disinfected. Careful investigation has shown that by its use about fifteen per cent., by weight, of the alcohol used wUl be converted into formaldehyde; hence requiring as a minimum 500 cubic centi- meters of wood spirit for each 1,000 cubic feet of space to be disinfected. The Ma- rine Hospital service requires the use of 750 cubic centimeters for each 1,000 cubic feet and the employment of a generator capable of converting one liter of wood al- cohol into formaldehyde per hour. The cost of operating this form of apparatus, on account of wastage, is somewhat in excess of those using formaldehyde in watery solution or the solid paraform. With this method, the amount of ammonia required for neutralizing the formal- dehyde after the completion of disinfection can be evolved by heating or spraying one part of water of ammonia for each part of wood alcohol used. Of the appliances for expelling formaldehyde from its watery solution, the TrOlat autoclave is the original type from which a number of modifica- tions have emanated. In the use of formaldehyde in solution, known under the various trade names of " for- malin," " f ormochloral " and "formal," it is necessary to bring such solution to a minimum temperature of 135° C. to prevent repolymerization. Hence the em- ployment of the autoclave, in which it is readily pos- sible to create an internal pressm-e of three or four atmospheres before permitting the outflow of any of the gas. This apparatus also has the practical advantage of causing the sudden influx of a large quantity of gas into the apartment to be disinfected, and as the formaldehyde may be readily conducted through a no. sas.— severing and tube wherever wanted and the apparatus manipulated Generanon^ot Format outside the room, the latter is consequently always pSorm™"" *"" ^""'^ Fig. 364.— Kny-Scheerer Apparatus, the Liberation ol Formaiaeliyae from its Watery Solution. DISINFECTION. 795 under the supervision of the operator. An improved form of Trillat's gen- erator is that of the Kny-Scheerer Company, at present supplied in the United States army, which appears to possess all the qualities for room disinfection ; being simple in construction, safe in operation and requiring no great original outlay. Struever has shown that only about seventy-eight per cent, of a forty per cent, solution of formaldehyde can be actually ob- tained for disinfection purposes. . Since allowance for the gas escaping from the room must also be made, it wOl scarcely be safe to use with this appa- ratus less than 350 cubic centimeters of formalin per 1,000 cubic feet; the cost of disinfection with this apparatus being about eleven cents per thou- sand feet. For neutralization of any remaining formaldehyde after the use Fig. 366.— FormaldehydeCliamber, for the DMnlection of Small Articles. of this method, 1.25 liters of water of ammonia should be employed for each liter of formalin used. For the vaporization of the solid paraformaldehyde, compressed into pastils, the Schering and Glatz lamp has been constructed. The operation of the apparatus is simple, and consists merely in the application of heat to the necessary number of pastils when placed in the cup of the disinfector. This method of generation is cleanly and convenient, but is somewhat more expensive than the preceding. At present the lamps on the market are small and scarcely adapted to the disinfection of large spaces, but are ad- mirable for the sterilization of instruments and similar articles. Care must be taken not to apply too great heat to the paraform pastils, since otherwise these decompose in the production of bodies other than formaldehyde. The cost of sterilization with this lamp is about twenty cents per thousand feet.; For success with the use of this solid isomer not less than one gram should be volatilized for each twenty cubic feet of space. To neutralize completely 796 THEORY AND PRACTICE OF MILITARY HYGIENE. the resulting formaldehyde, one liter of water of ammonia for each 150 grams of the solid used must be employed. For the disinfection of articles which are too valuable to be destroyed by fire and which cannot be rendered germ-free by other means without injury, certain special chambers for disinfection with formaldehyde have been designed. In such chambers, with the high proportion of the gas which can be secured, penetration to a satisfactory degree can be obtained with bulky articles. The previous creation of a partial vacuum of course materially assists the penetration of the formaldehyde. The objection to a small chamber, if the gas be expelled from its watery solution, is that moist- ure from the evaporation of the water collects on the inside of the chamber and wets the goods where they come in contact with the walls. The gas should hence be preferably applied in the dry state in a strength of not less than twenty per cent, by volume, and the time of exposiu-e should not be less than one hour. In the absence of any specially constructed chamber, and particularly ior use in the field, an excellent disinfection chamber may be made from Fig. 367.— Improvised Dlsinlecting Bag with Formaldehyde Generator, for Field Use. a large box the seams of which have been tightly caulked ; or by the use of a large canvas sack the exterior of which has received several coats of white lead. The operation of this arrangement is shown in the accom- paying illustration. Formaldehyde gas is superior to sulphur dioxide as a disinfectant for dwellings because it is more efficient and rapid in its action ; because it is less injurious in its effects on household goods; because it is less toxic to the higher forms of animal life ; because, when supplied from a generator placed outside of the room and watched by an attendant, there is less danger of fire. Apart from the cost of the apparatus and the greater time involved, formaldehyde gas, generated from commercial formalin, is not more expen- sive than sulphur dioxide, viz. : eight to ten cents per thousand cubic feet l)eing approximately the cost of the disinfectant in either case. Special Applications of the Disinfective Processes. Room Disinfection. — In the disinfection of habitations, the processes are not as yet perfected nor do the problems presented always appear easy of solution. The disinfection of a closed space is a complex operation, im- plying not only contact with germicidal substances in gaseous form but also mechanical cleansing and the application of disinfectant solution. Hence, on the account of the necessity of evacuation by the occupants and the arduous nature of the processes of disipfection as applied to habitations, DISINFECTION. 797 the employment of the latter should usually not be advised in the absence of ample justification for such action. In the routine method for the disinfection of a room the sealing up of all its openings and its fumigation should precede all other treatment. When properly carried out, a large proportion of the infectious germs, even if not all, are destroyed by this process ; rendering their dissemination in the subsequent steps of the operation less liable to occur, as also the con- traction of disease by the persons engaged in the work of disinfection. The gaseous agent selected should if possible be either sulplmr dioxide or formaldehyde — and of these, preferably the latter. After sealing up all cracks from the outside, and the preparation of the room and its contents in the manner best calculated to assist the germicidal action of the gas, the operation of fumigation is carried out in the manner aheady described. UsuEilly the formaldehyde generator is placed just outside the door and the gas pa'^sed into the room through the keyhole. After sufficient exposure to the gas, the room is thrown open and thoroughly aired, small articles as clothing, fabrics or furniture being removed for such fin-ther treatment for their dis- infection as may be appropriate. If formaldehyde is used, any excess of gas in the room may be neutralized by ammonia sprayed through the key- hole before entrance. The nature of the wall determines the method to be employed for its disinfection. If painted in oil a simple washing or spraying with a disin- fectant solution, in connection with fumigation, will give satisfactory re- sults. Wainscoting should receive the same treatment as flooring. Papered walls should have all layers of paper removed, be washed or sprayed with a germicidal solution, preferably a five or ten per cent, filtered solution of chlorinated lime, and then be re-papered. Calcimined or white- washed walls should be cleansed, washed with a solution of chlorinated lime and thoroughly re-calcimined or whitewashed. An excellent method for the mechanical cleansing of walls consists in the employment of pieces of stale bread, into which the adherent dirt and bacteria are incorporated by rubbing. After the operation, all crumbs and fragments of the bread are carefully collected and burned. While excellent results are attained by this method, as well as by the use of cloths wet in disin- fectant solutions, properly to rub down the walls of a large room requires the expenditure of much time and labor. For the disinfection of walls the removal of plaster is not necessary ; but barrack and hospital walls should always be impermeable to moisture to facihtate their disinfection. Bacterial life is naturally much more abundant on the lower than the higher portion of walls; thus the niunber of germs present near the floor of a stall examined by Duclaux was ten times greater than at an elevation of one meter. It is quite often considered that the ceUing is not infected, since it is evidently so much less exposed to contamination than the floors and lower portion of the walls. StiH, a certain amount of dust and par- ticulate matter is always adherent to the ceUing and hence the latter should receive its share of attention in the process of disinfection. Woodwork, such as doors and window-frames, should be cleansed with soap and hot water, washed with a solution of bichloride of mercury and repainted when dry. After any debris present has been dampened and care- fully removed, the floor should be cleansed with soapsuds or strong lye and 798 THEOEY AND PEACTICE OF MILITARY HYGIENE. then thoroughly scrubbed with a standard solution of mercuric chloride or tricresol, particular attention being given to the treatment of all joints or cracks. For this piu-pose an unnecessary amount of fluid should not be employed, since the germicidal properties of the agents used are soon de- stroyed — the coal-tar products by evaporation and mercuric chloride through its affinity for organic matter — and the remaining moisture favors subse- quent bacterial development. Disinfection of ordinary floors is not always a simple matter owing to the number of crevices, filled with organic matter and detritus, which afford protection to micro-organisms and offer a favor- able medium for their development. For this reason, wooden flooriug should always be made of carefully matched and seasoned material and should then be rendered impervious by one of the methods described in a pre- vious chapter. Floors so prepared are readily disinfected by simply mop- ping with some suitable solution. Stone or tQe floors are disinfected in the manner above described. If stone floors are in bad condition, after the removal of all dirt from cracks and crevices and their careful disinfection, it is desirable that a solid new flooring of cement, asphalt or concrete should be superimposed. Dead spaces between floors, if tight, are preferably disinfected by the use of formaldehyde gas, generated in the autoclave apparatus. If open to the air and infection appears probable, a few floor boards may be re- moved and the interior washed or sprayed with a filtered solution of chlori- nated lime of ten per cent, strength. Exposure of the room to the action of the sunlight and to free perfla- tion by the air, for several days following the completion of the processes of disinfection, is always desirable. Disinfection of Stables. — Prior to the application of the processes of disinfection to the structure itself, all small articles are to be removed; such as have possibly undergone contamination, particularly buckets, curry- combs, brushes and such horse equipment as may have come in con- tact with sick animals or with infectious material, should be promptly sterilized. Metallic objects or utensils, after a thorough preliminary cleansing with soap, a stiff brush and hot water, may be sterilized by boil- ing or else by being immersed or washed in a five per cent, solution of car- bolic acid or a two per cent, solution of tricresol. Leather articles, as har- ness or equipment, should receive a similar preliminary cleansing and either be scrubbed with a solution of bichloride of mercury 1-1,000 strength, a strong solution of carbolic acid or tricresol, or be subjected to the continued action of formaldehyde gas. Blankets and horse-covers may be disinfected by soaking for several hours in a strong solution of mercuric chloride 1-800, renewed according to necessity. They should then be dried in the open air and, if possible, subsequently washed. For the disinfection of the stable itself, all hay and grain should be removed from racks and mangers and all bedding from the floors. After its careful collection at some designated point, this refuse should be satu- rated with mineral oil and destroyed by fire. All interstices in the floor and walls should be scraped out and the debris removed, carefully swept up and burned. The woodwork should be cleansed throughout with hot lye or strong soft-soap solution, following which all mangers, hay-racks, stall partitions, floors and walls are to be thoroughly scrubbed with a one per DISINFECTION. 799 cent, solution of tricresol applied vigorously with the aid of a stiff brush ; care being taken that all parts of any cracks or crevices are penetrated. After several days' exposure to air and "sunlight the interior of the stable should receive a coat of whitewash, applied thickly and prepared from lime freshly bmned shortly before the time of use. After the completion of the processes of disinfection, the stable should not be re-occupied for several days to permit of thorough drying, airing and the disinfectant action of the whitewash. Horse troughs used for the watering of animals are, when infected, to be emptied of their contents. If not connected with a drain or sewer, the water should be sterilized by the addition of a proper amount of a suitable disinfectant before being poured upon the ground. Cleanliness of the troughs should be thoroughly accomplished and all organic matter, animal or vegetable, removed and disinfected by fire or by immersion in some strong germicidal solution. For metal-lined troughs the use of acid solutions or bichloride of mercury is of course inapplicable, and such may be disinfected by the use of one of the coal-tar products. Wooden troughs may be treated with an acid solution of mercuric chloride. The operation is completed by a thorough flushing of the trough with a large amount of clean water and by exposure to the sun and air, in a dry condition, for forty-eight hours. All pipes or carriers of the overflow water should be carefully disinfected with five per cent, carbolic acid solution. Disinfection of Wells and Cisterns. — It is not necessary to em- phasize the fact that, where possible, all suspicious water-supplies should be avoided ; but circumstances may arise by which a well, the only readily available source of supply for an isolated military camp or station, may be temporarily infected and seriously inconvenience the users of the water, vmless some safe remedy is at hand. To meet the requirements of such cases, efforts have been made to determine how far it is possible to disin- fect weUs ; with the result that this has been shown to be practicable, providing the contamination has not been great and is not continuous. The method recommended for the disinfection of weUs which have been only temporarily polluted, as by the accidental deposition into them of in- fective matters from above or the washing into them of such material by storm-water, consists in pouring a mixture of equal parts of crude carbolic acid and sulphmic acid into the well until it is present in the proportion of about five per cent, of the total contents. The mixing of the whole should be thorough, and the walls of the well should be scrubbed with brooms dipped in the solution. The inside of the delivery pipe should be thoroughly cleaned by flushing with the solution and scrubbing with a long-handled brush wet with the same disinfectant. After standing for twenty-four hours the contents should be pumped out, the slime from the bottom thoroughly re- moved and the well allowed to refill. This process is repeated until aU traces of the acid have disappeared. Disinfection of weUs is also practised by the use of freshly burned lime. About half a barrel of lime is thrown into the well, stirred up with the water and the walls are scrubbed down with the resulting milk of lime. The weU is then pumped out, cleaned, allowed to refiU and a second sup- ply of Hme added ; after which the well is allowed to stand for twenty- four hours. After a thorough stirring the solution is then pumped out, 800 THEORY AND PEACTICE OF MILITARY HYGIENE. and the well is allowed to refill and is re-emptied untU the water removed is practically free from lime. The delivery pipe is scrubbed with strong carbolic-acid solution. For drinkiug purposes alone, all water that is of necessity derived from suspicious sources should be boiled before use. No process of dis- infection of wells can replace this precaution, and the former is of value chiefly as it removes the danger of indirect and accidental infection from the use of the water for bathing, washing and domestic purposes. Disinfection of Tentage. — As with other habitations, temporary evacuation is an essential preliminary to the disinfection of tentage. After removal of all contained articles for their disinfection by appropriate methods, the tents, while standing, should be sponged or sprayed with a two per cent, solution of tricresol or a four per cent, strength of carbolic acid. The lower portion of the canvas walls, together with the sod-cloth, should receive a particularly thorough wettiug — outside as well as inside. The tent poles should be washed with the same solution and the flooring, if any, taken up and subjected to the same treatment. The site of the tent having been thoroughly policed, it may be well sprinkled with a ten per cent, solution of chloriuated lime ; or calcic oxide may be so scattered over the space as to form a thru layer, the lime being immediately slaked in situ by the use of a spray or watering-pot. Flooring, as well as the interior of the tent, should be exposed to the air and sunlight for several days. The floor should not be laid down until the necessity for such action becomes urgent through the intended early re-occupancy of the tent, when a new location for the latter should be selected. A much more de- sirable method, but one implying infinitely greater labor, consists in the striking of all tents and the sterilization of their canvas by boiling in large improvised vats. After thorough washing of tent poles and floors with tricresol solution, the camp should preferably be established at some im- infected point and the former site abandoned. Disinfection of Clothing. — The processes of disinfection must be carried out with special care when applied to articles of clothing or bed- ding; since such objects, which have been in close contact with the per- sons of the sick, are necessarily particularly dangerous through the greater amount of infectious material with which they are permeated. Clothing, bed-olothing and similar articles, when infected, should be placed in tight receptacles or rolled in sheets wet with some germicidal solution to avoid dissemination of morbific matter during transportation to the place of disinfection; or special sacks might be kept on hand for this purpose, as is the custom in the French army. Such articles should of course be unrolled or removed from the sacks prior to the commencement of the process of disinfection. All articles belonging to the soldier which are made of cotton, such as shirts, stockings or towels, may be sterilized by any of the accepted methods. On account of its comparative simplicity and readiness of ap- plication, immediate immersion in a strong disinfectant solution with sub- sequent boiling and washing best answers aU purposes. In time of epi- demic a suitable water-tight receptacle, containing some strong disinfectant solution, should habitually be kept outside the ward in which infectious cases are receiving treatment. All infected articles should be at once DISINFECTION. 801 submerged in this solution and allowed to remain until their removal to the laundry, where boiling of the articles iu soap-suds or a weak soda solution should be performed before washiag. When soiled by evacuations, secretions or excretions, the method of disinfecting bed or body linen is somewhat different. Infected articles thus contaminated should be iiomersed in a solution made up of three parts of carbolic acid, two parts of ordinary soft soap and one hundred parts of cold water. They should be allowed to soak in this solution for two hours and then be riused out before being subjected to the ordinary laundry processes. * The reason for this immersion in cold carbolized-soap solution is that it not only destroys all non-sporulating bacteria but also dissolves out blood and faecal stains ; the latter being rendered indelible by coagulation of their albuminous constituents, if the soiled articles should be at once exposed to steam, boiling water or corrosive sublimate solution. Articles of woolen material, as uniform blouses, trousers or flannel shirts, should not be disinfected by boiling on account of the resulting shrinkage of the fabric; the use of flowing steam and simple immersion in disinfectant solution not being entirely free from the same objection. Woolen wearing apparel, well spread out, is disinfected with the least deterioration of qual- ity by the use of formaldehyde gas, the employment of which for this purpose has already been outlined. Superheated steam is much employed for this object and gives excellent results. In its use the clothing should be loosely hung up on hooks in the chamber, the temperature raised to 110°- 112° C. and maintained at that point for twenty minutes. In the British service an exposure of one hour to a temperature not less than 105° C. is required. Clothing which has been disinfected by superheated steam should not be allowed to remain in the apparatus, but should be hung in the open air to dry so as to avoid the production of creases. Disinfection of fabrics by means of sulphur dioxide may be satisfactorily employed with all articles which, through their nature, suffer deterioration or injury on exposure to dry or moist heat or on immersion in disinfectant solutions. In selecting a room for such purposes it should be no larger than the prob- able necessities demand, nor should it be in any occupied habitation on account of the discomfort which would otherwise be caused among the inmates. It should have impermeable walls and floors and the windows and doors should be capable of being hermetically sealed. Since the sides of wooden boxes are easily penetrated by sulphur dioxide gas, their use gives unsatisfactory results unless they are well papered on the inside with stout and preferably glazed paper. The articles to be disinfected are hung up in the chamber and are so disposed as to present the greatest amount of surface to the action of the gas. Exposure should last for thirty-six hours, at the end of which time the articles should be thoroughly sunned and aired. For the disinfection of clothing by sulphur dioxide its genera- tion from the liquid state is preferable, and its presence in considerable strength, favors penetration of fabrics. Disinfection by sulphur dioxide is applicable to aU fabrics although, in concentration of four per cent, and particularly in the presence of moisture, it has a tendency to fade colors. This is to some extent the case with the sky-blue kersey uniform trousers. Bed-clothing, when disinfected with sulphur, may long retain an extremely disagreeable odor of hydrogen sulphide. Spraying with a ten per cent. 51 802 THEOEY AND PRACTICE OF MILITARY HYGIENE. strength of formaliii solution gives excellent results if due care and thor- oughness be observed throughout the operation, and the articles are hung up for some hours in a small, tight space. If immersion of woolen fabrics in a disinfectant solution becomes necessary in the absence of better methods of disinfection, the solution employed should not contain a free mineral acid, it should be cold, the garments should be submerged without rubbing and should be allowed to dry in the open air without wringiag or other unnecessary manipulation. Under all circumstances, but particularly in time of epidemics, the sterilization of the personal apparel of the soldier, where required, should be accomplished as promptly as possible. An excellent rule is promptly to disinfect the wearing apparel of aU men who enter hospital for treatment, irrespective of the cause of their entrance. Disinfection of Excreta. — Faecal matter of an infectious character is ordiaarily disinfected by the application of germicidal substances in solution. Vessels intended to receive these matters should contain in ad- vance a sufficient quantity of the solution selected; and, upon receipt of the infectious material, should be sufiEiciently agitated thoroughly to mix the contents, covered and allowed to stand at least one-half hour before being emptied and cleansed. Absolute sterilization is to be obtained only by thorough mixing, a procedure, even with small quantities of faecal mat- ter, which is extremely unpleasant as well as somewhat difficult of accom- plishment. With large amounts of faeces, attempts at disinfection will in practice generally give results which in their nature are partial rather than absolute. The best disinfectants for faecal matters are such as possess, in addi- tion to cheapness and strong germicidal qualities, the property of destroy- ing bad odors. It is better that such chemical change be induced as will actually destroy odors of this character rather than mask one bad smell by another still more powerful. For the destruction of faecal efflu-via a strong solution of the sulphate of iron, though possessing but comparatively feeble germicidal powers, best answers aU indications. The use of chlorinated lime serves an excellent purpose, except for the disagreeable odor possessed by this substance itself. It is well to remember, in this connection, that foul odors are always to be prevented by the maintenance of strict cleanli- ness, and that their existence necessarily implies an absence or an incom- plete execution of those sanitary provisions by which the highest condition of health can only be maintained. Dry earth possesses no antiseptic qualities and merely promotes the desiccation and decomposition of excrement while absorbing the odor. Corrosive sublimate solution of 1-1,000 strength, when mixed with equal parts of faeces, neither destroys the odor nor accomplishes disinfection, while a five per cent, solution of carbolic acid, added to a similar bulk of faeces, does not render the latter sterile at the end of an hour. Tricresol, however, is a valuable agent for this purpose, since its activity is not impaired by the presence of albuminous matter. In a strength of one per cent, this sub- stance is something of a deodorant as well as actively germicidal. For the destruction of the typhoid bacillus a mixture of copper sulphate and sulphuric acid, each in two per cent, strength, is said to be particularly efficacious. DISINFECTION. 803 From determinations made by Viacent, the efficiency of the various dis- infectants officially provided for use in the army of the United States, as regards the sterilization and deodorization of fresh or decomposing faecal matter, would seem to be as follows : Chlorinated lime Lime (calcium oxide) Labarraque's solution Carbolic acid Bichloride of mercury, 1-1,000 acid solution Sulphate of iron Deodorizing power. Very good. Fair Good Good Poor Very good Quantity of Disinfectant Required. For the dlslnIeoHon 1,000 c.c. of faBcal matter In twenty- four hours. 10-16 gm . 100 gm. 250 gm. 30 gm More than 300 c.c . More than 200 gm . For each man dally, when considered aa the unit of a large body In the Held. 17-28.3 gm. 35 gm. More than 850 c.c. More than 340 gm. For the disinfection of small quantities of faeces the use of a solution of tricresol, two per cent, strength, would seem to be most applicable. For the disinfection of latrines the employment of chlorinated lime or freshly burned lime (calcic oxide), with the use of sulphate of iron when required, is advisable on the ground of cheapness, germicidal efficiency and deodorizing properties. In permanent barracks with water carriage and modern plumbing an attempt at the disinfection of the discharges is imnecessary, except during epidemics. When this appears to be advisable, the water-closets should be thoroughly scrubbed with a five per cent, carbolic acid or a two per cent, tricresol or chlorinated lime solution. Sufficient of the solution should be passed into them to fill the traps completely, and leave a quantity of the disinfectant in the body of the fixture. Care should be taken after con- cluding this procedure that no infected discharges again find thek way into the closets, but aU discharges of this nature should be carefuUy sterilized before being thrown down the hoppers. The disinfection of urinals is accomplished by the same means as is that of water-closets, except that milk of lime should not be used for this purpose. For the disinfection of infected faeces and urine, these should be passed directly into a five per cent, solution of carboKc acid or a two per cent, solution of tricresol. When milk of lime is used, the excreta should be mixed with a double volume of this material. Whatever the disinfectant solution used, care should be taken that this and the faecal matter are well mixed and the whole should be covered up and allowed to stand for half an hour to one hour. The mixture may then be diluted with hot water and poured slowly into the water-closet — the flush of which should be allowed to run at the same time to prevent clogging of the trap. The disinfection of privy pits and latrine trenches may often be re- quired. While the first should not be tolerated at a military post, they may be best and most satisfactorily disinfected by the use of milk of lime, made up in the proportion of at least two per cent, of the contents of the vault; or it should be added and thoroughly mixed until the entire mass is strongly alkaline to litmus paper. By beginning with an empty and 804 THEOEY AND PRACTICE OF MILITARY HYGIENE. clean privy-vault and adding the lime mixture daily, not only is the odor prevented but the mass is continuously disinfected. Sulphate of iron is very ef&cient in destroying bad odors generated under such conditions. For the disinfection of latrine trenches the above methods may be employed ; but, as already mentioned, an excellent means of accomplishing disinfec- tion xmder field conditions consists in a daily burning out of the trenches by the combustion of leaves, straw, dry grass or manure, scattered over the contents and sprinkled with petroleum. The ideal ultimate disposition of infectious faecal matter is by crema- tion in special apparatus. Unfortunately this method of disposal is usu- ally not practicable except on a small scale ; and even then implies the outlay of considerable additional effort and expense. Its use, however, in connection with the administration of hospitals in the field should always be resorted to, particularly in time of epidemic; the exercise of a lit- tle ingenuity readily permitting the construction of forms of apparatus which, though crude ia detail, may give eminently satisfactory results in operation. These have been discussed to some extent in a previous chapter. The sputum of cases of tuberculosis and diphtheria, and probably also that of pneumonia, is an important agent iu the propagation of disease from the infected individual. Such sputum, particularly when of a tuber- culous nature, is much more dangerous when dried than when in the moist condition; hence the great object is to maintain the sputum in the latter state until the time of its destruction. For this purpose cuspidors should be freely distributed throughout the barracks. They should, while iu use, receive a daily disinfection and cleansing and should at all times contain a sufficient quantity of germicidal solution. The use in cuspidors of solu- tions of carbolic acid and mercuric chloride is not, however, of advantage, since both coagulate mucus and the former, in addition, possesses an un- pleasant odor. Probably the use of fresh milk of lime is best for this purpose. Sputum is best disinfected by the application of moist heat. Boiling water almost instantaneously destroys the tubercle bacillus while in the wet condition, but exposure to its action for a much longer period is required for its destruction after desiccation. In ordinary practice, cus- pidors may best be sterilized by immersion in boiling water for a period of ten minutes. Sputum which has become hardened and adherent to the receptacle through drying may be loosened by the use of a solution of lye or other strong alkali. Miscellaneous. — Articles of wood may be disinfected by washing with a germicidal solution or by exposure to a gaseous disinfectant. Leather cannot be disinfected by steam without imdergoing severe injury, and articles as harness, horse equipment, boots or shoes must hence be disinfected by other measures. A mechanical cleansing preceded by the application of or immersion in some germicidal solution is the method usually employed, but this is probably inferior to disinfection by means of formaldehyde gas. Cooking or eating utensils are preferably disinfected by immersion in boiling water, as are also objects of metalKc nature. Musical wind instruments are best sterilized by boLling, the mouthpiece being removed and receiving special attention. Wooden musical instru- DISINFECTION. 805 ments, which cannot he hoiled, should be taken apart, cleansed and sponged with formalin. Wagons and ambulances may be disinfected by thorough prehminary cleansing with soap and hot water, followed by the application of some suitable germicidal solution by sponge, brush or hand pump. Disinfection of the Person. — Attempts at disiafection of the per- sons of the sick — whether it be by the use of disiafectant ointments in scarlatina, gargles, sprays and mouth washes ia diphtheria or medication calculated to asepticize the faeces and urine in typhoid fever — ^while ia every way praiseworthy, may be considered as entirely lacking in that completeness of action upon which the definition of the term disinfection depends. While such efforts may have considerable inhibitory effect, as regards the vitality, propagation and dissemiaation of the specific germs extruded from the organism, this effect is only temporary, and the most painstaking endeavor fails entirely to reach the systemic foci from which myriads of infectious bacteria are constantly being discharged. Disinfec- tion of the person of the sick will therefore be accomplished only as a result of processes occurring in the individual himself; depending upon his vital resistance and his powers of destruction and elimination, through the formation of antitoxins, as regards an invading and infectious micro- organism. The disinfection of the person of the convalescent within whose organ- ism, through an acquired immunity, the forces of an infectious disease have ceased to act, as well as with regard to the healthy individual, who may be temporarily the vehicle of infectious matter, is, for all practical pur- poses, capable of accomplishment. The process includes the attainment of thorough personal cleanliness through the use of hot water, soap and flesh or nail brush, the shampooing of the hair and beard with borax and the application of a solution of mercuric chloride, 1-3,000, to the entire sur- face of the body — a solution made up of one part of Labarraque's solution to nineteen of water also being excellent for this latter purpose. The Sanitary Officer and His Assistants. — The various processes which go to make up the procedure known as disiafection require, above all things, exactness and attention to small details to ensure ultimate suc- cess. Hence the sanitary officer wiU not relieve himself of the responsibility for such a delicate and important operation if with a few vaguely worded and ill imderstood directions the matter is turned over to enlisted sub- ordinates, who, faulty in their technique, are absolutely ignorant of the scientific principles underlying the processes which they are called upon to perform. The sanitary officer himself should personally superintend and direct the operation of disinfection. He should have careful super- vision over the preparation as well as the employment of the various agents used, should minutely instruct those engaged in the work in the proper performance of their duties and the dangers to which they them- selves may be exposed, and his should be the responsibility for any acci- dents during the operation. He should specifically name aU articles and places to be disinfected and he should make sure that his orders are obeyed in the spirit as well as the letter. As far as possible, all work of disinfection should be done by the men of the Hospital Corps ; although, if considerable rough labor be necessary, a certain portion of it may safely be delegated to such soldiers of the line 806 THEORY AND PRACTICE OF MILITARY HYGIENE. as may be detailed for such duty under the orders and control of the sani- tary department. All individuals engaged in the work of disinfection should wear complete outer clothing of cotton duck which, on ceasiug work, may be removed and sterilized by boUiug, steaming or soaking in disinfectant solution. Under no circumstances should clothing be worn in the constant contact and close relation of the camp and barracks, which has served the soldier for use while engaged in the process of disiufection. At the end of each day, or on concluding the task, the hands, face, hair and beard should be washed and disiafected, a general bath should be taken and clean clothiug donned. Eating and drinkiug, during the continuance of the processes of disiufection, by those who have the operation in charge, is always to be avoided. CHAPTER XVII. THE HABITS OF THE SOLDIER AS AFFECTING HIS EFFICIENCY. AliCOHOIilSM. The attitude of the recruit toward the use of iatoxioatiug liquors is largely deterinuied prior to his entrance into the military service ; but that a few soldiers become drinking men after enlistment, as a result of social environment, in the army as in civil life, cannot be denied. To this end the common practice of " treating "—used as an expression of hospitality or social courtesy, often under circumstances when liquor may not be de- sired by either the recipient or donor — contributes not a Kttle ; and to drink and ask the companionship of others in consuming alcoholic bever- ages is the first step toward the development of the confirmed drunkard. Further, the idea that social superiority attaches to an ability to consume large quantities of alcoholics stUl exists to a certain extent among soldiers of a lower and more depraved class , and by such a novice in the art of drinking may not rarely be assailed with ridicule and contempt. Such men, now fortunately few in our army, are largely responsible for the idea which occasionally obtains among recruits, that a physical toler- ance of alcohol is an essential attribute of the soldier and that only he who is able to imbibe his share of intoxicant without apparent effect has demonstrated his fitness to enter upon the profession of arms. Some few soldiers xmdoubtedly acquire the habit of taking alcoholic stimulants largely as a result of favorable opportunity, particularly if they are men without aim or purpose in life beyond the perfunctory accomplishment of routine duties — men who are possessed of no internal resources for their amusement and to whom the normal existence is burdensome, dull and monotonous. A stiH smaller class of soldiers appears to be markedly in- fluenced by atmospheric conditions, with respect to alcoholics ; and prolonged exposure to heat, cold and moisture have frequently been observed to develop, in such men, a latent desire for drink which probably otherwise would have remained dormant. A certain number of periodical military drunkards are true degenerates. Without apparent cause, in the face of promises and protests to the contrary and in spite of the knowledge of inevitable court-martial and disgrace, alcoholic excesses are begun and continued until exhausted nature brings the debauch to a close. Then follow deep contrition and humiliation, renewed and earnest promises of reform and an apparently sincere attempt to repair the damage done to health and character, a period of decorous life, and again a plunge into excess. The greater proportion of inebriates, however, as found in the military service, appear to be men of unstable mental equilibrium, indeci- sion and weak character. Such, under any conditions out of the ordinary. THEORY AND PEACTICE OF MILITAEY HYGIENE. find the mental strain beyond their power of endurance and promptly seek relief m the nerve -benumbing effects of alcohol. Of recent years, the idea has been advanced that the drunkard is not always responsible for his acts ; that he may be physically and morally de- fective and should be treated not as an offender but as a sick man sub- ject to a species of insanity. This idea, accepted by many as explaiaing and excusing all cases of alcoholism, is highly misleading and is applicable only to a restricted class hi which inebriety is but one of the several out- ward manifestations of an Hi-balanced mentality. It is safe to consider that the tendency toward alcoholism, instead of being a specific disease which drives its victim to some form of narcotic excess, simply expresses a defect in the nervous organization which makes his condition or existence more pleasurable or less painful during intoxication than during abstinence. Finally, according to Crothers, inebriety is distinctly favored by malnutri- tion ; and hence uniformity in the time of taking food, as well as its good quality and ample variety and amount, should be the constant care of the company commander. No small proportion of soldiers who would resent the title of drunkard, take a quantity of alcohol daily sufficient to maintain a certain state or degree of stimulation for months at a time, exhibit no special peculiarities of conduct and attend to their duties with the utmost regularity. Such usually die from — or are discharged by reason of — some acute inflammation or chronic disease largely dependent upon alcoholic irritation. While it is obvious that any attempt at defining the limitations of this class must be purely arbitrary, it is considered by many authorities that any man drinking on an average more than two ounces of pure alcohol during the twenty-four hours — ^whatever be the form in which it is absorbed — may be included in this category. Prevalence of Alcoholism. — In the military service, the abuse of alcoholic liquors is one of the most potent factors by which efficiency is impaired ; and in the past, its effects were so apparent that drunkenness was largely looked upon as a distinctively military fading. Its influence as weU as its prevalence is indifferently shown by military statistics ; for all drinking men do not enter hospital for alcoholism, and a certain proportion of drunkards succumb to such various diseases as gastritis, cirrhosis of the Kver and nephritis, in the development and ultimate result of which the use of intoxicants has probably played no minor part ; further, the term alcoholism includes many pathological conditions and their symptoms, these varying according to the quantity of alcohol taken and the manner in which it is con- sumed. Chronic drunkenness occurs chiefly among old soldiers, and these steady drinkers, although their rates are higher, are not proportionately represented on sick report as compared with yoimger men, among whom the use of intoxicants more frequently occurs in the nature of periodical excesses requiring medical treatment. Acute alcoholism not rarely termi- nates life, and even at as recent a period as the decade 1886-95 it stood sixth in order of importance in determining the mortality among the white troops of the United States army. The proportion of discharges and con- stant non-efficiency from this cause is, however, low. The rates for alcoholism in our service have s'teadily decreased in the past fifteen years ; this having been accomplished through greater care in HABITS OF THE SOLDIEK AS AFFECTING EFFICIENCY. 809 the selection of recruits, a growing sentiment in. favor of temperance in the social class from which the soldier is drawn, greater effort on the part of the authorities for the early elimination of inebriates from the military service, and, finally and of the most importance, from the establishment of canteens, the favorable influence of which is subsequently discussed. The fol- lowing table shows the prevalence of alcoholism in the military forces of the United States during the twenty-eight years of peace, 1870-97, inclusive. Number of Number of Number of Number of cases admit- cases of de- cases admit- cases of de- _. Mean ted to hos- lirium tre- Tear. Mean ted to hos- lirium tre- strength. •"ir^" mens, per 1,000 strength. pltalj^er mens, per 1,000 8tren)?tti. streniftb. strength. strength. 1870 31,831 88.20 1884. . . . 34,034 62.10 # 1871 39,430 45.80 1885. . . . 34,138 53.50 1.57 1872 26,844 47.50 1886.... 33,573 42.80 1.01 1873 37,909 49.40 g 1887.... 33,841 46.70 .88 1874 37,f)21 58,10 c» 1888. . . . 34,726 40.20 .93 1875 33,575 68.00 S 1889.... 35,008 41.40 .51 1876 34,886 64.50 <3 1890.... 34,334 40.70 .86 1877 33,707 59.00 5 1891.... 23,269 40.00 .90 1878 33,381 59.40 £ 1892. . . . 24,203 37.20 .78 1879 23,964 65.10 & 1893. . . . 25,287 33.80 .55 1880 24,004 61.00 a 1894... 25,376 30.90 .83 1881 33,333 57.60 1895.... 35,304 30.10 .83 1882 33,339 68.70 1896... 25,119 38.80 .39 1883 23,439 66.00 1897. . . . 25,417 27.80 .58 * No figures available. In 1898, during the war with Spain, the admission rate fell to 15.1; the more active operations and novelty supplying much of the desired ex- citement, while the unusual conditions undoubtedly attracted a superior class of young men to the colors. The same was true in 1899, when the rate for alcoholism in the bulk of our army, engaged in hostilities and hard field service in the Philippines, was only about half as high as among the troops on the home stations, one-fourth as high as among those serving in Cuha and one-eighth as high as among those in garrison in Porto Eico. Admissions for Alcoholism and its Rbsults, pbb 1,000 op bach Class, 1885-97, Among Whitb and Colorbd Tboops. Tear. White troops. Colored troops. Average for whole qfmy. Tear. White troops. Colored troops. Average for whole army. 1885 1886 1887 1888 1889 1890 1891 1893 59.00 50.31 50.88 43.97 45.64 44.45 44.19 41.19 4.00 4.67 3.33 4.55 2.07 5.59 3.39 8.35 54.00 47.09 46.31 40.12 41.43 40.73 40.01 37.23* 1898 1894 1895 1896 1897 Decade. 1886-95. . 87,23 83.79 32.16 31.20 30.03 42.37 7.47 4.79 6.47 5.70 4.63 4.89 33.97* 80.94* 80.11 39.06 37.86 38.69* * Including Indian soldiers. The remarkable difference existing between the white and black troops of the United States service, as regards the prevalence of inebriety, is well illustrated in the above table, statistics for extended periods showing that there is approximately only one-tenth as much sickness from the use of 810 THEORY AND PEACTICE OF MILITAEY HYGIENE. alcohol among the negro as the white troops. Few colored soldiers are hard drinkers — and, as far as beer and other malt liquors are concerned, there apparently exists a racial distaste for these beverages on the part of the negro. It is a matter of frequent observation that where colored troops- replace white soldiers in a garrison, the canteen profits from beer and wine are greatly diminished, while the sales of cigars and confectionery are proportionately increased. This racial difference as regards the use of alcoholics is further shown by statistics for the British army, covering the European and non-Euro- pean troops iu the West Indies. During the year 1897, the admission rate for alcoholism, per thousand strength, was 15.6 for the former class, while the death rate was .74; for the native (negro) troops, during the same year, the admission rate was only .6, while the death rate from this cause was nil. Among white soldiers, nationality appears to be a factor of much im- portance in determining the relative amount of alcoholism. ' Thus for the seven-year period 1890-96, the rates of admission in our army, per thou- sand of each class, were as follows : Nativity. Admissions. American-born 38.51 German 26.63 English 51 .84 Irish 90.96 For the same seven-year period, the number of admissions for alcohol- ism, per thousand strength, was 46.27 for the artillery branch of the ser- vice, 45.30 in the infantry and but 19.72 in the cavalry. The lower rates for the last-named service are probably due to some extent to its more active duties, but chiefly to the fact that the negro troops at that time constituted one-fifth of the cavalry force and less than one-twelfth of the infantry. Alcoholism furnishes the single exception to the general rule that dis- ease of any character is much more liable to attack the young recruit than the old soldier ; the rate for alcoholism steadily increasing with age, where that for venereal disease, for instance, as steadily diminishes. Figures showing the influence of age upon the frequency of alcoholism, for the seven-year period 1890-96, are as follows: Age. Admissions per 1,000 of each class. Deaths per 1,000 of each class. Age. Admissions per 1,000 of each class. Deaths per 1,000 of each class. 19 and under. . 20-34 inclusive 25-39 30-34 3.87 9.17 32.35 42.45 0.02 .05 .20 35-39 inclusive 40-44 45^9 50-54 62.29 104.05 103.91 135.57 0.25 .73 1.51 1.83 That alcoholism should be less common among our young soldiers,, however, is only what should be expected. In civU life, the use of alcohol increases with age, and inebriety is most common among the middle-aged and the old. The development of drinking habits, from the tendency toward the use of alcoholics which may be possessed by the recruit, is naturally slow, and their iU effects are not usually manifested until such habits have HABITS OF THE SOLDIEK AS AEFECTING EFFICIENCY. 811 been established for some time. Further, as aheady shown, the standard of morality as regards the use of alcoholics is now much higher than it was a number of years ago, when the old soldiers, who now furnish such extremely high rates of admissions and deaths from alcoholism, were en- listed and received their first impressions in this respect. As to the amount of drunkenness existing in foreign services as com- pared with our own, no exact figures can be given — for the reason that milder cases do not appear on their hospital records, but are treated in quar- ters or infirmary. Comparisons in this respect, however, are not favorable to our own troops. The rates are, however, relatively high in England and Germany — much lower among the Latin nations, who are comparatively free from the vice of drunkenness. In France, where absinthe is largely consumed, the rates for alcoholism are said by Laveran to be only about one-tenth as high as in the English service ; and Viry states, that for the sixteen years 1875-90, the deaths from the use of alcohol in the French army amounted only to 11.5 in actual numbers annually — a considerable proportion of these occurring in Algeria. In Italy and Spain, the rates are even lower than in France — and during the occupation of territory by our troops as a result of the late war, it was a matter of common comment that an intoxicated Spanish soldier was rarely, if ever, seen. In both the British and French services, the amount of alcoholism is much greater among troops serving in the colonies than among those at the home stations. Results of Alcoholism. — The effects of alcohol upon the organism are numerous and varied. The mental symptoms are seen in delirium tremens, epileptiform convulsions, insomnia and sensory disorders. There are congestions of the alimentary tract, sometimes causing hemorrhage, the liver is speedily disturbed and the continued use of spirits results in its congestion and ultimately in the increase of connective tissue, as seen in cirrhosis. In the military service, however, whiskey-drinkers generally break down from other causes before a marked cirrhotic condition is reached. Gastric catarrh is set up by spirits, imperfect digestion foUows their excessive use, the nerve cells are changed and atrophied, the cardiac action is habitually hurried and often arhythmic, the heart muscle under- goes fatty degeneration and the arteries become atheromatous. The effect of moderate drinking, in the production of an increased amount of sickness other than that directly attributable to alcohoHsm, is well illustrated by the data collected by Carpenter relative to British soldiers serving in India, based upon 17,354 moderate drinkers and 9,340 abstainers. Of the former class, he found that one out of every 7.28 soldiers was admitted to hospital, where of the latter group but one out of every 14.47 was so admitted. StiU more favorable to the abstinence class were the figures obtained by him for the average number of days spent in hospital ; the moderate drink- ers losing 102 days where the abstainers lost but 36.4 days during the same period. In another comparison, it is stated that the admissions to military hospitals in India, during the year 1891, amoimted to 5 per cent, for abstainers and 10.4 per cent, for aU others. Madden states that in three benefit associations in England, 1884-88, there were lost by each laborer 26.20, 24.68 and 27.66 weeks through iUness — an average of 26.18 weeks —while dicing the same period the "Sons of Temperance," a society which admits total abstainers only to membership, showed the average number of 812 THEORY AND PEACTICE OF MILITARY HYGIENE. weeks lost by each member to be 7.48 ; a loss of time less than one-third that given in the other associations. As to the actual effect of alcohol upon the death rate, it is obvious that military statistics furnish imperfect information in this respect, since only acute cases of intoxication are noted on the records. Chronic alcoholism, however, while it practically does not appear as a factor in military statistics, imparts a peculiarly grave character to all diseases occurring in drunkards, and does much, through the organic changes, local congestions and nervous depression which result from the continued use of spirits , to bring about a fatal termination in any serious affection. According to Schmidt, in the fif- teen largest cities of Switzerland, where the causes of deaths are recorded by physicians without the names of the deceased being divulged, of all males twenty years of age or over, dying in 1891, alcohol figured as the immedi- ate or remote cause of death in 10.7 per cent., and in 1892, in 10.8 per cent. With regard to the use of alcohol upon marching troops, Eosse says : "The experience of the Ashantee War, in 1876, shows that alcoholic drinks are hurtful. The men who did not touch the supplementary ration of rum presented a mortality and morbidity inferior to the other soldiers." This statement wiU be supported by all who have served with troops on campaign. Drunkenness is one of the most frequent causes of insanity and suicide in the military service. In civil life, some writers attribute two-thirds of aU mental diseases to alcohol, and it is said to be the chief cause of self- destruction in England, Germany and Russia. According to Madden, in the years 1878 and 1879, it was found that in 27 per cent, of aU male lunatics in the asylums of Germany the existing mental derangement could be traced directly to the abuse of alcoholics. In Austria, according to Gauster, 40 per cent, of insanity occmrring in males could be ascribed to alcohoHc excesses. In the military service of our own country, no figures as to the influence of inebriety upon insanity are obviously available ; but for the seven years 1887-93, out of 134 suicides occurring during that period, alcoholism was officially reported as being the direct cause in 31.3 per cent. With regard to the effect of alcohol upon the performance of work, Frey draws the followiug conclusions: "Alcohol has an injurious effect upon the unfatigued muscle, in that it sensibly diminishes the amount of work the muscle is capable of doing. The feeling of fatigue is abohshed by alcohol, and for that reason the labor seems to be lighter." He further states that: "AU the pleasant sensations of physical and mental strength brought forth by moderate doses of alcohol are deceptive, and depend upon paralysis of the critical judgment and momentary blunting of the sensation of fatigue." The quickened circulation following the use of alcohol in small amount is accompanied by the subjective feeling of warmth. This sensation, how- ever, is whoUy deceptive and depends upon the primary relaxation of the superficial capillaries; but this very relaxed condition speedily reduces the temperature below normal, through the cooling of the blood as a result of its exposure to the atmosphere through the lungs and skin, and the stimu- lation of the sweat glands, with the increased loss of heat through evapo- ration. Further, alcohol interferes with the oxidation of fatty food and in this respect impairs the power of heat-production. Wood states that the HABITS OF THE SOLDIER AS AFFECTING EFFICIENCY. 813 bodily temperature in simple intoxication may fall as much as 3° C. ; the fan in temperature varying directly with the quantity of alcohol taken, and the reduction of temperatxu-e being less marked in the case of chronic alco- holics than in those less habituated to its use. Hence the individual under the influence of alcohol perishes from exposure to cold much more quickly than one who is sober. As to the effect of drunkenness upon military morals, no argument is required to show that the infractions of discipline recurring with each pay day are largely the result of alcoholic stimulation. It was noted of the British troops in India, in 1891, that of all minor offences but 1.5 were committed by abstainers where 6.7 were committed by moderate drinkers. Smart states : " The medical and court-martial records after pay-day, in all camps where whiskey can be procured, furnish data sufficient for insistence on its exclusion as the cause of much disease and many injuries and acci- dental deaths." As expressed by Parkes: "When debarred from spirits and fermented liquids, men are not only better behaved, but are far more cheerfvd, are less irritable, and endure better the hardships and perils of war. The courage and endurance of a drunkard are always lessened; but in a degree far short of drunkenness, spirits lower, while temperance raises, the boldness and cheerfulness of spirit which a true soldier should possess. If spirits neither give strength nor sustain it against disease, are not protective against cold and wet, and aggravate rather than miti- gate the effects of heat; if their use even in moderation increases crime, injures discipline and impairs hope and cheerfulness ; if the severest trials of war have not been merely borne but most easily borne without them ; if there is no evidence that they are protective against malaria and other diseases^then the medical officer wOl not be justified in sanctioning their issue, or their use, under any circumstances." And Woodhull adds: "It is not necessary to insist, from theoretical or medical grounds alone, upon the mischief that alcohol causes soldiers. The observation of any officer of experience is enough. Liquor, besides weakening men physically, tam- pers with their will-power, disturbs then temper, makes them less trust- worthy even when sober, is at the bottom of almost every violation of discipline, and is the one agent that can convert a regular force into a mob. The absence of liquor usually means a clear guard-house. Abun- dant liquor means a heavy sick list, a large guard report, and a general feeUng of doubt as to the command. It foUows without saying that if the use of alcohol is hurtful in a personal and in a martial sense to the private soldier, who is the lowest unit in the military scale, it is very much more mischievous in its ultimate consequences when an officer, who is so potent with those beneath him, is its victim." That there are very rare emergencies in which alcohol might possess a certain value, either to supplement an insufficient issue of food or to gain a temporary stimulus at the expense of subsequent depression, may perhaps be admitted. It is certain, however, that, under nearly all conditions of military service, alcohol in any of its forms is only mischievous to the soldier. It is of interest to note, in this connection, that alcoholics still enter into the rations of most foreign armies, either as a daily or an occa- sional issue. Thus brandy is issued to the German troops during war ; rum to the English ; rum or brandy to the French ; brandy or wine to the 814 THEORY AND PEACTICE OF MILITARY HYGIENE. Portuguese and Spanish ; wine to the Italian, and brandy to the Austrian and Eussian soldiers. Prophylaxis. — Every effort should be made by officers for the preven- tion or dimiuution of drunkenness among troops. The dangers of the use of liquors should be fully explained to the men ; and while admitting that the soldier possesses the moral right to use alcoholics in moderation should he so desire, he should, at the same time, be made to understand that on passing the bounds of intoxication he becomes a proper subject for mili- tary discipline. Offences agaiast sobriety, if in any way capable of inter- fering with the performance of duty, should be uniformly and severely punished ; and advantage should be taken of existing regulations to elimi- nate confirmed inebriates from the service as soon as possible. Company and commandiug officers and court-martials should co-operate to this end. Troops are thus freed from the harmful influence of these men, and their summary punishment furnishes an example by which others will assuredly profit. Every attempt shoiild be made to arouse a wholesome sentiment on the part of the more steady men against the inebriates, and special care should be taken to impress the former class with the fact that the penal- ties imposed for alcoholic excess are largely for their own protection, since they are the ones upon whom the execution of the unperformed duties of the delinquents must devolve. The better men should be made to under- stand that the drunkard, far from being an object of pity or worthy of consideration, is an encumbrance upon the military community of which they endeavor to form a worthy part and for whose derelictions they are thus the chief sufferers. "Where such self-interest can be aroused, drunk- enness is soon looked upon by the men as a vice rather than a failing — the inebriate wiU not be shielded by his fellows or his offence condoned. In reducing the proportion of alcoholism among troops — aside from the summary discharge from the service of all confirmed inebriates, as above mentioned — no soldier should be re-enlisted who has shown an undue fondness for strong drink, and no discharge should be given him in which this defect is not plainly set forth. Acquaintance with military duties does not compensate for the pernicious effects, direct or indirect, produced by the drunkenness of old soldiers. A most potent factor in reducing the rates for alcoholism would be the exercise of greater care on the part of recruiting officers in refusing to accept any man as a recruit who has the slightest appearance of being addicted to the use of intoxicants. Experi- ence has shown that recruiting officers are generally inclined to be too lenient in this respect. Much can be done to prevent alcoholic excesses through the proper administration of the canteen, and by the provision of suitable and sufficient employment and recreation ; since, as already stated, a large proportion of drunkenness is the result of ennui. So far as the offending individuals themselves are concerned, the invmable treatment of acute alcoholism in the manner required for narcotic poisoning — by emesis, catharsis, cold douches and through lavage of the stomach — will do much to bring about the desired reform. Eepetition of this unpleas- ant but efi'ective treatment will rarely be necessary. In determining the occurrence of alcoholism among troops, the example set by officers, in this respect, is of great importance. Nothing is more certain than that a drunken captain will have a drunken company. HABITS OF THE SOLDIER AS AFFECTING EFFICIENCY. 815 The Canteen System. — No discussion of alcoholism among soldiers would be complete without reference to the canteen, which, more than any other factor, has operated to the welfare of troops and the promotion of temperance. This institution, officially known as the post exchange, had its origia in our service at Vancouver Barracks ia 1880, but it was not unto. February, 1889, that it was officially recognized by the War Depart- ment and rules and regulations for its establishment and government were published to the army. The purpose of the canteen, as officially announced, is to supply troops with goods at a low rate of profit and to afford rational recreation and amusement to aU enlisted men. The sale of ardent spirits is strictly pro- hibited therein; but commanding officers are authorized to permit light beer and wine to be sold by the drink, on week-days, to a room set apart for the purpose, when in their opinion such action is promotive of temper- ance. Gambling of any character is forbidden. Each canteen is managed by an officer selected by the post commander for his fitness for the posi- tion, he being allowed one or more enlisted men as assistants; imder re- cent orders, civilians only being allowed to serve as bar-keepers. As show- ing the favor with which the canteen system was received by troops, it is only necessary to say that, in 1894, five years after its inauguration, there were seventy-five canteens in successful operation in our service, and that during that year the total receipts were $1,417,079.62; of which sum no less than $304,649.91 were returned to the men as dividend profits, or about one dollar per month per man. During the year ending June 30th, 1898, the aggregate receipts of the exchanges in operation in the army amounted to $1,621,398.67, and there was received as money on deposit $189,- 258.81 ; making the total amount of money received $1,810,657.48. There was expended for merchandise purchased, rent, fixtures and repairs, and expenses of operation, $1,297,737.16 — which, less deposits, gave a profit of $323,661.51. From this amount, donations to the funds of the several regimental bands aggregated the sum of $9,154.51; to the maintenance of post gardens, $1,559.17; to post libraries, $640.06; to gymnasia, $2,- 913.75; as prizes for the encouragement of athletic sports, $3,336.41, and, after setting aside the sum of $60,877.58 as a reserve fund to meet the anticipated expenses for at least one month, the sum of $254,890.93 was returned to the members in the form of dividends. The effect of the introduction of the canteen system upon sick rates with respect to alcoholism, as shown by the reports of the surgeon-general, was prompt and marked. For the decade 1878-87, the average number of ad- missions for alcoholism and its direct results amounted to 64.28 per thou- sand of white troops. This rate diminished during the next ten years, in proportion as canteens were gradually established at various posts, omit- ting fractions, in the foUowing ratio: 44, 46, 44, 44, 41, 37, 34, 32, 31, 30. On observing the admissions for alcoholism for the seven years 1885-91, which immediately preceded the general establishment of the canteen system upon a satisfactory basis throughout the army, it is found that a yearly average of 1214.8 men found it necessary to apply for treat- ment from this cause ; while for the six years 1892-97, after canteens had been generally established throughout the army, an average of only 928.4 men required medical care as the result of alcoholism — a reduction 816 THEORY AND PRACTICE OF MILITARY HYGIENE. amounting to 23.6 per cent. In 1890, there were 17 posts at which the admission rate for alcoholism exceeded 10 per cent, of the strength. In 1891, the number of such posts had decreased to 11, and in the six sub- sequent years diminished at the following rate: 10, 7, 4, 5, 2, 2. This favorable showing for the army at large was duplicated in the case of each individual post ; the introduction of the canteen, at a military station, in no instance failing to be promptly followed by a diminution of alcoholism. For certain stations this improvement was extraordinary. In 1889, Wil- let's Point had an admission rate for alcoholism of 222.97 per thousand. For 1890, the year during which the canteen was established at that post, it fell to 157.50, and in the next year was reduced to only 70.46. At Fort Spokane, the amount of sickness resulting from intoxicants was reported by the surgeon as having diminished fifty per cent, during the six months following the institution of the canteen. At Fort Douglas, in 1888 and 1889, the total number of admissions attributed to alcoholism amounted to about 85 per thousand strength; while during the period 1892-94 this rate feU to 52.95 per thousand strength — and such instances might be largely multiplied. All are agreed as to the value of the canteen in the tropics, as well as at home stations, in reducing alcoholism. A report by O'EeiLly upon the condition of the British troops in Jamaica, states that the canteen, from which the men can always procure beer, has been largely instrumental in the disuse of stronger spirituous liquors and in a lessening of the evils which followed the free use of spirits in the tropics. In referring to the condi- tion of the Fourteenth United States Infantry at Manila, CardweU. ex- presses his belief that a great improvement shown in the figures for vene- real and alcoholism in this regiment was due to the establishment of a canteen, kept under admirable discipline, and he adds: "Cool American beer as a substitute for the ' beno ' of the native gia-shops has a most beneficent effect." From Porto Eico, the report of the inspector-general is as follows : " The post exchanges of this department have been the means of elevating the enlisted men by keeping them away from low and cheap resorts and the worst elements of Porto Eican society. I have noted that the exchange as operated in the department has reduced instead of iacreasiag drunkenness, and by the profit of operation, which is divided among the enlisted men, has greatly increased and improved the messing of the sol- diers — thereby his happiness and health — by providing him necessities and luxuries not otherwise obtainable." Eeports of this character could be mul- tiplied almost indefinitely; the views of nine-tenths of the officers and men, nearly a thousand in number, whose opinions on the canteen were officially asked by the War Department, in 1899, being favorable to the institution as at present operated. The cases of delirium tremens will be accepted by all as furnishing re- liable data by which the gravity of the admissions for alcoholism may be determined. It is therefore of interest to observe that for the seven-year period above noted, prior to the complete adoption of the canteen system, the average annual admissions for this cause, actual numbers, was 23.8; while for the six-year period following the general establishment of this sys- tem the average number of men admitted yearly for dehrium tremens was 16.6 — a reduction of 31.3 per cent, in this serious class of cases. It can HABITS OF THE SOLDIER AS AFFECTING EFFICIENCY. 817 scarcely be doubted that this remarkable decrease was chiefly influeuoed by the general substitution of beer — a milder beverage, which rarely pro- duces deHrium tremens — for distilled liquors, the free use of which is well known to result in great mental excitement and nervous exhaustion. It is recognized that alcoholism and insanity are closely related through the direct influence exerted by intoxicants in the production of mental aberration. Hence it is not surprising to find that the average number of cases of insanity, annually coming under treatment, was 35.1 for the seven- year period, 1885-91, prior to the complete establishment of the canteen system, and only 24 as an annual average for the six subsequent years, 1892-97. These figures show a reduction in insanity amounting to 31.7 per cent. As to the number of days of service lost annually from kisanity, the improvement since the institution of the canteen is even more marked. Figures for the years 1885 and 1886 are not available; but for the five- year period 1887-91 the average number of days lost was 1,563, while for- the six years 1892-97 the service annually lost to the Government from, this cause amounted to only 924.5 days — a decrease of 40.9 per cent. The canteen, for the maintenance of good order in which a commis- sioned officer is held responsible, is an aid to discipline as well as to the health and morals of troops. It provides a resort which, while under thorough military control, offers iaduccments to the men to remain at home and spend their idle time within the limits of the post ; this condi- tion obviously being far preferable to the one formerly existing when the nearest and generally patronised places of amusement and refreshment were the grog-shops, usually with gambling-room and brothel annexes, which marked the Limits of each military reservation. Except with the most dissolute class of men, the soldier is well satisfied to patronise the canteen to the exclusion of outside saloons; knowing, as he does, that he receives good value for his money in articles of excellent quality, and fully appreciating that the profits of the institution ultimately accrue entirely to his benefit, and are not, as with the case of outside establishments, di- verted to the advantage of others. Besides the congenial resort which it furnishes, the influence of the profits of the canteen in promoting content- ment among troops can scarcely be overestimated ; contributing, as they do, to improvement of the food, the attainment of wholesome amusement and the provision of much by which the soldier's life is made less irksome, and he himself rendered more efficient in the performance of his military duties. Year. Average strength. Deserted. Per cent. of desertions. Tear. Average strength. Deserted. Per cent. of desertions. 1885 24,816 24,365 24,438 24,790 25,564 24,930 24,525 2,626 2,012 2,525 2,678 2,730 1,922 1,398 10.6 8.3 10 11 11 7.7 5.7 1892 24,869 25,670 25,661 25,209 25,143 25,300 1,410 1,632 936 1,341 858 726 5 7 1886 1893 6 3 1887 1894 8 6 1888 1895 53 1889 . . 1896 8 4 1890 1897 39 1891 Average for seven years before canteen system was thoroughly established 9.18 Average for six years after can- teen system was thoroughly established 4 53 The best index of the contentment of troops is to be found in the rate of 52 818 THEORY AND PRACTICE OF MILITARY HYGIENE. desertions, since it is obvious that the soldier who is well satisfied with his lot will not endeavor to escape from the performance of his military obligations. That the canteen system has, from this standpoint, operated to the general welfare of the men is undoubted ; the desertions and per- centage of desertions in the regular army, from 1885 to 1897 inclusive, being as given in the previous table. From the above table, it is observed that during the first year after the canteen system was officially established the rate of desertions fell 30 per cent., while in the next year the rate was further reduced to 48 per cent. For the five years previous to the establishment of the first officially recog- nized canteen, the number of men annually deserting from the service, per thousand strength, amounted to 101; while for the eight years immedi- ately subsequent to the institution of this system the annual number of desertions was reduced to 50 per thousand strength. The decrease noted has been practically progressive — and it will be seen that for the two years immediately prior to the war with Spain scarcely one-fourth the number of men, as compared with the average for the three years immediately prior to the introduction of the canteen system, found the military service so uncongenial as to desire to escape from completing their terms of enlist- ment. These results are certainly most gratifying, and there is no reason for believing that, with the development of the canteen along its legiti- mate lines of growth, a still further decrease in the present small rate of desertions may not be confidently anticipated. Drunkenness is certainly prevented by the constant military super- vision to which the canteen is subjected. The men themselves are usually careful not to indulge in alcoholics to the point of inebriety ; while such few individuals as are inclined to be forgetful of the dangers of excess will usually be restrained by companions, or by those connected with the establishment — who have no personal interest in promoting the sale of liquor, as does the saloon-keeper of civil life — from passing the bounds of actual intoxication. When such a condition has actually resulted, the drunken individual will rarely be left to his own devices or permitted to become offensive, and is usually prevailed upon by others to return to barracks without committing any breach of discipline. Hence brawls and disturbances — with resulting court-martial — have, since the introduction of the canteen system, become relatively infrequent, and pay-day, formerly synonymous with debauchery and riotous disturbance, is now scarcely to be distinguished by its effects from any other day. As illustrating the marked reduction of convictions for drunkenness or complications arising therefrom, since the establishment of the canteen system, the following figures given on the following page, from the reports of the judge-advocate-general, are of interest. From these figures it is evident that, coincident with the general es- tablishment of the canteen system throughout the army, there has occurred a decrease amounting to considerably more than one-half the drunkenness which formerly tended to the impairment of discipline, the demoralization of individuals and to the occurrence of assaults, injuries and deaths. It is idle to deny that this excellent result has not been largely due to the attraction furnished by the canteen, combined with the military discipline which prevails in that institution and which reduces to a minimum the possibility of dangerous excesses. HABITS OF THE SOLDIER AS AFFECTING EFFICIENCY. 819 Tear. Total number of trials and convictions in the army. All causes. Number of trials and convictions for drunkenness and conditions arising therefrom. Year. Total number of trials and convictions In the army. All causes. Number of trials and convictions for drunkenness and conditions arising therefrom. 1886 1,640 1,730 1,999 1,752 1,907 2,000 2,198 2,189 842 289 357 423 407 417 228 163 1894 1,728 1,486 1,384 1,245 1,838 1,605 120 1887 1895 142 1888 1896 168 1889 1897 143 1890 1891 1892 1893 Average for six years 1886-91. Average for six years 1892-97. 372.5 160.6 The influence of the canteen in promoting order and contentment is less directly, though none the less positively, shown by the number of soldiers making savings-deposits with army paymasters. For the above periods, the figures given in the report of the paymaster-general for 1899 show that the average number of men annually making such deposits, for the seven years 1885-91, was 7,273; while for the six years 1892-97 the annual average so depositing was 8,382 — an increase of 13.3 per cent. Such an increase can be interpreted only as meaning that a larger number of men found the service so congenial that they purposed to serve their en- tire enlistment without the thought of a possible desertion with its for- feiture of deposits. Also that a greater proportion of soldiers found that their pay, with the greater value given by the canteen in return for their money, was in excess of their immediate needs ; and further, that the re- striction of gambling— brought about by its prohibition in the canteen and the lessened frequenting by the men of resorts in which gaining, often of a dishonest character, was a prominent attraction — kept the money dis- tributed among the many and prevented its accumulation by the few or its loss to outsiders. It may be also that the constant example set by the canteen as a successful co-operative institution was not without its effects in promoting soberness and steady business habits throughout the com- mand. A saving class of men is naturally a law-abiding class, and it cannot be denied that the average annual increase for the latter period mentioned above, of 1,109 men who had practically placed themselves under bonds to the Grovernment for their good behavior and continuance in the service, was not without a powerful influence in raising the morale of the troops and promoting their efficiency. That this, indeed, was act- ually the case is demonstrated by the figures relating to desertions and court-martials already given. The opportunity given the men of purchasing light, nutritious lunches in the canteen is certainly of much benefit. Many articles of food not obtainable in the company mess are thus brought within reach, and the monotony which often pertains to company cookery may in this manner be agreeably interrupted. It is probable, too, that this feature does much to prevent the intemperate use of alcoholics. The gastric cravings of hearty and idle men are thus satisfied, and a sandwich with the glass of beer largely decreases the desire for an additional quantity of the latter. It is claimed by the advocates of total abstinence that by the sale of beer in the canteen the health and morals of the soldiers are impaired; 820 THEORY AND PRACTICE OF MILITARY HYGIENE. that such tacit encouragement on the part of the Government favors in- dulgence in alcoholics and that drinking habits are thus formed by those who might otherwise have remained sober men. These objections are purely theoretical and are at variance with facts as observed since the es- tablishment of the canteen. The sale of beer, under suitable restrictions, undoubtedly results in good rather than evil to the troops at large, and may justly be looked upon as a safety-valve for those accustomed to regard the use of a certaia amount of liquor as both harmless and proper. Com- paratively few men to-day become inebriates from a taste for alcohol ac- quired in the military service; and where certain individuals may imbibe too much beer on pay-day, they constitute a class which, in the absence of a mild beverage of this character, would probably resort to stronger liquors — frequently sophisticated — outside the limits of the command. That beer- drinking, viewed in the abstract, is unproductive of good will be admitted by all; that when properly controlled, its sale ia canteens, rather than its prohibition, redounds to the general health, morals and military effi- ciency, few, if any, who are conversant with the subject would attempt to deny. It is certaiuly unfortunate that the temperance element in civO. life which is so constantly endeavoring to enact legislation against the sale, in the military service, of alcoholics of any character, cannot be brought to regard the matter from the practical rather than the sentimental aspect and thus assist in controlling and largely curtailing an evil which it is powerless to prevent, and which, if its efforts toward restrictive legislation should be successful, would undoubtedly be greatly increased. At present its efforts toward the abolition of the canteen merely oppose theory to facts and sentiment to statistics. It may here be remarked that the view is commonly entertained, by the civil class just mentioned, that the soldier is peculiarly dissipated above all others and requires special legislative measures to safeguard him against his weakness ; the fact being wholly ignored that the army is recruited from the general community and merely reflects the qualities of the latter, whether they be good or bad. The recruit brings with him into the ser- vice the result of the moral moulding to which he has been subjected dur- ing childhood and youth in civil life, and does not change his nature or moral standards with the mere donning of the uniform. The vice of drunkenness is certainly neither initiated nor aggravated as a result of military service, and, if the opinions held by some outsiders are correct as to the moral conditions obtaining in the army, then the cause must be sought for within the social classes and the conditions of environment from which the human material composing the army is drawn. It is certain that no more drunkenness has existed in the army during the past few years than occurred in the corresponding classes of civil life — if indeed there was not less. As already stated, it is intended that the canteen should provide a place in which the rational and profitable occupation of leisure time may be encouraged ; and it is obvious that this object is not attained by the mere establishment of a bar. The canteen should be fitted up like a club, and should possess, in addition to the bar and lunch features, facilities for billiards, card and game-rooms, reading-room and library. If the beer- selling feature of the canteen is given undue prominence, the better and HABITS OF THE SOLDIER AS AFFECTING EFFICIENCY. 821 essential character of the resort suffers. Hence the bar should merely be an adjunct and not constitute, as is sometimes the case, the most important part of the institution. No alcoholics should be sold until two hours after the men have breakfasted, to avoid the possibility of early morning tip- pling aud the greater danger resulting from the use of alcohol on an empty stomach. Seats and tables in sufficient number should be provided, and druiking at the bar discouraged. The present regulations forbidding the practice of treating should be strictly enforced. In the British service, at cer- tain stations, it is customary to limit the amount of beer sold to each man — usually to about three pints daily — and this practice might with advan- tage at certain times be adopted in our own service. With men of known tendency toward inebriety, either the quantity of alcoholic's with which they may be furnished should be carefuUy defined, or they might be en- tirely debarred from purchasing beverages of this character. Any possible ill effects from the sale of light wines and beer would be largely prevented by the supply, gratis, of a certain amount of cheap but nutritious food — not of a thirst-producing character — to all purchasers of alcoholics. The use of credit, at stated periods and in limited quantities at posts where more restrictive measures are not in vogue, would be of benefit as affording less opportunity for excess at any one time. On the other hand, so much credit should not be allowed that the soldier would find his entire resources swallowed up in his indebtedness, and thus become discontented. The canteen should close at a comparatively early hour, so that uisuffi- cient rest on the part of the soldier, whose day begins early, need not be chargeable against it. Undesirable characters, civilians of either sex, should be excluded from the canteen^ and every care taken to observe all sanitary precautions and maintain due cleanliness. Eating and drinking at all other places in the vicinity of the camp or garrison should be dis- couraged, since it is undoubtedly the case that infectious diseases are often dispersed through the uncleanly methods of irresponsible venders of articles of food, alcoholics and temperance drinks. Particidarly is this the case in the relation of water-borne diseases to non-alcoholic beverages — to which class of drinks many outbreaks of cholera and typhoid fever have been justly attributed. Coffee should be kept on hand and sold at cost rates. In the tropics, the establishment of aSrated-water machines in connection with the canteen would often be of advantage; waters of this character being both wholesome, cheap and popular. At present there is a strong tendency by some officers to utilize the canteen — and stimulate the sale of beer — solely as a means of increasing the company funds. This should be strongly opposed, and the profits of the institution regarded as the happy result rather than the cause of its existence. It would be much to the advantage of troops if the allotment to company funds was officially limited to fifty per cent, of the profits ; twenty-five per cent, being expended to further athletic sports and amuse- ments among the men and the remainder to be reserved as a contingent fund for fixtures, improvements, insurance and similar purposes. In general, the regulations for the government of the canteen, while rational and comprehensive, should not be too severe, lest the popularity and hence the value of the resort be impaired. This point requires the exercise of much discretion. It should be understood that the institution, 822 THEOEY AND PRACTICE OF MILITARY HYGIENE. while naturally a great benefit, may become a positive evil to troops if the officer in charge is remiss in his obligations, indifferent or incompetent. Temperance Clubs. — In the British service in India, an attempt is being made to diminish drunkenness among troops by the substitution of coffee-houses for the canteen. While Kbraries, recreation rooms, workshops, gardens and cricket-grounds had been established for many years, it was not until 1887 that a further development was made by bringing together the regimental and company clubs and forming them into what is now known as the "regimental iastitute." The aim and object of these "in- stitutes " are to improve the social condition of the soldier and to reduce in- temperance by the provision of such reasonable comfort and physical as well as mental recreation as to make them a center of attraction and lessen the habit of seeking entertainment elsewhere. This plan has now been put into operation in nearly every regiment in India. As to its effects, it was reported by Lord Roberts, in 1890, that an improvement following its introduction was apparent, as was shown by the following figures for the troops in Bengal : 1888. 1889. Total number of men punished, per cent Number of cases of insubordination witli violence Number of cases of drunkenness tried by court-martial . . Number of men sentenced to imprisonment with hard labor Number of men discharged with ignominy 2.34 307 149 957 110 S.Ol 257 781 79 0.33 50 51 176 31 In the Bombay forces, the results are equally satisfactory — but the con- ditions were reversed with troops in the Madras Presidency. Put in the most appreciable form, the following figures give all the convictions by court-martial, as compared with the preceding year : In Bengal the num- ber of courts-martial decreased by 14.11 per cent. In Madras the number of courts-martial increased by 1.22 per cent. In Bombay the number of court-martials decreased by 17.29 per cent. Should the total-abstinence element of the coimtry succeed in abolish- ing the canteen, as at present existing, it would seem as if the establish- ment of such a central recreation-room and temperance club would be advis- able ; although that such an institution can take the place of the canteen, in the promotion of temperance among the large class of soldiers who enjoy an occasional glass of beer, cannot for a moment be admitted. Such men would seek their beer outside the limits of the reservation, in the resorts which would spring up like mushrooms were the canteen abolished. There can be no doubt that the aggregation of a number of means of amusement under one roof does much to increase the individual value of each. VENEREAL DISEASE. Occurrence.^ — Of aU the causes by which the soldier is brought ia sick-report, in time of peace, venereal disease is of the most importance and affects his efficiency to the greatest extent ; this being particularly the case in our own service as compared with most foreign armies. HABITS OF THE SOLDIER AS AEFECTINO EFFICIENCY. 823 The foUowing table shows the ratio of admissions, per 1,000 strength; for all forms of venereal disease in the principal armies of the world, largely compiled from official figures furnished the commission lately in- vestigating the prevalence of venereal affections in the British army. 8 1 a S3 ^3 .2 1 Ill 1 Great Britain. Tear. Home stations. maia stations." 1873 63 109,3 203,3 191,0 1873 56 101.7 167.6 181.6 1874 38.4* 53 93.5 145.7 207,5 1875 31,6 59 110.4 139.4 213,5 1876 57 38.8 65.8 107.6 146.5 203,5 1877 57.8 30 66.9 97.7 153.2 234,4 1878 59.7 36 75.4t 97.8 175.5 291,6 1879 63.7 38.5 81.4 95.1 179.5 353,3 1880 65.8 34.9 75.7 96,7 345.9 249 1881 60.6 39.2 79 91,8 245.5 259,6 1883 63 41 73.7 78,4 346 365,5 1883 58.9 38.3 73.3 76,6 360 271.3 1884 53.1 34.5 73.5 75 370.7 293,5 1885 50.7 33.6 69 79,6 275,4 342,6 1886 49.6 39.7 65.8 71.9 367,1 385,8 1887 51.6 38.6 64.4 47. 5 .... i "9,3 74,37 253,9 361,4 1888 46.7 36.3 65.4 43.^ : 76. 5t .... S $9,7 80,88 334,5 373.3 1889 45.8 26.7 65.3 40.' r 66. 6 .... S !4,7 84,66 313.1 481,5 1890 43.8 26.7 65.4 43 73, 4 96 i !7,3 75,33 212.4 503.6 1891 43.7 37.3 63.7 41. > 5 71, 5 60.4 i 57.5 73,46 197.4 400.7 1892 44 27.9 61,6 44.( 3 69 53.1 i J6 76,73 201.2 409,9 1893 43.8 64.5 43. 93, 3 45.8 . 73.08 194.6 466 1894 40.9 64.8 39. 3 93 54,3 . 80.4 182.4 511,4 1895 61 36 84. 8 48,1 . 73,7 173.8 533,3 * In the case of Germany, 1873-74, 1874-75, and so on. + Bosnia and Herzegovina were occupied in this year. t Compulsory examination of prostitutes abandoned. Among European armies, that of Germany has by far the lowest rate for venereal disease. Eussia and France come next, then 4-u.stria-Hungary, then the troops of Holland serving at the home stations, then Italy. No army included in the above comparison, except that of Great Britain, has as high a rate as that shown for the United States forces ; and with us, moreover, the actual prevalence of venereal disease is probably greater than the returns indicate, through the concealment and self-treatment so often practiced by the men in the milder cases, by the use of patent medicines. The small amount of disease of this character in the army of Japan is notice- able. In all the above armies, with the exception of those of Great Britain and the United States, some special regulations are in force for preventing the spread of venereal affections. These generally consist of weekly or fortnightly examinations of the men for the detection of venereal disease — non-commissioned officers and married men being in some cases exempted — and registration and periodical examination of all women ascertained to be leading a life of prostitution, with compulsory isolation of such as are found to be diseased. In the Italian army, regulations of this latter kind were revoked in 1888. In the case of most of the armies mentioned above, the comparison with respect to various forms of venereal disease may be carried ijito further de- tail, as foUows : 824 THEOEY AND PEACTICE OF MILITAEY HYGIENE. Mean Annual Admission Rate, pbk 1,000 Strength, pok the Three Years 1890-92. 1 4 1 >> 1 Dutch Troops. Bkitish Troops. Home stations. East Indies. Home stations. In India. Primary and secondary 5.5 31.8 9 84.9 13.1 39.9 13.9 57.4 16.83 57.96 14.8 55 47.0 408.6 101.7 101.9 175.4 All other venereal dis- eases 263.6 In these years, it is apparent that the German army had scarcely more than one thirty-second, and no European army had as much as one-eleventh of the amount of syphilis as devastated the British troops in India. The Dutch troops in the East Indies, with an exceed- ingly high rate of venereal disease generally, did not suffer from syphilis one- third as much as did the British soldiers serving in India — where the rate ha3, moreover, risen rapidly since the period included in the above comparison, while in the Dutch East Indies it has materially de- clined. The figures with regard to syphilis show much less of this serious affection among European armies, excluding England, than exists among our own military forces. Among venereal dis- eases, syphilis is of partic- ular importance as direct- ly influencing the military efficiency of an army. This affection, even at its best, seriously undermines the constitution and ren- ders the soldier at all times less resistant to invasion by acute disease and to a fatal termination. Even in such cases as are ulti- mately returned to duty, the men have frequently been in hospital for con- siderable periods and are s § CO o =1 § g s s o g S o s s s o , s s s s s s o o o o o - g o ■^ f a t- > < ? < O z g z I i -1 i < 5 z i X a 1- ' ■ 4 Q t 1- -NIVIIUQ 1V3UD •ONVmOH a -t-3 o P' .S9S O EC 11 52 p I HABITS OF THE SOLDIER AS AFFECTING EFFICIENCY. 825 prone to later manifestations from a temporarily latent infection. In such instances, the state has not only paid the man for the time he was unfitted for duty but receives back a doubtfully efficient soldier, extremely liable to break down under the fatigue and privations of field service. The prevalence of syphilis in the United States army, duiing thirty years of peace, is shown by the following figures : Year. Admissions to hospital, per 1,000 strength. Year. Admissions to hospital, per l,0OOstrength. Year. Admissions to hospital, per 1,000 strength. 1868 105 97 69.4 67.7 60.3 55.7 47.3 60 59.6 50 1878 1879 1880 1881 1883 1883 1884 1885 1886 1887 47.7 44.3 49.4 47.6 40.1 35.6 39.8 24.8 33.3 23.9 1888 1889 1890 1891 1893 1893 1894 1895 1896. 1897 22.3 1869 33 1870 19.7 1871 14.7 1873 16 1873 13.6 1874 14.1 1875 11.1 1876 10.9 1877 13 During the year 1898, the admissions for this disease were only 10 per thousand; in 1899, they were 14.38 for the tropical islands and 13.49 for troops serving in the United States. As is seen by the above figures, syphilis has steadily diminished since the Civil War down to the year 1898 — and to one-tenth of the amount existing in 1868. While it is probable that a certain proportion of this reduction is due to a more accurate differ- entiation between the hard and soft venereal sores, the gratifying fact never- theless remains that the reduction in syphilis among our soldiers has not only been great but steadily progressive. While in the various armies on the European continent the tendency is rather toward a reduction than an increase of syphilitic infection, in the British army at home — and particularly among the British troops in India — a serious feature of recent years has been the disproportionately great in- crease in the amount of primary and secondary forms of this disease. This growth was not great prior to 1884, when the Contagious Diseases act was revoked, but since that time the advance has been appalling. In the following tables, the rapid development of syphilitic disease among the British troops in India is well shown; figures for primary syphilis not being given for the period prior to 1887, as the hard chancre was not differentiated from the non-syphilitic sore until that year — and then only in part. Sbcondaky Syphilis. (Ratio of admission per 1,000 strength.) Year. Admissions. Year. Admissions. Year. Admissions. 1873 32.4 30.4 25.2 25.1 23.9 33.1 1878 22.1 24.1 23 23.1 23.3 23.5 1884 24,4 1873 1879 Mean for years 1872-84 1885 1874 . . • • 1880 23.3 1S75 1881 28.7 1876 1883 1886 33.3 1877 1883 1887 29 4 826 THEOKY AND PKACTICE OP MILITAEY HYGIENE. Tear. Primary syphilis. Secondary syphilis. Year. Primary syphilis. Secondary syphilis. Tear. Primary syphilis. Secondary syphilis. 1887 1888 1889 75.5 73.1 134.3 39.4 33.4 51.3 1890 1891 1893 185.6 104 103.6 66.3 60 57.8 1893.... 1894. . . . 1895.... 139.8 173 174.1 61.6 74.6 84.9 In 1893, from the British troops in India, venereal disease of all forms caused 466 admissions per 1,000 strength. No less than 2,619 men, or more than the equivalent of two regiments, were constantly in hospital throughout the year from this cause. Each case required treatment for thirty days, and the rate for each soldier of the entire army was twelve days lost. The admissions for syphilis m all its stages were 275 per 1,000. Of 70,642 British soldiers serving in India on the 15th of July, 1894, 19,892, or 28 per cent., had been admitted to hospital for syphilis since their arrival in India. Only 26,247 men, or 37 per cent., had never suffered in or out of India from any venereal disease. Of the 13,- 000 soldiers who returned to England from India in 1894, over 60 per cent, are reported as having suffered from some form of venereal infection. In 1895, an average of 45 men out of every 1,000 were constantly in hos- pital for venereal disease. These figures, however, by no means represent the total amount of inefficiency due to this cause. Many cases of secon- dary syphilis, in the last few years, have been treated in the British service by hypodermatic injection of mercury, without admission to hospital, and do not, therefore, figure in the returns ; while a large number of men who are nominally cured are only fit for light duty under peace conditions. Among 5,822 men detailed for field service with the Chitral relief force, 462, or nearly 8 per cent., had to be rejected for venereal disease; 279 more, or an additional 4.5 per cent., had subsequently to be transferred from the field hospitals to the base for the same cause. The report of the Departmental Committee says: "In 1895, venereal disease attacked the British troops in India to an unprecedented extent. Out of the enor- mous total of 522 cases of venereal per 1,000 troops, syphilis contributed nearly one-half, i.e., 259 cases per 1,000; a figure many times greater than the highest of which we can find any record in the statistics of con- tinental armies, for recent years, either at home or abroad. Venereal disease caused more than one-third the total amount of sickness, the constant dis- ablement of 3,200 men out of a total force of 71,000 and a vast amount of partial disability and unfitness for any but routine duties." Concerning the campaign in India in 1897, it is stated that out of an actual strength of 16,600 British troops, 1,481, or nearly 7 per cent., were found to be disqualified for service through venereal disease. It is probable that there is less syphUis among our troops than exists among the unmarried male civilians of the same class, since those soldiers who are recognized as infected are promptly discharged from the military service in nearly all instances. For the same reason, syphilis does not figure to any extent in the death rate. Among such few affected mdi- viduals as may be retained in the service, the effects of syphilitic infection are slow and insidious, and manifest themselves in unfavorably modifying other affections. Thus such affections as Bright's disease, cirrhosis of the liver and amyloid degeneration are undoubtedly largely induced by it. HABITS OF THE SOLDIEE AS AFFECTING EFFICIENCY. 827 GonorrhcEa, in contradiction to syphilis, has been steadily on the in- crease ia our service for the past fifteen years ; thus showing that there has been no improvement in the morals of the United States soldier as regards the maintenance of chastity. In 1885, the admission rate was 37.76 per 1,000 strength, while in 1897 the rate was 56.21 per thousand. For the year 1896, the number constantly sick from this cause in the British ser- vice was 9.15 per thousand as compared with 3.22 in the United States army for the same period. In 1890, the admissions in the French army for gonorrhcea, per 1,000 strength, were 27.9. Causes Affecting the Prevalence of Venereal Disease. — The in- fluence exerted by race upon the prevalence of venereal infections is not, in general, sufficiently appreciated. A marked difference in this respect exists even among the various armies of Europe, where similar measures of prophylaxis are employed; but it is when the rates for Asiatic forces are compared with those for white troops, serving under the same conditions, that the greatest difference is observed, and particularly so with reference to syphilis. It is certainly true that this disease, introduced compara- tively recently among the Caucasian and negro races, commits far greater ravages among those in which it has not long prevailed, than among peoples who have presumably acquired a comparative immunity to the affection, transmitted through a syphilized ancestry extending through scores of gen- erations. It appears to be true, also, that certain races possess in large degree peculiar powers of resistance to gonorrhoeal infection, a quality long since demonstrated to exist in certain individuals of even the most suscep- tible peoples. The following table, taken from the report of the commission investi- gating the prevalence of venereal diseases among the British troops in India, shows the great difference in the admission rates for syphilis and all venereal affections among Europeans and Asiatics, per thousand of strength. Akmt in the Dutch East Indies. Akmy in British India. Tear. Dutch troops. Native troops. BrltlsU Troops. Native Troops. 1 si 1 fi & ^11 1890 53.9 43 44 40 37 483.9 443 440.9 370 416 11.0 11.6 9.7 8 7.8 248.0 243.6 323.5 218 191.8 201.9 164 160.4 190.9 347.6 503.6 400.7 409.9 466 511.4 18.3 16.3 17.1 17.9 17.7 41.1 1891 37.9 1892 39.6 1893 1894 36.4 33.3 Mean for five years. . 43.6 424.7 9.6 335 195 458.3 17.4 37.5 In the Dutch East Indies, the Asiatic troops suffer from all venereal diseases but one-half as much, and from syphilis about one-fifth as much, as do the Europeans. In the British army in India, the native troops are not affected with venereal diseasee one-twelfth as much, nor from syphilis one-eleventh as much, as are the white troops. It is probable that, in India, caste feeling helps to deter the native soldier, to some extent, from 828 THEORY AND PRACTICE OE MILITARY HYGIENE. consorting with the lowest and. most dangerous class of prostitutes — but his remarkable freedom from venereal infections can be satisfactorily ex- plained only on the gi-ound of racial insusceptibility. It is of interest to note that while the admission rate for British troops in India has more than doubled since 1881 in respect to venereal disease, among the native troops there has been no appreciable increase during this period. An inference which may be legitimately drawn from this fact is that venereal disease has not increased to any remarkable extent among the loose women of the country generally, but that among the class with whom the British soldier associates there has been an increase out of all proportion to their numbers, directly as a result of such relations — ^both the native women and the British soldiers presenting rates far in excess of their racial normals. As between whites and negroes, the greater resistance to venereal diseases lies with the former, probably through a longer exposure to the processes of immunization through heredity. Comparative figures for these two classes in our own service, for all venereal diseases, are as follows : Tear. Aamission rate per 1,000 strength, whites. Admission rate per 1,000 strenffth, colored. Tear. Admission rate per 1,000 strength, whites. Admission rate per 1,000 strength, colored. 1884 75.00 80 No figures. 73.13 78.08 84.86 73.03 70.64 101.00 76 No figures. 95.98 98.51 83.75 105.39 80.18 1893 75.71 74.94 82.21 75.57 80.04 81.80 78.48 138.59 86.94 1885 1893 49 1886 1894 47.46 1887 1895 53.26 1888 1896 56.53 1889 1897 114.60 1890 1898 149.58 1891 1899 195.93 No satisfactory explanation for the sudden and marked reduction in the above admission rates for the colored troops during the period 1893-96 can be offered. The experience of the British in the West Indies shows a higher percentage of venereal infections among the colored troops than among white soldiers — syphilis being more than twice as common among the former as among the latter. This difference with respect to syphilis holds good, also, in our own service ; the admission rates for the several classes of venereal disease, per thousand of each class, being as follows : White Troops. Colored Troops. Syphilis. Gonorrhoea. Chancroid. Syphilis. Gonorrhoea. Chancroid. 1898 9.39 13.39 51.18 78.16 17.91 37.04 28.44 33.43 67.29 109.82 54 05 1899 63 67 A second point well worthy of careful consideration is found in the fact that venereal infection, particularly that of a syphilitic nature, appears to take place more certainly, and to assume a much more severe character, when relations are entered into between individuals of different racial characteristics than when both are of the same nationality ; the aliens suf- fering, in this respect, to a greater degree than the resident population. Troops quartered among a foreign but not hostile population almost inva- riably suffer worse in respect to venereal diseases than do those at home. HABITS OF THE SOLDIER AS AFFECTING EFFICIENCY. 829 In the Austrian army, a large increase in affections of this character fol- lowed the occupation of Bosnia and Herzegovina in 1878; the French troops in Algeria are more affected with venereal diseases than those in France, and the same is true to a marked degree in the case of the British troops in India and that of the Dutch in Java. The proportion of venereal disease is higher among our troops outside the limits of the United States than among those serving at home stations. In speaking of the native troops stationed in Bengal, it has been said that the " Gurkhas, being foreigners, have higher rates (for venereal disease) than other native troops." These conditions, however, do not obtain when a command is moving or during / S /' N y s N •s"" HKt s / S \ t ■) N JtfO / ■ 5s 'ffO ( eo 9 % _ Fig. 369.— Chart Showing the Influence ol Laws Controlling and Regulating Prostitution In Eohllkhand District, India, and Cape Town, South Africa, upon the Admissions, per 1,000 Strength, for Primary and Secondary Syphilis from the British Troops Stationed at these Points. (After Browning.) Black Hue, Cape Town ; dotted line, Rohllkhand. Cape Town, without Regulations, 1884-1888, average 371. Rohllkhand, " " 1889-1896, " 370. Rohllkhand, with " 1884-1888, " 132. Cape Town, " " 1889-1897, " 168. measures were gradually removed, show that a progressive increase of vene- real diseases has taken place among the British troops serving in India ; and there is unfortunately no assurance that this increase has reached its limits." In the year 1889, a Contagious Disease act was brought into force at Cape Town, South Africa, and at the same time all regulations for check- ing the spread of venereal disease were abolished in India ; so, for a period of eight years, it is possible to compare India, minus regulations, with Cape Town and a Contagious Disease act m force. For the five years previous to the act coming into force at Cape Town, the average admissions among troops on that station for primary and secondary syphilis were 371 per 1,000 of strength. The troops in the Rohllkhand district of India, for the years 1889-96, had almost exactly the same proportion of admissions, viz. : 370 per 1,000, neither station being under a Contagious Disease act. For the nine years 1889-97, after prostitution was officially regulated, the ad- missions for venereal disease at Cape Town were reduced to 178 per 1,000 HABITS OP THE SOLDIER AS AFFECTING EFFICIENCY. 835 strength; while Eohilkhand, during the like number of years, 1880- 88, prior to the removal of aU official control over prostitution, had nearly the same number of admissions for this cause, 134 per 1,000. The chart on page 834 graphically shows the influence of the acts upon the ad- missions for syphihs ; the heavy vertical lines marking the abolition of all restrictions in India being followed by an immediate and extraordinary increase in the number of cases of this disease, and also showing the point at which unrestricted prostitution in Cape Town came under official control, a remarkable and permanent decrease resulting. To such an im- answerable argument as to the value of controlled prostitution it would be almost superfluous to add. Browning states that previous to restrictive measures comiog into force at Cape Town, venereal diseases of all kiads were rampant and the admis- sions to the military hospitals, for these affections, appalling; the latter having reached a rate of 828 per 1,000 strength. The average for the years 1884-88 for all forms of venereal disease was 674 per 1,000, while the average for the years 1889-97, after prostitution was regulated, was only 349. This was not a gradual fall which might be accounted for by an improvement in morals, but a sudden descent, as shown in the foUowing 1} It 94 W *», la w /a 87 « » IS t» M K n ai la M » IS M /« U IS M 7d 9» •.H r- 773 r I / ■- \ 700 / \ / \ 1 \ / \ «3.5 \ J \ S.W \ • \ •>7.5 \ - • \ . S. H aU nti in '*! nee urn ( s ^ >- \ ^ / ^ ^ \ sis lUU " ' "' S / • \ s. 1 ' f \ JiSO \ . \ 1 \ ns ) ^ ■ ino _ rie. 370.— Admissions for AH Venereal Diseases, per 1,000 Strengtli, Among the British Troops at Cape Town, Showing their Relative Prevalence Belore and Alter the Begulation of Prostitution. The ver- tical lines mark the institution of official control. (After Browning.) diagram, from 828 per 1,000 in 1888 to 347 per 1,000 in 1889. In 1897 the rate had been further reduced to 216 per 1,000. Browning concludes that the Contagious Diseases act of the Cape of Good Hope has "been the means of preventing thousands of soldiers in the garrison at Cape Town from being incapacitated by venereal diseases " and that "the men who stOl contract such complaints suffer from a milder form than existed prior to the act coming into force." He believes that "the act is a humane one, relieving the sufferings of hundreds of prosti- 836 THEOEY AND PRACTICE OP MILITARY HYGIENE. tutes and also alleviating the distress of women who, though not strumpets, contract venereal disease." In the province of Pinar del Rio, Cuba, during its recent occupation by United States troops, the following order was published and enforced : " Clandestine prostitution will not be tolerated. Prostitutes shall be regis- tered. They shall live in such locations as are indicated. Each prosti- tute shall have a book. In this her name, age, nationality and address shall be recorded. She shall be examined at least once a week by a physician, and the examining physician shall sign the book. This exami- nation shall be good only for one week. Any prostitute engaging in her trade when her book is not signed to date shall be punished. She shall not change her residence without the permission of the sanitary inspector. The proprietors of houses of prostitution will be held accountable for the condition of the houses, and of the inmates ; also for the orderly conduct of those living in or visiting such houses. No liquor shall be sold, given away or drunk in houses of prostitution. Each prostitute will be required to provide the means necessary for securing her own and her visitors' cleanliness. Cases of venereal disease must be at once reported to the sanitary inspector. When venereal disease is traced to any particular person, such person will be subjected to punishment." As to the results which followed the enforcement of this order, the chief surgeon of that department writes : " In connection with the matter of regulated prostitu- tion, this command has been in Cuba three months and numbers 3,000 men. These men have free access to the towns. I have not been able to find more than nine men who have contracted venereal disease in the De- partment of Pinar del Rio." In certain cities of the Philippine Islands, similar rules for the regula- tion of prostitution have been enforced. At Jolo, in the Sulu archipelago, the occupation of the town by our troops was followed by the appearance of about forty Japanese prostitutes. At first no effort was made to control these women, and, according to Steer, much venereal disease appeared in the command. As a result, the regulation of prostitution was decided upon ; strict rules were enforced, among them being the weekly examiaation of the prostitutes and the exclusion of all outside individuals, as sailors and com- mercial people, from the houses. A lock-hospital was also opened, which the women were compelled to enter upon the slightest suspicion of venereal disease and in which they were kept until their recovery was complete. With regard to the men, frequent inspections of the person were made. Some difficulty was experienced with cases of chronic gonorrhoea, as the services of as many men as possible were required, but the problem was finally solved by making up the garrison of a detached block-house from such cases, with an officer detailed to command them and a member of the hos- pital corps assigned to ensure the proper carrying out of treatment. Under these precautions, the amount of venereal disease was reduced to less than one per cent. ; there beiag but five cases of venereal under treatment, at the time of the report, out of a command of seven hundred and fifty men. To show the effect of this system in reducing venereal. Steer states that from one battalion which came to Jolo after service in the islands of Cebu and Leyte, inspection showed seventy-eight men with venereal infections — a number being syphilitic. On the arrival of this battalion, the houses of HABITS OF THE SOLDIEE AS AFFECTING EFFICIENCY. 837 prostitution were closed, and kept so untU the men had been inspected and those who were diseased had been isolated and prevented from transmitting their affections to others. As a result of the control of prostitution at Job, not a case of primary syphilis has occurred among the soldiers during the year its regulation has been enforced, the venereal diseases which do oc- cur are mild in character and are notably free from the complications so frequently observed in other parts of the Philippines. The prostitutes are restricted to certain houses and are rarely seen on the streets or at the windows, so there is little to shock the casual observer. As a result of the presence of these women, trouble with the surrounding native Mahommedan population is avoided. In the report concerning the sickness among the British troops com- posing the Dongola Expeditionary Force, in 1896, the chief medical officer says : " On first arriving at Wady Haifa there was some trouble found in checking clandestine prostitution. There were a large number of native women who were living just outside the English lines, and it was from these women that the men contracted disease. There was a licensed brothel under supervision in the native town of Wady Haifa, and the inmates were periodically examined. Very few cases of disease were con- tracted there. Stringent police precautions were taken and a military patrol was placed outside the camp to prevent women from coming near, and this answered so effectively that after a few weeks the nuisance was almost stopped and there were hardly any admissions afterward for vene- real." For the period 1863-65, the Italian army had an admission rate for venereal disease of 120 per 1,000; this faUing in 1874-76, as the result of sanitary inspection and careful control of prostitution, to 66 per 1,000. In 1888, under the influence of English ideas, the Italians abolished the regulation of prostitution; a venereal rate of 47.5 per 1,000 strength, of the previous year, being increased to 66.6 in 1889 and 93.3 in 1893. In view of such facts as are quoted above, there can be no doubt that the intelligent regulation of prostitution results in a great decrease in vene- real; this to be accomplished by a system including careful registration, official surveillance and weekly medical inspection, so that the addresses of prostitutes may be known, their movements traced and any diseased condition recognized. The latter requirement is of the greatest impor- tance — a fact of which the British Sanitary Commission in India was fuUy convinced when it recently reported,: "We are satisfied from the evidence that the frequent examination of women is the most efficacious method of controlling the disease." These examinations should be made in private and only in the presence of official examiners. Clandestine prostitution should be discouraged as far as possible, as furnishing a high rate of venereal. Colin noted that of 32 syphilitic French soldiers, 14 were infected by public prostitutes and 18 by women employed in so-called wine shops. All common prostitutes should be segregated within well-defined limits and public solicitation severely pun- ished. Brief printed instructions should be furnished these women as to the dangers and prevalence of venereal, and the importance of cleanliness as a measure of prophylaxis. Next to medical inspection, it is probable that care in maintaining cleanliness of the person is the most important 838 THEOEY AND PEACTICE OP MILITARY HYGIENE. factor in preventing the spread of disease venereal ; it having been experi- mentally determined that infection from the non-syphilitic venereal sore may usually be prevented by a thorough cleansing of the parts with soap and water if done within ten minutes from the time of exposure. When dis- eased, such public women should be at once isolated in a proper institution until restored to health. Apart from the great importance of such action upon the general welfare, it is also a matter of humanity to these unfor- trmates that they should have the benefits of medical treatment, with rest and care in hospital, until they are cured. Obedience to these regulations should be enforced by police authority; but public exposure, as far as the occurrence of venereal disease is concerned, should be prevented as far as possible. It should not be forgotten that when official control becomes too rigorous the number of avowed public women undergoes diminution while clandestine prostitution increases. The proposition is not here advanced that the Government should provide prostitutes for troops, as has been done by the British military authorities in India, nor that a native concu- bine should be officially allowed and supported for each soldier, as is said to be the case at present with respect to the Dutch troops at certain sta- tions in Java. There should be no official encouragement of vice ; but the regulation of vice is not its encouragement, and such women as have vol- untarily chosen to adopt a life of prostitution and who come within the sphere of military control, as may well be the case under many circum- stances, should be prevented, so far as possible, from spreading loathsome disease among the men whose health it is the duty of the sanitary officer to guard — the latter, in this manner, indirectly shielding the civil population to which the soldier returns on his discharge. That the men who consort with prostitutes do so at their own risk is a specious argument which might be applied as justly with reference to any other infectious disease. The public welfare must be consulted, for the soldier himself is frequently not the only sufferer from his transgressions, but may transmit his affec- tion, in many ways, to the innocent. With the ethics of the question the sanitary officer ha^ nothing to do. Prostitution always has existed, and probably will continue to do so while the world lasts and human nature is weak. The most severe laws of ancient times, even the death penalty, failed to stamp it out. The military service finds these social conditions — it does not create them — and it is the duty of the sanitary officer to limit and modify their effects by every means possible. Of these, the regulation of prostitution is the most efficacious. Since military garrisons often attract to their vicinity lewd women of the lowest character and largely subjects of venereal affections, great care should be taken to prevent loitering or importuning by this class, or by their male associates, within the limits of the command. Particularly in the tropics it is desirable that no females should be employed in or about the barracks, since there is evidence that such women are fi-equently the source of aggravated forms of venereal disease. In addition to the control of the women chiefly concerned in its dis- semination, the prophylaxis of venereal disease among troops requires the application of suitable preventive measures to the soldier. The large amount of venereal disease occurring among troops. — a condition entirely preventable and dependent upon vicious indulgences — has led many to HABITS OF THE SOLDIER AS AFFECTING EFFICIENCY. 839 suggest the imposition of penalties upon such soldiers as may offend ia this respect. It has been proposed that those incapacitated for duty from this cause be deprived of their pay while rendering no service to the Gov- ernment; that their privileges be restricted or that confinement be im- posed. In the French army, a period of imprisonment was at one time imposed upon every venereal case after discharge from hospital; but, as this led the men to conceal their diseased condition from the medical officers and either go without treatment or place themselves in the hands of unqualified practitioners, the order was revoked. It is certaialy subversive of discipline and unjust to the more moral class of men to require them to perform the extra duty which results from the entrance into hospital, as a result of their own misconduct, of those on whom such duties should right- fully have devolved. Such a condition practically puts a premium upon participation in vice, and apparently the only way by which the latter can be punished is through compulsory inspection of the person, as is required in the German army. Quite recently this plan has been tried iu several commands of our own service and has not aroused the opposition on the part of the men which was at first anticipated ; it would be of much sanitary ad- vantage if the plan were more generally adopted. During the occupation of Cuba, an order was issued on this subject in the Department of Ma- tanzas, of which the following is an extract : " There should be a weekly examination of all the enlisted men ia the command made by the medical officers, and the company commanders should be required to be in attend- ance. The men should be stripped and this examination should be com- plete as far as relates to any outward evidences of venereal disease or other infections. A list of all the men found infected with venereal troubles should be made out under the direction of the company commander and posted conspicuously on the bulletin-board or in the barracks of each company organization. Among these thus affected, only those who are actually incapacitated from performing their duties should be placed on sick report, the others being required to perform aU duties. The privileges of the canteen and all pass privileges should be withdrawn from all whose names are thus posted and extra severe punishment meted out to those who are detected violating this rule. As soon as any one thus listed is, in the opinion of the surgeon, free from all manifestations of venereal infection the surgeon should notify the company commander, so as to enable the latter to take his name from the list. This course cannot be construed into actual punishment of the enlisted men, for the reason that in taking away his canteen and pass privileges it is merely in the nature of removing _ the causes which tend to retard his recovery. A weekly inspection is necessary, as there is no other way by which it can be determined whether or not the individuals are infected." Where measures for the control of prostitution can be carried out, the soldier affected with venereal disease should be required to state where and from whom it was contracted, with a view to the proper segregation and treatment of the woman indicated. In the British service, however, dur- ing the existence of the cantonment laws, some difficulty was met with, according to Welch, in the attempt to identify the source of venereal infection through the unwillingness of the soldier to expose his co-partner in vice. 840 THEORY AND PRACTICE OF MILITARY HYGIENE. Under present conditions, many soldiers affected with venereal disease hesitate to declare its existence through the official publicity necessarily given to such cases, and their reluctance to have their names entered upon the records in connection with affections of this character. Thus of two companies aggregating 170 men, which had recently returned from two years' service in Porto Rico and which were inspected by the writer, no less than 37 cases of concealed venereal disease were found, of which 11 were syphi- litic. These had not been declared through fear that they might prove a possible obstacle to re-enlistment or the subsequent attainment of a pension. As a result of failure on the part of the soldier to report his condition, the latter, in many instances, is aggravated by being left either without treat- ment or by the employment of patent medicines or unskilled advisers; while the sufferer is a constant source of danger to his associates. Where venereal disease is concealed, the offender, if detected, should be severely punished ; and it should be thoroughly understood by the men that it is greatly to theh own interest, in the way of cure, to declare the existence of such an affection as soon as its appearance is noted. Further, all non-com- missioned officers, knowing of the existence' of cases of venereal disease in their troop or company, should be held responsible for the prompt appear- ance of the sick men before a medical officer. A soldier who chronically exposes himself and -undergoes repeated infection should be regarded as morally unfitted for the military service and a candidate for discharge. Such a man is- a nuisance in a company and is so regarded by the good men, who shun his contact and are suspicious of the bath-room and other conveniences which aU use in. common. Spending a large part of his time in hospitals, the services of such a man are often of but little value to the Government. It would certainly be of advantage to the military service if short lectures by medical officers, particularly at recruiting depots, were delivered at suit- able periods for the purpose of acquainting soldiers with the grave and far-reaching consequences that are likely to result from immoral conduct, particularly with respect to clandestine pr'ostitution ; the importance of early treatment in the case of venereal disease and the dangers resulting from its concealment ; the intractable character of syphilis and the necessity for prolonged medication ; the dangers resulting to the healthy from the presence of concealed venereal disease in barracks. It is a question whether a general discussion of the personal means sometimes employed in the prevention of venereal infection would be advisable ; and the sanitary officer should carefully avoid assuming a position which might be construed by the men as in any way favoring the practice of sexual gratification. Chastity should be inculcated, and the too common idea that sexual con- tinence increases sickness and mortality should not be encouraged. USE OF TOBACCO. The moderate use of tobacco, both in garrison and in the field, may be regarded as necessary to the comfort and happiness of the average soldier. It is certain that among many individuals the want of this article causes even more hardship than the lack of food ; and its deprivation, as a means of punishment, is said to figure among the disciplinary measures of the HABITS OP THE SOLDIER AS AFEECTING EFFICIENCY. 841 German army. In the military service, tobacco is ordinarily employed for smoking, and its use for chewing is as exceptional among soldiers as it is frequent among sailors. Smoked in moderation after meals, it stimulates gastric secretion, aids digestion and increases peristalsis; where the supply of food is insufficient, it markedly diminishes the sensation of hunger. Korloff , during the last Eusso-Turkish War, specially studied its properties in the latter respect, as a result of which he recommended that a daily allowance be issued to the Eussian troops ; and in our own service tobacco has wisely been incorporated as one of the components of the emergency ration. Experience shows, however, that smoking during the heat of the day, particularly while on the march, increases thirst and leads to unneces- sary drinking — the same result, through the loss of salivary fluids induced by frequent expectoration, following the use of tobacco by chewing. Tobacco promotes reverie, overcomes weariness, relieves ennui and over many individuals has a markedly soothing influence. In camps of long standing, the soldier sooner or later becomes fretted by the monotony of the life, and tobacco is largely used; nominally to help pass the time but in reality for its sedative influence on an unemployed nervous system. Under the latter conditions, its consumption may become sufficiently great to demand the attention of the medical officer, for excess in its use is pro- ductive of positive evils. Arnold considered it to be an abuse of tobacco if the daily consumption of this article, per man, exceeded half an ounce. It is impossible, however, to predetermine the minimum quantity which would be harmful to each individual — but shortness of breath, obscure pains around the heart and nervous irritability are indications to reduce or abstain from the use of tobacco. More pronounced symptoms resulting from its use are loss of appetite and impaired muscular force, vertigo, alteration of vision, loss of memory and progressive weakeniag of the mental faculties. In general, however, tobacco can be regarded as harmful only to soldiers of a highly neurotic tendency and to those of insufficient will power properly to restrict its use. Whatever its possible theoretical dangers, the hospital records of our army demonstrate that little justifiable criticism can be made of the present use of tobacco by American soldiers, nearly all of whom habitually employ it without the production of any ILL effects whatever. Smoking should be prohibited ia barrack dormitories and allowed only in the open air or in rooms specially designated for the purpose. The ia- dividual hygiene of the smoker consists in maintaiaing cleanliness of the mouth and of the pipe, cigar- or cigarette-holder employed; in abstaining, from the practice of inhaling the smoke into the lungs, from smoking be- fore breakfast and in a proper limitation of the amount of tobacco consumed. TATTOOING. This is a wide-spread custom of great antiquity, especially common among people of a rudimentary civQization.- Among such, it is used not only for purposes of adornment but also as a means of readily identifying the individual and determining his nationality. Among civilized peoples it is affected chiefly by those of a low social and criminal class, and may 842 THEOEY AND PRACTICE OF MILITARY HYGIENE. fairly be looked upon as one of the stigmata of degeneracy; the more in- telligent men not being partial to this method of ornamentation. A large proportion of tattooed recruits are enlisted from cities and large towns. Among soldiers, imitation is the most important factor ia inducing tattoo- ing, the great majority unthinkingly following the example set by others — a former sailor being frequently responsible for the performance of this operation on the persons of his comrades. Much of the tattooing noticed on recruits will be found to have been done on the appearance of the geni- tal function ; often in commemoration of an attachment, illicit or other- wise. The marking is generally limited to those parts normally covered with clothing, the site most commonly selected beiag the anterior aspect of the forearm — though other portions of the body, as the arms, legs and trunk, are not spared. As observed by the recruiting officer, the most common devices are initials, dancing and nude female figures, flags, ships, anchors, wristlets, hearts and clasped hands. This form of decoration is usually resorted to from motives of vanity. Others are selected as being symbol- ical of occupation, as the whip and horseshoe, or as indicative of feeling or state of mind, as shown by an embracing couple. Indecent designs, so common among the criminal classes, are not seen in our military service, since the possession of tattooing of this character constitutes a bar to en- listment. In city-bred recruits, particularly those who have had a street life, small dots are frequently noted on the web between the thumb and first finger. These, varying in number from two or three to eight or nine or more, irregularly distributed or arranged ia circular, stellate, triangular or rectangular form, are evidence of membership in certain organizations, serving the same purpose in handshaking as the fraternal grip of more pre- tentious and laudable societies. The operation of tattooing, among soldiers, is done by pricking; and tattooing by scars, though abrasion of the cuticle, is not common. The coloring matter employed is usually India ink, wood-charcoal or perhaps laundry blueing — the red color being given by vermilion. The operation not rarely causes inflammation of the lymphatic glands and sometimes abscess. More rarely a condition of marked sepsis results, and Berchon cites four cases in which amputation of a limb was required for this reason. As usually carried out, the colors are moistened in the palm of the hand with the saliva of the operator. The men who do this work are sometimes affected with constitutional disease; and Chenisse, Eobert, Bergasse and others have observed a large number of instances where syphilis has been transmitted by this procedure. This is especially common in the tropics, where the native operators are not exceptions to the more general syphiliza- tion of their race. In the same way, inoculation with tuberculosis has fre- quently occurred ; Callings and Murray reporting an interesting series of cases in which the tuberculous manifestations appeared from three weeks to one month after tattooing done with colors rubbed up with the saliva of a phthisical operator. As to the proportion of tattooed individuals in the military service, Lombroso noted that of 2,739 Italian soldiers only 1.2 per cent, were so marked, while as much as 10 per cent, of more than 6,000 adult crimi- nals had subjected themselves to the operation. For the German service, Baer found the above condition to be reversed ; only 2 per cent, of crimi- PLATE VIII. Common Fobms of Tattooing Among Soldiers. HABITS OF THE SOLDIEE AS AFFECTING EFFICIENCY. 843 nals being tattooed as compared with 9.5 per cent, of soldiers. For our own service, no definite figures upon this point are available, but the pro- portion of tattooed soldiers is certainly very considerable. AKUSESEEITTS OF THE SOLDIEB. The monotony of life in garrison, and especially among troops on foreign service or in encampments of long standing, will, unless inter- rupted, become extremely irksome. Under such conditions, nostalgia is very liable to develop, especially among young recruits and new regiments. This affection was very common among the volunteer troops first sent to the Philippines, affecting officers as well as men ; one Nebraska regiment having at one time 95 cases reported by the regimental surgeon as "No diagnosis, probably nostalgia." In many instances, the medical officers themselves were affected with this complaint and the result was a sick-list wholly out of proportion to the actual disease present. After the novelty of strange environment and new duties has worn off, the soldier suffers from sameness of occupation and — sooner or later — from the results of comparative idleness. All officers serving with troops should fully appre- ciate that ennui is at the foundation of much of the physical and most of the moral evils by which the efficiency of the soldier is impaired. Idle- ness, discontent, insubordination, vice and sickness occur in logical se- quence ; and, while most ofl&cers wiU possess internal resources affording congenial occupation to themselves, suitable employment and means of dis- traction must be found for the enlisted men. For this purpose, a sufficient amount of fatigue work daUy, if carefully planned with reference to a definite object, wiU do much toward maintaining the mental and moral as weU as the physical tone of troops ; besides, at the same time, providing many comforts and ministering to the ever-present sanitary needs of the command. Where work of this sort is scarce, it should be so economized as to provide a few hours' employment daily — for the time soon comes when drills alone cease to afford sufficient diversion. Work merely for work's sake is undesirable and promotes discontent, but troops wUl cheerfully per- form any labor which apparently tends to their safety and comfort. Marches into the surrounding country, temporary camps from garrisoned posts, field manoeuvers, the construction of entrenchments with practical illustration of their defence and attack — all are methods of maintaining the mental, physical and military efficiency of the command. Pedestrianism should be particularly cxiltivated among infantry troops and prize matches ar- ranged for suitable occasions. In cavahy commands, trick and Cossack riding will be valuable to both men and animals. Horse-racing affords an interest to all ; and target practice — not formal duty-firing, but competi- tive trial between teams from different organizations — will give a break in the monotony. Hunting and fishing should always be encouraged among troops as affording a most valuable means of recreation and change of diet; at the same time familiarizing the soldier with the use of his weapons, with the topography of the surrounding country and with the science of woodcraft. Gymnasium work, applied gymnastics and athletic field-sports not only improve the physical condition but also the mental state of the men. Field-days for competitive athletics should be held at suitable in- 844 THEOEY AJSTD PRACTICE OP MILITARY HYGIENE. tervals, and all out-of-door games, especially such as football and lacrosse, should be encouraged in every possible manner. It is especially during the enforced monotony of winter camps, or with small detached commands in the tropics during the rainy season, that sys- tematic effort should be made to amuse and interest the men. The frequently narrow quarters and perhaps imperfect means of maintaining cleanliness, the confinement within doors by the condition of the roads and weather, the long uneventful waking hours, the prolonged sexual abstinence and the tread-mill round of minor and annoying drudgery^ — all tend to disturb the nervous balance and lead to attempted relief. If alcoholic liquors can be obtained at such times they are much abused, and the excesses tell on the nervous system by depressant action. Gambling is the favorite excite- ment of many in spite of its official prescription ; and prolonged sessions, implying loss of sleep and disorders of assimilation, are held in cramped positions and frequently foul atmospheres. Much too common a vice, gambling should be discouraged in the military service as tending to de- • velop a class of sharpers who fleece their comrades and beget bad feeling directly to the prejudice of good order and discipline. Under the above con- ditions, tobacco and excessive sleep are resorted to as aiding to pass away the time under conditions of ennui ; while vicious dealings with the generative function may, with certain individuals, be called upon to furnish in this way the nervous excitement required. To turn the attention into more healthful channels, varied indoor amusements, in addition to outdoor sports, should be officially encouraged. Eeading-rooms and small libraries should be estab- lished, and dramatic and variety entertainments projected. Under aU cir- cumstances, music dispels mental depression and stimulates and enlivens those under its influence. Bands are of great value, especially with unsea- soned troops ; and the formation of musical clubs among the men should be encouraged for this reason. Literary and debating societies introduce a town-meeting element which has no place in the military service ; nor is it reasonable to expect the greater portion of the enlisted force to become greatly interested in intellectual pursuits. For this class of men, the canteen fur- nishes a congenial club in which their social needs are best satisfied. With large commands, men can always be found possessing special talents — as actors, vocalists or athletes — for amusing others; and such should be promptly sought out, organized into a company and encoiuaged by official recognition and assistance in catering to the amusement of the troops. Under the monotonous conditions of camp life, officers wiU do well to encourage the energies, while directing the efforts, of the leading spirits of their commands. There are always certara men of initiative in creating diversion and such carry the mass with them and bring amuse- ment to all. Their efforts should be promoted in every possible way, as being of the gi'eatest value in the prevention of ennui and discontent. In large commands, an officer should be detailed to take charge of aU public amusements^ — including theatrical performances, shooting, racing and com- petitions of all sorts. If active and enterprising, he will keep many names off the sick-list and tide the command through the period of tedium with undiminished nerve force. It may be added in this connection that "the effect of aggregating or massing together a large number of men is a peculiar psychological prob- HABITS OF THE SOLDIER AS AFFECTING EFFICIENCY. 845 lem. A mob may readily be induced to perform acts the most illegal and irrational; and an army, if the contradiction of terms may be employed, is a disciplined mob. Men who, at home, are correct and digniiied mem- bers of society, when gathered into an army and removed from home re- straints will speak and act in violation of propriety, decorum and law. The tendency to a disregard of law, hygienic as weU as other, be- comes the rule rather than the exception. The lapse of time and the power of discipline may diminish this tendency to lawlessness, but it never en- tirely disappears from an army in which fighting is not the constant busi- ness of life." INSANITY AND SUICIDE. Mental diseases have undergone a considerable diminution in our ser- vice during comparatively recent years; this undoubtedly resulting from the greater provision officially made for the intellectual needs and recre- ation of the soldier, together with the concentration of troops near large centres of population. With the present establishment of small garrisons throughout the tropical islands, an increase in insanity may be expected. Among our troops on foreign service, home-sickness appears to be a potent factor in producing a condition of melancholia. During the past three years, the isolation of troops, their lack of knowledge of the native lan- guage, their enforced confinement to garrisoned towns, and the con- stant nervous strain incident to continued preparation against attack by the enemy, all combine to produce a mental condition, which, for want of a better name, is called insanity, and which is often completely and effec- tively cured by the trip from the Philippines to the United States. That the condition is a serious one is evidenced by the fact that the majority of suicides occur in this class of cases. The following figures show the rates for mental diseases in our army for a period of thirty years : Year. Admissions per 1,000 strength. Tear. Admissions per 1,000 strength. Tear. Admissions per 1,000 strength. 1868 1.7 1.5 3.1 3 2.4 3.2 1.8 2.2 1.4 1.6 1878 1.5 1.9 2.1 3.5 2.8 3 2.1 1.4 1.4 1.9 1888 1 7 1869 1879 1889 1.3 1870 1880 1890 1.3 1871 1881 1891 1.5 1873 1882 1893 1.9 1873 1883 1893 1.3 1874 1884 1894 9 1875 1885 1895 .7 1876 1886 1896 .8 1877 1887.- 1897 .8 In opposition to the conditions prevailing in our service under condi- tions of peace, insanity would seem to be steadily on the increase in the Number of men Number of men Number of men Tear. invalided for Tear. Invalided for Tear. invalided for mental alienation. mental alienation. mental alienation. 1877 62 1883 81 1887 130 1878 94 1883 64 1888 150 1879 77 1884 73 1889 158 1880 63 1885 120 1890 192 1881 83 1886 112 846 THEORY AND PRACTICE OF MILITARY HYGIENE. French army ; the figures in the preceding table referring to French troops on home service and in Algeria. In the British army, the rates for mental disease, for the ten years 1887-96, are given as follows: Admissions Station. per 1,000 strength. England 1.3 Scotland 1.8 Ireland 1.6 Gibraltar 1 Malta 1.7 Canada 8 Admissions Station. per 1,000 strength. Bermuda 1.5 West Indies 7 Ceylon 1.3 China 1.3 Straits Settlements 1.5 India 1.7 From the above figures, it is seen that tropical service under ordinary conditions, contrary to what is commonly supposed, does not appear greatly to increase the liability to insanity. Race appears to be a strong factor in determining the occurrence of in- sanity; thus for the decade 1888-97 the admission rate in our army for this cause, per 1,000 strength, was 1.23 for white troops and but .68 for colored troops. Undoubtedly the comparatively dulled mentahty and indifference to the future which characterize the negro race has much to do with bringing about the much lower rate for insanity ia the case of the latter, but the remarkable abstinence manifested by colored troops with respect to the use of alcoholics must not be overlooked in this connection. As bearing out the theory that individuals possessing a higher order of mental attainments and a more lively sense of responsibility are more liable to de- velop insanity, Coustan states that in the French army, for the period 1891-94, the admissions for this cause, per 1,000 strength, were .80 for commissioned ofiBcers and but .31 for non-commissioned officers. For the same period he found the admission rate for privates having more than one year's service to be .39, while for those having less than one year's service it was .53. This increased liability to mental disease among recruits is undoubtedly due to the fact that in the French army, maintained by forced military service, many young men are separated from home and friends against their wish and thus become subjects of intense mental depression. Further, the most careful physical examination may overlook a tendency to mental instability in a recruit, which may afterward be quickly developed under the conditions of military discipline, the monot- ony of garrison life- or the excitement of campaign. The military spirit, which naturally cultivates indifference to life, is undoubtedly favorable to self-destruction, and does much to raise the rates for suicide in the mOitary service above those prevailing in civil life. In addition to this feeling, the soldier, constantly under the control of an- other, separated from home and friends, often occupying isolated and lonely stations and performing monotonous duties, is more prone to melan- cholia and mental depression and the tendency toward desertion or suicide occurring therefrom. In the United States service, since the Civil War, the rate for suicide increased considerably until within the last six years ; during which time there has been a sudden and great diminution. For various years, the rates have been as follows : HABITS OF THE SOLDIER AS AFFECTING EFFICIENCY. 847 Tear. 1868, 1872. 1878. 1883. Suicides per 1,000 strenpfth. , . 0.44 .. .51 , . .63 . . 1.10 1889. 1894. 1896. 1897.. Suicides I per 1,000 strengtb. . 0.83 . .79 . .43 . .39 In 1898, a year of war, the rate greatly diminished; being only .26 per 1,000 strength. This reduction in rates shows the influence of the excitement and novelty of field service in preventing a tendency to self- destruction. This fact has been noted in other armies; thus out of 401 consecutive suicides in the French army, not a single one occurred during the month of September, when the annual manceuvers are carried on. The desirability of furnishing sufficient and agreeable mental occupation for troops is thus emphasized. The suicides in our service, for the seven years 1887-93, amounted to a total of 134 cases — 7 officers and 127 enlisted men. These were divided, according to branch of service, as follows : Infantry 64 Cavalry 28 Artillery 15 Ordnance 5 Engineers 2 Medical and Hospital Corps ... 7 All others 13 Of these suicides, 51 were under 30 years of age, 56 were between 30 and 40, and 27 were over 40. The methods of self-destruction employed were : Gunshot 97 Poison 26 Drowning 4 Throat-cutting 3 and 1 each by severing radial artery, suffocation, strangulation and crush- ing by raihoad train. In 37 instances, the causes were undetermined; in the others, the reputed causes were as follows : " Alcoholism 42 Despondency 12 Insanity 10 Love troubles 6 Temporary mental aberration. . 5 Fear of court-martial 5 Domestic troubles 3 Fear of results of syphilis 2 Losses by gambling 2 Charge of theft 3 Jealousy 2 Home-sickness Nervous depression Failure to obtain promotion. . . . Tired of living Distaste for service For the four years 1894-97, only 3 of the 58 suicides reported occurred in the first year of enlistment; thus corroborating the belief that self- destruction prevails chiefly among old soldiers — among whom the rates for alcoholism are also disproportionately high. It is obvious that in our army, recruited by volimtary enlistment and for comparatively short terms of duty, the suicides resulting from dislike of the service or other reasons depending upon a military life are much less frequent than in foreign armies maiotained by compulsory enrollment. According to Millard, the rate per 1,000 for suicides in the entire Brit- ish army, during the period 1852-56, was .155; for the period 1859- 66, the rate was .26; in 1866-70, it was .443. In 1873" it had fallen to .25. For the British troops on the home stations, the rate was .23 in 1897, .21 LQ 1896 and .20 as an average for the preceding ten years. For stations outside the United Kingdom, these latter rates were practically 848 THEOEY A^B PKACTICE OF MILITAEY HYGIENE. doubled. In most cases, the causes of suicide were stated to be unknown ; in others, they are variously reported as hypochondriasis, disappointment in love, excessive drinking, dislike of the service, fear of punishment, insanity following diseases like malaria and typhoid fever, and " temporary insanity." The chief methods selected for self-destruction, in order of preference, were shooting, hanging, drowning and throat-cutting. A number of years ago, suicides were so frequent among the British troops at certain stations as to give rise to much concern and cause the adoption of measures for its repression. Thus Davy states that where three suicides occurred in succession in a regiment stationed at Malta, the body of the last suicide was officially disgraced, being dragged around the barrack- yard by an ass in the presence of the troops and then buried in unconse- crated ground. The effect of this procedure was not known, as the regi- ment was shortly removed to another station. The same writer, speaking of the conditions existing at that time, says : " It is mostly on foreign sta- tions that suicides are committed, and chiefly on islands from which there is no escape. In other stations where there are opportunities for desertion, the latter is the prevailing offence rather than suicide." Among the French troops serving at the home stations, the rate for suicide, as given by Viry, was .47 for the period 1862-69 and .29 for the years 1872-90. In a study of 69 cases, 9 of which occurred in sergeants, Arnould divided the causes as follows : Pear of punishment 21 Mental alienation from disease, 13 Unknown 12 Disappointment in love 9 Hypochondriasis 8 Alcoholism 6 Viry states that only one-sixteenth of the suicides among French soldiers are attributed to dislike of the service — ^the greater number being due to the fear of punishment,* brought about by neglect of duty and not by the severity of discipline. In Algeria and Tunis, for the period 1872-90, the suicide rate was .68 per 1,000. As is the case with insanity, suicides in the French army are influenced in their frequency by rank and length of service. Thus for the period 1891-94, the respective rates for suicide, per thousand of each class, were as follows : Ilank and service. Non-commissioned ofiBcers Privates of more than one year's service.. Privates of less than one year's service . . Rate per thousand. .23 .36 It is thus seen that where compulsory military service is required, the rates as regards the suicide of old soldiers are reversed as compared with those for our own army. In the Oran expedition of Bugeaud, in Algeria, a large number of the men who fell from the ranks, overcome by heat and exhaus- tion, are stated to have committed suicide. In the Prussian army, for the period 1829-38, Baudin states that the suicides averaged .50 per 1,000 strength. From 1846 to 1873, the rate was .46; from 1867-72 it was .60. For the entire German army, 1873-78, the rate was .61 and from 1878-88 it was .67 per 1,000. In 1896-97 it had fallen to .44; there being 225 suicides and 87 ineffectual attempts at self-destruction. The Saxon army-corps is said to have had an unusually high rate; the suicide rate for a long time averaging .92. HABITS OF THE SOLDIER AS AFFECTING EFFICIENCY. 849 As a whole, the rate for the German army is nearly twice as great as for the French service. In 1889-90, the proportional number of suicides in the German army, calculated for each thousand deaths from all causes, was as follows : Under one year of service 87.7 From one to two years' service 30.9 From two to three years' service 25.9 From three to four years' service ' 8.6 Four years' service and upward ■. 38.8 The causes of suicide in the German army may be roughly divided into one-third due to fear of punishment, one-half attributable to mental diseases and the remainder dependent upon disappointment from various causes and to dislike of the service. In the Austrian army, the rate for self-destruction is high — being .97 in 1870, .81 in 1873 and 1.22 for the period of 1875-87. Suicide is relatively about four timers more frequent in non-commissioned officers than in privates. Of late, the mortality from suicide represents 1.5 per cent, of the general mortality, and this rate appears to be increasing. As in the German army, more than half the suicides occur during the first year of service ; and mutilations of the index finger, middle finger and thumb of the right hand — to incapacitate for military service — are com- mon. One-third of the suicides are ascribed to dislike of the service, one-third to fear of punishment and one-third to melancholia. About 70 per cent, are accomplished by shooting and 20 per cent, by hanging. In the Italian army, 1874-89, the rate for suicide, per 1,000 strength, was .40. In 1888 it was .45 and in 1889 it was .38. Three-fourths of the cases are officially attributed to causes foreign to the military service. The rate for suicide was .24 in the Belgian army for the year 1891; in the Eussian army it was .20 for the period 1879-89; in the Spanish army, for the year 1886, it was .14. While it is obvious that all the causes of insanity and suicide among troops cannot be brought under official control, it is equally clear that the rejection or early elimination of those of unstable mental equilibrium, or with tendencies toward alcoholism, will do much to reduce the rates for these causes. This reduction is further assisted by short periods of enlistment, as is the case at present, and by tours of foreign service of not too long duration. While the unneces.sary severity of discipline which is maintained in foreign armies does not obtaia in our own service, it should not be forgotten that intelligent and just administration by superior officers wiU do much to promote the mental as well as the physical welfare of the men over whom they have been placed in power. The contented soldier has no leaning toward melancholia or to self-destruction. 54 CHAPTER XVIII. THE HYGIENE OF HOT AND COLD CLIMATES. General Consideration of Climate. — The primary cause of climate is the solar action — this being regulated by the distance from the equator, the angle at which the sun's rays strike the earth, the length of the day, and the degree of refraction which the rays undergo in their passage through the air. The secondary causes of climate are the elevation of the land, the influence of the sea, winds, rainfall, storms and moisture, the nature of the soil, the general and local inclination of the place, the configuration of surface, the amount of vegetation and extent of cultivation, the internal temperature of the earth, the purity and electrical state of the atmosphere. According to Cullimore, the influence of temperature upon health, as shown by the relative duration of life in the different climatic zones, is as follows : From the equator to the 20th degree of latitude there is 1 death annually to each 25 inhabitants; from the 20th to the 50th degree of lati- tude, 1 death to 35 ; from the 40th to 60th degree of latitude, 1 death to 43; from the 60th to 80th degree of latitude 1 death in 50. In the north of France there is one death to each 43-44 inhabitants ; in the south, 1 in each 40 of the population. Smith states, with reference to this point : "It is a well established fact that a temperature of 54° F. is best adapted to the public health, for at that temperature the decomposition of animal and vegetable matter is slight and normal temperature is easily main- tained." The influence of elevation of land is second only to that of the sim, as measured in degrees of latitude from the equator, in its effects upon the character of a climate, as it renders tolerable many regions in the torrid zone otherwise uninhabitable by the white race. Plains are subject to great difference in temperature between night and day, and plateaus to extremes of heat and moisture ; but isolated, flat-topped hiUs and hilly dis- tricts are more equable. Mountain ranges exercise a marked influence on climate ; their windward and rainy sides being often deluged with rain, while the country beyond is dry and protected. In passing over the sum- mit of a mountain range, winds blow in a slanting direction down the lee- ward side, becoming drier and more heated as they descend. The dis- tance at which they again reach the gi'ound is said to average about seventy times the height of the range over which the wind has passed. The climate of valleys is influenced by the character of their inlets and outlets, their breadth and height, the slope and vegetation of the surround- ing hUls, the amount of simshine which they enjoy, and the protection afforded from cold or hot winds. In broad valleys, the heat during the day may be great, owing to reflection from the mountain sides; while the nights are cool, owing to rapid radiation and to the movement down- THE HYGIENE OV HOT AND COLD CLIMATES. 851 ward of cold currents of air from the hiUs. Narrow valleys are more equable as to temperature, but are apt to be damp, misty and lacking in sunshine. The influence of the sea is next to that of elevation of the land in modifying climate. It is owing to the immense preponderance of water over land that the average temperature of the southern hemisphere is three degrees lower than the northern, that the climate of high seas is so cool and equable, that small tropical islands approaching in character to the climate of high seas are generally more healthful than larger ones, and may be more capable of colonization by the white race. In hot climates, the maritime regions are never as warm as the interior of the country at the same level, but in cold countries the reverse is the case. In cold climates, also, the temperature of the coast is often increased by warm ocean currents ; while, on the other hand, cold currents also exist and lower the tempera- tm-e of hot regions. The effect of the sea is thus to equalize temperature ; the seasonal difference and that between day and night being less on the coast than at inland situations, while the relative humidity is generally great, and hot, dry and dusty winds rarely occm-. The absence of cold winds depends mainly on the level character of the land. Marine climates are also cooler than those of other places at the same level, in consequence of the local wind, owing to the vmequal heating of the land by day and night, while the greater humidity of the air helps to veil the rays of the sun. Water is heated more slowly, and gives off heat more slowly, than does land. It also retains it longer, and the loss by radiation is less than from land, while the air over it is more moist and equable than else- where. The specific heat of water is about five times that of earth ; water cooled at the surface sinks, allowing a lighter and warmer stratum to come to the top — hence the adjacent layer of air is not cooled at night to the extent that it is on land. Wind may be defined as the movement of the air, resulting from the difference in its temperature at various places. Heated air rises, and that which is of greater density ilows in to supply its place. In their effects on health, winds are considered with reference to their velocity, temperature and the amoimt of dust or aqueous vapor they carry. The greater the rapidity of then- movement, the more chilling and forcible their effect. Even hot winds, if dry, generally cool by promoting evaporation; but if moist they have proportionately little effect in lowering the temperature. The rainfall depends on the prevailing winds, as regards their direction, temperatm-e, moisture, velocity and electric state. Clouds deposit their contents either through the influence of cold or as the result of concussion or compression. Hence it is that the rainfall is greatest on the slopes of mountains, where a hot and moist air often first comes in contact with a cold one. Next to that on mountains, the rainfall is heaviest near the sea. The average amount of precipitation decreases from the equator to the poles ; while as regards the number of rainy days, except in the vicinity of the equator itself, the reverse is the case. The rains are periodical in the tropics and the summer is the rainy season, while the greatest rainfall occurs in winter in sub-tropical regions. In temperate climates the rains occui' throughout the year; but the heaviest fall is in autumn, when the warm sea-winds first meet the earth, whiclf at this season is beginning to 852 THEORY A^T) PEACTICE OF MILITARY HYGIENE. grow cool. The rainfall on the slopes of hills increases with height up to great elevations ; but at the altitude of ten thousand feet it is generally slight, snow usually taking its place. The so-called rainless regions, where the winds blow constantly toward the sea, are usually excessively hot and comprise the barren wastes known as deserts. Owing to their size, small islands of level character offer no obstruction to winds which blow over them, and the rainfall is similar to that of the surrounding seas; while forests, on the contrary, by offering a certain obstruction, cause an increased precipitation all around the coasts, with less in the interior — and this is in confirmation with the general effect of forests, which is to increase the precipitation of rain in the region surrounding them. While the princi- pal source of moisture is the rainfall, rainy regions may be fairly dry as regards the state of the air, owing to the heat of the sun, the small number of wet days, the porous nature of the soil and, on mountains, the inferior, capacity of the air for retaining moisture. On the other hand, the absence of rain is sometimes compatible with considerable atmospheric humidity, through the lack of condensing currents of cold air. Under such conditions, fogs and dews may supply to some extent the want of rain. The amount of moisture is represented by the degree of humidity, which is described as absolute and relative. The latter is more important from a climatic point of view. It represents the ratio between the amount of humidity in a given quantity of air and the amount the air can carry without the production of rain, and must be considered in connection with the temperature, the density of the aii- and its evaporating power, the latter being greater as the temperature is higher. It decreases with the ascent of mountains, is generally considerable over bodies of water, in- creases from the poles to the equator and is greatest of aU in the tropics during the wet seasons. Moisture lessens evaporation from the skin and lungs, and, if the air is still, may help indirectly to increase temperature through its power of absorbing heat. If not accompanied by wind or rain, moist hot climates are more oppressive than the combination of heat and dryness. If the former conditions prevail, and the sky is overcast, the feeling even in hot countries is that of chilliness. Dry air is every- where more bracing; moist air more soothing, enervating and more fre- quently showing its effects in loss of appetite, depression of spirits and disorders of the kidneys, stomach and bowels. Storms are felt to the great- est degree near the mountains and along the seashore — at the changes of the seasons they are most violent in the tropics. and sometimes dangerous to the sickly. Atmospheric electricity probably exercises considerable influ- ence on the human organism, but present imperfect knowledge does not justify any definite conclusions as to its effect. A marked influence on the temperatiu'e and salubrity of a locality is exercised by its geological formation. In the tropics, it will generally be found that in places of moderate elevation the soil is composed of volcanic debris, covered with humus. This soil is comparatively healthy. In hot cUmates, a sandy soil is the most disagreeable of all; sand being not only easily heated but retaining a high temperature longer than any soil. The effect of cultivation and moderate afforestation is generally greatly to im- prove the climate of a place and to render it more equable. The tempera- ture of the soil in forests is about twenty per cent, lower than that out- THE HYGIENE OF HOT AND COLD CLIMATES. 853 side, and the mean annual temperature of the air ten per cent, lower. The day temperature is also lower, that of the night higher. The relative humidity is increased from three to ten per cent., and the rainfall is also greater. The air over grassy land is cooler and moister than over barren or sandy soil; while that over marshes is not only colder and. damper than in other situations, but is generally saturated at night and morning with mist and fog. Drainage raises the temperature of the soil of arable and pasture-land ; and the greater healthfulness of drained land is perhaps due, to some extent, to the soil-temperature being less subject to fluctuations. As to climate, that of the equatorial belt is characterized by great equa- bility, almost daily rains, cloudy skies and constant heat. The white race cannot become acclimated at lower levels near the equator; and the moxmtain resorts, unless very high and dry, afford no adequate change on account of the absence of seasons, the heavy rains and the excessive atmos- pheric rarefaction dependent upon the combined effects of heat and elevation. In the tropical region extending from the equatorial belt to the 23rd degree of latitude, the hot and cold seasons become gradually more marked ; until near the tropics, while the summer heat is intense, the cold of winter is perceptible and restorative. Here the hot and dry season is in the spring, the wet in summer and the cool in autumn and winter. In the dry, hot season — particularly in fairly dry climates — the heat before the rains is often almost intolerable, yet this period is perhaps the healthiest portion of the year. Like the equatorial belt, this region is characterized by marshes, jungles and great unhealthiness, especially for the white race and for new-comers. Some localities are rendered additionally insalubrious by the presence of malarial fevers, from which the drier regions are com- paratively free. In the sub-tropical division, the mean annual temperature is said to be eighteen degrees lower than that for the torrid zone. The variations are greater, and all the meteorological phenomena less uniform. Warm weather still predominates, yet there is a distinct winter and the seasons of spring and autumn begin to be apparent. When near the tropics, these regions are usually subject to the diseases of the torrid zone; but when well drained and cultivated, and lying toward the temperate regions, they are generally healthy. Temperate climates are characterized by great variability as compared with the uniformity of the polar and tropical divisions. The fluctuations are frequent, and the mean annual oscillations of temperature vary from 40" to 70° F., depending greatly upon local conditions. The daily varia- tions are also frequent, and all the seasons are distinct and nearly of equal duration. The spring and autumn, although agreeable, are the most un- healthy and the most subject to climatic disturbance. The winds are variable, whUe the rains, though less abimdant and regular than in the tropics, are far more frequent and evenly distributed through the year. The rate of mortality is lower, and the longevity and intellectual and physical standard higher, than in warmer regions. Cold climates, which represent the polar extremities of the great tem- perate zones, are characterized by a short but brilliant summer, and by a winter with snow on the ground between the months of October and May. The diurnal range, owing to the long duration of the summer sunny days 854 THEORY AND PRACTICE OF MILITARY HYGIENE. and to the slight influence of the sun iu the winter, is remarkably slight, and contributes materially, in spite of the chilling mists and fogs, to that comparative freedom from chest affections which cold climates enjoy. Such climates are perhaps the healthiest of all. Arctic regions are divided into the coast and inland ice districts. The climate is extremely cold, as the summer begins with July and ends with August. During this period, the sun remains continually above the horizon. Rain, sleet and snow occupy the spring and autumn. In- addi- tion to the intense cold, sudden changes are of frequent occurrence, summer simshine giving place to fogs, mists and snow. The mean temperature of South Greenland is 33° F. At Upemavik, the mean of summer is said to be 58° F. and that of winter — 7° F. Snow faUs to the depth of twenty feet in certain localities. The climate is not imhealthy ; the most common diseases being frost-bite, scurvy, the eruptive diseases, contagious skin affections and ophthalmia. I. THE HYGIENE OF HOT CLIMATES. The physical elements of a tropical climate, ranged according to their hygienic importance, are humidity, heat and lack of variety. Humidity, in temperate regions, generally goes with cool weather, but within the tropics great heat prevails when loss of heat through evaporation of per- spiration is retarded by a high degree of atmospheric moisture ; dry heat, even if prolonged and of considerable degree, is by no means as unfavor- able to the human organism. Everything which conduces to give variety to climate in the tropics affords relief. The alternating sea and land breezes of islands are potent forces in increasing their salubrity, and this is especially so when such islands are volcanic or mountainous. Hot climates exert an unfavorable influence on new-comers through two conditions, those which are meteorological and those which result from endemic diseases — the latter being more directly dangerous. There is, however, ample proof that tropical heat and himiidity produce marked changes in body-function which exert an effect adverse to the health and existence of all but the native-born. A brief consideration of these alterations of body function is important in connection with the considera- tion of various problems in tropical hygiene, particularly in relation to food and the processes of metabolism. Physiology of Hot Climates. — The body -temperature in the tropics is appreciably elevated above the normal in new arrivals. Rattray, in his investigations upon this point, obtained the following results : Hour of day. Temperate climate, near England ; temperature, 65° F.; average of ten days. Tropics generally ; average of flfty-one days. Equator, temperature, M° F.; average of seven days. 9 A.M Q8.V 98.3 98.5 98.51° 99 98.47 98 .'i 3 p. >r 9 P.M 99.5 99.1 98.3° 98.66° 99.02° THE HYGIENE OF HOT AND COLD CLIMATES. 855 Maurel found an increase of body-heat in individuals recently arrived in the West Indies, ranging from .5° to .9° F. ; and Jousset noted an average increase among the whites in Senegal of even greater degree. Fayrer states that among European residents in Bengal, the bodily tempera- lure is .41° F. higher than the average of healthy persons in England. Careful observations made on Europeans between Khartoum and the equator showed that for those of less than two years' residence, the body-heat aver- aged 1° F. above normal; while among such as had been in that region longer than four years, the temperature was still half a degree above normal. These facts are interesting and important, and, as subsequently advanced, may explain the greater prevalence of disease in individuals undergoing the so-called process of acclimation. In temperate climates, animal-heat is readily lost by radiation and contact with the external air, by the heating of inspired air, by exhalation of moisture in the breath and by cutaneous evaporation. In the tropics, the difference between internal and external temperature is always very slight, and it may frequently happen that for considerable periods the heat of the surrounding atmosphere may even exceed that of the body. Further, the high degree of humidity ordinarily present in the tropics opposes evaporation of moisture. It therefore hap- pens, through these changed conditions, that, instead of being concerned with the dissipation of heat, the vital forces must frequently neutralize heat-reception in order to keep the bodily temperature down to normal. This produces an alteration in metabolism and throws additional work on the kidneys and liver; for an excess of nutritive material, which in tem- perate climates would be oxidized in the production of heat, requires here to be merely excreted. Serious and unusual demands are thus made upon the excretory organs and their resistance is distinctly lowered — and in this state they are not infrequently called upon to eliminate the toxins of certain infectious diseases so common in some portions of the tropics that the stranger can scarcely hope entirely to escape them. A loss of body-weight occurs in hot countries, and the same is com- monly observed in summer in the temperate zone. Eattray noted that, with an average temperature of 80° F., the loss of weight among a body of Brit- ish marines averaged eleven pounds per man during the period of one year. The decrease was greater when salt provisions were given and the air was loaded with moisture ; the loss of weight when hard labor was required being even greater and more rapid. In the dry season forty-four per cent. , and in the wet season seventy-six per cent., of the individuals observed by him lost in weight. Eattray concluded that this effect was due to the destructive in- fluence of prolonged heat upon the cellular elements of the organism, together with imperfect oxygenation. Adipose tissue, as a non-conducting layer, is undoubtedly potent in conserving internal heat and diminishing the effect of outside low temperature. In cold regions, the proportion of fat normally present in the organism is much greater than in warm climates, where the storing up of fats in human tissue is rare, and even the artificial fattening of animals is accomplished with the greatest difficulty. In cold climates, on the contrary, considerable deposition of fatty material* is the rule. The animal flesh of the far north, as seal, bear and walrus meat, is notoriously rich in fats ; while the chief protection of the whale against the cold of the polar seas is the thick layer of blubber in which the muscular structure 856 THEORY AND PEACTICE OF MILITARY HYGIENE. is enveloped. Viewed from this standpoint, the decrease of body-fat which occurs in the tropics may be looked upon as one of the most important processes by which the adaptation of the organism to changed conditions of temperature, through better dissipation of body-heat, is accomplished. The discomfort of the obese during warm weather is proverbial ; and hencP loss of weight, provided the decrease is strictly limited to adipose tissue, may be regarded as wholly beneficial. It is obvious that any excess of food above the nutritive requirements of the organism, which in temperate climates is largely converted into systemic fat, cannot be devoted to this purpose in the tropics with either facility or advantage. Tropical heat directly lowers the pulse-rate ; Eattray finding that the average rate of cardiac action in the tropics was less by two and one-half beats per minute than in the temperate zone. The following results were obtained by him : Hour. Number of observations. Tropics. Tempekate Zone. Lowest. Highest. Range. Average. Average. 9 A.M - 53 53 49 66 68 73 113 108 110 46 42 37 86.4 88.8 87.3 91.7 3 P.M 88.1 9p.m 90.5 87.5 90.1 This reduction of the pulse-rate is doubtless related to the diminished respiratory function.; and further observation proves what the latter fact suggests — ^namely, that in the tropics the pulse is diminished not only in frequency but in force. The low arterial tension always noted in hot climates is a direct result of loss of fluid through increased perspiration, favored by a relaxed state of the capillaries. The first effect of tropical heat is to increase the respiratory capacity. This has been shown by Eattray by means of the spirometer; his obser- vations being subsequently confirmed by others. The results obtained by this investigator are as follows : Average capacity of chest In cubic Inches. Temperate zone near England, at sea — June. Thermometer 65° F. Hygrometer 3.5° F ■ 256.083 Tropics, at sea— July. Thermometer 78° F. Hygrometer 4° F 280.75 Tropics, at sea — August. Thermometer 83° F. Hygrometer 4° F. .. . 287.416 Temperate zone near England, at sea — September. Thermometer 65° F. Hygrometer 1.5° P 360.35 Temperate zone, England — February. Thermometer 43° F. Hygrom- eter 3° F 353.737 The average gain in lung-capacity noted by him for the tropics was 31.4163 cubic inches; the percentage of gain, as compared with the temperate zone, amountingto 12.24 per cent. CuUimore, however, states that this increase in lung-capacity does not continue, and that, after a period ranging from six months to tw» years, it falls below the level for Europe. Closely allied to the foregoing is the influence of tropical climate on the frequency of respiration. In heated au--chambers, the rate of respira- tion becomes leos in man, and Vierordt and Ludwig long since found that THE HYGIENE OF HOT AND COLD CLIMATES. 857 the same results were obtained in animals subjected to great heat. Eat- tray's observations as to the comparative frequency of respirations ia hot and cool climates are as follows : Temperate zone . . Tropics England in summer — June. England in winter — February. Equatorial doldrums, outward voyage. Equatorial doldrums, return voyage. a . m t., O « = § Hi < 63° 18 13.5 43.25° 17.5 15 78.74° 14.5 11 78.6° 15 12 aj o g §■23 15.68 16.5 13.74 13.74 Not only is the respiratory action markedly decreased in hot climates, but the greater quantity of air taken in at each inspiration in the tropics does not make up for the diminished number of respirations in supplying the same amount of oxygen to the blood as in cold climates. Using the above data, Eattray calculated the deficiency in the oxygen inspired in the tropics to be as follows : CUmate. Cubic inches in each Inspiration. Number of inspirations per minute. Cubic inches respired. England Tropics . 15.000 16.836 17 14 355.000 335.704 Diiference in favor of a temperate climate, 19.396 cubic inches, or 7.567 per cent. "This decrease of 7.567 per cent, in the quantity of air respired daily, diminishes the quantity of carbon which the lungs in ordinary circumstances can throw off in the tropics by .7567 ounce; 10 ounces being taken as the average amount thrown off in temperate climates will give 9.243 ounces as the amount for the tropics. But as tropica^ air contains less oxygen for a given bulk than air of colder latitudes, through the expansion of gases by heat, the decarbonizing capabilities of the lungs in tropical latitudes will evidently be still further curtailed and the amount of carbon they can throw off considerably decreased. Air increases by ^^ its volume for every Fahrenheit degree of heat, and the difference between the temper- atures in which these experiments were carried on being 18° F. (65° and 83° F.), if we reduce the amoimt inspired in the tropics by a -^^ part, this will give its equivalent bulk in the temperate zone, thus : 835.704 205/704 l+TirX 18 "1.0375 237.1846 cubic inches, which is equal to a decrease of 8.5194 cubic inches, or 3.614 percent. Then 255 minus 227.1846 cubic inches give 27.8154 cubic inches per minute, or 1,668.924 cubic inches per hour, or 40,054.176 cubic inches per day = 10.907 per cent, as the grand total difference in favor of a temper- ate climate, after deducting the real increase in volume and correcting for expansion of heat. By again reducing the 9.243 ounces of carbon by 3.614 per cent., or .33409 ounce, we get 8.909 ounces as the total amount 858 THEORY AND PRACTICE OF MILITARY HYGIENE. which the kings throw off in the tropics, the difference between the tropical and extra- tropical qualities being 1.1028 ounces." The explanation of the variation in respiratory capacity, noted above, would appear to be due to the fact that there is no actual increase for the tropics in the size of the chest and enclosed lungs, but only an alteration in the relative proportion of blood and air contained in the latter. The bulk of the lungs remaining the same in the tropics as in cold latitudes, or being, as shown by Parkes, even somewhat diminished from their compar- ative abeyance as excreting and heat-generating organs, the blood, diverted to the functionally excited and congested skin and liver, permits the in- gress of a larger quantity of air into the pulmonary air-cell^. With the diminution in arterial tension there is, also, at each respira- tory movement, less blood forced through the lungs than in the temperate climate, and this diminution necessarily implies a lessened value to the respiratory act. Further, the air in the tropics is rarefied, and pressure, which rules the conditions of pulmonary endosmosis, is diminished ; hence it may be that the air reaches the pulmonary alveoles under pressure in- sufficient properly to force it into the pulmonary capillaries. The defi- ciency of oxygen taken into the organism in the tropics, as influenced by the above factors, may therefore be considered to be made up approximately as follows : Lessened value of respiratory act 7. 5 per cent. Rarefaction of air 3.6 " Diminished cardiac, action 3 " Decreased air pressure 2.2 " Total 16.3 " It is undoubtedly true that less oxygen is requued by the organism in the high temperatures of the tropics. Through decreased exertion, a smaller amount is required for the metamorphosis of waste particles, and, where lessened necessity and desire for food diminish the ingesta, less is required for direct combinat^n with the nutritive elements in the produc- tion of energy. It is probable, however, that there is a somewhat in- creased absorption of oxygen in hot climates by the functionally excited skrQ, which may, to a slight degree, act vicariously as a respiratory organ and so lessen the amount required by the lungs. Furthermore, the skin is aided in relieving the lungs, in the decarbonizing process, by the function- ally excited liver and kidneys, which eliminate carbon in forms which do not require much oxygen for their formation, namely, as bile and uric acid. Where the blood does not obtain a proper supply of oxygen, its vital properties are diminished ; a fact soon apparent in the deficient nutrition of the organism, and the depraved condition by which not only is liability to disease increased but also the probability of a fatal termination should disease occur. Deficient oxygenation, combined with heat, exerts a directly deteriorating influence on the blood corpuscles. CuUimore states that the blood corpuscles frequently diminish to as low as 3,000,000 per cubic mil- limeter after long sojourn in the tropics, and that the quantity of haemo- globin is also much decreased. Every resident in the tropics early becomes antemic ; the heat often being assisted by malarial influences in deteriorat- ing the function and diminishing the number of red blood corpuscles THE HYGIENE OF HOT AND COLD CLIMATES. 859 The amount of sweat is greatly increased. Fonssagrives states that it is double the average amount secreted in Europe, often amounting to four or five pounds in the twenty-four hours. The amount of solids elimiuated in this manner, however, is not proportionately increased. In addition, the secretion of sebum is more abundant than in temperate climates. In this connection. Hill says : " There are certain peculiarities iu the natives of Eu- ropean countries that must strike the pathologist as intimately connected with the nature and treatment of diseases. These are chiefly the complex- ion of the skin, the large development of the respiratory and biliary, nervous and circulating organs, compared with the natives of intertropical coimtries. The skia of the dark races is not only different iu color, but it is also con- siderably modified in t&ture, so as to enable it to perform a greater extent of function than the more delicately formed skia of the white variety of the species. The thick dark rete mucosum of the former is evidently more suited to the warm and moist climates of the tropics than that with which the latter variety is provided. The skin of the negro is a much more active organ of depuration than that of the white. It not merely exhales a larger proportion of aqueous fluid and carbonic acid from the blood, but it also elaborates a more unctuous secretion, which by its abundance and sensible properties evidently possesses a considerable influence in counteracting the heatiag effects of the sun's rays upon the body, and in carrying off the superabundant caloric. While the active functions thus tend to diminish the heat of the body and prevent its excessive increase by the temperature of the climate, the materials that require removal from the blood are elimi- nated by this surface, which in the negro especially performs excreting functions, very evidently in aid of those of respiration and of bihary secre- tion. In the white variety of the species, on the other hand, the functions of the lungs and liver are much more active than in the darker races, changes to a greater extent being performed by respiration in the former than the latter. The liver is also larger and its secretion more copious in the European than in the African or Asiatic." When the air is dry and in a highly electrical condition, skin action is greatly facilitated. It then becomes a refrigerating apparatus of remarkable power, being sufficient to protect the organism against the highest temperature. As a result of increased perspiration, there is a diminished excretion of urine, the reduction amounting to about one-third of the usual amount in temperate climates. Mourson states that the diminution in the output of urea usually amounts to about ten or fifteen per cent. According to Eijk- man, Europeans who had been in Java from two to six months excreted an average of 14.8 gm. of nitrogen daily, or .226 gm. per kilogram of body-weight, while those who had lived in the tropics one and one-half to fifteen years excreted an average of 12.802 gm. of nitrogen daUy, or .193 gm. per kilogram of body-weight. Such decrease in eliminatory function on the part of the kidneys, according to Moore, is followed by increased secretory action of the liver, whereby some effete matter is passed into the intestines with the bUe. But increased liver action is accompanied by congestion, and constant congestion frequently by hepatic deposit and degeneration, with impairment of function. Through the loss of fluid resulting from increased perspiration, there is a diminution in the secretion of saliva, mucus, the gastric and pancreatic 860 THEORY AND PRACTICE OP MILITARY HYGIENE. juices and the bile. As a consequence, also, there is dryness of the throat and fauces and exaggeration of thirst, weakness of appetite, impaired diges- tion, gastric fullness after eating and habitual constipation ; these, accord- ing to Nielly, berag digestive phenomena constantly observed iu the tropics. The increased loss of fluid causes a corresponding thirst, and the resulting increased ingestion of fluids by the new arrival is without doubt a cause for sickness, since it dilutes the gastric juice, impairs digestion and favors diarrhoea. In addition, the change of diet necessitated by residence in the tropics, together with the presence of imaccustomed forms of bacteria, is prone to cause a certain amount of gastro-intestinal disturbance even in the most careful individuals. Upon the nervous system, a marked effect is exerted by heat and moist- ure, and a depression of vital and nervous energy is induced far exceeding that ordinarily observed in temperate climates. The brain suffers with the system in general — it would appear to more than its proper proportion. Certain it is that, in the tropics, persons even in fair bodily health find themselves, so far as intellectual work is concerned, at a very low ebb ; soon wearied, fagged and unable to concentrate their ordinary amount of brain- power on any one subject. This diminution in capacity for mental labor is often followed by reduced powers of memory and is usually accompanied by nervousness and irritability. Acclimation. — ^According to Eochoux, the process of acclimation con- sists in ''a profound change in the organism, produced by a prolonged so- journ in a place where climate is widely different to that to which one is accustomed and which has the effect of rendering the individual who has been subjected to it similar in many respects to the natives of the country which he has adopted "• — and Aitken, who quotes this observation, supple- ments it by saying : " The process takes place to a certain extent, so far as some individuals are concerned, but the ability to become acclimated is not possessed to the same extent by aU nations." That residence in hot climates, under the circumstances of ordinary life, has an adverse effect on the white race cannot be doubted. Some consti- tutions seem to be altogether unfitted for undergoing high temperature and great humidity, and such individuals lose their health and physical energy from the moment of their arrival in the tropics^. A still larger number do so sooner or later under a more protracted residence, even if they escape being attacked by the endemic or epidemic diseases incidental to such climates — and hence the question of acclimation assumes great practical importance from the military standpoint. As compared with whites, the African and Asiatic races possess a rela- tive immunity to many diseases common in low latitudes, and an admix- ture of such blood confers an undoubted resistance to the prejudicial ef- fects of a hot climate. It is a matter of common knowledge that the half-castes of such races, brought to the tropics, are often able to survive without difficulty in regions inimical to occupancy by white men. The fact seems to be well established that, among whites, Semitic peoples possess a power of acclimatioD|or adaptability to tropical climates superior to that enjoyed by the Aryan races ; and among the latter the inhabitants of southern countries — the Spaniards, Portuguese, Maltese and Sicilians — are superior in this respect to those of the north. Next to the Jews, the gyp- THE HYGIENE OF HOT AND COLD CLIMATES. 861 sies are probably the most cosmopoKtan. In the French expeditions in the tropics, the zouaves and troops with an admixture of Arab blood and — in less degree — the troops coming from southern France, have suffered less from typhoid and other forms of fever than have those from the north. The Anglo-Saxon branch of the Teutonic stock is severely handicapped by nature in the struggle to colonize the tropics; and Eipley gives the follow- ing table as showing the relative disabilities of Europeans in Algeria, on this point, for the years 1855-56. Births per 1,000 population. Deaths per 1,000 population. Spaniards 46 44 39 41 31 30 Maltese 30 Italians 38 French 43 Germans 56 It is not at all easy to say, however, how much of the excess of mortality of Europeans in tropical and sub-tropical countries, over that of the natives, is simply attributable to climate ^er se and is consequently inevitable, or how much of it is the direct consequence of unsuitable habits of life and of the neglect of sanitary laws and of personal hygiene. It may be said, in general, that the only real acclimation in warm countries is that which en- ables the white race to enjoy health equal to that of the natives, while con- stantly performing hard manual labor in the open an- — and this is not considered possible by most authorities. It cannot be denied that the Spanish nation— in which, it should be mentioned, there is a considerable element of Moorish blood — ^has met with a certain degree of success in colonizing tropical countries ; but this has not been as an agricultural class, and it is none the less true that it is the only white nation which has suc- ceeded to any degree in establishing a foothold in the tropics. In India, it is an axiom that English stock cannot exist beyond the third generation. The new arrival in the tropics is usually condemned to undergo certain diseases prevalent in such climates, and if these are not fatal a certain de- gree of tolerance to altered atmospheric or other influences, in a fair pro- portion of cases, is imdoubtedly acquired ; but that this latter class, at any portion of its existence, possesses the immunity to tropical disease which is so marked a characteristic of the natives must be denied. The attempt at the acclimation of the white race in the torrid zone is a procedure fraught with, difficulty and danger and is usually compromised by unfavor- able endemic influences. Experiment has demonstrated that in animals there is a definite connection between an elevated body temperature and the liability to disease of an infectious character. Whether this accounts for the greater susceptibility to disease existing in unacclimated individuals in the tropics is an open question ; but it is certain that strangers are most liable to sickness during the period immediately following their arrival, when their temperature is above the native normal. As far back as 1788, Hunter wrote : " Those who are just arrived from cool and healthy climates are particularly subject to fevers, as is daily experienced by all new-comers. A regiment always loses a greater proportion of men in the first year than afterward, supposing their fitness to be the same." This point is well lEus- 862 THEORY AND PEACTICE OF MILITAEY HYGIENE. trated by Marston in the following table, showing the death rate of British white troops in India, per thousand of each class, for different periods of residence in that country, based upon statisics for the period 1877-84. Tear. First and second years of service. Third to sixth years of service, inclusive. Seventh to tenth years of service, inclusive. 1877 3.31 7.90 7.99 9.08 4.55 4.68 4.98 5.47 1.35 2.64 2.18 1.78 2.07 1.93 1.55 1.55 90 1878 1 38 1879 1 24 1880 .47 1881 56 1882 34 1883 .55 1884 46 All authorities agree that the regions of the tropics where acclimation of the white race is most difficult of accomplishment are to be found in the areas of excessive humidity. Hence any alleged successful examples of tropical colonisation should always be examined in the light of this con- dition. Wherever there are perceptible seasons of heat and cold, the ad- justment of the organism of the foreigner to a new environment is more readily accomplished; and this is one advantage of the climate of tropical plateaus, where both daily and seasonal variations of temperature are com- paratively great. It has repeatedly been demonstrated that most attempts at gradual ac- climation are futile, except as regards the season for arrival, and do not serve to protect against the endemic diseases of the tropics ; particularly in the case of malaria there being no such thing as an acquired immimity. It is best, therefore, to send troops direct to their post of duty from a tem- perate station. Where new troops are destined for an extremely unhealth- ful locality they may, however, on landing, be sent for a brief period to a high and salubrious station to become partially accustomed to new condi- tions of climate and environment. Composition of Military Forces. — From what has just been said, it is evident that troops detailed to the tropics should, for the United States ser- vice, be as far as possible recruited in the southern states, and particularly from those bordering on the Gulf of Mexico. A large proportion of such forces win with advantage be recruited from the negro population of these warmer districts — it being well demonstrated that the negro enlisted from the northern states has, through his environment, largely lost his racial insuscep- tibility to typhoid, malarial and yellow fevers. It will also be of the utmost advantage to organize a considerable proportion of the troops required for colonial service from the accHmated natives of the region within which military forces must be maintained. This policy is largely employed by England, France and Germany ; the French colonial forces being said to be made up of 18,000 white troops and 16,000 natives. In the British military service, the native troops serving in the tropics are about two and one-half times greater in number than the Europeans ; and in the most unhealthful colonies, the proportion of native soldiers is fom-, five or — as in Sierra Leone — six times greater than that of the white troops. This ex- ample should be followed in our own service and there should certainly be THE HYGIENE OF HOT AND COLD CLIMATES. 863 a sufficient native force to garrison the more unsalubrious stations ; the re- cent organization of native regiments in the Philippines and in Porto Eico being of much advantage. Such native troops escape much of the sickness which must be regarded as inevitably attaching to foreign forces, as has al- ready been shown in connection with the diseases of the soldier, and hence their constant rate of effectiveness is higher. Concerning this point, Lemure writes: "During the active period of (French) operations in Dahomey, August to December, 1892, the rate of deaths from disease among the European troops was 111 per 1,000; among the natives 15.1 per 1,000." Speaking broadly, the nearer in physical type, temperament and com- plexion the soldiers detail*! for tropical service approach to the natives of such climates in these respects, the more likely they are to stand the climate and to prove healthier than fair-skianed men of larger stature — who, on the other hand, are far better adapted for hard and arduous work and supreme physical effort in cold or temperate regions. For service in hot climates, men of medium stature, spare frame, dark hair and complexion, and thick skins may be expected to retain their health and to make the more en- during and efficient soldiers. It is of importance that only those should be selected for such service as show no signs of actual or latent disease, have become accustomed to the conditions of the military life, and are sea- soned, mature and well developed. The filling up of regiments in the trop- ics with untrained and youthful recruits is a mistaken and wasteful policy ; and all recruits should be re-examined before embarkation with respect to their fitness for tropical service. In the French colonial service, only those men are permitted to take the field who have attained the age of twenty -two years, have been one year in the service and are of robust constitution and full-blooded habit. The commander-in-chief of the British forces in India, in 1876, officially expressed his belief that the soldier was at his best, for duty in that country, at the age of twenty-seven to thirty years of age and after five years' residence in India ; the adjutant-general being of the opin- ion that the British soldier was most fit for tropical service at the age of twenty-seven years. No soldier was accepted for the British Ashanti ex- pedition, in 1895, who was not at least twenty-three years of age and had not had as much as three years' previous military service. The vast im- portance of age and previous service in relation to sickness and mortality in the tropics has also been brought out in previous chapters, and it may be accepted as being most undesirable to send recruits under the age of twenty-four years to stations in the low latitudes. It is important that troops to be sent to the tropics should consist of weU-disciplined and not newly raised men, for the latter, being less orderly and discreet and not accustomed to the life of the soldier, suffer far more from the climatic and environmental conditions than those habituated to discipline and control. In addition, it is extremely difficult properly to drill and instruct men in a climate where there are so many opposing conditions to be encountered and where the great heat renders it impossible to exercise in the open air except for a short time in the morning or evening. Season for Arrival. — This is a matter of much importance, and the military history of every colonizing nation shows illustrations of the grave consequences which have followed neglect in this respect. In the British expeditions on the west coast of Africa, prior to 1873, the re- 864 THEORY AND PEACTICE OF MILITARY HYGIENE. suits were uniformly disastrous and the sickness and mortality little short of appalling. In the Ashanti expedition of that year, however, the oper- ations were strictly limited to the healthy season and the sickness and loss of life attained only insignificant proportions. The rainy season is much more dangerous to the unacclimated, and it is advisable, where prolonged residence in the tropics is anticipated, that the organism be in a certaiu degree prepared for the arrival of this season by a previous existence of several months under the new conditions. By such an arrangement, the suddenness of transition from a healthy climate to the most sickly season of an insalubrious one is avoided, the clothing and diet are more gradually modified, the system has a better opportunity to accommodate itself to a change of function, and the unhealthful season, when it does come, is met- by constitutions modified to such extent as to have lost something of their impressibility to endemic causes of disease. Hence, time spent in delaying the embarkation of troops to a more favorable moment is not lost, but will be more than compensated for by time saved from restrained methods of life or perhaps confinement to bed during acclimation in an unfavorable season. England and Germany have issued formal advice to intending colonists in respect to the time for arrival, and do not, except from urgent necessity, send civU or military officials to the tropics during the rainy season. This is a rational precaution which should be carefully observed in our own service, and, as far as possible, all movements of troops 'to the tropics should be so timed as to result in their arrival during the months of December and January. Food. — ^With respect to the quantity of food necessary to the mainte- nance of health and vigor ia the tropics, it may be premised at the outset that this is less than would be required in colder climates, provided that the amount of external muscular work to be performed is the same in both instances. In consideriag the question of tropical dietaries, the fact that food gives rise to both heat and energy, when taken into the system, is too often overlooked. These, within certain limits, are complementary and vary inversely with each other — but the material from which both have their origin is fixed in quantity and has a definite chemical composition. A given amount of nutritive material has thus a positive potential value ; it will give rise to a variable amount of animal warmth and will permit the accomplishment of a variable quantity of external muscular work, but the sum of the two wiH never be greater than the caloric value of the quantity of food from which both were derived. Force and heat cannot be created from nothing. On the other hand, a portion of the food ingested may be excreted unused without passing into the system; or if it be digested and absorbed it may not at once be utilized, in which case the excess is stored up as fat within the organism, and becomes a reserve supply of heat-gen- erating and force-producing material which can subsequently be drawn upon as the needs of the system may require. It is evident that in the tropics, from the high external temperature, little food is required to main- tain the proper degree of animal warmth, and that the chief problem relates to the dissipation of such body-heat as may be produced beyond the needs of the system — as evidenced by the abnormally high bodily temperature noted in new arrivals in the tropics. Hence, if the external muscular work done in the tropics is the same as in colder climates, the difference THE HYGIENE OF HOT AND COLD CLIMATES. 865 in the quantities of food required in both, cases, over and above the amount necessary for the production of the energy needed in the performance of this fixed amount of work, will vary with the difference between the body- temperature and the temperature of the surroimding air. More food is obviously required for the maintenance of normal body-temperature when the surrounding air has a temperature of, say, 40° F. than when the latter is heated up to 85° F. It is true that, with the same diet, an excess of nutritive material not required for purposes of warmth or repair, if not stored up within the organism, might be used in the creation of energy, and thus would be available for the accomplishment of more work than would be possible in colder climates, where a larger proportion of the food must be devoted to the production of body-heat; but in practice this is not the case, no greater amount of work can be accomplished by the individual in the trop- ics — in fact, experience shows that even less is possible — and the storage or elimination of an unused excess of food, for the reasons previously detailed, is undesirable. These points can be illustrated by supposing a furnace having two steam boilers, one being used for the supply of steam necessary in heating a building during winter, while the steam in the other boiler furnishes motive power by which work is performed. By the combustion in a given time of a definite quantity of coal in this furnace, a definite quantity of energy is liberated which is variously manifested as heat used in warming the building or power for the performance of work, but the sum total of heat and work can equal only the energy latent in the fixed quan- tity of fuel consumed during the given period. If the weather so moderate as to allow great reduction or even the discontinuance of the operation of the steam-heating apparatus, it is evident that the fixed quantity of fuel is capable, through its combustion, of supplying additional energy manifest- ing itself as an increase in motive power by which more work can be per- formed. But if an increase in the work done cannot be accomplished by reason of the limits of strength of the operating machinery, if it cannot be run either at greater speed or for longer hours, it is obvious that this addi- tional supply of available energy caimot be utilized to advantage, and if the fuU amount of coal be actually consumed, the excess of steam produced must be discharged and let go to waste. The amount of food required by the human organism thus depends upon two factors, the work to be done and the animal heat to be created — and these cannot be properly considered except in relation with each other. Hence, imder exhausting labors and fatigues, with corresponding wear and tear of the muscular system, in the tropics as well as in cooler climates, a liberal supply of food is required in the production of energy and repair of systemic losses, and this is used by the soldier, imder such circumstances, with satisfaction and advantage. On the other hand, both theoretical con- siderations and practical experience go to show that soldiers need less food than is ordinarily required in temperate chmates, and at first are prone to eat too much, particularly of nitrogenous and fatty matter. Ultimately, however, after a sojourn of varying length in the tropics, want of appetite — nature's provision against excess — intervenes to diminish the dangers of over-eating. With respect to the quantity of food required in the tropics, it should 55 866 THEOEY AND PEACTICI} OF MILITAEY HYGIENE. be remembered that both the digestive and assimilative functions are im- paired under the influence of prolonged heat. Hence, work should not be imposed upon the alimentary tract in excess of its powers and the diet should be restricted as compared with that of temperate climates ; particu- larly since both diarrhoea and dysentery are known to be favored by the presence of a large amount of undigested food in the intestine, while tropi- cal anaemia may be hastened by mal-assimilation resulting from over- taxation of the digestive processes. The respiration, as has already been shown, is much less energetic after arrival in the tropics, and this, com- bined with the rarefaction of the atmosphere and other factors, results in a much less amount of oxygen being introduced into the organism than is the case in temperate climates. If this reduced quantity of oxygen finds in the organism an excess of alimentary substances, it is evident that the oxidation of the latter will be delayed even if ultimately complete, and the equilibrium of nutrition is thus impaired. It may fairly be assumed that the decrease in the quantity of carbon which the lungs can throw off in the tropics, amoimting, as has been shown, to probably about sixteen per cent., is an indication for the regulation of the diet as to kind and its corre- sponding reduction as to quantity. Further, according to Foster, the amount of heat evolved by the internal organs depends largely on their stimulation. In the case of the salivary glands, the temperature of the saliva during irri- tation of the chorda has been found to be 1° to 1.5° higher than that of the blood in the carotid artery at the same time ; and he states that, in aU probability, the investigation of other secreting glandular organs under excitement would yield similar results. Particularly is this true of the liver — an organ in which a large amount of heat is produced, as is shown by the fact that a temperature of 40.73° C. has been observed in the he- patic vein, while that of the right heart was 37.7° C. and that of the inferior vena cava 38.35° C. Hence, the excitation of the liver, through either the improper selection of foods or an excess of nutritive material requiring disposal, is to be avoided in hot climates. It is obvious that the consump- tion of an excess of food for the production of internal heat is here as un- necessary as it is imdesirable ; while the nutritive needs of the organism require a smaller amount of material to repair the systemic losses resulting from the usually less active life of the tropics. On the other hand, the conservation of the appetite to a reasonable extent, when seriously impaired by the effects of prolonged heat, is de- sirable in the diminution of anaemia and probably in the liability to mal- arial and other infectious diseases. To maintain a sufficient desire for food, the diet and its preparation should be frequently varied. The meager breakfast which suffices the native of the tropics, usually merely a cup of black coffee and a bit of bread, does not meet the wants of the United States soldier in hot countries. The morning repast should be light, how- ever, and by no means as substantial as is required in colder climates. Under no circumstances should the work of the day be begun until the appetite is moderately satisfied. Troops should be served with breakfast at about six o'clock, while dinner, the heavy meal of the day, should be taken about 11:30 o'clock. Supper should be light and should be served at about 5:30 in the afternoon. Food should not be eaten be- tween meals, nor should articles of food be brought into the barracks. The THE HYGIENE OF HOT AND COLD CLIMATES. 867 purchase by the men of food from native sources should be discouraged; this is particularly important during campaign, and during the last Ashanti expedition the British soldiers were not permitted to use food outside that officially provided. Nothing is more certain than that the character of the diet should vary with the climate ; a fact too frequently ignored by whites sojourning in the tropics. In selecting the food for such climates, care should natmally be taken to use but slightly those substances which go so largely to the production of animal heat; since the dissipation of the latter, for the rea- sons already enumerated, is but poorly accomplished. In character, the food should be plain and simple, readily digestible and nourishing without being too stimulating. While careful regulation of the food-supply is thus necessary, it is not expedient to imitate the natives of the tropics too closely in the special character of the articles of their diet, although it is none the less true that the food of the foreigner should possess such nutri- tive elements as, when taken together, would approach their dietary stan- dards. Habit, in the selection of articles of food, is to a certain degree hereditary, and the digestive machinery is not adapted to excessive or too sudden changes. Considerable modification of the ordinary dietary is cer- tainly necessary — not only in the interests of a lessened heat-production, but also so as not seriously to impair the digestive powers — but these changes do not necessarily require any modification in the character of the articles of the ration as at present supplied. The best diet for the tropics does not depend upon the use or disuse of any particular food-stuffs, as rice or bacon, but has relation merely to the proportion in which the proximate principles exist in the daily dietary, as expressed in terms of Calories and grams of fat, protein and carbohydrates. Kice is the chief article of diet among the inhabitants of the tropics, and is eaten in large quantities. The new-comer, however, cannot properly digest such a bulky diet; and even the natives are compelled to excite gastric secretion by the free use of peppers and other condiments, which, in large quantities, in the un- accustomed stomach of the foreigner, may tend to produce intestinal catarrh and indigestion. Vegetables should form a large part of the food provided for troops ; but care should be taken that they are always of good quality, and are fresh and properly cooked. Possessing a comparatively low nutritive value, the desired distention of the stomach should be given by foods of this class, and by their use constipation is largely prevented. In respect to their selection, reliance can safely be had upon the vegetable material at hand so abim- dantly provided by nature for human consumption. Eice is readily digested, but should be used by the foreigner only in connection with other foods ; and the same applies to yams, sweet potatoes and other tropical vegetables. The latter, being obtained fresh, may frequently be issued with advantage in place of vegetables transported from temperate climates, which deteriorate rapidly on arrival. Dry leguminous foods, as beans, peas and lentils, are highly nitrogenous, yet are less readily digested than meats. They should be used sparingly, and preferably in soups rather than any other form. They must be well cooked, as they are not otherwise acted on with advantage by the digestive juices. The use of raw vegetables, in salads, is not desirable for troops in the tropics, as favoring diarrhoea and dysentery ; and during 868 THEOEY AND PRACTICE OF MILITARY HYGIENE. the prevalence of diseases affecting the alimentary tract their use should be prohibited. A diet chiefly vegetable has been thought by some to favor the occurrence of tropical anaemia, but such objection is purely theoretical and not supported by facts. The Brahmins of India are strictly vegetarian in their diet, yet their freedom from disease, their physical powers and ex- pectation of life are said to be fuUy as great as those of the other native classes in contact with which they live. A vegetable diet in the tropics is soon craved by all, and if this be not supplied, soldiers wiU have recourse to native fruits, often to excess. Eipe fruit plucked directly from the tree is usually wholesome ; but when handled by dirty and possibly diseased natives, placed in filthy receptacles and stored temporarily in possibly infected places, it becomes a potent factor in the production of disease. This is especially the case with pineapples and such other fruits as are ordinarily peeled by the native vendors and exposed for sale in this condition to the sun, dust and flies. The danger in the use of fruit in the tropics is not so much due to its possession of any inherent deleterious qualities as it is to its frequent contamination with pathogenic bacteria before consumption. Oranges are particularly agreeable and bene- ficial and may be taken freely. Bananas should be used somewhat spar- ingly as being liable to produce indigestion and diarrhoea, and, like plan- tains, should preferably be taken cooked according to the native custom. Pineapples are not readily digested and should not be used in excess. Mangoes are much used by the natives as food. They are popularly sup- posed in India to give rise to boils, and in tropical America to produce yellow fever; apparently because these affections are most prevalent at a season when the mango is ripe, or shortly afterward. Cocoanuts, sapo- diUas, sugar-apples, mammey-apples, and other fruits may be used raw in moderation ; but where its nature permits, such fruit is stewed with ad- vantage. While fruit should habitually be used as a laxative in overcom- ing the constipating effect of climate, it should be remembered that its excessive consumption by the stranger is certain to be followed by intes- tinal disturbance. It is scarcely necessary to say that new arrivals wiU do well to be cautious in this respect, until they know what best agrees with them among those fruits with which they have no previous acquaint- ance. Those who have been accustomed in the temperate zone to much animal food, or, in other words, to a highly nitrogenous diet, have also generally been accustomed to a large amount of bodily exercise, and by this means have been able to maintain a healthy metabolic equilibrium. Unfortu- nately, however, the same amount of exercise wiU not ordinarily be secured with comfort or safety in verj' hot climates, especially by new-comers ; and thus the need for food of this character is gi-eatly diminished. Meats should thus be taken in moderation, and regulated in quantity accordiag to the repast. The use of flesh at aU three meals is undesirable ; and it should not be eaten, except as soup or flavoring, more than twice in the twenty- four hours. When used, it should be carefully prepared and well cooked, and should present its nutritive principles to the economy in a form readily assimilable and adapted to repair the losses of the organism, without leav- ing any excess of undigested refuse to irritate an overloaded and atonic ali- mentary tract. Soups, stews and rare roasts are hence to be preferred, and THE HYGIENE OF HOT AND COLD CLIMATES. 869 Ijoiled or fried meats should be avoided. ■ In hot countries, native meat, as a rule, is not tender in consequence of the necessity of cooking it withia a short time after slaughtering; and for this reason imported refrigerated meats are superior to the native article. In the tropics, beef is the standard animal food, but mutton is excellent if it can be procured. Pork is unde- sirable from its greasy, heavy and indigestible character. Native swine are largely feeders on filth and offal and their use as food should always be avoided. Chickens and eggs are excellent, but can scarcely be considered as normal constituents of the diet of the soldier. Fish, either fresh or salted, is of great value as not being a concentrated food and should be much used. Canned meats should never be employed where the fresh article is available ; and, when used, must be eaten within twelve hours after the can is opened. English authorities are united in their condemnation of aU highly spiced and peppery dishes iu the tropics, on the ground that they are largely responsible for the derangement of hepatic function so often seen, and that they produce congestion and irritation of the digestive organs. These conclusions would seem to be illogical. Chili, curry, soy and other carminatives, in considerable quantity, are apparently a necessity in secur- ing the proper digestion of the bulky foods used by the natives of hot coun- tries, and it is particularly noticeable that liver disease and disorders of digestion are infrequent in this native class. Hence the iU effects usually considered by foreigners as due to the high seasoning of the native cookery wOl probably be more justly attributed to their own almost universal use of a too rich, greasy and nitrogenous diet, unsuited to the climate. The Tropical Dietary. — ^While the army ration, in constituents and quantity, is established by regulations, the actual diet of the soldier, within certain limits, is what the company commander and his first sergeant and cook may choose to make it. It has already been stated that the tropical dietary is a matter of proximate nutrient principles and fuel value and not one of the use or avoidance of any special articles of food, and hence the present established ration contains within itself all the elements of a suit- able dietary for the tropics. There is, however, a best nutrient standard to which the food of the soldier serving in hot climates, particularly when per- forming the ordinary routine of garrison duty, should approximate in its chemical constituents and potentiality with regard to the production of heat and performance of work. What this approximate dietary standard should be, it is the purpose of this section to indicate. Various attempts have been made by physiologists and chemists to devise standards representing the amount of nutrients required, under vary- ing conditions, for daily sustenance. There are, however, two great diffi- culties in the way of setting up such standards. The first is that there is not sufficient definite knowledge on the subject of nutrition to permit of an exact statement as to how much the average man, doing a certain class of work, requires for the maintenance of his body in vigorous condition and for the creation of energy expended in the form of heat and work. The second difficulty depends upon the fact that different individuals of the same class, imder the same conditions, differ widely in their demands for food and the use they make of it. One wiU eat more and the other less, while both do the same amount of work ; or both will eat the same 870 TH^OEY AND PRACTICE OF MILITARY HYGIENE. food and do the same amount of work, yet one wiH be fat and the other lean.; or both have the same diet, yet one will be strong and capable of performing considerable work while the other will be weak and able to accomplish little. Exactly why individuals differ in their ways of utnizing their food, and how to measure these differences and make rules to fit them exactly, are problems which are as yet far from solution. The nutrition of man is by no means merely a question of grams of protein and units of energy, and hence the subject of dietetics can never be reduced to an exact science. The best that can be done is to make general estimates, with the understanding that such estimates are only approximately correct, even for a special class. These are reached by observing the amount and relative proportions of the food actually consumed by the individuals composing the class in question, and also by experiments in which the income and outgo of the body are directly compared. But little investigation has as yet been done by the latter method, and present knowledge of nutrition ipay be considered as based entirely upon observation and analysis of es- tablished dietaries, which have been shown by experience to possess suffi- cient reparative and potential value for the special conditions under which they are used. For present purposes, these dietaries should cover not only varying conditions of external muscular work but also of climate, so that comparison in the latter respect may be possible. For determining the diet of the soldier, it is necessary to refer to the dietaries of men at hard labor in various portions of the temperate zone and in the tropics ; the following table being intentionally made to include dietaries of this character for different countries in the northern portion of the temperate zone, since the United States army is heterogeneous in its composition, and the foreign-born element — ^largely drawn from the coun- tries named — undoubtedly brings with it into the military service the dietetic preferences resulting from previous habit : Typical Hard-Labor Bibtaries for the Northern Portion of the Tem- perate Zone. Si e" 1^ - go » England ■ — Royal engineers, active work. (Playfair.) Sweden — Mechanics. (Hultgren and Lander- gren.) Russia— Factory operatives, near Moscow. (Erismann) Germany — Machinists, Krupp gun works. (Prausnitz.) Southern Austria — Farm laborers, at harvest- ing. (OhlmilUer.) United States — Mechanics, Massachusetts and Connecticut. (Atwater.) United States navy ration. (Atwater.) United States army ration 144 189 133 139 159 154 143 164.2 Average 153 83 110 80 113 62 227 184 97.8 631 714 584 677 977 636 530 600 3,950 4,725 3,680 4,395 5,235 5,375 5,000 4,061 23.04 30.24 21.11 33.24 25.44 24.64 23.88 25.33 119.5 666 4,540 24.36 1:5.7 1:5.1 1:5.8 1:6.7 1:7 1:7.5 1:6.8 1:5 1:6.3 Total carbon 463.89 gm. ; nitrogen to carbon 1 : 19,4. THE HYGIENE OF HOT AND COLD CLIMATES. 871 As compared with the United States army ration, included in the above table, the average of these dietaries is seen to be slightly in excess in fats, carbohydrates and fuel value, but deficient in protein. On the whole, however, the difference is not great, and the sufficiency in amount and proper proportion of the food provided for the soldier serving in a more northern portion of this country is abundantly demonstrated. In the warmer portions of the temperate zone, but still well outside the tropics, the quantities of the several proximate principles required by the inhabitants are markedly inferior to the figures above given. The dietaries of these regions have not been as thoroughly studied as in countries lying in a cooler climate, but the following data are sufficiently comprehensive to be of both interest and practical importance : Typical Wobking Diets of the Southern Portion of the Temperate Zone. ils S s - ^ S ea Italy — Mechanics. (Manfredi.) Italy — Army ration, peace. (Molescliott) . . ■. Japan — Prisoners at work, Tokyo. (Eijk- man) United States Mexican, New Mexico, families. (Goss.) United States Negro — Southern Gulf States, families. (Atwater and Woods) Average 114 66 68 62 38 14 73 133 396 593 544 573 436 3,390 3,095 3,585 3,320 3,370 10,55 18.34 10.66 10.88 9.90 1: 6.3 1: 5.5 1: 8.5 1: 8.3 1:11.8 77 53:4 508 3,013 10.73 These figures, however, are based upon races, with the exception of the United States negro, of less body -weight than, those of colder climates, and hence are not properly comparable with similar figures for the latter class until reduced to a common standard in this respect ; since, according to Church, the capacity for muscular work may be considered as closely re- lated to body-weight. If it be assumed that laborers in the southern por- tion of the tempe-rate z^one have an average weight of 125 pounds, while the corresponding class in the cooler part of the same zone have an average weight of 145 pounds — about that given by statistics as the mean weight of recruits for the United States army— the above average figures should be corrected as follows : Protein, grams. Fats, grams. Carbohydrates, grams. Fuel value. Calories. Nitrogen, grams. Nutritive ratio (protein to energy). 89.3 61.94 589.28 3,493 14.3 1:8 Total carbon, 354.73 gm. ; nitrogen to carbon, 1 : 34.8 While the foods habitually used by natives of the tropics are well known to differ widely in character from those employed in temperate cli- mates, and while the existence of a certain deficiency in the native dietary in the matter of protein and fats has long been recognized, there has been but little investigation as to the force-value of the tropical dietary or to the exact qualities and relative proportions of the several proximate prin.- 872 THEOEY AND PRACTICE OF MILITARY HYGIENE. ciples entering into its composition. The question of tropical dietaries has, however, been locally studied by Maurel, in the island of Guadeloupe, by Church, in British India, by Eijkman, in Java, and by Lapicque, in Abys- sinia. The results obtained by these investigators in diverse portions of the tropical zone, although but few in number, nevertheless agree so closely in all respects that they may be accepted as conclusive and their average as fairly representing the nutrient standard of the laboring class of natives throughout the tropics. The average chemical composition of the four dietaries investigated by these observers is as follows : Protein, grams. Fata, grams. Carbohydrates, grams. Fuel value. Calories. Nitrogen, grams. Nutritive ratio (protein to energy.) ' 60.31 31.8 442.2 2,300 9.63 1:8.8 For purposes of comparison, however, these figures, like those for the in- habitants of the warmer portions of the temperate zone, must be reduced to the common standard of body-weight of 145 pounds — the average weight of laborers in the undersized races of the tropics being assumed to be about 115 pounds — and the above figures are thus proportionately increased, as shown in the following table : Protein, grams. Fats, grams. Carbohydrates, grams. Fuel value. Calories. Nitrogen, grams. Nutritive ratio (protein to energy). 76.18 40 560.01 3,900 12.18 1:8.8 Total carbon, 318.13 gm. ; nitrogen to carbon, 1:36.1. On contrasting the several dietaries which have been shown to obtain' with men having an average weight of 145 pounds, engaged at hard mus- cular labor, in the northern portion of the temperate zone, the southern portion of the temperate zone and in the tropics, the difference in the quantity and character of food taken is seen to be most marked, particularly in relation to the protein and fats. The difference in force- value between these dietaries is also very great, and even the use of carbohydrates, con- trary to usual ideas, is also diminished in the tropics. These typical diet- aries are shown in the following table : Climate. Korthern portion of temper ate zone Southern portion of temper ate zone Tropics 153 89.3 76.18 i i 119.5 61.9 40 l?i 666 589,2 560 4,540 8,493 3,900 24.86 14.3 12.18 ^ am 1:6.2 1:8 1:8.8 463.89 354.73 316.18 'SS . "Si So 1:19,4 1:24.8 1:26.1 It may, however, be urged that the marked variation in the composi- tion and force-value apparent in the above dietaries is due rather to racial preference than to climatic influence. This claim would scarcely appear to be well founded. It is a matter of common observation that natives of the tropics removed to colder climates soon adopt the dietetic customs THE HYGIENE OF HOT AND COLD CLIMATES. 873 of the region in which they may be resident. Further, it should be noted that Atwater and Woods showed the average daily consumption of food in twenty negro famiKes in the rural districts of southern Alabama to consist of 62 gm. of protein, 132 gm. of fats and 436 gm. of carbohydrates, and to possess a force-value of 3,012 Calories; while PrisseU and Bevier found that the average dietary of nineteen negro fa mili es of the same class, resi- dent in northern Virginia, yielded 109 gm. of protein, 159 gm. of fats and 444 gm. of carbohydrates — ^with a force-value of 3,745 Calories. It is idle to assume that this great difference in the composition and nutrient value of the dietaries for corresponding classes of the same race, resident in different latitudes, can be dependent upon other than climatic conditions. Hence it may be assumed that the food of human beings, both in relative proportion and nutrient quality, varies directly with temperature, as approximately expressed by latitude. The standard dietaries having been established for laboring men per- forming hard work under diverse climatic conditions, it becomes necessary to examine the present United States army ration with a view of ascertain- ing the nutritive value of its several components, and determining whether the quantities in which their issue is authorized will permit their combina- tion in a daily allowance, not only desirable in theory and well qualified to maintain the health and vigor of the soldier but also thoroughly prac- ticable under all conditions of military service. On referring to the four combinations of the articles of the ration given on pages 162 and 163, it is seen that the first combination, as compared with the average dietary for individuals of the same weight native to the tropics, presents a great excess in protein, fats and fuel value — even the carbohydrates being largely increased. In the second arrangement, the fats are present in five times the quantity apparently sufficient and desirable under tropical standards, the protein is in considerable excess and the fuel- value unnecessarily high, while the deficiency in carbohydrates is notice- able. In the third dietary, the fats and protein are both in excess, but the quantity of carbohydrates is markedly deficient. The force-value of this combination is probably not far from the actual requirements of the system, in the tropics, as regards energy. In the last, arrangement of the articles of the ration, the protein is seen to be present in slight excess, while the fats and carbohydrates are markedly deficient, the former especially so. The force-value of this dietary, also, is insufficient to meet the needs of even moderate muscular labor. The conclusion is therefore justifiable that while the several articles composing the ration are well selected, the maxi- mum quantities in which their issue is now authorized are so proportioned that their combination in a dietary, approximately similar to the nutrient standard of native laborers in the tropics — even under conditions of equality as regards weight — is practically impossible. It is therefore desirable that the company commander should use only such quantities of these ration components as would permit of proper dietary requirements for tropical ser- vice, as based upon the amounts of protein, fats and carbohydrates desira- ble for the daUy dietary. "With respect to the quantity of proteid required, the proteid molecule, as shown by Krukenberg, Pavy, Schiitzenberger and others, is not to be re- garded as a perfect chemical body, but as a complex, composite mixture 874 THEORY AND PEACTICE OP MILITARY HYGIENE. of a glucosidal nature, containing nitrogenous, carbohydratic and fatty radicles. Protein has been experimentally decomposed into these radicles, outside the body, by the above investigators ; and it has been determined by Cohnheim, Seegen, Kiilz, Mering and others, through artificial condi- tions of diet, that the same cleavage occiirs as a result of the processes of oxidation within the organism. The non-nitrogenous radicles have as their object the production of energy ; and when the systemic needs are satisfied as regards nitrogen, it is obvious that, for the tropics, such force-food as may still be required is preferably supplied in the simple proximate forms not requiring such cleavage — ^with its necessary production of heat — and not yielding, in the process of decomposition, considerable quantities of a substance which is in excess of the immediate requirements of the organ- ism, and, as stated by Foster, can be stored up in but extremely small part in the system, and hence merely requires elimination as an excrementitious body. Particularly is this the case where the need for internal heat is ob- viously lessened, and where the renal function, from the causes already mentioned, operates at a disadvantage. It is hence extremely important that protein be supplied in the tropics purely for the purpose of systemic repair and not be relied upon for the creation of any considerable proportion of the energy required by the organism. The ingestion of a certain amount of nitrogen is indisputably necessary to health, and with its deficiency the food ceases to be digested and a condition of inanition ensues. This, how- ever, is no argument for its supply in excessive amount; and the nitro- genous intake — for the most satisfactory accomplishment of the metabolic processes — should be directly proportioned to body-waste. According tO' Gayet, the average man at ordinary labor, in the temperate zone, loses 20 gm. of nitrogen daily, nearly all of which is in the urine. Eijkman, in Java, found that the average excretion of nitrogen in Malays of a similar class was 7.817 gm. ; which, being reduced to a common standard of weight at 145 pounds — the Malays averaging 111 pounds — gives 10.21 gm., or about one-half the quantity ordinarily eliminated in temperate regions. The nitrogen in the standard diets for laboring men in cool climates, pro- posed by Playfair, Moleschott, Atwater and others, varies from 18.35 to 20.29 gm. Notter and Firth give 11.6 gm. as the daily allowance for a mere subsistence diet in temperate regions, and state that even as much as 32 gm. may be required during great exertion. On referring to the table already given showing the dietaries employed by laboring classes in the tropics, reduced to a common standard of weight for purposes of comparison, it is seen that the hard-working native of the low latitudes ingests an aver- age of 12.83 gm. of nitrogen, or an amount only slightly in excess of the theoretical requirements for bare subsistence for men of the same weight in temperate climates. This deficiency in the amount of nitrogen ingested by the native is, however, apparent rather than real; for the above quantity, small though it may seem, has been shown by experience through untold generations to be not only sufficient for the maintenance of life and health in the tropics, but also ample for the greater demands upon the organism re- sulting from labor. Maurel, in his study of the natives of Guadeloupe and Guiana, found that their diet was almost wholly vegetable. From estimates based on official figures, he showed that the inhabitants of Guadeloupe used a daily average of only 20 gm. of meat per capita, and that only one-seventh THE HYGIENE OF HOT AND COLD CLIMATES. 875 of the vegetable food was imported in the form of the cereals of the tem- perate zone ; the remaining six-sevenths being made up of yams, cassava, sweet potatoes, bananas, mangoes and other fruits. Similar customs as regards food are said by Eijkman to prevail among the Javanese Malays ; and in India and Abyssinia, Church and Lapicque found that the natives rarely used animal material in any form. For natives of the tropics, it may therefore be accepted that the vegetable kingdom is almost wholly the source from which their food is drawn, and that but little of the vegetable material so used is imported in the form of cereals grown in cool climates. These facts are extremely important, for fruits and vegetables grown in the tropics, at least as far as the western hemisphere is concerned, are much less rich in nitrogenous constituents than are the vegetable foods indigenous to the temperate zone. A comparison of the vegetable materials most com- monly employed as staple foods in the tropics and in cool climates shows the following differences : Vegetable Foods CniEFiiT Used en the Tkopics., 11 is p.« ft |s S3 . Cassava 61.30 69 71.86 75.41 75.3 13.3 0.64 1.8 1 1.49 1.3 8 0.103 .388 .160 .330 .308 1.380 .17 .70 .30 .'e' .3 36.50 36.10 35.05 15.36 31 78.8 0.88 1.30 1.03 7.04 1 .3 0.51 Sweet potato (edible portion) Yam 1.10 .86 Sugar-cane .69 Ripe bananas (edible portion) Rice .8 .4 Average amount of nitrogen, per cent., .378. Vegetable Foods Chlbfly Used in Tempbkatb Climates. li 'I 11 Is Zip. III So o a*5 White potato (edible portion) Wheat flour Oatmeal 78.3 13.8 7.3 13.5 11.9 13.7 3.3 10.8 16.1 9.3 10.5 7.1 0.353 1.553 3.575 1.473 1.530 1.135 0.1 1.1 7.3 1.9 3.3 .9 18.0 74.6 66.6 UA 66.3 78.5 0.4 .3 .9 1 6.5 1.0 .5 1.9 Oornnripal eranular 1 3.6 Rye .8 Average amount of nitrogen, per cent., 1.434. In these two groups of food-stuffs, the great inferiority of the vegetable diet of the native in the tropics, as regards available nitrogen, is at once apparent ; the vegetable and cereals most commonly used as food in the temperate zone containing, in a given weight, almost exactly four times more nitrogenous material. Hence, it is evident that the native diet in the tropics is doubly inferior as regards nitrogen ; meat being but little used, while the vegetable foods which replace the cereals of temperate climates contain but a small proportion of this element. The fact may here be emphasized that nature has laid down certain laws as regards alimentation which it is the highest wisdom not to disre- 876 THEORY AND PRACTICE OF MILITARY HYGIENE. gard. It is not a matter of theory but an unrecognized chemical instinct which leads the native of the tropics to make his choice of diet and nature's provision of aliment accord so closely. The inhabitants of warm climates, civilized and savage, succeeded in properly adjusting their diet through experience alone long before any theories as to the proper diet for such climates were advanced ; and it is worthy of note that not only is a light vegetable diet, containing proportionately little nitrogen, sufficient to main- tain health and strength ia the native of the tropics, but whites even, who may have been born iu hot countries, intuitively adopt a similar regimen and thrive upon it. Habit, in the use of pertain classes of food-stuffs, certainly operates agaiast a change of diet ; yet Eijkman found, in Java, that the food of resident whites — born in Europe — ^ultimately approached the native dietary, presenting a niarked decrease in both protein and fats. Analyses of this modified European diet gave an average content of 99.6 gm. of protein, 83.8 gm. of fats and 284.2 gm"! of carbohydrates. The fact that an excess of meat iu any form, greasy meat especially, soon be- comes distasteful under the ordinary conditions of life in the tropics is certainly a powerful argument for an alteration iu diet ia favor of a dimi- nution of protein as well as fats. The most striking effect of a highly nitrogenous diet is the increase in the nitrogenous metabolism of the body, and to a lesser degree of the non- nitrogenous also. This increased metabolism, through the amount of heat necessarily generated in the process, is clearly imdesirable in warm cli- mates. Further, the deficient supply of oxygen available in the tropics impairs the combustion of proteids, and under such conditions the over- loaded system habitually contains an undue amount of unoxidized nitrog- enous matter, which in an oxidized state would be eliminated by the kidneys. Albuminates, and nitrogenous compounds generally, undergo change and are excreted principally as urea ; therefore an excess of albuminous food throws more work on the kidneys, which may induce disease. Nitrogenous matter being in excess and the secretion of the urine by the kidneys being decreased, there may be deposits in the urinary passages in the shape of uric acid, or in other parts as urates, through the kck of sufficient fluid for their solution. As to the liver, Eochard, Moore, Nielly, Eattray, Jousset, Maiu-el, TreUle and others have observed the directly injurious influence of a too nitrogenous and greasy diet in the production of disorders of this organ. Hepatic disease, while extremely common among the whites of India and other tropical regions, is rare among the native population. The idea has been advanced that the native enjoys an immunity to this affection as a result of acclimation rather than diet; but this theory is contradicted by Maurel, who states that he, with others, has repeatedly seen congestion of the liver occurring in natives of the tropics, who a few months before, by reason of circumstances, had adopted the much more nitrogenous diet of the temperate zone. This view is upheld editorially in a recent issue of the Journal of Tropical Medicine, which calls attention to the greatly in- creased liability to disease of the Uver among Asiatics who have become semi-Europeanized, and connects it with the fact that these individuals crave and use the same bulk of the more concentrated and nitrogenous diet of the European as they do of their own native foods. Further, to show THE HYGIENE OF HOT AND COLD CLIMATES. 877 the injurious effect of a nitrogenous diet ia hot countries, laboratory experi- ments are not wanting. Maurel, in Guiana, fed a series of rabbits upon a vegetable diet, while another group was fed entirely on cheese. The investi- gation extended over a period of ten months and the results were conclusive, showing a less increase iu the weight of the first group than occurred in the cheese-fed rabbits. Not only was the total weight of the second series of animals much greater than that of the first, but the disparity in hepatic enlargement was even more marked, the livers of the latter class showing disproportionate increase in size and also exhibiting manifest changes — being hard, mottled and presenting a condition of hypertrophic cirrhosis. In a second series of experiments, the results, though positive, were slightly less marked, since the experimental feeding continued for only six instead of ten months, and the influence of a nitrogenous diet was not so pronounced upon the liver. The following results were obtained by him : DUKATION OF EXPEEIMENT, TbK MONTHS, June, 1881, to Ap RiL, 1882. TOTAL Weight. At End of Experiment. Before experiment, grams. After experiment, grams. Weight of liver, grams. Relation of weight of Uver to total weight. Eabbit Xo. I. (vegetable diet) Rabbit Xo. II. (cheese diet) 650 580 1,210 1,780 37 86 1:32.70 1:20.69 Second Expekiment, Ddbation Six Months, April, 1882, to October, 1882. Rabbit No. I. (vegetable diet) Rabbit No. II. (vegetable diet) Rabbit No. III. (cheese diet). . . Rabbit No. IV. (cheese diet) . . . Total Weight. Before experiment, grams. 629 645 467 565 After experiment, grams. 1,160 1,880 1,365 1,370 At Esb of Experiment. Weight of liver, grams. 33 44 48 45 Relation of weight of liver to total weight. 1:35.15 1:43.72 1:28.44 1 : 30.44 For the three rabbits given a vegetable diet, the ratio of the weight of the liver to the total body-weight was 1:36.85 at the time of death, while the ratio for the cheese-fed rabbits in this respect was 1 : 26.52. In view of the clinical experience and experimental results, as noted above, no further argvmient as to the influence of a too nitrogenous diet in the tropics in provoking liver disease is required. From what has been said, it may be accepted that the full nitrogenous content of the established ration is in excess of the needs of troops per- forming garrison duty in the tropics, and under such circumstances the use of food-stuffs containing a considerable proportion of nitrogen may be safely and advantageously diminished. This is perhaps best accomplished at the expense of the meat component, which, besides protein, also contains a considerable proportion of fats. A complete fall to the nitrogenous level of the native of the tropics is undesirable, however, and it is probable that the daily allowance of nitrogen cannot be safely reduced below 16 gm. — represented by 100 gm. of protein — even though this amount is in con- 878 THEORY AND PRACTICE OE MILITARY HYGIENE. siderable proportionate excess of the nitrogenous iatake of the correspond- ing native class of the tropics. In hot climates, where the human organism instinctively feels the need of a loss of heat rather than its creation, the consumption of fat — a heating food of the highest degree — should be reduced to the minimum, and largely replaced by that of sugars and starches, except ia the case of troops perform- ing hard service, where force-food of high potential value is rec[uired. The craving for sweets noted among our troops stationed in the PhUippiues gives practical evidence on this point. Kubner calculated that 100 parts of fat, burned within the body, yield as much heat as 232 parts of starch or cane-sugar; and the distaste for fats in any considerable quantity, so early acquired in the tropics and so noticeable during the summer weather of tem- perate oLiniates, may be regarded as evidence of an unconscious but in- stinctive recognition of the fact that a dietary of decreased caloric value is sufficient for the needs of the organism exposed to high temperatures and performing no severe muscular work ; the more concentrated heat-producers being rejected in favor of bulky vegetable foods of lower potential value. This dislike of fat under conditions of high temperature and but moderate exercise is too fuUy appreciated to require the production of evidence on this point. It is of interest, however, to recall the aversion with which the ration of bacon was regarded by troops in Cuba and Porto Eico during the war with Spain ; while CardweU reported from Manila that " the salt meat (bacon) was in great part wasted and need not have been issued except in sufficient quantity to provide cooking fat." During hard field service, how- ever, fats may be relished in the tropics, since they supply in concentrated form the energy required for the performance of exhausting labor. As compared with carbohydrates, fats, as a whole, are notably less di- gestible, and thus increase the evolution of heat through the more active chemical processes in the intestines. Furthermore, they are burned with more difficulty within the organism, since there is sufficient oxygen in the carbohydrate itself to form water with the hydrogen present, while fats require additional oxygen to combine with their hydrogen for their com- bustion and elimination. Hence, in herbivora, according to Foster, a larger proportion of the oxygen consumed reappears in the form of carbonic acid than is the case with carnivora, subsisting chiefly on proteid and fat. That this difference is by no means small is shown by the fact that the so-called respiratory quotient, obtained by dividing the excretion of carbonic acid by the consumption of oxygen, by volumes, is about .9 in herbivora and about .7 in carnivora; a difference of 22 per cent. In the tropics, how- ever, it has already been shown that there is a greatly diminished value, as regards oxygenation, to the respiratory act; and under such circum- stances the amount of oxygen, already small, available for the needs of the organism as regards the elimination of carbon, would be seriously en- croached upon in the oxidation of a diet largely composed of fatty material. Furthermore, an excess of hydrocarbons in the food calls for increased he- patic action in the production of bile, since it has been abundantly demon- strated that the latter is a prominent factor in the digestion of fats, as shown by the fatty stools which follow obstruction or ligature of the bile-ducts. That this hyper-stimulation of the liver — with its many evil results, elsewhere discussed — actually does occur in the tropics where more fats THE HYGIENE OF HOT AND COLD CLIMATES. 879 are introduced into the system than can be readily utilized, is shown by the bilious diathesis so common among gross eaters in warm climates, as characterized by excessive bile production and later by hepatic congestion. Fats and carbohydrates are much more akin to each other than is either to proteid ; and if, as stated by Poster, fat may be converted into sugar either when about to be incorporated into the organism or when being decomposed into its ultimate products, it might reasonably be expected that carbohydrates and proteid, with little or no fat, would form a satisfac- tory diet. That this conclusion is, in practice, largely borne out by facts is shown by reference to the foregoing tables in connection with the com- position of vegetable food-stuffs, in which the fatty constituent of the vegetables ordinarily composing the diet of the native of the West Indies is only .32 per cent, while the corresponding part of the diet in tem- perate climates contains 2.23 per cent., or an amount seven-fold greater. On this point, however, experience is probably to be trusted. Natives of hot countries, when they can afford it, generally use a small amount of fats as such — as the clarified butter of India, the salt pork of tropical America, the olive oil of the Mediterranean districts and the palm oil of equatorial Africa — but where such a great deficiency exists in the natural fats of the vegetable portion of the diet, even the use of an apparently considerable amount of bacon or other greasy food would fail to make good the deficiency in fats as compared with the dietaries of temperate regions, depending upon the above cause. It is probable, also, that a certain quantity of fatty material, together with the proteid and carbohydrates, assures a better use of the alimentary principles and reduces to a minimum the quantity of each which should be ingested. While it may, then, be conceded that a certain quantity of fatty food is a desirable component of the diet in warm climates, it is certainly true that the amount so taken should be relatively small, and that the proportion commonly maintained in temperate climates is far in excess of the needs of the organism in the tropics. This fact is abundantly demonstrated by referring to the average dietary for men at hard work in the north temperate region and that for the corresponding class in the tropics, as previously given; the fats and carbohydrates being seen to exist in the ratio of 1 : 5.5 in the cold climates, while in the tropical dietary the relative proportion is 1 : 14 for men of the same weight. With such wide variation in the relation of these proximate principles, and in view of the fact that a considerable diminution in protein has also been shown to be desirable, it is evident that a sudden reduction of fat in the ration to the low standard of the native dietary in the tropics might readily provoke such alteration of metabolic function and such in- terference with existing processes of digestion as would result in serious dis- comfort and positive detriment to the individual. The dietetic customs of a lifetime cannot be entirely changed in a day, and a stomach accustomed to rich and concentrated food would undoubtedly find difficulty in at once properly digesting a far more bulky and less nutritious diet composed chiefly of vegetable material. For the new-comer in the tropics, habit as weU as climate must be given consideration in the selection of diet ; and it is therefore probable that no smaller proportion than that of one part of fats to ten of carbohydrates would be to the best interests of the United States soldier under the routine duties of garrison Hfe. 880 THEORY AND PRACTICE OF MILITARY HYGIENE. Carbohydrates are justly regarded as the chief source of carbon supplied to the organism in the production of energy. This, however, is due rather to the much greater quantity of carbohydrates ingested, as compared with the fat and protein constituents of the ordinary diet, than to a high propor- tion of this element in the carbohydrate itself, for the amount of carbon in starch and sugar is relatively low. Notter and Firth state that carbohy- drate contains only 44 per cent, of carbon, where fat contains 76.5 per cent, and even protein contains 53 per cent. Through the considerable quantity of protein which enters into the diet, it is thus evident that the latter plays no small part in determining the carbon intake, as utilized for the creation of energy. The urea of the urine practically represents the whole of the nitro- gen which passes from the body, and in any given quantity of urea the amount of carbon is far less than that found in the quantity of protein containing the same amount of nitrogen. Foster states that the percentage composition of the two is as follows : Carbon. Hydrogen. Oxygen. Nitrogen. Sulphur. 35 53 6.66 7.30 26.67 33.04 46.67 15.53 Protein 1.13 It is thus readily seen that 100 gm. of protein, which have been sug- gested as furnishing about the amount of nitrogen desirable for the ordi- nary allowance of the United States soldier in the tropics, contains as much nitrogen as 33.3 gm. of urea; but the 100 gm. of protein contain 46.4 gm. more carbon than do the 100 gm. of urea (53 : 6.66, or about the proportion of 8 : 1). Hence the daily allowance of protein for tropical service, in pass- ing through the body and giving rise to urea, would leave behind 46.4 gm. of carbon to combine with oxygen and undergo elimination as carbon di- oxide. It has been shown that the average diet of laboring men at hard muscular work in the cooler portion of the temperate zone contains 152 gm. of protein, and reduction in this respect to 100 gm., the proposed standard for the tropics, implies a loss of 15.08 gm. of carbon previously available for purposes of energy. It is true that a certain amoimt of pro- tein taken in as food, as shown by Mallet, is not directly decomposed to the comparatively simple forms of urea and carbon dioxide, but, retaining a greater proportion of carbon, is excreted as creatinin or uric acid — bodies which, intermediate between protein and urea, form a series in which the proportion of nitrogen becomes larger and the carbon smaller — and it is probable that the amount of these substances is considerably increased in the tropics through deficiency of oxygen available for the metabolic proc- esses of the organism. In quantity, however, they are undoubtedly at aU times so small as to be safely disregarded for the purposes of the present calculation. As regards fats, as stated above, carbon enters into their composition to the amount of 76.5 per cent., and it has been shown that for the tropics the proportion in the dietary of one part of fats to ten of carbohydrates probably redounds to the best interests of the American soldier. On re- ferring to the table giving the proximate composition of the average diets of hard-working men in the cooler portion of the temperate zone, it is seen that the amount of fats ingested by this class, 119.5 gm., would be re- THE HYGIENE OF HOT AND COLD CLIMATES. 881 duced, according to the above proportion, to 66.6 gm., or, ia round num- bers, to a daily allowaiice of about 65 gm. in hot climates. This amounts to a reduction of 54.5 gm. of fats and 41.69 gm. of carbon; making the total loss in carbon, due to diminution ia the fat and protein constituents, amoimt to 56.77 gm. daily. The average working diet for cool climates, just referred to, contains 453.39 gm. of carbon available for the mainte- nance of body-heat and the performance of external muscular work ; this quantity, on subtracting the 56.77 gm. of this element withdrawn from the same diet through proposed reduction in fat and protein, being reduced to 397.62 gm. But it has been shown that the native of the tropics performs hard labor on a diet which, even when proportioned for an average weight of 145 pounds, yields only 319.16 gm. of "carbon presumably available for purposes of energy. It is undoubtedly -true that this relatively small amount of carbon, required by the natives of the tropics, expresses to a con- siderable degree the lessened amount of energy necessary in the maintenance of body -heat in hot climates, and hence approximation to the carbonaceous level of the native dietary would seem to be desirable. On this point, how- ever, the question of previous habit must be given consideration, as is also the case with respect to the fatty constituents of the diet, and such great reduction in the carbohydratic element in the food would, in reducing the nutritive value of the diet, unduly decrease its bulk. Further, the work required of the soldier, even under conditions of garrison life, may at times be somewhat greater than that performed by the native laborer in the tropics. It has been stated that a greater part of the carbon oxidized within the organism is derived from carbohydrates, the latter being regarded purely as a force-food and as the chief source of energy within the body. Such material is capable of largely replacing fat in the dietary, diminishes nitrogenous metabolism, yields no end-products to be excreted by the kidneys, is readily assimilated and, when in excess, is largely stored up with^ the organism as glycogen and adipose tissue. The ingestion of car- bohydrates, therefore, in quantities greater than are required for the imme- diate needs of the economy, while not without certain untoward effects upon the system, is undoubtedly far less inimical to health in the tropics than where there is an excess of protein or fat in the dietary. It is probable, therefore, that further reduction in carbon for the proposed tropical stand- ard of diet need not be great, as far as any seriously unfavorable effect upon the organism is concerned, and it has been advanced by the writer, in his Prize Essay to the MUitary Service Institution, on the ideal ration for an army in the tropics, that about 380 gm. of carbon available for purposes of energy should be supplied daily, not including the carbon required in the formation of urea — this being yielded by the proximate principles of the subjacent dietary. From what has been advanced, it is seen that the proportionate com- position and fuel value of the proposed tentative dietary standard for United States troops, performing routine duty in the tropics, is as follows : Protein, grams. Fats, Rrams. Carbohydrate, grams. Fuel value. Calories. Nitrogen, grams. Total carbon, grams. Nutritive ratio protein to energy). 100 65 650 3,481 16 390 1:8 56 882 THEORY AND PRACTICE OF MILITARY HYGIENE. That this nutritive standard is sufficient for such conditions, in each and all respects, is shown by the fact that it closely resembles the dietary found by Atwater to be employed by farmers in the northern part of New York State. Certaialy an allowance of food adequate for the performance of hard labor in a more rigorous climate should abundantly suffice under the condi- tions of temperature and external muscular work for which the above stand- ard is proposed. The proximate alimentary principles, whose quantities and relative pro- portions are given in the above nutrient standard for the tropics, can be properly apportioned in the dietary for hot climates only as a result of an accurate knowledge of the percentage composition of such articles of food as may be selected to enter into its composition. The deter- mination of these food- stuffs, for the soldier, is an easy task. The present United States army ration is made up of admirably se- lected articles in more than sufficient variety for this purpose; and it is therefore not only wholly unneces- sary but quite inadvisable to consider, in this connec- tion, any nutritive substan- ces outside those articles legally established as com- ponents of the food for the soldier. The proximate composition of these has long since been determined — as given on pages 161 and 162 — and hence the matter resolves itself into the simple problem of so proportioning the quantities of the nutrient articles al- ready provided that, when brought together in varying combination, the resulting dietary will in each case approach the theoretical standards to a reasonable degree. It is not, however, intended that the daily intake of the several proximate principles shall exactly correspond with the quantities laid down therein, for this is manifestly impracticable for the military ser- vice, and even if its accomplishment were secured it is more than doubt- ful if there would be any resulting advantage. The economy readily adapts itself, in the matter of food, to present necessity, and slight defi- ciency in any nutritive principle is readily made good, particularly in the matter of fats and carbohydrates, from the reserve of these materials stored up within the organism — small systemic losses being subsequently Fig. 371.— 1. Standard dietary as Kiven by typical dietaries of men at hard labor in the northern portion of the temperate zone. 3. Proposed dietary lor garrison duty in the tropics. 3. standard dietary lor native laborers in the tropics ; based on the weight ol 145 pounds for purposes of comparison. 4. Standard dietary ol the laboring class of natives in (he tropics (Java, British India, Guadeloupe, Abyssinia), as determined from the food actually consumed by them at normal body weights. THE HYGIENE OF HOT AND COLD CLIMATES. 883 compensated for by corresponding excess. It is true, also, that the needs of the economy, as shown by appetite, are subject to wide variation ; and hence it may be accepted that slight but carefully considered alterations in the constituents of the daily dietary, far from being detrimental, are productive of actual benefit. It is obvious, also, that the amount of work to be performed wiU not be the same under all circumstances, and hence the question should be considered of utilizing the components of the ration in such quantities as to furnish dietaries properly varying in poten- tial and nitrogenous value. It is believed that this is accomplished in the f ollowiug modifications of the dietaries already shown to be most commonly used by the United States soldier in temperate climates; the subjoiued table showing the nutrient value of a proposed dietary for the tropics, containing the greatest amount of food material to be used by the soldier except when on field service : DlBTAKT I. Artloles. Quantity, ounces. Protein, grams. Fats, grams. Carbo- hydrates, grams. Fuel value. Calories. Nitrogen, grams. Fresh beef 10.0 18 2.4 16 3 8.5 41.68 55.08 15.16 9.50 1.77 44.75 5.60 1.22 .45 1.58 38b'. 46 40.18 81.70 33.80 94.25 590 1,850 240 380 220 397 6 67 Flour 7.90 Beans 2 42 Potatoes Dried fruit 1.52 .37 Suffar Total 52.9 123.19 53.55 630.39 3,677 18.78 Total carbon, 395.14 gm. ; nitrogen to carbon, 1 : 19.6. The following table shows a proposed dietary in which the fatty con- stituents attain their maximiim and the potential energy is high : DiBTART II. Articles. Quantity, ounces. Protein, grams. Fats, grams. Carbo- hydrates, grams. Fuel value. Calories. Nitrogen, grams. 6.0 18 2.4 2 3.5 15.64 73.12 15.16 1.77 105.06 6.63 1.22 1.58 37l'.8i 40.18 50.70 94.25 1,042 1,926 340 220 397 3.49 Hard bread 11 74 Beans ... 2 42 .27 Sugar Total 31.9 105.69 114.44 556.94 3,825 16 93 Total carbon, 328.76 gm. ; nitrogen to carbon, 1: 23. The nutrient value of the ordinary dietary is as follows : Dietary III. Articles. Quantity, ounces. Protein, grams. Fats, grams. Carbo- hydrates, grams. Fuel value. Calories. Nitrogen, grams. Fresh beef Soft bread Potatoes and onions. Dried fruit Sugar Total. 10.0 20 16 8 3.'5 41.68 53.83 8.60 1.77 44.75 6.80 .72 1.58 399.30 73.09 50.70 94.25 590 1,506 340 320 397 52.5 105.88 53.80 517.34 | 8,053 6.67 8.61 1.40 .27 16.95 Total carbon, 828.76 gm. ; nitrogen to carbon, 1 : 18. 884 THEOEY AJSTD PEACTICE OF MILITARY HYGIENE. For the following combination, the several articles of the ration most closely approaching in character to the food materials used by natives of the tropics — proportioned in quantity according to the standard proposed for hot climatesr — ^have been selected: DlBTART IV. Articles. Quantity, ounces. Protein, grams. Fats, grams. Carbo- hyarates, grams. Fuel value. Calories. Nitrogen, grams. Fresh fish (cod) whole 14.0 20 4 16 3 3.5 31.73 53.83 8.75 8.17 1.77 0.79 6.80 .45 .54 1.53 299.20 88.87 65.80. 50.70 94.25 120 1,506 407 297 220 341 5.07 Soft bread 8.61 Itice 1.40 1.36 Dried fruit .27 Total 64.5 104.25 10.11 598.82 2,947 16.71 Total carbon, 327.50 gm. ; nitrogen to carbon, 1 : 19.6. On averaging these four dietaries, the mean nutrient composition is seen to be as follows : Dietary. Quantity In ounces. Protein, grams. Fats, grams. Carbo- hydrates, grams. Fuel value. Calories. Nitrogen, grams. Ko I 52.9 31.9 52.5 64.5 50.4 123.19 105.69 105.88 104.25 109.06 53.55 114.44 53.80 10.11 87.97 630.39 556.94 517.24 598.82 560.85 3,677 8.825. 3,033 2,947 3,375 18.78 No 11 16.92 No. Ill 16.95 No IV 16.71 Average 17.34 Total carbon, 350 gm. ; nitrogen to carbon, 1 : 20. It will be observed that while the above dietaries differ considerably among themselves, yet when averaged together in equal proportions they do not greatly vary from the nutritive standard for the tropics already proposed ■ — and this is an additional reason why a selection of the same articles of the ration should not be made from day to day. It is seen that the above average dietary, as compared with the proposed nutrient standard, is still slightly deficient in fats and fuel value and a trifle in excess as regards protein. These defects, if they may be considered such, are, however, readily corrected by a rotation of dietaries, in which Dietary II. is used twice where Dietaries I., III. and IV. are each employed but once. The results of this change are as follows : Dietary. Quantity in ounces. Protein, grams. Fats, grams. Carbo- hydrates, grams. Fuel vaJue, Calories. 52.9 123.19 53.55 630.39 3,677 31.9 105.69 114.44 556.94 3,825 31.9 105.69 114.44 556.94 3,825 52.5 105.88 53.80 517.24 3,053 64.5 104.25 10.11 598.92 2,947 46.7 108.38 69.43 572.06 3,465 Nitrogen, grams. No. I.... No. II. . . No. II. , . No. III. . No. IV. . Average. 18.78 16.92 16.92 16.95 16.71 17.26 Total carbon, 363.33 gm. ; nitrogen to carbon, 1 : 21. THE HYGIENE OF HOT AND COLD CLIMATES. 885 Tor the production of a daily dietary closely approximating the nutrient standard already proposed, the use of the articles of the ration in the fol- lowing quantities is suggested : ass ■gss ^■o bo Fresh beef (quarters) Or fresh mutton " pork " bacon " salt beef " dried fish (cod) " fresh flsh, average (whole) . Flour , Or soft bread " hard bread , " cornmeal , Beans , Or peas • " rice " hominy Potatoes Or potatoes 80 per cent., and onions 30 per cent " potatoes 70 percent., and canned tomatoes 30 per cent Dried fruit (average) Sugar , Or molasses , " cane syrup 10.0 10 6 6 10 10 14 18 30 18 30 3.4 3.4 4 4 16 16 16 3 3.5 Igill 1 gill, 41.68 46.30 37.54 15.64 40.37 45.37 31.73 55.08 53.83 73.13 50.40 15.16 16.38 8.75 9.30 9.50 8.60 8.16 1.77 44.75 63.90 112.54 105.06 64.68 1.13 .79 5.60 6.80 6.68 13.40 1.33 .75 .45 .67 .45 .73 .58 1.58 380.46 399.30 371.81 435.80 40.18 41. 88.67 88.75 81.70 73.09 62.59 33.80 94.25 56.05 56.25 590 720 1,093 1,042 688 197 120 1,850 1,506 1,936 1,986 240 346 407 430 380 340 297 220 397 269 269 6.67 7.35 4.40 3.49 6.44 7.26 5,07 7.90 8.61 11.74 7.99 2.42 3.62 1.40 1.47 1.53 1.40 1.30 .37 It should be imderstood, however, that these quantities need not neces- sarily be adhered to, but that they may be varied according to necessity or taste so long as the nutritive standard is approximated. It is not a question of the special articles of food employed nor of the amounts in which they may be used, but is rather one of the total quantities of protein, fats and carbohydrates yielded by the entire amount of food eaten during the twenty- four hours. By referring to the analyses of the articles of the ration given on pages 161 and 162, the nutrient value of any combination, in variety and quantity, can readily be calculated. , Drink. — Coffee, if not too strong, may be taken freely in the tropics; tea should be used sparingly, as when improperly made it has a directly retarding effect upon the digestive function. In a few instances in the Philippines, weak tea and coffee, cooled in porous jars, have been kept con- stantly on draught in lieu of drinking-water. Acid drinks are much craved, but their use should not be too long continued as inducing dyspepsia and intestinal disturbances ; and the same may be said of the milk of the green cocoanut. The presence of an abundant supply of piue water is an essential in the tropics, and it is not a refinement of caution to insist that, under aU cir- cumstances, water supplied for drinking should be sterilized by one of the methods already described. Eecently, in one military department, in the Philippines, the use of unboiled drinking-water was forbidden and the employment of water of this character regarded as disobedience of orders 886 THEOEY AND PEACTICE OF MILITARY HYGIENE. and treated accordingly. To assist in carrying this order into effect, a system of daily inspection of drinking-water and canteens was established. Precautions of this character, for ensuring good quality, cannot be regarded as excessive in a matter of such importance. If water be drunk rapidly and in large quantities, it passes into the intestine without being properly subjected to the germicidal action of the gastric juices, and hence permits the introduction of ' pathogenic micro-organisms, in viable condition, into the more favorable habitat of the bowel. Further, it dilutes the intestinal juices and impairs their activity. The temptation in the tropics is to drink too much and too often. This relieves thirst but temporarily, increases perspiration, adds to the discomfort and is prone to iaduce gastro-intestinal disorders ; hence, it is well to form the habit of rarely drinking between meals — this being readily acquired by force of wiU. It is important to remember that it is not so much the rapid introduction of fluid into the stomach which allays thirst as its gradual passage over the back of the mouth and fauces. For drinking purposes, too warm water is nauseating and has no direct influence upon the reduction of body-heat. Hence it is important to cool the drinking-water, and this may readily be accomplished by placing it, preferably after sterilization, in porous earthenware jars, canvas buckets or suitable receptacles wrapped in linen, felt or other suitable material which has been wet, and swinging the same in a current of air, preferably in a window or under a tree, the contents being cooled by surface evaporation. Where ice is available, it may be more conveniently used to lower the tem- perature of the drinking-water, but a pleasant degree of coolness can always be readily obtained by the method just given. Iced water, when used in excess, has a tendency to benumb the mucous coat of the digestive tract and largely diminish its powers of absorption for the time being; but cold water is never dangerous if drunk slowly or taken in small quantities, even if the individual be greatly over-heated. Its iU-effects lie wholly in its abuse. Artificial Refrigeration. — The lack of ice and of cold-storage facili- ties is a want most keenly felt by all natives of cold countries transported to the tropics, and their presence conduces much to the health and comfort of this class. Particularly is this the case with regard to the sick, in the proper treatment of whose diseases, notably sunstroke and typhoid fever, the use of ice is often essential. Formerly difficult to obtain, the natural product was carried in vessels from colder climates ; but now ice may be artificially manufactured at any point in the tropics, and at slight cost, by the simple application of a few elementary physical laws. At present there are a large number of forms of apparatus for the production of artificial re- frigeration, but the operation of all are dependent upon the fact that heat is necessary for the expansion of gases, and that this heat is abstracted from bodies with which the gas, at the time of expansion, is in close relation. The principle of the De La Vergne refrigerating system is extremely simple, and may be looked upon as a type of the ordinary apparatus in com- mon use. Ammonia-gas and oil are received into a compressor from which they are discharged together into the oil cooler. The cooled oil drops into the first tank while the gas continues into the condenser, where it is lique- fied and collects in the second tank. The liquid ammonia is taken off from a point near the top of the second tank. A little oil is taken over from the THE HYGIENE OF HOT AND COLD CLIMATES. 887 condenser and is conveyed by a pipe, as shown in the accompanying dia- gram, to a point near the bottom of the second tank, where it remains ; since it is heavier than liquid ammonia and cannot rise to get rato the liquid pipe of the ammonia supply. The liquid ammonia is then passed through the expansion-cock into the expansion-coil, where it volatilizes into ammonia vapor, which is drawn off into the compressor to pass around again in the order described. The Condict system, in utilizing the heat-absorbing qualities of am- monia, takes advantage of the strong affinity which this gas has for water — ^the latter being employed merely as a carrier. Advantage is also taken of the fact that ammonia-gas, having taken up a given quantity of heat, will, on its being absorbed by water, give it out again. The operation of the system depends on the generation of anhydrous ammonia-gas from aqua ammonia in a retort by means of heat direct from steam. The heat is then removed from the gas by condensing or liquefying it in suitable coils of pipe by lowering its temperature by means of running water on the outside of the COOLINO VWTCR. ^ ' "^ 'j 1 H H 1 H I U I 1, ' I EXPANSION COCK. Fig. 373.— Diagram of De La Vergne Relrlgerating System. coils. The liquefied ammonia is then admitted through a small opening in a valve iato other coils of pipe. Here, because of the reduced pressure, the amcmonia assumes the gaseous state, taking up heat in the process from the surrounding material and producing the desired refrigeration. Having taken up its necessary quantity of heat, the ammonia-gas passes into a suit- ably designed receptacle known as an absorber and is quickly taken up by the weaker aqua ammonia, delivered through a valve from the retort where the gas has originally been driven off from it. Here also the heat, which the gas has taken up in the expansion-coils, is given out by virtue of the union of the weaker aqua ammonia with the gas ; and the heat so given off is carried away by the cooling water which circulates through the tubes of the absorber. Having disposed of its heat, the ammonia is now ready to be returned to the retort and the cycle repeated. This is done by means of an ammonia feed-pump which receives the strong aqua ammonia from the absorber and delivers it to the retort ; the aqua or water ammonia thus acting as a carrier of the ammonia-gas. For the utilization of the cold produced in the two systems above de- 888 THEORY AND PEACTICE OF MILITAEY HYGIENE. scribed, two methods are in use. In the first, the ammonia expansion-coils are placed in a tank filled with a saturated solution of common salt in water, this not freezing at a temperature as low a*s that of zero. This brine gives up the heat necessary for the expansion of the ammonia and thus its temperature is continually lowered, the quantity of heat lost naturally de- pending upon the amount of ammonia admitted to the expansion-coils. To apply practically to refrigerating purposes the cold stored in the briae, the fluid is pumped through coils of pipe placed in the apartment to be refrig- erated — ^the process being analogous to that of heating rooms by steam — and is finally returned to the brine-tank to be again cooled. In the second system, the expansion-coHs, instead of being placed in a tank, are run di- rectly into the room to be refrigerated ; the ammonia taking up from the air of the apartment the heat necessary to its conversion into the gaseous state. Steam'Pipes no. 373.— Condict KelrigeraHng System. The Allen dense-air ice-machine is somewhat different from the fore- going forms of apparatus, in that it uses no ammonia and produces cold by the expansion of ordinary atmospheric air which has been previously com- pressed and then cooled by circulated water. Starting with air under about sixty pounds pressure, it compresses the same to about two hundred and ten pounds pressure, and in this state it is cooled in a coil immersed in water ; and then by an expanding engine the air is brought back to sixty pounds pressure, with resulting low temperature. The cold air is then led through pipes into the brine-tank and, if necessary, may subsequently serve to cool a refrigerating-room, being returned to the suction side of the air- compressor of the apparatus. The machine is particularly applicable to pur- poses where no great amount of ice-making or refrigeration is necessary, and is much used on board ship. It is extremely simple and compact. The various forms of refrigerating machines are compared by the effect they produce equivalent to the melting of a corresponding amount of ice. The melting of a pound of ice is equivalent to the absorption of one hun- THE HYGIENE OF HOT AND COLD CLIMATES. 889 dred and forty-two vmits of heat, the heat-unit being the amount of heat necessary to raise one pound of water 1° F. ; but in making ice from water more than one hundred and forty-two heat-units must be removed, since, whatever be its original temperature, the water must be reduced to 32° F. before ice can be produced, and, in addition, ice cannot be made with econ- omy without going to a temperature much lower than the freezing-poiat. Further, this proportion is still reduced by the iuevitable losses attending the use of large freezing-tanks and the handling of the product. Hence the amount of ice actually produced is by no means as great as the theoretical refrigerating capacity of the apparatus, and for all practical purposes is not usually considered to be greater than one-half. Water is usually converted into ice by mechanical refrigeration through 'one of two ways — ^namely, "by the so-caUed "can" and "plate" systems. Fig. 374.— Allen Dense-air Ice-machine. A^ Steam cylinder ; B, air-compressor cyUnder ; C, water tank and cooling pipe ; J), expander cylinder ; E, oil trap. In the former, the fluid to be frozen is placed in galvanized iron cans, which are immersed in a tank of strong brine. The temperature of the latter is maintained at about 10° F. by the expansion of the liquefied ammonia or compressed air in coils of pipe submerged in the brine which surrounds the can. The low temperature of the brine causes the water to give up its heat ; the ice being first formed on the sides and bottom of the can and the center being the last to become solid. The cake of ice thus made is loosened from the can by dipping the latter into tepid water. Because of the continual sep- aration of whatever impurities may be present in the water, and their con- centration in the center of the ice-cakes, by the action of freezing, it is essential that all impurities be removed from the water before congelation. This is best done by distillation or long-continued boiling; the process ex- pelling the air and thus rendering the ice not only sterile but also transpar- ent. The latter is a quality which cannot be obtained with the use of ordinary water except by its constant agitation or rapid freezing, and then only in part. In order to economize in fuel, it is desirable to condense the exhaust-steam from the engine into water for the purpose of ice-making, 890 THEORY AND PEACTICE OF MILITAEY HYGIENE. and for most forms of apparatus this steam has to be freed from the oil used in lubricating the steam-cylinder. This is accomplished by simple steam- filters, and after condensation has occurred the water is again filtered in order entirely to deodorize it. Can-ice thus made contains but a small amount of porous ice in the center — the latter being due to re-absorption of air during freezing — and is not only clearer and purer but also more durable — Double 1 Inch Matched Sheathing Pappr Between — Air Space Double 1 inch Matched Sheathing Paper Between — Air Space ^^^^^t "* Double 1 Inch Maluhed Sheathing Paper — Air Space Fig. 375. — Insulation for Main Walls, Wooden Ice-bouse or Cold-Storage Room. than ordinary natural ice. The period required for the freeziog of a can is usually about sixty hours. In the " plate " system, the ice is frozen direct on plates fastened to expansion-coils submerged in the water. The ice builds up on the plates until it reaches a thickness of about one foot, when it is released by circulating warm gas through the coils and thus melting it off; the plate of ice is then lifted out of the tank and cut into suitable sizes for handling. The mass of ice thus made usually weighs about a ton and requires about ten days for its production. A third method of making ice consists in the use of stationary cells, having hoUow walls through which cold brine is pumped. It is evident that in this method, as with the plate system, a whole tank has to be emptied at the same time, and, to make the plant continuous in operation, more than one tank has to be employed. With the can system, on the contrary, there is no loss of time or cold, and the blocks of ice can be taken out of the brine-bath, and cans filled with fresh water set in their places, without interrupting the operation of the whole. The principles employed in the manufacture of ice are also utnized for the cold-storage and preservation of perishable articles. The chiR-rooms, properly insulated, are provided with an overhead arrangement of pipes through which cold brine is pumped or with a coil for the direct expan- Double 1 inch Flooring Paper Bctveea 2 iuch AlrSpKce 1 Inch SbeaUiiDg with Paper 2 inch Air Space 1 iDCb Stie&ihing with Paper Double I inch Ualche£ PIiMring'Pepsr Bctweea sion of ammonia or compressed air. This system of mechanical refrigera- tion is far superior to the use of ice, since not only can a lower temperature be maintained if desired, but atmospheric moisture is promptly condensed on the refrigerating pipes ; thus giving not only a cold but dry atmosphere and rendering unnecessary the wasteful and unpleasant practice of trim- ming refrigerated meats before their use. Wliile exact temperatures can- not be given for the preservation of all foods to the best advantage, it is sufficient to say that beef and other meats, vegetables and fruits are well THE HYGIENE OF HOT AND COLD CLIMATES. 891 Double I locti Uuched SIieulilDg I^per 4 iDcb Air Spu« Double 1 incb Uaicbed SbeuUng rspeC 3 locb Air Space Doable 1 \B«i Uudud Sheathing Paper kept at about 35° P., and only a few articles, such as butter, cheese and poultry, are best preserved by a temperature below the freezing-point. The maintenance of cold below 25° F. is always undesirable — except in the case of meats which are to be sent long distances in hot weather, and which are preferably frozen solid before shipment. Few investments in connection with the use of artificial refrigeration are more profitable than money expended on securing good insulation, since otherwise a large proportion of the available energy is lost in overcoming the effects of heat transmitted through the walls of the plant. To prevent this loss, there should be an air-tight surface toward the source of the heat and insulating strata toward the cold side of the wall. It should be re- membered that air is one of the best non-conductors of heat, provided it be kept still ; but if allowed opportunity to form currents it wOl convey a large amount of heat from the outer to the inner wall, since rapid move- ment results when air is free to move between walls differing even a few degrees in temperature. The meth- od of securing insulation is shown in the accompanying diagrams. The filling-in of the interspaces with loose non-conducting material is un- necessary and possesses certain dis- advantages. The penetration of air and moisture should be specially guarded against by the use of pitch in connection with buildings of brick or stone; or of paper when wood is used. Whatever the mate- rials chosen for purposes of insula- tion, they should be free from un- pleasant odor and be non-absorbent. In securing insulation in wooden buildings, all joints should be laid in white lead and the insulating paper should be carefully folded and laid so as to overlap. Since the flow of heat is nearly proportional to the difference of temperature between the inside and outside waU, this fact must be given fuU consideration in arranging insulation, for what is sufficient for a refrigerator or cold-storage room in a fairly cool climate would be totally inadequate in the case of a freezing-room in the tropics. Clothing. — -This, in the tropics, should not only protect from the rays of the sun, as well as from chilling, but should favor the evaporation of sweat and the dissipation of body-heat. It should be light in both weight and color, but should not be too thin, as a certain amount of substance in military clothing is desirable for durability and protection of the person against traumatism. While to have all garments of wool would be unreasonably oppressive, an entire cotton dress would be dangerous for men liable to the sudden exertions of mOitary life, and it is probable that the combination of thin cotton outer-garments with Kght woolen underclothing is best for the tropics. As the temperature in the tropics undergoes but Fig. 377.- -Door for Cold-Storage Eooms and Ice- houses. 892 THEORY AND PRACTICE OF MILITARY HYGIENE. slight variation during the year, no change in the weight or texture of the clothing is required for different seasons. For field service, the color selected for the uniform should be a light dusty-brown, as being best calculated to conceal the discolorations produced by hard service and also being less absorbent of solar heat. Such a color is, however, less inconspicuous than under the ordinary conditions of environ- ment as found in temperate chmates, since the prevailing color of vegeta- tion in the tropics, throughout the entire year, is green rather than brown. Theoretically, from, the standpoint of conspicuousness on the firing line, the field uniform for the tropics should be of a shade obtained by blending a light green and brown ; but the comparatively slight advantage of such a color over the present light brown would seem to be counterbalanced by the undesirability of requiring an aheady overworked supply department to provide special uniforms for the tropics, the color of which for troops re- moved to other surroundings, as for this country or during the late expedi- tion ia China, would be much less desirable than that now in use. For garrison duty, uniforms of white cotton ducli may be issued — a more showy combination for parades being white helmets and trousers and thin blouses of dark blue serge. White, however, has the great disadvantage of soiling readily and presenting a bad appearance without constant washing. This latter defect was avoided to a considerable extent in the uniform of white striped with light blue, used by the Spanish troops on tropical service. In cut, clothing should be very loose to permit of the ready renewal of the layer of air in contact with the body and the lowering of temperature through facilitating evaporation of persphation. There should be perfect freedom of action in respect to the body and limbs. The collar of the blouse should turn down ; the handkerchief, if necessary, being tied around the neck for its protection. All folds and reduplications of cloth, except a central pleat down the back of the blouse, should be avoided. The latter may serve a useful purpose in giving additional protection to the spine against the solar rays and thus assist in guarding against sunstroke. In cut, the present khaki uniform is admirable ; but the blouse may be improved by working ventilating holes in the arm-pits to allow the more free entrance of air. The khaki cloth at present used in the field tmiform is cheap, and obviously possesses many excellent qualities for the purpose for which it is employed. Though much lighter than the blue uniform cloth, it is, how- ever, somewhat too heavy and dense for comfort, and is so tightly woven as to interfere seriously with the passage of air — more so than would be the case with light serge. These very qualities of heaviness, smoothness of surface and close texture, however, confer a durability which is of the great- est value during hard field service. For securing this durability, it is im- portant that the cloth employed should be of the best grade attainable ; since transportation is a most serious problem in the field, tod with widely scattered forces the distribution of new clothing is often slow and difficult. A better quality of clothing means that the soldier can march with a lighter supply, and that the latter need not be renewed as frequently. No eco- nomical advantage ultimately results from the issue of articles of inferior quality, and such action may also be productive of hardship to the soldier through the wearing out of his garments under hard service at a time when their replacement is a matter of the most difficulty. Khaki uniforms should THE HYGIENE OF HOT AND COLD CLIMATES. 893 be issued in a standard grade, since, after washing, shrinkage at present not only occurs but the material made by different manufacturers assumes a variety of colors, from almost white to brown. The torrential rains of the wet season render the use of water-repellent clothing essential, and for this purpose all outer clothing issued to the soldier should have been water- proofed with lanohn or acetate of aluminum by the methods referred to elsewhere. The ilannel shirt is an ideal garment for military use in any climate. For tropical service it is superior to the chambray shirt, now issued, but should be made of light-weight material and should be dyed a brown color to correspond with the khaki uniform. The general tendency among troops at present is to wear the blue flaimel shirt and khaki trousers in place of the chambray shirt and khaki blouse and trousers. The undershirt is rarely worn with this garment during the day, but is sometimes donned at night to protect the skin from the irritating contact of the flannel. The use of the flannel shirt at night gives excellent results in preventing chilling of the abdomen. It is of interest to note that the Italian soldiers at Massowah, in 1885, simply bound a strip of cloth around the body in lieu of a shirt. All elastic substances soon lose their elasticity in hot climates; and elastic braces in particular, being continually sat- urated with perspiration, rapidly become stretched and unserviceable. For tropi- cal service, suspenders are thus advanta- fig. 378.— summer Helmet, geously made of cotton webbing. It is particidarly necessary in the tropics that the use of all confining waist-belts and cross-straps should be avoided. While the head-gear is of great importance in all climates, it is of the first interest in the tropics ; since the head is the part which is at the same time the most sensitive and most exposed to the rays of the sun, and with its proper protection sunstroke is largely avoided. The head-gear should be large, light in weight and color, and should permit free circula- tion of air and afford protection against sun and rain. It should not only shade the eyes but should also protect the back of the neck. In the French and English colonial services, the cork helmet, covered with light gray or brown cloth and with visors lined with green, is worn during campaign. In our own service, the white helmet is used only for parade or garrison duty ; but a special khaki-covered helmet has been issued to certain volun- teer regiments in the Philippines. The white helmet is composed of two thicknesses of cork, laminated and cemented together with sheUac. The sweat-leather is on a frame hoop, weU separated from the shell, for purposes of ventilation, by small corks securely fastened in place. Ventilation at the top is assured by an adjustable ventilator. The helmet is covered with cotton drilling and weighs 6.8 ounces when finished. In the French and English colonial services, the so-called puggarees are worn, but these are inconvenient on horseback, particularly when riding fast. Dtiring the British campaign in the Soudan, cork helmets were used and each man was supplied with a veil. Pith helmets are useless in a wet climate. Like 894 THEOEY AND PEACTICE OF MILITAEY HYGIENE. the light white helmet issued in our service for garrison use, they soon become sodden with rain, lose their shape and fall to pieces. Straw hats, as worn by the Spanish troops, are an excellent protection against the heat and are light and inexpensive. They are, however, readily crushed and broken and soon become worthless in wet weather. For service where a change of hats cannot be made, the campaign hat is the only head-gear which has fully answered all purposes. When provided with a separated sweat-band and with large ventilators of wire-gauze in the sides, if thor- oughly waterproofed with lanolin and worn with a pointed peak, it affords sufficient protection against the sun, perfectly protects against the raiu and is much more comfortable and useful at night than is the helmet. Without waterproofing, this hat soon breaks down and becomes unfit for use during the rainy season. During the very hot hours of the day, the wearing of a wet handkerchief, leaves or grass inside the crown of the hat may some- times be of service in adding to the protection against the solar rays. Next to the head it is the abdomen which, in the tropics, especially re- quires protection. This, in our service, is well afforded by the flannel shirt and drawers worn by the soldier, and hence recourse to the abdominal bandage, held in such high esteem in the British and French colonial ser- vices, is unnecessary. However desirable such an additional protection may be in time of cholera or diarrhoeal epidemic, the value of its general use in the tropics may seriously be questioned. To march on a hot day with such a band over the abdomen is evidently illogical, since it increases the temperature and weakens the powers of resistance, thus perhaps even predisposing to the diarrhcBa which it was intended to prevent. The na- tive West Indian troops of the British army wear a species of zouave uni- form, the trousers of which are cut unusually high in the waist and so afford an excellent protection to the abdomen. In India, putties form part of the military uniform. They are worn over the trousers and give support and protection to the legs, but appear to possess no advantages over the regulation canvas legging of our service, besides being more difficult of adjustment. Cotton stockings are probably best for wear in the tropics, though some prefer those of light wool for marching. The present style of russet shoe, on the whole, appears to give satisfaction for tropical use ; but it is questionable if a well-made canvas shoe, with heavy leather toe-cap, would not be preferable. It is of par- ticular importance that shoes should be well-fitting, since abrasions of the cuticle of the feet are a special source of danger in the tropics through the constant opportunity for their infection by the agents producing tropical ulcerations. Eubber-boots should be supplied to guards during the rainy season. Shelter. — The same general principles for the selection of the site for camp or barracks in temperate regions, already given, apply with even greater force in tropical climates — inasmuch as the question of malaria enters so largely into all considerations — and it is of the greatest impor- tance that military preferences should not be permitted to outweigh evident sanitary defects of site. In general, garrisons should be established on high ground, where the temperature is lower, the air fresher and the soil dryer and more healthful. On the plains, malarial fevers are prevalent, humidity — the great enemy of the white race — is greater and the chemical changes THE HYGIENE OF HOT AND COLD CLIMATES. 895 in a damp and overheated ground go on more rapidly. The difference in temperature between day and night is always less on the plains than on higher ground. From military necessity, however, it is not always pos- sible to select an elevated site, and under such conditions a comparatively unhealthy station must usually be expected. StOl, much in the way of im- provement may be accomplished, particularly iu the special relation of the site to malarial marshes, its thorough drainage and the removal of too dense or rank vegetation. Herbage, kept closely trimmed, should be cultivated in the vicinity of barracks in the tropics to lessen the glare and the reflection of heat. The site should be selected so as to receive the fuU effect of the sea-breezes or prevaUing winds ; the immediate vicinity of large cities being avoided. An obviously unhealthy station should unhesitatingly be aban- doned, after intelligent efforts at its improvement have been made, as being more economical of both money and lives. The orientation of barracks in the tropics should be such as to present the least surface to the more direct solar rays, and hence the long axis of the building should be east and west; this rule, however, may often be changed in order to take advantage of prevailing winds. All buildings should be widely separated and should be erected en echelon, for better exposure to air-currents. In the British service, the minimum distance be- tween barrack buildings is fixed at sixty feet. The general plan of the British barracks in the tropics is a pavilion having an entrance at the middle with a squad-room on each side, the latter separated from the cen- tral hall by two rooms for non-commissioned officers. The lavatories and urinals are at each end, separated by short corridors from the main build- ing. The Spanish barracks in warm climates, and until recently those of the French service, are buUt in the form of a hoUow square. This plan, as aheady stated, is highly inadvisable imder any circumstances, and is par- ticularly so for the tropics, since it interferes with the free passage of air through the barracks and the resulting coolness. The construction of barracks for the tropics is a matter of the greatest importance ; many points having a practical bearing on this subject having been already discussed in connection with the construction of barracks for temperate climates. The material to be used for this purpose naturally varies with the antici- pated length of occupancy of the barracks. It should, in general, be of such a character as to prevent the transmission of heat and the absorption of at- mospheric moisture. For temporary habitations, wood is probably the best material, being easily worked and readily obtained and transported; but for permanent barracks in the tropics it should not be employed, since it deteriorates rapidly under the effects of heat, moisture and the attacks of insects. This material requires frequent attention and repairs ; and thus wooden buildings, originally inexpensive, are ultimately costly. In addi- tion, they soon become infested with ants, scorpions, rats and other vermin. Hard stone is the best material for permanent barracks ; but porous stone should not be employed because of resulting dampness of the walls. In de- fault of hard stone, kiln-dried bricks, painted on the outside, will serve — ^hol- low bricks being better as providing non-conducting air spaces in the walls. The roof should be of tiles rather than of wood or metal. Wood absorbs moisture and furnishes a convenient retreat for vermin, having also the ad- 896 THEORY AND PRACTICE OP MILITARY HYGIENE. ditional disadvantage of inflammability and the necessity of frequent re- newal. Metallic roofing is a good conductor of heat, and buildiags so covered are unduly hot. Tiles possess none of the disadvantages above mentioned and, through the manner in which they are disposed, offer nu- merous opportunities for the escape of heated air from the building. In the tropics, the use of double roofs, the intervening space being well ventilated, conduces much to coolness — and steeply sloping roofs rather than those which are nearly flat are preferable. Barracks should be of two stories and the upper floor alone used for living and sleeping rooms, the lower floor being devoted to storage and office purposes. If the building be a frame structure, it should be raised from the ground on piers to a height of four or five feet, and the area under- . neath the building and for a distance of several feet around its sides ce- mented or concreted. This concreted space, to prevent small animals and reptiles from taking up their abode under the buHdiiig, should be closed in with strong wire-net of narrow mesh, should be frequently policed and should never be used for purposes of storage. Where the barracks are of masonry, the lower floor should be eight or ten feet above the ground and the subja- cent space thoroughly cemented and ventilated. It is of course particularly necessary that proper means for the conduction of storm-water away from the foundations of the building be provided. Whatever be the material employed in construction, the walls should be double with a free air-space about eight inches in width between the two, and this air-space should have its own special ventilating apertures, properly protected, opening into the external air above and below. For masonry buildings, thickness of walls adds greatly to coolness. Lathing should be avoided ; plaster, where used, may be safely applied directly to the inner aspect of the double waE and thus afford less opportunity for the harboring of vermin. The walls and ceilings should be painted, a little coloring being added to prevent glare ; their corners should be rounded to facilitate cleansing, and the floors, if of wood, rendered impermeable. Floors of cement, vitrified brick or tiles are cool and desirable for hot climates. They are readily kept clean or disinfected and do not absorb organic matter or harbor vermin. The out- side color of the barrack should be cream, light yellow or pale blue to favor reflection of solar heat. Verandas and galleries, at least ten feet wide, should run the full length of each side of the building. These should have double roofs, properly ventilated, and be provided with jalousies or Venetian blinds ; since where verandas are open to the burning rays of the sun, the men are often unable to make use of them during the day and at night they afford no facilities for checking the direct admission of chilly air. Such screens are better fitted to the verandas than to the windows of the barrack-room, and should have movable blades so that they can be reversed to deflect the cool air upward and prevent any direct draft upon the men whQe heated by ex- ercise, disrobing or asleep. Doors and windows should be large. British army regulations for India require that there shall be one window for every two beds and five doors to each squad-room containing twenty-five men. Windows should be so placed as to oppose each other, to permit of more direct perflation, should be cut to the floor, and should be carried up nearly or quite to the celling to prevent the stagnation of the upper layers of air. THE HYGIENE OE HOT AND COLD CLIMATES. 897 They require no glass sashes, but should be fitted with heavy wooden shutters, sawn transversely in the center, for use in chilly weather. These shutters, however, should be controlled by non-commissioned officers, and their clos- ure, except as regards the lower halves, will not usually be required. Nothing in the shape of window curtains should be allowed. The ver- andas should be protected against flies and mosquitoes by being tightly enclosed with fine wire-gauze, and self-closing doors of the same material should be provided. All windows and doors not opening into such veran- das should be protected iii the same way. In the tropics, the native houses have no chimneys, but these are preferably placed in barracks. Fires will not often be required, but are occasionally grateful and an open fireplace does much to assist ventilation. The latter assumes a much greater importance in the tropics than in the temperate zone, since free change of air, besides that necessary for the dilution and removal of re- spiratory impurity, is of value for the lowering of temperature. In warm countries, however, the usual conditions of ventilation are reversed, since the interior of the house is often cooler than the outside; and, hence, for the proper renewal of the air, the use of the wind, in connection with aspiratory flues, must be largely relied upon. Large outlets, carried weU up above the roof and painted black, give good up-currents during the heat of the day. In cross-section, such shafts, irrespective of windows and doors, should present an area of at least one square inch for each twenty cubic feet of space to be ventilated. To ensure free circulation of air, it is im- portant that nothing be hung upon the walls — or, indeed, given space in the squad-room — except the bare equipment of the soldier. The regulations for the British troops in India provide that no more than fifty men are to be quartered under one roof, nor must the number of men in any one squad-room exceed twenty-fom*. Only two rows of beds are allowed in dormitories and these must be at least nine inches from the wall. But two beds can be placed in the space between two doors or win- dows and each bed must have at least 7.5 feet of running wall-space. Each man is allowed 90 square feet of superficies and 1,800 cubic feet of air-space. The height of the rooms is fixed at 20 feet and the width at 24 feet. For hospitals, the superficial allowance per bed is 120 square feet and that for air-space is 2,400 cubic feet. In considering these figures, it should be remembered that over-crowding in the tropics is more immedi- ately marked in its effects than is the case in temperate climates, and the sanitary officer must be constantly alert to prevent troops being too greatly concentrated for convenienc& of administration. The barrack proper should be an entirely distinct building and used merely for living and sleeping purposes. All latrines, wash-rooms, storehouses, kitchens and mess-rooms should be in small detached buildings placed to the leeward. The kitchens and mess-rooms should be well protected against invasion by flies. In tropical expeditions, from the usually wide-spread prevalence of communi- cable diseases, it is advisable to look upon native dwellings as dangerous shelters and avoid their occupancy. The air is both hot and stagnant in many parts of the tropics, and its artificial cooling and circulation is practiced in buildings. To meet these indications, the punkah, tattie and thermantidote are employed. The pun- kah, much used in the Orient, merely consists of a framework of wood and 57 898 THEOEY AND PRACTICE OF MILITARY HYGIENE. canvas having a fringe, this arrangement being swung backward and for- ward from the ceiling by a rope passing over a pulley and worked by hand. The thermantidote is a machine through which, by the rotation of a wheel and fans, a current of air is forced into a room. It has the great advantage of not only putting air in motion but also cooling it, through evaporation of moisture from thin, wet grass-mats suspended in the short discharge-channel through which it passes. The tattie, a loosely-woven mat of fragrant khus- khus grass, hung in the window, is much used in India in reducing the heat. The rapid evaporation of water sprinkled on such grass mats pro- duces a great fall of temperature in the room ; thus Fayrer states that, in Oude, with a hot west wind, the therinometer registered 104° F. in the shade outside the house, 83° F. in the house and 68° F. behind the tattie. Merely by sprinkling water on the floors the temperature of rooms may be considerably lowered. If the an- be dry, there is no difficulty in cooling the air by the evaporation of water to the extent desired. The evaporation of a gallon of water absorbs as much heat from the air as would raise 4.5 gallons of water from the freezing to the boiling point. As the specific heat of an equal weight of air is one-fourth that of water, it follows that the evapora- tion of one gallon of water will reduce 26,000 cubic feet of air from 80° to 60° F. If thoroughly utilized, 1. 5 gallons of water would be the per capita allowance for twelve hours, but as theoretical results are rarely to be attained in practice, this quantity will usually have to be doubled. In large cities in the tropics, these primitive methods of securing coolness will usu- ally give way to the use of rotary fans driven by steam or electrical power. At stations not directly connected with an electrical plant, small fans, run by a storage-battery, may be employed in hospitals. In this connection it may be mentioned that barracks, in the tropics, should preferably be lighted by electricity ; thus securing an excellent light without the production of any great amount of heat or vitiation of the atmosphere. It may be laid down as an axiom that, in the tropics, troops should not be encamped under canvas if more substantial shelter is available. While with the improved tentage devised by the writer the question of tempera- ture and ventilation may be regarded as satisfactorily solved, the necessity of living and sleeping close to a moist and fermenting soil, without ade- quate protection against the attacks of insects, greatly favors the occurrence of typhoid and malarial infection. In the Philippines, it has not rarely happened that where troops were forced to bivouac even for a single night on damp or wet ground an immediate and very perceptible increase of the sick-list has been noted, Hence it is that a poor barrack, if fi-ee from the infection of disease, may be regarded as preferable in the tropics to the best of tents. For service in hot climates, the United States army regulation tentage is seriously defective and is extremely hot and close under the vertical sun and in the humid atmosphere of the low latitudes. This fact was commented upon by the inspector-general in his report upon the condition of troops in the "West Indies in 1899, and the following comparison of temperatures was made by him in southern Cuba : Hospital — Brick building with tile roof 84° F. Offiqel's' Quarters — Wooden building, tile roof, windows shaded 88 THE HYGIENE OF HOT AND COLD CLIMATES. 899 Barrack — Wooden building, thatched roof 85 Barrack — Wooden building, zinc roof 86 Common tent, without floor 94 Hospital tent, with floor 95 Conical-wall tent, with floor 102 These figures showed a difference of eighteen degrees of heat hetween a hrick building and conical-waU tent. On reflection, it appeared to the writer that this excessive heat in the tents, particularly the hospital tent, was due : (1) To the impingement of the direct solar ^ays upon the single thickness of canvas of the walls and ends. (2) To the insufficient air- space and limited opportunity for the movement of air between the fly and roof of the tent. (3) To the inadequate size and improper location of the openings for ventilation. The writer therefore recommended: (1) That the tent-fly be enlarged two feet in length and four feet in width. (2) That this fly be raised upon a light false ridge placed one foot above the FIG. 379.— Munson Hospital Tent, Front View. present ridge, the latter being removed and replaced by a. rope. The up- per ridge to be four feet longer than the ridge of the tent proper and to project two feet to the front and rear. (3) That the canvas comprising the top of the tent be cut out for a space two feet wide on each side of the ridge and running the entire length of the tent — except for one foot front and rear. (4) That the tent fly be of white canvas better to reflect the heat rays, while the tent itself be made of drab canvas, properly to subdue the light in the interior. The above changes ensured complete protection of the waUs^and nearly so of the ends — from the rays of the sun ; a large free space, at least one foot wide, between the tent roof and fly, from which the heat is readily driven by perflation ; and finally, complete ridge ventilation of the tent itself, rendering the stagnation of heated or impure air impossible. As at present arranged, this hospital tent has forty-eight square feet of ventilating surface where the regulation tent has less than two-thirds of one square foot ; and not only does heated air directly escape through this openiiig but currents of air passing horizontally over the netting under the fly exert a 900 THEORY AND PEACTICE OF MILITARY HYGIENE. direct aspiratory effect on the air within the tent itself. The two-foot overhang of the fly, front and rear, implies the pitchiag of the hospital ward in tent sections four .feet apart ; the sheltered iatervening spaces al- lowing free lateral ventilation, the complete isolation of patients, direct en- trance and egress of the inmates without the necessity of passing through other tents of the ward, and finally, a covered area for the protection of ward property. The temperature of the improved tent was carefully com- pared with that in an adjoining hospital tent of the old regulation pattern Fig. 380.— Munson Hospital Tent, Side Elevation. and the new model conical-wall tent, and the temperatures in dense leafy shade and in the sunshine also noted. The thermometric readings were as follows : Time o day. ■ In the direct rays ol the sun. In the shade of a leafy tree. Munson tent. Regulation hospital tent. Conical-wall tent. Remarlis. 1... 2... 3... 11... 12... 1... 3... 3... 87.0° 94 90 95 97 103.5 104.5 93 79.5° 80.5 83 84 88 88.5 93 88 84.0° 86 86 89.5 93 90.5 90 89 89.0° 94.5 93 99 97.5 96 94 92 93.5° 100 97 107 106.5 98 93.5 91.5 Tent walls down. u u u U it u U U U Tent walls rolled up. U li ii These figures show a temperature in the improved hospital tent, with walls down, never more than 5.5° F. higher than in dense shade in the open air and once only 3° F. higher. As compared with the regulation hospital tent, the temperature of the improved tent averaged 87.5° for the latter and 94.5° for the former — an average difference of 7° F. On one occasion, a difference of 10.5° F. was noted. As compared with the conical- wall tent, the temperature ranged from 9.5° to 18.5° lower in the improved tent. It was observed that this tent, with walls down, was only two or three degrees warmer than with walls rolled up — a point of especial value in connection with the treatment of the sick, where the subdued light and comparative quiet and seclusion of the closed tent are desirable. This tent can be made warm and snug for any climate or sudden change of weather by means of a canvas flap, attached to the tent roof by one border, by which THE HYGIENE OF HOT AND COLD CLIMATES. 901 the ventilating opening can be readily closed. This tent has been of&ciaUy adopted for use in the military service of the United States under the name of the "Munson hospital tent." The writer also recommended, for tropical use, that the present conical wall tent be provided with a fly, shaped in the form of a truncated cone, having a diameter at its base two feet greater than that of the tent, and sup- ported from a large ring and the center pole, the same as the tent itself. The length of the fly should, of course, be a trifle greater than the canvas of the present tent, exclusive of its wall. This modification has also been shown materially to reduce temperature and promote ventilation. To in- crease ventilating action further, the opening of the apex of the fly is made the same size as that of the tent ; the heated air rising between the tent fly and the tent roof exerting an aspiratory effect on the air within the tent as it passes over the ventilating opening in the latter. The apex opening of the tent is closed during stormy weather by the movable cap as at present used, the latter being manipulated by ropes passing between the tent roof and the The common wall tent, on account of its small size and lack of fly, is totally unsuited for use in hot climates. Troops who must live under can- vas in the low latitudes can be comfortable only when quartered in the improved tents, just described. Where tents of these models are not ob- tainable, a certain degree of relief from the heat may be obtained by pitch- ing one wall tent inside of another, spreading additional flies and supporting their comers away from the tent roof, or by erecting a frame over the tent and covering it with green branches. Where the old style tents are used during hot weather or in the tropics, they should contain only half the num- ber of men they are officially expected to shelter. With the writer's im- FIG. 381.— Mtmson Hospital Tent, Side Elevation, Fly Thrown Ba«k. proved tents, on the contrary, the ventilation is so free that the inmates are practically in the open air, and hence an even greater number than the au- thorized allowance may be eomfortably accommodated. On marches or campaign, particularly in the rainy season, the shelter- tent will prove the most valuable article of the soldier's equipment. Wher- ever possible, the men should be instructed to raise rude scaffolds and by pitching the shelter-tents over these to raise their bodies well off the groimd. In their effort to reduce weight, however, our troops in the Philippines have not rarely discarded even the shelter-tent halves during active field service. Where shelter-tents are not available, it wiU be rare that fairly waterproof 902 THEORY Al^D PRACTICE OE MILITARY HYGIENE. "lean-to's" or sheds cannot be quickly constructed from palm branches, grass or bark. Sleep. — Wherever it can possibly be avoided, soldiers should not be permitted to sleep upon the ground. If this be necessary, the poncho should be used to protect from dampness, but it will usually be possible to raise the body above the ground on extemporized platforms. For tropical use, the regulation woven-wire cot is inferior to one made of bamboo with a closely woven wicker top. The latter possesses sufficient elasticity to be comfortable even without a mattress, allows the passage of air and thus keeps the occupant cooler. For camps, the folding canvas-cots, previously described, are of advantage. If mattresses are used, they should be of shuck or hair and not too thick. Feather pillows should not be employed. As the nights are often chilly, one or two woolen blankets should be available. The use of the mosquito-bar is essential in the tropics. Apart from the irritability and loss of rest produced by the nightly attacks of these iQsect pests, their bites are now recognized as being a means for the trans- mission of malarial infection and yellow fever, and are frequently the startiug- points of intractable ulcerations or painful pustules. The net should have a mesh sufficiently fine to keep out gnats as well as mosquitoes — that of the mosquito-bar supplied in oar service being much too large for the former purpose. The use of pajamas as a sleeping-suit is advisable; this practice being cleanly, comfortable in hot weather and especially valuable as not permit- ting an tavoluntary exposure of the abdomen or body while asleep. In India, the use at night of a broad woolen sash or cummerbund, wrapped tightly around the outside of the cotton pajamas, is much favored. This special protection is more necessary from the fact that during sleep the physical power of resisting cold is much diminished ; and not only is chiLL- ing more liable to occur, but its effects are more severe than would result from a similar exposure during the waking hours. For this reason, the practice of sleeping in a draft or the open air, for the sake of greater cool- ness, is to be deprecated. In the tropics, the siesta is almost a necessity. The intensity of the sun, in its directness, requires that the middle of the day be spent quietly within doors, and during this period the men should not be allowed to leave the barracks. There is no doubt but that sleep during the day somewhat interferes with digestion and favors wakefulness at night, and hence it would appear logical to avoid sleeping dm-ing the day in the absence of unusual fatigue or prolonged lack of repose. On the other hand, it appears to be true that residents in the tropics require more sleep than those who reside in temperate regions, and that, as a rule, nine or ten hours out of the twenty-four should be given to its attainment. Frequently, also, the siesta taken in the middle of the day is more restful than the fitful slum- bers of a stifling night; and repose, while itself of advantage, also affords a pleasant way of passing hours in which but little can be accomplished. The actual duration of the siesta should not exceed one to one and one-half hours. Work and Exercise. — For the white race, the great heat of the tropics precludes the possibility of doing as much work as in a temperate climate ; to attempt it is to invite disaster — for the limit of strength and endurance THE HYGIENE OF HOT AND COLD CLIMATES. 903 is soon reached under tropical conditions, and lowered vital resistance through fatigue is especially a potent cause of disease. The production of internal heat by muscular exertion is a matter too frequently overlooked, Foster stating that nine-tenths of the energy required for a muscular con- traction is expended in the form of heat and only one-tenth is represented by the work accomplished. Without condemning the troops to absolute idleness, the work to be performed by them should be reduced to the limits of strict necessity, and scavenging and other hard labor, particularly that which must be performed in the heat of the day, should be done by na- tives. Under no circumstances should work be done in the direct rays of the sun, between 11 a.m. and 3 p.m., and labor implying disturbance of the soil should preferably not be performed by white troops. It should not be understood, however, that tropical service and physical exercise are incompatible. It is true that the tendency in hot climates is toward a sedentary life and that indolence is a direct result of the relaxed muscular and circulatory systems, but this tendency on the part of soldiers must be combated in the prevention of physical retrogression and mental apathy. Exercise should not, however, be overdone ; and the time for its performance should be carefully regulated. Tlie morniug, a short time after breakfast, is the best part of the day for its accomplishment. Motion, even the most moderate, is always attended with profuse perspii'ation ; and men who expose themselves to the cool air of night-fall in this condition, with wet shirts upon their backs, are prone to chilling and resulting sick- ness. After morning exercise, however, the heat of the day follows and prevents any evils of this character. It is true that bad effects might be avoided were the men to put on dry shirts after the evening exercise — but to do this is not always an easy matter for the soldier. Exposure to drafts while perspiring is always to be avoided. Marching. — This, as far as possible, should not be performed in the rainy season, and shoidd be suspended duriiig periods of the greatest heat. Night marches slujuld be as carefully avoided as those of mid-day. In general, marches should be performed from 5 to 9 a.m. and 4 to 7 p.m. ; the men resting during the heat of the day. French colonial regulations allow no marching for infantry between the hours of nine and three — cavalry being allowed to march until ten o'clock. As far as possible, marches should be so timed that the rays of the sun do not fall on the backs of the men, nor should they ordinarily be allowed, to exceed ten or twelve miles. In malarious regions, especially, the length of marches should always be reduced to the minimum if the malarious district is too large to be crossed in one or two long marches. Eapidity of marching is undesirable except under stress of military necessity. Siace exertion and fatigue are great factors in the production of sunstroke and in the occur- rence of disease, it is important that the equipment and burden to be carried by the soldier should be lightened as far as possible. For this purpose, the employment of native porters is usually necessary. The ordinary load for native carriers is from 40 to 80 lbs. ; two carriers being estimated to trans- port as much as one mule. British soldiers, in the tropics, carry only their arms, ammunition and canteens, and the remainder of the equipment is transported by carriers. In the Soudan expedition of the British, the number of porters accompanying the column equalled that of the combat- 904 THEORY AND PRACTICE OF MILITARY HYGIENE. ant force; while on the march from Cabul to Candahar, in 1880, with 10,148 troops there were 8,143 native followers and 11,224 transport ani- mals. In the Dahomey expedition of the French, the weight carried by the soldier amounted to about 32 lbs. ; the remainder of the equipment, weighing 30 lbs. per man, being transported by carriers. The native soldier of the French colonial army, however, is required to carry his own complete equipment, the weight of which is about 60 lbs. Frequent rests should be given at suitable points during the march, the men being especially cau- tioned not to lie down on the ground. Asphyxia supervening on extreme fatigue has been frequently noticed in the French army in Algeria, par- ticularly during the occurrence of the sirocco. Even mania has followed protracted marching in the tropics; and in Bugeaud's expedition into Tunis in 1836 there were eleven suicides recorded in the French forces. Insolation. — No precaution should be neglected in the prevention of sunstroke, which is one of the most serious calamities liable to affect white troops during campaign in the tropics. Thus it is reported by Morehead that in India, in 1858, the Seventy-first regiment lost 89 men by death from insolation between the 5th of May and the 15th of August. The frequency of sunstroke among the British troops in India was very great when the soldier was required to carry the same weight and wear the same uniform as in England, but became much rarer when a special system in this respect was adopted for tropical service. In the expedition of Bu- geaud in Algeria, just mentioned, more than 200 men were reported as being sunstruck ; but during the campaign of the French army in Mexico insolation was rare, probably through the altitude of the region in which, military operations were conducted. The extinction of vitality by extreme heat is also common in temperate climates during the heated period ; being perhaps almost as frequent as in the tropics. This is probably due to the fact that, in hot climates, sunstroke is always apprehended and measures are accordingly taken to avoid it by modifications in the way of dress, weight of equipment, hours for marching, rapidity of marching and other conditions. In temperate climates, these precautions are rarely taken in summer and the soldier is thoughtlessly required to manoeuver under the heavy garments and burdens of a winter campaign. Viry states that, on July 8th, 1853, two-thirds of a Belgian regiment were struck down by heat whUe on the march ; and that during the last war in Italy, on a hot July day, no less than 2,000 men in one division of the French army fell out of the ranks from this cause. In 1878, the Aus- trian troops occupying Bosnia lost many men from sunstroke ; one regiment on the march having 320 cases with 31 deaths, while the total number of cases of insolation during the campaign amounted to 2,131. In July, 1879, a regiment of Italian bersaglieri left 200 men along Uie road, overcome by the heat, during a march of 35 kilometers. Sunstroke is said to be par- ticularly comrnqn in the German army, and it is stated that on May 21st, 1827, the troops maneuvering near Berlin were completely disorganized by heat, entire companies falling along the route and the cavalry losing many horses. In our own service, but little marching is done, during time of peace, until the heated season is past — but during the ten years 1888-1897 there were 523 cases of sunstroke. In the tropical islands, our troops have suffered considerably from sunstroke during the past two years. During THE HYGIENE OF HOT AND COLD CLIMATES. 905 the recent relief expedition in China the great heat resulted in much suf- fering ; during the march on Pekin there were 8 deaths in a regiment about 1,200 strong, and it is said that at one time about one-fourth of the com- mand was unfitted for marching from this cause. It appears to be excess of internal heat more than sunshine which, re- sults in the phenomena known as insolation ; and hence the condition may occur at night if the atmosphere, while hot, is also saturated with moist- ure, and heat dissipation, through evaporation of perspiration, is imperfectly carried on. Insolation rarely occurs at a high altitude and iu a dry cli- mate, no matter how elevated the temperature. Laveran and Eegnard have found that as soon as the bodily temperature exceeds 40° C. it begins to ex- ercise a marked influence upon the nervous system; this being greatly increased if the head is exposed to the direct solar rays. Wliere the condi- tion of insolation is actually established, the heat-regulating centers are dis- organized and the temperature is extraordinarily high. Death results from the primary stimulation and subsequent paralysis of the nervous system by the heat. Exercise is a great factor in the production of heat-stroke, and a large proportion of cases among marching troops depend almost as much on exhaustion as upon high temperature. Animals made to undergo violent exertion are more readily made to succumb than those allowed to rest quietly — and in the army it is the infantry which are most affected in this respect, cavalrymen being less liable to sunstroke than are their horses. Exercise greatly increases the production of body-heat, and Hiller found that the rectal temperature in soldiers after a hard march was that of a high fever. The mental strain and unconscious muscular rigidity which accompany mili- tary movements undoubtedly favor the occurrence of sunstroke. Anything which interferes with the loss of body -heat increases liability to sunstroke ; this including too heavy clothing, diminution of perspiration through de- ficient water-supply or lowering of the processes of evaporation through excessive humidity. If the atmosphere is both hot and moist, the loss of heat by the lungs is largely impaired; hence in a marching column, carrying with it a close atmosphere saturated with moisture, it is the men in the center of the ranks who are most liable to sunstroke. The period of digestion is favorable to insolation, and it is the debilitated or intem- perate who are most liable to suffer in this respect. Insolation is undoubt- edly aided by the pceaaure ef tight clothing, or the belts and straps by which the soldier's load is suspended from his person. McCartie, in India, records a striking instance in the Chitral campaign of 1897, when sufficient coolies could not be obtained and part of the baggage had to be carried by native soldiers. Before the end of the march, nearly all the men in the ranks were completely exhausted and some had heat apoplexy, while their com- rades, carrying a much heavier weight but having assumed the light and loose native dress, were not in the least distressed. The races indigenous to hot climates possess a notable immunity as re- gards sunstroke; this, in the negro, being especially great and furnishing an additional argument for the organization of native forces for tropical service. Some of the symptoms of insolation are said by iSTotter to be caused by the reflected rays of the sun through the orbit, when the optic nerve is exposed to direct rays of, light. In the British service, neutral- tinted glasses are frequently worn as a protection to the eyes, and the 906 THEORY AND PRACTICE OF MILITARY HYGIENE. sense of relief experienced by their wearers tells "the advantage their use affords. Such glasses in the form of goggles were found effective in the Egyptian campaign of 1882, as a protection against glare, heat and sand. With a better knowledge of the character of light, it has been suggested that the actinic rays may be a strong factor in the production of insolation. These can be arrested by a layer of color used as a filter. Dark red, yellow or green is such a color, and the material or thickness in which it is present is a matter of comparatively little importance. A lining of such a color has been recommended for the hfead-coyering and for the blouse directly over the spine. Recently, in view of the qualities and destructive effects of the Roentgen rays, it has been proposed, for the interception of the latter, also to line the head-gear with a thin layer of tinfoil. The advance to the condition of insolation is gradual, and its occurrence can be largely prevented by careful observance of proper administrative de- tail. The march should be so planned as to avoid exercising during the heat of the day ; while the length of the distance ordinarily traversed in tem- perate climates should be diminished — or else the rapidity of movement lessened. Troops should march with as open ranks as possible, better to allow the access of fresh air to each soldier. Halts should be frequent, and at points which are well shaded, elevated and airy. During such halts the men should not lie down, since in very hot weather, particularly if the ground be bare, the soil is heated to a higher degree of temperature than is the atmosphere. Soldiers must have plenty of water, and hence can- teens should be filled as often as possible en route. The water should be drunk in small quantities but may be taken at frequent intervals. If a sufficiency of water along the route is not assured, arrangements must be made for the carriage of a supply with the column. This matter is given careful consideration in foreign armies, all of whom have some contrivance for getting extra water into the field. Absence of proper provision of this sort has caused much unnecessary suffering in our own army, an instance of which can be found during the late expedition in China. The use of alcohol in any form, previous to beginning or during the progress of the march, should be interdicted. The clothing worn should be adapted to the climate, should be loose and the head and back of the neck must be well protected. The upper buttons of the blouse may be unfastened and the handkerchief worn under the hat to protect the neck. Troops should not march on an empty stomach, but a hearty meal should not be taken im- mediately before marching. During the march, company officers should watch their men carefully. If a soldier looks pale, weak and exhausted, he should be spoken to sharply, and if he does not respond clearly he should be told to fall out and rest or await wagon transportation. Where sunstroke has actually occurred, the man should be carried into the shade, his clothing loosened and his equip- ment removed. His head, neck and face should be bathed with water and the coolness from its evaporation favored by vigorous fanning. Where the patient is able to swallow he shoidd be given water in small quantities at short intervals, and should be allowed to rest quietly until the arrival of an ambulance and medical attendance. It should be remembered that many cases of sunstroke result in per- manent impaii'ment of the nervous system and in the establishment of THE HYGIENE OF HOT AND COLD CLIMATES. 907 future susceptibility to the action of the solar rays. For the military service, the maxim " once sunstruck, always sunstruck " may be accepted as correct. Excretd and Refuse. — ^Where a sewerage system has not been laid, there is probably no better method of disposiug of the excreta in the tropics, either in camp or barracks, than by the use of the Smith crematory, already described. Next in desirability comes the trough and odorless excavator system; followuig which the use of dry-earth closets may be employed. Where the latter is in operation, sheds for the storing of dry earth should be provided for use during the rainy season. The primitive system of privy pits can never be accepted by military hygiene, least of all under tropical conditions. Where cess-pits already exist in houses or barracks to be oc- cupied by troops, these should be thoroughly cleansed, limed, filled with fresh earth and sealed over with cement. Soil-contamination by urine should be guarded against, and night-tubs or other convenient facilities for its reception should be provided. The disposition of garbage and refuse should be scrupulously carried out in the manner already described. Where natives are employed to do work of a sanitary nature, they must be care- fully watched, since they are generally not thorough in their methods. Cleanliness. ^ — Bathing of the person is particularly necessary in the tropics, to maintain the proper function of the skin and remove perspiration. Ample shower-bath faciLLties should be provided, and each man should be required to bathe himself at least three times weekly. Discipline, how- ever, will not usually be required to make the United States soldier bathe in tropical climates, since the cool bath is grateful not only during intense and relaxing heat but serves as a stimulus to the appetite and a tonic to mind and body. Where a special reaction of the skin is desired, a few slices of fresh limes may be added to the sponge-bath. Bathing is best performed, in the tropics, shortly before the second meal of the day, and this can usu- ally be accomplished. Sea-bathing is excellent, but should not be carried out when the sun is high. The waters of many tropical streams contain various parasites and may perhaps serve as a means for the occurrence of mal- arial infection, but bathing in clear running streams is not objectionable. In the tropics, it is necessary for comfort and health that the under- garments be frequently changed and washed. Unfortunately the methods employed by the native laundresses for securing the cleanliness of clothing are extremely unsanitary, and the dirt is pounded out with clubs in the near- est water-course, however polluted it may be. The garments are then spread on the ground to dry and are kept sprinkled until bleached. This prac- tice is undoubtedly a factor of no mean importance in the prevalence of skin diseases; particularly with regard to the so-called "dhobie itch," which is so prevalent in the tropics. It is probable, also, that contagious diseases and insect parasites are largely disseminated through the unsanitary habits and surroundings of the native laundresses. Hence it is important, at all tropical stations, that steam or other laundries should be established for the benefit of troops, in which clothing may be properly boUed, washed in pure water and dried by steam or on lines and not on the ground. Such laundries should be under official control and should be frequently inspected. Habits. In the tropics, the mind as well as the body should be exer- cised. Intellectual stagnation is as much to be avoided as physical torpor, and nothing is so likely to prevent irregular habits and resulting disease 908 THEOEY AND PEACTICE OF MILITARY HYGIENE. as well-ordered mental employment. During one season of the year, the enforced restraint, the never-ending downpour of rain, the dull and leaden sky, the sad and depressing influence of dark and gloomy days are all com- bined against the soldier to create nostalgia, ennui and discontent. Con- ditions of this sort are particularly trying to men of active brain quality and nervous temperament, and such are not unlikely to resort to stimulants when weary, restless and fretted. Hence it is of special importance, in addition to the imposition of light duties, that suitable sheltered spaces be provided for the recreation of the men and that every means be taken to secure their amusement. It is much to be desired that soldiers on tropical service should find pleasant means of passing the time within the limits of their own command; for much communication with neighboring towns, with their ever-present incentives to vice, drunkenness and disorder, is to be avoided. Troops should be governed with a light but firm hand, and rigid discipline should be maintained. The number of native camp followers within the limits of military control, particularly females, should be reduced to the limits of strict necessity. The free use of alcoholics, always inadvisable, becomes a source of great danger in the tropics, particularly to young men and to the unacclimated. Hard drinking is notoriously a predisposing cause of liver disease in India, and its depressant effects are sooner manifested and much more marked in degree in a hot climate than in more temperate regions. This latter point is particularly well demonstrated by the medical statistics of the British army, stationed as it is at points all over the world, in the temperate zones and in the tropics ; since it may fairly be presumed that the' habits of the British soldier, with respect to the use of alcohoKcs, do not change to any special extent as he is moved from station to station. The rates for alco- holism and its results, at the various stations of the British army, are as follows : Place. England Scotland Ireland Canada South Africa Gibraltar Bermuda West Indies Mauritius Ceylon China Straits Settlements. . . . India TEAR 1897, Ratio per 1,000 Strength. Admissions to hospital. 1.7 1.9 1.4 3.7 A 8.9 11.3 15.6 14.5 4.5 6.4 3. 5.3 Deaths. 0.01 .04 .04 .74 .03 Constantly non- effective. 0.06 .05 .05 .07 .03 .37 .30 .33 1.83 .13 .34 .07 .33 DECADE 1887-96, Ratio per 1,000 Strength. Admissions to hospital. 3.3 2.8 2 8.3 3 5 9.1 7.8 30 4.8 3.2 6.2 7.4 Deaths. 0.04 "".03 03 03 08 15 08 07 Constantly non- effective. 0.08 .06 .06 .09 .08 .18 .29 .19 1.30 .17 .16 .27 .24 On averaging together the above figures, it is seen that for the five stations in the temperate zone — England, Scotland, Ireland, Canada and South Africa — the ratio of admissions for alcoholism in 1897, per 1,000 strength, was 1.8; the death-rate from alcoholism was. .018 and the con- stant ineffectiveness from the same cause was .052. For the stations in THE HYGIENE OF HOT AND COLD CLIMATES. 909 hot and tropical climates — Gibraltar, Bermuda, West Indies, Mauritius, Ceylon, China, India and Straits Settlements — the admission rate for alco- holism during the same year was 8.68 per 1,000, the death rate from the same cause was .09 and the constant non-efficiency was .445. For the decade 1887-96, the rates per 1,000 were: For cold climates 2.64, .016 and .072 ; for hot climates 7.93, .06 and .337. These results are extremely interesting, since they show that not only do four times as many British soldiers require treatment in the tropics for alcoholism as do in temperate climates, but also that the death rate from alcoholism is more than four times greater ia hot climates than in the temperate zone. FuU data as to the relative influence of alcohol in producing inefficiency among United States troops serving in the tropics and at home stations, under similar conditions, are not as yet available ; but the report of the surgeon-general of the United States army for 1899, which gives deaths alone, shows that during the period May, 1898, to June, 1899, inclusive, the death rate from alcoholism was .14 per 1,000 among troops serving in the United States and .296 for troops serving in Cuba, Porto Eico and the islands of the Pacific — or more than twice as high in the tropics as in temperate regions. If it be objected that soldiers actually drink less in the tropics, then the above figures for the troops of Great Britain and the United States should obviously be increased to correspond with the deficiency in the alcohol used ; if the soldier is said to drink more liquor in the tropics than in a cool cli- mate, the evil results of such excessive drinking are shown by the above figures. In either case, the claim advanced by some that the use of alcohol is desirable in the tropics is refuted beyond the possibility of discussion. Further instances showing the influence of alcohol in impairing military efficiency in hot climates have been given in the preceding chapter. Much as moderation in eating is desirable in the tropics, moderation in the use of alcohol is obviously even more necessary. If the use of alcoholic liquors is persisted in despite due warning, these should preferably be taken with food and the pernicious habit of constantly taking small quan- tities should be avoided. As to the character of the beverages used, there is little doubt but that good claret, taken with water, is the least harmful — ^the other light wines coming second. Beer, in the tropics, is distaseful to many and provocative of bilious disorders. Spirits, particularly those of native production, are above aU the most injurious, and the great dangers attending their use should be impressed upon the men. It is of interest to note that both wine and rum, in considerable quantities, are in- cluded in the rations of the French and Spanish soldiers serving in the tropics. In the British army, however, the soldier is now rarely allowed the ration of spirits, when on campaign in the tropics, to which he is entitled on field service in temperate climates. This deprivation was the result of earnest representations on the part of observing officers, both line and medical ; and the reports of the medical officers accompanying subse- quent expeditions have been uniformly enthusiastic in favor of the substi- tution of tea for alcoholics. There are probably times, however, as during extraordinary labor under malarious conditions, when a little alcohol may be taken with advantage. As regards sexual gratification by new arrivals, there should be a special word of warning. The habits of heat production, so necessary for protec- 910 THEOEY AND PRACTICE OF MILITARY HYGIENE. tive purposes in a temperate climate, appear to be retained by the organism through its preliminary period of acclimation, even though not needed in the tropics. The genital function appears to be increased, while the lassi- tude incident to the tropics prevents the accustomed amount of exercise and so discourages the dissipation of excessive physical energy by other means. The result is a greatly heightened and exaggerated nisus gen- erativus. Excesses in venery are especially trying to the unacclimated, yet the character of the lower-class women of the tropics is apt to be such that opportunities are not wanting for the gratification of passion. While always vexatious, the allied questions of venereal disease and pros- titution become, in the tropics, a problem manifestly difficult of solution. On the one hand are a large number of young men of largely undeveloped and unstable character, surrounded by constant temptations to venery and at the age when animal instincts are at their maximum. On the other hand, there is a large native population in which fornication is not re- garded as a moral offence but as almost a legitimate calling ; and in whom, at least with the class wOling to consort with the soldier, venereal disease is much more common than among the corresponding classes in temperate climates. " The hard fact remains that among a body of men, mostly very young and nearly all, by the conditions of the service, obliged to remain unmarried, removed from home ties and restraints into a country where climate and environment conduce to sexual indulgence, comparatively few are able to control the strongest passion in human nature — and with disas- trous results." This, while written with respect to the British troops in India, applies with almost equal force to the soldiers of other nations serv- ing within the tropics. General Precautions. — Chilling is not less dangerous than exposure to the direct solar rays. As the skin is constantly moist with perspiration, exposure to a cuiTcnt of air wiU rapidly induce great reduction of surface temperature, and this, while not necessarily dangerous, becomes so if the vital resistance be lowered from exhaustion or debility. If forced to remain quiet while bathed with perspiration, exposure to drafts should be avoided and, if possible, some additional clothing should be donned. In the ar- rangement of squad-rooms the beds should be so located that no air-currents can pass directly over the sleepers. For the furtherance of this purpose, screens and latticed blinds wiU come into requisition. Exposure to rain-storms should, when possible, be avoided. Parke states, with reference to his travels in equatorial Africa, that "every one who got a wetting either by rain or by submersion in a lake or river, or who was exposed to a chilly breeze after perspiration, developed fever as an immediate consequence. Beasts as well as men suffered. The inference is obvious." Wetting and chilling are also well recognized as predisposing causes of dysentery and intestinal disorders. Wet clothing should be promptly changed ; the body being bathed with tepid water and rubbed briskly with a towel before putting on dry garments. If a change of clothing is not available, the individual should keep active until dry ; and under no circumstances, where the opposite is possible, should damp gar- ments be slept in. If troops are unavoidably exposed to continued wet weather, the administration of prophylactic doses of quinine may be ad\T[s- able in malarious localities. THE HYGIENE OF HOT AND COLD CLIMATES. 911 In the tropics, great attention must be paid to the state of the bowels. Constipation is the usual effect of prolonged residence in a hot climate — because of the fact that insufficient exercise is usually taken and it is not al- ways easy to get suitable fresh vegetables and vary the diet, liecause of the prevalent malarial conditions by which the liver is rendered inactive in its functions, but chiefly through the attraction of systemic fluids to the sur- face and their loss by perspiration. On the other hand, chilling or indis- cretions in diet are usually followed by diarrhoea and intestinal disorders. In all extremely malarious countries, a small prophylactic dose of quinine — about five grains — should be administered daily, preferably just before the evening meal. The routine use of quinine in aU parts of the tropics, without special indications for its use, is, however, undesirable. It often happens that sickness is produced by very slight indiscretions. Young soldiers in the vigor of present health are apt to disregard proper precautions for its preservation, but they may rest assured that the impor- tance of the latter is not over-estimated and that any intemperance of habit, indiscretion in diet, or such apparently small things as a brief exposure of the head to a hot sun or the laying aside of underclothing during a stifling night may lay the foundation of serious mischief. On the other hand, nothing is worse for troops in unhealthful localities or in time of epidemic disease than a state of nervous expectancy or apprehension — a condition as unwholesome as it is unmanly. Change of Climate. — The advantages of change of air in the tropics have been established by long experience ; and special camps or stations, to which troops are moved during the unhealthy season, are used in the colonial services of France and England and were formerly employed by Spain. Altitude in the tropics reproduces to a less degree the advantages of cold climates, and hence it is frequently advisable periodically to abandon the coast and low plains for a sojourn in the mountains. In general, the height selected should be greater than fifteen hundred feet but need not exceed three thousand feet. For practical purposes, it may be considered that each thousand feet of altitude lowers the average temperature about four degrees, but this rule is subject to slight variations. While it not infrequently happens that individuals may live in the tropics for long periods apparently unaffected by the heat and climatic conditions, it is none the less true that troops recruited in temperate climates, as a whole, are ultimately debilitated by such conditions and and require transfer to cooler stations. The period at the end of which such change becomes necessary naturally varies according to the unhealth- fulness of the locality ; but under no circumstances should white troops be kept in the tropics for a period longer than four years. The French limit the tour of service in Annam and Tonquin to two years, this period is undoubtedly somewhat long for the more insalubrious re- gions. It is stated that the Belgian forces on the Congo and the British white troops on the west coast of Africa are rotated yearly. For our own service, experience has shown that troops are so debilitated by service in the Philippines that to require a period of service longer than two years is inadvisable. For those seriously affected with such tropical diseases as malaria and dysentery, repatriation affords by far the best prospect of re- covery. 912 THEORY AND PEACTICE OF MILITAEY HYGIENE. II. THE HYGIENE OP COLD CLIMATES. With proper precautions, intense cold is better supported by troops re- cruited in the temperate zone than is tropical heat. The low temperatures of the far north are healthful; this being largely due to the small number of pathogenic micro-organisms capable of maintaiaing an existence under such conditions. It has long been noted that travelers in the circumpolar regions are unusually free from infectious disease, and Nordenskjold is au- thority for the statement that Spitzbergen, in summer, is the most healthy spot on earth. Levia has recently made a number of bacteriological ex- amination* of air in Spitzbergen and King Charlesland, a minimum of 1,800 Kters of air being filtered for^ach examination. In only one in- stance were bacteria found, the sample of air in that case being taken above, the deck of a vessel — and as only three colonies developed in this instance, it is a question whether a particle of dust from the ship did not get into the gelatin. On the other hand, all samples of water, whether taken from the sea, from glaciers or obtained by melting snow or ice, were found to contain bacteria in small numbers. In samples taken from the surface of the sea. Levin found only one micro-organism for each 11 c.c. of water — a proportion of germ-life which is absolutely insignificant in view of the fact that the same amount of water taken from the Seine below Paris has been found to contain more than 2,000,000 bacteria. It is interesting to note that the same investigator found the intestinal contents of various Arctic animals and birds to be entirely free from micro-organisms ; thus demon- strating that the presence of bacteria is not indispensable to the processes of digestion. In the consideration of the direct effects produced by cold, it must be borne in mind that actual temperature is not the only factor to be taken into account ; dryness and stHlness of the air permitting a much lower tempera- ture to be borne without discomfort than when the air is damp or in motion, while even a moderate wind wiU render a low temperature unbearable. Not only does much depend upon the degree of cold, but also upon the duration of exposure and the medium or manner of application ; and to these condi- tions may be added the extent of surface exposed and the general health or physiological condition of the individual. The great degree of cold which inhabitants of temperate climates can bear without ill effects is well shown by the experience of Arctic voyagers, Parry noting a temperature of —55° F., Franklin of -58° F., and Back of -70° F., or 102° F. below the fi-eezing- point. Even within the limits of the United States, a degree of cold equal to that attained in the Arctic regions is often experienced during the bitter winters of the northwest; the lowest temperature ever recorded in the United States being noted at the now abandoned military post of Camp Poplar Eiver, in eastern Montana, when the thermometer was said to have registered — 64° F. In the central portion of Alaska, where a number of garrisons are at present maintained, aU the rigors of the Arctic prevail; the winter temperature approximating that of southern Greenland. From these THE HYGIENE OF HOT AND COLD CLIMATES. 913 latter facts, the special measures calculated to promote the welfare and efficiency of troops serving in very cold climates may be briefly considered. In cold climates, accordiag to Catat, the respiratory function is im- paired. Eeasoning from the conditions already shown to exist in the tropics as compared with temperate cKmates, the rapidity of respiration should be increased while the volume of respired air is diminished. Tm-- ner states that great cold reduces bodily temperature and diminishes the force and frequency of the heart beats ; Catat noting that the pulse of the adult Greenlander is often no higher than forty beats per minute. The appetite is greatly increased and visceral secretions are abundant, due to constriction of the superficial capillaries and the absence of sensible perspiration. The digestive and metabolic functions are proportionately active to the increased amount of food required. Cutaneous sensibility is much diminished, but the sensory organs appear to take on a condition of extreme acuteness. During winter there is a constant tendency to sleep, a condition of irritability alternating with apathy, and often melancholia, hallucinations and delirium. Payer-States that the men " acquire an un- certain gait, like that of a drvmken man." Moderate cold, and very severe cold when acting through no very great period, undoubtedly exercises a tonic and stimulating influence upon the organism; but intense cold, par- ticularly when prolonged, is markedly depressant. The temperament best suited to service in the far north is that known as the sanguine ; individuals of this character being endowed with a more \'igorous power of assimilation, active circulation, florid skin, moderate de- posits of fat, large and firm muscles and the capacity for brisk movements and prolonged exertion. A notable quality generally possessed by this class is a superior power of producing animal heat under low temperatures ; justly esteemed by Eoss as being of the first importance in those serving in high latitudes. This heat-producing power, however, is possessed in varying degree by different persons, even if of like vigorous organiza- tion ; a degree of extreme cold being merely invigorating to one, while it might produce painful or exhausting depression in another. Unfortunately there is no ready test to determine the existence of this desirable quality in recruits, yet it may be safely asserted that it is possessed by northern peoples — Norwegians, Danes, Swedes, Canadians, New Englanders and in- habitants of our northern states — in greater degree than by those from the south ; and by the white race better than those of darker skin. Natives of the tropics soon succumb under conditions depending upon the more rigorous climate of colder countries, and Baudin cites the example of an English regiment composed of West Indian blacks, which, in. 1817, was sent to garrison the comparatively mild station of Gibraltar, with the result that it was almost entirely destroyed by tuberculosis in fifteen months. In France, according to Laveran, similar conditions have been observed among the convicts at Brest, some of whom are negroes from the colonies ; disease, €!speciaUy tuberculosis, making frightful inroads among the latter class and four-fifths of them being said to die annually. Among the military forces of the United States, the negro troops appear to possess an extremely great susceptibility to the action of cold as compared with white soldiers. Thus for the decade 1879-88, the admission rates for frost-bite, per 1,000 strength, were 6.33 for whites and 27.46 for colored troops; 58 914 THEOEY AI^TD PRACTICE OP MILITARY HYGIENE. Fi8. 38Z.— Arctic Over- shoe. while for the year 1889, the rates were 3.32 for whites and 27.32 among the colored. This great difference between the two races, in respect to sus- ceptibility to cold, is even more significant when it is remembered that the negro regiments are chiefly recruited in the more northern states — ^since the fact that natives of warm countries are unable to resist great cold is too well recognized to require argu- ment. The negro troops themselves dislike service at cold stations, and it very frequently happens that where such soldiers are discharged by expiration of term of service from regiments stationed in Montana or Dakota, they refuse to re-enlist in their former organizations but proceed at their own expense, for that purpose, to colored regiments serving in the southern part of the country. It would thus appear to be advisable, as far as practicable, to recruit for northern service from comparatively cold climates and from white persons of the type and physical character above described. For cold climates, as for the tropics, troops should be mature and well developed. With regard to clothing, for service in the cold weather of the far north it is essential that the underwear, particularly that worn next the skin, be made of woolen ; and for such conditions the heaviest underclothing at pres- ent issued is insuflEicient. For troops serving in such climates, an even heavier grade should be furnished, and for this purpose nothing is superior to the loosely woven Jaeger underwear. During winter marches or expedi- tions, much warmth and comfort will be derived from the use of a wide flannel bandage encircling the abdomen. Too much care cannot be given to the protection of the feet, the parts usually first to suffer from frost-bite. One of the best arrange- ments for the avoidance of this accident consists in the use of heavy, soft, woolen stockings over which, together with the trousers, the so-called German socks, heavy and reaching to the knees, are drawn. The foot should then be encased in loose moccasins and Arctic overshoes put on over the whole. Shoes made throughout of heavy felt afford excellent protection against a high degree of cold and are both light and comfortable. They are, however, quite costly, and are not sufficiently durable to meet the needs of the military service where much marchiag is to be done. Further, they are totally unfit for service during thaws or when the snow is damp, since they readily absorb and retain moisture. During intense cold, the use of leather about the feet greatly favors frost-bite, and the foot-wear must be sufficiently loose so as not to interfere with circulation. The outer clothing should be made of heavy kersey or blanket-cloth and should be loose so as not to in- terfere with the circulation or muscular action. Many hunters and explor- ers use suits of buckskin or chamois over the imderwear, but these soon lose thek pliability. A thick woolen sweater would be a most comfortable i. — Canvas Overcoat, Blanket-lined. THE HYGIENE OF HOT AND COLD CLIMATES. 915 384.— TTniform Fur Cap. addition to the uniform in cold climates. Until recently, troops at the colder stations were supplied with overcoats of buffalo fur ; but the supply of these is now practically exhausted and canvas overcoats, lined with heavy blanketing, are issued ia their place. These are al- most as warm as the fur overcoats and are much lighter, more pliable and closely fitting. The c^- vas, however, becomes extremely cold to the touch during low temperatures, and to minimize this defect it is necessary that the collar and cuffs be well faced with woolen material. The present method of fas- tening this coat, with buttons and loops, is inferior to the use of light snap-hooks and riags, for ease in fastening and unfastening with benumbed fingers. For winter exploring or sledgiag expeditions within the Arctic circle, the outer garments should be of fur and fashioned according to the style of the Esquimaux. For the protec- tion of the head, two kinds of head-gear are supplied. A cap of muskrat- fur is much liked by the troops and affords sufficient warmth and protection for ordinary conditions. It lacks, however, a chin-piece, and does not sufficiently protect the lower part of the face when marching against head-winds. A canvas cap, lined with flannel and hav- ing a chin and neck protector, is also issued at the colder stations. If made out of muskrat fur, it could scarcely be improved upon for military use where exposure to intense cold is required. Arctic explorers find the use of some protection for the nose to be essential, and for this purpose the face-cloth or nose-cover is much used. The muskrat fur gauntlets lined with flannel, furnished for use in cold climates, are warm, comfortable and deservedly popular among troops. A canvas mitten lined with heavy flannel is also authorized, but has not been issued to any great extent. Mittens are much warmer than gloves, and for expeditions in very cold climates the use of mittens, made of fur, is preferable. For military use, the method employed by the Eussians to prevent the loss of the hand-coverings — each being fastened to the end of a tape passed through the coat-sleeves — is advisable. With the clothing just described, troops will be well protected imder almost any conditions of temperature. Its provision is a mat- ter of comparatively recent accomplishment, and Wood- hull states that prior to its issue as much as fifteen per cent, of the troops at some of the stations in the north- west were incapacitated for duty, during severe weather, as a result of frost-bite. Next to the clothing, the sanitary precautions above all others in" importance, for those sojourning in high latitudes, relate to the food supply. Deficiency in quahty and quantity of food is sure to impair the strength of the men, favor the action of cold and invite disease; especially when conjoined with deficient sunlight, dampness, impra-e air, low temperature, defective cleanliness and want of Fig. It-N"t. ('.m\ i*^ Cap, ls,.irikL'i-lm«_ti. FIG. 386.— Fur Gaunt- let. 916 THEORY AND PRACTICE OF MILITARY HYGIENE. exercise. As to quantity, Franklin, speaking of food and clothing as sup- plementing each otlier during polar cold, says : " During the whole of our march we experienced that no quantity of clothing could keep us warm while we fasted, but on those occasions when we were able to go to bed with full stomachs we passed the night in a warm and comfortable manner." And Eoss wrote : " He ^ho is well fed resists cold better than the man who is stuited, while starvation from cold follows but too soon on starvation in food. In every expedition or voyage to a polar region the quantity of food should be increased, be that as inconvenient as it may. It would be desirable that men could acquire the taste of Greenland food, while all ex- perience has shown that the large use of oQ and fat meats is the true secret of life in these frozen regions." According to Dalton, the amount of food necessary for a man in full health and exercising in the open air, for the temperate zone, equals about 2.41 pounds of solids and 3.38 pounds of Kquids — or about one-twenty-fifth of the body-weight. These amounts, however, have been shown by experi- ence to be quite insufficient in Arctic climates — where the loss of heat is great and oxidation goes on rapidly — and fall far short of the ordinary diet of the native, which may undoubtedly be taken as a criterion, to a considerable extent, of the needs of the system under conditions of extreme cold. Ross states that an Esquimaux frequently eats as much as 20 pounds of flesh and oil daily. Parry's test of the appetite of an Esquimaux for a single meal was 8.5 pounds of meat and 1.75 pounds of bread, water not being counted, and the quantity was not considered extraordinary. In another instance, he gave to a young Esquimaux 10.25 pounds of solids, 9 pints of water, 1.25 pints of soup, 3.5 glasses of raw spirits and a tumblerful of strong grog. In yet another instance, the subject ate of solids at a single sitting : Lbs. Oz. Bread dust and train oil 1 10 Walrus flesh, boiled 7 1 Seal and bread 1 Two tallow candles 3 Bread and butter 1 Total 9 15 At the same meal the subject drank two quarts of rich walrus soup and four quarts of water. Simpson states that a Yakut ate 9 pounds of beef and 4.5 pounds of butter within an hour ; and Hayes says : " I have frequently seen an Esquimaux eat from 6 to 12 pounds of meat, one-third of which was fat, and I should place the daily consumption of the men at from 12 to 15 pounds." Kane wrote : "I should average the Esquimaux ration at 8 or 10 pounds a day, with soup to the extent of half a gallon." Such quantities of food are not considered by the authorities quoted as representing the extremes ; and using these observations in connection with the fact that the amount of food ordinarily sufficient in the temperate zone is quite inade- quate to support the system and supply the necessary heat in the Arctic, and that the explorer instinctively approximates his diet in both character and quantity to that of the native, it is safe to say that the daily incre- ment of food for very cold climates should be equal to one-twentieth of the body weight — varied according to the isothermal lines — and that half the material so taken should be dry solids. THE HYGIENE OF HOT AND COLD CLIMATES. 917 In character, the best foods for cold climates are those concentrated forms which are readily and easily transformed into heat, and these are the kinds which are provided by nature in the abundant animal life to be found along the Arctic littoral. Fats are especially craved and are taken in large quantities, the northern explorer promptly adopting the practice of the native in this respect. Kane says : " Our journeys have taught us the wisdom of the Esquimaux appetite and there are few among us who do not relish a slice of raw blubber or a chunk of frozen walrus beef. The liver of a walrus, eaten with little slices of his fat, of a verity is a delicious morsel." Fresh meat should be used wherever obtainable and needs no special means of preservation so long as the temperature remains below the freez- ing-point. Where scurvy is to be dreaded, the meat should be eaten under- done ; and Kane recommends the use of raw flesh for this purpose, which, when frozen, he states is not at all distasteful to the civiLked palate. No opportunity for securiag fresh animal food should be lost by scouting or sledging parties, for the use of preserved meats in excess, except pemmi- can, is injurious and promotive of mal-nutrition and scurvy. From what has been said, it would appear that the present ration of our service is insufficient and improperly constituted for the use of troops serving at stations near or within the Arctic Circle. While sufficient data are not available to permit of accurate calculations on this point, it is un- doubtedly true that an increase of at least one-half in the meat components of the ration — particularly bacon or pork — would be of great advantage, and that, under conditions where great hardship and cold are to be under- gone, this amount should be still further augmented. With the fats and proteid, a certain proportion of carbohydrates should be,suppKed, especially in the form of bread and dried or preserved fruits. Vegetables are essential, either dried, fresh or cann'ed. In their absence, the natives of northern climates supplement their meat diet whenever pos- sible by the use of angelica, dandelion, sorrel and bilbeiTies ; also by the contents of the stomachs of the rerodeer, caribou, moose and musk-ox, these consisting of fine mosses and grasses in a partially digested condition. Fresh potatoes can be preserved any length of time for use under such conditions of climate by being , covered with black molasses after being cleaned, pared and cut into small cubes. After washing, the taste and texture of the tuber remain. On board whaling and exploring ships, it is customary to germinate large quantities of seeds by the heat of the stoves and use the sprouts thus produced as vegetables. This could readily be done by troops stationed in the interior of Alaska and would often be of service. Where an abundance of fresh meat and vegetables is not avail- able, the daily issue of an ounce of lime-juice is advisable for the preven- tion of scurvy. Acid wines and home-made beers are also valuable for this purpose, but spirituous liquors diminish the power of resistance to cold and their use is obviously dangerous. Tea is the favorite beverage in cold climates and is drunk hot in large quantities. The eating of snow to quench thirst should be avoided. While sledging expeditions in the Arctic have been exposed, without suffering, to continuous cold of as great a degree as —50° F., soldiers, on the other hand, have often been known to succumb to cold in comparatively warm climates and at a time when the thermometer registered by no means 918 THEOEY AND PEACTICE OE MILITAEY HYGIENE. a very low temperature. It may fairly be considered that accidents from this cause are relatively more frequent in the cold weather of temperate climates than iu that of the far north, probably because of the greater precautions taken for the conservation of the body -heat under the latter conditions. Siace the famous retreat of the Ten Thousand when a rigorous climate destroyed more Greek soldiers than did the Persians, great cold has fre- quently exerted a strong influence upon military operations. Voltaire states that in the winter of 1709 a large part of the army of Charles XII. was destroyed by cold, 2,000 men being frozen to death during one march. In 1719, 7,000 Swedes, on their way to the siege of Dron- theim, perished in the mountains between Sweden and Norway; while in 1742, in the retreat from Prague, 4,000 French . soldiers died from cold and want. The sufferings of our own troops at Valley Forge are a matter of history ; and in the destruction of Napoleon's army in Eus- sia, cold was by far the greatest factor. During the Crimean War, ac- cording to Viry, there were 5,290 cases of frost-bite with 1,179 deaths among the FrencBi troops ; while among the English forces there were 2,852 congelations with 463 deaths. Laveran states that during the winter of 1870-71, freezing of the feet caused much suffering in the French army and there were many deaths from cold. In 1879, according to the same authority, a column of 755 men in the mountains of Algeria, at the end of the month of March, had 60 cases of frost-bite, of which 19 proved fatal. In our own service, for the decade 1888-97, the influence of cold on a constant strength of about 24,000 men was as follows: Year. Cases. Deaths. Discharges. Year. Cases. Deaths. Discharges. 1888 1889 1890 1891 1893 141 34 60 62 66 67 5 3 1 'i 1 1894 1895 1896 1897 Total .... 58 54 47 59 .... 1 '3 1893 648 13 It should be remembered, however, that of the United States forces hut a small part was stationed in regions where frost-bite was liable to occur, and hence the cases reported necessarily related to a comparatively small fraction of the whole army. The history of congelation in armies shows that a state of low vital re- sistance, brought about by tmfavorable hygienic conditions, plays almost as important a r6le as that of cold itself, and it is a matter of common obser- vation that accidents from freezing occur far more frequently among such soldiers as are weakened by fatigue, sickness and privation. During the Crimean War, the temperature was never very low, and a report of the time suggests that the large number of congelations observed among the soldiers might justly be regarded as " gangrene owing to scorbutic tendency exaggerated by cold." On the other hand, troops which are well fed and warmly clad resist the most intense cold without injury, as has been re- peatedly shown in our winter campaigns against the Indians of the north- west. In the Powder Eiver expedition of 1876, conducted during the three winter months, and with the mercury never above freezing and often down THE HYGIENE OF HOT AND COLD CLIMATES. 919 to —40° r., Eosse states that in a force of about 2,000 men but 31 cases of frost-bite were reported, while no cases were reported among the 350 In- dians with the command. During the winter of 1891-92, when about 6,000 troops were constantly in the field against hostile Sioux, only 62 cases of congelation occurred. The phenomena which precede the death of the soldier from cold, while on the march, are well described by Larrey : " The dangerous condition is shown in the pallor of the face, by a kind of idiocy, by difficulty in speak- ing, by feebleness of vision or perhaps total loss of that sense, and in that state they march for a greater or less length of time, conducted by their comrades or friends ; the muscular action is weak and the individual totters on his legs like a drunken man. This weakness is progressive and is a certain sign of the extinction of life. Separated from the column and abandoned to themselves, they soon lost their balance, fell into ditches cov- ered with snow, a state of lethargy ensued and a few moments terminated their miserable existence." There is sometimes muscular contraction during freezing, particularly of the neck mus- cles, together with symptoms like those of catalepsy. Ac- cording to Forestius, soldiers have been found frozen and standing with arms in their hands — and the same thiug was observed by Larrey dming the retreat from Moscow. In the prevention of con- gelation, an abundance of nu- tritious food is only second in importance to sufficient and proper clothing. The extremities are usually the main points of attack, owiag to their relatively poor protection and distance from the main sources of systemic heat. The feet are particularly susceptible to frost-bite, a fact showing the necessity of warm protection and water-tight, loose and comfortable foot-wear. To protect the hands, heavy gloves or- mittens are essential, the latter being preferable. It is of advantage in dimiaishing the effects of cold upon exposed smfaces, such as the face, particularly in the case of driving snow-^orms, thoroughly to anoint the parts with some greasy substance, as the fat of beef, pork or mutton, or vaseline. Whenever possible, hot food or drink should be served out to troops on the march ; and this may be accomplished without the delay incident to buildiug fires by the use of the so-called Norwegian stove — an apparatus readily improvised from an ordinary camp-kettle fitted into a thick felt covering. With this arrangement, the soup or stew is raised to the boiliiig-point, removed from the fire, the kettle inserted into the felt sheath and the whole carried with the column. The process of stewing contiaues automatically, and even after several hours' marching in the cold the temperature of the soup does not fall below 100° F. This method has been used with much success with moving commands in the Eussian and Austrian services. If a march must be made in ex- FiG. 387.— Norwegian Stove. 920 THEORY A^B PRACTICE OF MILITARY HYGIENE. tremely cold weather, it should be concluded as soon as possible with- out undue fatigue; the ranks being well closed up and no one allowed to leave the column. In general, however, if an army is well fed, well clothed and free from sickness, it can imdertake a winter campaign with perfect safety if the distances to be marched are not too long. Where frost-bite has actually occurred, the treatment consists in the prompt fric- tion of the affected part with snow or brisk rubbing when immersed in ice and water. Only after reaction is fairly established, shguld the sufferer be allowed to enter a warm room or approach a fire. The glare of bright sunlight upon fields of snow produces the condition known as snow-blindness, particularly when troops are subject to prolonged marching toward the end of winter or in the early spring of the high lati- tudes. Since, in our service, soldiers are ordinarily housed in barracks dur- ing cold weather, the admission rate for this cause is usually low — only three or four cases per annum — but in the winter of 1890-91 there were 133 admissions to sick report from this cause; chiefly among the 6,000 troops engaged in that year in the campaign against the Sioux of the northwest. In the month of March, 1894, of a company about fifty strong, marching a distance of about sixty miles during a period of three days, nearly all were incapacitated for duty by reason of snow-blindness. This condition may be usually prevented among soldiers by smearing the eyelids and upper part of the cheeks with a mixture of charcoal and grease ; but where exposure to the glare is constant, as in the sledging parties of the far north, further protection is necessary. Por this purpose, dark goggles, fitted in frames covered with chamois skin, have been recommended. The " snow- eyes " of the Esquimaux are made of light wood with a bridge resting on the nose, lik^" spectacles, and presenting narrow transverse slits for the passage of light. These are said to be superior to goggles as a protection against glare, and are not liable to the accident of fracture. Under any circumstances, if snow-blindness is to be apprehended, the men should be imarched in close column and each soldier directed to keep his eyes upon the dark clothing of the man in front of him — the leading rank being fre- quently changed to the rear. Guard duty is particularly dangerous diu-ing cold weather, and sentinels should be kept on post not more than an hour at a time ; or a running guard may be established. "When relieved from sentry-duty, the soldier should not be permitted to lie down at once but should be required to pace briskly around the fires until numbness has worn off. Under stress of severe weather, men should be told off to keep up the fires. If forced to bivouac on snow-covered gi-ound, the piliag up of snow around the men will afford great protection from cold winds, and, with a fire in the center of each cleared space, properly clothed troops, except in the severest weather, will sleep without much danger of freezing and often not uncomfortably. In the absence of other shelter, during very low tem- peratures, excellent temporary protection against the cold may be made from large blocks of snow cut from well-packed drifts — or the drifts them- selves may be burrowed into by the men. Where canvas shelters are used in cold climates, the wall tent will be found superior to the conical tent on account of the height of the latter and consequent greater difficulty in heating. The tent for service of this THE HYGIENE OE HOT AND COLD CLIMATES. 921 character should be made of double thicknesses of canvas, sewed together at the edges and quilted at suitable intervals to divide the intervening air-space into small sections and thus prevent the establishment of too great movement of air in this insulating space. The sod-cloth should be made in two flaps ; one being turned inside the tent as at present, while the other flap extends around the outside of the tent and is heaped with snow to serve as a wind- break and partialis take the place of tent pins, always difficult to drive in frozen ground. Small apertures at the junction of the outer sod-cloth and wall are left to allow of the driving of such pins as may be necessary. The end of this tent, instead of being slit down the center to form the door, should be formed of overlapping canvas, giving a " double-breasted " effect, extending completely over one-half of the end and two-thirds of the dis- tance to the wall on the other side ; the ends of this canvas being provided with grommets and rings for fastening. The doorway of this tent is thus brought to the outer third of each half of the end, the aperture varying from one to the other side according as one or the other canvas-flap is drawn externally. The outer flap is now pegged at its end to a distance of several feet away from the tent. The windward flap is always made the external one, and in this way a sheltered valvular doorway, perfectly pro- tected against wind or snow, is provided. Should the wind change to the opposite direction, the flaps are readily reversed. If additional tent-space is desired, both flaps can be brought together, buttoned at the edges and stretched tightly by a peg and guy rope at the comers; the capacity of the wall tent being increased nearly one-half by this method. This pat- tern of tent was proposed by the writer during the winter of 1899— 1900. Its advantages as to warmth and shelter, as compared with the present tent, are obvious. For more permanent habitations, heavy log- houses, well chinked, wiU be found comfortable; or tight frame struc- tures made with double or triple walls and enclosing dead-air spaces, built on the principle of the cold-storage buildings already described, wiU be in every way satisfactory. The doors and window-spaces should not be too large, and for very cold climates the latter should be provided with triple sashes. The action of great cold has a direct effect upon ventilation by causing troops tightly to seal up their quarters ; the foul air thus engen- dered undoubtedly playing an important part in the genesis of scurvy as well as other diseases. Hence every care should be given to the provision of a suitable means of ventilation ; but this is a difficult matter and one to be accomplished only with the loss of a considerable amount of heat. It may be here remarked, however, that it is neither necessary nor desirable to raise the temperature of habitations too high in climates of this character. One not exceeding 55° F. is perfectly compatible with health and comfort and at the same time the inconvenient condensation of body moisture, produced in greater quantity at higher temperatures, is largely avoided. This con- densation of moisture is a matter of such importance under these conditions that it is reported of the Arctic voyage of the exploring ship Alert that the covered spaces under the bxmks became filled with ice from the body-moist- ure of the occupants before the condition was discovered ; while the amount of frozen moisture removed from the well, through which air made its escape from the cabin of the ship, amounted to as much as a bushel in the twenty- four hours. 922 THEORY AND PRACTICE OF MILITARY HYGIENE. For bedding in the field, ia the far north, nothiag is better than the sleepiag-bag. This is usually of canvas, lined with one or more thick- nesses of felt or furs, and is not only warm in any weather but wiud and moisture-proof. While the use of sleeping-bags is probably not prac- ticable in the case of large bodies of men, they should always be provided for small expeditions. Weight for weight, they afford much better pro- tection than do blankets. Where regular sleeping-bags are not available, substitutes may be extemporised from blankets by the method described in a previous chapter. The disposal of excreta and refuse is a simple matter in cold climates, since odor and putrefactive processes are promptly destroyed, and when cleansing is necessary the frozen mass is readily removed. Latrines should be sufficiently warm to prevent undue exposure of the person to extremely low temperatures when obeying the calls of nature. In Arctic expedi- tions, the warm snow-hut or tent, occupied during the previous night for sleeping purposes, is ordinarily used in the morning as a latrine before the abandonment of the camp site on resuming the march. CHAPTER XIX. THE HYGIENE OF THE TEOOP-SHIP. The transport service of the United States army is not the result of long experience and careful forethought, but has been a sudden creation due to immediate necessity. As a consequence, no vessel has been built for the special purpose of transporting troops; but such steam-ships as could be acquired by the Government through emergency purchase, during and subsequent to the war with Spain, were more or less hastily remod- eled to suit varying, and supposedly temporary, conditions. The trans- port Thomas, accommodatiDg 1,653 men, may be regarded as a fair type of the larger and better class of troop-ships ; but in general these vessels are so dissimilar in tonnage, build and equipment that any attempt at their de- scription as a class is manifestly impossible. StiU, there are many general conditions affecting the health of troops on board ship, irrespective of the special structural details of the latter, and these it is the purpose of the present chapter briefly to discuss. Perhaps the most important sanitary problem on board ship is to get fresh air in, while keeping water out. The simplest devices for the accom- plishment of the former end are wind-sails and cowls, in which use is made of the natural movements of air. These, whQe valuable, give only imperfect results, and hence should be looked upon merely as accessories to more precise means of ventilation. They have the defect of delivering the most air when least needed, require considerable attention, often allow the en- trance of water dm-ing wet weather, and, by the cold drafts which they may cause, are frequently looked upon as sources of annoyance by those whom they are intended to benefit. For this reason, whenever used, they should be frequently inspected to see that they are in working order and are not plugged or tied up by the men. These forms of apparatus will now be rarely required for the ventilation of troop-quarters except in emergency, and find their chief field of usefulness, on transports, in renewing the air of holds and other dead spaces not used for living purposes. Air-ports assist materially in securing ventilation, but cannot always be kept open on ac- count of rough and stormy weather. They should be provided with pivoted side-lights, by which the air can be forced in or directed out- ward while the vessel is in motion. They should invariably be kept open except when this is attended with actual risk, and their control, in quarters, should be delegated to non-commissioned officers. Hatch-ways, also, shoidd be kept open durrog fair weather, but should be screened with gratings for protection against accident. In some ships used for commer- cial purposes, ventilation is carried on by passing the air from the hold and bilge through the furnace and thus producing an aspiratory effect. In cer- tain British troop-ships, ventilation is secured by an upward draft created 924 THEORY AND PRACTICE OP MILITARY HYGIENE. by steam- jets, as already mentioned, but this system is objectionable on ac- comit of the noise, the waste of steam and the condensation of water in the air-shaft. The rotary-fan system is the most efficient and practicable method of accomplishing ventilation on board ship. In this system, the fan revolves ia a metal tube, haviug numerous branches ; air being aspirated from the outside and driven through suitable flues to the various parts of the vessel, while a reversal of the fan converts the inlet into a discharge -pipe. With aspiration of the confined air, a fresh supply finds its way into the ship through wind-sails, ventUating-shafts, hatch-ways and ports, entering the apartments by doors, crevices or other natural openings. It is of course necessary that such fans should have fresh-air connections and not merely put ,in motion air already in the compartment. The system of ventilation used on our transports consists in forcing in fresh air, but this is imdoubt- edly inferior to a simultaneous use of the supply and exhaust systems. By either method alone, there is a strong tendency to draw in or expel air through the hatch-way or ventilating opening nearest the fans without renewing the atmosphere in the more distant parts of the ship. The fact should not be overlooked, in the ventilation of ships, that the diffusive power of air is small when compared with its tendency to move along the line of least resistance. The amount of air going in and that going out of a space is by no means indicative of the thoroughness of the general circulation. Each important compartment should have its own ventilating system, for the movement of air is much impeded by bends in the distributing channels. As with barracks, care should be taken that inlet shafts are short and are changed in direction at such an angle as to present the least resistance through friction. The ventilating fans should, of course, be cal- culated as to number, power and size, according to the amount of fresh air which the maximum number of occupants will require. The outlets and their exhausts should be adapted to the inlets and the supply of air which they admit, and both should be proportioned to the numlDcr of persons destroying the air of the apartment to be ventilated. Among other desid- erata in all mechanical appliances for this object, they should be automatic, and should also work without noise and without creating perceptible drafts. Their use should necessitate no long shafts or chimneys, which, if carried away by a wave or the wind, would leave openings by which the sea might gain entrance. To avoid drafts, aU outlets into quarters should be covered with fine wire-gauze and should present an open space twice the area of the air-shaft. Effective ventilation demands that every possible obstruction to the circulation and diffusion of air be removed, and hence chests, lockers, racks and other bulky articles should not be allowed in quarters. The thwart-ship bulkheads should be as few as possible, and under all circum- stances should be perforated, latticed or louvi-ed at top and bottom. On this account, it would be of advantage if a single compartment, running the whole length of the vessel, could be provided for the quarters of the men. Passages about the ship should be as straight as possible to avoid impeding the movement of air ; which must be able to move freely fore and aft. and also from side to side, else the ventilation of the lee side of the THE HYGIENE OF THE TROOP-SHIP. 925 ■a I 926 THEOEY AND PEACTICE OF MILITAEY HYGIENE. I THE HYGIENE OF THE TEOOP-SHIP. 927 vessel will suffer. Stores, baggage and articles composing the cargo, should be so disposed as to leave passage-ways around and between them. Pan- tries and store-rooms are too often located without regard to convenience, ventilation, cleanliness and light. Such rooms, together with the galleys, are almost always a source of disagreeable odors and should be specially ventilated by the exhaust system. To allow proper cubic space to each soldier is usually impossible on board ship. In the merchant marine, the average air-space available per man is rarely more than 125 cubic feet and frequently may be as low as 60; the British maritime laws prescribing 72 cubic feet as a minimum. Every effort should be made, however, to allow at least 200 cubic feet per capita. With this space, supplemented by efficient ventilation and careful police, it is probable that no serious trouble may be apprehended as a result of over-crowding during an ordinary voyage. When a troop-ship is at anchor, especially in hot cKmates, a spring should be put on the cable so that the broad side of the vessel, with its numerous portholes and other apertures, may be turned to the wind and thus permit of ventilation by perflation. In the British service, on some stations, this procedure is officially prescribed for ships of war. The anchor- age in malarial ports, or those in which disease is epidemic, should be made to windward and at least one mile distant from possible sources of infection. The vicinity of marshes, sewers, festering mud-flats and the mouths of foul tidal rivers, discharging the debris resulting from human occupation along their banks, should be avoided. The problem of heating, so difficult of solution on sailing vessels, is readily settled on steam-ships by the use of steam-coils. The system should be so planned that a certain portion can be shut off without inter- fering with another part or with the whole. To reduce the heating of the ship by the solar rays while in tropical waters, the coloring- of the external surface should be white or light yeUow. Lighting is, of course, best accomplished by the use of incandescent electric bulbs, these giving ample light without danger of conflagration, the production of any great amount of heat or vitiation of an already confined atmosphere. The universal experience of medical officers is that a damp ship is an unhealthy ship. Dryness is essential — Tryon stating that of two ships cruising together, the sick-rate of the one with the most water between decks is invariably the higher. Nothing is more undesirable than too frequent and indiscreet use of water on the decks, especially those upon which troops must sleep ; yet this is the usual routine practice resulting from mistaken ideas of cleanliness. Sea-air normally contains a large pro- portion of moisture which on board ship is unavoidably increased by bodily exhalations — hence any further and unnecessary increase of humid- ity by artfficial means should be avoided. All decks should be coated with ' shellac or with linoleum, cemented in place to prevent absorption of moisture. The lower decks should never be wetted except for a brief cleaning, and then only on very dry days and not oftener than once a week. Even open-air decks should be washed only on sunny days and never except when really necessary. The minimum amount of water should always be used for this purpose ; its lavish use in cleaning decks generally implying an iaefficient police. Where unclean work must be 928 THEORY AND PEACTICE OF MILITARY HYGIENE. performed, a subsequent washing may usually be rendered unnecessary by sanding the decks or by the use of tarpaulins. In the British transport service, it is recommended that the decks be sprinkled with clean sand and sawdust when troops put to sea, to receive the discharges from sea-sickness. This is removed on the following day and more laid down; the process being repeated until the men have become habituated to the motion of the ship. The troop-decks can be readily kept clean subsequently by sprink- ling with hot sand, holystoning and dry rubbing. It is officially prescribed that wet swabbing should be employed only when required by local patches of filth. All movable articles which require washing should be wetted and dried only in the open air. The change from wood to iron, in the construction of ships, has in- creased the disadvantages due to the condensation of atmospheric moisture, with resulting dampness. This fault may be overcome in part by lining the ship with wood; but this material soon becomes dirty and ill-smell- ing and harbors vermin. Cork-paint, an excellent non-conductor, is now much used as a coating for aU metal work, and greatly diminishes conden- sation. Not only the walls but the ceilings should be overlaid with this material. It should be put on firm, smooth sheets ; since when rough it is a constant source of minor injuries through the roll of the ship, and is also retentive of dust. Particularly is it of importance that the hold be kept dry. One great cause of dampness on board ship consists in taking on supplies in wet weather, and, unless absolutely imperative, the coal and cargo should be loaded only on fair days. Before being placed in the hold, all barrels apt to leak should be whitewashed, as a ready means of discovering leakage should it subsequently occur. An efficient system of ventilation is of great value in drying the ship and diminishing humidity. All drainage naturally tends through gi-avitation to the bilge or lowest part of the ship, where it forms the highly offensive liquid known as bUge-water. This fiuid is a mixture of sea-water which finds entrance through defects in the hull or is deliberately admitted for purposes of cleanliness, of coal-dust and ashes, of oil from the machinery, of fresh water spilled from the tanks and of oozings from barrels of wet provisions. Dissolved in this Kquid is a considerable amount of organic debris, which, on decomposing, emits foul odors. The exhalations from the bilge are thus much more offensive and dangerous than the ground-air of a house — to which it is compared by Blyth. It is, in fact, more like sewer-air. The perpetual motion of the ship, although of assistance for purposes of ventilation, only tends to in- crease the evolution of gases from below by the constant agitation of the bilge-water. To avoid this production of gases, the bilge-space should drain into depressions which can be readily evacuated by pumping. Mac- donald recommends that the bilge-floors on either side of the keelson should be made perfectly smooth, and be cemented, lacquered or tiled, with suffi- cient incline from both ends of the vessel to the well. The liquid which gravitates to these points should be frequently removed and replaced by fresh sea-water. After the lapse of about an hour, this in turn should be discharged, and the proceeding repeated until the fluid brought up is en- tirely free from odor. On concluding the operation, the bilge should be pumped entirely dry. Great care in keeping the ship dry and clean wiU THE HYGIENE OF THE TEOOP-SHIP. 929 minimize the production and offensiveness of bilge-water. The use of anti- septics and deodorants, notwithstanding their efficacy in preventing foul smells and the evolution of noxious gases, should never be relied on to the exclusion of the frequent and complete removal overboard of the bilge- water itself. The best location of quarters for troops is where the motion is least, which is abaft the midship section of the vessel ; and there should never be more than two decks, preferably only one, occupied by the berths of soldiers. As to floor-space, twenty square feet per capita should be al- lowed as a minimum, and not more than two tiers of hammocks or bunks should be permitted. Where bunks are used, the lower tier 'should be raised not less than eighteen inches above the deck ; with not less than three feet between the two tiers, and between the upper tier and the ceiling, so as to enable the occupants to sit upright. All bunks should be arranged so as to leavea passage-way at least thirty inches wide between each other and the side of the ship, to facilitate cleansing, allow ready communication and ventilation and prevent chilling from condensed moisture or cold. The bunks themselves should have a frame-work of light iron tubing, painted white or light gray, which should be readily removable and supported on stout iron stanchions. In dimensions, the bunks should not be less than six feet three inches by two feet. Woven-wire mattresses are liable to rust, and are unfitted for use on upper bunks since they allow dirt and dust to fall through on to the bunk below. Canvas strips, stretched between the bed-frames, are cleanly, comfortable, occupy little space and are readily removed and handled. These should be washed after every trip — and more frequently if necessary. Shuck or straw mattresses are totally unsuited for use on board transports and soon become soiled and offensive. Vermin, if found to be present, should be relentlessly pursued. A high standard of cleanliness should be enforced, since on steam-vessels the facilities available for maintaining cleanliness are exceptionally great and no reason- able excuse can be offered for an inefficient police. All bunks should be made up neatly at reveille, rolling back the upper blanket to expose the interior, after which the troops should be sent on deck. The men should not be allowed to sleep on deck after sunset, from the danger of chiUing. On board ship, on account of the necessarily confined quarters, personal cleanliness is of the utmost importance, and the men should be required to bathe the entire person daily. For this purpose the shower-bath, as now provided on most transports, is unequalled. In its absence, a place on the spar-deck should be set aside, where the men can strip behind canvas screens and be doused with salt water from the deck-hose. Swimming, when practicable, is to be encouraged under proper precautions. Special soap, suited for use with salt water, should be issued gratis to troops on embark- ation. Abundant lavatory facilities should be provided. All clothiag should be kept clean and dry. For this purpose, each troop-ship should be provided with a steam-laundry and drying-room of sufficient size. Where such facilities are not furnished, two days a week should be set aside in which the men should be required to wash thek own clothiag by such less convenient means as may be available. When the weather permits, blankets should be exposed to the sun and air at least once weekly. On the conclusion of each trip, aU bedding — as mattresses, pillows 59 930 THEORY AND PRACTICE OF MILITARY HYGIENE. and blankets — should be taken on deck and sunned for at least an entire day. The clothing worn by the men should be sufficient and adapted to the climate. The woolen shirt should never be discarded even in tropical seas, for ships are drafty and currents of air are always chilling. AU spare clothing and accoutrements should be kept in pkces assigned to them, and not be allowed to encumber the bunks or occupy space in a sleeping-compartment. In our naval service, the official allowance of fresh water is one gallon daily per capita. In the merchant marine, the law provides that each passenger and sailor is to be supplied with three quarts of water daily. In the British transport service, the minimum daily allowance of water is six pints out of the tropics and one gallon in the tropics. On troop-ships, how- ever, the amount of water allowed for all cooking and drinking purposes should scarcely be limited ; and this can readily be accomplished by means of the distilling apparatus with which they are nearly aU provided. The distUling apparatus of the transport Thomas is capable of providing fifteen thousand gallons of fresh water in each twenty-four hours. For distilling purposes, only clean sea-water should be employed. Under no circum- stances should the water of a filthy harbor be taken on board with a view to its distillation for drinking purposes. Should it be necessary to embark troops on vessels not equipped with means of providing an abundance of fresh water from time to time as required, the quantity stored in the tanks should be Sufficient to afford at least one and one-half gallons to each man and eight gallons to each horse as a daily allowance throughout the voyage. Water is usually stored in tanks having an individual capacity of five hundred or more gallons. Those on the Thomas have a total capacity of two hundred and thirty -five thousand gallons. Where the supply is distilled while en route, these tanks should be relatively small and more numerous, to prevent the possibility of contamination of a large amount of water through temporary fault in the condensing apparatus. Wooden tanks should never be employed except in case of emergency, since the alternate wetting and drying of the wood, with deficient ventilation, is apt to render the contained water unfit for consumption. Iron tanks, painted without and cemented within, are economical and sanitary receptacles. It would be of advantage if they could be lined, as are bath-tubs and water-closet fixtures, with the so-caUed porcelain. All tanks should be furnished with large man-holes for securing cleanliness, and thorough scrubbing and rinsing, after emptying, should be carried out as a matter of routine after each voyage. If possible, the man-hole should be so placed that natural light finds its way to every part of the tank when the cover is removed. Where water is distilled, the operation should be done at sufficiently long intervals to ensure palatability and aSration. The latter is usually left to be accomplished by the roUing of the ship ; but it may be readily brought about by the use of charcoal fil- ters, by letting the water fall from a height in a state of fine subdivision, or by allowing it to trickle over well-washed pebbles, exposed to a current of air. The fiuid in the tanks from which the supply for drinking purposes is immediately drawn should be cooled by pipes passing from the cold- storage room on the way to the ice-machine. It is scarcely necessary to say that suspected water should not be used ; or if this be unavoidable that it should be boiled before issue to the men. THE HYGIENE OF THE TEOOP-SHIP. 931 With the general adoption of artificial refrigeration, the question of food on board ship, formerly a most serious problem, is now satisfactorily solved. With an abundant supply of fresh meat and vegetables, scurvy is no longer to be feared. The diet should be in no wise different from the ration of the soldier performing light duty in garrison, unless it be made slightly more laxative by the addition of more vegetables to overcome the natural tendency to constipation due to deficient exercise. At the outset of the voyage, to limit the amount of sea-sickness, the issue of fats should be discouraged. Where mess-rooms are not provided, aU food should be eaten on deck when the weather permits, and under no circumstances should rem- ' nants of food or soiled eating utensils be allowed to remain in a compart- ment used as quarters. It is well to require all portions of the ship to be swept after each meal, and thus at once remove the crumbs and other refuse food which is often unavoidably scattered on the decks and flooring. Before being disembarked, troops should be served with a hot meal, to limit the discomfort which might result from temporary absence of a food supply on shore or lack of preparation for their arrival. The disposal of excreta is not the serious matter on board transports that it is in military communities on shore, since all waste has only to be discharged overboard as quickly as possible; and abundance of water, for purposes of cleanliaess, is always available. Hence latrines need never become offensive, or possible sources of disease, if given a moderate amount of care. The best form of latrine for troop-ships consists of a broad, shallow trough, having a continuous and ample flow of salt water pumped up by the engines. Seats should be provided in the proportion of at least five to each hundred men. They should be made lq iudividual sections, and should be so weighted as to tip up when not in use — ^thus allow- ing the trough to be used for the reception of urine or vomitus without the liability of soiling the seats.