in tli£ Citj) of ilehj |9orfe V^^P ^diotil of Bental anb o o z Pn M n w r, ^ o W o ^ w ^ 0- UJ ^m in h s is ' B < o f^ w -J g>H < § X §5 u w _J g w D Q M pj J h o ^^ B Z D Eh -3 « O n >: H gl^'S l^-9'O 1?? i?* INFLUENCE OF SEASON UPON MORTALITY. 19 ■■■■■■■llliiiiiiiiiiiiiiiiiiiiiliiiiilllliiiiiiiliiiii llllllllllliiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiMttiliiiill 8SwS.>Si? i^& S 20 TEXT-BOOK OF HYGIENE. 1 1 1 1 1 1 1 1 1 f 1 1 i^^^S :::::::::::::::::::::::::::::::y - -- - - ----- ,^i II II 11$ Jill lipi ri^i iiiillili ]||y|p^||| i lll^^l^^l^ll^^^B ^^lippiii^iii^l^H . M ^^^^^^^^^^^^^^^^^^^^ in , 1 1 ^^^^^^^^^^^^^^^^^^^^ in ,,,Ji ^^^^^^^^^^^^^^^^^^^^^^ di ....J 1 ^^^^^^^^^^^^^^^^^^^^^^ ^ -r* „ . Illsl^ys^* ^^^^^^^P 1 ^^s^ ^ ^ S ;:;:,,J 1 ^^^^^^P \vi ' + ^^l*^^ 1 ^ ^ i ^^^^^^g ^«W«5. ^§1 ■:ttlll;§§iPii»iiiiiiiiiliiiiiiiin IWPiPlliiiiMiiiiiili^Miiiii Q . ^^^^^^^^^^^^^^^^^^^^^^^ M "" 1 TI^^^^^^^^^^^^^^^^^^^^^p iii^^iii|li|ii J . . . ^ ^|s T|y o 1|^| ^ II X 11 /v .. 1 i| .rf* II •^ ^ ! 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J: "? 1 4 ^ I'^'o^w INFLUENCE OF SEASON UPON MORTALITY. 21 22 TEXT-BOOK OF HYGIENE, ^ 1 ^ ^iiil ^^^^§ ^ili ^Pli ^ ^11 ^^^^S§ ^^^ siiil ^IIJI ^^^^ ^^ ^iii ^ ^i ^1*^ ^^P ^1 , ^ ^^ iliil ^iili ^^^^ 'i??;!^ ^^p !^ ^11 ihi ^^ ^iiil §^#^ ^i^^ ^tl ^ iii rtW ^^i §ii# ^^^i ^T 1^^ ^ ill iliil ^^^ i P lllll ^llll $^^ ^^i 1 i^^ iiili ^^ _^li lllll ^^^^ ^iii 1 i^^ iiiii ^^^ M ^^ ^ ^p^l §i^i^ ^^^^ ^lii P p^i^ ^^^ illl ^ Hi Iliil «l^^ ^^^ 11^ lil^l 5^^ liii ^ i^ p^i^ iii^ ^^^ Dill 1^^ liii ^ i^ lllll i^« ^^^ D - O D Z < : < ^^^ ^111 i ^^i Iiiii ^^^ liii ^ ill Bill ^^^ g § ^Ml ^ III ^^tt^ ^^^ ^ III im ^^» ^^^ 1 ii^ ^p^^ lllll ^^^ m^ ^s§^^ ^^^ 1 d 11^ iiSi i^iii ^^^ 11 111^ ^11^^ ^^^ 11 i|Bi ^1 ^^^ ^iiil ^^ ! ill lllll ^^^ H li^ i«i ^^^ 1 i^pi ^^^ 1^ ^^p ^^^ ill ^^p ^^^ f| 1 iii ii^S ^^^ i 1 III ^a ^^ j^^ ^^^ ^^ ^^^ r PL 5 ^ ^ i^i i III ^^^ ^^^ ^ ^^^ ^ f^ 1^^^ ^ ^il ^^^ ~ i^ SSjS ^£i ^ fti ^^^ ~ i^B ^ iii i^i^S^^^ ^^^ ~ jii i iii ^^ 1^ » illl i ^i ^^ i ^i 1^^ ^ ii^ ^^^ 11^ ^ iiP ll^i ^^^ ~ iil ^ ill iiBi ^^^ ~ ~ ~' lll^ ^^ ^iii ^ iii i^#^ ^^^ III liii i ii^ iliil ^^ 1$ ^ii^ 1 li lllll ^^^ 1^^ ^^1^^ ^^^ Mii iii^ ^^ ^ ^^^ ^^^ ^1^ i 111 iiH ^^^ iii^ §^^1 ^1^ liii 1 ^^^ i^^l ^^ ji^ ?ii^ llll ;$ ^ l(l 1 III ^^^ |||s §^ ^^^ 1^ ^11^ liii 1 III ^^» ^^^^ ^^ III 818 lll$ li^ ^^^ l^il pil^ ^^^^ liii 1 III ifi ^S ^^i^ ^^^^^ p^§ ^^^^ ^^^ i ^i ii ^; H S-^' -S-g5'§ «i^^' ^^s s s' I&&5 i5.i^'> 3-SJ5««, f^-^cQ*? il^j a; > < s Z 3 OJ <0 < S - "5 ,^ ™ SANITARY RELATIONS OF IMPURITIES IN AIR. 23 the maximum in July and August, the minimum from December to March; from diphtheria, tlie maximum in December, the minimum in August;^" from whooping-cough, maximum in September and February, minimum in November and June; for croup the curves agree pretty closely with the diphtheria curves; from phthisis, the maximum in March, minimum in June. Tlie foregoing charts, reproduced by permission of the Massachu- setts State Board of Healtli from the report of that body for 1888, show an ahnost identical movement of the mortality from different diseases throughout the year. They exhibit the reported mortality for 1888 and also for the six years from 1883 to 1888. From suicide, curiously, the greater number of deaths occurs in May, the smallest in February. This is contrary to the usual suppo- sition that gloomy weather predisposes to suicide. The six summer months — from April to September — sho\\: a much larger number of self-murders than the remaining half-year. In eleven years, ending 1880, there were 1521 cases of self-destruction in Few York. Of these 341 occurred during January, February, and March; 417 dur- ing April, May, and June; 412 during July, August, and September; and 351 during the last three months of the year. In Philadelphia, the results of examination of the statistics of suicide for ten years are almost exactly similar. Out of 636 cases of suicide, 78 occurred in May, 71 in August, 57 in December, 54 each in October, July, and April, 52 in June, 49 in ISTovember, 44 each in December and Feb- rurary, 43 in March, and 36 in January.^'' Dr. Lee is led to believe that "a low barometric pressure, accompanied by a high thermometric registry, with sudden fluctuations from a low to a high temperature, together with much moisture and prevailing southwest winds, might somewhat account for the frequency of self-murder in the spring and summer months." THE SANITARY RELATIONS OF CHANGES IN COMPOSITION AND OF IMPURITIES IN THE AIR. The average proportion of carbon dioxide in the atmosphere is from 3 to 4 parts in 10,000. Pettenkofer^'^ places the maximum limit ^'' See paper on the Relation of Weather to Mortality from Diphtheria in Baltimore, by Richard Henry Thomas, in Trans. Med. and Chir. Faculty of Maryland, 188.3. " Suicide in the City and County of Philadelphia durinjj; a Decade, 1872 to 1881, inclusive, by John G. Lee, Trans. Am. Med. Asso., vol. xxxiii, p. 425. "Quoted in Buck's Hygiene and Public HealJi, vol. i, p. 615. 24 TEXT-BOOK OF HYGIENE. of carbon dioxide allowable in the air of dwellings at 7 parts in 10,000, It is probable that this limit is very frequently exceeded without serious consequences to health, if the air is not at the same time polluted by organic impurities, the products of respiration. Professor William Eipley Nichols found the air in a school-room in Boston to contain eight times the normal proportion of carbon di- oxide, while Pettenkofer found, also in a school-room, after the same had been occupied two hours, eighteen times the normal proportion, or 73 parts in 10,000.^^ While such an excess of this poisonous gas must unquestionably have an unfavorable influence upon health, it is probable that the most serious effects are due to the coincident diminution of oxygen and the pollution of the air by the products of respiration which necessarily take place during respiration. Carbon dioxide alone may be present in the air to a much greater extent than above mentioned without causing any appreciable inconvenience. In the air of soda-water manufactories there is frequently as large a proportion as 2 per cent, of this gas present without producing any ill effects upon those breathing such an atmosphere. The amount of carbon dioxide in the atmosphere is greatest at night. It is also greater very near the ground than at a distance of several feet above it. As carbon dioxide is absorbed by the leaves of plants during the day-time, but given off at night, the difference may partly be thus accounted for. According to Fodor,^° the source of a large proportion of the carbon dioxide in the air is the decomposition going on in the soil. This accounts for the larger percentage of car- bon dioxide near the ground. This would also explain the variation of the proportion of carbon dioxide in the air under different meteoro- logical conditions. For example, it is found that during rainy weather the carbon dioxide in the air is diminished. This is accounted for partly by the absorption of the carbon dioxide by the saturated ground, while at the same time the porosity of the soil is diminished and the escape of the ground-air prevented. Mr. R, Angus Smith made a number of experiments upon him- self to determine the effects of an atmosphere gradually becoming charged with the products of respiration and perspiration. His ex- periments were conducted in a leaden chamber holding 5 cubic metres of air. This air was not changed during the experiment. After re- maining for an hour in this chamber, an unpleasant odor of organic ^° See table in Buck's Hygiene and Public Health, vol. i, p. 612. ^° Hygienische Untersuchungen ueber Luft, Boden und Wasser, Braum- schweig. 1882 2te Abth. SANITARY RELATIONS OF IMPURITIES IN AIR. 25 matter was perceptible on moving about. The air, when agitated, felt soft, owing, doubtless, to the excess of moisture contained in it. The air soon became very foul, and, although not producing any discom- fort, the experimenter states that escape from it produced a feeling of extreme pleasure, like "that which one has when walking home on a fine evening after leaving a room which has been crowded."-^ Hammond^ ^ confined a mouse in a large jar in which were sus- pended several large sponges saturated with baryta water, to remove the carbon dioxide as rapidly as formed. Fresh air was supplied as fast as required. The aqueous vapor exhaled was absorbed by cal- cium chloride. The mouse died in forty-five minutes, evidently from the effect of the organic matter in the air of the jar. The presence of this organic matter was demonstrated by passing the air through a solution of potassium permanganate. The horrible story of the 'Hslack hole" of Calcutta is familiar to every one. Of 146 prisoners confined in a dark cell at night, 23 were found alive in the morning. Among the survivors a fatal form of typhus fever broke out, which carried off nearly all of them. After the battle of Austerlitz 300 prisoners were crowded in a prison; 260 died in a short time from inhaling the poisoned air. iSTumerous other similar examples of the effects of polluted air are recorded. Usually the effects of foul air are not so sudden and striking. In m.ost instances, especially where the pollution has not reached a high degree, there simply results a general deficiency of nutrition, which manifests itself in anemia, loss of vigor of body and mind, and a gradual diminution of resistance to disease. It seems to be beyond question that persons who are constantly compelled to inhale impure air, especially if combined with an im- proper position of the body or lack of sufficient or appropriate food, furnish a very large percentage of chronic pulmonary affections. Phthisical patients, in the overwhelming majority of cases, are drawn from the classes whose occupations keep them confined in close rooms. Want of exercise and of good food doubtless aid in the de- velopment of the lung disease. Formerly, when less attention was paid to the proper construction and ventilation of barracks and prisons, the mortality from phthisis among soldiers and criminals was much greater than it is now. In animals kept closely confined the same disease claims a large share in the mortality. ^Air and Rain, p. 138. ^ A Treatise on Hygiene, with Special Reference to the Military Service, by William A. Hammond, M.D., Surgeon-General U. S. Army, p. 170. Phila- delphia, 1863. 26 TEXT-BOOK OF HYGIENE. Near the end of the last century over one-third of the infants born in the old Dublin Lying-in Hospital died of epidemic diseases. After the adoption of an improved system of ventilation the mor- tality fell to about one-tenth of what it had previously been. To illustrate the effect of similar conditions upon the health of domestic animals, the following instance is cited: Upward of thirty years ago a severe epidemic of influenza in horses appeared in Boston. At the instigation of Dr. H. I. Bowditch, every stable in the city was in- spected, and classified as "excellent," '^imperfect," or "wholly unfit," in respect to warmth, dryness, light, ventilation, and cleanliness. It was found that in the first class fewer horses were attacked and the disease was milder, while in the third class every horse was attacked and the more severe and fatal cases occurred. Carbon monoxide is a very dangerous impurity often present in the air of living-rooms. Being an ingredient of illuminating gas, as well as the so-cal'ed coal-gas which so frequently escapes from stoves and furnaces, its dangerous character becomes apparent. Many per- sons die every 3'ear in this country from the inhalation of illuminating gas. People unacquainted with the mechanism of gas-fixtures fre- quently l)low out the light instead of cutting off the supply of gas by turning the stop-cock. It is also a prevailing custom to keep the light burning "low" during the night. Any considerable variation of pressure in the pipes, or sudden draught, may put out the light and permit the gas to escape into the room, with fatal effect. Leaks in pipes or fixtures may have the same results. Chronic poisoning with minute quantities of illuminating gas is very common, especially in large cities, and many cases of obscure anemia and ill-health are due to this cause. Coal-, coke-, or charcoal- fires may produce serious or fatal poisoning if the gas, which contains a large proportion of carbon monoxide, is permitted to escape into the room.^^ In certain parts of Europe, notably in France, the inhalation of the fumes of a charcoal fire is a favorite method of committing suicide. The gas which sometimes escapes from the stove when coal is burning has the following composition : — Carbon dioxide 6.75 per cent. Carbon monoxide 1-34 Oxygen . 13.19 Nitrogen 78.72 ^ See paper bv Dr. John Graham in Transactions of Philadelphia College of Physicians for 1885. SEWER-AIR. 27 Sulphuretted and carburetted hydrogen, are not infrequently present in the air, especially about cess-pools and in mines and certain manufacturing establishments. Sulphuretted hydrogen is generally considered to be a violent poison, but there is no evidence that it is so unless oxygen is excluded. Carburetted hydrogen is the so-called "fire-damp" of mines, which is so often the cause of fatal explosions. Its inhalation does not seem to be especially noxious. It will be more fully referred to in a succeeding chapter. Variations in the proportion of ammonia present in the air are frequent. Its presence is an indication of organic decomposition in the vicinity, but nothing is known of the influence of the gas itself upon health, in the proportion in which it is ever found in the atmos- phere. SEWER=AIR. Sewer-air, or sewer-gas, as it is often improperly called, is a vari- able mixture of a number of gases, vapors, atmospheric air, and solid particles, and is derived from the decomposition of the animal and vegetable contents of sewers. A number of analyses by different chemists have shown that the composition of sewer-air is extremely variable. The most important components, in addition to the con- stituents of atmospheric air, are: Carbon dioxide, ammonia, sul- phuretted hydrogen, and a number of volatile organic compounds, which give to sewage its peculiar odor, but which are present in such small quantity as to prevent accurate determination by chemical means. Sewer-air may also contain particulate bodies, bacteria, and other microscopic organisms, which may be the active causes of in- fectious diseases. Some recent researches by Carnelly and Haldan^ have shown that sewer-air usually contains a less number of micro- organisms than the external air of cities. The proportion of carbon dioxide found was a^so much less than was expected. When the con- tents of sewers remain in these receptacles or conduits long enough to undergo decomposition, sewer-air is always present. The continual breathing of air polluted by emanations from sew- ers often produces more or less serious derangements of health. Diarrhea and other intestinal affections and mild cases of continued fever have been frequently noted in connection with defective sewer- age, and the escape of sewer-air into inhabited rooms. The effluvia from cemeteries, knackeries, and other places where the bodies of animals are undergoing decomposition, are popularly 28 TEXT-BOOK OF HYGIENE. regarded as deleterious in their effects upon health. The evidence in favor of this view is, however, very indefinite. Professor Tyndall has shown-* that even the apparently clearest air is, when in motion, constantly filled with innumerable particles of dust, which are the carriers of various micro-organisms. The pres- ence of these particles can be easily demonstrated by means of the electric light. Every one has observed these minute particles in a bright ray of sun-light. Under ordinary conditions these particles of dust would, of course, give rise to no trouble, but if intermingled with these dust-specks there were disease germs, then manifestly the inhalation of such "dust" would be dangerous.^^ The quantity of dust found in the air of cities is much greater than in the country. Tissandier found that in Paris the percentage of dust was eight to twelve times greater than in the open country. One-fourth to nearly one-half of this atmospheric dust is organic, either animal or vegetable. A-^ery recent observations have shown that in Paris the air contains nine or ten times as many bacteria in a given volume as the air at the observatory of Montsouris, just without the city. The relative proportions of organic and inorganic particles vary as 25 to 75 in Paris, 45 to 55 in Dublin, and 25 to 75 in the open country. The organic particles are either particles of dead organic matter, or minute organisms. The proportion of the latter varies in different seasons, being the least in winter and spring, and greatest in summer and autumn. These organisms are not necessarily patho- genic, but the conditions which favor the proliferation of non-patho- genic bacteria are likely to promote the development of disease-pro- ducing ones likewise. Among the pathogenic micro-organisms which may be found in the atmosphere are spores of achorion Schoenleinii, streptococci, staphyloccoci, the bacilli of tuberculosis, cholera, and typhoid fever, and other- micro-organisms which produce disease. It is advisable in all cases to exhaust the stagnant air in old wells and privy- vaults before permitting any one to descend. Per- haps the readiest method of exhausting the vitiated air in such places would be to lower heated stones, masses of hot iron or pails of hot water, to near the bottom, which produce a rarefaction of the air and cause it to ascend. Its place will then be occupied by purer air from without. The rarefaction produced by the explosion of gun-powder ^•* Essays on Floating Matter of the Air. New York, 1882. ^ See Chapter IX, on Industrial Hygiene, for eflfects of inhalation of dust in various industries. THE EXAMINATION OF AIH. 29 has also been made use of with success; but this has some objections, because the combustion of powder itself produces gases which are noxious if breathed in large quantity. An animal, such as a eat or dog, should be first lowered into the suspected well for fifteen or twenty minutes, in order to determine whether the air at the bottom is capable of sustaining life, before permitting the workmen to descend. Similar precautions should be used in old, long-unused mines to prevent fatal effects from the so-called "choke-damp," which is largely composed of carbon dioxide. THE EXAMINATION OF AIR. Occasions often arise wherein physicians or others desire infor- mation concerning the atmosphere of apartments or confined spaces. They have neither time, apparatus, nor, possibly, the skill necessary to obtain the accurate results of the expert chemist or bacteriologist; nor do they require that the information which they seek should be so extremely exact. In the preparation of this chapter, therefore, such methods of procedure will be detailed as will serve to determine, with reason- able accuracy and with moderate requirements of time, expense, or technical skill, the hygienic condition of the substances examined. The apparatus and reagents will also be found, for the most part, to be cheap and easily obtainable, and they may often be improvised or prepared from material already at hand. Moreover, a little thought will show how a number of these methods may be developed along the line of greater accuracy, should this be desired, and the principles involved will indicate how similar examinations may be made of other phases of the respective subjects not herein discussed. The substances in the atmosphere whose proportions or charac- teristics it may be important to determine are : the aqueous vapor ; ozone; suspended particles, both organic and inorganic; living micro-organisms; volatile organic matters, and the various gases given off as products of respiration, combustion, etc., or in the course of certain manufacturing processes. The proportion of aqueous vapor is to be determined by some form of hygrometer, such as Lambrecht's polymeter, or from the readings of wet- and dry- bulb thermometers, which readings, when applied to Glaisher's tables, furnish a means of determining the relative and the absolute humidity, the dew-point, the weight of water to a given volume of air, etc. 30 TEXT-BOOK OF HYGIENE. The presence of ozone in the atmosphere may be demonstrated by exposing to the air strips of white blotting- or filter- paper which have been saturated with a solution of potassium iodide and starch and dried. The ozone, decomposing the potash salt, liberates the iodine and colors the starch blue. During the test the paper should not be exposed to dust, rain, wind, or the direct rays of the sun. Another test (Houzeau's), perhaps even more delicate, is to dampen a strip of faintly-red litmus-paper with a solution of the iodide and dry. The action of ozone upon this is to liberate the alkaline potash and change the litmus to blue. As ammonia is the only other gas likely to produce the same coloration, if another strip of the litmus-paper, not moistened with the salt, be exposed at the same time, whatever difference in shade there may be in the papers is due to the ozone. An idea of the quantity of ozone present may also be gained by com- paring the shade of blue given by either test with that produced in similar strips of the starch- or litmus- paper, respectivelj^, which have been exposed to certain definite amounts of ozone, a series of such papers forming a standard of comparison. It may be suggested, for still another test, that a definite quantity of the air to be examined be drawn through a faintly-acid solution of the potassium iodide, phenolphthaleine being used as an indicator. As soon as sufficient alkali is liberated to neutralize the acidity, the pink color of the phenolphthaleine will be developed and will deepen as the proportion of free alkali increases. Here, also, a control-test to eliminate the influence of ammonia should be made by drawing a similar quantity of air through the same amount of the solution minus the potassium iodide. As before, the difference in color- shading will be proportional to the amount of ozone in the air, Numerous methods have been suggested for the collection of the solid impurities of the atmosphere, varying according to the kind or extent of examination to which they are to be subjected. If they are simply to be studied microscopically, glass slides coated with glycerin and exposed to the air will be sufficiently covered after several hours, or they may be collected more rapidly by aspirating large quantities of the air against such slides or through tubes coated interiorly with glycerin, as by means of Pouchet's aeroscope or by the apparatus de- vised by Dr. S. G. Dixon. This latter is especially advantageous where it is desired to collect samples of dust in the air of a number of localities within a short time, and consists essentially of a double cylinder of metal, within which is a rack carrying a number of glycerin- or gelatin- smeared cover-glasses. By an ingenious arrange- THE EXAMINATION OF AIR. 31 ment the air can be aspirated by means of a hand-bulb over each of these glasses in turn, the dust particles being deposited on the sticky surface, and thus the samples may be taken from as many localities as there are cover-glasses. Moreover, the specimens may be mounted and examined as they are, may be stained, or, if the glasses be coated with gelatin and the whole apparatus be sterilized ])efore the collec- tion, colonies of the bacteria, etc., in the dust may be allowed to de- velop on the glasses and be studied in loco under the microscope. Another satisfactory method of collecting suspended particles is to draw a considerable volume of air very slowly through a small quantity of distilled water contained in one or two wash-bottles. The solid particles may then be allowed to settle, and subsequently be removed for microscopical examination by means of a pipette, or the whole may be filtered and the weight of the dust in the aspirated air thus obtained. It might also be well, in the latter case, to evaporate the fi'.trate to dryness and to determine what proportion of the residue is organic matter, and what are its nature and effects when administered to animals. Lastly, the air may be slowly drawn through a small tube packed with pure sugar, the sugar afterward being dissolved in distilled water, whence the .solid particles taken from the air may be removed by means of a pipette or by filtration. The physical nature of the particles of dust thus collected is to be determined by means of the microscope, it being presumed that the examiner is sufficiently familiar with the instrument to recognize at sight the more common materials that are apt to. pervade the air of occupied apartments, such as bits of cotton, wool, hair, epithelium, etc. Charring on ignition will indicate that the residue is, at least, partly organic, and the odor of burnt feathers that it is nitrogen ous and probably of animal origin. Suitable chemical tests will also de- termine the presence or absence of suspected substances. Thus, an examination of the dust by Marsh's or Eeinsch's test may reveal the presence of arsenic, and lead to an investigation as to its source. However, since Cornet and others have demonstrated that the micro-organisms in the air are, in general, closely adherent to the dust-particles, a bacteriological examination of the latter will, except in special cases, be of more importance than a physical or chemical one. To make a qualitative bacteriological examination it is only necessary to coat the glass plates or tubes, already described, with nutrient gelatin instead of glycerin, and to sterilize them before use. They are then exposed to the air as before, covered, and set aside in 32 TEXT-BOOK OF HYGIENE. Fig. 1. — Organic Matters Frequently Present in Dust. 8, Fibers of Silk; C, of Cotton; L, of Linen; W, of Wool. F, Feather. St, Starch-granules. Cr, Cork. 0, Torulse. M, Mycelia, or Threads, of Mildew. Mc, Micrococci. B, Bacteria. Lt, Leptothricial Filaments. (After Heitzmann.) X 500. a place of proper temperature to allow the colonies to develop from the various micro-organisms which have adhered to the sticky sur- faces; or Dr. Dixon's apparatus, with gelatin-coated glasses, may be used in the manner described. THE EXAMnsTATION OF AIR. 33 A quantitative bacteriological examination is almost as readily made by drawing a given quantity of air through a sugar-filter, as stated. The tube should not be too large in diameter nor in length, should be filled with pure granulated sugar and the ends temporarily plugged with cotton, and should, of course, be sterilized before mak- ing the test. After the air has been drawn through it the sugar is carefully emptied into tubes or flasks of nutrient gelatin, which have been heated just enough to melt the gelatin, but not sufficiently high to kill the bacteria, etc., which have been caught in the sugar. The latter rapidly dissolves and leaves the micro-organisms free to de- velop in the gelatin, which may be poured out before cooling upon sterilized glass plates or into shallow (Petri) dishes. So-called col- onies rapidly develop from the individual bacteria, and the total num- ber of these colonies may be assumed to represent the number of micro-organisms in the quantity of ajr aspirated through the filter. Moreover, from these colonies pure cultures may be made, and the nature, etc., of the respective microbes determined. To determine the quantity of organic matter in the air the most feasible method is to slowly draw a certain volume of air through a given quantity of twice- distilled ammonia-free water, which retains not only all the volatile and suspended organic matters, but also the gases originating there- from. The water is then to be tested by the Wanklyn process for "free" and "albuminoid" ammonia, and, if desired, by the Tidy- Forehammer process for oxidizable organic matter, though it should be noted that in the latter process other gases present in the air, such as sulphuretted hydrogen, may help to decolorize the permanganate solution, and must therefore be excluded or estimated separately. However, as these processes are, perhaps, too complex for the purpose of this chapter, and as it has been shown by de Chaumont and others that the organic matter with which we are usually most con- cerned — namely, that given off from human bodies as a product of respiration and like processes — is produced in quantities proportional to the amount of carbon dioxide eliminated in the same processes, it generally suffices for our purpose to determine the proportion of this gas in the atmosphere, especially as this determination is much more readily made than the foregoing one. The methods devised by Wolpert and Angus Smith for rapidly estimating the percentage of carbon dioxide have been materially simplified by Professor Boom. Professor Boom has suggested that, instead of the special and somewhat expensive apparatus of Professor Wolpert, a mark be made 34 TEXT-BOOK OF HYGIENE. on any test-tube, — say, one inch from the bottom. Fix the bulb of any atomizer to a small glass tube — a capillary one, if possible — suffi- ciently long to reach the bottom of the test-tube, and in such a man- ner that a definite volume of air is driven from the atomizer-bulb through the tube at each compression of the former. In using, fill the test-tube exactly to the mark with a clear, saturated solution of lime-water, and find how many compressions are needed in the out- door air — forcing the air through the lime-water each time and taking care not to draw any fluid up into the bulb — to make the fluid Just turbid enough to obscure a pencil-mark or print on white paper placed beneath the test-tube and viewed from above. Clean the test-tube thoroughly, and repeat the process in the apartment of which the air is to be examined. As- suming that the out-door air contains the normal proportion of carbon dioxide, — ■ viz., 0.04 per cent., — the percentage in the air of the room is determined as follows: The numljer of compressions of the bulb in the out-door air : the number of compressions in the room :: x : 0.04 per cent., x representing the percentage of carbon dioxide in the air of the room. As a modification of the Angus Smith method, the author would suggest the fol- lowing as being, perhaps, more accurate, and as certainly not requiring so much apparatus, etc. : — To a wide-mouthed bottle, holding about a quart or litre, fit a doubly-per- forated rubber stopper, one perforation being just large enough to receive the tip of a 1 c. c. pipette, the other carrying a small test- tube, its mouth opening into the jar and close to the inner surface of the stopper. Fill the bottle and test-tube with the air of the room by filling them with water and emptying; fit in the stopper, and introduce, by means of a 1 c. c. pipette, a cubic centimetre at a time of a standardized alkaline solution, slightly colored with a few drops of a neutral alcoholic solution of phenolphthaleine. Close the pipette perforation in the stopper with a bit of glass rod and shake the bottle well each time after adding the alkaline solution. Con- tinue in this way until the color is no longer discharged by the acid -Ji Fiff. 2. ^0 -Air-tester. THE EXAMINATION OF AIR. 35 carbon dioxide of the air. By having the test-tube fitted in the stop- per as above and inverting the bottle, the same thickness of fluid is observed each time, and there is more accuracy tlian if the bottle is used without the test-tube. In either ease the fluid should be ex- amined by looking through it against a white light or surface. ISTow, since the quantity of the alkaline fluid used indicates a cor- respondingly definite amount of carbon dioxide, — the number of c. c. of solution used X the volume of C0« each c. c. represents X 100 the capacity of the bottle and test-tube in c. c. — the number of c. e. of solution used = the percentage of carbon dioxide in the air examined. A suitable alkaline solution may be prepared by dissolving ex- actly 4.766 grammes (73.549 grains) of pure anhydrous sodium car- bonate in 1 litre (35.238 fluidounces) of distilled water. Each cubic centimetre of this solution is equivalent to a like volume of carbon dioxide. To 10 cubic centimetres of this solution add a few drops of a neutral alcoholic solution of phenolphthaleine and dilute with dis- tilled water to 100 c. c. Each cubic centimetre of the dilute solution will now be neutralized by 0.1 of carbon dioxide, and, if used as sug- gested, should give close results. The phenolphthaleine is used as an indicator, as it loses its color as soon as the alkalinity of the soda solution is destroyed by the carbonic acid. Example: If 11 c. c. of the foregoing dilute solution be nsed, and the capacity of the bottle and test-tube is 1153 c. c, then 11 X 0.1 X 100 110 = = 0.0963,— 1153 — 11 1142 the percentage of carbon dioxide in the air of the apartment. The first (stock) solution must be kept in well-filled and tightly-stoppered bottles, and the dilute solution made up as needed. Pettenkofer's method for determining the percentage of carbon dioxide in the air, which is usually considered the best, is as follows : Into a large, clean bottle or Jar, filled with the air of the room as on page 34, introduce 50 c.c. of a clear, saturated solution of lime (cal- cium hydrate), stopper the bottle, and shake it well, so that the air may be well washed by the lime-water. This shaking should be re- peated at intervals for several hours, from eight to ten hours being required for the lime-water to absorb all the carbon dioxide in the air in the jar. (However, if baryta — ^barium hydrate — ^water be used instead of the lime-water, the absorption will be completed in an hour.) 36 TEXT-BOOK OF HYGIENE. The strength of tlie lime- (or baryta-) water being unknown and variable, it is determined by means of an oxalic-acid solution of such strength that 1 c. c. corresponds in acidity to 0.5 c. c. of carbon dioxide. Such a solution is made by dissolving exactly 2.84 grammes (43.837 grains) of pure crystallized oxalic acid in 1 litre of freshly- distilled water. This acid solution is run into 25 c. c. of the lime- water in a beaker from a graduated burette, or pipette, until the al- kalinity of the lime is just neutralized, the neutral point being indi- cated either by means of a few drops of a neutral phenolphthaleine solution in the beaker or by turmeric paper, the latter being colored brown, and the phenolphthaleine retaining its color as long as the solution is alkaline. When the lime is exactly neutralized the amount of the acid solution used from the burette is noted. Then 25 c. c. of the lime-water from the testing-bottle is meas- ured into a beaker, and its acidity determined in the same man- ner by means of the oxalic-acid solution. Now, since part of the lime in the solution in the testing-bottle has already been neu- tralized by the carbonic acid of the air therein, it will require less of the acid solution to neutralize the lime-water from the bottle than it did to neutralize the same quantity from the stock solution, and the difference will indicate the exact amount of carbon dioxide in the air in the testing-bottle. For, though each cubic centimetre of acid solution is equivalent to only one-half cubic centimetre of carbon di- oxide, the loss of alkalinity of only lialf the lime-water in the bottle has been determined, and the total loss would be expressed by twice the difference found. The number of cubic centimetres of carbon dioxide in the air in the bottle having been thus determined, and the capacity of the bottle found by measuring the quantity of water it will hold, the percentage of carbon dioxide in the air is readily de- termined. For example: 25 c. c. of stock lime-water requires 30 c. c. acid solution, and 25 c. c. of lime-water from testing-bottle re- quires 27 c. c. acid solution; therefore, 30 — 27 = 3 c. c, — the amount of carbonic acid in the bottle, which contains, say, 2250 c. c. Then— 3 X 100 300 = = 0.12- 2550 — 50 2500 the percentage of carbon dioxide in the room at the current temper- ature and pressure. It should be noted that the accuracy of all these tests is somewhat vitiated by other acid gases, if present in the air, and due allowance should be made wherever they are suspected. THE EXAMINATION OF AIR. 37 As has been intimated, baryta-water may be used in place of the lime-water, being more rapid in action, but considerably more ex- pensive, than the latter. The solution should be made of the strength of about 7 grammes of crystallized barium hydrate to the ' litre of distilled water; it must not be forgotten, also, that it is poisonous when taken internally. A good indicator, in addition to the phenol- phthaleine and turmeric, is methyl-orange, which is yellow in alka- line and of a reddish tint in acid solutions. The quantity of ammonia in the atmosphere may be determined by drawing a certain volume of air through ammonia-free water and then "Nesslerizing" the latter, as in the Wankl}Ti process of water analysis. So, also, the presence and percentage of other gases, such as nitric, hydrochloric, sulphurous, and sulphuric acid, sulphuretted hydrogen, ammonium sulphide, etc., are obtained by drawing the air through distilled water and subsequently making the proper chemical tests. For instance, the sulphur gas will darken a solution of lead acetate and ammonium sulphide will change the blue color of nitro- prusside of sodium to violet; consequently, the air may be drawn through standard solutions of these reagents and the resulting col- oration compared with that produced by known quantities of the re- spective gases. The presence of carbon monoxide is shown by the darkening of a solution of palladium chloride or sodio-chloride, but a more deli- cate test is that of Vogel by means of the spectroscope, which will show the presence of as little as 0.03 per cent, of the gas. In this test a drop of fresh blood is mixed with a little pure water and the mix- ture well shaken with a sample of the air in a jar. Then a few drops of ammonium sulphide are added and the fluid examined spec- troscopically. If carbon monoxide is present the spectrum of oxy- hemoglobin will be seen, it not having been reduced by the ammo- nium sulphide; but if the carbon monoxide is not present, we shall have the spectrum of reduced hemoglobin. As even very small quantities of carbon monoxide in the air are harmful, it will not often be necessary to make a quantitative test for it ; but should this be desired, it can be done by passing a given volume of air several times through a solution of subchloride of copper, wh-ich absorbs the carbon gas, and then determining the loss of vol- ume the air has suffered by means of the eudiometer. 38 TEXT-BOOK OF HYGIENE. PRINCIPLES OF VENTILATION. During ordinary respiration an adult human being adds 900 graromes ^ 455,500 cubic centimetres (14 cubic feet) of carbon di- oxide to, and abstracts 744 grammes = 516,500 cubic centimetres (16 cubic feet) of oxygen from the atmosphere in twenty-four hours. Hence, if the individual were confined in an apartment where the inclosed air could not be intermingled by diffusion with the atmos- phere without, the proportion of carbon dioxide would soon become so great that the processes of life could not- be sustained, and the in- dividual would die. This result would be reached even sooner than the point here mentioned, for the organic matter exhaled from the lungs and the surface of the body would increase the poisonous con- dition of the air even more than the carbon dioxide given off. It is easily seen, therefore, how important the study of the principles and practice of ventilation becomes in hygiene. In this chapter only the principles underlying this subject can be definitely stated. Practical details will be more fully given in the chapters devoted to dwellings, schools, hospitals, etc. It is generally accepted among sanitarians that the presence of .07 per cent (7 parts in 10,000) of carbon dioxide in the air indi- cates the greatest amount of organic impurity (from respiration or combustion) consistent with the preservation of health. As each in- dividual gives off from his lungs, in the process of respiration, 316 cubic centimetres of carbon dioxide per minute, the diffusion in the air surrounding him must be sufficiently rapid to keep the air to be breathed at the standard of .07 per cent, above mentioned. Adopting this as the standard of maximum impurity allowable, 90 cubic metres of fresh air per hour will be needed for each indi- vidual to keep him supplied with pure air. This is for a person in a state of health ; in cases of disease a more rapid change of air will be necessary to keep that surrounding the patient in a state of purity. Ventilation is defined by Worcester as "the replacement of nox- ious or impure air in an apartment, mine, or inclosed space by pure, fresh air from without." By Dr. Parkes the term is restricted to "the removal or dilution, by a supply of pure air, of the pulmonary and cutaneous exhalations of men and the products of combustion of lights in ordinary dwellings, to which must be added, in hospitals, the additional effluvia which proceed from the persons and discharges of the sick. All other causes of impurity of air ought to be ex- PRINCIPLES OF VENTILATION. 39 eluded by cleanliness, proper removal of so' id and liquid excreta, and attention to the conditions surrounding dwellings."-*' A proper system of ventilation must take into consideration the cubic space of the apartment or building to be ventilated, the num- ber of persons ordinarily inhalnting this space, whether constantly or only temporarily occupied, and certain other collateral elements, such as the character of the building to be ventilated, its exposure, neces- sity for artificial heating, etc. The amount of cubic space that must be allowed to each indi- vidual is determined by the rapidity with which fresh air must be supplied in order to keep that surrounding the individual at the standard of less than .07 per cent, of carbon dioxide. For example, in a space of 3 cubic metres, the air must be changed thirty times in an hour in order to prevent the carbon dioxide exceeding the above proportion; that is to say, to allow 90 cubic metres of air to pass through that space in the time mentioned. This would create an uncomfortable, if not injurious, draught. If the space contained 30 cubic metres, the air would need renewal only three times an hour. A space of 15 cubic metres could be kept supplied with pure air without perceptible movement if all the mechanical arrangements for changing the air were perfect; but such perfection is rarely attain- able, and hence there would be either draughts or insufficient venti- lation in such a small "initial air-space," as it is termed. The initial air-space should, therefore, be not less than 30, or, better, 40 cubic metres. The air of this space could be changed sufficiently often to keep it at its standard of purity without creating unnecessary draught. For sick persons this should be doubled. In hospitals, therefore, the cubic air-space allowed to each bed should be not less than 60 to 80 cubic metres. As stated, the purposes for which the building or apartment to Ije ventilated is employed require differences in the cubic space and in the volume of fresh air supplied. In Table III (page 40) Morin gives the cubic space for various purposes. These figures are not excessive from a sanitary standpoint, although few buildings meet the requirements here set down. The source of the air supplied must, of course, be capable of yielding pure air. It should not be drawn from damp cellars or base- ments, or from tbe immediate vicinity of -sewers or drains. Air taken '''M;inu;i,l of Practical Tlygiene, 6th cd., New York, vol. i, p. 157. 40 TEXT-BOOK OF HYGIENE. Table III Hospital wards for ordinary cases 60-70 cubic metres. Hospital wards for surgical and obstetrical cases. . 100 " " Hospital wards for contagious diseases 150 " " Prisons 50 ( ordinary occupations 60 " ( unhealthy occupations 100 " " S during the day 30 " " Barracks i ^ ■ .-, ■ ■.. ^n -n " " < during the night 40-o0 Theatres 40-50 " Assembly rooms for long receptions 60 " " Assembly rooms for brief receptions 30 " " Primary schools 12-15 " " Higher schools 25-30 " ' "' Stables 180-200 " from such places is little better for respiration than that which it replaces in the apartments to be ventilated. Ventilation may be accomplished either with or without arti- ficial aids. In buildings or rooms, used as habitations, natural ven- tilation (with, perhaps, the simplest mechanical aids) is made use of almost entirely. In large buildings, such as churches, theatres, schools, or in ships and mines, one of the artificial systems must be adopted if efficient ventilation is desired. Natural ventilation takes place by diffusion, by perflation, and in consequence of inequality of atmospheric pressure. By difl'usion is meant the slow and equable entrance of air from without and exit from within a room through the walls or ill-made joints without the influence of wind-currents. In an occupied room this is, however, insufficient to keep the air pure, because many of the organic im- purities of respired air are molecular, and, therefore, incapable of making their way out of the rooms through the walls. Perflation means, literall}^, "T^lowing through," and, if the di- rection and force of air-currents could be regulated, this would, with simple mechanical arrangements, be an efficient means of ventilation. However, the uncertainty of the force and direction of the wind makes this method of ventilation untrustworthy except in warm weather. Unequal pressure between the air in a room and that without is, within certain limits, an efficient means of ventilation, and is usu- ally relied upon in ordinary apartments. When the air in a room is heated above the temperature of the external air, either by a fire, lights, or by the presence of a number of persons in the room, it ex- PRINCIPLES OF VENTILATION.- 41 pands, and part of it finds its way out through numerous crevices and bad joints found in all buildings. The air which remains be- ing less dense than the external air, the latter enters the room by various openings, until the equality of pressure is re-established. But as the heating of the enclosed air continues, the process is mom- entarily repeated and becomes continuous. Although the impurities of respired air (carbon dioxide, or- ganic matter) are heavier than the air itself at the same temperature, it is a familiar fact that the most impure air in an occupied room is always found near the ceiling, the impurities being carried up- ward with the heated air, and that the pure air from without, being colder, fills the lower part of the room. If the cold, outside air were to be admitted at the bottom of the room, and means allowed for the escape of the hot air at the top, the conditions of the old health-maxim, to "keep the feet warm and the head cool," would be reversed. This would be no less uncomfortable than unwholesome. In all plans for natural ventilation, therefore, provision must be made to secure a gradual diffusion of the cold, out- side air from above, or to have it warmed before it enters the room. With a large chimney as an aspirating shaft,^^ with flues at the top and bottom of the room, and openings in the walls of the room near the ceiling to admit fresh air, sufficient ventilation can be usually secured in cold weather, in a room not overcrowded. When a room is heated by a furnace, the fresh air is warmed before it is introduced, and the foul air escapes either through a ven- tilating shaft, a ventilator in the window or wall, or through the numerous fissures and other orifices which defective carpentering always leaves for the benefit of the health of the occupants. The following rules for the arrangement of a system of natural ventilation are modified and condensed from Parkes-^ : — The apertures of entrance and of exit for the air should be placed far enough apart to permit thorough diffusion of the fresh air. When the air is brought into a room through slits or tubes in the walls near the ceiling the current should always be deflected upward by an inclined plane, in order to prevent a mass of cold air from descending over the shoulders of the occupants and chilling them. The air must be taken from a pure source. ^Of course there is really no such tiling as a real aspiration, or "sucking out" of the air through the chimney or so-called "aspirating shaft." The upward movement of the air in the shaft is due to its displacement by the colder or denser air entering the room. ^Manual of Practical Hygiene, 6th ed., New York, vol. i, p. 177. 42 • TEXT-BOOK OF HYGIENE. The inlet-tubes should be short, and so made as to be easily cleansed, otherwise dirt lodges and the air becomes impure. Inlets should be numerous and small, to allow a proper distribu- tion of the entering air. Externally, the inlets should be partially protected from the wind, to prevent strong draughts; they should also be provided with valves to regulate the supply of air. If the air cannot be warmed, the inlets must be near the ceiling ; if it can be heated, it ma}^ enter near the floor. The air may be warmed by passing it through boxes containing hot water or steam coils, by passing it through chambers around grates or stoves, or heating it in a furnace. In towns or manufacturing districts the air should be filtered before allowing it to enter the room. Thin flannel or muslin spread over the openings answers very well as filtering material. Outlets should be placed at the highest point of the room and should be protected from the weather. An opening into the chimney near the ceiling will answer well in many cases. In one-story buildings, ridge-ventilators make the best outlets. The entrance of snow and rain must be prevented by suitable ar- rangements. A small space or slit between the horizontal bars of the upper and lower window-sash will admit sufficient air in a proper direc- tion in small rooms, even when the window is shut. In all rooms, howsoever ventilated, doors and windows should be often opened to permit a thorough -flushing of the interior with fresh air. For large buildings, hospitals, schools, theatres, ships, and mines, two systems of artificial ventilation are in use. One operates by extracting the foul air by means of fans, the other by forcing in fresh air, allowing the impure air to find its way out as best it may. Eotating cowls on the tops of chimneys may be used to increase the aspirating power of the air; in this way the natural force of the wind may be utilized for ventilation of rooms or buildings of mod- erate size. Further details upon the practical application of these prin- ciples will be given in succeeding chapters of this work. QUESTIONS TO CHAPTER I. AIR. Wliat is the composition of the atmospheric air? Is the mixture a chemical or mechanical one? What constituent is the most constant in pro- portion, and what ones most variable? What are the causes and limits of variation in the composition of the air? Has this variation any effect upon health? How is the general uniformity of composition maintained? What is the relation of the oxygen and carbon dioxide to plant and animal life and to one another? What is the depth of the atmosphere? What is its weight, and how is this measured? How may you determine the altitude of any place above the sea -level? What effect has temperature on barometric pressure? What effect has moisture and why? Whence does the air derive its warmth? Where is the atmosphere warmest? What is the relation between the temperature and humidity of the air? "What is meant by "absolute" and "relative" humidity? How is each always designated? What is meant by "saturation"? What causes motion in air or wind? What conditions of the atmosphere probably have relation to, or influence upon, disease? Why should a sanitarian be a practical meteorologist? What are the physiological effects of diminution of atmospheric pressure ? What may aggravate these effects? To what are they due? Can the human body become accustomed to them? What name is given to this physiological disturbance? What diseases will probably improve in a rarefied atmosphere, and what ones will not? What are the effects of increased atmospheric pressure upon the organ- ism? Is there any danger of fatal results? Have the diurnal variations of pressure any effect upon the body in health or in disease? What effect has high temperature upon health? What diseases are more frequent in hot weather and in hot climates? What peculiar affection seems to be caused or favored by long-continued exposure to cold? What are some of the acute effects of cold? "What effect has the relative humidity in the production of these diseases? Indicate and explain a possible relationship of causation between coryza or influenza, bron- chitis and pneumonia. Is this altogether substantiated by statistics? Is Low temperature the only cause of pneumonia? What part has the relative humidity in the production of certain dis- eases ? "Wliat is the general rule as to the effect of winds or air-currents upon health? Name some apparent exceptions to this rule. Has the season any (43) 44 TEXT-BOOK OF HYGIENE. thing to do with, the morbidity and mortality from different diseases? Give examples. Wliat is the average proportion of carbon dioxide in the atmosphere? What should be the maximum limit permissible in dwellings? Is this limit often exceeded? When exceeded, to what are the evil effects upon health probably due? How much carbon dioxide alone may be present in the atmos- phere without producing any apparent ill effects? "\^Tien and Avhere in the out-door atmosphere is the proportion of carbon dioxide greatest? In what way may this be explained? T\liat are the products of respiration and perspiration, and which of these is most harmful to health? What evidence have we to that effect? Have we anj' evidence that the respiratory carbon dioxide alone is harmful to health? 'WTiere there is a moderate degree of respiratory pollution, what are some of the symptoms usually produced thereby? In the production of what especial disease has impure air a decidedly causative influence? WTiich is the more dangerous to health, carbon monoxide or carbon diox- ide? Of what gases is the former an ingiedient? How does it produce its harmful effects? Have sulphuretted and carburetted hydrogen any effect upon health? If so, in what proportions must they be in the atmosphere? Has ammonia, in the proportion in which it is usually found in the atmosphere, any bad effect upon health? ^Miat is sewer-air or sewei'-gas, and what are some of its constituents? In what way may it be the cause of infectious disease? Will the continued breathing of air polluted with sewer-gas affect health, and, if so, what symp- toms may be caused thereby? Is there any positive evidence that the emanations from cemeteries, bone- yards, etc., are harmful to health? "\Miat diseases may be produced by the inhalation of pathogenic micro- organisms carried by the air? How may the presence of ozone in the air be demonstrated? Upon what does the test depend? How might an approximate quantitative test of ozone be made? How may the suspended impurities in the atmosphere be collected for examination? Which method requires the least apparatus, etc.? How may the character and nature of the suspended particles be determined? How may a quantitative bacteriological examination be made? AMaat are some of the advantages of Dr. Dixon's apparatus? Of the sugar-filter method? How may pure cultures of micro-organisms in the air be obtained? How may the quantity of organic matter in the air be determined? Why do we determine the proportion of carbon dioxide in the air? What is Wol- pert's method for finding the percentage of this gas, and how may this method be simplified? Upon what does this test depend? "What precautions must be obseiwed in making the test ? What is the Angus Smith method for deter- mining the proportion of carbon dioxide? How may it be improved? What is the use of the phenolphthaleine in the solution? How is the percentage of carbon dioxide calculated? How is the alkaline solution to be prepared? Upon what does Pettenkofer's method depend? \"\Tiat apparatus and reagents are required? Why must the lime-water be standardized each time? QUESTIONS TO CHAPTER I. 45 What is the value of the oxalic-acid solution? What are some good indicators to use in this test? Why is just twice the volume of lime-water introduced into the bottle that is afterward taken from it and tested? What are some of the advantages and disadvantages of baryta-Avater in comparison with lime- water? How may the quantity of ammonia in the atmosphere be determined? How may the presence of other gases be shown? ViTiat is the usual test for carbon monoxide? Upon what is Vogel's test based? Is it a delicate one? Why is it usually not necessary to make a quantitative examination of the carbon monoxide? VentUation. — How much oxygen does an adult human being at rest ordi- narily take from the air, and how much carbon dioxide does he add to it in twenty-four hours? What percentage of carbon dioxide in the air indicates the greatest amount of organic impurity from respiration, etc., consistent with health? How much fresh air per hour is, therefore, needed by each individual to maintain this state of purity? Will sick persons need more fresh air than the well? Why? What is meant by ventilation? What should be excluded from the term? What matters must a proper system of ventilation consider? What gov- erns the amount of cubic space that can be allotted to each individual? What should be the minimum air-space for the well, and what for the sick? What should be the floor-space for each person, and why? From what kind of a source must the air for a ventilation supply be taken? What is the difference between natural and artificial ventilation? What are the forces acting to produce natural ventilation? What is meant by dif- fusion? Why is it insufficient for ventilating an occupied room? What is meant by perflation? Why cannot it be used alone for ventilation? Upon what does the inequality of atmospheric pressure depend? Why is it the most valuable of the forces of natural ventilation? In what part of an occupied room is the most impure air found, and why? What precautions must be observed in all plans for natural ventilation? What makes the air from a room pass up a chimney? When a room is heated by a hot-air furnace, how does the foul or used air escape? What rules may be laid down for the arrangement of a system of natural ventilation? Where should the fresh-air inlets of a room be located? How may the air be warmed before bringing it into the room? How should the inlet-tubes be arranged? Where should the outlets of a room be located? What systems of artificial ventilation may be employed for large build- ings or rooms ? By what appliances may we make use of winds for ventilating purposes? CHAPTER II. WATER. Physiologists teach that nearly two-thirds of the tissues of the animal body consist of water. Inasmuch as this water is constantly being lost by evaporation from the skin, exhalation by the lungs, and excretion through various organs, it is evident that the loss must be constantly supplied if the functions of life shall be properly per- formed. It appears probable that certain diseases are at times spread through the agency of insufficient or impure drinking-water. It is therefore a matter of very great importance to have a definite knowl- edge of what constitutes a pure and sufficient supply of water, and how best to secure it, to be able to detect its conditions of purity and impurity, and to know how to maintain the former and avoid the latter. It will be necessary to consider in detail, therefore, the quantity of water required by each individual for the maintenance of health, the sources whence water is obtained, how it should be col- lected and stored to the best advantage, the impurities likely to be con- tained in it, and the methods of keeping it pure, or of purifying it when it has become polluted or vitiated in any manner. THE QUANTITY OF WATER REQUIRED BY HUMAN BEINGS. Dr. Parkes, after a number of experiments, concluded that a man of the English middle class, "who may be taken as a fair type of a cleanly man belonging to a fairly cleanly household," uses about twelve gallons of water per day. This covers all the water needed, including a daily sponge bath. Dr. DeChaumont estimates^ that 16 gallons should be the daily allowance. By order of the British War Department, 15 gallons of water are allowed to each soldier daily. In very many instances this quantity cannot be furnished, but in such cases there necessarily results some deficiency in cleanliness. It is probable that among the poorer classes, especially where a large supply of water is not convenient, the quantity used is not over one- fourth of the above estimate. ^ Parkes' Hygiene, 6th ed., New York, vol. i, p. 5. (46) QUANTITY OF WATER REQUIRED. 47 head: Household Parkes and Kenwood^ give the average daily quantities per Table IV. Fluids as drink 0.33 Cooking 0.75 Personal ablution 5.00 to 10.00 Utensils and house washing 3.00 Clothes washing (laundry) 3.00 Water closets 5.00 Trade and manufacturing 5.00 Cleansing streets 5.00 Public baths and fountains 5.00 Flushing and cleansing sewers 5.00 Extinguishing fires 5.00 27.08 to 32.08 Municipal < In American cities the daily consumption is much greater, as seen from the following table: — Table V. Showing Consumption of Water in 105 American Cities. City and State Akron, Ohio p Altoona, Pa m Anderson, Ind m Atlantic City, N. J m Augusta, Georgia m Atlanta, Georgia m Battle Creek, Mich m Boston, Mass m Buffalo, N. Y m Burlington, Iowa p Binghamton, N. Y m Brocton, Mass m Camden, N. J m Cambridge, Mass m Cincinnati, Ohio m Chicago, 111 m Cleveland, Ohio m Charleston, S. C m Council Bluffs, Iowa p Denver, Colo p Detroit, Mich m Danville, 111 p Davenport, Iowa p Dayton, Ohio m Duluth, Minn m Danbury, Conn m Easton, Pa p D ily Per Population Consumjition Capita3 Gallons Gallons 46,733 '03) 7,500,000 137 52,000 '03) 4,500,000 90 20,178 '00) 2,000,000 66 32,272 '03) 5,250,000 138 41,283 '03) 5.500.000 110 96.550 '03) 7,500,000 60 18,563 '00) 1.133.000 60 594,618 '03) 83,000,000 145 381,403 '03) 125,000,000 320 23,201 '00) 2,000,000 80 39,647 '00) 50,000 '05) 2,000,000 36 79,811 '00) 12,000,000 160 98,444 '03) 8,775,000 89 340,000 '03) 48,536,000 137 1,873,880 '03) 175,000,000 200 444,600 '05) 61,572,000 138 55,807 '00) 3,070,000 55 25,802 '00) 2.500,000 85 147,111 '03) 32,000,000 200 369,805 '05) 60,212,5.39 108 16,354 '00) 2,500,000 157 37,768 '03) 4,000,000 100 92,716 '03) 7,000,000 66 57,397 '03) 5,000,000 85 16,537 '00) 2,000.000 125 23,238 '00) 2,000,000 87 ■Hygiene and Public Health, 1902. ' The per capita is based on the number of consumers. 48 TEXT-BOOK OF HYGIENE. Table V. — ( Continued. ) Showing Consumption of Water in 105 American Cities. City and State Elmira, N. Y p Erie, Pa m Evansville, Ind m Fort Smith, Ark p Fall River, Mass m Fond du Lac, Wis p Fort Wayne, Ind m Fitchburg, ]\Iass ni Grand Rapids, j\Iich m Harrisburg, Pa m Hartford, Conn m Haverhill, Mass m Henderson, Ky m Houston, Texas p Holyoke, Mass m Indianapolis, Ind p Johnstown, Pa. . . p Jamestown, N. Y p Kansas City, Mo m Kingston, N. Y m Lowell, Mass m Los Angeles, Cal m Lynn, Mass m Louisville, Ky m Lincoln, Neb m Manchester, N. Y m McKeesport, Pa m Minneapolis, Minn m Milwaukee, Wis m Memphis, Tenn p ]\Iuskegon, Mich m Norfolk, Va m New Bedford, Mass m New Orleans, La p New Albany. Ind. p Nashville, Tenn m New Haven, Conn p Oshkosh, Wis p Paterson, N. J p Peoria, 111 m Pittsburg, Kans p Portland, Me p Portland, Ore m Quincy, Mass m Quincy, 111 p Reading, Pa m Rochester, N. Y m Roanoke, Va p Rock Island, 111 m Rushville, Ind m Richmond, Va m Salem, Mass m Saginaw, Mich m 1 Daily Per Population | Consumption Capita Gallons Gallons 37,106 ('03) 5,000,000 125 56,363 ('03) 10,000.000 168 61.482 ('03) 9.000.000 145 11,587 COO) 2,225,000 125 114,004 ('03) 4,000.000 36 20,000 ('05) 1.250.000 63 48,031 ('03) 4.000.000 84 34.378 ('03) 3.000,000 90 93,679 ('03) 14.000.000 139 52,951 ('03) 8,750,000 135 100,000 ('05) 6,150.000 67 38,987 ('03) 4,100,000 111 10,272 75,000 COO) ('03) 10.000.000 134 50,831 ('05) 5,000,000 100 197,555 ('03 ) 18,750,000 94 39,980 ('03 ) 8,000.000 200 22,892 COO) 2,250,000 100 250,000 ('05) 19,200.000 77 25,516 ('03) 3,500,000 200 100,150 ('03) 5,500,000 52 116,420 72,350 ('03) ('03 ) 165 5.500,000 64 215,722 ('03) 18.000,000 72 44,158 ('03) 18,000,000 36 60,845 ('03) 3.500,000 50 38,274 ('03) 4,200.000 90 214,112 ('03) 18.500,000 79 313.025 ('03) 27.000,000 80 113,669 ('03) 12.000.000 100 20,818 COO) 2,900,000 132 55.318 ('03) 6,300,000 110 66,000 ('05 ) 7,000,000 95 300,625 ('03 ) 14.000.000 47 20,628 COO) 2.000.000 66 83,275 ('03) 13,500.006 135 114.627 COO) 20.000.000 150 29.919 ('03) 2,500,000 85 113.217 ('03) 10,500,000 100 02,348 ('03) 4.500,000 72 10,112 COO) 1.000,000 75% 52,656 ('03) 6.000.000 110 98,655 ('03) 20,000,000 200 26,053 ('03) 2,600.000 103 37,680 ('03 ) 1.435,000 38 85.051 ('03) 11,000,000 124 170,798 ('03) 15,238,000 87 21,495 COO) 3,000.000 94 19.493 COO) 3,400,000 17 • 4,541 COO) 800.000 160 86.148 ('03 ) 13,000,000 129 23,504 ('03) 3,300,000 89 45,543 ('04) 10,000,000 200 QUANTITY OF WATER REQUIRED. 49 Table V. — (Continued.) Showing Consumption of Water in 105 American Cities. City and State Sioux City, Iowa . . •. m Salt Lake City, Utah m South Bend, Ind m St. Joseph, Mo p Somerville, Mass m Springfield, Mass m St. Paul, Minn m St. Louis, Mo m Springfield, III m Syracuse, N. Y m San Antonio, Texas p Taunton, Mass m Terre Haute, Ind p Toledo, Ohio m Utica, N. Y p Waterbury, Conn m Vincennes, Ind p Watertown, N. Y m Worcester, Mass m Wilmington, N. C p Waltham, Mass m Washington, D. C m Wilmington, Del m York, Pa p Yonkers, N. Y m Daily Per Population Consumption Capita Gallons Gallons 33,111 COO) 1,290,000 39 57,138 ('03) 15,000.000 200 40,327 ('03) 4,000,000 81 110,479 ('03) 6,000,000 55 68,090 ('03) 6,000,000 89 74,916 ('05) 9,700,000 128 172,038 ('03) 9,000,000 52 612,279 ('03) 75,000.000 125 36,211 ('03) 4,470,000 108 114,443 ('03) 12,000.000 105 58,016 ('03) 10,000,000 170 32,713 ('03) 1,750,000 64 54,008 ('05) 4,200,000 77 145,901 ('03) 11,000,000 69 60,097 ('03) 4,000,000 33 56,521 ('05) 6,000,000 130 10,249 ('00) 21,696 COO) 4,000,000 188 130,207 ('05 ) 10,000,000 75 20,976 COO) 700,000 50 23,481 COO) 2,000.000 80 300,000 ('05 ) 65,000,000 217 84.000 ('05 ) 8,000.000 95 36,438 ('03 ) 2,850,000 70 62,000 ('05 ) 6,500,000 92 "m" — Municipal, "p" — Private Company. This excessive consumption is brought about not so much by legitimate use of the water as by waste : negligence and imperfections in the supply apparatus, allowing the water to run in the winter to prevent freezing of pipes, etc. When it is taken into consideration that the cost of pumping water averages from four to five dollars per million gallons, and in cities which purify their water-supply the cost is from two to three dollars more, the question of waste assumes a very important economic phase. In several of the larger American cities this problem has been satisfactorily solved by the introduction of metres, by means of Avhich the water consumed in each household or factory is measured and charges regulated according to the amount of water consumed. In Wilmington, Del., the introduction of metres has eliminated waste and reduced the consumption to an average of 100 gallons per capita. This, however, includes the consumption of water by manufactories. In one of the strictly residential portions of the city the per capita consumption averages 30 to 35 gallons daily, the latter being the average amount of water required by a middle- class American household. One of the objections to metres is that the 50 TEXT-BOOK OF HYGIENE. very class of persons whom it is desired to induce to use a plentiful supply of water would, from motives of economy, use less than is necessary for cleanliness and health. This objection, however, -is purely hypothetical. Water is the cheapest commodity, and by the elimination of waste the cost could be still further reduced. As a matter of fact, it is not abundance of water that encourages cleanli- ness. "You can lead a horse to the water, but you can't make him drink it." Habits of cleanliness should be inculcated in ways other than by allowing a wanton waste of water. SOURCES OF DRINKING=WATER. All water, from whatever direct source obtained, comes origin- ally, by precipitation, from the atmosphere. In many places the rain- or snow- water is the only source of supply. This is usually collected as it falls upon the roofs of buildings and conveyed by gutters and pipes to cisterns, where it is stored until needed. In Venice, the rain falling upon the streets and courtyards is also collected in cisterns after filtering through sand. The cisterns used for the storage of water in ISTew Orleans and other Southern cities in the United States, where the temperature rarely falls below the freezing-point, are generally constructed of wood and placed above-ground. Farther north, where it is necessary to protect them against the action of frost, they are placed under-ground. These under-ground cisterns are usually built of brick. The water from cisterns above-ground becomes very much heated in summer, and necessitates the use of large quantities of ice to make it palatable. The water from the under-ground cisterns is pleasantly cool in sum- mer, and is also guarded against freezing in winter. There are, however, very serious objections to storing drinking-water in under- ground cisterns. These reservoirs are usually placed within a few feet of privies and cess-pools, and, as neither the retaining walls of the cisterns nor those of the privies are water-tight, it often happens that the drinking-water becomes strongly impregnated with the sol- uble portions of the excrement, or the products of its decomposition, which have drained into the cistern. Personal observations in Mem- phis in 1879, as well as the careful chemical analyses made afterward by Dr. Chas. Smart, U. S. A.,* have convinced the author that the objections to all under-ground cisterns built of brick, stone, or cement are insuperable from a sanitary point of view. Dr. Smart ■Report National Board of Health, 1880, pp. 437-441. SOURCES OF DUmKlNa-WATER. 51 found over one-half of the under-ground cisterns examined by him in Memphis and other cities and towns to be leaky and presenting evidence of organic pollution. The water from 31 out of 80 cisterns analyzed showed decided contamination by sewage. It would seem advisable to prohibit all under-ground cisterns for the storage of drinking-water unless they are constructed of iron, which should be protected against oxidation by a thorough coating of coal-tar. Where any other system of collection and storage is available, how- ever, the under-ground cistern should be unreservedly condemned. Eain-water collected in the country, away from manufacturing districts, is usually quite pure and wholesome. Its taste is, however, flat and insipid, owing to absence of carbon dioxide and mineral con- stituents. In cities rain-water frequently contains such a large amount of organic matter and other impurities, which have been washed out of the air by the rain, that it may be unfit for drinking. On account of its softness, rain-water is very desirable for washing and other domestic purposes. If the statement made in the last chap- ter, concerning the presence of organisms in the atmosphere, is remem- bered, then it will be evident on a moment's thought that such organ- isms, when contained in rain-water, may be the source of disease. The putrefaction which so readily takes place in rain-water upon standing a few days is caused by certain of the organisms carried down out of the lower strata of the air by the descending rain or snow. Precipitation is an exceedingly untrustworthy source of water, and should never be depended upon when other sources of supply are available. Water famines are frequent wherever people are com- pelled to rely upon such an uncertain source of supply as rain or snow. Elvers and smaller streams probably supply the larger number of cities and towns in this country with drinking-water. When care is taken to prevent the pollution of the stream above the point whence the water is taken, this is usually of fair quality for domestic pur- poses. When the river can be tapped near its source, or before a large number of manufacturing establishments can empty their waste products into its current, or before it receives the sewage of a consid- erable number of inhabitants living on its banks, the water can gen- erally be regarded as safe. It is very difficult, however, except in the less settled portions of the country, to find these favorable conditions. Among the minor ol)iections to the use of river-water for domes- tic purposes are the liability of most streams to become turbid in times of freshet, and the discoloration of the water from dissolved coloring-matters if tlie stream flows through a marshy or peaty 52 ' TEXT-BOOK OF HYGIENE. region. These objections are, however, not serious, as filtration will readily remove the suspended matters. The coloring-matter is prob- ably harmless. The organic matter contained in the water of some streams, even when pollution by sewage and manufacturing refuse is absolutely excluded, may, however, be the cause of disease. Dr. Smart has shown^ that the water from streams in Nebraska, Wyom- ing, and Utah contained organic matter varying in amount from .16 to .28 parts per million.'' He thinks the so-called "mountain fever" of the Eocky Moimtain region is a malarial fever caused by the large amount of organic matter in the drinking-water. Dr. G. M. Kober, U. S. A., states that he has frequently drunk water from mountain streams which had a perceptible taste of cattle- manure, and suggests that as the origin of the ammonia found by Dr. Smart in the water of mountain streams. Dr. Kober also regards the "mountain fever" as a typhoid fever with malarial complications.' The most serious objection to the use of river-water for domestic purposes is the emplo}mient of streams as carriers of refuse from manufacturing establishments, or of the sewage of cities and towns. In Great Britain and some parts of the continent of Europe, owing to the density of population and the variety and extent of manufac- turing industries, many of the streams are in an extremely filthy condition. In this country, too, especially in the more thickly settled manufacturing districts, the pollution of rivers has increased to a degree to seriously jeopardize the health of the people who are com- pelled to draw their water-supply from such streams. That the pres- ence of such excessive contamination renders the water unsuitable for domestic purposes must appear evident. It is probable, however, that the most dangerous of the polluting matters are the excreta of human beings, especially those of patients suffering from certain specific dis- eases, such as typhoid fever or cholera. Only a few years ago it was a generally-accepted theory that running water, though polluted by sewage, "purifies itself" after fiow- ing a distance of twelve miles, and the comforting and reassuring doc- trine is still held by many. Recent observations point to the con- clusion, however, that "no river is long enough to purify itself." A certain proportion of the sewage, it is true, undergoes oxidation in the presence of light and air and minute organisms,® and so becomes ^American Journal Med. Sciences, January, 1878, p. 28 et seq. •^ The source of this organic matter seems to be the melted snow which makes up a large portion of the streams. 'Report of California State Board of Health for 1886, pp. 48 and 177. ' Desinfection, in Eulenburg's Realencyclopsedia d. ges. Heilkunde, vol. iv, p. 68. SOURCES OF DEINKING-WATER. 53 changed into other, possibly innocuous, compounds. But at present it is not known what proportion or what kind of organic matter does undergo this change. Another portion of the impurities is deposited upon the bottom and sides of the stream, having been only held in suspension, and not dissolved in the water. A portion probably forms chemical combinations with other suspended or dissolved matters, and is changed into compounds which may be volatile and pass off into the air or form insoluble precipitates. The remainder is rendered less perceptible or imperceptible by dilution. Every stream has sources of inflowing water — feeders — which increase its volume, and thus dilute any foreign admixture. In view of these facts, the theory of the self-purification of streams, as formerly held, can no longer be regarded as true. But it is unquestionably true that running water does regain comparative purity if the inflow of sewage and other refuse is not excessive. It cannot be stated with confidence, however, when a stream, once pol- luted, becomes fit to use again. The water from fresh-water lakes aiid ponds is generar.y to be preferred to river-water for domestic use. It is less liable to become turbid from time to time, and, except in the case of small ponds, the inflow of sewage is not likely to cause fouling of the water to any serious extent. When the supply can be drawn from large lakes, as is done in Chicago and other cities on the great lakes of the United States, no purer or better source can be desired. In these cases the point whence the water is taken should be far enough from shore to avoid the possibility of sewage contamination. When the water- supply is taken from small ponds, all sewage and waste products from houses and factories must be rigidly excluded; otherwise, diseases attributable to the polluted water are likely to arise among those using the same. The water in small lakes and storage reservoirs sometimes be- comes offensive in taste and odor. The water-supplies of several of the large Eastern cities have at times had a peculiar odor and taste somewhat resembling cucumbers. The cause of this odor and taste was found to be a minute fresh-water sponge, the Spongilla fluviatilis. A still more offensive odor, tersely described as the "pig-pen odor," is given to the water by the decay of certain species of nostoc and other algffi. It is not known that either these vegetable or animal micro- organisms, if present, render the water prejudicial to health. Ponds are often used as sources of ice-supply. It was formerly supposed that in the process of freezing, solid matters in the water 54 TEXT-BOOK OF HYGIENE. were not included in the block of ice when congealation occurred. Eecent observations have shown the falsity of this assumption. In 1875, an outbreak of acute intestinal disease at Eye Beach, ISTew Hampshire, led to an inquiry by Dr. A. H. Nichols, which disclosed the fact that the ice used contained a large percentage of organic matter.^ The use of ice from a different source was followed by an almost immediate disappearance of the disease. Upon further inves- tigation it was discovered that the impure ice had been gathered from a small, stagnant pond into which a small brook carried large quantities of saw-dust from several saw-mills. The water of the pond was loaded with organic matter, and in summer the gases of decay arising from it were very offensive. Chemical examination showed that the ice from this pond contained nearly 6 quarts of organic matter in 100,000, while in pure ice the organic matter amounted to only .3 part in 100,000. A similar investigation into the character of the ice furnished to the residents of Newport, E. I., was made under the auspices of the Sanitary Protection Association of that city. The ice, which was cut from ponds in the immediate neighborhood of the city, was found to contain an excessive proportion of organic matter. Large quantities of sewage and other impurities were discharged into these ponds. Experiments made at various times show that the purification of water by freezing is in no sense absolute. A considerable num- ber of the bacteria, infusoria, and other organisms remain in the ice and retain their vitality, so that when thawed they rapidly multiply. In the ordinary process of freezing the upper portion is the purest, but if snow or rain fall upon the ice and freeze, this upper layer will be found much more impure than the lower. Eational conclu- sions from these experiments are, that ice should not be gathered from an impure source, and that an early harvest of the ice should be encouraged. Prudden has sho^^^l that typhoid bacilli contained in water are not entirely destroyed by freezing, even after remaining in this con- dition for 103 days. Springs and wells supply the water for most persons not aggre- gated in large communities, as cities and towns. Even in the latter no inconsiderable quantity of the water used for drinking and domes- tic purposes is derived from wells. Spring-water usually comes from a source at a considerable depth below the surface; that is to say, the 'Report Massachusetts State Board of Health, 1876, p. 467. SOURCES OF DRINKING-WATER. 55 water has percolated through thick strata of soil before re-appearing at the surface. In its passage through the soil it has lost most of its organic matter, and perhaps taken up mineral and gaseous con- stituents in larger quantities. It may be so strongly impregnated with the latter as to vitiate it for ordinary use and to render it val- uable as a medicine. Ordinarily, however, spring-water is clear, cool, and sparkling, with a refreshing taste and uniform temperature, and is in all respects an agreeable and wholesome beverage. Springs vary greatly in character. They may be cold, hot, or thermal, and boiling or geysers; they may be either superficial or deep, and the water may be either pure or polluted, depending on Fig. 3.— Showing Formation of Spring. E, Earth. R, Rock. W8, Water-bearing Stratum. IB, Impervious Stratum. *S', Spring. source or location. The chemical constituents of spring-waters in this country vary from waters containing but a few grains of mineral substances to the gallon to waters so saturated with mineral matter as to be classed as medicinal. The various mineral waters in this country are classified by Hay- wood and Smith^° as follows : — Group. Thermal Nonthermal Class. I. Alkaline II. Alkaline- saline TIL Saline IV. Acid Table VI. Subclass {Carbonated or bicarbonated Borated Silicated (Sulphated Muriated Nitrated r Sulphated I Muriated I Nitrated < Sulphated / Muriated Sodic 1 Lithic Potassic ' Calcic Magnesic Ferruginous Alumnic Arsenic kBromic llodic /Silicous Boric I Nongaseous Carbondioxated Sulphuretted Azotized Carburetted I Oxygenated '"Bureau of Chemistry, Bui., 91, 56 TEXT-BOOK OF HYGIENE. Under this classification the mineral waters on the market may be arranged as follows : — Alkaline Bicarhonated Sodic. — Augusta White lithia water. Gey- ser Jefi^ress lithia water. JManitou water. Powhatan water. Thomp- son's bromin and arsenic water. Alkaline Bicarhonated Magnesic. — Osceola water. Alkaline Bicarhonated Calcic. — Allouez water. Augusta White lithia water. Bear lithia water. Crocket arsenic lithia water. Gol- indo lithia water. Great Bear water. Jeffress lithia water. London- derry lithia water. Manitou water. Mardela water. Massanetta water. Missisquoi. Osceola water. Otterburn water. Poland water. Powhatan M^ater. Eubino Healing Springs water. Sublett lithia water. Yitan water. Alkaline Bicarhonated Ferruginous. — Mardela water. Alkaline-saline Muriated Sodic. — Carlsbad water. Champion water. Chief water. Congress water. Hathorn water. High Eock water. Lincoln water. Magnetic water. Peerless water. Gitche Crystal Spring water. Seltzer water. Sheboygan water. Vichy water. White Eock lithia water. Alkaline-saline Muriated Potassic. — Gitche Crystal Spring water. Alkaline-saline Muriated Calcic. — Carlsbad water. Champion water. Chief water. High Eock water. Lincoln water. Magnetic water. Peerless water. Seltzer water. White Eock lithia water. Sheboygan water. Saline Sulphated Sodic. — Pluto concentrated water. Saline SulpJiated Magnesic. — Veronica water. Saline Sulphated Calcic. — Berry Hill d^^spepsia water. Bedford mineral water. Buffalo lithia water. Geneva lithia water. Tate epsom water. Saline Muriated Sodic. — Arondack water. Blue Lick water. Cherrydale water. Deep Eock water. Mount Clemens water. Star water. A^ictoria Avater. Webster Springs salt sulphur water. Saline Muriated Calcic. — Cherrydale water. Add Sulphated Aluminic. — Eockbridge alum water. Walla- whatoola water. Eegarding the effect of mineral waters on the human organism both in health and disease, Haywood and Smith^^ present the follow- ing summary: — Carhonated or Bicarhonated Alkaline Waters. — Stimulate the se- cretions of the digestive tract, neutralize hyperacidity of the stomach, ^Loc cit. SOURCES OF DRIXKIXG-WATER. 57 increase metabolism, dissolve uric acid and uric acid deposits, increase the flow of urine, and correct acidity of the latter. They are, there- fore, of value in catarrhal conditions of the mucous membranes, rheu- matism, gout, diabetes, etc. 8odic Carbonated and Bicarhonated AlJcaline Waters. — Increase metabolism, dissolve uric acid, and allay irritation of the mucous membrane of the urinary tract. They are useful in acid dyspepsia, rheumatism, gout, and diabetes. Potassic Carbonated and Bicarhonated AlJcaline Waters. — Have very much the same action as the sodic carbonated. Their chief use is in the treatment of calculi. Lithic Carbonated and Bicarbonated All-aline Waters. — These are active diuretics and form solul^le urates. They are used in the treat- ment of rheumatism, rheumatic tendencies, and gout. In cases of gravel and calculi they are a^so valuable disintegrating agents. Magnesic Carbonated and Bicarbonated All-aline Waters. — Act as mild laxatives, and are perhaps the best of all the alkaline waters in correcting an acid condition of the stomach and curing sick headache caused by constipation. They favor the solution of uric acid, are val- uable agents in breaking up deposits in the bladder, and are much used in catarrhal conditions of the mucous membrane or the urinary organs. Calcic Carbonated and Bicarbonated Alhaline Waters. — This class of waters produces constipation and decreases the secretions. Very obstinate cases of chronic diarrhea have been cured by a sojourn at a spring rich in calcium bicarbonate. Uric acid gravel and calculi are also disintegrated and eliminated by the free use of these waters. Ferruginous Bicarbonated All-aline Waters. — Increase the amount of hemoglobin and in connection therewith increase the temperature, pulse, and weight. They also increase the appetite and reduce intes- tinal activity. They give excellent results as a tonic, and find their principal application in anemia and general debility. Prolonged use results in constipation and derangement of the digestion. B orated Alhaline Waters. — They act as antacids. They promote the menstrual flow and may be used in catamenial irregularities. Muriated AlMUne-saline Waters. — They increase the flow of urine and the excretion of uric acid. Are especially valuable in the treatment of catarrhal conditions of the mucous membrane of the stomach, intestines, biliary passages, and urinary tract. Sulphated All-aline-saline Waters. — They act as diuretics. In large quantities they act as purgatives by increasing the peristaltic movement and liquefying the intestinal contents. Valuable in the 58 TEXT-BOOK OF HYGIENE. treatment of catarrhal conditions of the mucous membrane and in obesity. Muriated Saline Waters. — Stimulate the secretion of the stom- ach, increase digestion, favor a better absorption of foods, and act as diuretics. Sodic Muriated Saline Waters. — Increase the flow of gastric juice, improve the appetite, increase the flow of urine and excretion of urea. Also prevent putrefactive changes in the intestines. Potassic Muriated Saline Waters. — Action very much like that of sodium salt. Lithic Muriated Saline Waters. — Same as above, with an intensi- fied diuretic action due to the lithium. Calcic Muriated Saline Waters. — Act as a tonic, increase the flow of urine, sweat and bile, and are used in scrofula and eczema. Sulphated Saline Waters. — These waters are laxative or purga- tive, according to the amount taken. Are indicated where long-con- tinued intestinal stimulation is desired without stimulation of the vascular system. Sodic and Magnesic Sidpliated Saline Waters. — Act as laxatives in small, and purgatives in large, doses. Increase flow of intestinal fluids and urine, also excretion of urea. Are of great service in elim- inating syphilitic, scrofulous, and malarial poisons from the system, in throwing off mercury and other poisons. Useful in the treatment of obesity, derangement of the liver, and Bright's disease. Potassic Sulphated Saline Waters. — Same effect as above. Calcic Sulphated Saline Waters. — Have no well-known action. Ferruginous Sulphated Saline Waters and Ahuninic Sidphated Saline Waters. — Iron and aluminum usually occur together when either is present as a predominating constituent in sulphated saline waters. These are practically always acid and their action is best considered under the sulphated acid group. Nitrated Saline Waters. — Only one spring of this kind found. Action has not been determined. Acid Waters. — Principally composed of the ferruginous-aluminic sulphated classes, although there are a few acid springs which contain comparatively little iron and aluminum, but quite large amounts of calcium, sodium, or magnesium. These waters are used in relaxed conditions of the mucous membranes, especially in diarrhea and dysen- tery. They are also used in the treatment of exhausting night-sweats and impoverished condition of the body brought about by intemper- ance or specific diseases. Locally, they are used in the treatment SOURCES OF DRINKING-WATER. 59 of inflamed or relaxed conditions of the mucous membrane such as are found in conjunctivitis, chronic vaginitis, etc. Have the usual effect of all iron waters, but when desired as a tonic it is best to give the ferruginous carbonated water, as the latter is more readily ab- sorbed and assimilated. Iodic and Bromic Waters. — Act as alteratives. Stimulate the lymphatic system to greater activity and promote absorption in all tissues. Indicated in the treatment of scrofula, syphilis, goitre, chronic exudations, etc. Also favor the elimination of mercury and other metallic poisons. The bromic waters also act as sedatives. Arsenic Waters. — Act as alteratives, increase the appetite and digestion, and improve the general nutrition of the body by increas- ing the secretions of the gastro-intestinal mucous membrane and at the same time checking katabolism. Especially valuable in the treat- ment of anemia and a number of skin diseases. Also indicated in chronic malaria, neuralgia of anemic origin, scrofula, etc. Silicious Waters. — Precise action unknown. Have been said to be useful in cancer and to have caused the disappearance of albumin and sugar from the urine. Azotized and Oxygenated Wateis. — On account of slight solu- bility neither nitrogen nor oxygen occurs in waters in very large quantities. They possess no medicinal value. Carhondioxated Waters. — Increase the flow of saliva and intes- tinal fluids, also increase the peristaltic movement of the stomach and thereby improve digestion. Also tend to increase the flow of urine. Obstinate cases of nausea are often relieved by these waters. Carhuretted Waters. — Sometimes occur in coal and natural gas regions. Are not known to have any medicinal value, but are usually considered unfit for drinking purposes. Sulphuretted Waters. — Increase the action of the skin, intestines, and kidneys. Also possess a decided alterative effect. Have been used in the treatment of syphilis, chronic metallic poisoning, rheu- matism, and 'gout. They have also given excellent results in many skin diseases, hyperhemia of the liver, and in catarrhal conditions of the pharjTix, lar^mx, and bronchi. The great demand for spring-waters, especially mineral waters, has called forth a supply of all kinds of spring-waters, good, bad, and iufliffercnt. In many cases the claims made by the promotors are so extravagant as to class the water among the rankest of patent medi- cines. The United States Bureau of Chemistry, therefore, has done a most valuable service to the people and the medical profession by 60 TEXT-BOOK OF HYGIENE. analj'zing the more popular mineral waters. The following table shows the results of some of these analyses, compiled from Bulletin No. 91:— Table VII. Showing Analyses of Some of the 3Iore Popular Mineral Waters. =i a o a a .1 1 2 S ■a _o 3 -S o 2 J3 '3 o a a < < ^ 2 3 o .d tH '0 o M a 3 2 'S c a 3 a 3 a s 3 O .3 a o a _3 3 a a, 3 a CD o o X a is c3 3 cs •5 U a O T3 c -a U4 ■< 'A 2 o < M P-, IB Ph CO Part-^ per Million. ,008 .051 1.33 .001 .45 0.24 (a) 4.6 46 5.3 (Calcic Bicarb. Alkaline) 08 3.05 392.8 .25 .24 169.5 3,170 (a) 802.7 14 151 4 (Magoesic Sulphated Sal.) Bedford Mineral Water . . (Calcic Suiphated Saline) ,014 .008 .05 Tr. .85 .015 Tr. 9.3 9.2 29 686.1 Geneva Lithia Water . . . (Calcic Suiphated Saline) .015 .015 .10 Tr. .55 .048 .6 7.6 330.4 Tr. 2.8 575 3 Buffalo Lithia Water (Calcic Suiphated Saline) .035 .50 Tr. .60 .114 Tr. 76 12 77.7 31.7 Vitau Table Water (Cal ic Bicarb. Alk.) .05 .20 .45 (a) 10 5 Tr. 14.9 .01 .04 20 Tr. .30 03 Tr. 32 17 5 11 (Calcic Bicarb. Alk.) Londonderry Lithia Water (Calcic Bicarb. Alk.) .015 .075 .66 Tr. .90 .048 Tr. 5.5 .5 11.2 White Rock Lithia Water . .04 .09 1 .005 .50 .125 76.4 5.7 573.6 49.6 Bear Lithia Water . . . (Calcic Bicarb. Alk.) .02 .04 .2 Tr, .25 .063 Tr. 3 1 12 Tr. 4.3 Massanetta Water . . . (Calcic Bicarb, Alk.) .175 .054 ' .5 .001 .45 .549 (a) 2.9 Otterburn Lithia Water . (Calcic Bicarb Alk. ) .065 .027 Tr. 001 .70 207 .28 .3.6 43 41 Tr., Trace; (a). Heavy Trace. SOURCES OF DRINKING-WATER. 61 The above table shows how several of the high-priced and much- vaunted lithia waters are such only in name, while some of the sup- posedly pure spring-waters are no better than water from. an average farm-spring. The character of well-water is often justly open to grave suspicion. Being derived from those strata of the soil which are most likely to be contaminated by the products of animal and vegetable decompo- sitions, the unwholesomeness of the water is inversely proportional to the degree of saturation of the soil with the products of decay. It has been found by experiment that, when organic matter largely diluted with water is allowed to percolate through soil, it undergoes a gradual decomposition in the presence of certain minute organisms, nitrates and nitrites being formed at the expense of the ammonia and other organic combinations. If, however, the soil is saturated with organic matter in excess, and in a state of concentration, putre- faction takes place, and the conversion of the organic matter into nitrates and nitrites is retarded. Deep or Artesian Wells. — The name artesian is derived from the province of Artois, France, where these wells were simk centuries ago. They are formed when a boring taps a water-bearing stratum con- fined between two impervious geological formations. This water- bearing stratum forms a subterranean reservoir which is fed by the percolation of the surface at some point where the upper impervious stratum is either fissured or absent. This is known as the catchment area. This area may be near or far from the point where the well is sunk and it may be subject to pollution, and there is, therefore, no absolute assurance that because a well is deep the water is always pure. Sedgwick and Prescot found the following numbers of bac- teria in a series of deep wells in Massachusetts : — ■ Table VIII. Depth of Well Number of Bacteria Fer in feet. Cubic Centimetre. 100 • 30 193 269-254 213 101-106 254 150-135 377 48-54 454 205-214 Pfuhl, a well-known German authority, cites an instance of pol- lution passing through 180 feet of gravel. The chief objection to 62 TEXT-BOOK OF HYGIENE. artesian wells is their high contents in mineral substances, which im- part to the water a permanent hardness. In some regions the amount of iron is so great as to act destructively on tlie pipes. Thus, in the town of Gloucester, N". J., the artesian wells which supplied that town with water had to be abandoned, owing to the excess of iron in the water. The following analyses of the water from the four artesian wells in Gloucester were made by Messrs. Hamlin and Morrison: — Table IX. Parts Per Million. Well Number 12 3 4 Calcium carbonate 45 21 00 00 Magnesium carbonate 23 19 17 12 Calcium sulphate 51 49 65 73 Sodium chlorid 9 11 18 16 Iron oxid and aluminum 14 11 22 62 Matter insoluble in acid 00 00 32 30 Volatile and inorganic matter 28 6 76 30 Nitrates 00 00 00 00 Nitrites 00 00 00 00 Iron 9 7 9 14 Total solids 172 117 220 223 The quantity of water to be obtained from artesian wells is very uncertain, depending, as it does, on the extent of the catchment area, the rainfall, and the number of taps along the subterranean water- course. In some localities it may be impossible to obtain an artesian supply, and again the supply may be large at first and gradually diminish. Drinking-water is sometimes procured by melting snow or ice. It is not probable that water derived from these sources is unwhole- some, although there is strong popular prejudice against it. Ice and snow may, however, contain large amounts of impurities, as already referred to, and be for this reason unfit for use. The following qualities are desirable in water for drinking and domestic purposes : — 1. The water should be colorless, transparent, sufficiently aerated, of uniform temperature throughout the year, and without odor or de- cided taste. 2. The mineral constituents (magnesium and lime salts) should IMPURITIES IN WATER. 63 not be present in greater proportion than 4 or 6 parts per 100,000. More than this gives to water that quality known as "hardness." 3. There should be but little organic matter present, and no liv- ing or dead animal or vegetable organisms. 4. The water should be almost free from ammonia and nitrous acid, and should contain but very small quantities of nitrates, chlor- ides, and sulphates. 5. It should contain less than one milligramme of lead per litre. A larger proportion than this is likely to be followed by lead poisoning. 6. It should contain no pathogenic bacteria and but few water bacteria. IMPURITIES IN WATER. The transparency and the color of water are affected by the presence of suspended or dissolved mineral or organic matters. If, after standing for a time, the water deposits a sediment, this is de- pendent upon insoluble matters. If the sediment turns black when heated in a porcelain capsule over an alcohol or gas flame it contains organic matter. If the sediment or residue effervesces upon the ad- dition of hydrochloric acid the presence of carbonates is indicated. Water may be colored by metallic salts or by vegetable matter. It may also contain large quantities of mineral or organic matter, or even living organisms, without especially diminishing its transparency. For example, the ova of tape-worms may exist in water in considerable numbers and yet remain perfectly invisible except under the micro- scope. The presence of sulphur compounds, or of various vegetable and animal organisms (sponges, algae, etc.), may give to water an un- pleasant odor and taste. In the oil regions of this country most of the drinking-water is contaminated with petroleum, which is very disagreeable to one unaccustomed to it. It is not probable that the small quantities of the oil imbibed with the water have any deleterious influence upon the organism. Many works on hygiene fix a limit to the amount of solid matter allowable in drinking-water. The International Congress of Hygiene, at Brussels, fixed the limit at 50 parts in 100,000. It is impossible, however, to say of any particular specimen of water that its content of solid matter, whether organic or mineral, will be prejudicial to health, without trial. At the same time it is prudent to reject all waters containing a considerable proportion of solid organic matter, 64 TEXT-BOOK OF HYGIENE. as determined by the degree of blackening on heating the sediment or residue after evaporation, or by determination of nitrogen. The hardness of water is due to the presence of earthy carbonates, or sulphates, or both. If the hardness is due to carbonates it is dissi- pated by heat, as in boiling the water; the carbon dioxide is driven off, and the base (calcium or magnesium oxide) is precipitated upon the bottom and sides of the vessel. This is termed "temporary hard- ness." The hardness due to the presence of earthy sulphates is not removed upon heating the water, and is termed the "permanent hard- ness." The hardness depending upon both the carbonates and sul- phates is called the "total hardness." The proportion of the above-mentioned earthy salts present in a given specimen of water is determined by what is called the soap test. ' This test depends upon the property which lime and magnesia salts possess of decomposing soap (oleate and stearate of soda). The quantity of a solution of soap of a definite composition decomposed by a quantity of hard water indicates the amount of the salts present. DISEASES DUE TO IMPURE DRINKING=WATER. Hard water is popularly believed to be the cause of calculous dis- eases and of goitre and cretinism, but no reliable observations are on record showing that the belief is founded upon fact. At the same time it is undoubtedly true that calcareous waters produce gastric and intestinal derangements in those unaccustomed to their use. Large amounts of suspended mineral matter are frequently pres- ent in river-water, and may give rise to derangements of the digestive organs. If there is carbonate of lime present, the water can be easily clarified by the addition of a small quantity of alum. Sulphate of lime and a bulky precipitate of hydrate of alumina are formed, whicli carry the suspended matters to the bottom. About 10 centigrammes of crystallized alum are sufficient to clarify a litre of water. This amount of alum is too small to affect the taste of the water percept- ibly. This method is frequently used to clarify and render fit for use the water of the ]\Iississippi Eiver, which is usually very muddy. Lately, the city of St. Louis, which derives its water-supply from the Mississippi Eiver, has been using ferrous sulphate and lime as a coagulant, instead of alum. The action of either of these coagulants is to conglomerate the fine particles of clay and thus facilitate their sedimentation. At the same time these coagulated solid particles carry with them the bacteria, and a purification of 90 to 98 per cent, results. DISEASES DUE TO IMPURE DRINKING-WATER. 65 Although the opinion is widespread that water containing much mineral matter, either in solution or in suspension, is deleterious to health, there is very little evidence absoliitely trustworthy upon this point. The presence of large quantities of organic matter in water, whether these matters be of animal or vegetable origin, must always be looked upon with suspicion. The observation was made by Hippoc- rates twenty-three centuries ago, that persons using water from marshes, i.e., water containing vegetable matter, suffer from enlarged spleens. Many physicians, both of ancient and modern times, seem to have held this opinion, but the first positive observation in medical literature is the now classical one of the ship Argo, reported by Boudin.^^ In 1834 the transport Argo, in company with two other vessels, carried 800 soldiers from Bona, in Algiers, to Marseilles. The troops were all in good health when they left Algiers. All three of the vessels arrived in Marseilles on the same day. In two of them there were 680 men, not one of whom was sick. Out of the remain- ing 120 men who were on the third vessel, the Argo, 13 died during the passage, and 98 of the 107 survivors suffered from paludal fevers of all forms. None of the crew of the Argo were sick, however. The two vessels exempt from sickness, and the crew of the Argo, had been supplied with pure water, while the soldiers on the latter vessel had been furnished with water from a marsh. This water was sa'id to have a disagreeable odor and taste. The testimony of a large number of East India physicians is also quoted by Parkes in support of the view that malarial fevers are often caused by impure drinking- water. The observations of Dr. Charles Smart, upon the production of '^mountain fever" of the Western territories, have already been referred to. It is more than likely, however, that the cases on the Argo were typhoid fever. The causation of typhoid fever and cholera by impure drinking- water will be presently referred to. There can be very little doubt that diarrhea and dysentery are frequently caused by water which has been contaminated with de- caying organic matter. The evidence in favor of this amounts prac- tically to demonstration. Of course, in this as in the other instances cited disease is caused not by the organic matter, but by the specific bacteria with which the organic matter is usually associated. ^* Quoted in Parkes, op. cit., p. 48; Nowak, Lehrbuch der Hygiene, p. 51; and in numerous other publications on Hygiene. 5 66 TEXT-BOOK OF HYGIENE. It must not be forgotten that the ova of certain animai para- sites, such as distoma hematobium, filaria sanguinis hominis, and medinensis, anchylostoma duodenale, and possibly of round-worm are frequently present in polluted water. The relation of typhoid fever to the water-supply is probably the most important phase of the study of water from a hygienic stand- point. Typhoid fever is the disease most frequently caused by sew- age-polluted water, and next to tuberculosis and pneumonia it is the principal cause of sickness and death. There occur annually in the United States about 50,000 deaths from typhoid fever, the estimated number of cases being at least 500,000. The manner in which t3^phoid fever is caused by a polluted water-supply is as follows: The cause of typhoid fever is a bacillus discovered by Eberth and Koch, in 1880, and first isolated and studied in pure culture by Gaffky, in 1884. This bacillus is taken in with the food and drink which contain it, and is excreted from the body of the typhoid fever patient with the feces. The latter gains access to the nearest water- suppl}^, and the typhoid bacilli infect the water, which becomes the means of conveying the bacilli to other susceptible individuals. In this way epidemics of typhoid fever originate in towns and cities which are obliged to drink the sewage of other municipalities located on their watershed. Of course, there is always a possibility of direct infection by coming in contact with the patient's feces or urine, but such mode of transmission, while possible in isolated cases, cannot result in epidemics. Many instances are on record where outbreaks of tj^phoid fever have been clearly attributable to pollution of the drinking-water by the germ of the disease from a previous case. One of the most remarkable of these outbreaks is that recorded by Dr. Thorne.^^ About the end of January, 1879, typhoid fever be- gan suddenly in the adjoining towns of Caterham and Eed Hill. Within six weeks 353 cases occurred. All other sources of the disease were excluded except the drinking-water, to pollution of which it was traced with almost absolute certainty. Caterham contained 558 houses and Eed Hill 1700. Of the former 419 and of the latter 924 drew their drinking-water from a common supplj'', having its source in a well several hundred feet deep. The insane asylum, with 2000 inmates, and the military barracks in Caterham used water from a private well. There was no typhoid fever among the last two com- *' Report of the medical officer to the Local Government Board for 1879. Quoted in Fodor: Hygienische Untersuchungen, etc., II Abth., p. 261. DISEASES DUE TO IMPURE DRINKING-WATER. 67 mimities. During January one of the workmen engaged in some excavation near the public well was taken ill with diarrhea and fever, — probably typhoid — but was still able to continue his work. His dejections were often voided where they were certain to become mingled with the water of the common supply. This man's diarrhea began on January 5th and continued until the 20th of the month, during which time he remained at work. On the latter date he was compelled to quit work and take to his bed. Exactly two weeks from the beginning of the man's sickness, on January 19th, the first case of typhoid occurred in Caterham, and then rapidly increased. The first case occurred, therefore, just fourteen days — the incubative period of typhoid — after the presumed infection of the drinking- water by the dejections of the sick laborer, who had come from Croy- don, where typhoid fever was at the time prevalent. Within two weeks from the appearance of the first case the epidemic had reached its height, and then rapidly declined, disappearing almost entirely in a month after the outbreak. It was shown by Dr. Thorne that nearly all the houses in which the disease appeared were supplied with water from the source above mentioned, while other houses in the immediate vicinity of the infected ones remained free from the disease. In 1874 there was an outbreak of typhoid fever in the town of Over Darwen, in which nearly 10 per cent, of the inhabitants were attacked. Here the source of the disease was also traced to an in- fected water-supply. Dr. Buchanan has shown that an outbreak among the students of the University of Cambridge was likewise attributable to an in- fected water-supply. . In 1885 an epidemic of typhoid fever began in Plymouth, a mining town of 8000 or 9000 inhabitants, situated in the Wyoming coal region of Pennsylvania, and on the right bank of the Susque- hanna Eiver. The epidemic began in April, and lasted until the ensuing September. There were 1104 persons attacked by the disease, of which number 114, or 10.3 per cent., died. The careful inspection made into the history of this epidemic revealed the fact that the public water-supply had unquestionably become polluted by the fecal dis- charges of a single person who Avas affected with the disease. This man had visited Philadelphia on December 25. 1884, and while there contracted typhoid fever. He returned to his home, on the banks of the stream from which Plymouth derived its water-supply, in January, and was ill for several weeks. During his illness the fecal 68 TEXT-BOOK OF HYGIENE. discharges that were passed during the night were thrown upon the snow within a few feet of the stream. From March 21st to March 23d a thaw occurred, and during the early days of April there were fre- quent warm showers. As a result, the entire mass of dejecta which accumulated during this man's illness was washed directly into the stream. About two weeks later the epidemic broke out. In 1895, Grand Forks, IST. D., a village of about 6000 population, had 1500 to 2000 cases (25 per cent, of her population) and about 200 deaths. Previous to the epidemic the city water-supply was taken from the Bed Lake Eiver, which is a small, unnavigable stream. Twenty- four miles above Grand Forks, by car line, Crookston is situated, with a population at that time of about 3000. During the summer of 189-1 they had a good many cases of typhoid fever at Crookston. Their main sewer passed under one of the railroad embankments just before emptying into the Eed Lake Eiver. Some time during the summer the embankment crushed in the sewer, shutting it off. The sewage then came to the surface and formed a small stagnant pond held back l)y the embankment. This remained for about two months, continually increasing in amount. Just about the time that ice formed on the Eed Lake Eiver this sewer under the track was opened up and the dammed-back pond of sewage allowed to flow out rapidly underneath the ice. This was the time of year when the water in the river would be quite low, so that there was little chance for proper dilution and aeration. As a result, some two or three weeks after this sewage was opened, the young people of Grand Forks took sick by the dozens, then by the hundreds. The degree of virulency seemed to be unusually severe. In 1903, Ithaca, X. Y., the home of Cornell University, was stricken by a severe epidemic of typhoid fever. Of a population of 13,000, 1350 took sick and 78 died. The cause was traced to the pollution of the water-supply. During the same year an epidemic of typhoid fever occurred in Butler, Pa., a city of 18,000 population, in which 1348 persons were stricken within the short period of ninety days and 111 deaths occurred, as given in the report of the State Board of Health. This town was supplied with water from a stream more or less polluted, but just prior to the epidemic the private water company installed a me- chanical filter which was doing satisfactory work until October, when, on account of the changes in the pumping station, the filter was shut DISEASES DUE TO IMPURE DRINKING-WATER. 69 off at intervals to allow work to proceed on these changes ; and imme- diately there appeared the epidemic. Within ten days after the polluted water began to be pumped direct the physicians were overwhelmed with calls. . By N'ovember 39th the disease was so widespread and serious that a public mass meeting was called and a relief committee organized. In order to meet the expense of the committee $25,000 was voluntarily sub- scribed and it was estimated that $75,000 would be needed. Xurses and physicians were procured from Pittsburg, Philadelphia, and other places. The work at the station was rushed to completion at the earliest possible moment, but to December 17, 1903, there was a total of 1270 cases reported, with 56 deaths. In this case the infection was traced to the drainage from a miner's cabin in which there was typhoid fever. The drainage from this cabin was directly into a small branch, the flow from which en- tered into the stream from which the supply was taken, at a point a few yards above the intake to station. In 1904 an epidemic of typhoid fever occurred in Columbus, Ohio, with a population of 140,000. The number of cases was 1640, number of deaths 166. The source of the epidemic was traced to the pollution of the Scioto Elver with the sewage from the State Hospital. Quite recently a severe epidemic of tj^hoid fever occurred in Scranton, Pa. This epidemic was investigated by Dr. Eobin and the following are excerpts from his report: — "A visit to the Bureau of Health showed at a glance the serious- ness of the conditions as well as the determined eifort on the part of the officials to meet them successfully. Every desk in the office had behind it a busy worker. Dr. Keller, the superintendent, was busily engaged receiving reports and giving orders. Every few min- utes a messenger, police officer, or inspector came in with a report and for instructions. Physicians came in for information, and the telephones were in constant use. The whole aspect reminded one of army headquarters during an imjDortant battle. "On December 3, 1906, 5 cases of t3'phoid fever were reported to the Bureau of Health. From that date to December 12th, 20 cases were reported. There is every reason to suppose that typhoid cases occurred prior to that date, and in larger numbers than were reported, the attending physicians having diagnosed them as grippe. On De- cember 12, 24 cases were reported, and from that date up to January 70 TEXT-BOOK OF HYGIENE. 5, 1907, the number of cases reported reached 970, with 77 deaths attributed, of which 55 were officially reported. "The cases of typhoid fever are practically confined to the central part of the city and West Scranton, which were supplied with high service from the Elmhurst Eeservoir, The disease does not appear to be confined to any particular class of people, the rich and poor suffering alike, nor is there any relation of the epidemic to the sani- tary conditions of certain sections of the city. While the poor suffer most on account of a lack of means, and their sufferings are more in evidence, the well-to-do and the rich contribute their full quota to the morbidity and mortality list. The deaths of many prominent men and women have already been chronicled, and many a happy home has been shattered by this dread disease. "The consensus of opinion of all the officials, loc^l as well as State, with the exception of the Scranton Gas and Water Company, is that the water supply is to blame for the ei^idemic. The city of Scranton, with a population of about 120,000, is supplied with water obtained from mountain streams. These are intercepted by four small stor- age reservoirs of about 1,000,000 gallons each, and merge into what is known as Eoaring Brook. The latter empties into the Elmhurst Storage Eeservoir of a capacity of 1,600,000,000 gallons, and from this, overflowing a dam, passes through a pipe to No. 7 reservoir, from which the city is ordinarily supplied. A pipe-line also passes from the Elmhurst reservoir to Lake Scranton, a storage reservoir of 2,000,000,000 gallons capacity. When the flow over the dam at the Elmhurst Eeservoir is insufficient to supply the city, the supply is augmented by drawing on Lake Scranton. The watershed is sparsely populated and there are no large centres of pollution, the only village of any size being Moscow, with a population of about 900, which drains directly into the Eoaring Brook. However, two railroad lines pass along the branches of the Eoaring Brook, the Erie and D., L. & W., and these form a possible source of pollution. "The water-works are owned by the Scranton Gas and Water Com- pany and are estimated by the owners to bo worth $13,000,000. "The water has been of good quality and there is no record of any marked pollution of the supply, nor wou^d the mortality of typhoid fever in the past indicate that the supply was not comparatively pure. In the report of the Bureau of Health for 1905, the following state- ment is made : — " ^The city of Scranton can proudly boast of its pure and unlimited water supply, as also the protection given to its water-sheds. The bac- DISEASES DUE TO IMPURE DRINKING-WATER. 7I teriologist, Dr. Wilson, has, on numerous occasions, examined speci- mens from the different reservoirs at different times, and found them in excellent condition.' This statement seems to find corroboration in the low typhoid fever mortality, the deaths from typhoid fever being in 1905-1906, 11 and 25 respectively. "However, amidst all this security and confidence, the blow struck. Whether the sudden contamination of the water-supply came from passengers suffering or convalescent from a mild form oi typhoid fever, on either, or both of the railroads; whether it came from one or more of the hunters who have hunted on the water-shed; whether from some visitor at the hotel at Moscow, which drains into the Eoaring Brook, is not known. The fact, however, is that the sup- ply in the Elmhurst Eeservoir was found badly polluted, and what is of the greatest importance, the typhoid bacilli have been actually discovered in some of the samples of water analyzed at the State Laboratories at Harrisburg. This, I believe, is the first instance in this country of actually demonstrating the presence of typhoid bacilli in water suspected of causing typhoid fever. In view of this fact, I made special inquiries, and was assured by Dr. Johnson and Mr. Snow that the bacillus which the State bacteriologist isolated from the water, responded to all the cultural and other tests, and was found identical with the typhoid bacillus isolated from the discharges from typhoid patients at Scranton. This remarkable and unique demon- stration establishes beyond doubt not only the cause of the Scranton epidemic, but the relation of water-supplies to typhoid epidemics in general. "As a result of these findings the supply from Elmhurst Eeservoir has been cut off and the city of Scranton is supplied from Lake Scran- ton. As a further precaution, the health authorities have urged the people to boil the water and milk, a precaution which is generally being observed. "It should be noted that the health authorities have shown re- markable ability and zeal in coping with the serious situation. Daily bulletins apprise the people of the exact situation, while thorough disinfection of the premises is rigorously enforced. The hospitals and charitable institutions have lent their entire forces to meet the conditions prevailing at the present time, while the press has all along supported and helped the administration. As a result there is no panic. The situation is viewed calmly and sensibly, and there is every reason to believe that the epidemic will soon be under control. "The Scranton epidemic still further emphasizes the fact, long 72 TEXT-BOOK OF HYGIENE. ■^S •^ a =6 sh' S I (3 - 1^ rf Tt< CO cq o o oi c^oooQOoooococot^ ?o?ococot©?oco co«Dy?io 3 1^ «■ § ■§■ h fiS 03 a a 0) a ca % •a ft i a a a .a cs 2 a 3 (D d O a, 03 CIS a ►-5 a •2 <1 3.2 a 3 a o a, 00 j>. r^ lO T)i T)< ■*co ,_, o OS lO lO in la lO Iffl U3 10 lO T)l >< "^ ^ boo H Ph . bo ^ ^1 Mm il .d ^ q ^ Dh. « S a 2 5 a a ^ 4^a g||T^"S i O pH;HHM<)t^tHp<< p:OMOlZiMSft <1 3 C3 O > (g-H « ^ |zi fuS a bo fc C3 Oj P5 Ph S ^ DISEASES DUE TO IMPURE DRINKING-WATER. 73 h fe » s tf S d :i oj 5 tii S) 2 .s e .s £ a) a a c3 ;h S) > '3 «^ "So la m 3 "-' o a _C3 o a "3 a > 2 <1 O O o S PS CO Ph SI <1 O 03 ■S rt O CO 1 -35 2 2 05 (33 CO 00 t~ o cc lO lO IC lO lo Tl< '^ M ^^'^■^■^■^Tt'TfcOCO cocccocococo p= ^ a <5 > (M iM ef c3m Zi ri Zi gOOOOS^moO OO30O0CO t^^ w ^'2 2- 03 a a ■* tC -* t)< tJ) CO CO coco COCO?3COCOC^CsiC^ C^C-IC^C^ (MC CC r-l 00 u y ,0 Vh >» 8 a « u HJ "S a <;i s ^ ^ .g in 0) i?> _a 10' —. o ^ &? 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CO coco CO CO CO S ^ _w n o — aj ^ n "3 .M O jT 03 a Ph p: h4 O fl i w g M bo a -B 03 -d a a^ 1^ -^f^ g C OS 2 a a .^ 53 O. -" OS 5 iJ M ft "" a o ^ 13 as oj a a a "t:i c3 ft 3 5 ° t2 a a "» "3 Q fin &: 5 <| m ^^o oo o^c^c^ O^OOOOCOCOOO C<1 C^(N IM C^ rl o a Aw ^ (^ t;J - S t* - ^ .2 - f^l !U' « 3 S ?i ^ a M ^ -M -S c;T3 m •^ 5" g 2 ^V S 5 in oo '^ o 5 is a &!-> g -^^i 0) a> ^■^- « S .2 ,■« " « 2 .t; o o S-g >!. £ i «J3 £^- g « .a S 2 v? o ^ -3 -fl 3 o § o/ yj % 7j t/j ;^ u* m P fa W W 1-^ « Hi 1< M fi 3 iz; aa O W i-l S PQ fS M 3 fa pq W (H rt N a -^ 3 o 76 TEXT-BOOK OF HYGIENE. ago recognized in Europe, that no surface water is safe without j&nal purification, and that an ounce of prevention is worth many pounds of cure." Tlie above-cited epidemics emphasize the danger confronting every municipality in this country that depends on a surface water for its supply. In fact, Pittsburg and Allegheny, and Philadelphia, are subjected to annual typhoid epidemics which, in point of destruc- tion of human lives, exceed any other agency of death. For the last 14 years there have been reported in Pittsburg some 30,000 cases and over 4200 deaths. The relation of typhoid fever to the water-supply of the large American cities is best shown in the table on pages 72 to 75. On the other hand, Hague, Berlin, Eotterdam, Breslau, Ham- burg, Zurich, Amsterdam, London. Edinljurgh, and Warsaw, European cities supplied with water filtered through slow sand filters, have an average typhoid mortality of 8.3 per 100,000. As it is with typhoid fever, so also with cholera. In the instance to be presently noted the connection between the infected water, on one hand, and the outbreak of cholera, on the other, is so clearly shown as to be almost equivalent to a mathematical demonstration. The facts in the case were brought to light after a patient inquiry by a commission, whose report drawn up by Mr. John Marshall has made the occurrence classical. In 1854 the people of a Avell-to-do and other- wise healthy district in the eastern part of London suffered severely from cholera. L^pon inquiry the fact was elicited that a child had died of cholera at No. 40 Broad Street, and that its excreta had been emptied into a cess-pool situated only three feet from the well of a public pump in that street, from which most of the neighboring people took their drinking-water. It was further discovered that the bricks of the cess-pool wall were loose and permitted its contents to drain into the pump-well. (It should be noted that the communica- tion between the cess-pool and the well was direct; that there was immediate drainage, not percolation through the soil.) In one day 140 to 150 people were attacked, and it was found that nearly all the persons who had the malady during the first fcAV days of the outbreak drank the water from the pump. When the pump was closed to public use by the authorities the epidemic subsided. The most singular case connected with this outbreak was the following: In West End, Hampstead, several miles away from Broad Street, there occurred a fatal case of cholera in a woman 59 years old. This woman formerly lived in Broad Street, but had not been there for many months. A STORAGE AND PURIFICATION OF WATER. 77 cart, however, went daily from Broad Street to West End, carrying, among other things, a large bottle of water from the pump referred to. The old lady preferred this water to all others, and secured a daily supply in the manner stated. A niece, who was on a visit to the old lady, drank of the same water. She returned to her home, in a high and healthy part of Islington, was likewise attacked by cholera and died. There were, at this time, no other cases of cholera at West End, nor in the neighborhood of these last two persons attacked. Most of the English medical officers in India hold strongly to the view that cholera is spread by polluted drinking-water, and the evi- dence in its favor is very strong. In 1885 Dr. Eobert Koch discovered the cholera spirillum in a water-tank in Calcutta, used as a source of domestic supply, and in this way furnished another link in the chain of evidence connecting the spirillum, the drinking-water, and the outbreak of the disease. The evidence in favor of the influence of impure drinking-water on the causation of other diseases than those mentioned is not suffi- cient to justify any conclusions at present. The source of a water-supply may be pure, yet pollution may occur before the water is used by persons to whom it is distributed. Supply-pipes may become defective, and the water become contamin- ated with sewage or other deleterious substances. Aside from the practical question of the causation of disease by polluted water, a more abstract and esthetic idea is involved in con- sciously taking any impurity into the system. The instincts of man, as well as of most animals, revolt at it. These inborn instincts, which constitute the sanitary conscience, as Soyka says, demand purity of food and water, as they insist on cleanliness of the body, of clothing, and of the dwelling. STORAGE AND PURIFICATION OF WATER. Wherever a large supply of water is needed, unless drawn direct from a well or spring, or pumped directly from its source, arrange- ments for storage are necessary. Cisterns and large reservoirs are made use of for this purpose. Eiver-water, especially, requires a period of rest, in a storage reservoir, in order to allow deposition of the large amount of suspended matter in it. Prolonged storage also gives opportunity for the conversion of possibly deleterious organic com- pounds into simple and perhaps harmless combinations. Usually, in an elaborate system of water-works, a series of reservoirs is built, in 78 TEXT-BOOK OF HYGIENE. which the water is stored successively, so that before its final distribu- tion through the street-mains it has become quite clear and pure. Filtration on a large scale is also used in connection with storage reservoirs in order to secure greater purity of the water. In the distribution of water, care should be taken that nothing deleterious is taken up by the water in its passage through the pipes. Lead-poisoning is not infrequent from drinking-water that has passed through a long reach of lead pipe, or which has been standing in a vessel lined with lead. Tanks and storage systems should therefore not be lined with lead, and the use of lead pipe in the supply service should be avoided as much as possible. Fortunately, most natural waters possess a considerable portion of carbon dioxide, which forms with the lead an almost insoluble carbonate of lead. This carbonate of lead is deposited on the inside of the pipes, and protects both the pipes against erosive action from other constituents of the water, and also prevents the contamination of the water by the lead. An excess of carbon dioxide in the water renders this deposit soluble, and may cause serious poisoning. Any water which is shown by analysis to contain over 1 milligramme of lead per 100,000 is dangerous and should be rejected. Owing to the possibility of defilement of the water from improper construction of hydrants, all outdoor hydrants should be discouraged as much as possible, and should be replaced by a simple tap-cock indoors. The pipes should also be laid deep enough under-ground, or otherwise protected against freezing in winter. A number of methods, all more or less efficient, have been intro- duced to purify water when it needs purification before being fit for use. These methods either comprise filtration or seek to purify the water without the aid of this process. One of the methods of puri- fication without filtration consists in exposing the water to the air in small streams. This was proposed by Lind, more than a century ago, and has since been frequently revived. The water is passed through a sieve, or a perforated tin or wooden plate, so as to cause it to fall for a distance through the air in finely-divided currents. By this process sulphuretted hydrogen, offensive organic vapors, and possibly dissolved organic matters are removed. This process has been used in Eussia on a large scale. By boiling and agitation, carbonate of lime, sulphuretted hydro- gen, and organic matter are removed or rendered innocuous. Vege- table germs are usually destroyed, although Tyndall has shown that some bacterial germs withstand a temperature higher than that of STORAGE AND PURIli*ICATION OF WATER. 79 boiling water. Pathogenic germs are, however, all destroyed by boil- ing water acting on them for ten minutes, as shown by Dr. G. j\I. Sternberg.^* As has already been mentioned/^ alum is one of the readiest and most efficient means of removing suspended matters from water. However, it should not be used in large quantities. Permanganate of potassium is sometimes used to purify water containing considerable organic matter. The permanganate rapidly oxidizes the organic matter, and is believed to render it harmless. There is no certainty, however, that the germs of specific diseases are destroyed by the action of this salt, in the proportion in which it could be used for the purposes of water purification. A yellow tint is given to the water by the permanganate, which is due to finely-divided peroxide of manganese. This does no harm, but is unpleasant. Bromine has been used for a similar purpose, and is claimed to give very good results. The bromine may be neutralized by ammonium or other alkali. In 1904, Moore and Ivellerman,^*' of the Bureau of Plant Indus- try, United States Department of Agriculture, advocated the use of copper sulphate, first for the destruction of algae, and later for the purification of water. They found that in proportion of 1 : 100,000 copper sulphate is an efficient germicide, destroying the colon and typhoid bacilli. It was also discovered that copper vessels are capable of purifying water through action of the colloidal copper which is taken up by the contents. For a time these claims received enthusi- astic endorsement from many quarters, and it seemed as though the difficult problem of water-purification in a ready manner had been satisfactorily solved. However, the enthusiasm cooled down consider- ably when reports began to appear from various laboratories, show- ing that the claims of Kellerman and his followers are greatly over- drawn. Aside from the fact that it would not be safe to introduce copper sulphate into the system, even in minute and theoretically harmless quantities, for a long time, the fact has been brought out that the germicidal action of copper is very uncertain. Among the bacteriologists who reported adversely to this new method, Clark and Gage, of the Lawrence Experiment Station, have furnished the most damaging evidence. In an article on the bactericidal action of copper^'^ the authors very properly emphasize that "the weak point " Report of Committee on Disinfectants, 1888. " See page 64. "U. S. Dep't A^mculture. Bur. Plant Ind., Bull. No. 64. "The Jour, of Inf. Diseases, Supplement No. 2, Feb., 1906. 80 TEXT-BOOK OF HYGIENE. in tlie conclusions of Moore and Kellerman with regard to the de- struction of typhoid by copper is that they were drawn from analy- ses in which the largest amount of water tested was 1 c. c, and the usual amount tested was less than .01 c. c, It is generally conceded, especially when dealing with laboratory cultures, that the great ma- jority of the typhoid bacilli are quickly destroyed by conditions un- favorable to their growth. It has also been repeatedly shown that a few germs are much more resistant than the majority, and may sur- vive even under the most unfavorable conditions for many days. All epidemiological evidence points to the conclusion that the germs which are able to live under unfavorable conditions are also extremely patho- genic, and that, while it may help to destroy the majority of the bacilli, no method of sterilizing water is thoroughly effective unless it will accomplish the destruction of the especially resistant indi- viduals. "It is unsafe to conclude that because a certain species of bac- teria, especially a pathogen like B. typhosus, is not found in a loopful of the water, or even in 1 c. c, that there is no danger from the use of that water. The average drinking-glass holds about 300 c. c, and until repeated tests of volumes as large as 100 c. c. have been made and the germ proved to be absent, the water under observation can- not safely be said to be free from the test forms." The authors have used large quantities of water in their experi- ments and have varied the experiments to cover the ground thor- oughly. Their conclusions are: — "The treatment of water with copper sulphate or by storing it in copper vessels has little practical value, for the following reasons: — "1. The use of any method of sterilization which is not absolutely effective is dangerous in the hands of the general user, tending to induce a feeling of false security, and leading to the neglect of or- dinary precautions which would otherwise be employed. "2. The removal of bacteria, B. coli and B. tj^phosus, by allowing a water to stand in copper vessels for short periods, while occasionally effective, is not sure, and the time necessary to accomplish complete sterilization is so long that the method would be of no practical value to the ordinary user. Furthermore, metallic copper seems to have little more germicidal power than iron, tin, zinc, or aluminum. "3. Although the removal of B. coli and B. typhosus is occasion- ally accomplished by dilute solutions of copper sulphate, these organ- isms may both live for many weeks in water containing copper sul- phate in greater dilutions than 1 : 100,000; and in order to be safe STORAGE AND PURIFICATION OF WATER. 81 dilutions of 1 : 1000 must be used, in which case the water becomes repugnant to the user because of its strongly astringent taste. "4. In some instances very dilute solutions of coj^per sulphate or colloidal copper absorbed from contact with clean metallic copper, appear to have a decidedly invigorating effect on bacterial activity, causing rapid multiplication, when the reverse would have been true had the water been allowed to stand the same length of time without any treatment." Eegarding the effect of copper and other metals on B. coli, the authors found that the organism disappears under the action of the respective metals in the following number of days: zinc, 10 days; iron, 15 days; tin, 41 days; aluminum, 41 days; copper, 43 days; lead, 97 days; and in another experiment: zinc, 10 days; copper, 10 days; tin, 23 days; iron, 23 days; lead, 23 days; aluminum, 31 days. Filtration. — The purification of water by filtration has been shown to be the most reliable means of removing both suspended mat- ter and bacteria from polluted water. Filtration is practiced on a small scale — domestic filters — and on a large scale. Of the domestic filters only those made of unglazed porcelain (the Pasteur filters) or infusorial earth (the Berkefeld filter) are to be relied upon. These filters are made of a porous material, the pores forming tortu- ous channels in which the bacteria lodge and are retained. After a time the filter becomes permeated with bacteria and the latter are pushed through, as it were, by the incoming armies. To make them yield a satisfactory effluent, the filtering unit should be frequently scrubbed and sterilized in the oven or by boiling at least once a month. Maignen's domestic filter, made of granulated charcoal and asbestos, is said to be quite satisfactory. All other domestic filters on the market, and their name is legion, are practically worthless, if not actually harmful because of the false security which they give. On a large scale, water may be purified by sedimentation, slow sand-filtration, or the English method, rapid sand-filtration, or the American method, which is also known as mechanical filtration. In the process of sedimentation the water is confined in one or more large reservoirs holding 30,000,000 to 50,000,000 gallons and allowed to become clarified by the particles of mud falling to the bot- tom. Incidentally, the bacteria are carried down and some oxidation of the organic matter takes place. Usually about 75 per cent, of purification takes place by this method. In St. Louis the water is treated with iron sulphate and lime before final sedimentation. By TEXT-BOOK OF HYGIENE. STORAGE AND PURIFICATION OF WATER. 83 Fig. 5. — Plans of Intake and Water-tower Used in Connection with the Reservoir. 84 TEXT-BOOK OF HYGIENE. this method the effect of sedimentation is greatly enhanced and the purification of the water is much greater. Slow Sand FiLTRATioisr. — This method was originally employed by the London water companies as a means of removing from the water the matter in suspension. Later, however, Frankland ha? shown that the sand-filters also remove the bacteria or most of them, and thus purify as well as clarify the water. Since 1890 the Massachu- setts State Board of Health has been conducting extensive experi- ments on slow sand-filtration, and it is these experiments that have elucidated the subject of filtration and placed it on a solid scientific basis. The principle underljdng slow sand-filtration is a biologic one. The forces which bring about purification of the water in the sand-filter are exactly the same as operate imder natural conditions when a foul surface pool percolates slowly through the ground and crops out in the form of a pure, sparkling spring. The upper layers of the ground swarm with various bacteria which live on dead organic matter, so-called saprophytes. Among them are certain species which convert the nitrogenous substances into ammonia; others convert the ammonia into nitrites and nitrates, the so-called nitrifying bacteria; again others break up cellulose; in a word, the organic substances of the water are attacked from all sides and converted into harmless mineral substances, the latter to be taken up by the plants as food. If any pathogenic bacteria happen to be present they find a strange and altogether uncongenial environment. In the first place, they are accustomed to body-heat, and the comparatively low temperature chills them; then, they are parasitic in nature and cannot prepare food for themselves, while the food that they find is rapidly consumed by their competitors, which are in greatly predominating numbers. Thus, the pathogens soon perish and are rapidly consumed by the saprophytes. Tliat this is not a fanciful representation may be demonstrated by laboratory experiments, which will show, for in- stance, that anthrax bacilli are rapidly destroyed in putrefying blood ; that typhoid bacilli soon disappear in feces; that any of the patho- genic bacteria are quickly crowded out in cultures which contain also saproph3^tic bacteria. Conditions very much similar to those existing in nature prevail in the slow sand-filter. Here we have a bed of fine sand about three feet thick, through which the water percolates at a rate of 3,000,000 to 4,000,000 gallons per acre per day. While the water passes through the sand, the suspended matter is strained out and is deposited be- tween the sand-grains, in the upper inch or two. The infusoria, algae, STORAGE AND PURIFICATION OF WATER. 85 and bacteria in the water become entangled in what is now a very fine sieve and form a slimy film about the sand-grains, on the surface of the bed. No sooner are the various bacteria domiciled than they at once commence to work, each species performing its particular function and making a struggle for existence. The surface film of the sand-bed, or what the Germans call '^schmutzdecke" (mud-film), is now teeming with life and is the field of energetic biologic activity, the result of which is the transformation of the complex organic molecules into simple inorganic compounds. Any pathogenic bacteria that may be present in the water become enmeshed in this film and soon perish in the unfavorable environment. In time the upper mud- Fig. 6. — Plans of Slow Sand Filters. These consist of concrete basins, on the floor of which are laid tile or terra cotta underdrains; over these, from three to six inches of gravel in successive layers, beginning with the very large sizes at the bottom and the finest at the top; over this about three feet of fine sand, and over this three to four feet of water. film becomes more and more compact, until only a comparatively small amount of water passes through. This happens, under ordinary circumstances, about once in three weeks. Whan this occurs, the filter is drained, the upper inch of sand removed by means of shovels, and filtration resumed. The greatest impetus to filtration and the most remarkable demonstration of its efficiency in preventing water-borne diseases were furnished by the epidemic of cholera which visited Hamburg in 1893. The cities of Hamburg and Altona are separated by an imaginary line, so that nothing in their surroundings or in the nature of their popula- tion distinguished one from the other. Both cities depend for their 86 TEXT-BOOK OF HYGIENE. water-supply on the polluted river Elbe, with this difference, that while the intake for Hamburg is situated above the city, that for Altona is situated below Hamburg, i.e., the water-supply of Altona receives additional pollution of some 800,000 inhabitants. When the epidemic broke out Hamburg suffered a loss of 1250 lives per 100,000, while the number of deaths in Altona was only 221. So clearly defined was the path pursued by the epidemic that in one street which marks the division between these towns, the Hamburg- side was stricken down with cholera, whilst that belonging to Altona remained free. It was found that in the houses supplied with the Hamburg water cholera was prevalent, whilst those furnished with Altona water remained free from the disease. iSTow, the reason for this difference was in the fact that Altona filtered the water, Avhile Hamburg did not. Fate, moreover, furnished additional proof of this fact. During the ensuing winter, when the epidemic of cholera had almost died out in Hamburg, an outlireak of the disease occurred in Altona. A searching inquiry was instituted and it was found that instead of the usual small number of bacteria in the effluent from the filters, al)out 50, the number rose to 1000 and more in a c. c. The cause for this inefficiency was soon discovered. It was found that one of the sand-filters, which had been cleaned during the frost, had become frozen over, and was consequently not able to retain the bac- teria. But imperfect as the filters then were, they nevertheless saved the city from another severe epidemic, as shown by the limited num- ber of cases. As a result of his studies of the Altona filters. E. Koch arrived at the following conclusions : — 1. The real effective agent in removing micro-organisms from the water is the layer of slimy organic matter which forms upon the sur- face of the sand. 2. If this surface l^e removed by scraping, or its continuity af- fected in any way, as by freezing of the surface, the number of bac- teria which pass through the filter increases considerably; in fact, both cholera and t5rphoid germs may pass in sufficient numbers to cause an epidemic amongst those who use the imperfectly filtered water. 3. Filtration should not exceed a rate of 2,000,000 gallons per acre. 4. After a filter-bed has been scraped, water should be allowed to stand upon it for at least 24 hours to allow of the slime depositing before filtration is commenced and the water which first passes should be wasted. STORAGE AND PURIFICATION OF WATER. 87 5. Each sejoarate filter-l)cd must, when in use, be investigated bacteriologically once each day. 6. Filtered water containing more than 100 bacteria per cubic centimetre should not be allowed to reach the pure-water reservoir. Perhaps no single investigation has contributed as much towards our knowledge of the underlying principles of filtration as the experi- ments performed at the laboratories of the Massachusetts State Board of Health since 1890. The more important results of these experiments may be sum- marized as follows : — 1. The depth of sand, within certain limits, exerts but little influence on the efficiency of a sand filter, except when the rate of fil- tration is high; with moderate rapidity of filtration (2,000,000 gal- lons per acre daily) one foot of sand is as effective as five feet. 2. The effect of scraping the sand to remove the clogged surface is to cause an increased number of bacteria to pass through the filter. Usually the filter requires three days' use after scraping to reach a maximum degree of efficiency. The effect of scraping is more marked in shallow than in deep filters, and with high rates than with low rates of filtration. 3. Over 80 per cent, of the bacteria removed are found in the upper inch of sand, and 55 per cent, in the upper quarter-inch. The B. prodigiosus, which is very like the typhoid bacillus in its mode of life in water, was not found below the upper inch. 4. The average depth of sand necessary to be scraped from the surface of the filter was ^/^ inch, but was found to vary with the size of the sand, decreasing as the fineness of the sand increased. 5. Much less water will pass a filter at 32° F. than 70° F., owing to the increased viscosity of the water. 6. Within certain limits and under equal conditions the quantity of water passed between successive scrapings is not influenced by the rate of filtration. 7. Finer sands require more frequent scrapings than coarser sands. 8. Shallow filters require more frequent scrapings than deeper ones. 9. During the summer months the temperature and other con- ditions for continuation of life of bacteria at the surface of filters are more favorable than at any other time. Experiments performed at Wilmington, Del., by Dr. A. Eobin, indicate that excellent efficiency may be obtained at a rate of 4,000,- 88 TEXT-BOOK OF HYGIENE. 000 gallons per acre per day, if the raw water is passed, previous to filtration, tlirongh a preliminary filter, which removes about 50 to 75 per cent, of the turbidity and bacteria. Following the remarkable demonstration of the efficiency of slow sand-filtration in removing cholera bacilli from the water, sand-filters were installed in almost all the large cities of Europe, and wherever installed have reduced t^^phoid mortality to a very small percentage. In this country, the first slow sand-filter was built by Kirk- wood, in Poughkeepsie, N". Y., in 1877. This filter, however, was operated without any particular regard to the scientific aspect of fil- tration, and under disadvantageous climatic conditions. The first filter which has contributed very largely to our know- ledge of the subject, and which has served as a model for other plants, is the slow sand-filter constructed in Lawrence, Mass., in 1893. This filter has been in operation ever since, giving excellent results both as to the improvement of the polluted Merrimac water and the reduc- tion of the typhoid mortality in the city. This is shown in the fol- lowing table : — Table XI. Death Rate Per 100.000. Year. Before Filtration. Year. After Filtration. 1885 42.0 1893 86.6 1886 57.5 1894 50.0 1887 117.5 1895 18.6 1888 120.0 1896 16.2 1889 137.5 1897 13.9 1890 133.3 1898 33.0 1891 122.0 1899 18.1 1892 111.1 1900 18.0 Following the introduction of slow sand-filtration in Lawrence, slow sand-filters have been constructed in a number of American cities, the most notable of which is Albany, ]^. Y. In the latter city a covered slow sand-filter was constructed by Mr. Hazen in 1899. The improvement in the mortality from typhoid fever and diarrheal diseases has been very marked, as shoT\Ti by Mr. Bailey, the superin- tendent, in his report for the year ending 1901 : — "An examination of the health records of the city shows some interesting features coincident with the commencement and continued operation of the filter, as follows: — STORAGE AND PURIFICATION OF WATER. 89 Table XII. Death Record. General Diarrheal Typhoid Av. Av. Av. previous previous previous 10 10 10 yrs. 1899 1900 yrs. 1899 1900 yrs. 1899 1900 October 153 138 144 5 2 5 4 4 5 November 162 138 135 3 1 5 4 December 194 148 133 6 1 7 1 1900 1901 1900 1901 1900 1901 January 235 135 188 6 1 2 11 3 2 February 197 146 157 6 2 11 1 3 March 215 180 164 5 5 1 12 3 1 AprU 197 202 156 4 1 9 5 1 May 173 152 139 3 1 4 4 1 June 159 112 145 10 7 1 4 1 3 July 191 162 142 39 27 11 4 3 August 162 116 134 21 16 14 7 6 3 September 148 125 139 12 5 12 6 4 4 Total ...2186 1754 1776 120 67 48 84 35 27 Reductions, per cent... 19.77 18.76 44.17 60.00 58.33 67.86 "There has been no general sanitary improvement in the city in this time other than the improvement of the water due to filtering. These figures show facts, and should be susceptible to accurate inter- Fig. 7. — Showing Interior of Filter Recently Constructed in Washington, D. C. 90 TEXT-BOOK OF HYGIENE. pretation. My inference from them is, that, as a result of the pure water now being supplied, there is a better general condition of health, as shown by a decided reduction in diseases caused by filth and disease-germs that are water-borne." The Albany filter has continued to give excellent results from a sanitary standpoint. Slow sand-filters have been constructed in Prov- idence, E. I., Washington, D. C, Hudson, IST. Y., Mount Vernon, N. Y., Far Eockaway, L. I., Ilion, IST. Y., Yonkers, N. Y., Somers- worth, N. H., Ashland, Wis., Superior, Wis., St. Johnsbury, Vt., Milford, Mass., Nantucket, Mass., Nyack, IST. T., Lambertville, X. J., Salem, N. J., Eock Island, 111., Grand Forks, IST. D. ; and are in the course of construction in Philadelphia, Pa., Pittsburg, Pa., and Wil- mington, Del. Our experience thus far gained from the results of filtration enables us to make the general proposition that properly filtered water is fully equal in its hygienic purity to a pure supply from natural sources. This is shown by Hazen in the following table: — Table XIII. Deaths from Typhoid Fever per 100,000 per Annum. to (D g-§ fio few (^< Ph« Zurich, Switzerland Filtration. 1885 76 10 87 Hamburg, Germany Filtration. 1892-93 47 7 85 Lawrence, Mass Filtration. 1893 121 25 79 Albany, N. Y Filtration 1899 104 28* 73 Lowell, Mass., Kiver water to ground water 1895-96 97 21 78 Newark, N. J., Eiver water to upland water 1892 70 16 77 Jersey City, N. J., River water to upland water 1896 77 24 69 Averages 85 19 78 *Fuur years. Mechanical Filters. — In the mechanical, rapid or American system of filtration, the water is conducted through sand in about the same manner as in slow sand-filters. In a mechanical filter the action is both mechanical and chemical, the foreign substances in the water STORAGE AND PURIFICATION OF WATER. 9| being retained in the sand mechanically, while their retention is aided by the ajoplication of chemicals. There is no biological activity in a mechanical filter as there is in the slow sand-process. By reason of the assistance of the chemicals, and by virtue of the absence of the biological activity on a mechanical filter, it can be operated at much higher rates than slow sand or '^Diological" filters as they may be called. The usual rate at which mechanical filters are operated is 125,000,000 gallons per acre per day, while slow sand- filters are operated at about the rate of 3,000,000 gallons per acre per day. A more rapid passage of the water through a slow sand-filter would be liable to wash the bacteria from the sand-grains about which they live, and so interfere with the successful operation of the filter. The chemicals usually used in mechanical filters are sulphate of aluminum or sulphate of iron and lime. The way these chemicals act is as follows: When sulphate of aluminum is used, it is led into the supply somewhere before the water enters the filters and there combines with the lime naturally present in nearly all waters to form hydrate of aluminum and sulphate of calcium. The sulphate of cal- cium remains in solution in the water, but the hydrate of aluminum, being insoluble, agglomerates, by means of its stickiness, the bacteria and other particles in suspension in the water, into masses of such size that they cannot pass between the sand-grains as they would if they had not been massed together by the action of the chemicals. When sulphate of iron and lime are used, the action is exactly similar, only instead of having hydrate of aluminum we have hydrate of iron. Having all the foreign particles in the water agglomerated in one of these ways, they are much more easily retained by the sand than in the slow sand process, consequently the filter can be operated at a more rapid rate. Being operated at a more rapid rate, the dirt accu- mulates on the surface of the sand faster than it does in a slow sand plant, with the consequent necessity of more frequent cleaning. In mechanical plants the cleansing of the sand is accomplished by turning a current of filtered water upward through the sand, and at the same time agitating the whole bed of sand by means of rakes driven mechanically or by compressed air forced through the sand from below. By either means of agitation the sand-grains are forced rapidly against each other and all foreign matter is forcibly removed from their surfaces, and carried by the current of water to the top of the filter, whence it is conducted to the sewer by pipes arranged for that purpose. The operation of cleaning a mechanical filter usu- ally takes abont ten minutes, and the frequency with which it has 92 TEXT-BOOK OF HYGIENE. to be performed depends entirely upon the character of the water treated. Ordinarily a filter has to be cleaned about every twenty- four hours, and it requires from 3 per cent, to 5 per cent, of the fil- tered water for cleaning purposes. Eegarding the efficiency of mechanical filters, it may be said that, when carefully constructed and skillfully operated, they give hy- gienic efficiency equal to that of a slow sand-filter; but, on the other hand, the mechanism of operation is much more complex, the ^^ossi- bility of some unlooked-for derangement greater, with consequent lia- bility to get out of order and thus result in imperfect purification of the water. The comparative utility of slow sand and mechanical filters was summarized by Col. A. M. Miller, John W. Hill, and Eudolph Her- ring, acting as a commission of experts for Pittsburg, Pa. The fol- lowing is an extract from their report, and the conclusions deduced : — "It was found by the experimental work carried on by the former commission, for Pittsburg conditions, that as to first cost mechanical filtration was the cheaper process. Upon reviewing the subject at the present time, we are of the same opinion, but would add that the ex- pense of operation being greater for the mechanical filters, the total expense of the two methods becomes nearly equal, and the preference should depend on other than financial considerations. "As to efficiency in removing l^acteria, the preference between the two methods is not marked, provided constant intelligent care is given in equal measure to manipulation of both processes. "It cannot be denied, however, in the absence of such care, that if any irregularity occurs in the operation of the system, the rapid or mechanical filter would present the greater danger, by passing a much larger quantity of unfiltered water into the mains, before a proper correction is likely to be made. "As to the adaptability of the effluent for steaming purposes, the weight of evidence is decidedly in favor of s^.ow sand-filtration. It was found by the Filtration Commission of 1897, that the latter pro- cess caused less scale and less corrosive action on the plates of steam boilers. "Slow sand-filters are to be preferred from the standpoint of op- eration. Slight neglect or inattention, or mistaken judgment in the management of the filters, cannot at once seriously damage the efflu- ent. Eapid or mechanical filters require an exact proportionment of coagulant day by day. and sometimes hour by hour to obtain the de- sired results. While such careful attention can sometimes be attained, Fig. 8. — Showing Exact Size of Filtering Material Used in Con- struction of Sand Filter. (By courtesy of tlie Pittsburg Filter Manu- facturing Company.) pq be EXAMINATION OF WATER. 93 it nevertheless must be admitted that the simplicity of operation of the slow sand-filters is a decided advantage. "We therefore are of the opinion that slow sand-filtration as recommended by the Commission which reported to Council in 1899, is most suitable because : — "1. It is most simple and durable. "2. It is most effective imder existing circumstances. "3. The cost of construction and operation is reasonable, and, according to careful estimates, no greater than for any other practic- able system." Similar views are expressed in a very excellent report submitted by Mr. T. A. Leisen, chief engineer of the Wilmington Water De- partment. Other Methods of "Water Purification. — Of the other methods, the use of ozone is the only one deserving consideration. There is no doubt that ozone destroys the bacteria in the water without in any way changing its composition. However, the method is still in the experimental stage, and its utility on a large scale remains to be demonstrated. EXAMINATION OF WATER. The average consumer judges of the quality of the drinking- water by means of his special senses of sight, smell, and taste. Water which is turbid or emits a disagreeable odor is unreservedly con- demned, while clear, sparkling water free from odor is just as un- qualifiedly pronounced "pure." Those of us who are familiar with the history of typhoid epidemics and have had opportunity to examine drinking-water by means of special methods know how fallacious such a crude judgment is. Water that is clear and sparkling may contain the germs of typhoid fever or may be polluted with sewage which, in the course of decomposition, gave rise to carbonic acid. It takes many billions of bacteria to render a glass of water perceptibly turbid, and it requires considerable fresh sewage to impart to it a fecal odor. On the other hand, a turbid water, although objectionable from an esthetic point of view, may be entirely wholesome, and a dis- agreeable odor may be due to inoffensive vegetable compounds or harmless algge. This evident inability to form a ready judgment of the quality of a drinking-water has led the sanitarian to seek the aid of the chemist, who, it was supposed, could readily detect by means of 94 TEXT-BOOK OF HYGIENE. chemical analysis the injurious substances in the water under sus- picion. However^ it soon became evident that a chemical analj^sis of water for sanitary purposes differs essentially from any other kind of analysis which the chemist may be called upon to make. The find- ing of arsenic or some poisonous alkaloid in a suspected fluid is decisive, and a report on such finding is merely a statement of fact. In the analysis of water, on the other hand, the findings are purely relative and must be properly interpreted before they can be of any value. A drinking-water, to use the legal phraseology, is indicted on circumstantial evidence, and it depends on the erudition and ability of the chemist to so interpret and connect the evidence as to make out a clear case for or against the suspected water. The object of a chemical analysis of water is to discover wliether or not pollution with objectionable organic impurities has taken place. By "objectionable organic impurities" we understand those which are from human or animal sources and are capable of convey- ing the germs of disease. In other words, we look principally for fecal contamination, inasmuch as the germs of tj'phoid fever, cholera, .dysentery, and other intestinal disorders are excreted with the feces, and together with the feces gain access to the water. By itself, organic matter in the minute quantities in which it is present in water is not injurious to health, even if derived from sewage. It is only because this organic matter may be the carrier of disease germs that it becomes a matter for serious consideration. Therefore, organic matter derived from plants or vegetables removed from the possi- bility of infection with disease-producing bacteria has no significance from a sanitary standpoint, and its presence in drinking-water in no way renders it unwholesome. It is thus evident that the aim of the sanitary chemist is to dis- cover, first, the presence of organic matter which would indicate pollution, and, second, to determine the source of this organic matter. How well these two requirements are fulfilled by a chemical analysis will be made clear later. Dead organic matter in water, as elsewhere, is not in a state of stability. Through the agency of certain bacteria, in the presence of oxygen, it continuously undergoes material changes, becoming resolved into simpler inorganic compounds. The nitrogenous sub- stances are converted into ammonia, and the latter into nitrous and finally nitric acid, the two acids combining with bases usually present to form nitrites and nitrates, respectively. These changes may be best illustrated by the following scheme: — EXAMINATION OF WATER. 95 {Carbon — Carbon dioxide. Hydrogen f. . [^^|^!\^ f^^ | Nitric acid XT-+ i Ammonia -{ (Nitrites) >■ ,t.j-, , , Nitrogen \ \ Water J (^i^^'ates). This process, may it be remarked in passing, is a beneficial one, since by its means purification of polluted water is accomplished and the decaying organic matter converted into useful plant food. These changes, under favorable conditions, take p^ace incessantly so long as there is a supply of dead organic matter and the neces- sary bacteria are present. Therefore, the amount of organic matter in water represents that portion which has not yet undergone disin- tegration — the organic nitrogen or so-called albuminoid ammonia — as well as the various intermediary products of the portion which has undergone or is undergoing disintegration — free ammonia, nitrites and nitrates. The quantitative relation of these products of oxidation to each other as well as to the unoxidized nitrogenous matter will depend on the original amount of the organic matter and the rapidity with which oxidation has taken place. Therefore, an analysis which discloses these various stages of oxidation reveals also not only the presence but the retrogressive course of the organic matter. Given a water containing relatively large amounts of albu- minoid and free ammonia, together with nitrites and nitrates, the indications would be that such water contains a large amount of organic matter in a state of incomplete oxidation; in other words, the contamination is recent. On the other hand, the presence of nitrates, in the absence of nitrites, with only small amounts of free and albuminoid ammonia, would indicate complete oxidation or a previous pollution. It goes without saying that pure water should contain only traces of albuminoid and free ammonia and should be free from nitrites and nitrates, the latter, if in small quantity, being rapidly appropriated by the water-plants. It is to be expected that in deep wells removed from the possibility of pollution, the water will contain very slight amounts of ammonia and no nitrites or nitrates, or mere traces, although free ammonia may sometimes be present in large amounts as a result of oxidation of vegetable matter or nitrates by ferric oxide. In addition to organic matter, water contains various salts, the most important and constant of which is sodium chloride, or, occa- sionally, magnesium and calcium chloride. These chlorides are de- rived from the sea or geological formations rich in salts. The amount of chlorides will vary witb the natural source and remains 96 TEXT-BOOK OP HYGIENE. fairly constant. However, when the water is polluted with sewage or household refuse the chlorides will increase in proportion to the degree and nature of the pollution, and this increase serves as a reliable indication of past or present pollution. This index, how- ever, is of value only when the normal chlorine contents of the water in question or of waters in the immediate neighborhood are known. There are a number of serious objections to the data obtained by a chemical analysis, (1) Excessive free ammonia in ground-waters may be the result, as has been mentioned, of the oxidizing action of iron or other metals on the nitrates present, while in surface waters it may be produced by the action of a fungus Crenothrix (Brown). (2) The nitrites found in deep-well water may be the result of the reduction of nitrates normally present in the soil and, consequently, in no way represent organic pollution. One of the chief objections, however, is that a chemical analysis does not reveal the nature of the organic matter, whether of vegetable or animal origin. Admitting that a certain water contains an excess of organic matter, the ques- tion arises. Does this organic matter represent harmless vegetables or dangerous sewage? The chemist cannot answer this question with a certainty which would preclude a "reasonable doubt.'' Yet a water contaminated even with large amounts of vegetable matter, while not the best kind of water to drink, is nevertheless, free from danger. It is true, that if the ammonia on distillation is given off rapidly and the nitrites and chlorine are excessive, the indications that the organic matter is derived from sewage are reasonably clear, but the rapidity with which ammonia even from the animal matter is given off is only comparative and there is no way of gauging it, while a correct inter- pretation of the excessive amount of chlorine as compared with the normal chlorine standard of that particular locality presupposes a previous study of unpolluted waters which is seldom made and which often cannot be made. The other objection, one of a much more serious nature, is that water may be organically pure and yet contain germs of disease. Instances are cited by a number of authors showing that water- supplies pronounced on chemical evidence to be above suspicion have been proved to have caused serious epidemics of typhoid fever or dysentery. Thus Dr. Thresh, in his well-known book on "Water and Water-supplies," cites a number of such instances. The water from the river Ouse, below where it receives the sewage of Buckingham, to which an epidemic of typhoid fever was attrib- EXAMINATION OF WATER. 97 uted, was analyzed by the public analyst, who reported that it "does not appear from the analysis to contain sewage matter/' The Beverly water-supply, which became polluted with infected sewage from an asylum, giving rise to a typhoid epidemic, was pro- nounced by the chemist to be "of a very high degree of purity, and eminently suitable for drinking and domestic purposes." Analysis of water from the sewage-polluted Trent showed that "there is no evidence of the product of sewage contamination." The well-water supplying Houghton-le- Spring became contami- nated with sewage from a farm, causing a sudden outbreak of typhoid fever. The chemist who analyzed the water reported that "this water is very free from indications of organic impurity. . . . It is a good water for drinking purposes." The reason for this evident failure on the part* of the chemist to detect dangerous pollution is not difficult to find. A generally pure water may become contaminated with an amount of sewage too small to give evidence of its presence when diluted with several mil- lion gallons of water, yet this small amount of sewage may contain numerous specific germs the presence of which cannot be detected by a chemical analysis. Again, the sewage may have undergone com- plete oxidation and the end-products taken up by the plants, leaving no perceptible evidence of the pollution, while many of the specific germs which have been present in the original sewage remain viable and capable of causing disease. However, the employment of chemical analysis for comparing different waters in the same locality or a certain water at different times is of undoubted value. In this connection, the data obtained by a chemical analysis are both accurate and valuable. Also in the study of filtration, especially of the slow sand type, chemical analy- sis of the raw water and effluent made from time to time furnishes valuable evidence of the efficiency of the filter in removing turbidity and color, and bringing about the nitrification of organic matter which is the essential feature of this process of water-purification. Bacteriological Examination. — With the advent of bacteriology, and especially after the introductioii of Koch's plate method of iso- lation of bacteria, the hopes of the sanitarian had been revived. It was supposed that at last we have a method by means of which we may detect the specific causes of disease in water, and thus place the ex- amination of water on the same certain basis as the detection of poisons. With the knowledge that typhoid fever is usually caused by the drinking-water and after the discovery by Koch that cholera is 98 TEXT-BOOK OF HYGIENE. of similar origin, it was expected tliat the typhoid bacilli and the cholera spirilla could be detected in the suspected water. Unfortu- nately, disappointment followed all attempts in this direction. It soon became evident that while a certain water had been the cause of either a cholera or typhoid epidemic, as established by all evidence at hand, neither the cholera spirillum nor the typhoid bacillus could be detected in such waters. The cause for this failure was found in the great predominance of water bacteria which overgrow and obscure the few specific parasites, rendering their discovery impossible. The effort may be compared to looking for a needle in a haystack. While not entirely abandoned, the search for specific micro-organisms has not been made the object of routine examinations; and until some satisfactory method is devised by which the saproph3^tic bacteria may be entirely eliminated and the number of the specific micro-organisms increased so as to have them present in very small quantities of the water, the bacteriologist must depend upon other data upon which a conclusion as to the quality of the water may be reasonably based. It was thought for a time that the number of bacteria in the water could serve as an index of pollution, and a number of standards of bacterial purity have been suggested by various authors. Thus, Koch considers 100 bacteria per cubic centimetre as the safe limit for drink- ing-water; Miquel raises the standard to 1000; Crookshank agrees with this standard, while Mace and Migula claim that 250 to 500 bacteria is the highest limit for a good drinking-water. These or any other arbitrary standards based on mere number of bacteria are as fallacious as the "standards" proposed from time to time for ammo- nias, nitrites, nitrates, etc. The number of bacteria in water Avill vary greatly with the medium, the reaction of the medium, the length of time the colonies are allowed to develop, dilution, etc. And there- fore, number alone, while indicating the presence of organic matter, does not necessarily show that the water contains pathogenic germs. This fact can be more readily ascertained by determining the num- ber of bacteria which develop on bile-agar^® at body temperature and the presence or absence of bacillus coli. Dr. De Chaumont^^ classifies water under the four heads of Pure and Wholesome Water, Usable Water, Suspicious Water, and ^^ The bile-agar medium is prepared according to the following formula: — Agar 1-5 gms. Sodium taurocholate 5 " Peptone 2.0 " Water 100 c. c. This is prepared as xisual and 1 per cent, lactose added. "Parkes' Hygiene, vol. i, pp. 103-106. EXAMINATION OF WATER. 99 Impure Water. The characters of these waters are arranged in a series of tables, the essential details of which are given in Table XIV. Table XIV. Pure Usable 1 Suspicious Impure Water. Water. Water. Water. CHEMICAIj Constituents. I. II. ni. IV. Parts in 100,000. Parts in 100,000. Parts in 100,000. Parts in 100,000. Chlorine in solution . Under 1.4000 Under 4.2857 4-7 Above 7.1428 Solids " total . " 7.1428 " 42.8571 43-71 " 71.4285 " " volatile " 1.4000 " 4.2857 4-7 " 7.1428 Ammonia, free or sa- line " 0.0020 " 0.0050 0.0050-0.0100 " 0.0100 Ammonia, albuminoid " 0.0050 " 0.0100 0.0100-0.0125 " 0.0125 Nitric acid in nitrates " 0.0323 " 0.5000 0.5-1.0 " 1 0000 " " nitrites Nil. Nil. 0.0500 " 0.0500 Nitrogen in nitrates . " 0.0140- " 0.1129 0.1243-0.2373 " 2415 Total nitrogen . . . " 0.0230 " 0.1252 0.1255-0.2465 " 0.2601 Oxygen absorbed by permanganate and acid within half an hour at 140O F. . . " 0.0250 " 0.1000 0.1000-0.1500 " 0.1500 Total hardness . . . " 8.5 " 17.3 Above 17.0 " 28.5 Permanent hardness . " 3.0 " 5.7 " 5.7 " 8.7 Phosphoric acid in phosphates . . . Traces. Traces. Heavy traces. Heavy traces Sulphuric acid in sul- phates " Under 3.000 Above 3.000 Above 4.2857 Heavy metals . . . Nil. Traces. Traces. ( Any except \ iron. Hydrogen sulphide . " Nil. Nil. Present. Alkaline sulphides Physicat. Chaeacters. No. I. Colorless, or bluish tint; transparent, sparkling, and well aer- ated; no sediment visible to naked eye; no smell; taste palatable. No. II. Colorless, or slightly green- ish tint; transparent, sparkling, and well aerated ; no suspended matter, or else easily separated by coarse filtration or subsidence; no smell; taste palatable. No. III. Yellow, or strong, green color; turbid; suspended matter con- siderable; no smell, but very marked taste. No. IV. Color, yellow or brown; turbid, and not easily purified by coarse filtration ; large amount of susnfndf'd matter; very marked smell or taste. Microscopical Characters. No. I. Mineral matter ; vegetable forms with endochrome ; large animal forms, no organic debris. No. II. Same as No. I. No. HI. Vegetable and animal forms more or less pale and colorless; organic deiris; fibres of clothing, or other evidences of house-refuse. No. IV. Bacteria of any kind; fungi ; numerous vegetable and ani- mal forms of low types; epithelia, or other animal structures; evidences of sewage; ova of parasites, etc 100 TEXT-BOOK OF HYGIENE. Methods of Water Analysis. — Turbidity. — This may be de- termined either by the platinum wire method or by comparison of the sample with known quantities of silica suspended in water. The standard of turbidity adopted by the United States Geological Survey is "a water which contains 100 parts of silica per million in such a state of fineness that a bright platinum wire one millimetre in diam- eter can just be seen when the centre of the wire is 100 millimetres below the surface of the water^ and the eye of the observer is 1.2 metres above the wire. The observation being made in the middle of the day, in the open air, but not in sun-light, and in a vessel that the sides do not shut out the light so as to influence the results. The turbidity of such water shall be 100."-°. To carry out this method, a wooden rod 5 feet long and 1 inch square is taken and a small plati- num wire 1 millimetre in diameter inserted about 1 inch from the end. The rod is then graduated, the mark of 100 being placed at a distance of 100 millimetres from the centre of the wire. The inter- mediary graduations are made according to a table furnished by the United States Geological Survey (Circular No. 8, 1902). The mark on the rod at which the platinum wire vanishes is the turbidity in parts per million. The silica method, which is much more convenient, consists of a standard suspension of one gramme of dried diatoma- ceous earth in one litre of distilled water. This represents a turbidity of 1000 parts per million. From this stock suspension, standards for comparison are prepared by diluting certain quantities with distilled water. Thus 1 c. c. diluted with 100 c. c. of water equals a turbidity of 10 parts per million. The comparison is made in 100 c. c. Nessler tubes or glass-stoppered bottles. Significance. — Turbidity is objectionable from an esthetic stand- point, although highly turbid water may be entirely wholesome, and vice versa. However, no one likes to drink muddy water, and for this reason turbidity enters as an important factor in determining the quality of a given water or in deciding upon the desirability and methods of filtration. Color. — The color of a water is determined by comparing 100 c. c. of the sample with an equal quantity of a standard prepared from a solution containing 1.246 grams of potassium platinic chloride per litre. This solution has a color of 500. Significance. — Color in water has the same significance as tur- bidity, and unless due to organic or inorganic impurities such as -"Report of Committee on Standard Methods of Water Analysis, Amer- ican Public Health Association, 1905. EXAMINATION OF WATER. 101 sewage or dyes, has no effect on the quality of the water from a purely hygienic standpoint. Odor. — The odor is determined by violently shaking a bottle half full of the sample and then smelling it. The odor generated by heat- ing is determined as follows :" About 150 c. c. of the sample are poured ii^to a 400 c.c. beaker. The beaker is covered, placed on a hot plate, and heated to just below boiling. The beaker is then shaken and the odor detected by the smell. Significance. — The odor of water may indicate its source as well as the presence of sewage. Objectionable odors, however, may be caused by certain micro-organisms. Thus, a "fisliy" odor is caused by Uroglena, an "aromatic" or "rose geranium" odor by Asterionella, and a "pig-pen" odor by Anabena. A very disagreeable odor is caused also by Crenothrix. Total Solids. — This is determined by evaporating 100 c.c. of the water in a weighed platinum dish, drying the residue in an oven at 105° C. for thirty minutes, and then weighing. The weight of the residue in milligrams equals parts per million. Organic Nitrogen. — The presence and amount of organic nitro- gen in a given water are determined as free ammonia, albuminoid am- monia, nitrites, and nitrates. These substances represent the various stages of decomposition which organic nitrogen undergoes in its transformation from a complex to a simple compound. Free Ammonia. — This is determined by distilling 500 c. c. of the sample in a flask connected with a condenser. The distillate is col- lected in glass cylinders (INTessler tubes) and a small amount of ISTessler reagent-^ added and the distillate compared with standards prepared by adding definite quantities of ammonium chloride to pure water. As a rule 150 c. c. of the first distillate contain all of the free ammonia. Albuminoid Ammonia. — After the free ammonia is distilled off, the distillation is interrupted and 50 c. c of an alkaline solution of potassium permanganate-^ added. The distillation is resumed and carried on until four or five Nessler tubes are collected. The distil- late in each tube is then treated as above. Nitrites. — One hundred c. c. of the sample are decolorized, if ^ This reagent reacts with minute quantities of ammonia. It is made by dissolvinfi: .50 gnis. of potassium iodide in water and adding a saturated solution of mercuric chloride, enough to produce a permanent precipitate. 400 f. c. of a .50-per-cent. solution of potassium hydrate are added, and the whole dilutefl to one litre. ^^ This is prepared by dissolving 200 gms. of potassium hydroxide and 8 gms. of potassium permanganate in a litre of distilled water. 102 TEXT-BOOK OF HYGIENE. necessary, with aluminum hydrate and poured into a 100 c. c. Nessler tube. To this are added 1 c. c. of sulphanilic acid solution ( 8 grammes of sulphanalic acid in 1000 c. c. of dilute acetic acid, specific gravity l.O-i) and 1 c. c. naphthylamine solution (5 grammes of naphthylamine in 1000 c. c. of dilute acetic acid). The tube is cov- ered, allowed to stand for ten minutes, and the resulting pink color compared with standards containing definite amounts of sodium nitrite in solution, the standards having been' treated in the same manner as the sample. Nitrates. — Twenty c. c. or less of the sample are evaporated on a water-bath and the residue treated with 1 c. c. of phenolsulphonic acid (phenol, 30 grammes; concentrated sulphuric acid, 370 grammes) . About 10 c. c. of water are added and enough ammonia to render the liquid alkaline. The liquid is then transferred to a 100 c. c. ISTessler tube, distilled water added to the 100 c. c. mark, and the yellow color matched with standards containing definite amounts of potassium nitrate, and -treated as above. Significance. — With the exception of deep waters, which may contain large amounts of nitrogen as free ammonia (due to reduction of nitrates) and still be pure, the presence of excessive quantities of organic nitrogen indicates pollution. An excess of free ammonia (above 0.06 parts per million), especially if nitrites are present, points to recent pollution, while an excess of nitrates (above .2 parts per million for surface-waters and 2 parts per million for ground- waters) points to past pollution. As to albuminoid ammonia, Wank- lyn holds that if the water contains aKove 0.10 per million it begins to be very suspicious, and if over 0.15 parts per million, it should be condemned absolutely. This standard is regarded by Mason as too rigorous. Oxygen Consumed. — One hundred c. c. of the sample are meas- ured into a flask, 10 c. c. of dilute sulphuric acid^"^ and 10 c. c. of solution of potassium permanganate^* added; the flask is then placed in a bath of boiling water and kept there for exactly thirty minutes. At the end of that period, the flask is removed, 10 c. c. of ammonium oxalate solution-^ added, and the clear fluid titrated Avith the stand- ard permanganate solution until a faint but distinct color is obtained. ^' One part of sulphuric acid to 3 parts of distilled water. ^* This standard solution contains 0.4 gm. of potassium permanganate in one litre of distilled water. ^ This solution contains 0.888 gm. of ammonium oxalate in one litre. One c. c. of this solution should neutralize one c. c. of the permanganate. EXAMINATION OF WATER. 103 Each cubic centimetre of the standard permanganate in excess of the oxalate solution rejDresents 0.0001 gram of oxygen consumed by the sample. This, multiplied by 10, equals parts per million. Significance. — This determination indicates the presence of or- ganic carbon. If the oxygen required is high and the ammonias ex- cessive, the indications are that the pollution is of vegetable origin; while if the ammonias are high and the oxygen required low, the pol- lution is in all probability animal in character. Chlorine. — Solutions required: 1. Standard silver-nitrate solu- tion. To 1 litre of pure distilled water add 4.788 grammes of pure silver nitrate (AgNOj). One cubic centimetre of this solution is equivalent to 1 milligramme of chlorine. 2. Potassium-chromate solu- tion. A 10-per-cent. solution of potassium chromate (KoCrO^) in dis- tilled water free from chlorine. Process : To 100 c. c. of the water to be tested add a few drops of the potassium-chromate solution, and then run in the silver-nitrate solution from a graduated burette, adding it drop by drop and stirring the water continually with a glass rod. Continue until a faint but permanent orange-red tint has been produced, showing that all the chlorine has been combined with the silver, the persisting reddish tint being due to silver chromate. The number of cubic centimetres of silver-nitrate solution used indicate the number of milligrammes of chlorine in 100 c. c. of the water, or the parts per 100,000 ; this multi- plied by 10 gives the number of milligrammes of chlorine in 1 litre, or parts per million. If the water contain but little chlorine, the test will be more accurate if 250 c. c. of the water be first evaporated over a water-bath to about 50 c. c. before proceeding as above : four times the result will then give the number of milligrammes of chlorine in 1 litre. Should it be desired to express the proportion in terms of sodium chloride, multiply the result, obtained as above, by 1.648; or make up the silver-nitrate solution by adding 2.905 grammes to the litre, each cubic centimetre of this solution being then equal to 1 milli- gramme of sodium chloride. Significance. — Chlorine, or its compounds, when present in drinking-water, indicates generally sewage pollution. It is true that chlorine may be in excess in water, and the latter, nevertheless, be entirely free from sewage or urine, but this occurs only where there is a natural deposit of chlorine compound in the soil from which the sup- ply is drawn. If communication with the sea or salt-deposits is exclnclcd, the chlorine may be assumed to be due to the inflow of sewage. 104 TEXT-BOOK OF HYGIENE. Hardness. — Solutions required: 1. Soap solution. Dissolve about 10 grammes of Castile or soft soap in 1 litre of weak (35 per cent.) alcohol. 3. Standard lime solution. Dissolve 1.11 grammes pure calcium chloride in 1 litre of distilled water. One cubic centi- metre of this solution is equivalent to 1 m. g. of calcium carbonate (CaCOg). Process: Firsts find how much of the soap solution is needed to make a lather with 100 c. c. of distilled water, as follows : Place the water in a flask holding about 250 c. c. and run in the soap solution from a burette, a few drops at a time, corking and shak- ing the flask well after each addition. The lather should have a depth of about one-fourth of an inch, and should be permanent for at least five minutes. Then standardize the soap solution by diluting 5 c. c. of the standard lime solution to 100 c. c. with distilled water and find- ing how many cubic centimetres of the soap solution are necessary to make a permanent lather with it. This quantity, less the number of cubic centimetres needed to make a lather with the 100 c. c. of dis- tilled water, represents the amount of soap solution that will neutral- ize 5 m. g. of calcium carbonate or its equivalent. Lastly, determine in the same way the number of cubic centimetres of soap solution necessary to make a permanent lather with 100 c. c. of the water to be examined; subtract the quantity necessary for 100 c. c. distilled water and estimate the amount of calcium carbonate or its equivalents pres- ent, as follows : For example, it takes 2 c. c. of soap solution to make a lather with the distilled water and 12 c. c. with the diluted lime solution. Then, 12 — 2 = 10 c. c. = 5 m. g. calcium carbonate, and each cubic centimetre of the soap solution = 0.5 c. c. of the standard lime solution, or 0.5 m. g. calcium carl)onate. Consequently, if 100 c. c. of the water examined require 17 c. c. of soap solution, it must contain (17 — 2) X 0.5 = 7.5 m. g. calcium carbonate or its equiva- lent, and 1 litre of the water contains 75 m. g. calcium carbonate. Lead, Copper, and Iron. — To 50 or 100 c. c. of the water in a white porcelain dish, or in a tall glass jar, over white paper, add a few drops of ammonium sulphide, — (NH^)2S. A dark coloration or precipitate indicates the presence of either lead, copper, or iron, due to the formation of the respective sulphide. Then add a few drops of hydrochloric acid (HCl). If the color disappear, iron only is pres- ent; if it persist, lead or copper is present. In the latter case, add a few drops of acetic acid and about 1 c. c. of a strong solution of pure potassium cyanide. If the color disappear, it is due to copper; if it remain, lead is present. If lead only is present in the water, the above test will detect ^/^p grain per gallon, The above test may be EXAMINATION OP WATER. 105 corroborated as follows : Partly fill two test-tubes with the original water; to one add a little potassium-chromate solution; an opacity and the deepening of the color to a canary yellow indicates lead. To the second add a drop of dilute hydrochloric acid and a few drops of potassium-ferrocyanide solution; a blue color indicates iron, either ferrous or ferric ; a bronze or a mahogany-red color indicates copper. Quantitative tests for the above metals may be made by making standard solutions of the respective elements, treating a measured quantity of the original water with the proper reagejit, as indicated, and comparing the color produced with that given by a definite quan- tity of the respective standard solution. Phosphates. — Solution required, ammonium molybdate: Dis- solve 10 grammes of molybdic anhydride in 41.7 c. c, of ammonia (NH^HO), — sp. gr. 0.96, — and pour slowly into 125 c. c. of nitric acid (HISrOg), — sp. gr. 1.20; allow to stand in a warm place for sev- eral days till clear. Process : slightly acidify 500 c. c. of the water with nitric acid, evaporate to about 50 c. c, add a few drops of ferric chloride (FcaClo) and ammonia in slight excess. Filter, dissolve the precipitate in the smallest possible quantity of nitric acid, and evap- orate to 5 c. c. Heat nearly to boiling ; add 2 c. c. of ammonium- molj^bdate solution; keep solution warm for one-half hour. If there is an appreciable quantity of precipitate, collect it on a small, weighed filter-paper, wash with distilled water, dry at 100° F., and weigh. The weight of the precipitate multiplied by 0.05 gives the amount of phosphates as PO4 in the 500 c. c. of water. Bacteriological Examination. — The following method of proced- ure has been recommended by the committee on laboratory methods of the American Public Health Association: — Media. — The standard medium for determining the number of bacteria in water shall be nutrient gelatin, and for polluted waters which cannot be plated promptly after collection agar may be substi- tuted. All variations from these two media shall be considered as special media. If any medium other than standard gelatin is used, this fact shall be stated in the report. For general work the standard reaction shall be 1 per cent, acid, but for long-continued work upon water from the same source the optimum reaction shall be ascertained by experiment and thereafter adhered to. If the reaction used, how- ever, is different from the stanclard, it shall be so stated in the report. Procedure.— Shake at least twenty-five times the bottle which contains the sample. Withdraw 1 e. c. of the sample with a sterilized pipette and deliver it into a sterilized Petri dish 10 centimetres in 106 TEXT-BOOK OF HYGIENE. diameter. If there is reason to suspect that the number of bacteria is more than 200 per cubic centimetre, mix 1 c. c. of the sample with 9 c. c. of sterilized tap or distilled water, and so on. Shake twenty- five times and measure 1 c. c. of the diluted sample to a Petri dish. If a higher dilution is required, proceed in the same manner, e.g., 1 c. c. of the sample to 99 c. c. of sterilized water, or 1 c. c. of the once diluted sample to 99 c. c. of sterilized water, and so on. In the case of an unknown water it is advisable to use several different dilutions for the same sample. To the liquid in the Petri dish add 10 c. c. of standard gelatin at a temperature of about 30° C, or 10 c. c. standard agar at a temperature of about 40° C. Mix the medium and water thoroughly by tipping the dish back and forth, and spread the con- tents equally over the bottom of the plate. Allow the gelatin to cool rapidly on a horizontal surface and transfer to the 20° C. incubator as soon as it is hard. Incubate the culture for forty-eight hours at a temperature of 20°C. in a dark, well-ventilated incubator where the atmosphere is practically saturated with moisture. After this period of incubation place the Petri dish on a glass plate suitably ruled, and count the colonies with the aid of a lens which magnifies at least five diameters. So far as practicable, the number of colonies upon the plate shall not be allowed to exceed 200. The whole number of col- onies upon the plate shall be counted, the practice of counting a fractional part being resorted to only in case of necessity. When agar is used for plating, it will be found advantageous to use Petri dishes with porous earthenware covers in order to avoid the spreading of colonies by the water of condensation. For the detection of B. coll and other specific bacteria consult text-book on bacteriology. QUESTIONS TO CHAPTER II. WATER. For what purposes do people need water? Why should the supply be pure? What is the quantity needed by each person daily, and what quantity should be supplied per head in towns and cities for all purposes? How may waste of water be prevented? What is the objection to the use of water- meters ? What is the original source of all fresh water? How is rain-water usually collected and stored? What are the objections to underground cisterns? What is the only material of which underground cisterns should be made? From what source do most cities and towns derive their water-supply? What precautions must be observed regarding such a source? What arc some of the minor objections to the use of river-water? What peculiar diseases may be due to such water? What is the most serious objection to the use of river-water for domestic purposes? How does a running stream purify itself? Can this self -purification be relied upon? Can it be stated definitely when a stream once polluted becomes fit for use again? Is it safe to use water from a stream known to have been contaminated by sewage? What is usually the quality of water from fresh-water lakes and ponds? What large city uses lake- water entirely? What precautions must be observed regarding such a source of supply? To what is the off'ensive taste and odor of water from small lakes or storage-reservoirs often due? Does water purify itself absolutely in freezing? What matters may be found in ice? Are all pathogenic micro-organisms destroyed by freezing? What part of ice is the purest ? What class of peisons usually derive their drinking-water from springs and wells? What is the relative purity of spring- and of well-water? Why? What changes take place in diluted organic matter in percolating through the soil? To what are these changes due? What may retard or check these changes? Is water containing nitrites and nitrates necessarily dangerous? Of what are nitrites and nitrates an indication? Name some of the qualities that are desirable in water for drinking or domestic purposes. When is a water said to be hard? To what is the hardness of water due? What is the distinction between "removable" or "temporary" and "permanent" hardness, and what is meant by "total" hardness? How is the degree of hardness determined, and upon what does the test depend? Describe the test. Why is hard water objection- able for domestic use? (107) 108 TEXT-BOOK OF HYGIENE. What diseases and derangements of health maj' be due to hard water? Is the evidence absolute regarding all of these? What troubles may large amounts of suspended mineral matter cause? How may such water be clari- fied? What mineral in the water is essential to the process? What may be the effect of large quantities of organic matter in the water? What infectious diseases may be due to impure drinking-water? What other organisms hannful to health, other than bacteria, may be found in drink- ing-water? Name some notable places where epidemics have been undoubt- edly caused by impure drinking-water. How may a milk-supply be infected by impure water? How might a water be polluted in distribution, even though the source be pure? What is the advantage of a prolonged storage of river-water? What waters should not be stored in lead-lined cisterns or conveyed in leaden pipes? What is the greatest amount of lead permissible in water? In what ways may water be purified on a large scale ? Explain the process of sand filtration. Wliat methods may be used in the household for the purification of water? How may the water be softened? How may disease germs and other organisms in water be destroyed? How may organic matter be removed? What are some good filtering materials? ^^^lat are some of the essential requisites of a good house-filter? What is necessary that every house-filter may be safe for use? Are any filters absolutely germ-proof? How are the color, transparency, and odor of water determined, and what is the standard of comparison? Is a turbid or colored water necessarily harmful, and may a perfectly-clear water be dangerous to use? How are the total solids of a water determined quantitatively? Describe the permanganate-of-potash test for the deteniiination of the organic matter in water. What does an excess of chlorine or chlorides in water generally indicate, and why? How may these be determined quantitatively? If sewage contamination of a water be suspected, how may the suspicion be confirmed? Why should the presence of nitrites or nitrates in water excite the suspicion of sewage contamination. Give a test fOr each. By what reagent is the presence of ammonia determined? How may we know whether an excess of chloi'ides is due to sewage con- tamination or not? What is the probable source of ammonia if in excess and in company with nitrates, etc. ? Which is supposed to indicate the most recent contamination, nitrites or nitrates? What does the presence of nitrates with- out nitrites or ammonia indicate? What lime-salt is most readily removed by boiling? What relation has the organic matter to the nitric acid? Into what four classes may water be divided? Name some of the char- acteristics of these different classes. What are the solutions needed in the quantitative test for chlorine? What is the strength of each, and what is the relation of the silver-nitrate solution to chlorine? What is the use of the potassium-chromate solution? QUESTIONS TO CHAPTER II. 109 How may the result be expressed? What solutions are used in testing for nitrates quantitatively? In testing for hardness, why is a standard lime solution necessary ? Wliat should be the characteristics of the lather produced by the soap solution? Why is alcohol used as a solvent for the soap? What is the underlying prin- ciple of this test? How may lead, copper, or iron be detected in water? How may you distinguish between the respective sulphides of the above metals? How may the above test respecting any one of the metals be corroborated? How deli- cate is the test, as regards lead? How might a quantitative determination of these metals be made? What is the principal reagent used in the test for phosphates? How may a bacteriological examination of water be made? What pre- cautions must always be observed in such examinations? CHAPTER III. FOOD. In order to preserve health and vigor it is necessary for animal beings to consume at intervals a sufficient quantity of substances known as food. Alimentary substances, or foods, may, therefore, be briefly defined as materials which, taken into the body and assim- ilated, sustain the processes of life, promote growth, or prevent de- struction of the organized constituents of the body. According to Atwater,^ a food is a "material which, when taken into the body, serves to either form tissue or yield energy, or both." This definition includes all the ordinary food-materials, since they build tissue as well as yield energy ; but it excludes creatin, creatinin, and other so-called meat-extractives and likewise thein or caffein of tea and coffee, as they neither build tissue nor yield energy. QUANTITY AND CHARACTER OF FOOD NECESSARY. It has long been known, as the result of the empirical observa- tion of feeding large bodies of people, that the various proximate principles composing the tissues must be combined in certain definite proportions in the food in order to preserve the normal degree of health and vigor of the body. Within a comparatively recent period physiologists have made experiments upon animals and liuman beings which have led to the same conclusions, and have enabled these pro- portions to be fixed with more or less exactness. Considering man as an omniverous animal, it may be laid down as an invariable rule that the following four alimentary principles are necessary to his existence.^ ISTeither of these principles can be dispensed with for a prolonged period without illness or death re- sulting. 1. Water. — This must be supplied in sufficient quantity to permit the interchange of tissue to be carried on in the body. 2. Salts. — Inorganic compounds of various kinds are necessary to the preservation and proper construction of the tissues. They are all found in sufficient quantities in the various alimentary substances ^U. S. Department of Agriculture, Bui. No. 21. ^ Physiologie, Landois, 2te Aufl., p. 448. (110) QUANTITY AND CHARACTER OF FOOD NECESSARY. Ill consumed by man and the lower animals. A deficiency of inorganic constituents in the food is followed by disease, 3. Proteids. — Organic nitrogenous material, either animal or vegetable, is a necessary constituent of the food of man. Continued existence is impossible without a sufficient supply of nitrogenous substances. 4. Fats or Carbohydrates. — The organic non-nitrogenous or car- bonaceous principles of food are also necessary to the continuance of health. They are supplied either by fats or by carbohydrates (sugar, starch, etc.), which may, within certain limits, be used as substitutes for each other. Voit has shown that 17 parts by weight, of starch, are equivalent as carbonaceous or oxidizable food to 10 parts of fat. The physiology of nutrition has been very carefully studied by a large number of experimental physiologists, who have arrived at conclusions differing widely from those generally accepted by the older writers on the subject. The division of foods into plastic and respiratory foods, or, in a general way, into proteids, or muscle- builders, and fats and carbohydrates, or oxidizing foods, is now no longer recognized in science. It has been established that proteid tis- sues are not alone the result of proteid food, and that the accumula- tion of fat in the body is not altogether due to the excessive con- sumption of fats and carbohydrates. It has been further shown, con- trary to the general belief, that the nitrogenous or proteid tissues are not used up during hard labor any faster than when at perfect rest, but that, on the contrary, increased muscular exertion is attended by increased consumption of stored-up fat. These facts have led to a modification of the standard dietaries formerly employed. At present the standards of the quantity of food principles required to maintain equality between bodily income and expenditure are those calculated by Professor Yoit, and Professor Atwater in this country, after many experiments upon human beings and the lower animals. These standards are as follow: — . Table XV. ADULT MALE OF AVERAGE WEIGHT. At Rest. Moderate Labor. Severe Labor. Proteids .... Fats Carbohydrates . . 110 grammes 50 " 450 " 118 grammes 50 " 500 " 145 grammes 100 " 500 " 112 TEXT-BOOK OF HYGIENE. Table XVI. Comparative Cost of Digestible Nutrients and Energy in Different Food Materials of Average Prices.^ [It is estimated that a man at light to moderate muscular work requires ahout 0.23 pounds of protein and 3,050 calories of energy per day.] Kind of Food Material Beef, sirloin Beef, sirloin Beef, sirloin Beef, round Beef, round Beef, round Beef, shoulder clod ..... Beef, shoulder clod Beef, stew meat ....... Beet, dried, chipped Mutton Chops, loin Mutton, leg Mutton, leg Roast pork, loin Pork, smoked ham Pork, smoked ham Pork, fat salt Codfish, dressed, fresh .... Halibut, fresh Cod, salt Mackerel, salt, dressed . . . Salmon, canned Oysters, solids, 50 cts. per qt. Oysters, solids, 35 cts. per qt. Lobster, canned Butter Butter Butter Eggs, 36 cents per dozen . . . Eggs, 24 cents per dozen . . . Eggs, 12 cents per dozen . . Cheese ..... Milk, 7 cents per quart . . . . Milk, 6 cents per quart . . . . Wheat flour Wheat flour Corn meal, granular . . . . Wheat breakfast food .... Oat breakfast food Oatmeal Rice Wheat bread Wheat bread Wheat breai Rye bread Beans, white, dried Cabbage Celery Corn, canned Potatoes, 90 cents per bushel . Potatoes, 60 cents per bushel . Potatoes, 45 cents per bushel . Turnips Apples Bananas Oranges .... . . . . Strawberries Sugar Cents 25 20 15 16 14 12 12 9 5 25 16 20 16 12 22 18 12 10 18 7 10 12 25 18 18 20 25 30 24 16 8 16 3^ 3 8 6 5 4 5 5 5 10 1 v^ 6 7 6 " a ■"0.5 o a Amounts foe 10 Cents Pounds 0,40 .50 .67 .63 .71 .83 .83 1.11 2 .40 .63 .50 .63 .83 .45 .56 .83 1 .56 1.43 1 .83 .40 .56 .56 .50 .40 .33 .42 .63 1.25 .63 2.85 3.33 3.33 4 4 1.33 1.33 2.50 1,25 1.67 2 2.50 2 2 4 2 1 6. 7 10 13.33 10 6.67 1.43 1.67 1.43 1,67 Pound 0.06 .08 .10 .11 .13 .15 .13 .18 .29 .10 .08 .07 .09 .11 .06 .08 .02 .11 .08 .22 !]3 .18 .02 .03 .10 .01 .05 .07 .14 .16 .09 .11 .32 .39 .31 .13 il9 .34 .08 .13 .16 .20 .15 .35 .05 M .02 .10 .15 .20 .08 .02 .01 .01 .01 Pound 0.06 .08 .11 .08 .09 .10 .08 .10 .23 .03 .17 .07 .09 .19 .14 .18 .68 ",02 .01 .20 .10 ','oi' .01 .40 .32 .27 .04 ,06 .11 .20 .11 .13 .03 04 .07 .02 .09 .16 '.02 .02 .03 .01 .03 .01 VoV .01 .01 .01 .01 .02 .01 W Pounds .01 .02 .02 .14 .17 2 45 2.94 2 96 .98 .86 1.66 .97 .87 1.04 1.30 104 1.16 .18 .05 .18 .93 1.40 1 87 .54 .65 .18 .13 .00 1.67 Calories 410 515 685 560 630 740 595 795 1,530 315 890 445 560 1,035 735 915 2,950 230 262 465 1,135 760 90 125 225 1,705 1,365 1,125 260 385 770 1,185 885 ■ 1 030 5,440 6,540 6,540 2,235 2,395 4,500 2.025 2,000 2,400 3,000 2,340 3,040 46') 130 430 1,970 2,950 3,935 1,200 1,270 370 250 215 2,920 sPrinciples of Nutiition and Nutritive Value of I'ood. By W. 0. Atwater. U. S. Dept. Agr. Bull. Ko. 142. ^The cost of 1 pound of protein means the cost of enough of the given material to furnish 1 pound of protein, without regard to the amounts of the other nutrients present. Likewise the cdst of energy means the cost of enough material to furnish 1,000 calories without reference to the kinds and proportions of nutrients in which the energy is supplied. These estimates of the cost of protein and energy are thus incorrect in that neither give^ credit for the value of the other. QUANTITY AND CHARACTER OF FOOD NECESSARY. 113 As the average weight of women is less than that of men, a re- duction of from 15 to 20 per cent, in the various food principles may be made for the female ration. The relative proportion of nitrogenous to non-nitrogenous prin- ciples in this ration is about 1 to 5. In the older diet standards, e.g., Moleschott's, the proportion of nitrogenous to non-nitrogenous prin- ciples is much larger, being, for a man at moderate labor, proteids, 130 grammes; fats, 84 grammes; and carbohydrates, 404 grammes, or about 1 to 3.75. While from ignorance, or motives of economy, many men sustain life and preserve health at hard labor on rations varying considerably from the standard above given, it is probable that, all things being considered, the most perfect physiological ration would also be the most economical. Thus, Professor Vaughn proposes a daily ration consisting of bread, cod-fish, lard, potatoes, bacon, beans, milk, sugar, and tea in such proportions as to furnish 123 grammes proteids, 70 grammes fats, and 550 grammes carbohydrates. The total cost or money value of this ration at present prices is about thirteen cents. In actual food value it is not inferior to the daily fare of the habitue of Delmonico's. (See Table XVI.) In estimating the food requirements of the organism, account is taken of the fact that the body takes in potential energy in the form of food and generates kinetic energy in the form of heat and motion. "Heat and muscular power are forms of force or energy. The energy latent in the food is developed as the food is consumed in the body. The process is more or less akin to that which takes place when coal is burned in the furnace of the locomotive. For the burning of the food in the body or the coal in the furnace, air is used to supply oxygen. When the fuel is oxidized, be it meat or wood, bread or coal, the latent energy becomes active, or, in technical language, the poten- tial energy becomes kinetic; it is transformed into heat and power. As various kinds of coal differ in the amount of heat given off per ton, so various kinds of food and food ingredients give off different amounts of energy; that is, have different values as fuel in the body."° The unit of measurement of the fuel-valve of food is a calorie, which is the amount of heat required to warm one gramme of water one degree centigrade. One calorie is equal to about 1.54 foot-tons; in other words, one calorie, when transformed into mechanical power, would lift one ton 1.54 feet. "Atwater. U. S. Department of Agriculture, Bull. No. 142. 114 TEXT-BOOK OF HYGIENE. Table XVII. Standard Dietaries {Hutchison). For a man at moderate muscular work. Food Materials Amount Proteids Fats Carbo- hydrates Fuel Value I. Beef, round steak Ounces 13 3 . 6 22 • Pounds 0.14 6.02 12 Pounds 0.12 0.16 6.02 Pounds 6^15' 0.75 Calories 695 Batter 680 Potatoes 320 Bread 1760. 44 0.28 0.30 0.90 3455 II. Pork, salt 4 2 16 8 6^23 0.04 0.21 0.11 0.02 0.01 ' 6.59 ' 0.28 880 - Butter 450 Beans 1615 IBread 640 30 0.27 0.35 87 3585 III. Beef, neck 16 16 4 16 3 0.10 ' \)M ' 0.02 0.04 0.09 0.09 05 0.04 '6.02' 0.02 0.05 0.15 0.17 0.56 0.19 550 Butter 225 Milk, one pint 325 Potatoes 320 Oatmeal 460 Bread 1280 Sugar 345 66 0.29 0.22 1.12 3505 IV. Beef, upper shoulder Ham 10 6 3 2 16 12 9 1 0.09 0.06 0.03 '6!u4" 0.01 05 0.13 0.13 0.02 0.11 0.04 '6.'6i' '6.05" 0.11 0.38 0.06 800 650 Eggs, two 135 Butter 450 Milk, one pint 325 Potatoes 240 Flour 825 Sugar 115 59 0.28 0.44 0.60 3540 QUANTITY AND CHARACTER OF FOOD NECESSARY. 115 Table XVII— (Continued). Standard Dietaries {Hutchison. ) For a man at moderate muscular work. Food Materials Amouut Proteids Fats. Carbo- hydrates Fuel Value V. Sausage Ounces 4 14 2 16 5 2 16 9 3 Pounds 0.03 0.07 'o"64' 0.07 0.01 0.01. 0.04 Pounds 0.11 'b!ii' 0.04 0.01 'o.'oi' Pounds "0A)5 0.18 0.10 23 0.28 0.19 Calories 510 Codfish 140 Butter 450 Milk, one pint 325 Beans 505 Rice 205 Potatoes 420 Bread 640 Sugar 345 71 0.27 0.28 1.03 3540 VI. Beef 8 4 3 2.^ 1 16 8 ■ 2 9 0.08 0.04 0.03 "0.62 0.04 001 0.01 0.05 0.10 0.04 0.02 0.13 02 0.04 o.oi' 0.65" 0.08 0.10 0.32 09 560 Mackerel, salt 230 Eo;gs, two 135 Butter 565 Cheese 130 Milk, one pint 325 160 Rice 205 720 Sugar 175 55 0.28 0.36 0.64 3205 The caloric value of the different food-stuffs has been estimated by Atwater as follows : — Protein, fuel value, 4.1 calories per gram, or 1859 calories per pound. Fats, fuel value, 9.3 calories per gram, or 4218 calories per pound. Carbohydrates, fuel value, 4.1 calories per gram, or 1859 calories per pound. To calculate the caloric value of any food, multiply the number of grammes of proteins by 4.1, the number of grammes of fat by 9.3^ and the number of grammes of carbohydrates by 4.1. An ideal ration, suggested by Mrs. E. H. Eichards, consists of proteids, 106.80 grammes; fats, 57.97 grammes, and carbohydrates, 389.80 grammes. On the other hand, Professor Chittenden, of Yale, maintained himself for nine months in an excellent physical condi- tion and ill perfect nitrogenous eciuililjrium on a ration which con- 116 TEXT-BOOK OF HYGIENE. sisted of about one-tliird the usual requirement of proteids, Avhile the total daily fuel-value of his diet was only about one-half the usual requirement. He also experimented on a group of thirteen volun- teers from the Hospital Corps, United States Army. They ranged in age from 21 to 43 years, and were of different nationalities. These men did average work, engaging daily in gymnastics and other physical labor. Their daily menu, with slight variations, was about as follows : — Breakfast. — Boiled hominy, 150 grammes; milk, 125 grammes; sugar, 30 grammes; butter, 10 grammes; bread, 30 grammes; cof- fee, one cup. Dinner. — Split pea soup (thick), 200 grammes; bread, 75 grammes; mashed potatoes, 100 grammes; pickles, 30 grammes; coffee, one cup; pie, 120 grammes. Supper. — Suet-pudding, 150 grammes; apple-sauce, 125 grammes; crackers, 25 grammes; tea, one cup. Total nitrogen, 7.412 grammes. Fuel value, 2000 calories. On this diet, poor in nitrogen, these men lived for six months, and at the end of the experiment were in a better "physicifil condition than when they commenced. A group of eight young college athletes were kept for five months on a diet equally poor in proteids, with the result that they gained in strength. What has thus far been said about the ingredients of food and the ways they are used in the body may be briefly summarized in the following schematic manner (Atwater) : — Nutritive ingredients (or nutrients) of food. Water. f Edible portion < I e.g., flesh of meat, t:, 3 1 J yolk and white of etc. Nutrients contains — Protein. Fats. Carbohydrates Mineral matters. 1^ Refuse. e.g., boneSj entrails^ shells, bran, etc. QUANTITY AND CHARACTER OF FOOD NECESSARY. 117 Uses of nutrients in the body. Protein Forms tissue e.g., white (albumen) of eggs, curd (casein) of milk, lean meat, gluten of wheat, etc. All serve as fuel to yield energy in the forms of heat and muscular power. Fats Are stored as fat e.g., fat of meat, butter, olive oil, oils of corn and wheat, etc. Carbohydrates Are transformed into fat. e.g., sugar, starch, etc. Mineral matters ( ash ) . . Share in forming bone, assist in digestion, etc. e.g., phosphates of lime, potash, soda, etc. In addition to maintaining a proper proportion between the various alimentary principles, it is necessary to vary the articles of food themselves, otherwise they are liable to prove nauseating. The necessity of variety in the food, in order to preserve the appetite, is familiar to every one. If a man wished to live on beef alone he would be obliged to eat about 2 kilogrammes per day in order to get a sufficient amount of non-nitrogenous food. Of potatoes, in order to get enough nitro- genous food, he would have to eat 8 kilogrammes. No human stomach could prove equal to the task of digesting this excess of material. On the other hand, it is to be noted how perfect the combination of the various principles is in human milk. In cow's milk, which is nearest in composition to human milk, the non-nitrogenous principles are deficient. Hence, the important practical point that when ordering milk diet for a patient a small portion of carbonaceous food (bread, rice, or sugar) must be added if the standard of health shall be reached or maintained. Climate has probably very little influence upon the amount of food required by the individual. The actual quantity of food con- sumed varies little between various races or in different parts of the earth. It is true, however, that a larger proportion of fat is required in cold climates. That fatty articles of food readily undergo oxi- dation and furnish a large amount of animal heat is proven both by observation and experiment. The albuminoid proximate principles of the food, proteids, are represented by the nitrogenous constituents of organic tissues. These are the vitellin and albumin of eggs, albumin, fibrin, globulin, myosin, syntonin, and other nitrogcnized principles of flesh and blood; the 118 TEXT-BOOK OF HYGIENE. casein of milk, the gluten, fibrin, and legmnin of cereal and legumin- ous seeds and plants, gelatin, and cliondrin. Fat constitutes an integral component of animal tissue, and is found in abundance as a constituent of nerve-tissue, marrow, and subcutaneous connective tissue. In food it is represented especially in the fatty tissue of meat, the yelk of eggs, butter, etc. The carbohydrates are represented especially by various products of the vegetable world, as sugar, -starch, dextrin, etc. Water and various other inorganic proximate principles, chief among which are compounds of calcium, sodium, and potassium, are usually found in sufficient proportion in the other alimentary sub- stances. The food should be taken in appropriate quantities and properly prepared. A larger quantity than necessary may overtax the diges- tive organs and thus yield less than the required amount of nutritive material to the body. Physical exertion increases the consumption of fatty principles. Hence, as in the case of the athlete or prize-fighter in training, larger quantities of these principles are required to keep the nutrition of the body at the standard of health. During mental work, however, less carbohydrate material is consumed than during physical labor. The greater consumption of carbohydrates during muscular exer- cise is shown by the following table, which gives the amounts of carbon dioxide and nitrogen excreted by a man at rest and during labor : — Table XVIII. COj Excreted. Nitrogen Excreted. At rest At work 912 grammes 1284 36.3 grammes. 36.8 " In youth the processes of combustion (production of carbon dioxide) go on with greater rapidity than after adult life is reached. For this reason young persons rarely get fat, the fat-producing food being burnt up in the body by the greater metabolic activity of the young cell. Hence, fats and carbohydrates should form a larger relative proportion in the diet of the young than in that of grown persons. FOODS OF ANIMAL ORIGIN. 119 Low external temperature causes a greater and more rapid con- sumption of fat than high external temperature. During febrile conditions, however, the destruction of stored-up fat in the body — the wasting away — is one of the most notable phenomena; hence the importance of supplying fat and fat-producing food in chronic febrile diseases. "Der Mensch ist was er isst/' said Ludwig Feuerbach." The pun- gency of the epigram is somewhat lost in the translation, which is, literally, "Man is what he eats.'' The intimate relations of mental, moral, and physical conditions of health to the quality and quantity of food deserve the earnest attention of the educated physician and sanitarian. CLASSIFICATION OF FOODS. Foods and victuals are generally divided into foods proper and so-called accessory aliment. The classification is not exact, however, as the latter, which are commonly regarded as articles of luxury, may under certain circumstances become necessities, and hence should not be considered as forming a separate class. Foods are either of animal or vegetable origin. Those derived from animal sources are milk, the flesh of animals, birds, reptiles, and fish, and the eggs from the three last named. The foods derived from the vegetable kingdom comprise the seeds of various plants (cereals, legumes), roots, herbs, ripe fruits,- the fleshy envelopes of various seeds (which may properly be classed with the fruits), and various fungi. There are also in common use a number of beverages, e.g., water, alcoholic liquors, alkaloid infusions (tea, coffee, cocoa), etc. In addition, a number of substances or compounds are in common use as condiments. Their function is either to render victuals more palatable, or to promote digestion and assimilation. Vinegar, must- ard, and common salt are familiar examples. FOODS OF ANIMAL ORIGIN. Milk. — Human milk is, so far as known, the one perfect food for man found in nature. It contains, in proper proportion, representa- tives of all the different classes of proximate principles necessary to nutrition. One hundred parts contain about 2.5 parts of proteids " Gottheit, Freiheit und Unsterblichkeit von Standpunkt der Anthropolo- gie, p. .5. 120 TEXT-BOOK OF HYGIENE. (casein and albumin) ; 3.9 parts of fat (butter) ; 6.0 parts of sugar, and .5 of salts. The reaction of human milk is slightly alkaline; that of fresh cow's milk is neutral. In human milk there are 13.9 parts of solid matter to 87.1 of water, while in cow's milk the proportions are : Proteids, 4.0 per cent.; fats, 3.4 per cent.; sugar, 3.8 per cent.; salts, 0.6 per cent., or 11.8 total solids and 88.2 water.'^ Of the solids in milk, cow's milk contains more proteids, while human milk is richer in fats and sugar. Hence, in using cow's milk as a substitute for human milk the proteids are diluted by the addition of water, and the non-nitrogenous components increased by adding sugar, and, under some circumstances, fat (cream). Goats' and asses' milk are sometimes used as substitutes for human milk, but they do not approach much nearer in composition to the latter than does cows' milk. On standing, the fatty constituent of milk, the cream, separates, and on account of its less specific gravity rises to the surface, where it forms a layer of varying thickness. After standing a longer interval the milk undergoes certain physical and chemical changes. Lactic acid is formed at the expense of part of the sugar of milk (a sort of fermentation taking place), and, acting upon the casein, produces coagulation. This is the so- called "bonny-clabl3er." AYhen the fermentation continues, especially under a slightly elevated temperature, the solid portion becomes con- densed (curd), and a sweetish-acid, amber-colored liquid, the whey, separates. The curd, after further fermentation, under appropriate treatment, becomes converted into cheese. Whey is sometimes used alone or mixed with wine as an article of diet for the sick. Butter is made from the cream by prolonged agitation in a churn. The fat-globules adhere to each other and form a soft, unctuous mass, of a yellowish color, solid at ordinary temperatures. After the butter is all removed in this way the balance of the cream remains in the churn as buttermilk. This is an article of considerable nutritive value, although its excess of acid renders it unsuitable as an article of diet in many cases. The specific gravity of fresh milk should not be below 1030. It should, however, be borne in mind that the richest milk is not always that which has the highest specific gravity. In fact, a sample of rich milk, containing a large proportion of cream, may show, when ' Average of a number of analyses. FOODS OF ANIMAL ORIGIN. 121 tested with the lactometer, a lower specific gravity than a specimen of much poorer milk. Hence, the lactometer, although a useful instru- ment in guarding against excessive dilution of milk with water, is not a very trustworthy guide in determining the quality of the milk. Objections are often urged against the use of so-called "skim- milk," i.e., milk from which the cream has been removed. In some cities in this country the police, or representatives of the sanitary au- thorities, seize and confiscate all skim-milk found in possession of dealers. There appears to be no rational l)asis for the opinion held by many that skim-milk is not a proper and useful article of food. Before the lactic-acid fermentation has taken place it differs from fresh milk merely in the fatty and other matters removed in the cream. It con- tains nearly all of the proteids, sugar, and salts of whole milk, and may be used as an article of food with great advantage and entire safety. In certain disordered states it is of exceptional value as an article of diet. The sole objection of any weight to skim-milk is that it may be at times sold fraudulently as fresh milk. This is, how- ever, a question of little sanitary interest, but one principally of com- mercial ethics. Milk is frequently adulterated by the addition of water. More deleterious substances are rarely found. An excess of water gives the milk a bluish tinge and reduces its specific gravity. The addition of water may become especially dangerous by introducing the virus of some of the acute infectious diseases. Thus, the localized epidemics of typhoid fever have, in quite a number of instances, been traced to mixing the milk with water containing the germ of this disease. It should, however, be stated that milk which contains the germ of ty- phoid fever has not necessarily been adulterated by the addition of water. The typhoid bacillus may have been introduced with the water used in washing the can, and adhered to the sides of the latter. In filling the can with milk a good culture medium is supplied in which the typhoid bacillus flourishes. Diphtheria may also be communicated through the milk, by the latter becoming directly contaminated by the specific germs of this disease. It has long been a mooted question whether acute or chronic infectious diseases of the milk-giving animal may be communicated to persons using the milk of such animals. While there is little posi- tive knowledge upon the subject, it would seem prudent to avoid the use of milk from diseased animals, if possible, or to destroy any or- ganic virus the milk may contain by previously boiling the milk. After thorough boiling little fear need be entertained of communi- 122 TEXT-BOOK OF HYGIENE. eating either acute or chronic infectious diseases through this medium. Demme and UfEehnann have reported cases which seem to demon- strate the possibility of tuberculous infection through the medium of the milk. Professor Bang, of Copenhagen, made a series of ex- periments and observations which led him to the conclusion that the milk of tuberculous cows and tuberculous women, in which there are no lesions in the mammary gland, only exceptionally contains the contagion. Professor Bang, at the same time, points out that the milk from tuberculous udders is extremely dangerous, and that the tubercle bacilli are to be found not only in the milk itself, but in the cream, buttermilk, and butter made from it; and that such milk is some- times infective by ingestion, even after exposure of 65° C. of heat, and by injection into the peritoneal cavity after exposure of 80° C. The infectiousness of the milk of cows suffering from splenic fever (milzbrand, anthrax) has been proven by Bollinger and Feser. Anthrax bacilli have been found in such milk by Chambrelent and Moussons. The agency of milk in the spread of scarlet fever is well recog- nized, but the manner in which the contagion gains access to the milk is not well understood. Several years ago an incident happened in England which seems to prove a close connection between this widespread and fatal disease and a disorder in the milk cattle. The evidence in support of this view is as follows: Mr. W. H. Power, of the English Local Government Board, was detailed to investigate cer- tain outbreaks of scarlet fever which seemed to have especial relation to the milk-supply from a particular dairy-farm. Upon inspection this dairy was found to be in excellent sanitary condition as regards cleanliness, water-supply, sewerage, etc., and for a time considerable difficulty was experienced in locating the cause of the outbreaks. Improbable as it may at first sight appear, it seems to have been in- contestably established that the epidemics of scarlatina were due to the use of milk obtained from cows attacked by a peculiar disease manifested by a vesicular eruption followed by ulceration of the udder. The chain of circumstances connecting the disease in the cows with the outbreak of scarlet fever in certain districts in London, supplied with milk from the diseased cows, was so strongly forged by the able investigator into whose hands the work had been committed by the authorities, that hardly a doubt can exist that the one disease owed its origin to the other. The pathological evidence furnished by Dr. Klein lends strong support to the view that the Hendon cow disease and scarlet fever are FOODS OF ANIMAL ORIGIN. 123 intimately related to each other. A bacterial organism was found in the material from the ulcerated udders of the sick cows, which pre- sents similar characteristics to a micro-coccus found by the same ob- server in the blood of scarlet-fever patients. These results, however, require more extended investigations before they can be unreservedly accepted. The milk of cows fed upon the refuse of breweries and distilleries — "swill-milk" — is believed by many physicians to be unwholesome. If so, it is, probably, only by reason of the unfavorable hygienic con- ditions under which the animals are kept. If the stables are clean, dry, well- ventilated, and the animals receive plenty of fresh air and exercise, swill-fed cows should produce as nutritious milk as when they are fed upon different food. Much of the agitation against "swill- milk" is more prompted by political demagogism than by scientific knowledge. The milk of animals suffering from certain diseases is often dan- gerous to health. In some of the Western and Southern United States, cows are not infrequently attacked by an acute febrile disease called "the trembles," from one of the prominent symptoms. The milk of cows suffering from this disease produces severe gastro-intes- tinal disorder, collapse, fever, etc., in the consumer. This disease, called "milk-sickness," is fatal in a pretty large proportion of cases. It is said that the flesh of animals with "the trembles" will, if eaten, produce similar dangerous effects. A late writer (Dr. Beach, of Ohio) estimates that 25 per cent, of the Western pioneers and their families died of this disease. For the ready determination of the quality of milk, instru- ments known as lactoscopes, lactometers, and creamometers are used. The lactoscope indicates the opacity of the milk, upon which the pro- portion of cream depends. One convenient modification of the lacto- scope is the little instrument termed the pioscope. This consists of a disk about 6^/0 centimeters in diameter, with a slight depression in the centre. A little milk is placed in the depression and covered with a glass disk, clear in the centre and opaque around the border, which is divided into six divisions of different shades, varying from white to dark gray. The quality of the milk is marked upon the division whose color corresponds with that of the milk in the centre. A better, but still not very accurate indicator of the quality of the milk, is the creamometer. This consists of a cylindrical glass vessel with the upper half divided up into hundredths. The glass is filled up to the zero mark with milk, and allowed to stand until all the 124 TEXT-BOOK OF HYGIENE. cream has separated. The thickness of this layer is then read off on the scale. In Chevallier's instrument, 10 per cent, of cream is the minimum proportion that should be furnished by the milk. The specific gravity, which is a fair guide to the quality of the milk, with the reservations above mentioned, is measured by means of the lactometer or lactodensimeter. The specific gravity of good cows' milk should not be less than 1029. Fig. 10. — Chevallier's Creamometer. In order to prevent the rapid fermentation of milk various methods of preservation have been adopted. The addition of alkalies, or antiseptics, retards the lactic-acid fermentation, while the abstrac- tion of a portion of the water and addition of sugar (condensed milk) preserves it for an indefinite time. The mere addition of water re- stores it to nearly its original condition. Tyrotoxicon in Mill'. — This substance, first found in poisonous cheese, and later in milk, ice-cream, custards, etc., is believed by Pro- fessor Vaughan to be the cause of true cholera infantum, and many of the clinical phenomena of this disease lend strong support to such a view,. The conditions under which the poison is developed have not yet been sufficiently studied to enable correct conclusions to be drawn. Recent studies, however, indicate that the summer diarrhea of infants FOODS OP ANIMAL ORIGIN. 125 is caused by putrefactive bacteria in milk. The intimate relation be- tween milk containing large numbers of bacteria and diarrheal dis- eases in infants and children is becoming more and more apparent. Butter. — Butter is of especial value as food on account of the large amount of easily digestible fat which it contains. It is almost always used as accessory to other articles of food, to render them more palatable. When pure and fresh, it is one of the most delicious of foods. It soon undergoes the butyric-acid fermentation, however, becoming "rancid," as it is termed, when it is unfit for food. The great demand for butter and its consequent high price have led to its extensive sophistication. Butter is now very largely sub- stituted by an artificial substitute termed oleo-margarine, or butterine. This artificial butter is made from beef -suet by the following process : Fresh beef-fat is melted at as low a temperature as possible, never higher than 52° or 53° C. [136° to 128° F.]. All membrane and tissue are then removed, and the resulting clear fat is put into presses, where the stearine is extracted. The liquid fat, free from tissue, and with nearly all its stearine removed, is known as "oleo-margarine oil." The next step in the process is the "churning." The oil is al- lowed to run into churns containing milk and a small quan- tity of coloring-material (annatto), where, by means of rapidly- revolving paddles, it is churned for about an hour. When this part of the process is complete, the substance is drawn off from the bottom of the churn into cracked ice. When cool it is taken from the ice, mixed with a proper quantity of salt, and is then worked like butter and put into firkins for the market. It is also moulded into attrac- tive prints in imitation of dairy-butter.^ When the materials from which oleo-margarine is made are sweet and clean, and when the pro- cess of manufacture is properly conducted, the resulting product is an entirely harmless article, and probably differs very little in nu- tritive value from butter itself. The only objection to oleo-margarine is a commercial one. It is so much like butter that dishonest dealers find it possible to substitute this product for the higher-priced natural product. Cheese. — The value of cheese as a food depends upon the large amount of proteids and fat which it contains. The rich varieties of cheese, such as From age de Brie and Eoquefort, contain on an average 35 per cent, of fat and 27 per cent, of proteid compounds. Parmesan contains only about 18 per cent, of fat and nearly 40 per cent, of *Dr. W. K. Newton, Fifth Annual Report of the State Board of Health of New Jersey, 1881, p. 107. 126 TEXT-BOOK OF HYGIENE. proteidSj while Edam and Cheshire cheese, which may be considered as standing about midway between the above, contain 30 per cent, of fat and nearly 28 per cent, of proteids. From these figures it ap- pears that cheese is one of the most nutritious aliments obtainable, but it cannot be eaten in large quantities at a time, as it is exceedingly liable to cause disturbances of the digestive organs. The constipating property of cheese is well Icaown to the public. The relative value of different kinds of cheese in alimentary principles is given in the following table: — Table XIX. Kind of Cheese. Proteids (percent.). Fats (per cent.). Sugar (percent.). Salts (percent.). Cheshire 27.68 27.46 5.89 5.01 Edam 24.07 30.26 4.48 4.91 Holland 29.48 26.71 2.27 4.62 Roquefort Neufchatel 27.69 17.44 33.44 40.80 3.15 5.21 5.35 2.05 Parmesan 41.19 19.52 1.18 6.31 Cheese is not often adulterated. The only articles used with success in its sophistication are lard and oleo-margarine, which are incorporated with the casein during the process of manufacture. It sometimes undergoes chemical changes which render it intensely poisonous Avhen eaten. Professor V. C. Vaughan, of the University of Michigan, has ascertained that the substance causing the poisonous symptoms is a chemical compound termed by him tyrotoxicon. This same poison has also been found by Professor Vaughan and other chemists in ice-cream and fresh milk, which produced poisonous symptoms when consumed. The poison is supposed to be a ptomaine produced by the agency of a micro-organism, which has, however, not yet been isolated. Meat. — The flesh of mammals, reptiles, birds, fish, and inver- tebrate animals is used as food by man. Falck^ has classified the varieties of animals which furnish food to the inhabitants of Europe. There are 47 varieties of the mammalian class, 105 of birds, 7 of amphibia, 110 of fish, and 58 of invertebrates. ® Das Fleiseh, Gemeinverstaendliches Handbuch der Wissenschaftliclieii imd Praktisclien Fleischkunde. FOODS OF ANIMAL ORIGIN. 127 Meat is the most important source of proteids in the food. In the more commonly used varieties of meat the proteids and fats consti- tute from 25 to 50 per cent, of the entire bulk, the proportion depend- ing largely upon the age of the animal and its bodily condition. The following table shows the influence of these two factors upon the rela- tive proportions of the fats and proteids in the meat : — Table XX. ^^ Proteids (jDcr cent.) Fats (per cent.). Moderately fat beef Lean beef . . . . Yeal Very fat mutton Fat pork . . . . Lean pork . . . . Hare Lean chicken . . . 21.39 20.54 10.88 14.80 14.54 19.91 23.34 19.72 5.19 l.tS 1A1 36.39 3t.34 6.81 1.13 1.42 The flesh of animals, which is neutral in reaction immediately after death, soon becomes acid in consequence of the formation of lactic acid. The acid, acting upon the sarcolemma and the muscular fibre, renders it softer and more easily permeable by fluids when cook- ing, and more susceptible to the action of the gastric juice when the meat is taken into the stomach. Certain kinds of meat — mutton and venison, for example — are often kept so long before being eaten that a considerable degree of putrefaction has taken place when they are brought upon the table. The wisdom of this practice is questionable from a hygienic point of view. Meat is sometimes eaten raw, but it is usually first cooked. The methods of cooking in general use are boiling, frying, roasting, broil- ing, and baking. By either of these methods of cooking, when prop- erly carried out, the nutritious properties of the meat are preserved, and it is rendered digestible. The culinary art deserves the closest attention of students of hygiene. A number of soluble preparations of meat (beef -extract, beef- essence, beef-juice) are found in the market, and highly recommended as containing all the nutritious qualities of the meat from which they '"Abridged from Loebisch; article "Flcisch" in Realencyclopaedie d. ges. Heilkunde, vol. v, p. 340. 128 TEXT-BOOK OF HYGIENE. are prepared. These, and similar products of domestic preparation (broths and teas), contain in reality very little nutritive material, but are of use almost solely as stimulants to the appetite and digestion. They have a place in the dietary of the sick but their nutritive value is small. On the other hand, a number of partly or wholly predigested (peptonized or pancreatized) preparations of meat are offered for sale, many of which have a high nutritive value. They cannot, however, be used as articles of diet except for a short time, or as a temporary succedaneum for meat in diseases attended with weakness or derange- ment of the digestive organs. Most of the predigested beef-prepara- tions on the market owe their effect to the large amounts of alcohol which they contain. Meat may be unfit for food from various causes. Thus the flesh of animals djing from certain diseases — splenic fever, pleuro-pneu- monia, tuberculosis in its advanced stages, cow- or sheep- pox — should not be used as food when it can be avoided. Cases are on record proving the poisonous character of meat from animals which suffered, at the time of death, from some of the above-mentioned diseases. The most important condition to be borne in mind is that certain parasites (trichina spiralis, echinococcus, cysticercus), which fre- quently infest the flesh of animals, especially hogs, not infre- quently give rise to serious or even fatal diseases in persons consum- ing such meat. Any meat containing these parasites or suspected of containing them, should therefore not be used as food unless pre- cautions be first taken to destro}^ the life of the parasite. Of the parasites mentioned the trichina spiralis is the most im- portant in this connection, as it frequently occurs in the flesh of hogs, rats, dogs, cats, and other carnivorous animals. Eats are said to be infested with the parasite more frequently than any other animals. The trichinae are found in two forms, one, the mature form, inhabiting the intestinal canal. The immature form, or muscle trichinfe, are found in striped muscle, coiled into spirals and encysted in a fibrous capsule. They gain access to their host in the following manner: Flesh containing living trichinae is taken into the stomach, where the muscular tissue and the fibrous envelope are dissolved, and the in- closed worms set free. These mature in the intestinal canal, where sexual reproduction takes place, and the young embryos pass through the intestinal walls and other tissues until they become imbedded in striated muscle. Localized epidemics of trichinosis have been re- ported in this country and Europe, and in nearly every instance the FOODS OF ANIMAL ORIGIN. 129 source of the disease has been traced to the ingestion of uncooked pork. Meat known to be trichinous should not be used unless in times of great scarcity. It may, however, be rendered innocuous by thorough cooking. A temperature of 60° to 70° C. (140° to 160° F.) destroys the life of the parasite and renders the meat safe. On ac- count of the frequent occurrence of trichinge in pork, this meat should never be eaten unless thoroughly cooked. It has been ascertained that salted and smoked pork is not free from danger, as the parasites are not killed in the process of curing the meat. Hence, ham and sausage should not be eaten raw, as the danger from these articles is almost equally as great as from fresh pork. Cysticercus cellulosa, the transition form of one variety of tape- worm, and which is the parasite in measly pork, may also gain en- trance to the human body, and, failing to undergo development, cause very serious lesions of various organs and tissues. The frequency of tape-worm is evidence that pork is often thus diseased. The use of partially decayed meat or fish has often been the cause of serious or fatal illness. Sometimes the illness partakes of the character of septic infection. In these cases it is probable that the morbid process is due to the action of the organisms of putrefaction. In other cases the symptoms are widely different. These cases have been the source of much perplexity to physicians and toxicologists until very recently. Selmi, Husemann, Brouardel, Casali, and others have drawn attention to certain intensely poisonous chemical com- pounds found in decomposing flesh, and which have been named by Selmi ptomaines. While there is still much uncertainty concerning the nature of these compounds, it seems pretty well established that when flesh undergoes decomposition, in the absence of oxygen, certain unstable chemical combinations are formed which act as violent poisons. Selmi, followed by most toxicologists, believes these com- pounds to be alkaloids, analogous to the vegetable alkaloids, such as morphine, atropine, etc. Casali, on the other hand, disagrees with this opinion, and believes the ptomaines to be amido compounds. Huse- m.ann regards Casali's hypothesis as plausible, inasmuch as the for- mation of amido compounds in animal and vegetable bodies during decomposition is well established. The form of poisoning due to the organisms of putrefaction is not infrequent. An extensive outbreak of this nature occurred at Andelfingen, in Switzerland, in 1839. A musical festival was held, at which there were over 700 present. Out of these 444 were suddenly attacked by violent gastro-enteric and nervous symptoms. Ten of the 9 130 TEXT-BOOK OF HYGIENE. patients died. The illness was traced to roast veal, which had been kept in a warm place for two da3'^s after roasting, and which was prob- aly in a state of partial decomposition. The class of cases which seem more probably due to the action of ptomaines or related poisons, have been frequently observed after eating sausages or canned meats. Sausage poisoning is not rarely ob- served in Germany. It has been ascertained that the internal portions of the sausage are the most poisonous. It is supposed that the ptomaines, which are formed in the absence of oxygen, are the active agents in the production of the train of symptoms. Poisoning by canned meat seems to be due to a similar poison. In July, 1885, an outbreak of disease, due to eating unwholesome beef, was caused at Momence, Illinois. Chemical examination of specimens of the meat showed the presence of an alkaloidal body which was believed to be a ptomaine, but its nature was not definitely determined. Fish, oysters, crabs, and lobsters frequently give rise to symp- toms of poisoning. In most of these cases the poisoning is probably due to partial decomposition, but it is a well-known fact that oysters and crabs are unfit for food at certain seasons. Some persons, how- ever, are subjects of a peculiar idios^Ticrasy, in consequence of which shell-fish always produce certain unpleasant symptoms, among which nettle-rash and a choleraic attack are most prominent. That form of fish-poisoning known among the Spaniards in the Vfest Indies as siguaiera is, however, very grave. The mortality is large, and in many cases death succeeds rapidly upon the attack. The sjTmptoms are as follow : Sometimes suddenly, sometimes preceded by dizziness and indistinct vision, great prostration and paralysis occur. Often death follows the onset of the symptoms in two and three hours. Exceptionally in less than twenty minutes. In most cases consciousness is totally lost ; in others it persists, with interrup- tions, until death. Sensation and the powers of speech and deglutition fail. The jaw muscles become paralyzed, the pulse is slowed, and the temperature diminished. There is sometimes vomiting, but no purg- ing. The secretion of the kidneys is also checked. Dr. Mc Sherry states^^ that he has seen all these symptoms produced by eating oysters, lobsters, and crabs, unseasonably. In Eussia a form of poisoning has often been observed which re- sults from eating salted sturgeon. In the fresh state these fish are perfectly wholesome, bu!t when salted and eaten raw they produce a " Health and How to Promote itj p. 143. FOODS OF ANIMAL ORIGIN. 131 very fatal illness. The mortality is said to reach 50 per cent, of those attacked. No cases traceable to this cause have been observed in this country. Kecent investigations show that many cases of meat poisoning are caused by the bacillus of Gaertner, which belongs to the colon group of intestinal bacteria, while other cases are caused by a bacillus discovered by Van Ermengem in 1896 — the bacillus botulinus. It has been shown, beyond question, that the flesh of beeves suf- fering, when killed, from splenic fever, will produce this disease in the human subject. In 1874 an extensive and violent outbreak of an acute disease, characterized by vomiting and purging, fever and dizziness, occurred at Middleburg, in Holland. Three hundred and forty-nine persons were attacked, of whom 6 died. The outbreak was traced to eating liver-sausage (Leberwurst), in which the characteristic bacillus of splenic fever was found on microscopic examination. In July, 1877, an outbreak of choleraic disease, from eating carbuncular meat, oc- curred in the town of Wurzen. In the latter epidemic the bacillus of splenic fever (Bacillus antliracis) was found in the intestinal canal and in the blood of those attacked. In Detmold, in Germany, an outbreak of violent gastro-intestinal inflammation, accompanied by a high fever, occurred. Among the 150 persons attacked 3 died. The disease was traced to eating the meat of a cow suffering, before death, from pleurisy (probably pleuro- pneumonia). In July, 1880, 72 persons who had eaten of certain beef and ham- sandwiches in Welbeck, England, were attacked by choleraic diar- rhea; 4 of the cases died. Inflammation of the lungs and small intestines was the most prominent pathological condition found post- mortem. The smaller blood-vessels of the kidneys were filled with finger-shaped bacilli, which, when cultivated and inoculated into guinea-pigs, rats, and white mice, produced similar pathological con- ditions. At Nottingham, England, in 1881, a number of persons were attacked by a similar train of symptoms after eating baked pork. One case terminated fatally out of the 15 attacked. It is uncertain whether the meat in these two instances was from diseased animals or whether it had undergone partial decomposition. The former is the more probable supposition, although the organisms found were neither those of splenic fever nor swine plague, but resembled those of symptomatic anthrax (black leg or black quarter). 'V\TnethGr the flesh of tuberculous animals can communicate tuber- culosis to the consumer is still an unsettled question. Foreign veterin- 132 TEXT-BOOK OF HYGIENE. arians and hygienists who have studied the question incline to the view that there is danger of such transmission. At the International Sani- tary Congress of 1883, at Brussels, the subject was discussed, and M. Lydtin, the chief veterinary surgeon of the Grand Duchy of Baden, submitted the following propositions, which were adopted by the Con- gress — 1. That the flesh and viscera of tuberculous animals may be used as food, provided the disease is only commencing, the lesions extend- ing to but a small part of the body, the lymphatic glands being still healthy; provided the tubercle centers have not undergone softening, and provided the carcass is well nourished and the flesh presents the characters of meat of the first quality. 2. That the flesh of animals showing very pronounced tuberculous infection should be saturated with petroleum, and afterward burned under the direction of the police. 3. That the milk from cows affected with pulmonary phthisis, or suspected of having it, should not be consumed by man or other animals, and the sale of it should be strictly prohibited. The congress for the study of tuberculosis, which met in Paris in 1888, adopted resolutions of a more decided character against the use of meat and milk from tuberculous animals. Eecent investiga- tions fully substantiate the opinions expressed at these congresses. Certain animals can devour with impunity substances which are intensely poisonous to human beings. The flesh of the animals may be impregnated with these poisons, and cause serious and fatal illness in persons partaking of it. In this way may, perhaps, be explained the cases of poisoning sometimes following the eating of partridges and other birds. The prevention of disease from tainted meat is one of the most important problems of public hygiene. Food animals should be in- spected by qualified inspectors before slaughtering, to exclude animals suffering from diseases that would vitiate the meat. When the meat is exposed for sale upon the dealer's stall it should be again inspected, and all found unfit for use as food confiscated and destroyed. Meat, in which the presence of trichinge or other parasites is suspected, should be examined microscopically.^^ The recent disclosures in con- nection with the scandalous neglect of sanitary precautions in the "The prevention of the diseases of animals by National and State au- thorities is one of the most logical and thorough-going means of preventing disease from unAvholesome meat. The American Public Health Association has for some years devoted considerable attention to the investigation of the dis- eases of animals and means for their prevention. The Department of the In- terior of the National Government has likewise made the diseases of cattle and hogs a subject of study and published some valuable reports thereon. FOODS OF VEGETABLE ORIGIN. 133 packing-houses in Chicago emphasize the necessity of great vigilance in the inspection of meats at these establishments. However, these disclosures, unpleasant as they were at the time, led to prompt eradi- cation of the existing evils. Eg-gs. — Although eggs contain a large amount of the proteid and fatty alimentary principles, their value as food has probably been greatly overrated. The savory taste and ready digestibility of eggs have, however, rendered them a popular article of food. For obvious reasons, the eggs of the common barnyard fowl are most frequently used, those of ducks and geese being far inferior in flavor to the first named, and being likewise less easily obtained. The method of cooking eggs is generally supposed to have con- siderable influence upon their digestibility. According to Dr. Beau- mont's experiments made on Alexis St. ]\Iartin, raw eggs are digested in one and a half to two hours, fresh-roasted in two hours and fifteen minutes, soft-boiled or poached in three hours, and hard-boiled or fried in three and a half hours. These experiments are, however, of very little value as a basis for general conclusions. It is probable that a hard-boiled egg is quite as easily digested in the healthy stom- ach as a raw one, if care be taken to masticate it well and eit bread with it, so that it is introduced into the stomach in a finely-divided state. Eggs readily undergo putrefaction, when sulphuretted hydrogen is formed in them in large quantities. When this has taken place they are manifestly unfit to be used as food. FOODS OF VEGETABLE ORIGIN. Bread. — The various cereal grains, when ground into flour, are used in making bread. The flours of wheat, rye, barley, buckwheat, and Indian corn are almost exclusively used in bread-making. The bran or cortical portion of grain contains a larger percentage of pro- teid principles than the white internal portion; hence, flours made from the whole grain (bran flour, Graham flour) if finely ground are more nutritious than the white flours. The latter are, however, more digestible, and hence furnish a larger proportion of nutriment, be- cause the principles contained in white flours are absorbed and as- similated to a greater degree. Good bread should be light, porous, and well leaked. The light- ness anrl porosity are due to carbon-dioxide gas imprisoned in cavities of the dough during the process of bread-making. By adding yeast 134 TEXT-BOOK OF HYGIENE. to the dough a fermentation is caused in the latter, in consequence of which a portion of the starch is converted into sugar, and then into alcohol and carbon dioxide. During the process of mixing the dough the entire mass becomes permeated by the gas, which, on heating, ex- pands and leaves the numerous large and small cavities throughout the loaf which indicate properly made bread. Instead of yeast some persons use leaven, which is simply a por- tion of fermenting dough saved from a previous baking. A small quantity of this added to a mass of dough starts up the fermentation in a similar manner to that of yeast. The production of carbon dioxide by fermentation in the dough goes on at the expense of part of the starch. It has been proposed, therefore, to supply the carbon dioxide from without, thus saving the entire amount of the carbohydrates present in the flour. This is accomplished in two ways — first, by the use of some alkaline car- bonate or bicarbonate (bicarbonate of sodium, carbonate of ammo- nium), the carbon dioxide being set free on the application of heat; or, secondly, by forcing gas, previously prepared, into the dough by means of machinery. Flour is not infrequently adulterated with chalk, gypsum, pipe- clay, and similar articles. These are easily detected by adding a min- eral acid, which produces effervescence when it comes in contact with the alkaline carbonate used as an adulterant. Potato- and Ijean- meals are also used as adulterants of the higher grades of flour. Bakers often mix alum with inferior grades of flour. This imparts a greater degree of whiteness to the bread, and, in addition, enables it to retain a large proportion of water, thereby increasing the weight of the loaf. Formerly diseased grain (ergotized rye) often caused outbreaks of disease when the flour made from the diseased grain was used in bread-making. At present time such accidents rarely occur. In some parts of Italy it is said that an endemic disease — pellagra — is caused by the consumption of diseased Indian corn. The evidence in favor of this view, is, however, not unquestioned. Potatoes and rice are often used with satisfaction as substitutes for bread. They both contain a large proportion of carbohydrates. Indian corn (hominy) and oatmeal are likewise wholesome and nutri- tious foods of this class. The leguminous seeds (beans, peas, lentils) furnish a food con- taining a large percentage of proteids. According to the analyses of FOODS OF VEGETABLE ORIGIN. 135 Koenig^^ the average composition of the most frequently used legumes in the dried condition is as follows : — Table XXI. Beans. Peas. Lentils. Ground-nuts 1* Water, per cent. . . . Solids, per cent. . . . 13.6 86.4 14.3 85.7 12.5 87.5 6.5 93.5 Proteids, per cent. . . Fats Carbohydrates, per cent. Cellulose, per cent. . . Ash 23.1 2.3 53.6 3.9 3.5 22.6 1.7 53.2 5.5 2.7 24.8 1.9 54.7] 3.6; 2.5 28.2 46.4 15.7 3.2 Beans, peas, and lentils are often added to other articles of food with advantage. An important article of food for armies has been made of various legumes ground into flour and mixed with fat, dried and powdered meat, salt, and spice. This constitutes the so-called "Erbswurst," or pea-sausage, which formed such an important part of the dietary of the German army in the Franco-German war of 1871. Bean- and pea- meals are also used sometimes as additions to other flours in bread-making. The dried leguminous fruits cannot be used as regular articles of diet, however, as they soon pall upon the taste, and produce indigestion, nausea, and other intestinal derangements. Green Vegetables. — The plants usually classed together as "vegetables,^' the products of the market-garden or truck-farm, com- prise cabbages, turnips, parsnips, onions, beets, carrots, tomatoes, let- tuce, green peas and beans, and similar articles. They all contain a large proportion of water, a variable proportion of sugar, and a small percentage of proteid principles. Much of their palatability and digestibility depends upon the micthods by which they are prepared for the table. All garden vegetables should be used soon after being gathered, as they rapidly undergo decomposition, and are liable to produce derangements of the digestive organs if used under these conditions. Fruits and Nuts. — These generally contain large quantities of sugar and fats. They form agreeable additions to other articles of diet, but are insufficient to sustain life. The use of fruits usually "Die Mensehlichon Naln-ungs und Genussmittel, ii, p. 288. "The American pea-nut, the fruit or nut of Arachis hypogosa. 136 TEXT-BOOK OF HYGIENE. produces copious intestinal evacuations, and tliey are, therefore, espe- cially to be recommended to persons of sedentary occupations, in whom torpidity of the bowels is so frequently present. Condiments. — Various aromatic herbs and seeds are used as addi- tions to other articles of food, to increase their sapidity and to pro- mote a larger flow of saliva and gastric juice, and so assist digestion. Mustard, pepper, allspice, and vinegar are the principal condiments. Within certain limits they are not injurious, but the tendency in the use of all stimulants is to exceed a healthful limit. Condiments, as well as other stimulants, should be used in moderation. COOKING. Much more attention than is generally given should be paid by physicians to the culinary art. The manner in which food is cooked has no little influence upon its digestibility. There can be no question that the extreme prevalence of functional indigestion in this country is almost exclusively dependent upon bad cooking. The various methods of cooking are boiling, frying, roasting, broiling, and baking. By either of these methods food can be cooked so as to be palatable as well as digestible; on the other hand, the choicest article can be utterly spoiled and rendered unfit to be taken into the human stomach. It depends, therefore, not so much upon the method of cooking, as upon the knowledge and art of the cook. Boiling. — ]\Ieats of all kinds are rendered tender and digestible by boiling. In order to retain the flavor of meat, the water should be boiling when the meat is put into it. By the heat of the boiling water the albumin on the outside of the meat is coagulated and the juices and flavor are retained within. After a few minutes the temperature of the water should be reduced to 71° to 77° C. (160° to 170° F.), and maintained at that height until the meat is tender. By this process a much more savory piece of beef, mutton, or fowl can be obtained than where the meat is put into cold water and thus gradually heated. The latter m.ethod is, however, the proper one to be followed when good soup or broth is desired. In boiling vegetables, as much care is necessary as in boiling meat or fish. Potatoes and rice should be steamed, rather than boiled. The difiiculty of obtaining a good cup of coffee, especially in the northern part of the United States, illustrates the prevailing ignor- ance upon one of the simplest points in the art of cooking. Coffee COOKING. 137 should never be served in the form of a decoction ; that is to say, it should never be boiled. Properly made it is an infusion, like tea, which no one ever thinks of boiling. The difference between an in- fusion (especially if made by percolation) and a decoction of coffee can only be appreciated by those who have enjoyed the one and en- dured the other. Frying. — Frying, if properly done, is really nothing less nor more than boiling in oil or fluid fat of some kind. Olive-oil is pre- ferable, but is not essential; butter, beef-drippings, lard, or probably cotton-seed oil may be substituted for it without disadvantage. The principle of frying depends upon the fact that the temperature of oil can be raised to such a height as to produce instant coagulation on the surface of meat, fish, or other objects immersed in it while hot; this film of coagulated albumin imprisons the juices and flavors of the meat or fish, and prevents the fat entering and soaking the fibers with grease. Small fish or birds, properly fried, are justly regarded as delicacies by connoisseurs, but the process of saturating these ob- jects with fat while gradually heating them produces a dish that is anything rather than grateful to the palate, or conducive to good digestion. Roasting. — The fame of the "roast beef of Old England" has passed into song, but, at the present day, beef and other meats are rarely roasted, either in this country or abroad. As Sir Henry Thompson well expresses it,^^ '^the joint, which formerly turned in a current of fresh air before a well-made fire, is now half stifled in a close atmosphere of its own vapors, very much to the destruction of the characteristic flavor of a roast." It is probable that the old method of roasting before an open fire produced not only the most savory, but likewise the most nutritious and digestible, meat. It is to be much regretted that the process has fallen so greatly into disuse. Broiling and Baking. — These methods of cooking are modifica- tions of the process of roasting. Meats or fish, carefully broiled or baked, preserve their natural juices and flavors to a great extent, and retain their digestibility and nutritions properties. Of all methods of cooking these are probably the best known and most satisfactorily applied in this country.^*' "Food and Fepding, p. 45. London, 1880. "Every one intcrostfd in the proper anplieation of the principles of cook- ery should study the Lomb prize essay of the American Public Health Asso- ciation, by Mary Hinman Abel, upon "Practical, Sanitary, and Economic Cook- in<^." This little book can be ol)tained of Dr. T. A. Watson. Secretary, Concord, N. H. ; price, 2.5 cents. See, also, an essay on "The Art of Cooking," by Edward Atkinson, LL.I)., in Popular Science Monthly, November, 1889. 138 TEXT-BOOK OF HYGIENE. ALIMENTARY BEVERAGES. The alimentary beverages may be c'ivided into two classes, — those depending for their effect npon the alcohol they contain, and those whose active principles reside in certain alkaloids. They are used chiefly as digestive and nervous stimulants. BEVERAGES CONTAINING ALCOHOL. The physiological action of alcohol has been pretty fully worked out by Binz and his pupils, and by other experimenters. From these researches, it appears that the first effect of taking alcohol, sufficiently diluted, into the stomach is to increase the flow of the saliva and gas- tric juice. This effect is probably reflex, and results from a stimulation of nerve terminations in the stomach. The alcohol is rapidly absorbed, and is carried in the blood, without undergoing chemical change, to the nervous centres, lungs, and tissues generally. In the brain the alcohol probably enters into combination with the nervous tissue, modifying the normal activity of the various centres, either increasing the activity, if the alcohol is in small quantity (stimulating effect), or diminishing it if in larger quantity (depressing effect), or entirely suspending the activity of the centres, if in sufficiently large quantity (paralyzing effect). Alcohol stimulates the vasodilator nerves, causing dilatation of the smaller vessels ; in consequence of this the blood is largely sent to the periphery of the body; the blood-pressure diminishes, and heat- radiation is increased. At the same time a portion of the alcohol is used up in the lungs in the production of animal heat, thus econom- izing the expenditure of fats and proteid, and acting as a true re- spiratory food. Alcohol does not contribute nutritive material to the body; it only permits that which is stored up to be saved for other uses, by furnishing easily-oxidizable (combustible) material for carrying on the respiratory process, and supplying animal heat. During the use of alcohol the excretion of urea is diminished. This shows that waste of tissue is retarded in the body. Eegarding the statement of some authorities that alcohol does not undergo any change in the body, but is excreted unchanged, Binz asserts^'' that alcohol appears in the urine only when exceptionally large quantities have been taken, and then in very small proportion. It is not excreted by the lungs, the peculiar odor of the breath being " Realencyclopsedie d. ges. Heilk., Bd. I, p. 183. BEVERAGES CONTAINING ALCOHOL. 139 due not to the alcohol, but to the volatile aromatic ether, which is oxidized with greater difficulty, and so escajoes unchanged. While alcohol produces subjectively an agreeable sensation of warmth in the stomach and on the surface of the body, the bodily temperature is not raised. The subjective sensation is due to the dilatation of the blood-vessels and the sudden hyperaBmia of those parts. During fevers and other exhausting diseases, alcohol is invaluable to prevent waste of tissue and sustain the strength. It does not act merely as a stimulant to the circulation and nervous system, but, as above pointed out, saves the more stable compounds by furnishing a readily oxidizable respiratory food. When taken in small doses by healthy persons, alcohol dimin- ishes the temperature by increasing heat-radiation. When large quan- tities are taken, the bodily temperature is reduced by diminishing heat production, as well as by increased radiation. This is shown in the condition known as dead-drunkenness, in which the tempera- ture is sometimes depressed as much as 20° F. below the normal. Cases in which the temperature sank to 75°, 78.8°, and 83° F. have been reported, with recovery in all cases. In discussing the physiologic effect of alcohol Dr. HalP^ makes use of what he regards as the "deadly parallel" between food and alcohol : — Food. Alcohol. 1. A certain quantity will produce L A certain quantity will produce a certain effect at first, and the same a certain effect at first, but it requires quantity will always produce the more and more to produce the same same effect in the healthy body. eft'ect when the drug is used habit- ually. 2. The habitual use of food never 2. When used habitually it is likely induces an uncontrollable desire for to induce an uncontrollable desire for it, in ever increasing amounts. more, in ever increasing amounts. 3. After its habitual use a sudden 3. After its habitual use a sudden total abstinence never causes any de- total abstinence is likely to cause a rangement of the central nervous sys- serious derangement of the central tern. nervous system. 4. Foods are oxidized slowly in the 4. Alcohol is oxidized rapidly in the body. body. 5. Foods, being useful, are stored 5. Alcohol, not being useful, is not in the body. stored in the body. 6. Foods are the products of con- 6. Alcohol is a product of decom- structive activity of protoplasm in position of food in the presence of a the presence of abundant oxygen. scarcity of oxygen. " The .Journnl of the American Medical Association, vol. xlviii, No. 5, 1907. 140 TEXT-BOOK OF HYGIENE. Food. Alcohol. 7. Foods (except meats) are formed 7. Alcohol is formed in^nature only in nature for nourishment of living as an eiicretion. It is, therefore, in organisms and are, therefore, inlier- common with all excretions, inher- ently wholesome. ently poisonous, 8. The regular ingestion of food is 8. The regular ingestion of alcohol beneficial to the healthy body, but is deleterious to the healthy body, may be deleterious to the sick. but may be beneficial to the sick (through its drug action). 9. The use of food is followed by 9. The use of alcohol, in common no reaction. with narcotics in general, is followed by a reaction. 10. The use of food is followed by 10. The use of alcohol is followed an increased activity of the muscle by a decrease in the activity of the cells and brain cells. muscle cells and brain cells. 11. The use of food is followed by 11. The use of alcohol is followed an increase in the excretion of CO2. by a decrease in the excretion of CO2. 12. The use of food may be followed 12. The use of alcohol is usually by accumulation of fat, notwithstand- followed by an accumulation of fat ing increased activity. through decreased activity. 13. The use of food is followed by 13. The use of alcohol may be fol- a rise in body temperature. lowed by a fall in body temperature. 14. The use of food strengthens 14. The use of alcohol weakens and and steadies the muscles. unsteadies the muscles. 15. The use of food makes the 15. The use of alcohol makes the brain more active and accurate. brain less active and accurate. The constant use of alcohol produces in all the organs an excess of connective tissue, followed by fatty degeneration and the condition known as cirrhosis. The organs most frequently affected are the stomach, liver, and kidneys. Serious pathological alterations also occur in the circulatory, respiratory, and nervous systems. Alcohol is not necessary to persons in good health. Probably most persons, regardless of their state of health, do better without it. Its habitual use in the form of strong liquors is to be unreservedly condemned. The lighter wines and malt liquors, if obtained pure, may be consumed in moderate quantities without ill effects. Even in these forms, however, the use of alcohol should be discouraged or, perhaps, prohibited in the young. Neither in hot nor in cold climates is alcohol necessary to the preservation of health, and its moderate use even produces more in- jury than benefit. The Polar voyager and the East Indian mer- chant are alike better off without alcohol than with it. , It has long been a prevalent belief that the use of alcohol enables persons to withstand fatigue better than where no alcohol is used. BEVERAGES CONTAINING ALCOHOL. 141 A large amount of concurrent testimony absolutely negatives this belief.^'' The predisposition to many diseases is greatly increased by the habitual use of alcohol. Sun-stroke, the acute infectious diseases, and many local organic affections attack, by preference, the intemperate. A recent collective investigation by the British Medical Association brought out the fact that croupous pneumonia is vastly more fatal among the intemperate than among those who abstain from the use of alcoholic liquors. A further investigation by Baer has shown that the average ex- pectation of life among users and dealers in alcoholic liquors is very much shortened. The following table gives a comparative view of the expectation of life in those who abstained from and those who used alcohol : — Table XXII. EXPECTATION OF LIFE. Age. Abstainers. Alcohol Users. At 25 32.08 years. 25.92 " 19.92 " 14.45 " 9.62 " 26.23 years 20.01 " "35 "45 15.19 " "55 "65 11.16 " 8.04 " Table XXIII shows the influence of alcohol upon the mortality from various diseases : — Table XXIII. General Male Popu- lation (per cent.). Alcohol Venders (per cent.). Brain disease Tuberculosis Pneumonia and pleuritis .... Heart disease Kidney disease Suicide Cancer 11.77 30.36 9.63 1.46 1.40 2.99 2.49 22.49 14.43 36.57 11.44 3.29 2.11 4.02 3.70 Old age . 7.05 "See Parkes' Hygiene, 6th ed., vol. i, pp. .315-327. 142 TEXT-BOOK OF HYGIEKE. Alcohol as a beverage is consumed in the various forms of spirits, wines, and fermented liquors. The varieties of spirits most frequently used are brandy, whisky, rum, and gin. They are all procured by distillation. Brandy is distilled from fermented grape-juice, and has a char- acteristic aromatic flavor. When pure and m.ellowed with age it is the most grateful to the palate of all distilled spirits. Whisky is distilled from barley, rye, oats, corn, or potatoes. Each of these has a peculiar flavor, depending upon the particular volatile ether formed during the distillation. Eye-, barley-, and corn- whiskies are almost exclusively used in this country. Eum is distilled from molasses, and is a favorite ingredient in hot punches. It is often used with milk, eggs, and sugar, in the prepa- ration of eggnog, a highly nutritious, stimulating drink, which is often prescribed with great benefit in acute and chronic wasting dis- eases. Grin is an ardent distilled spirit, flavored with oil of juniper. It has a widely-spread popular reputation as a cure for kidney dis- eases, but is probably oftener responsible for the production of these diseases than for their cure. All of the above-mentioned liquors contain from 40 to 60 per cent, of alcohol, and should always be diluted before being taken into the stomach, in order to prevent the local irritant effects of tbe alco- hol upon the gastric mucous membrane. Wine is the product of the alcoholic fermentation of the sac- charine constituents of fruits. Wine is usually derived from the grape, though other fruits may also furnish it. The stronger wines (sherry, port, maderia) contain from 16 to 25 per cent, of alcohol. The lighter wines (hock, red and white Bordeaux and Burgundy wines, champagnes) contain from 6 to 15 per cent, of alcohol. Some also contain considerable free carbonic acid (sparkling wines), of which the champagnes are types. The red and white Bordeaux and Ehine wines are probably the least objectionable of these beverages for habitual use. They contain sufficient alcohol to be lightly stim- ulant, have a pleasant acid flavor, and are least likely to produce the bad effects which usually follow in the wake of the habitual use of the stronger wines or ardent spirits. Preference should be given to the wines of domestic manufacture, on account of the great probability of adulteration of the favorite brands of foreign wines. Many of the California, Virginia, New York, BEVERAGES CONTAINING ALCOHOL. 143 and Ohio wines compare very favorably in flavor with those imported from abroad. The more reasonable cost of these domestic wines is also a point in their favor. Cider is the fermented juice of apples. It frequently produces unpleasant gastric and intestinal disturbances when drunk, on ac- count of the large quantity of malic acid contained in it. Although it is usually ranked as a "temperance drink/' it is quite capable of causing intoxication when consumed in large quantities. Beer is the fermented extract of barley, mixed with a decoction of hops and boiled. It should be prepared only of malt, hops, yeast, and water, and should contain from 3 to 4 per cent, of alcohol, 5 to 6 per cent, of extract of malt and hops, 2 to 4 per cent, of lactic and acetic acids, and from ^/^ to ^/o per cent, of carbonic acid. This ideal is, however, rarely attained in the article sold by the liquor dealer. Numerous adulterations are practiced on the unsuspecting con- sumer. The hops are frequently substituted by aloes, calamus, and ginger, or by the more deleterious picric acid or picrotoxin. The rich brown color, sweetness, body, and creamy foam are produced by caramel and glycerin. The more expensive barley-malt is substituted by starch and rice, or grape-sugar and molasses. Ale, porter, and brown-stout are merely varieties of beer — some containing more sugar, others more extractive matter. Beer and its correlatives have considerable dietetic value, owing not merely to the alcohol they contain, but largely to the sugar and acids entering into their composition. When used to excess they often cause a considerable accumulation of fat. Kumys is the national beverage of the nomadic tribes of Tar- tary. It consists of the milk of mares which has undergone fermen- tation, partly lactic and partly alcoholic in character. Eecently it has been introduced into Europe and also into this country, where it is made of cows' milk. It is a palatable, nutritious stimulant, and is often very useful as a dietetic article in disease. Kumys may be prepared according to the following formula: To one pint of fresh milk add one tablespoonful of sugar and ^/g cake of compressed yeast. Put in bottle with patent stopper, place in warm room or near the stove for 6 to 12 hours, then cool on ice and serve. Kumys has proved a very valuable agent in the treatment of gastro-intestinal diseases. Kefyr is a product of the fermentation of milk which bears some resemblance to kumys. The following table (Table XXIV) gives a comparative view of the composition of true kumys, the same prepared from cows' milk, and kefyr: — 144 TEXT-BOOK OF HYGIENE. Table XXIV. True Kumys Cows' MilkKumys Kefyr (percent.). (percent.). (percent.) Pi'oteids 2.20 2.35 3.12 Fats 2.12 2.07 1.95 Sugar 1.53 1.81 1.62 Lactic acid 0.90 0.40 0.83 Alcohol 1.72 1.90 2.10 CO2 0.85 0.80 0.92 As bearing on the question of intemperance, it may be well to mention that many patent medicines which are largely consumed by the laity for their supposed curative effect owe their virtues to the large amounts of alcohol which they contain. The following is a list of the more popular tonics, analyzed principally by the Massachu- setts State Board of Health : — Table XXV. Alcohol, Per cent. Liebig Company's Cocoa Beef Tonic 23.2 Schenck's Seaweed Tonic, "entirely harmless" 19.5 Atwood's Quinine Tonic Bitters 29.0 Boker's Stomach Bitters 42.6 Burdock Blood Bitters 25.2 Copp's White Mountain Bitters^ "not an alcoholic beverage" . . 6.0 (It should be noticed that this "tonic" contains more alcohol than the strongest beer.) Drake's Plantation Bitters 33.2 Green's Nei-\'ura 17.2 Hoofland's German Bitters, "entirely vegetable and free from alcoholic stimulant" 25.6 Hostetter's Stomach Bitters 44.3 Kaufmann's Sulphur Bitters, "contains no alcohol" _ 20.5 (As a matter of fact no sulphur was found in this prepara- tion.) Paine's Celery Compound 21.0 Walker's Vinegar Bitters, "contains no spirit" 6.1 Warner's Safe Tonic Bitters , . . 35.7 Ayer's Sarsaparilla 26.2 Hood's Sarsaparilla 18.8 Dana's Sarsaparilla 13.5 Peruna 28.0 Warner's Safe Cure 15.60 Kilmer's Swamp Root 10.90 Toneco Stomach Bitters 35.50 Angostura Bitters 50.17 THE ALKALOIDAL BEVERAGES. 145 The dose recommended on the labels is from a teaspoonful to a winegiassful from one to four times a day, "increased as needed." The pure food law recently enacted by our national government requires the amount of alcohol in a medicinal preparation to be plainly stated on the label. Whether this will remove the existing evil of sell- ing alcohol under the guise of medicine remains to be seen. THE ALKALOIDAL BEVERAGES. The virtues of the alkaloidal beverages depend upon certain alkaloids which differ very little in their chemical composition or physiological effects, and upon certain volatile aromatic constituents of the various articles used. The principal articles employed in the preparation of these beverages are coffee, tea, chocolate, mate, and coca. It is estimated that 500,000,000 people drink coffee, 100,000,000 tea, 50,000,000 chocolate, 15,000,000 mate or Paraguay tea, and 10,000,000 coca. All of these are active nervous stimulants and re- tarders of tissue-waste. They are all liable to produce serious func- tional disturbances of the nervous, digestive, and circulatory systems if used to excess. Anaemia, digestive derangements, constipation, pale, sallow complexion, loss of appetite, disturbed sleep, nervous headaches, and neuralgias are the most marked of these effects. On the other hand, when taken in moderate qiTantities, the alka- loidal beverages enable the consumer to withstand cold, fatigue, and hunger; they promptly remove the sensation of hunger, and diffuse a glow of exhilaration throughout the body. Coffee. — Coffee is the ripe fruit (seed) of the Caffea Arabica, a native of i\.rabia and Eastern Africa, but now cultivated in other tropical regions of the world. The fruit consists of two flat-convex beans, the flat surfaces of which are apposed to each other. These are enclosed in a fl1)rous envelope which is sometimes used as a cheap substitute for the coffee-bean. The beverage, coffee, is an infusion of the roasted and ground bean in hot water. Its virtues depend upon the alkaloid, caffein, and an aromatic oil. The latter, being volatile, is driven off by long- continuod heat. Hence boiled coffee lacks the grateful aroma of that which is made by simply infusing the ground bean in hot water. The great demand for coffee and its comparatively high price have caused it to be extensively adulterated and substituted by other natural and artificinl products. Artificial coffee-beans have been made of clay, dough, or extract of chicory, colored to imitate the natural 10 146 TEXT-BOOK OF HYGIENE. bean. The fraud is easily detected by placing the beans in water, when the artificial product soon falls to pieces, while the natural beans undergo no change of shape or consistence. Ground coffee as found in the stores is usually adulterated. The materials used for sophistication are: The grounds of coffee previ- ously used, the roasted root of chicory, acorns, rye or barley, carrots, sun-flower seeds, caramel, and a number of articles of similar value, genei'ally harmless. Tea.- — The plants which furnish the tea-leaves are natives of China, Indo-China, and Japan. The tea-leaves contain a crystalline alkaloid, thein, identical in composition and properties with caffein. The various sorts of tea found in the market (green and black teas, etc.) differ only in the relative proportion of tannin and thein con- tained in each. The aromatic principle also varies somevrhat in the different sorts. Tea is adulterated to quite as great an extent as coffee, the leaves of various plants bearing more or less resemblance to tea-leaves being added to the latter. Much of the tea found in the market is colored artificially with Prussian blue and iron oxide. These addi- tions are harmless, as they are not soluble in water. Chocolate. — Cocoa, from which chocolate is derived, is widely different in composition from tea and coffee. In addition to its ac- tive principle, theobromin, which is identical with caffein, it contains nearly 50 per cent, of fat, which renders it an article of high nutri- tive value. Mate, or Paraguay tea, guarana, and coca are used to a considerable extent in some parts of South America as substitutes for coffee and tea. Their composition is not well known, but their effects are believed to depend upon alkaloidal principles similar to caffein and thein. TOBACCO. Closely connected with the subjects treated in this chapter are the effects of the constant use of tobacco upon the human system. The depressing effects of tobacco, due principally to the nicotine, upon the nervous and digestive systems have long been recognized. Ee- cently, however, it has been found that very serious symptoms are produced upon the sense of vision by the constant or excessive use of tobacco. A special form of amaurosis, termed tobacco amaurosis, has been frequently noticed since attention was first called to it by Mackenzie. ADULTERATIONS OF FOODS. 147 ADULTERATIONS OF FOODS. The adulteration of food-products has received considerable attention of late, no more, however, than the seriousness of the sub- ject demands. There is hardly a food-product which is not sophisti- cated by the unscrupulous manufacturer, and, while most of the adulterants are harmless, many are injurious to health. The follow- ing list from Battershall gives an adequate idea of the common adul- terations. As to the uncommon adulterants, they include such pal- atable substances as sawdust, horseliver, oak-bark, colored earths, fac- tory sweepings, brick-dust, and numerous others which the ingenuity of the manufacturer suggests, and which baffle all efforts at detection, owing to their uncommonness. The regular list, then, includes: — „ , , . f Starch, Bakers chemicals < . , Bread and flour \ ^ther meals, >• Alum. r Water, Butter < Coloring matter, ' Oleomargarine and other fats. ri 1 £ 1 f Metallic poisons. Canned foods < \ ( Preservatives, f Lard, I Oleomargarine, ^^''"^^^ j Cottonseed oil, I Metallic salts. ( Sugar, Cocoa and chocolate < Starch, i Flour. f Chickory, j Peas, Coffee ] Rye, I Corn, • [ Coloring matter. C Starch-sugar, I Starch, Artificial essences, Poisonous pigments, I Terra alba, [ Plaster-of-Paris. Honey /Glucose syrup, <- Cane-sugar. f Artificial glucose, I Bitters, ^■^^^ l^l"*^""^ I Sodium bicarbonate. Salt. Confectionery -| 148 TEXT-BOOK OF HYGIENE. ! Water, Removal of fat, Presen'atives. (Flour, Turmeric, Cayenne pepper. Olive oil (Cottonseed oil, I Other oils. Pepper Various gioimd meals. Pickles Salts of copper. (Pepper dust, Starch, Flour. ' Water, Fusel- oil, ' ^ ' Aromatic ether. Burnt sugar. Sugar Starch-sugar. r Exhausted tea-leaves, Foreign leaves, Indigo, Tea \ Prussian blue. Gypsum, Soapstone, Sand. r Water ^i^^g^^ (sulphuric acid. r Water, w- Spirits, ^^^ ) Coal-tar and vegetable colors, I Factitious imitations. Of 61 samples of milk purchased of milk-dealers in the city of Wilmington and examined by the Delaware State Board of Health Laboratory, 39 contained formalin, 12 were skimmed, 3 were watered, 5 were skimmed and watered, and 2 were suspicious. The superficial observer will probably conclude that adulteration is accidental and irregular; that it depends entirely on the honesty and business integrity of the individual manufacturer. This is far from being the case. Sophistication is an economic factor in the struggle for trade. Cheaper products are demanded by the poor, and cheaper products are supplied; but as the only way to cheapen them is to sophisticate, adulteration is practiced as a bona fide busi- ness measure. As a result, we have fraud reduced to a system; fraud not regulated by conscience or principles; fraud from which the otherwise honest man does not shrink, but, nevertheless, fraud ADULTERATIONS OF FOODS. 149 which robs the poor man of the money he earns by the sweat of his brow. This fact has been clearly brought out by the Senate Committee appointed to investigate the extent and nature of adulteration of foods (Senate Report, Vol. 3, No. 516). "The adulteration of pre- pared or manufactured foods/' says the committee, "is very exten- sively practiced, and in many cases to the great discredit of our man- ufacturers. It is only fair to say, however, that a large proportion of the American manufacturers who are engaged in adulterating food-products do so in order to meet competition, and it is the ex- pression of those gentlemen to say : 'We would be glad to get out of the business of adulterating. We would like to quit putting this stuff in our coffee, and would be willing to brand our syrups for what they are, but our competitors get a trade advantage which we cannot sur- render.' " In a recent report of the Illinois State Pood Commission (1899- 1900) we find the following table of adulterations detected during the year : — Table XXVI. Number Number Article of Food. Analyzed. Adulterated. Baking powder 44 44 Butter 49 36 Catsup 47 45 Cider (apple) 3 1 Cider (orange) 1 1 Coffee 15 Condensed milk (bulk) 4 1 Condensed milk (cans) 22 4 Cream of tartar 11 2 Honey '. 22 9 Jellies, Jams, etc 13 9 Lemon extracts 34 27 Milk 29 5 Olive oil 25 13 Sugar (granulated) 1 1 Vanilla extract 26 20 Vinegar 360 192 Total 712 412 The recently enacted pure food law will remedy the evil of mis- branding so far as interstate commerce goes, but will not prevent adulteration of foods and food-products within the limits of any single State. State legislation will be required to meet these condi- tions in each State. 150 TEXT-BOOK OF HYGIENE. THE EXAMINATION OF FOOD. It wonld be manifestly inadvisable to attempt to detail tlie methods for the determination of the purity and healthfiilness of the many articles of food that make up the daily dietaries of the people at large; but since occasions are constantly arising when it is desir- able to laiow something of the condition of certain food-stufPs which are used by practically every one, and which are especially liable to sophistication or adulteration, the following notes are, therefore, added as being within the scope of the chapter: — Milk. — Good milk shoukl be ivory-white in color, opaque, of neutral or slightly-alkaline reaction, and should have no sediment nor any unusual taste or odor. The specific gravity should be 1029 or above; the proportion of cream, from 10 to 40 per cent, by volume; the fats, 3 per cent, or more, and the total solids 12.5 per cent, or more. The number of bacteria should not exceed 500,000 per cubic centimetre. The color is enriched by a high percentage of cream, but too rich a color or one with a reddish or yellowish tint may indicate the addition of annatto. A poor color indicates that the milk is deficient in fat, and may be due to skimming or watering, or both, but a pecu- liar blue color is sometimes produced by the growth of a certain fungus in the milk. The lessening of fat also tends to make the milk trans- lucent and less opaque. An acid reaction, unless very slight, indicates "souring" of the milk or the addition of some preservative, such as salicylic or boric acid ; while a strongly-alkaline reaction points to the addition of some substance like chalk, sodium carbonate, etc., to increase the specific gravity. Such addition is verified by a high percentage of total solids and by the effervescence of the latter upon the addition of a drop or two of hydrochloric acid. The specific gravity is determined by means of the lactometer, in using which corrections must be made for the temperature if the latter varies much from 60° F., the standard. The specific gravity is slightly raised by skimming the milk, since the cream is lighter than the whole milk, and, theoretically, a very high percentage of cream tends to lower the specific gravity; but, in reality, a milk rich in cream is also rich in other solids that keep the specific gravity high or, at least, normal. The percentage of cream is determined by the creamometer, THE EXAMINATIUX OF FOOD. 151 which should be covered and in which the milk should stand for eight or ten hours. The principal sophistications of milk are by watering, skimming, the addition of solids to increase the specific gravity or to act as pre- servatives or to mask "souring," and the addition of annatto and the like to enrich the color. "Watering is indicated by a low specific gravity and by a low percentage of cream and of total solids. Skim- ming is indicated by a low percentage of cream and poor color, though the latter m^ay be disguised by the addition of annatto, etc. The spe- cific gravity will be very slightly raised by the skimming, but if the milk has been both skimmed and watered the density will be lowered. To Determine the Percentage of Total Solids. — Weigh a small evaporating dish, preferably platinum. Add 5 or 10 c. c. of milk, and weigh the dish and milk to get the weight of milk. Evaporate to dryness over a water-bath, completing the drying in a water-oven until there is no further loss of weight. Weigh the dish and contents (total solids) ; subtract the weight of dish and divide by the weight of milk. The result is the percentage of total solids. To Determine the Percentage of Ash. — Ignite the tctal solids over the naked flame until all black specks have disappeared. Cool and weigh. Divide the weight of ash by weight of milk. The result is the percentage of ash. To Determine the Percentage of Fats. — Proceed as above with 10 c. c. of milk and evaporate till the residue is a tenacious pulp. Extinguish the flame, fill the dish half-full of ether, and stir and pound the residue thoroughly with a glass rod ; filter through a small filter- paper, reserving the filtrate ; add more ether to the residue, stir as before and filter, repeating the process three times, or till the residue is perfectly white. Wash filter-paper well with ether, and evaporate all the ether to dryness. Weigh the residue (the fat) and divide by the weight of milk. Eesult : percentage of fat. The fat can be more conveniently determined by the use of the Babcock tester. This is a centrifugal machine holding two or more graduated bottles especially made for this purpose. The test is performed as follows : Measure 17.6 c. c. of milk and an equal quantity of strong sulphuric acid (sp. gr. 1.82) and pour into the bottle. Mix by shaking gently until curd dis- solves. Place in centrifuge and revolve at 1000 revolutions per min- ute for five minutes. Pill the bottles to the highest graduation with hot water and whirl for one minute longer. Ecad on the scale the space occupied by the column of fat which rises to the top. The lower margin of this column indicates the percentage of fat. 152 ■ TEXT-BOOK OF HYGIENE. Test for Annatto. — A percentage of cream considerably lower than color of milk would indicate justifies the suspicion that some coloring matter has been used. This is generally annatto. Coagulate one ounce of milk with a few drops of acetic acid, and heat ; strain and press out excess of liquid from curd. Triturate the curd in a mortar or dish with ether. Decant the ether and add to it 10 c. c. of a 1- per-cent. solution of caustic soda. Shake and allow to separate; pour off the upper layer into a porcelain dish. Put in two small discs or strips of filter-paper. Evaporate gently; annatto will dye the discs an orange or buff color. Moisten one disc with dilute sodium carbon- ate to fix the color. Touch the other disc with a drop of stannous chloride ; annatto will give a rich pink color. This test is sensitive to 1 part of annatto in 1000 of milk, and with milk in any condition. Detection of Cane-sugar in Milk and Cream. — Mix 15 c. c. of milk or cream with .1 gram resorcin and 1 c. c. cone, hydrochloric acid and heat to boiling. In presence of cane-sugar a fine red color is pro- duced, while pure milk turns brownish; 0.2 per cent, can thus be de- tected. Levulose gives the same reaction, but glucose does not. Test for Boric Acid. — In igniting the total solids, boric acid, or boron, gives a greenish tinge to flame. Place in a porcelain dish one drop of milk, two drops of strong hydrochloric acid, and two of sat- urated tincture of turmeric. Dry on a water-bath, remove as soon as dr}^, cool and add one drop of ammonia on a glass rod. A slaty-blue color, changing to green, is given if borax is present. This test will show ^/looo grain of borax. Less will give the green color, but not the blue. Formaldehyde. — The milk is diluted with an equal volume of water. Sulphuric acid containing a trace of ferric chloride is added so that it forms a layer beneath the milk. Under these conditions, milk, in the ahsence of formaldehyde, gives a slight greenish tinge at the juncture of the two liquids, while a violet ring is formed when formaldehyde is present even in so small a quantity as 1 part in 200,- 000 of miik. Sodium Carhonate. — Ten c. c. of milk are mixed with an equal volume of alcohol and a few drops of a 1-per-cent. solution of rosolic acid added. Pure milk shows merely a brownish-yellow color, but in the presence of sodium carbonate a more or less marked rose-red ap- pears. This test is made more delicate by using a comparison cylin- der containing the same amount of milk known to be pure. Butter. — Good butter should have a good taste, odor, and color; it should not be rancid, and should not contain too much salt, nor THE EXAMINATION OF FOOD. 153 should it have any added coloring matter. The average composition should be about as follows : Fat, 82 per cent. ; casein, 2 per cent, (not over 3 per cent.) ; ash or salts, 2 per cent.; water, 13 per cent.; milk-sugar, 1 per cent. Butter-fat is a compound of a glycerine with certain fatty acids, some of them volatile and soluble in hot water, others non-volatile and insoluble in hot water. Oleo-margarine consists of ordinary animal (or vegetal^le) fats melted, strained, cooled with ice, worked up with milk, colored, and salted. These fats are usually beef or mutton, lard or cotton-seed, palm- or cocoa-nut- oil. If care and cleanliness are observed in the manufacture, oleo-margarine is not harmful or innutritions, but it should not be sold as butter. Fraud is to be detected by observing the difference in composition and properties of the fats. The following talkie, from Kenwood^s "Hygienic Laboratory," will show the characteristic difference in the fats : — Butter-fat. Beef-fat. 1. The specific gravity is very Is never above 904.5. rarely below 910, never below 909.8. 2. The soluble, volatile fatty acids Rarely more than Vs per cent.; average between 6 and 7 per cent, never above % per cent. never below 4.5 per cent. 3. The insoluble fatty acids form Generally about 95 per cent, about 88 per cent, of the total weight of butter-fat. 4. The melting-point of the fat Earely, if ever, above 82° F. varies from 86° to 94° F. ; is usually from 88° to 90° F. 5. Is readily and completely soluble Less so, and leaves a residue, in ether. 6. Under the microscope pure but- The contours of the small oil-glob- ter consists of a collection of small ules are less distinct, and the larger oil-globules' with an occasional large ones are more numerous and irregular one. No crystals, except when the in size. Crystals of the non-volatile fat has been melted. acids are often seen. To Determine the Specific Gravity. — ]\Ielt a quantity of the but- ter in a beaker on a water-bath at about 150° F. After a time, when the fat is perfectly clear and transparent, carefully decant from the lower stratum of water, curd and salt on to a fine filter; collect the filtrate and pour into a specific-gravity bottle, which has been previ- ously weighed, both when empty and when filled with water at 100° F. See that the bottle is exactly full of the fat; wipe clean and weigh when the temperature is as near 100° F. as possible, because solidifica- 154 TEXT-BOOK OF HYGIENE. tion soon begins at this temperature. Subtract tbe weight of the bottle, divide>by the weight of the water, and multiply by 1000. The result is the specific gravity. To Find the Melting-point. — Pour a little melted fat into a small test-tube (2"x^/^"). Partly fill two beakers of unequal size with cold water; place the test-tube in the smaller (taking care to allow no water to mix with the fat), and the smaller in the larger, and gently heat the outer beaker. Suspend a thermometer in the smaller, near the test-tube, and note the temperature when the fat begins to melt. This is the melting-point. To Determine the Percentage of Insoluble (Non-volatile) Fatty Acids. — To 5 grammes of butter-fat add 50 c, c. of alcohol contain- ing 2 grammes of caustic potash (KHO) and boil gently for fifteen or twenty minutes to saponify the fat. Dissolve the soaps thus formed in 150 to 200 c. c. of water and decompose with about 25 c. c. of dilute hydrochloric acid. The separated fatty acids are collected upon a weighed filter-paper, washed with 2 litres of boiling water, dried at 95° to 98° C, and then weighed. The weight of these insoluble fatty acids should not be over 90 per cent, of the weight of the butter-fat. Flour and Bread. — Wheat-flour should be almost but not per- fectly white, also smooth and free from grit; it should have no moldy or unpleasant odor, and, imless made by the new process, should be cohesive when lightly compressed in the hand. There should be no signs of parasites or fungi under the microscope. The proportion of gluten should be more than 8 per cent. ; of water, less than 18 per cent., and of ash, less than 2 per cent. To Determine the Percentage of ^Yater and Ash. — In a weighed platinum (or porcelain) dish place about 50 grammes of fl.our, weigh and dry over a water-bath for an hour or so ; then complete the evap- oration in a water-oven until there is no further loss of weight; weigh, subtract this weight less the weight of the dish from the orig- inal weight of the flour. The result is the percentage of water. Then igTiite the dried flour in the dish and incinerate till there are no longer any black particles and only the ash remains ; cool, weigh, and divide by the original weight of the flour. The result is the per- centage of ash. To Determine the Percentage of Gluten. — By means of a glass rod, mix a weighed quantity of flour with a little distilled water into a stiff dough ; then repeatedly wash away the starch and soluble con- stituents, kneading the dough with the rod or fingers and continuing "until the wash-water comes away clear; the gluten and a small amount THE EXAMINATION OF FOOD. 155 of fat and salts remain. Spread out on a weighed dish or crucible-lid, dry in a water-oven, and weigh. Divide by the original weight of the flour. The result is the approximate percentage of gluten. The gluten should pull out in long threads, otherwise it is poor. An excess of water impairs the keeping-quality and lessens the amount of nutriment in the flour. An excess of ash indicates the addition of mineral substances. A deficiency of gluten indicates that the flour is not pure wheat-flour. Parasites and fungi especially affect or live in old or damp and inferior flour. To Test for Mineral Substances. — Shake a little flour in a test- tube with some chloroform, and allow it to stand for a few mo- ments. The flour floats and any mineral matter sinks to the bottom, when it can be removed with a pipette and examined under a micro- scope. Wheat-bread should be fairly dry, light, and spongy; clean and nearly white; of pleasant taste; not sodden, acid, or musty; no parasites or moldiness. It should contain no flour other than wheat; but little, if any, alum; no copper sulphate; and should not yield over 3 per cent, of ash. Test for Alum. — Add 5 c. c. of a 5-per-eent. tincture of logwood and 5 c. c. of a 15-per-cent. solution of ammonium carbonate to 35 c. c. of water ; soak a crumb of the bread in this for a few minutes ; drain and gently dry. Alum is indicated by a violet or lavender color, its absence by a dirty-brown color on drying. Test for Copper Sulphate. — Draw a glass rod dipped in a solution of potassium ferrocyanide across a cut slice of the bread; copper is indicated by a streak of brownish-red color. Test for Ergot in Flour or Bread. — Add liquor potassse; a dis- tinct, herring-like odor (due to propylamine) is appreciable if ergot be present. An excess of water, an unnatural whiteness, and a low percentage of ash in bread indicate the addition of rice. Potatoes give an in- creased percentage of water and an alkaline ash. QUESTIONS TO CHAPTER III. FOOD. What is a food? What reasons have we for stating that the proximate food principles must be combined in definite proportions to maintain a normal degree of health? What are the alimentaiy principles necessary to man's existence? Why do we need water? What are the functions of the salts in our foods? Is existence possible without a sufficient supply of nitrogenous food? What is the relation of starch to fat as oxidizable food? Are the proteid tissues of the body derived solely from the nitrogenous foods? \^Tiat are the sources of the body-fat? What tissues are mostly con- sumed during work? What is the relation between the proximate food principles, and what amount of each is necessary in the standard daily diet of a man at rest? At moderate labor? At hard work? About what is the relation of nitrogenous to non-nitrogenous food? Of nitrogen to carbon? Is a standard diet neces- sarily an expensive one? How may it be selected? What is a' calorie? Whj is a variety in the kind of food necessary? Why may not a man live on nitrogenous foods, like meat, alone? Why not on non-nitrogenous food, like potatoes? Has climate much influence upon the amount of food needed? Has it upon the kind of food? What kind of food is especially beneficial for a labor- ing man in cold weather? Where do we find the proteid principles of food? Where the fatty? Where the carbohydrates? The salts? Why should only a moderate amount of food be taken, and why should it be properly prepared? What are some of the factors that increase the consumption of carbonaceous foods? Does increased physical labor increase the demand for nitrogenous foods? Which requires the most carbonaceous food, physical or mental labor? What maladies especially require fat-producing foods? Has the food that a man eats anything to do with his moral character? How may we classify food? Name some of animal origin. From the vegetable kingdom. What is the function of condiments? Of stimulants? Why is milk so nearly a perfect food? "Wliat is the average composition of cows' milk? "\^Tiat is the difference between human milk and cows' milk? What other substitutes are sometimes used for human milk? What is cream? What changes take place in milk upon standing for some time? To what are these changes due? What is made from the curd? Has whey, or butter-milk, any food value? What should be the specific gravity of milk? How is it determined? What may lower the specific gravity? 'VSTiat may raise it? Has "skim-milk" a food value? What is the objection to its sale? (156) QUESTIONS TO CHAPTER III. 157 How is milk frequently adulterated? How may this be detected? Why is the addition of water dangerous? How else might the milk become in- fected? May infectious diseases be transmitted from the cow to man through the milk? How may this danger of infection be avoided? What diseases are especially likely to be thus conveyed by the milk? Give an account of the "Hendon cow disease." May the milk of animals suffering from certain febrile diseases be dangerous to health? Is the milk of cows fed on distillery or breweiy refuse necessarily unwholesome? How may the quality of a milk be determined? What is a lactoscope? What is a creamometer? What, should be the minimum percentage of cream? How may the rapid fermentation of milk be prevented? What is tyrotoxicon, and to what is it due? What is butter? What is its food value, and why? What change does it undergo in becoming "rancid"? How is it often sophisticated? What is oleo-margarine or butterine? How is it made? Is it unwholesome, and is there any objection to its use if sold under its proper name? Upon what does the value of cheese depend? Is it nutritious? Why cannot large quan- tities be eaten at a time? What are the richest kinds of cheese? Is cheese often adulterated? How may cheese be made more digestible? What dangerous change may it undergo, and to what is this due? Why is meat such an important article of food? What is the percentage of proteids and fats in the meats commonly used? Upon what does the varia- tion between these two principles depend? Should meat be cooked and eaten immediately after death? Should it be kept too long after death before being used? Why should meat be always cooked? \Vhat are the common methods of cooking? Are beef-extracts really nutritious? Are partially or wholly pre- digested preparations of meat nutritious? What is the objection to their continued use? What conditions may render meat unfit for food? How may the various parasites in meat be destroyed? What animals are apt to be infested with trichinae? In what two forms are the trichinae found in animals? How do they gain access to the muscles? May salted or smoked meat contain living trichinae? Of what parasite is the Cysticercus cellulosa a transition form? What may be the result of using partially-decomposed meat or fish? To what are the serious results due? How are the ptomaines produced? What is their probable chemical nature? What peculiar idiosyncrasy have some people regarding shell-fish? What infectious diseases may be transmitted to human beings by the consumption of infected meat? When and by whom should meat be inspected? Wliy are eggs so highly valued for food ? In which form are eggs most digestible? Why do eggs undergo putrefaction so readily? What cereals are used in making bread? What part of the grain con- tains the greater proportion of proteids? Is all the gluten to be found in the 158 TEXT-BOOK OF HYGIENE. bran? Which flours are most nutritious and which most digestible? What are some of the characteristics of good bread? To what is the porosity due, and how is it produced? How may the loss of starch by fermentation be avoided? How is flour often adulterated? Why is alum added to flour? What disease of grain may be harmful to the health of the users? What is the chief constituent of potatoes and rice? In what principle are the leguminous foods especially rich? Wherein is the chief value of green vegetables? Wliy are fruits and nuts valuable as articles of diet? What rule should be observed regarding the use of condiments? Why should physicians know considerable about cooking? "What are the various methods of cooking? What is the eflect of boiling upon meats? What points are to be observed in the boiling of meat? In the making of soups, etc.? What valuable principle is lost if vegetables are boiled too long? What is the secret in making good coflee? What is frying? How should it be done? How should meats be roasted? Why are broiling and baking gen- erally satisfactory processes? Into what two classes may alimentary beverages be divided? For what are those of the second class used? What is the physiological effect and action of alcohol upon the nerve-centres? Upon the circulation? Is it changed before absoi-ption? Does it nourish the body? Does it supply heat? Does it raise the body-temperature? What effect has it on heat-production and heat-radia- tion? On tissue v/aste? How^ is it excreted? What eff"ect have small amounts of alcohol upon digestion? What pathological changes are brought about by the constant use of alcohol? Is it necessary or beneficial to persons in good health? Why is it so valuable in fevers and wasting diseases? Does it enable persons to withstand fatigue ? To what diseases is the predisposition increased by the habitual use of alcohol? What eff"ect has it upon the expectation of life and upon the mortality from various diseases? If used habitually, what forms should be chosen? What is the difference between spirits, wines, and malt liquors? "SATiat is brandy? From what is whisky made? How much alcohol do the various spirits contain, and what rule should be observed re- garding their use? What percentage of alcohol do the various wines contain? Which are the least objectionable for habitual use? What can be said regard- ing the domestic wines? To what disturbances may cider give rise, and why? From what articles alone should beer be made? How much alcohol should it contain? With what substances is it often sophisticated? Have beer, ale, etc., a dietetic value, and why? What may be the result when beer is used to excess? What are kumys and kefyr? Why are they valuable in sickness? How much alcohol does each contain? Upon what do the virtues of the alkaloidal beverage depend? '\^Tiat are the principal articles employed in their preparation? What is the physiological action of all these substances? "Wliat are some of the effects if they are used to excess? What is their effect when used in moderation? May they be used as substitutes for alcohol? What is coffee, and what alkaloid does it contain? What else does it contain that gives value to the beverage? How is coffee adulterated, and how may fraud be detected ? What is tea, and what alkaloid does it contain ? How may it be adulterated? Why is cocoa of greater food value than tea or QUESTIONS TO CHAPTER III. I59 coffee? What is its active principle, and what is its relation to thein and caffein? What is the difference between cocoa and chocolate? What are the effects of tobacco upon the human system, and to what are they due? What are some of the characteristics of good milk? What may affect its color? Its reaction? Its specific gravity? How is it usually sophisticated or adulterated? How is the percentage of total solids determined? Of fats? V\^hat would a high percentage of ash indicate ? Give a test for annatto. For boric acid. For formaldehyde. What are the characteristics of good butter? What is the difference between it and oleo-margarine and similar compounds? What tw^o kinds of fatty acids does butter-fat contain? What are some of the distinctions be- tween butter-fat and beef-tea or mutton-fat? Plow is the specific gravity of butter-fat determined? The melting-point? The percentage of insoluble fatty acids? What are some of the properties of good wheat-flour? Of wheaten bread? How is the percentage of gluten in flour determined? The presence of added mineral substances? What does a low percentage of gluten indicate? In what kind of flour are parasites, etc., found? What is a test for alum in bread? Should bread contain any alum? What flours or starches may be used to sophisticate wheat-flour? CHAPTER IV. SOIL. Hippocrates treated at length, in one of his works, of the sani- tary influences of the soil. Others of the older writers, especially Herodotus and Galen, called attention to the same subject, and Vitru- vius, the celebrated Eoman architect, who flourished at the beginning of the Christian era, taught that a point of first importance in build- ing a dwelling was to select a site upon a healthy soil. From this time until the beginning of the eighteenth century, very little of value is found in medical literature bearing upon this subject. In 1717, however, Lancisi published his great work on the causes of malarial fevers, in which he laid the foundation for the miasmatic theory of malaria, and pointed out the relations existing be- tween marshes and low-lying lands and those diseases by common consent called malarial. Other authors of the eighteenth and the early part of the nineteenth centuries refer to the connection be- tween the soil and disease, but exact investigations have only been made within the last thirty years. When it is considered that the air that human beings breathe, and much of the water they drink, are influenced in their composi- tion by the matters in the soil, the great importance of possessing a thorough loiowledge of the physical and chemical conditions of the soil becomes evident to every one. PHYSICAL AND CHEMICAL CHARACTERS OF THE SOIL. In the hygienic, as in the geological sense, rock, sand, clay, and gravel are included in the consideration of soils. The soil, as it is presented to us at the surface of the earth, is the result of long ages of disintegration of the primitive rocks by the action of the elements, of the decomposition of organic remains, and, possibly, of accretions of cosmical dust. The principal factor, how- ever, is the action of water upon rock, in leveling the projections of the earth's surface produced by volcanic action. Soils vary considerably in physical and chemical constitution. A soil may, for example, consist exclusively of sand, of clay, or of (160) THE ATMOSPHERE OF THE SOIL, OR GROUND-AlR, 161 disintegrated calcareous matter. Other soils may consist of a mixture of two or more of these, together with vegetable matter undergoing slow oxidation. In forests, a layer of this slowly-decomposing vege- table matter of varying thickness is found, covering the earthy sub- stratum. This organic layer is called humus, and when turned under by plough or spade, and mixed with the sand or clay base, it con- stitutes the ordinary agricultural soil. THE ATMOSPHERE OF THE SOIL, OR GROUND=AIR. The interstices of the soil are occupied by air or water, or by both together. The soil's atmosphere is continuous with, and resem- bles in physical and chemical properties, that which envelops the earth. Its proportion to the mass of the soil depends upon the de- gree of porosity of the soil, and upon the amount of moisture pres- ent. In a very porous soil, such as, for example, a coarse sand, gravelly loam, or coarse-grained sandstone, the amount of air is much greater than in a claj^ey soil, granite, or marble. So, likewise, when the soil contains a large proportion of water, the air is to this extent excluded. The porosity of the various soils, as evidenced by the amount of air contained in them, is much greater than would, at first thought, be supposed. Thus, it has been found that porous sandstone may contain as much as one-third of its bulk of air, while the pro- portion of air contained in sand, gravel, or loose soil may amount to from 30 to 50 per cent. The ground-air is simply the atmospheric air which has pene- trated into the interstices of the soil and taken part in the various chemical decompositions going on there. In consequence of these chemical changes the relative proportions of the oxygen and car- bonic acid in the air are changed — oxygen disappearing and giving place to carbon dioxide. It is well known that during the decay of vegetable matter in the air carbon dioxide is formed; one constituent of this compound, the carbon, being derived from the vegetable matter, while the oxygen is taken from the air. Hence, if this ac- tion takes place where there is not a free circulation of air, as in the soil, the air there present soon loses its normal proportion of oxygen, which enters into combination with the carbon of the vegetable matter to form carbon dioxide. Over thirty years ago, MM. Boussingault and Levy, two distin- guished French chemists, examined the air contained in ordinary- agricultural soil, and found that the oxygen was diminished to about 11 162 TEXT-BOOK OF HYGIENE. one-half of the projDortion normally present in atmospheric air, while the carbon dioxide was enormously increased. The exact results obtained by Boussingault and Levy were as follows : — In 100 volumes of ground-air there were 10.35 volumes of oxy- gen, 79.91 volumes of nitrogen, 9.74 volumes of carbon dioxide. In atmospheric air, on the other hand, there are in 100 volumes 30.9 vol- umes of oxygen, 79.1 volumes of nitrogen, 0.04 volume, or about ^/2,5 of 1 per cent, of carbon dioxide. In spite of the striking results obtained by these two chemists, very little attention was paid to them by sanitarians, as very few seemed to have any clear notion of the relations existing between the motions of the air above ground and that under ground. In 1871, however. Professor von Pettenkofer, of Munich, pub- lished the results of his own examinations into the constitution and physical conditions of the ground-air, and the relations of the latter to the propagation of epidemic diseases. These researches, which created a widespread interest in the sul^ject, were extended by other Qbservers in all parts of the world. These observers, prominent among whom were Professors Fleck, Fodor, and Soyka, in Germany; Drs. Lewis and Cunningham, in India ; Professor William Eipley Nichols, in Boston; and Surgeons J. H. Kidder and S. H. Griffith, of the U. S. Navy, in Washington, demonstrated that the increase of carbon dioxide in the ground-air is due to increased vegetable decomposition and to lessened permeability of the soil. A permeable, that is to say, a sandy or gravelly soil is likely to contain less carbon dioxide in its atmosphere than a dense, less permeable clay, although the amount of decomposition going on and the production of carbon dioxide in the former may considerably exceed tbe latter. In the loose, sandy soil the circulation of the air is less obstructed, and the carbon di- oxide may easily escape and be diffused in the superincumbent air, while the close-pored clay imprisons the carbon dioxide and pre- vents or retards its escape into the air above. The disappearance of oxygen from the ground-atmosphere is coin- cident with the production of an equivalent amount of carbon dioxide. It appears from this that in the soil an oxidation of carbonaceous substances takes place, the product of which is found in the excess of carbon dioxide in the ground-air. Professor Nichols has found the proportion of carbon dioxide in the air taken from a depth of 3 metres below the surface in the "made-land" of Boston to amount to 21.21 per thousand, the obser- vation having been made in August. In December, at a depth of 2 THE ATMOSPHERE OF THE SOIL, OR GROUND-AIR. 163 metres, the proportion was 3.23 per thousand. Fodor, in Buda- Pesth, found the proportion of carbon dioxide to be 107.5 per thou- sand (over 10 per cent.), the air having been taken from a depth of 3 metres. The ground-air also teems with micro-organisms of various kinds, these being occasionally pathogenic. While in the great majority of instances the micro-organisms found are ordinary mold or fermen- tation fungi and bacteria of decay and putrefaction, disease-produc- ing bacilli have also been observed in a number of instances. Among the latter are the bacillus of tetanus (Nicolaier), of anthrax (Frank), of malignant edema (Koch and Gaffky), and of typhoid fever (Tryde) . It may not be inappropriate to refer here to the claim of Pro- fessor Domingos Freire, of Brazil, to the discovery of the germ of yellow fever in the soil of a burial ground near Eio Janeiro. The exhaustive investigations of Surgeon-General G. M. Sternberg, of the U. S. Army, under the direction of the government, have disposed effectually of the claims and pretensions of the Brazilian scientist, and established the fact that Freire's organism has no pathological significance whatever— at all events, that it has no relation to yellow fever. Cholera bacilli have not been found in the soil, but C. Frankel has shown experimentally that they can grow and multiply in the soil at various depths. At a depth of 1^/, metres their development was constant and progressive throughout the year. With regard to ty- phoid bacilli, Houston found that under ordinary condition they die out in the course of a few days to a few weeks. When the soil is dry, these organisms may be carried hither and thither in the movements of the ground-air, and thus be transported to a distance. Movements of the ground-atmosphere are principally due to dif- ferences of pressure and temperature in the air above ground. Owing to such differences the air from the soil frequently permeates houses, entering from cellars or basements. In winter, when the air of houses is very much more heated (and consequently less dense) than the air out-of-doors, the difference of pressure thus caused draws the ground- air up through the house, while the cold, external atmosphere pene- trates the soil and occupies the place of the displaced ground-air.^ A similar effect occurs in consequence of heavy rains. The water fills ' Tt is, of course, not strictly correct to say thnt tTie air is drnivn tip throuf^h the house by the diminution of pressure; it being rather forced out of the soil bv the colder and denser outside air; but the phrase is sufficiently exact and will be readily understood. 164 TEXT-BOOK OF HYGIENE. up the interstices of the soil near the surface, and forces the ground- air out at points where the pores remain open. These places are the dry ground under buildings, where the air escapes and passes through floors and ceilings into the house above. Heavy rains may thus be the cause of pollution of the air in houses. The greater the porosity of the soil, the more likely is this to happen. This pollution of the house-air may be prevented by having impervious floors and walls to cellars and basements, or by interposing a layer of charcoal between the ground and the floor of the house. The latter does not prevent the passage of the ground-air, but the charcoal layer absorbs or arrests the noxious matters — filters the ground-air, as it were. In the spring and early summer the ground being colder than the air above it, and the ground-air consequently heavier and denser, the latter is not easily displaced. It is, perhaps, due to this fact that those infectious diseases which are probably dej)endent upon the movements of the ground-air are less prevalent in the spring and early summer than in the latter part of the summer, autumn, and early winter. In the autumn the ground-air being warmer than the air above ground is easily displaced by the latter and forced out into the streets and houses to be inspired by men and animals. The colder outside air penetrates the interstices of the soil and forces out the impure ground-air. The researches of Fodor have demonstrated that the propor- tion of carbon dioxide in the ground-air may be taken as an approxi- mate measure of the impurity of the soil whence the air is taken. The influence of the permeability of the soil, as before pointed out, must, however, not be overlooked in estimating the signification of the carbon dioxide. Fodor has sho^\Ti that the proportion of carbon dioxide in the ground-air, and consequently the amount of organic decomposition, is greatest in July and least in ]\Iarch. That the car- bon dioxide is derived from the decomposition of vegetable matter has been proven by Pettenkofer. This observer examined specimens of air brought from the Lybian desert, and found that the propor- tion of carbon dioxide in the ground-air Avas exactly the same as in the air collected above ground. There being no vegetable growth in the desert there can, of course, be no vegetable decomposition going on in the soil. The excess of carbon dioxide in the ground-air is an indication of the deficiency of oxygen, as has been sho^^Ti. The air at a depth of 4 metres below the surface was found to contain only from 7 to 10 per cent, of oxygen — one-half to one-third of the normal proportion. THE WATER OF THE SOIL, OR GROUND-WATER. 165 Many basements occupied by people as living-rooms extend from 1 to 3 metres underground, and hence are liable to be supplied with an atmosphere approaching in impurity that just mentioned. It requires no very vivid imagination to appreciate the dangers to health that lurk in such habitations. THE WATER OF THE SOIL, OR GROUND=WATER. At a variable depth below the surface of the ground, a stratum of earth or rock is found through which water passes with difficulty, if at all. Above this there is a stratum of water which moves from a higher to a lower level, and which varies in depth at difEerent times according to the amount of precipitation (rain- or snow- fall), and according to the level of the nearest body of water toward which it flows. This stratum of water is termed ground-water, and has within the last few years assumed considerable importance from its appar- ently close relation to the spread of certain of the infectious diseases. The direction of horizontal flow of ground- water is always toward the drainage-area of the district. Thus, it is usually toward lakes, rivers, or the sea. Eains, or a rise in the river, cause a rise in the ground-water, while long-continued dry weather, or a low stage of the river which drains off the ground-water, causes a fall in the latter. On the sea-coast the ground-water oscillations probably correspond with the tides. The writer is not aware of any observations made to determine this point, with the exception of a single instance men- tioned by Dr. De Chaumont. In Munich, where the ground-water flows toward the river Isar, which divides the city, it has been found that the annual range or oscillation (the difference between the high- est and lowest level during the year) is about 3 metres, while the horizontal movement amounts to 5 metres per day. In Buda-Pesth the annual range was found by Fodor to be less than 1 metre, while in some portions of India it amounts to more than 12 metres. As it is from the ground-water that the greater portion of the supply of drinking-water in the country and in villages and small towns is drawn, it becomes at once manifest how important it is to prevent, as far as possible, pollution of this source. Cess-pools and manure-heaps and pits, of necessity, contaminate the soil and also the ground- water for a distance below and around them, and such water is clearly unfit for drinking and other domestic purposes. Hence, the reason why wells should not be placed too near privies and manure- heaps or pits becomes apparent. 166 TEXT-BOOK OF HYGIENE. Between the level of tlie ground-water, or that portion of the soil where its pores are entirely occupied by water — where, in other words, the ground is saturated — and the surface, is a stratum of earth more or less moist; that is to say, the interstices of the soil are partly filled with water and partly with air. It is in this stratum that the processes of organic decay or putrefaction are most rapidly going on, in consequence of which the pollution of the ground-air occurs. The oxidation of non-nitrogenous matter in the soil results in the forma- tion of carbon dioxide. On the other hand, nitrogenized compounds are oxidized into nitric acid and nitrates. When, however, putrefac- tion occurs, nitrous acid, or nitrites and ammonia, are formed, the oxidation not proceeding far enough to result in nitric acid. Eecent observations seem to show that these processes of decom- position are initiated and kept up by hacteria, just as fermentation in liquids containing sugar can only take place in the presence of the yeast-plant. It has been found that when non-putrefactive decompo- sition goes on, there are always present multitudes of one variety of these minute organisms; while if putrefactive decomposition is going on, a number of other varieties of these organisms are present. Just as, when a fermenting liquid becomes putrid, the yeast-plant disap- pears and its place is taken by the ordinary bacteria of putrefac- tion, so in the soil, if the access of oxygen, which is necessary to the life of the bacteria of decay, is prevented, these organisms die and are succeeded by the organisms of putrefaction. It has been found that in a soil saturated with water the bacteria of decay cannot live, while those of putrefaction may flourish, because these latter organ- isms can sustain life and develop in the absence of oxygen. Professor Fodor's researches indicate that the most prominent organism of non- putrefactive decomposition or decay is that which is termed by Cohn hacterium Hneola; and that the hacterium termo is the principal organism of putrefaction. DISEASES SPREAD BY SOIL IMPURITIES. Given now an area of soil, say the ground upon which a house or city is built, with a moist stratum in which the processes of decay are active, and imagine a rise in the ground-water. The ground-air, charged with carbon dioxide and other products of decomposition, is forced out of the pores of the soil by the rising ground-water, and escapes into the external air, or through cellars and basements into houses, and may there produce disease. But the saturation of the DISEASES SPREAD BY SOIL IMPURITIES. 167 soil with water prevents the further development of the bacteria of decay, and this is checked, or putrefaction may take place. If now the ground-water sinks to its former level or below, the processes of decay again become very active in the moist stratum, and large quantities of carbon dioxide and other inorganic compounds are produced. If the germs of infectious or contagious diseases have been introduced into the soil, they also multiply and, by gaining access to the well or stream from which the drinking-water is obtained, they may cause infection. Professor De Chaumont has laid down the rule that a soil with a persistently low stage of ground-water, say 5 metres below the surface of the ground, is healthy; a persistently high stage of ground-water, less than 1 V2 metres below the surface, is unhealthy ; while a fluctuating level of the ground-water, especially if the changes are sudden and violent, is very unhealthy. This would lead us to expect that places where this fluctuation is very great would show a large mortality from such diseases as are attributed to impurities in the soil. And this we find especially true in India. In certain local- ities in India, cholera, for example, is endemic; that is to say, the disease is never entirely absent in such localities. Calcutta is one of these places. The rainy season begins about the first of May and con- tinues until the end of October. During the next six months there is very little rain. It is fair to assume that the ground-water rises during the rainy season and checks decay and the multiplication of the germs of the disease in the soil, and that these processes become more active as the dry season advances and the ground-water level falls. If we note the death-rate from cholera in Calcutta it will be found that it bears a distinct relation to the movement of the ground- water. The deaths from cholera begin to increase from October and reach their height in April. Dr. Macpherson, who has written a very elaborate history of Asiatic cholera, shows this relation very clearly. For twenty-six years the average rain-fall was 157 centimetres. From May to October 142 centimetres fell, while the remaining 15 centi- metres fell from November to April. The average number of deaths from cholera annually was 4013. Of these, 1238 died in the rainy season, while 2775, nearly three-fourths, died during the period of dry weather. In the cholera epidemics of 1866 and 1873 in Buda-Pesth, the same relations existed between the ground-water and the cholera. As the level of the ground-water rose the cholera diminished, while the disease increased upon tlie sinking of the ground-water. Exactly the same behavior was exhibited by the disease in Munich in 1873. 168 TEXT-BOOK OF HYGIENE. There seems good reason to believe that typhoid fever bears some relation to the movements of the ground-water in the same way as above explained for cholera. Pettenkofer, Buhl, and Virchow have shown that the death-rate from typhoid fever has a distinct and definite relation to the ground-water oscillations. This has been in- contestably proven for two cities, Munich and Berlin. When the level of the ground-water is above the average, typhoid fever de- creases; when it is below the average, the number of cases becomes greater. Dr. H. B. Baker has demonstrated that the fluctuation of the ground-water level in the State of Michigan is similarly fol- lowed by a change in the morbidity and mortality from typhoid fever.^ Over thirty years ago Dr. Henry I. Bowditch, of Boston, called attention to the frequent connection between cases of pulmonary con- sumption and dampness of the soil upon which the patients lived. After a very extended and laborious investigation Dr. Bowditch for- mulated these two propositions : — ''First. — A residence in or near a damp soil, whether that damp- ness be inherent in the soil itself or caused by percolation from ad- jacent ponds, rivers, meadows, or springy soils, is one of the prin- cipal causes of consumption in Massachusetts, probably in New Eng- land, and possibly other portions of the globe. "Second. — Consumption can be checked in its career, and possi- bly — ^nay, probably — prevented in some instances by attention to this law."3 Dr. Buchanan, of England, about the same time showed that the thorough drainage of certain English cities had markedly dimin- ished the deaths from consumption in the drained cities. So far as the writer is aware, not a single fact has been established which militates against the law laid down by Dr. Bowditch, and so strongly supported by the statistical researches of Dr. Buchanan, yet hardly any notice has been taken of these results by physicians. Eew know anything of them, and still fewer seem to have made practical use of such knowledge in advising patients. As corroborative of the views of Dr. Bowditch, the rarity of consumption in high and dry moun- tainous districts or plateaus may be cited. A study of the topographical distribution of consumption in the State of Pennsylvania, by Dr. William Pepper, apparently confirms Dr. Bowditch's conclusions in nearly every particular. It is now -The Relation of the Depth of Water in Wells to the Causation of Typhoid Fever, Public Health, vol. x, p. 184-213. ^ Consumption in New England and Elsewhere, 2d ed., p. 87. Boston, 1866. DISEASES OF ANIMALS DUE TO CONDITIONS OF SOIL. 169 known that the direct cause of consumption is the bacilhis tuberculosis, discovered by Dr. Robert Koch. The relation between soil-moisture and the increase of consumption will probably be found in the more favorable conditions of development of the tubercle bacillus fur- nished by a moist medium. DISEASES OF ANIMALS PROBABLY DUE TO SIMILAR CONDITIONS OF THE SOIL. The modern study of the sanitary relations of the soil is still in its infancy. Whatever definite knowledge has been gained relates merely to physical or chemical conditions of the soil and its atmos- phere and moisture, or possibly the relations of these to the spread of certain diseases in human beings. But there is, perhaps, a wider application that may be made of such knowledge than has been here- tofore suggested. The domestic animals which form such a large por- tion of the wealth of this country — horses, cattle, sheep, and hogs — are liable to infectious and contagious diseases, as well as are human beings, and many millions of dollars are lost annually by the ravages of such diseases. Now, from what is known of such diseases as sple^iic fever among cattle, and of the so-cal'ed sivine-plague, it does not appear improbable to the writer that the source of infection is a soil polluted by the poisonous germ of these diseases. The laborious investigations of M. Pasteur in France have shown that the cause of splenic fever, when once introduced into a locality, will remain active for months, and even years, and it seems probable that a study of the soil in its relation to the diseases of domestic animals is a subject to which attention may profitably be given. It is well known that milch-cows frequently suffer from a disease identical in its nature with consumption in human beings. It is be- lieved by many that the milk of such animals is not only unfit for food by reason of its poor quality, but that it may convey the dis- ease to human beings when used as food. The observations of Bow- ditch and Buchanan, quoted above, show that consumption in man may be, and doubtless is, frequently favored by soil-wetness. It seems probable that the same cause should produce similar effects in the lower animals, and it is the writer's firm conviction that an exam- ination into the circumstances under which cows become attacked by consumption would prove this probability a fact. 170 TEXT-BOOK OF HYGIENE. DRAINAGE In many soils drainage is necessary in order to secure a constant level of the ground-water at a sufficient depth below the surface. Drainage and sewerage must not be confounded with each other. Drainage contemplates only the removal of the ground-water, or the reduction of its level, while sewerage aims to remove the refuse from dwellings and manufactories, including excrementitious matters, waste-water, and other products, and in some cases the storm-water. Sewers should never be used as drains, although for economy's sake sewer- and drainage- pipes may be laid in the same trench. Sewer-pipe must be perfectly air-tight and water-tight to prevent escape of its liquid or gaseous contents into the surrounding soil and rendering it impure. Drainage-pipe, on the other hand, should be porous and admit water freely from without. Escape of the contents of the drain-pipe into the surrounding soil will not produce any pol- lution of the latter. The best material for drains is porous earthenware pipe, or the ordinary agricultural drain-tile. Coarse gravel or broken stones may also be used, and prove efficient if the drains are properly constructed. Eeferring again to the aphorism of Professor De Chaumont, that a persistently low ground-water, say 5 metres down, or more, is healthy ; that a persistently high ground-water, less than l^/o metres from the surface, is imhealthy, and that a fluctuating level, especially if the changes are sudden and violent, is very unhealthy, the necessity ap- pears obvious, that in the construction of drainage- works the drains should be placed at a sufficient depth to secure a level of the ground- water consistent with health. This depth should never be less than 3 metres, and, if possible, not less than 5 metres. Care must be taken that the outflow of the drain is unobstructed, in order that the soil may be kept properly dry at all times. In the absence of a proper mechanical system of drainage, the planting of certain trees may efficiently drain the soil. It has been found that the eucalyptus tree has produced drying of the soil when planted in sufficient numbers in marshy land. The roots absorb a prodigious quantity of water, which is then given off by evapora- tion from the leaves. Sunflower-plants have a similar effect upon wet soils. It is for this reason that the planting of eucalyptus trees is recommended in malarial regions. QUESTIONS TO CHAPTER IV. THE SOIL. Why is it necessary to possess a knowledge of the physical and chemical conditions of the soil? What substances are included in the consideration of soils? Of what is the surface soil composed? How do soils vary in composi- tion, physically and chemically? What occupies the interstices of the soil? Upon what does the propor- tion of air in the soil depend? Is this proportion comparatively great or small? What relation has the soil-air to the atmosphere air, and what causes the difference in composition? In what way does the soil-air differ from the atmospheric air? Has the soil-air any definite composition? What are the factors governing the variation in composition? What kind of a soil will be likely to contain most carbon dioxide and least oxygen? What does this indi- cate? What micro-organisms are always to be found in the soil-air? What pathogenic organisms may also make the soil and soil-air their habitat? How may these be carried from place to place? To what are movements of the ground-air due? How may this soil-air gain access to our houses, and what measures should be taken to prevent its entrance? When is the danger greatest? Why are certain infectious diseases less prevalent in spring and early summer than in autumn? Why is there greater danger of infection from these diseases at night than in the day-time? Is the carbon dioxide of the soil-air a measure of the impurity of the soil? What causes the excess of carbon dioxide? When is the proportion of carbon dioxide greatest? Why are living-apartments below the surface of the ground very apt to be un- healthy? What is meant by the term "ground-water"? Where is it to be found? Has it a definite current? In what direction is the flow? Upon what does the level of the ground-water depend? What class of the population derive their drinking-water largely from the ground-water? ^^Tiat are som.e of the sources of contamination of the ground-water? What are some of the deduc- tions to be made accordingly? In what part of the soil do the processes of organic decay and putrefac- tion occur most readily? What are the causes of these processes? What are some of their products? What is the distinction between non-putrefactive decomposition or decay and putrefaction? How may disease be spread by the rise and fall of the ground- water ? WTiat two infective diseases are especially apt to be transmitted in this way? Give instances that tend to prove this. Upon what other disease has a damp soil a directly causative influence? What diseases of animals are likely to be influenced in a similar manner? How deep below the surface should the soil- water persistently be that the soil may be healthy? Wliat effect upon health has a suddenly and markedly fluctuating soil-water? Is a soil with its water persistently near the surface apt to be healthy? What do we mean by drainage, and what are its object and function? What is the difference between it and sewerage? How should drains be laid? What is the best material for drains? What precautions must be observed in the laying of drains? How may the surplus water be taken from the soil otherwise than by drains? (171) CHAPTER V. REMOVAL OF SEWAGE. In all larger communities certain arrangements are necessary to secure a prompt and efficient removal of excreta and the refuse and used water of households and manufacturing establishments, the sweepings of streets, and rain-water. The total quantity of excrementitious products — feces and urine — for each individual, including men, women, and children, has been estimated by Professor von Pettenkofer as 90 grammes of fecal and 1170 grammes of urinary discharge daily. This would give for a population of 1000 persons 34,000 kilogrammes of feces and 428,000 litres of urine per year. If to this is added a minimum allowance of 159 litres of water per day to each individual, a complete sewerage system for a population of 1000 persons would require provision for the discharge of 160,000 litres of sewage passing through the sewers every day. In this estimate storm-water and such accessory feeders of the sewers are omitted. The organic matters contained in sewage, even if free from the specific germs of disease, give rise to noxious emanations, which, when inhaled, probably produce a gradual depravement of nutrition that renders the system an easier prey to disease. For this and other reasons it is imjDortant that such measures be adopted as will secure the removal of sewage matters from the immediate vicinity of houses as quickly as possible after they have been discharged. The impregnation of the soil with sewage produces a contamina- tion of ground-air and ground-water, which may become a source of grave danger to health. By polluting the ground-water it eventually vitiates the well-water, which is nearly always derived from that source. The system of removal of excrementitious matters which any community will adopt depends to a considerable extent upon financial considerations. Although the sanitarian must insist upon the pre-emi- nent importance of the cause of public health, his suggestions will re- ceive little attention from municipal or State legislatures unless they can be carried out without involving the community too deeply in debt. For this reason it is a matter of great practical importance that the (173) REMOVAL OF SEWAGE. 173 student of sanitary science should make liimself familiar with the relative cost as well as with the hygienic significance of the various methods of sewage removal in use. The different systems in use for the removal of sewage matters may be considered in detail under the following five heads: — 1. The common privy, or privy-vault system. 2. The Eochdale or pail system, and its modifications. 3. The earth- or ash- closet system. 4. The pneumatic system of Liernur. 5. The water-carriage systems. 1. The Privy and Privy-well Systems. — While from a sanitary point of view privies of all kinds, whether wells or cess-pits, are to be unreservedly condemned, it is not likely that they will cease to be built for many years to come. It becomes necessary, therefore, to point out by what means the objections against them may be dimin- ished, and their evil consequences in some measure averted. In the first place, a privy-vault should be perfectly water-tight, in order to prevent pollution of the surrounding soil by transudation of the contained excremental matters. The walls should be of hard- burned brick laid in cement. The cavity should be small in order that the contents may be frequently removed, and not allowed to remain and putrefy for months or years. A water-tight hogshead sunk in the ground makes an economical privy-tank or receiver. A privy must not be dug in a cellar, or in too close proximity to the house-walls. Unless these last precautions are taken the offensive gases from the mass of decomposing fecal matter in the privy will constantly ascend into and permeate the air of the house. All privies should be ventilated by a pipe passing from just under the privy-seat to a height of about a metre above the roof of the house. A gas-flame, kept burning in the upper portion of this pipe, will increase its ventilating power by creating a strong and constant upward current. Deodorization of the contents of privies may be secured in a measure by means of sulphate of iron, phenyle, carbolic acid, chloride of lime, or dry earth. The first named is probably the most econom- ical, most easily applied, and very effective. A solution containing from ^/2 to 1 kilogramme of the salt in 4 litres of water is poured into the privy as often as necessary to prevent offensive odors. This solution may be conveniently prepared by suspending a basket or bag containing about 25 kilogrammes of the sulphate in a barrel of 174 TEXT-BOOK OF HYGIENE. water. In this way a saturated solution will be maintained until the salt has been entirely dissolved. Phenyle is likewise a good deodor- izer as well as an excellent disinfectant. The most rigid deodorization by chemicals will, however, be less effective than thorough ventilation, for it must be remembered that the mere destruction of an offensive odor is not equivalent to remov- ing all the deleterious properties that may be present. It is not at all certain that those elements of sewage which are the most offensive to the sense of smell are most detrimental to health. Privies should be emptied of their contents at stated intervals. A strict supervision should be exercised over them by the municipal authorities in cities and towns to prevent overflowing of their con- tents. In many places the method of removing the contents of privies is the primitive one with shovel, or dipper and bucket. In most cities and large towns, however, the privy-vaults or tanks are now emptied by means of one of the so-called odorless excavating machines, of which there are a number of patents. The process is rarely entirely odorless, however, as the carelessness of the workmen fre- quently permits offensive gases to escape and pollute the air for a considerable distance. All the different forms of the apparatus act upon the pneumatic principle. One end of a large tube is carried into the cess-pool or vault to be emptied and the other attached to a pump, by means of which the material is pumped into a strong bar- rel-tank carried on wheels. At the top of the tank is a vent, over which is placed a small charcoal furnace to consume the foul gases escaping from the vent. In some cities and many of the smaller towns and villages in this country the primitive midden or pit system is still in use. A shallow pit is dug in the ground, over which is erected the privy. When the pit is full another is dug close by the side of it, and the earth from the new pit thrown upon the excrement in the old one. The privy is then moved over the new pit, and this is used until it too becomes full. The proceeding is repeated as often as the pit be- comes filled up with the excreta, until in the course of a few years all the available space in a yard has been honey-combed with the pits. Then the custom adopted in overcrowded cemeteries is followed, namely, the first pit is dug out again and the cycle is repeated. In other cities the privy-well system is largely in use. This is — next to the midden or shallow pit just described — ^the most pernicious system for the disposal of excreta that can be imagined. The wells REMOVAL OF SEWAGE. 175 are dug to such a depth as to reach the subterranean flow of water, in which the soluble excremental matters are constantly carried off. Hence these receptacles rarely fill up or need cleaning. Eor this reason they are popular with property owners ; for, next to the primi- tive midden, they are the most economical of all the various methods adopted. The utter perniciousness of the system is, however, plain, because the soil for a considerable distance around each of these wells becomes a mass of putrid filth, contaminating the ground-water which feeds the drinking-water supplies in the vicinity; po. luting also the ground-air, which eventually reaches the surface, or the interior of houses, when the pressure of the outside atmosphere diminishes or the ground-water level rises. It must, therefore, be evident that the best ventilating arrangements, or the most thorough and consistent disinfection, can have very little, if any, effect in removing the very grave objections to this baneful system. The privy-well system for the removal of excreta cannot be recom- 'mended for adoption by any sanitarian. 2. The Rochdale, or Pail-closet System. — The Eochdale system of removal of excreta has won the support of many distinguished sanitarians on account of its simplicity, its economy, and its com- pliance with most sanitary requirements. The excreta, both solid and liquid, are received into a water-tight pail, either of wood or metal, and removed once or oftener a week, a clean and disinfected pail being substituted for the one removed. In Eochdale, Manchester, and Glasgow in Great Britain, in Heidelberg in Germany, and in other cities abroad, where this system has been introduced, it has worked satisfactorily. In this country a modification of the pail system, known as the Eagle Sanitary Closet, has been in- troduced by a firm in Charleston, S. C. The receptacle consists of an enameled-iron reservoir, with a neck just large enough to fit under the seat of the privy, and a quantity of disinfectant solution is put into the receptacle to prevent putrefaction of the excreta. The re- ceptacles are replaced by clean ones every week. Mr. James T. Gardner, Director of the New York State Sanitary Survey, says, in a special report on methods of sewerage applicable in small towns and villages, concerning the pail system^ : — "Eochdale is a city of some 70,000, and Manchester of between 400,000 and 500,000 inhabitants. The higher class of houses are al- lowed to have water-closets, but four-fifths of the people are obliged ^ Second Annual Report of New York State Board of Health, pp. 322, and 323. 176 TEXT-BOOK OF HYGIENE. to have 'pail-closets' in their yards built according to plans of the Health Department. Their essential features are : A flag-stone floor, raised a few inches above the level of the yard ; a hinged seat, with a metal rim underneath for directing urine into the pail, which stands on the flag directly beneath the seat; a hinged front and back to the seat, so that the pail or tub may be easily taken out and the place cleaned; and a 6-inch ventilating pipe from under the seat to above the roof. In Eochdale they use a wooden pail or tub made of half of a disused paraffine cask, holding about 40 kilogranuiies ; in Man- chester the 'pail' is of galvanized iron and holds 40 litres. Under the direction of the authorities, they are removed once a week in covered vans, which bring clean tubs to be put in the place of the full ones taken away. Each tub is covered with a close-fitting double lid before removal. The tubs are taken to a depot, where their contents are deodorized and prepared as manure by mixing with ashes and a small proportion of gypsum to fix the ammonia. Subsequently, street- sweepings and the refuse of slaughter-houses are added. At Man- chester there is by the side of each closet a very simple ash-sifter, from which the ashes fall into the tub and help to deodorize its con- tents. "The manure at Eochdale sells for about four-fifths of the cost of the collection and preparation. "In 1873 the net cost to the town of removing and disposing of the house dry refuse and excrement was only about $95 per annum per 1000 of population — less than 10 cents a person per annum. "The system has been in operation more than twelve years. "The tubs are removed in the daytime without offensive odor. "Where ashes are frequently thrown into the tubs at Manchester, very little odor is to be perceived in the closets. "For the villages of the State, which can have no general water- supply, I would unhesitatingly advise the use of the 'pail' or tub system as practiced in Manchester, England, as being, from a sanitary point of view, an immense improvement over the death-breeding privy- vaults in common use. The cheapness of the plan and the smallness of the original outlay of brains and money, in comparison with that needed to build a good sewer system, will make it possible to introduce a tub-privy system into most villages half a century before sewers would meet with any consideration. "At a small cost the existing privy-vaults can be cleaned and filled, and the privies altered into healthful tub-closets. The town authorities must then arrange for the removal of the tubs once a REMOVAL OF SEWAGE. 177 week, and for their thorough cleansing and disinfecting. Any iso- lated house, or group of houses, can use the tub system, taking care of it themselves. If the jDlan is adopted in villages it will doubtless spread into the country, and become the most powerful means of abolishing the fatal privy-vaults which are poisoning the farm-wells." 3. Earth- and Ash- Closets. — The earth- and ash- closets are devices in use to a large extent in England, and to a less degree in this country, for the purpose of rendering human excreta inodorous by covering them immediately after they are voided with dry earth 115^."^-. -"f Fig. 11. Fig. 11. — Pull-up Handle Commode, Showing the Door Open for Removing Pail. The flap of the seat and earth reservoir are also partially raised to show the construction. Fig. 12. — Showing the Apparatus Mounted on Bearers as when Fixed. Seat removed, showing mechanical arrangement. or ashes. The earth-closet is the invention of the Eev. Henry Moule, of England, and consists of an ordinary commode or closet, the essential feature of which is a reservoir containing dried earth or ashes, a quantity of which, amounting to about twice the quantity of feces voided, is thrown upon the evacuation either by hand or by means of an automatic apparatus called a "chucker." Just as in the ordinary water-closet, by raising a handle a supply of water is thrown into a hopper to wash down the feces into the soil-pipe, so, in the usual form of tlie earth-closet, raising the handle projects a quan- 178 TEXT-BOOK OF HYGIENE. tity of earth upon the evacuated feces and urine. By this means the excreta are rendered entirely inodorous and dry. The contents of the closets may be collected into a heap in a dry place. In the course of a few months the organic constituents have become oxi- dized, and the earth may be used over again for a number of times. A well-known sanitarian states that he has used sifted anthracite coal-ashes ten or twelve times over in the course of three years. During this time the material under no circumstances gave any indi- REMOVAL OF SEWAGE. I79 cation that it was "anything but ashes, with a slight admixture of garden-soil."^ Dr. Buchanan, of England, comparing the advantages of the earth-closet with those of the water-closet, says : "It is cheaper in original cost; it requires less repairs; it is not injured by frost; it is not damaged by improper substances being thrown down it; and it very greatly reduces the quantity of water required by each house- hold."^ In cities and towns the removal of the excreta should be carried out by or under the immediate direction of the municipal sani- tary authorities. If this is neglected, abuses are liable to creep in which will vitiate the performance of any system, however faultless when properly managed. Many advocates of the pail, dry earth, or privy systems urge the advantage of the large quantity of valuable manure which can be realized by converting the excremental matters into poudrette and other fertilizing compounds. Experience has shown, however, that the cost of preparing a satisfactory fertilizer from human excrement is much greater than can be realized from its sale. In all places in Great Britain and the continent of Europe where it has been tried the decision is against its practicability. The agricultural consider- ation should, however, be a secondary one, if the systems mentioned are economical and meet the sanitary requirements (which the privy system certainly does not). The adoption of one or other of them may be secured where more perfect but more complicated and ex- pensive systems may be out of the question. 4. The Pneumatic System of Liernur. — A system which seems to be useful in larger cities, especially where the topographical condi- tions are such as to render necessary mechanical aid in overcoming ob- stacles to natural drainage, is the pneumatic system devised by Captain Liernur, of Holland, and generally known as the Liernur system. It consists of a set of soil-pipes running from the water-closets to cen- tral district reservoirs, from which the air is exhausted at stated intervals. When a vacuum is created in the reservoir the contents of the water-closets and soil-pipes are driven forcibly into the reservoir by the pressure of air. The district reservoirs are connected by a separate system of pipes with a main depot, and the transfer of the fecal matter from the former to the latter is also accomplished with ''■ Thfi Sanitary Drainage of Houses and Towns, Waring, p. 250. 2d ed., 1881. * Quoted in Waring, above cited, p. 264. 180 TEXT-BOOK OF HYGIENE. the aid of pneumatic pressure. The complete system of Liernur provides that at the main depot the fecal matter shall be treated with chemicals, evaporated, and converted into a dry fertilizer — poudrette. It appears from the published reports that while the system has been partially adopted in three Dutch cities, in only one of them, Dor- trecht, has the machinery for manufacturing poudrette been estab- lished. With reference to this Erismann* says : "It seems never to have been in regular working order, for the fecal masses are mixed with street-sweepings and ashes into a compost-mass which causes no little discomfort in the neighborhood by the offensive odors. In Amsterdam the fecal matters, which frequently do not find a ready sale, are partly made into a compost with sweepings, partly used to fertilize meadows, or simply discharged into the water." As to the practical working of the system the opinions differ widely. While the majority of sanitarians, including Virchow, von Pettenkofer, and Mr. Eawlinson, objected to it as not fulfilling the demands of hygiene, the system has also been criticized by engineers as not being in accordance with the well-known principles of their science.^ Two other plans for the removal of fecal matter by pneumatic pressure have been invented, namely, the Shone and the Berlier sys- tems. Neither of these has been adopted to any considerable extent. Both seem to the author to fall far short even of the merits of the Liernur system. 5. The "Water-carriage System of Sewerage. — Two systems of removal of sewage by water-carriage are in use at the present time. They are technically known as the "combined" and the "separate" systems. In the former, which is the system upon which the most of the sewers in this country are constructed, all excreta, kitchen- slops, waste-water from baths and manufacturing establishments, as well as storm-water, are carried off in the same conduits. In the separate system, on the other hand, the removal of the storm-water is provided for, either by surface or underground drains, not con- nected with the sewers proper, in which only the discharge from water-closets and the refuse-water from houses and factories are conveyed. In the separate system the pipes are of such small calibre *Von Pettenkofer und Ziemssen: Handbuch der Hygiene. II Th., II Abth., 1 Hefte, p. 140. ^Papers by Maj. C. H. Latrobe and Col. Geo. E. "Waring, Jr., in Fifth Biennial Report Md. State Board of Health. See also, in favor of system, a paper by Dr. C. W. Chancellor, in same publication, and an elaborate descrip- tion by the same author in Trans. Med. and Chir. Facidty of Md., 1883. KEMOVAL OF SEWAGE. 181 that a constant flow of their contents is maintained, preventing deposition of suspended matters and diminishing decomposition and the formation of sewer-gas. In the combined system, on the other hand, the sewers must be made large enough to receive the maximum rain-fall of the district. This requires a calibre greatly in excess of the ordinary needs of the sewer, and furnishes favorable conditions for the formation of sewer- gas and the development of minute vegetable organisms. The ordi- nary flow in a sewer of large calibre is usually so sluggish as to promote the deposition of solid matters and the gradual obstruction of the sewer. It is the opinion of the most advanced sanitarians that the sepa- rate system fulfills the demands of a rational system of sewerage better than any other at present in use. The separate system of sewage, indorsed as it is by high engi- neering and sanitary authorities, and by a satisfactory, practical test in the city of Memphis and in the town of Keene, IST. H., seems to the author to possess merits above any other plan for the removal of excreta and house-wastes. The following description is from a paper by Colonel George E. Waring, Jr. : "A perfect system of sanitary sewerage would be something like the following: ISTo sewer should be used of a smaller diameter than 6 inches (15 centimetres) : a, be- cause it will not be safe to adopt a smaller size than 4-inch (10 centi- metres) for house-drains, and the sewer must be large enough to remove whatever may be delivered by these ; &, because a smaller pipe than^ 6-inch would be less readily ventilated than is desirable; c, and because it is not necessary to adopt a smaller radius than 3 inches (5 centimetres) to secure a cleansing of the channel by reasonably copious flushing. "No sewer should be more than 6 inches (15 centimetres) in diameter, until it and its branches have accumulated a sufficient flow at the hour of greatest use to fill this size to half full, because the use of a larger size would be wasteful, and because when a sufficient ventilating capacity is secured, as it is in the use of a 6-inch pipe, the ventilation becomes less complete as the size increases, leaving a larger volume of contained air to be moved by the friction of the current, or by extraneous influences, or to be acted upon by changes of temperature and volume of flow within the sewer. "The size should be increased gradually, and only so rapidly as is made necessary by the filling of the sewer half full at the hour of greatest flow. 182 TEXT-BOOK OF HYGIENE. "Every point of the sewer should, by the use of gaskets or other- wise, be protected against the intrusion of cement, which, in spite of the greatest care, creates a roughness tliat is liable to accumulate obstructions. "The upper end of each branch sewer should be provided with a Field's flush-tank of sufficient ca^Dacity to secure the thorough daily cleansing of so much of the conduit as from its limited flow is liable to deposit solid matters by the way. "There should be sufficient man-holes, covered by open gratings, to admit air for ventilation. If the directions already given are ad- hered to, man-holes will not be necessary for cleansing. The use of the flush-tank will be a safegiiard against deposit. With the system of ventilation about to be described, it will suffice to place the man- holes at intervals of not less than 1000 feet (305 metres). "For the complete ventilation of the sewers it should be made compulsory for every householder to make his connection without a trap, and to continue his soil-pipe above the roof of the house. That is, every house connection should furnish an uninterrupted ventilation-channel 4 inches (10 centimetres) in diameter through- out its entire length. This is directly the reverse of the system of connection that should be adopted in the case of storm-water and street-wash sewers. These are foul, and the volume of their contained air is too great to be thoroughly ventilated by such appliances. Their atmosphere contains too much of the impure gases to make it pru- dent to discharge it through house-drains and soil-pipes. With the system now described, the flushing would be so constant and com- plete and the amount of ventilation furnished, as compared to vol- ume of air to be changed, would l)e so great, that what is popularly known as 'sewer-gas' would never exist in any part of the public drains. Even the gases produced in the traps and pipes of the house itself would be amply rectified, diluted, and removed by the con- stant movement of air through the latter. "All house connections with the sewers should be through in- lets entering in the direction of the flow, and these inlets should be funnel-shaped so that their flow may be delivered at the bottom of the sewer, and so that they may withdraw the air from its crown; that is, the vertical diameter of the inlet at its point of junction should be the same as the diameter of the sewer. "All changes of direction should be on gradual curves, and, as a matter of course, the fall from the head of each branch to the out- REMOVAL OF SEWAGE, 183 let should be continuous. Eeduction of grade within this limit, if considerable, should always be gradual. "So far as circumstances will allow, the drains should be brought together, and they should finally discharge through one or a few main outlets. "The outlet, if water-locked, should have ample means for the admission of fresh air. If open, the mouth should be protected against the direct action of the wind. "It will be seen that the system of sewerage here described is radically different from the usual practice. It is cleaner, is much more completely ventilated, and is more exactly suited to the work to be performed. It obviates the filthy accumulation of street-manure in catch-basins and sewers, and it discharges all that is delivered to it at the point of ultimate outlet outside the to^^vn before decom- position can even begin. If the discharge is of domestic sewage only, its solid matter will be consumed by fishes if it is delivered into a water-course, and its dissolved material will be taken up by aquatic vegetation. "The limited quantity and the uniform volume of the sewage, together with the absence of dilution by rain-fall, will make its dis- posal by agricultural or chemical processes easy and reliable. "The cost of construction, as compared with that of the most restricted storm-water sewers, will be so small as to bring the im- provement within the reach of the smaller communities. "In other words, while the system is the best for large cities, it is the only one that can be afforded in the case of small towns. "Circumstances are occasionally such as to require extensive en- gineering works for the removal of storm-water through very deep channels. Ordinarily, the removal of storm-water is a very simple matter, if we will accept the fact that it is best carried, so far as possible, by surface gutters, or, in certain cases, by special con- duits, placed near the surface. "It is often necessary, in addition to the removal of house-waste, to provide for the drainage of the subsoil. This should not be ef- fected by open joints in the sewers; because the same opening that admits soil-water may, in dry seasons and porous soils, permit the escape of sewage matters into the ground, which is always objec- tionable. "Soil-water drains may be laid in the same trench with the sewers, but preferably, unless they have an indepenrlent outlet, on a shelf at a higher level. When they discharge into the sewer they 184 TEXT-BOOK OF HYGIENE. should always deliver into its upper part, or into a man-hole at a point above the flow-line of the sewage.'"^ The establishment of a system of sewerage presupposes a con- stant and abundant supply of water to keep all closets clean and all house-drains and street-sewers well flushed. Where this cannot be obtained, sewers would be likely to prove greater evils than benefits. In such cases one of the methods of removal of excreta before men- tioned, either the pail- or earth- closet system, should be adopted. The final disposal of sewage is a problem that depends for its solution partly upon the agricultural needs of the country around the city to be sewered, partly upon the proximity of large bodies of water or running streams. When the city is situated upon or near large and swiftly-flowing streams, the sewage may be emptied di- rectly into the stream without seriously impairing the purity of the latter, although the principle of thus disposing of sewage is wrong. Dilution, deposition, and oxidation will soon remove all appreciable traces of the sewage of even the largest cities. Where, on the other hand, the stream is inadequate in size to carry off the sewage, or where, as in the Seine and Thames, the current is sluggish, some other method of final disposal must be adopted. In many cities of Great Britain and the continent of Europe the disposal of the sewage by irrigation of cultivated land has been prac- ticed for a number of years. The reports upon the working of the system are generally favorable, although some sanitarians express doubts of the efficiency of the system. In using sewage for the irriga- tion of land, two objects are secured: first, the fertilization of the land by the manurial constituents of the sewage, and second, the purification of the liquid portion by filtration through the soil. The organic matters which have been held back by the soil undergo rapid oxidation in the presence of air and the bacteria of decay, and are converted into plant-food, or into harmless compounds. Sewage irri- gation, as practiced in Europe, must make provision for the disposal of a very large proportion of water in the sewage (street-wash, storm- water), which requires much larger areas of land than would be needed if only sewage material proper (water-closet and kitchen-waste) was thus to be disposed of. Eecent experiments have shown that the purification of sewage is a biological process depending on the action of bacteria. ' The Sewering and Drainage of Cities, Waring, Public Health, vol. v, p. 35. REMOVAL OF SEWAGE. 185 The more important bacteria found in sewage are'^ : — OBLIGATORY AXAEEOBES. Spirillum 7'ugula. — Gives rise to fecal odor. Spirillum amyliferum. — Acts as a vigorous ferment. Bacillus hiityricus. — Gives rise to much gas. FACULTATIVE ANAEROBES, OR AEROBES. Bacillus putrificus coli. — Decomposes albuminous substances, with liberation of ammonia. Bacillus mycoides. proteus vulgaris. — Produces ammonia from nitrogenous matter and denitrification. Bacillus fluorescens putridus. — Produces trimethylamine. Micrococcus urece. — Converts urea into ammonium carbonate. Bacillus lactis a'ero genes. — Produces carbon dioxide and hydrogen. Bacillus coli communis. — Produces gas, chiefly hydrogen. Bacillus suhtilis. — Eapidly consumes oxygen. Proteus sulphureus. — Produces hydrogen sulphide and mercaptan. Bacillus sulpJiureum. — Liquefies gelatin and casein and produces hydrogen sulphide. In addition, several other species of bacteria are present in sew- age, the action of which is not definitely loiown. Of disease-producing bacteria, bacillus cholerse, bacillus dysenterise (Shiga), bacillus ty- phosus, streptococci, and staphylococci have been found. These bacteria produce certain changes in the organic matter, resolving the highly complex organic molecules into simple inorganic compounds. The changes taking place in sewage are as follows (Eideal) : — Table XXVII. Initial Transient aerobic changes by the oxygen of the water supply rapidly passing to : FiEST Stage Anerobic liquefaction and preparation by hydroly- Substances dealt with Urea, Ammonia, and easily decomposable matters. Albuminous matters . Cel- lulose and fibre fats. Characteristic Products Soluble nitrogenous com- pounds. Phenol deriva- tives. Gases. Ammo- nia. ^ Sewage and the Bacterial Purification of Sewage. S. Rideal, 1901. 186 TEXT-BOOK OF HYGIENE. Table XXVII. — ( Continued). Second Stage Semi-anerobic breaking down of the intermedi- ate dissolved bodies. Thied Stage Complete aeration : nitri- fication. Substances dealt with Amido compounds. Fatty acids. Dissolved resi- dues. Phenolic bodies. Ammonia and carbona- ceous residues. Characteristic Products Ammonia. Nitrites. Gases. Carbon dioxide, water, and nitrates. Based on these principles, various methods of purification of sewage have been adopted. 1. Broad Irrigation. — This method is defined by the Eoyal Com- mission on Metropolitan Sewage Discharge as "the distribution of sewage over a large surface of ordinary agricultural land, having in view a maximum growth of vegetation (consistent with due purifi- cation) for the amount of sewage supplied." 2. Irrigation with Copious TJnderdrainage. — This method is de- fined as "the concentration of sewage, at short intervals, on an area of specially-chosen porous ground, as small as will absorb and cleanse it ; not excluding vegetation, but making the produce of secondary im- portance." 3. Sedimentation or Chemical Precipitation, Followed by Broad Irrigation or Filtration. — In this system the sewage is precipitated by lime or iron sulphate, the precipitate allowed to settle, and the supernatent liquid is distributed over large areas of land or made to pass through sand filters. The latter method is employed successfully in Worcester, Mass. However, the difficulty of disposing of the sedi- ment, or "sludge," is quite serious and greatly impairs the utility of the system. 4. Sterilization by Heat and Disinfection. — These methods, while no doubt the most efficient, are not practical on a large scale. 5. Bacterial Purification. — This system, otherwise known as the "septic tank" method, is the outcome of a series of experiments made since 1865, which proved that the disintegration and final purifica- tion of sewage are due to the action of micro-organisms. In 1865, Dr. A. Mueller wrote: "The contents of sewage are chiefly of organic origin, and in consequence of this an active process of decomposition takes place in sewage, through which the organic matters are gradu- ally dissolved into mineral matters, or, in short, are mineralized, and REMOVAL OF SEWAGE. 187 thus become fit to serve as food for plants. To the superficial observer this process appears to be a chemical self-reduction; in reality, how- ever, it is chiefly a process of digestion, in which the various — mostly microscopically small — animal and vegetable organisms utilize the organically fixed power for their life purposes." The "septic tank" is merely a large cesspool in which the sew- age undergoes putrefactive changes brought about by the activity of anaerobic bacteria. "The septic or bacterial tank may be built of concrete, brick, masonry, or wood, and it may be covered or not, though a light cov- ering of boards, to prevent the wind and rain breaking up the sur- face scum, may be advisable. An airtight covering is necessary only when the tank is located in a portion of the community where its odors would become a nuisance. The tanks should be large enough to hold the sewage of 2000 persons for one day, or about 55,000 gallons. In the most approved tanks there arq two compartments, the first being about ten feet deep by seven feet long and eighteen feet wide and known as the ^grit chamber,' as it is designed to receive the grit and heavier settlings from the sewage. Into this the crude sewage is led by two inlet pipes, which discharge about five feet beneath the surface, so as not to disturb either the surface crust or the settled sediment. From this first chamber the contents flow through sub- merged openings in the partition wall into the second compartment, which is about seven feet deep, sixty-five feet long, and of the same width as the first. The flow is maintained at a rate to take twenty- four hours from entrance to exit. The effluent is brownish yellow in color and more or less offensive in odor. "In the septic tank, as in the cesspool, the anaerobic or putre- factive bacteria are the active agents, and so energetic are they on a warm day that the contents of the tank seem fairly to boil, though, of course, the temperature is but slightly above that of the surrounding air. The microbes penetrate the solids floating in the sewage, and their gaseous products accumulate in such volume as to carry the solids to the surface of the tankage, sometimes with sufficient force to project them through the overlying crust. It is this and the escap- ing gas which give the boiling appearance on a hot day. The whole mass is very actively at Vork,' and the process is identical with that which takes place in a jar of forking' apple-butter or pre- serves insufficiently cooked or insufficiently supplied with cane sugar. In short, the process is one of fermentation, and by it 40 to 60 per cent, of the organic matter is removed, while over the bottom of the 188 TEXT-BOOK OF HYGIENE. tank accumulates the small percentage of ^ash' or mineral matter originally combined in the sewage, amounting to a deposit of some- thing over a foot per year. The gas generated is rich in hydrocarbons and may be used for fuel or illumination." From the "septic tank" the sewage, which is now completely hydrolyzed, is passed through beds of either broken brick, cinders, coke, or stone, the so-called "contact beds," or sand, to which the term "filter-bed" is applied. While passing through these beds, the re- maining organic impurities are oxidized by the aerobic bacteria. The rate of filtration is about 500,000 gallons per acre per day. The resulting effluent is clear, colorless, practically odorless, and practically free from sewage bacteria. Such an effluent may be safely emptied into a stream without danger of polluting it. The "septic tank" treatment of sewage has been also employed for the purification of the sewage on a small scale. The following adaptation is recommended bv the Illinois State Board of Health® : — "This plant consists of two tanks, the first the septic tank proper ; the second, a discharging tank. The septic tank is, in construction, practically a cistern 4 feet in diameter and about 3 feet deep. The sewage from the house enters this tank through a lightly trapped pipe, the flow from the ordinary household preventing the back-flow of air. Across the center of the tank is a wall, which divides it into two chambers of equal size. The height of this wall is exactly to the point of outflow. "The sewage from the house enters the first chamber of the septic tank with considerable force, causing some disturbance of the con- tents. The flow over the dividing wall into the second chamber, how- ever, is even and slow, so that the contents of the second chamber are not disturl)ed, and the flocculent matter settles readily to the bottom. "The bacterial action on the contents of this tank is often so complete that there is no appreciable residue or sludge, and in this case the tank will rarely if ever have to be cleaned out. In some instances, however, the tank will require occasional cleaning. The sludge from a well-constructed tank is not offensive, and may be dis- posed of without difficulty. "The sewage is carried into the discharging chamber (which is a cistern 6 feet in diameter and about 4 feet in depth), through a deeply trapped pipe. The second or discharging tank should be of sufficient size to hold the overflow from the septic tank for a period « Bull. No. 2, 1906. REMOVAL OF SEWAGE. 189 of 12 to 24 hours. At the bottom of the discharging tank is an automatic siphon, which is opened automatically when the efliuent reaches a certain height in the tank or chamber — a height of about 2^/2 feet. Through this siphon the contents of the chamber will pass 'in a very few moments, at which time the siphon will automatically close and the chamber will again refill. "From the siphon, a pipe conducts the effluent to the place of discharge, usually on a lawn, or in a pasture or field. "The effluent is usually entirely without odor and is inoffensive in every way. It may be discharged upon a lawn, provided the lawn is well under-tiled and drained, or it may be emptied into any stream, provided the water from the stream is not used for drinking purposes. While it is true that raw sewage is frequently directed into streams whose water is used for domestic purposes, it is contrary to the policy of the State Board of Health to sanction even the discharge of this comparatively harmless effluent into such streams." A number of small septic tank disposal plants have been con- structed in the vicinity of Wilmington, Del., for the disposal of the sewage from large residences. The results have proved quite satis- factory. Garbag^e. — By garbage is meant refuse from the kitchen. This should be collected in air-tight receptacles and frequently removed for final disposal. The latter may be effected either by feeding the garbage to hogs or cremation. While cremation is the more expen- sive of the two processes, it is also the more sanitary and should be preferred on that account. QUESTIONS TO CHAPTER V. REMOVAL OF SEWAGE. Why must arrangements be made in all large communities for the re- moval of sewage? To what do the organic constituents of sewage give rise, and Avhat is the effect upon health of the continued inhalation of these prod- ucts? How else may the impregnation of the soil with sewage endanger health? What, then, is the object of any system of sewage removal? What will likely govern the choice and adoption of a sewage-removal system by any community ? What different systems are in use at the present time? Which of these is the worst and most unsanitary? In case the privy system is to be con- sidered, what conditions should be insisted upon? How may a pri\'y be ven- tilated? Why should a privy not be located in a cellar nor too near the house? What substances may be used to deodorize the contents of privy-vaults, and how? Are deodorizers always disinfectants, and is the danger necessarily removed when the odor is destroyed? How often should privy-vaults be emptied? How may this be done without offense to the senses? What are the grave objections to the midden or shallow-pit system, and to digging the vault or cess-pool to the level of the ground-water? What is meant by the Rochdale or pail-closet system? What are some of its advantages? What can be said of its efficacy for large communities and for the economy of administration? What is an earth-closet, and upon what does its efficacy depend? What are some of its advantages? Describe the pneumatic system of Liernur. Has it apparently been satis- factory in its workings? What other systems have employed the pneumatic principle, and with what success? What do we mean by the water-carriage system of sewerage? What two systems are embraced under this head? Wliat is the distinction between the two? Which is in most common use? What must be the size of the sewers in the combined system, and what are the consequent objections? Why does the separate system seem the better? Describe the latter in detail. What governs the size of the drains in the separate system? How is this system kept clean and free from obstruction? How is it to be ventilated? How does it differ in this respect from the combined system? 'S^Hiat are some of the especial points to be observed in the construction? What may be said as to cost of construction and as to the ultimate disposal of the sewage? Why should sewers not be employed to drain the subsoil? How may this be done? What does the establishment of a sewerage system presuppose? If plenty of water cannot be had, what system of sewage removal should be adopted ? (190) QUESTIONS TO CHAPTER V. 191 In what way maj' we finally dispose of the sewage? What are the objec- tions to discharging it into running streams? How will it be finally disposed of in such a stream ? What is meant by the irrigation, the sub-irrigation, and the filtration methods? What becomes of the organic matter of the sewage in each case? What of the sewage water? What sort of soil is needed for the irrigation method? What can be said of the disposal of sewage and garbage by cremation? What chemicals are used for the precipitation of sewage? What action have bacteria on sewage? What is the septic tank method of purification of sewage? How may this method be used on a small scale? How should garbage be disposed of? CHAPTER VI. CONSTRUCTION OF HABITATIONS. The importance of observing the principles of hygiene in the construction of habitations for human beings is not sufficiently appre- ciated by the pub'ic. Architects and builders themselves have not kept pace with the sanitarian in the study of the conditions necessary to be observed in building a dwelling-house which shall answer the requirements of sanitary science. In an investigation conducted by Dr. Yillerme^ it was found that in France, from 1821 to 1827, of the inhabitants of arrondissements containing 7 per cent, of badly-constructed dwellings, 1 person out of every 72 died; of the inhabitants of arrondissements containing 22 per cent, of badly-constructed dwellings, 1 out of 65 died; while of the inhabitants of arrondissements containing 38 per cent, of badl3^-constructed dwellings, 1 out of every 45 died. Inseparable from the question of the defective construction of dwellings is that of overcrowding in cities, because the most crowded portions of a city are at the same time those in which the construction of dwellings is most defective from a hygienic standpoint. The fol- lowing tables show the relations of the death-rate to density of popu- lation in various large cities of Europe, and also the relations between overcrowding in dwellings and the mortality from contagious dis- eases : — Table XXVIII. RELATION OF DEATH-RATE TO DENSITY OE POPULATION. City Mean Number of Inhab- itants to each house Average Dea'h-rate per 1000 Inhabitants London 8 32 35 52 55 24 Berlin 25 Paris 28 St. Petersburg 41 Vienna 47 ^Quoted in Ilealencyelopaedia d. ges. Heilk., Bd. ii, 71. (192) CONSTRUCTION OF HABITATIONS. 193 In Glasgow, the death-rate in apartments with 1.31 occupants is 21.7 per 1000, while in apartments with 2.05 occupants the rate is 28.6 per 1000. In Buda-Pesth, in 1872-73, it was found that out of every 100 deaths from all causes there were, from contagious diseases : — 20 deaths in dwellings with 1 to 2 persons in each room. 29 " " " " 3 " 5 " " " 32 " " " " 6 " 10 " " " 79 " " " " over 10 " " " " Dr. Jose A. de los Eios gives the following statistics, bearing upon the mortality of cholera, in relation to the number of persons occupying one room when attacked by it : — Of 10,000 persons attacked by cholera, and living- 1 person to the room, 68 died. Of 10,000 persons attacked by cholera, from 1 to 2 to the room, 131 died. Of 10,000 persons attacked by cholera, living 2 to 4 to the room, 219 died. Of 10,000 persons attacked by cholera, living 4 or more to the room, 327 died. These figures show very clearly the vital importance of the appli- cation of sanitary laws in the construction and occupation of dwell- ings. The direct relation of overcrowding to pulmonary tuberculosis has been firmly established by recent statistics, ISTot only do the absence of light, air, and sunshine usually found in overcrowded tene- ments favor the long life of the tubercle bacillus, but the aggregation of people, many of whom are tuberculous, tends to a rapid dissemi- nation of the disease. The tuberculosis problem will never be satis- factorily solved so long as the housing of the poor will remain in the wretched condition in which we see it to-day in large cities. Another curious and suggestive point is presented by some statis- tical researches on the mortality of Berlin, in regard to the death- rate among persons living in different stories of houses. It was found, for example, that the mortality in fourth-story dwellings is higher than in the lower stories. Even basement dwellings furnish a lower death-rate. Still-births, especially, occur in a larger propor- tion among the occupants of the upper stories of houses. This may be explained by the unfavorable effects of frequent stair-climbing, especially on pregnant women. 194 TEXT-BOOK OF HYGIENE. It is in the death-rate among young children that the effects of overcrowding and unsanitary construction of dwellings are especially manifest. The mortality returns from all the large cities of the world give mournful evidences of this every summer. The researches of Dr. H. I. Bowditch upon soil-wetness, to which reference has already been made in a previous chapter, show conclu- sively that persons living in houses situated upon or near land habit- ually or excessively wet, are especially prone to be attacked by pul- monary consumption. Dr. Buchanan- has corroborated the truth of Dr. Bowditch's observations by ehowing, from the records of a num- ber of cities and towns of Great Britain, that, with the introduction of a good drainage system, bringing about a depression and uniformity of level of the ground-water, the mortality from consumption and other diseases very markedly diminished. The following table, show- ing the proportionate amount of this diminution, is abridged from the official reports^ : — Table XXIX. RESULTS OF SANITARY W^ORK. Name of Place. a a ll P. <2 Average Mor- tality per lOOO bnfore Con- struction of Works Average Mor- tality per 1000 since Comple- tion of Works «2 o g Reduction of Typhoid Fever Rate (per cent.) 10,238 23.4 20.5 12.1 48 33,954 33 2 22.6 32 40 30,229 23 7 18.6 22 63 23,108 22 6 20.9 7 36 7,847 23.9 20.5 14 56 68,056 26 4 25.2 41- 48 27,475 29.8 23.7 20 48 52,778 33.2 26.2 18 60 24,756 31.8 21.6 32 36 7,818 19.1 18.6 2} 10 9,030 27.5 21.9 20 75 10,570 22.7 21.0 n 52 Banbnry . . Cardiff .... Croydon . , . Dover Ely Leicester . . . Macclesfield Merthyr . . . Newport . . Rugby Salisbury . . Warwick . . 41 17 17 20 47 32 31 11 32 43 49 19 The following must be taken into account in building a house in accordance with sanitary principles: — I. SITE. The building-site should be protected against violent winds, although a free circulation of air all around the house must be se- ' Ninth and Tenth Reports of the medical officer to the Privy Council. ' Sanitary Engineering, Baldwin Latham, p. 2. Chicago, 1877. CHARACTER OF THE SOIL. 195 cured. Close proximity to cemeteries, marshes, and injurious manu- facturing establishments or industries must be avoided if possible. A requisite of the highest importance is the ability to command an abundant supply of pure water for drinking and other purposes. A neglect of this precaution will be sure to result to the serious incon- venience, if not detriment, of the occupants of the house. II. CHARACTER OF THE SOIL. The soil should be porous and free from decomposing animal or vegetable remains, or excreta of man or animals. It should be freely permeable to air and water, and the highest level of the ground-water should never approach nearer than 3 metres to the surface. The fluc- tuations of the ground-water level should be limited. In this connection, attention is again called to the aphorism of Dr. De- Chaumont.* It is impossible to say positively that any kind of soil is either healthy or unhealthy, merely from a knowledge of its geological char- acters. The accidental modifying conditions above referred to, viz., organic impurities, moisture, the level and fluctuations of the ground- water, are of much greater importance than mere geological formation. The late Dr. Parkes, however, regarded the geological structure and conformation as of no little importance, and summarized the sani- tary relations of soils, variously constituted, as follows^ : — "1. The Granitic, Metamorphic, and Trap Rocks. — Sites on these formations are usually healthy; the slope is great, water runs off readily; the air is comparatively dry; vegetation is not excessive; marshes and malaria are comparatively infrequent; and few im- purities pass into the drinking-water. "When these rocks have been weathered and disintegrated they are supposed to be unhealthy. Such soil is absorbent of water; and the disintegrated granite of Hong Kong is said to be rapidly per- meated by a fungus; but evidence as to the effect of disintegrated granite or trap is really wanting. "In Brazil the syenite becomes rapidly coated with a dark sub- stance and looks like plumbago, and the Indians believe this gives rise to "^calentura' or fevers. The dark granitoid, or metamorphic trap, or hornblendic rocks in Mysore are also said to cause periodic fevers; and iron hornblende, especially, was confirmed by Dr. Heyne, of * Chapter iv, p. 130. '" Practical nvgicnc fith ed., vol. i, p. 359. 196 TEXT-BOOK OF HYGIENE. Madras, to be dangerous in this respect. But the observations of Eichter on similar rocks in Saxony, and the fact that stations on the lower spurs of the Himalayas on such rocks are quite healthy, negative He}Tie's opinion. " 2. The Clay Slate. — These rocks precisely resemble the granite and granitoid formations in their effects on health. They have usu- ally much slope, are very impermeable, vegetation is scanty, and nothing is added to air or drinking-water. "They are consequently healthy. Water, however, is often scarce, and as to the granite districts, there are swollen brooks during rain, and dry water-courses at other times, swelling rapidly after rains. " 3. The Limestone and Magnesium Limestone Rocks. — These so far resemble the former that there is a good deal of slope and rapid passing off of water. Marshes, however, are more common, and may exist at great heights. In that case, the marsh is probably fed with water from some of the large cavities which in the course of ages become hollowed out in the limestone rocks by the carbonic acid in the rain, and form reservoirs of water. "The drinking-water is hard, sparkling, and clear. Of the various kinds of limestone, the hard oolite is best and magnesium is worst; and it is desirable not to put stations on magnesium limestone if it can be avoided. " 4. The Chalk. — The chalk, when mixed with clay, and perme- able, forms a very healthy soil. The air is pure, and the water, though charged with calcium carbonate, is clear, sparkling, and pleasant. Goitre is not near'y so common, nor apparently calculus, as in the limestone districts. "If the chalk be marly, it becomes impermeable, and is then often damp and cold. The lower parts of the chalk, which are underlaid by gault clay, and which also receive the drainage of the parts above, are often very malarious; and in America some of the most marshy districts are in the chalk. "5. The Sandstones. — The permeable sandstones are very healthy ; both soil and air are dry; the drinking-water is, however, sometimes impure. If the sand be mixed with much clay, or if clay underlies a shallow sand-rock, the site is sometimes damp. • "The hard millstone-grit formations are very healthy, and their conditions resemble those of granite. " 6. Gravels of any depth are always healthy, except when they are much below the general surface, and water rises through them. Gravel hillocks are the healthiest of all sites, and the water, which CHARACTER OF THE SOIL. 197 often flows out in springs near the base, being held up by the under- lying clay, is very pure. " 7. Sands. — There are both healthy and unhealthy sands. The healthy are the pure sands, which contain no organic matter, and are of considerable depth. The air is pure, and so is often the drinking- water. Sometimes the drinking-water contains enough iron to be- come hard, and even chalybeate. The unhealthy sands are those which, like the subsoil of the Landes, in southwest France, are com- posed of silicious particles (and some iron) he'd together by a vege- table sediment. "In other cases sand is unhealthy from underlying clay or laterite near the surface, or from being so placed that water rises through its permeable soil from higher levels. Water may then be found within 3 or 4 feet of the surface; and in this case the sand is imhealthy and often malarious. Impurities are retained in it and effluvia traverse it. "In a third class of cases the sands are unhealthy because they contain soluble mineral matter. Many sands (as, for example, in the Punjab) contain magnesium carbonate and lime-salts, as well as salts of the alkalies. The drinking-water may thus contain large quantities of sodium chloride, sodium carbonate, and even lime and magnesian salts and iron. Without examination of the water it is impossible to detect these points. "8. Clay, Dense Marls, and Alluvial Soils Generally. — These are always regarded with suspicion. Water neither runs off nor runs through; the air is moist; marshes are common; the composition of the water varies, biit it is often impure with lime and soda salts. In alluvial soils there are often alterations of thin strata of sand, and sandy, impermeable clay. Much vegetable matter is often mixed with this, and air and water are both impure. "The deltas of great rivers present these alluvial characters in the highest degree, and should not be chosen for sites. If they must be taken, only the most thorough drainage can make them healthy. It is astonishing, however, what good can be effected by the drain- age of even a small area, quite insufficient to affect the general atmos- phere of the place; this shows that it is the local dampness and the effluvia which are the most hurtful. "9. Cultivated Soils. — Well-cultivated soils are often healthy; nor at present has it been proved that tlie use of manure is hurtful. Irrigated lands, and especially rice-fields, which not only give a great surface for evaporation, but also send up organic matter into the air. 198 TEXT-BOOK OF HYGIENE. are hurtful. In Northern Italy, where there is a very perfect sys- tem of irrigation, the rice-grounds are ordered to be kept 14 kilo- metres (8.7 miles) from the chief cities, 9 kilometres (5.6 miles) from the lesser cities and the forts, and 1 kilometre (1094 yards) from the smaller towns. In the rice countries of India [and America] this point should not be overlooked.'' Where a wet, impermeable, or impure soil must, of necessity, be chosen as a building-site, it should be thoroughly drained. The minimum depth at which drains are laid should be not less than ly, metres below the floor of the cellar or basement. Such a soil should be covered with a thick, impervious layer of asphaltum or similar cement under the house, in order to prevent the aspiration of the pol- luted ground-air into the building. It is a frequent custom in cities to fill in irregularities of the building-site with street-sweepings and garbage, which always con- tain large quantities of decomposing organic matters. This is a gross violation of the plainest principles of hygiene. It is almost equally reprehensil)le to use such decaying or putrefying organic mate- rial for the purpose of grading streets or sidewalks in cities and to-uTis." It should be the constant endeavor of all sanitary authorities to prevent pollution of the soil as much as possible in villages, towns, and cities. Where houses are built on the declivity of a hill, the upper Avail should not be built directly against the ground, as it would tend to keep the wall damp. A vacant space should be left between the wall and the ground to permit free access of air and light. In addition to, or in default of, drainage, the dryness of soil can be promoted by rapidly-growing plants, which absorb water from the soil and give it out to the air. The sunflower and the eucalyptus tree are the most available for this purpose. III. THE MATERIAL OF WHICH THE HOUSE IS BUILT. The nature of the most appropriate building material depends upon so many collateral circumstances that definite rules cannot be * During the very fatal epidemic of yellow fever in New Orleans, in 1878, it was ascertained that a contractor for street-work used the garbage and street-scrapings to grade the bed of the streets. Even though in this case it may not have intensified the epidemic in these localities, the practice is so contrary to the simplest sanitary laws that it should nowhere be tolerated. The author is aware, however, that the "made-ground" of nearlj' every city in this country is composed largely of just such material. All sanitarians should protest against a continuance of this pernicious practice. MATERIAL OF WHICH THE HOUSE IS BUILT. 199 laid down. As a general rule, moderately hard burned brick is the most serviceable and available material. It is easily permeable by the air, and so permits natural ventilation through the walls, unless this is prevented by other means. It does not absorb and hold water readily ; hence, damp walls are infrequent if brick is used. It is probably, of all building material, the most durable. On account of its porosity a brick wall is a poor conductor of heat. It therefore prevents the rapid cooling of a room in cold weather, and likewise retards the heating of the inside air from without in summer. Another very great advantage is its resistance to a very high degree of heat, brick being probably more nearly fire-proof than any other building mate- rial. In hot climates light wooden buildings are advantageous because they cool off very rapidly after the sun has disappeared. On account of the numerous Joints and fissures in a frame building, natural ven- tilation goes on very readily and to a considerable extent. Next to brick, granite, marble, and sandstone are the most ser- viceable building materials. Very porous sandstone is, however, not very durable in cold climates, as the stone absorbs large quantities of water, which, in consequence of the expansion accompanying the act of freezing, produces a gradual but progressive disintegration. Ee- cently, concrete has been successfully employed as a building material. The application of paint to the walls, either within or without, almost completely checks the transpiration of air through the walls, thus limiting natural ventilation. Calcimining, on the other hand, offers very little obstruction to the passage of air. Wall-paper is about midway between paint and lime-coating in its obstructive effect on atmospheric transpiration. ISTewly-built houses should not be occupied until the walls have become dry. Moisture in the walls is probably a not infrequent source of ill health; it offers favorable conditions for the development of fungi (possibly disease-germs), and by filling up the pores of the material of which the walls are composed, prevents the free transpira- tion of air through them. Moisture of the walls is sometimes due to the ascent of the water from the soil by capillary attraction. This can be prevented by inter- posing an impervious layer of slate in the foundation-wall. Where the moisture is due to the rain beating against the out- side walls, and thus saturating them if composed of porous materials. a thorough external coating of impervious paint will prove a good remedy. 200 TEXT-BOOK OF HYGIENE. IV. INTERIOR ARRANGEMENTS. A. Size of Eooms, and Ventilating and Heating Arrangements. — The rooms in dwelling-houses should never be under V- / ^ metres in height from floor to ceiling. In sleeping-rooms the initial air-space should never be less than 35 cubic metres for adults, and 25 cubic metres for children under 10 years of age. Provision must be made for changing this air sufficiently often to maintain it at its standard of purity; i.e., less than 7 parts of carbon dioxide per 10,000. The details for accomplishing this will vary with the architect's designs, the material of which the house is constructed, the climate, and the season. The principles laid down in the section on ventilation (Chapter 1) should be adhered to. In cold weather the air should be warmed, either before its entrance into the room or afterward, by stove or fire-place. Gallon's jacketed stove, or fire-place, seems to answer this purpose admirably. The details of the heating apparatus must be left to individual taste, or other circumstances. It may be noted, however, in passing, that the prevailing method of heating houses by means of hot air is objectionable for various reasons: partly, because the air is usually too dry to be comfortable to the respiratory organs; partly, because organic matter is frequently pres- ent in large proportions, and gives the air an offensive odor when the degree of heat is high enough to scorch the organic matter. Both these objections are, however, removable; the first by keeping a vessel of water constantly in the furnace, so that the hot air can take up a suffi- cient proportion of vapor in passing tlirough, and, the second, by having the furnace made large enough so that the temperature need never be raised to a very high degree. Heating by hot water or steam is preferable to the hot-air furnace. Both of these methods are, however, more expensive to install. Where special ventilating arrangements are necessary, air-inlets may be inserted at appropriate points in the walls of the room, fac- ing toward the air. A simple arrangement is that known as the Bury Ventilator, shown in Figs. 14 and 15. It consists of a wooden block interposed 'between the bottom of the lower window-sash and the window-frame. The air passes into the room through the open- ings in the block, as shown in the illustration. The separation of the upper and lower sashes, when the ventilator is in place, also adds to the efficiency of the ventilation, as the air passes in through the space so formed. INTEEIOR ARRANGEMENTS. 201 A cheaper ventilator can be made by simply tacking a strip of canvas, binders' board, or manilla jiaper, 20 to 25 centimetres wide, across the lower portion of the window-frame, and then raising the Fie. 14. Fis;. 15. Fig. 14. — a, a, Sash. 6, &, Window-jambs, c, c, Window-sill. This cut represents the view from within the Bury Ventilator, in operation. It is broken away at one end to show the sash raised above the outer holes to admit the air. Fig. 15. — a, a, Sash. This cut represents the view from without the Bury Ventilator, in operation. The sasJi is broken away to show the ventilator behind, with the fresh air passing in. sash 10 to 15 centimetres. The air will pass in under the lower and between the lower and upper sashes and pass upward toward the ceil- ing find thou grndnany difl'upe itself through the room. In summer 202 TEXT-BOOK OF HYGIENE. a counter-opening may be obtained for the escape of foul air by low- ering the upper sash, while in winter a stove or fire-place will furnish a good exit. p^ O O be Fig. 16 shows the probable course of the air-currents in a room ventilated by means of a fresh-air inlet near the ceiling and an open fire-place. A is the inlet ; C, the fire-place ; G, the floor ; F, ceiling ; E E, flues. INTERIOR ARRANGEMENTS. 203 B. Internal Wall-coating. — A point of considerable importance in the outfitting of dwelling-liouses is the material used for coating or decorating the inside of the walls. Green paint ar.d green-colored wall-papers should be rejected. The reason for avoiding this color is the following: Bright-green pigments and dyes are largely com- posed of some compound of arsenic, which becomes detached from the wall or paper when dry and, being inhaled, produces a train of symptoms which have been recognized as chronic arsenical poisoning. Many cases have been reported in which serious and even fatal poison- ing has been produced in this way.'^ It would be advisable, therefore, to discard all bright-green tints in paints and ornamental paper- hangings. C. Lighting. — Provision should be made in all dwelling-houses for an abundant supply of sunlight. Every room should have at least one window opening directly to the sun. It is not sufficient to give an ample window-space, which should be in the proportion of one to five or six of floor-space, but the immediate surroundings of the house must be taken into account. Thus, close proximity of other buildings, or of trees, may prevent sufficient light entering a room, although the window-space may be in excess of that required under ordinary circumstances. Some form of artificial light will also be needed in all dwell- ings. Certain dangers are necessary accompaniments of all avail- able methods of artificial illumination. The danger from fire is, of course, the most serious. This danger is probably least where candles are used, and greatest where the more volatile oils (kerosene, gasolene) are employed. The use of candles results in pollution of the air by carbon dioxide and other products of combustion to a greater degree than when other illuminating agents are used; they also give out a larger amount of heat in proportion to their power of illumina- tion. Kerosene gives a good light when burned in a proper lamp, and is cheap, but the dangers from explosion and fire are consider- able. The danger from explosion can be greatly reduced by always keeping the lamp filled nearly to the top, and never filling it near a light or fire. The danger of explosion is Increased when the chimney of the lamp is broken, as then the temperature of the metal collar, by which the burner is fastened to the lamp, is rapidly raised® and the oil vaporized. If, at the same time, the lamp is only partially 'Arsenic in Certain Green Colors, F. W. Draper. Third Annual Report Mass. State Board of Health, 1872, pp. 18-57. »H. B. Baker, in Report Mich. State Board of Health, 1876, p. 48. 204 TEXT-BOOK OF HYGIENE. filled with oil, the space above it is occupied by an explosive mixture of air and the vapor of the oil. If this is heated to a sufficient degree an explosion will take place. ^ The use of coal-gas is probably attended by less danger than the lighter oils, but by more than other means of illumination. In addi- tion to the dangers from fire and explosions, which are inevitable ac- companiments of defects in the fixtures, the escaping gas is itself exceedingly poisonous from the large amount of carbon monoxide it contains. It is, in fact, a very frequent occurrence in large cities that persons are killed by the inhalation of gas which has escaped from the fixtures or was allowed to escape from the burner through igno- rance. That variety of illuminating gas Imown as "water-gas" is more dangerous to inhale than coal-gas owing to the larger proportion of carbon monoxide contained in it. Eecent experiments by T. A. Maass indicate that the toxic action of illuminating gas is due in part to some factor aside from the carbonic oxide, as it is so much more toxic than CO alone. The "natural gas" used as a fuel and illuminant in some places in the United States is especially dangerous from the total absence of odor. The gas may escape in large quantity and fail to give notice of its presence except by an explosion, if ignited, or by producing asphyxia in those who incautiously venture into the air permeated by it. The slight but continuous escape of gas from defective or leaky fixtures may produce a grave form of anemia. Chronic CO poisoning is probably of more frequent occurrence in cities than is generally suspected. The electric light (Edison's incandescent system) is probably open to less objection on the score of danger than any other of the illuminating systems mentioned. There is no trustworthy evidence that the electric light has any unfavorable influence on the vision, although Eegnault supposed it would have a bad effect upon the ocular humors on account of the large proportion of the violet and ultra-violet rays it contained. In order to remove this objection Bouchardat advised the wearing of yellow glasses by those compelled to use this light for close work. The advantages of the incandescent light, besides the brilliant white light it gives, are that it is steady and does not produce any heat, nor does it pollute the air with car- bon dioxide and other products of combustion. Professor von Petten- kofer has shown experimentally that the pollution of the air by 'the products of combustion is very much greater when gas is used "See an instructive paper by Prof. E.. C. Kedzie, in Report Mich. State Board of Health for 1877, p. 71 et seq. HOUSE-DRAINAGE. 205 than where the electric light is employed. The electric arc-lights are extremely dangerous on account of the high potential maintained in the wires, and the difficulty of thoroughly insulating the latter. Many deaths have occurred from this source, and unless a method is dis- covered and adopted by which the voltage of the arc-light current can be greatly diminished without decreasing the efficiency of the light, this method of lighting must soon be given up in cities, owing to its danger, not only to those directly brought in contact with the conduc- tors, but to others who may indirectly get in the way of the errant current. In writing, sewing, reading, or other work requiring a constant use of accurate vision, the light, whether natural or artificial, should fall upon the object from above and on the left side. Hence, windows and burners should be at least the height of the shoulder and to the left of the person using the light. Increased ventilation facilities must be provided where artificial light (except the electric light) is used to any extent. It has been •calculated that for every lighted gas-burner 12 to 15 cubic metres of fresh air per hour must be furnished in addition to the amount or- dinarily required in order to maintain the air of the room at the standard of purity. V. WATER=SUPPLY. The water-supply of a dwelling-house should be plentiful for all requirements, and its distribution should be so arranged that the supply for every room is easily accessible. Where practicable, water- taps should be placed on every floor, both for convenience and for greater safety in case of fire. It is also a result of observation that personal habits of cleanliness increase in a direct ratio with the ease of obtaining the cleansing agent. The inmates of a house where water is obtainable with little exertion are much more likely to be cleanly in habits than where the water-supply is deficient or not readily procured. VI. HOUSE=DRAINAGE. Provision must be made for the rapid and thorough removal of waste-water and excrementitious substances from the house. This is most easily and completely accomplished by well-constructed water- closets and sinks. Water-closets should, however, not be tolerated in any room occupied as a living- or bed- room. It would doubtless be 206 TEXT-BOOK OF HYGIENE. very much more in accordance with sanitary requirements to have all permanent water-fixtures, water-closets, and bathing arrangements placed in an annex to the dwelling proper. In this way the most serious danger from water-closets and all arrangements having a connection with a cess-pool or common sewer — permeation of the house by sewer-air — could be avoided. Water-closets, hovrever, presuppose an abundant supply of water. Unless this can be obtained and rendered available for flushing the closets, soil-pipe, and house-drain, the dry-earth or pail system should be adopted. Privies should not be countenanced. Experience in sev- eral large cities of Europe has demonstrated^*' that the pail system can be adopted with advantage and satisfactorily managed even in large communities. As house-drainage may be considered the first and most import- ant link in a good sewerage system, a brief description will be here given of the details of the drainage arrangements of a dwelling- house. The rapid and complete removal of all fecal and urinary discharges, lavatory- and bath- wastes, and kitchen-slops must be provided for. For these purposes are needed, first, water-closets and urinals, wash-basins and bath-tubs, and kitchen- or slop- sinks; second, a perpendicular pipe, with which the foregoing are connected, termed the soil-pipe; and tliird, a horizontal pipe, or house-drain, connecting with the common cess-pool or sewer. A. Water-closets. — There are five classes of water-closets in gen- eral use. They are the pan-, valve-, plunger-, hopper-, and washout- closets. Pan-closets are those found in most old houses containing water- closet fixtures. Just under the bowl of the closet is a shallow pan con- taining a little water, in which the dejections are received. On rais- ing the handle of the closet, the pan is tilted and the water at the same time is turned on, which washes out the excrement and sends it into or through the trap between the closet and the soil-pipe. It will be readily understood that the space required for the movement of the pan — the "container," as it is termed — is rarely thoroughly cleansed by the passage of water through it. Fecal matter, paper, etc., gradually accumulate in the comers of the container, and, as a con- sequence, pan-closets are always, after a brief period of use, foul. There are other defects in the construction of the pan-closet which render it untrustworthy, but the one especially pointed out — the See Chapter v, p. 139. HOUSE-DRAINAGE. 207 impossibility of keeping it clean — :s enough to absolutely condemn its use, from a sanitary point of view. It is decidedly the worst form of closet that can be used. Valve-closets are merely modifications of the pan-closet. The bottom of the bowl is closed by a flat valve, which is held in its place by a weight. By moving a lever the valve is turned down, allowing the excreta to drop into the container. The only differences between the pan- and valve-closets are that in the latter a flat valve is substi- tuted for the pan of the former, and that this allows the container Fig. 17. — The "Dececo" Closet (New Form) to be made smaller. Otherwise there are no advantages in the valve- closet. Considered from a sanitary standpoint, the valve-closet is no worse than the pan-closet, and but very little, if any, better. The third variety, or plunger-closet, has several marked advan- tages over the two just described. -The characteristic feature of the closets of this class is that the outlet, which is generally on one side of the bowl, is closed by a plunger. This bowl is always from one- third to one-half full of water, into which the excreta fall. On rais- ing the plunger, the entire contents of the bowl are rapidly swept out of the apparatus into the soil-pipe, the bowl thoroughly washed out 208 TEXT-BOOK OF HYGIENE. Fiff. 18.— The "A. G. M." Closet. HOUSE-DRAINAGE. 209 by a sudden discharge of water, and, on closing the outlet with the plunger, the bowl is again partly filled with water. An overflow attachment prevents accumulation of too large a quantity of water in the bowl. This overflow, however, sometimes becomes very foul and objectionable. The Jennings, Demarest, and Hygeia are types of this class. The principal objection is that the plunger sometimes fails to properly close the outlet, allowing the water to drain out of the bowl, and thus destroying one of its principal advantages. The me- chanism is also somewhat complicated and likely to get out of order. Fig. 19.— Sectional View of "A. G. M." Closet. The hopper-closet consists of a deep earthenware or enameled iron bowl, with a water seal trap directly underneath. The excreta are received directly inio the proximal end of the trap, and when the water is turned on the sides of the bowl are washed clean and everything in the bowl and trap swept directly into the soil-pipe. There is no complicated mechanism to get out of order, the trap is always in sight, and the entire apparatus can always be kept clean and inoffensive, as there are no hidden corners or angles for filth to lodge. This form of closet is, all things considered, one of the best for general use. 14 210 TEXT-BOOK OF HYGIENE. The "wash-out" closets are of various shapes, some having the trap in the bowl itself, others having a double water-trap. They are generally simple in construction, and not likely to get out of order. They do not present any decided advantages over the simple hopper, although at the present time they are more used than any other form of closet. Of the recent improvements in this form of closet may be mentioned the "A. G. M.,"" shown in view with intern in Fig. 18, and in section in Fig. 19, and the "Dececo," Fig. 17, invented by Col. George E. Waring, In the latter the automatic siphon principle, so ingeniously used by Eogers Field in the construction of the automatic flush-tank, is applied to the scouring of a water-closet. Practical experience for a number of years has demonstrated the great useful- ness of this closet. If the delivery of water from the flushing-cistern is properly regulated, at first rapid to thoroughly wash out the closet and connections, and then slow to re-establish the proper depth of seal in the trap, the closet should be thoroughly satisfactory in its workings. Water-closets should not be inclosed in wooden casings, as is al- most universally done. Everything connected with the closet, soil-, and drain- pipes, water-supply, and all joints and fixtures should be exposed to view so that the defects can be immediately seen and easily corrected. By laying the floor and back of the closet in tiles or cement, such an arrangement can even be made ornamental, as suggested by Waring,^" who says that a closet "made of white earthenware, and standing as a white vase in a floor of white tiles,' the back and side walls being similarly tiled, there being no mechanism of any kind under the seat, is not only most cleanly and attractive in appearance, but entirely open to inspection and ventilation. The seat for this closet is simply a well-finished hard-wood board, resting on cleats a little higher than the top of the vase, and hinged so that it may be conveniently turned up, exposing the closet for thorough cleansing, or for use as a urinal or slop-hopper." Where the arrangement here described is adopted, extra urinals are unnecessary and undesirable. Where they are used they should be constantly and freely flushed with water, otherwise they become very offensive. The floor of the urinal should be either of tiling, slate, or enameled iron. ^^Manufactured by the ilyers Sanitary Dapot, New York. " Sanitary Condition of New York City, Scribner's Monthly, vol. xxii, No. 2, June, 1881. HOUSE-DRAINAGE. 211 B. Water-supply for Closets. — The water-supply for flushing water-closets should not be taken directly from the common house- water supply, but each closet should have an independent cistern large enough to hold a sufficient quantity of water for a thorough flushing (30 to 30 litres) every time the closet is used. The objections to connecting the water-closet directly with the common house-supply are, that there is often too little head of water to properly flush the Tier. 20. — Flushinor Cistern for Water-closets. basin; and, secondly, if the water be drawn from a fixture in the lower part of the house, while the valve of a water-closet in an upper floor is open at the same time, the water will not flow in the latter (unless the supply-pipe is very large), but the foul air from the closet will enter the water-pipe, and may thus produce dangerous fouling of the drinking-water. Plence, separate cisterns for each water-closet should always be insisted upon. The arrangement of these cisterns is often difficult to compre- hend. Fig. 20 shows the interior arrangement of one form. The hall-shaped float, a, cuts off the s^ipply when the tank is full, while opening the valve, h, by means of the crank, c, discliargos the water. The rounded annex, d, contains water enough to partly fill the closet- 212 TEXT-BOOK OF HYGIENE. bowl and trap after the contents have been washed out by the rapid flush. C. Traps. — Every water-closet, urinal, wash-basin, bath-tub, and kitchen-sink should have an appropriate trap between the fixture and the soil-pipe. The trap should be placed as near the fixture as prac- ticable, as pointed out above; in the best forms of water-closet the bottom of the closet itself forms part of the trap. Traps differ in shape and mechanism. The simplest and usually efficient is the ordinary S-trap (Fig. 21). This trap is of uniform diameter throughout, and has no angles for the lodgment of filth. A free flush of water cleanses it perfectly, and it rarely fails to furnish a sufficient obstruction to the passage of sewer-air from the soil-pipe, unless the water has evaporated or been forced out under a back-pressure of air in the soil-pipe, or been siphoned out, and thus the seal broken. Fig. 21.— S-Trap. The D-trap and bottle-trap are objectionable on account of the great liability of becoming fouled by filth lodging in the corners, while in the mechanical traps, like Bowers' ball-valve trap, Cudell's trap, and others of this class, there is always danger of insufficient seal by filth adhering to the valve, and thus preventing its exact closure. Most of the traps now furnished by the dealers in plumber's supplies have an opening in the highest part for attaching a vent- pipe. It has been found that the seal in most traps can be broken by siphonage, if the pressure of air on the distal side (the side toward the soil-pipe) of the trap is diminished, or, on the other hand, by increase of pressure in the soil-pipe the water in the trap may be forced back into the fixture, and thus sewer-air enter the room. By providing for a free entrance and exit of air to the trap this break- ing of the seal can be prevented. The ventilation of traps is, however, an evil, as it furnishes an additional means of evaporation, and when HOUSE-DRAINAGE. 213 the fixture is not in frequent (daily) use the seal is sooner broken. The elaborate extra system of ventilation of traps, so generally insisted upon by plumbers and sanitary engineers, is unnecessary. If the soil- pipe is of the proper size and height, siphonage of traps will not be likely to occur. The waste-pipe connecting the fixture and the soil- pipe should be as short as possible; in other words, all water-closets, urinals, baths, and lavatories should be placed as near the soil-pipe as practicable, in order to have no long reaches of foul waste-pipe under floors or in rooms. Fig. 22. Fig. 23. Fig. 22. — Sectional View of Vent, with Cap in Normal Position. Fig. 23. — Sectional View of Vent, with Cup Lifted out of the Mercury by the Inflowing Current of Air Indicated by the Arrows. Dr. E. S. McClellan has recently invented a trap which obviates many of the objections urged against all previous devices, and is intended to meet the defects of the S and other traps. It consists of a body containing a light, inverted cup, with its edges resting in an annular groove containing mercury, which forms an absolute seal against the escape of sewer-air. When a slight diminution of pressure occurs on the sewer side of the cup, the greater external pressure lifts the cup out of the mercury and permits a free inflow of air until the wonted equilibrium is re-established, when the cup drops back into the mercury by gravity, and effectually closes the trap against any 214 TEXT-BOOK OF HYGIENE. outflow. With this trap siphonage of the seal is impossible. Fig. 22 shows this trap with the cup down, and Fig. 23 with the cup raised, allowing inflow of air. For an ordinary wash-bowl or bath-waste (which should always be trapped), the Connolly globe-trap, shown in Figs. 24 and 25, is an excellent fixture. It is impossible, under ordinary circumstances, to break the seal by siphonage. D. The Soil-pipe. — The vertical pipe connecting the water-closets and other fixtures with the house-drain is called the soil-pipe. It Fig. 24. — Connolly Globe-trap. Fig. 25. — Globe-trap Attached to Basin. should be of iron, securely jointed, of an equal diameter (usually 10 centimetres) throughout, and extend from the house-drain to from l^/o to 2 metres above the highest point of the house. The connec- tions of all the waste-pipes from water-closets, baths, etc., should be at an acute angle, in order that an inflow at or nearly at right angles may not produce an obstruction in the free passage of air up and down the soil-pipe. The diameter of the soil-pipe, at its free upper end, should not be narrowed ; in fact, according to Col. Geo. E. War- ing, the up draught is rendered more decided if the upper extremity HOUSE-DRAINAGE. 215 of the soil-pipe is widened.^^ The internal surface of the pipe should be smooth, and especial care should be taken to prevent projections inward at the joints; otherwise, paper and other matters will adhere to the projections, and gradually obstruct the pipe. E. The House-drain. — The horizontal or slightly inclined pipe which connects the lower end of the soil-pipe with the sewer or cess- pool, the point of final discharge from the house, should be of the same diameter and material as the soil-pipe. The joints should be made with equal care, and the pipe should be exposed to view throughout while within the house-walls. If sunk below the floor of the cellar it should be laid in a covered trench, so that it may be readily in- spected. The junction between the vertical and horizontal pipe should not be at a right angle, but the angle should be rounded. The drain-pipe should not be trapped. This is contrary to the advice of sanitary authorities generally, but the author thinks it unadvisable to trap the drain-pipe. There should be no obstruction to the out- flow of sewage from the house, and a trap in the drain-pipe is of no avail against the passage of sewer-air from the sewer or cess- pool into the soil-pipe, if the pressure of air in the former is increased. Furthermore, if the passage of air backward and forward between the sewer and the external air at a sufficient height (above the roofs of houses, for example) is free and unobstructed, the sewers (or the cess- pool, as the case may be) will be better ventilated than if any obstruc- tion to such free circulation, in the form of a trap, be placed in the drain-pipe. Nearly all sanitary authorities direct that an opening for the admission of fresh air — "fresh-air inlet" — should be made in the drain-pipe, before its connection with the sewer or cesspool. This is done with the view of having a constant current of fresh air enter- ing near the base of the soil-pipe and passing upward through it. Theoretically, the current ought always to pass in this direction. Practically, however, the current is found, at times, to pass the other way, and the foul air from the soil-pipe may be discharged into the air near the ground, where it would be much more likely to do harm than when discharged high up in the air beyond the possibility of being breathed. »»Am. Architect, p. 124, Sept. 15, 1883. 216 TEXT-BOOK OF HYGIENE. OFFICIAL SUPERVISION OF THE SANITARY ARRANGEMENTS OF DWELLINGS. In most towns and cities the municipal authorities have pro- vided for an official inspection of buildings, to prevent neglect of pre- cautions against fire and other manifest dangers to life. It is only very recently, however, that the authorities of some of the larger cities in this country have enacted laws to prevent improper construc- tion of house-drainage works. Although none of these laws or or- dinances cover the subject completely, yet their proper enforcement must result in great advantage. Within the past few years, following the example of Edinburgh, volunteer associations have been organized in various cities of this country, with the object of securing constant expert inspection and supervision of the drainage arrangements of dwellings and other necessary sanitary improvements. The good results accomplished by the Newport Sanitary Protec- tion Society, the ISTew Orleans Auxiliary Sanitary Association, and other similar bodies attest the usefulness of such organizations. THE INTERIOR ARRANGEMENT OF THE HOUSE. A dwelling is neither a store-house for furniture, a museum, nor a picture gallery. It is a place to live in with comfort and in accord- ance with hj'gienic rules. The interior furnishing, therefore, should be simple and neat. The furniture, and only so much of it as is needed for comfort, should be of such construction as not to gather dust. Upholstered furniture, with the exception of plain leather, is unsanitary and should not be tolerated. The floors should be polished and covered with rugs. The guiding principle in all cases should be a maximum of space and a minimum of dust. QUESTIONS TO CHAPTER VI. CONSTRUCTION OF HABITATIONS. Why should the principles of hygiene be observed in the construction of dwellings? What relation is there between badly-constructed and over- crowded dwellings in cities? Between overcrowded dwellings and the death- rate, either general or from contagious diseases? What class of persons are especially affected by overcrowding and unsanitary conditions of their dwell- ings? What points should be taken into consideration in building a house? What things are to be sought and what avoided in selecting a site ? On what kind of soil should the house be built? Hov/ far should the ground-water be below the surface, even at its highest? What must be known about a soil to determine whether it is sanitarily suitable for building purposes? What is the usual judgment concerning sites on granite, trap, or metamorphic rocks? What if they have been disintegrated? What regarding those on the clay slate? Limestone and magnesian limestone? Chalk? Sandstone? Gravel? Sands? Clays and alluvial soils? Cultivated lands? Which of the above is probably the best, on general principles, for the site for a dwelling? Where a site is wet or the soil is impure, what must be done? What is the mini- mum depth at which drains for the soil-water should be laid? How else may the drying of the soil be promoted? How should a cellar or basement over an impure soil be paved? What precaution should be observed in building a house against a hill? What are some of the materials of which the walls of a house may be built? What are the advantages of good brick? Why should very porous sandstone not be used for building purposes in cold climates ? What is the effect of paint upon houye-walls ? Has calcimining or white-washing the same effect? Has wall-paper? How soon should newly-built houses be occu- pied? To what are moist walls sometimes due, and how may they be obviated? What should be the minimum height of rooms in dwelling-houses? How much air-space should there always be in sleeping-rooms for adults and chil- dren? What is the standard of purity of the air that should be maintained constantly? What are the objections to heating by hot-air furnaces, and how may these objections be avoided? How may a room be ventilated without ex- pensive apparatus? What colors should be avoided in wall-paper and paints for inside work, and why? Wha.t should be the proportion of window-space to floor-space, and what other points should be observed in the day-lighting of rooms? What are the forms of artificial light used for household illumination, and what are the dangers accompanying each ? What are some of the especial advantages of the incandescent electric light? From what direction should the light (217) 218 QUESTIONS TO CHAPTER VI. come for ^yriting, reading, etc. ? Why must there be increased ventilation Avhere artificial lights (except incandescent electric) are used? How much fresh air per hour is needed to properly dilute the impurities produced by burning illuminating gas? What points are to be observed regarding the water-supply of a dwell- ing? Why should it be both abundant and convenient? How are waste-waters and excrementitious matters most readily re- moved from a house? Where would it be best to have all fixtures, etc., of a house-drainage system located, if possible? What do water-closets, etc., presuppose? If this cannot be had, what system should be adopted instead? For what must a proper house-drainage system provide? What are the component parts of such a system? Where should water-closets never be located? \^^iat five classes of water-closets are there? Which of these are most objectionable, and why? Describe briefly the construction of a pan- and a valve- closet. In what way is a plunger-closet better than a pan- or valve closet? Wherein is it sani- tarily imperfect? Why is the hopper-closet one of the best? What two kinds of hopper-closet are there? What can be said of the wash-out closets? What is the principle of siphon closets? Why should water-closets and other fixtures not be inclosed in wooden casings? How may the surroundings of such closets and fixtures be further improved? Why should the water-supply for closets not be taken directly from the house-supply? How much should the flushing cistern hold ? What are traps? Where should they be located? How many should there be in any system of house-drainage? What is the simplest form of trap? What are its advantages? I'pon what does the value of a trap depend? What is to be avoided in the selection of a ti'ap? What is meant by siphon- age? How can this be prevented? To what part of the trap is the vent-pipe to be attached? Where should the other 'end of the vent-pipe open? How else may the seal of a trap be broken ? What is the principle of McClellan's anti-siphon trap? How long should the waste-pipe connecting the fixtures with the soil- pipes be? What is the soil-pipe? Of what dimensions should it be? Where should its upper extremity end? What other precautions should be observed in regard to the soil-pipe? What is the house-drain? What care must be observed in the laying of it? What can you say regarding a trap between the house-drain and sewer? If a trap is thus located, what else must there be between the trap and the house, and why? What can be said regarding the official supervision of sani- tary arrangements in dwellings? What principle should underly the furnish- ing of a house? CHAPTER VII. CONSTRUCTION OF HOSPITALS. SITE. If the choice of a site for the habitations of healthy persons is a matter of vital importance, as was pointed out in the last chapter, it needs no argument to impress upon the reader the actual necessity of choosing a site with wholesome surroundings for a habitation for the sick. In selecting a site for a hospital, therefore, it is of prime importance to avoid a location where unsanitary influences prevail. While a hospital should always be easily accessible, it is not desirable that it should be in a noisy or crowded part of a city. Where a hospital is primarily designed for the reception of accident or "emergency" cases, it is, of course, necessary to have it near to where accidents are likely to occur. In a city this will probably be in the most crowded and noisy part. The direction of the prevailing winds from the city should be avoided in selecting a site for a hospital. Free admission of sunlight and air must be secured to all parts of the hospital. An elevated location is therefore desirable, although exposure to violent winds must, if possible, be avoided. The soil upon which a hospital is built should be c^ean, easily drained, with a deep ground-water level, not liable to sudden oscil- lations. The neighborhood of a marshy or known malarious region should be avoided. THE BUILDINGS. The building area must be large enough to permit the construc- tion of buildings in accordance with the modern recognized principles of hospital construction. Overcrowding is not permissible, either of the ground by buildings or of the buildings by patients. Hav'xig determined the number of patients for whom provision is to be made and the character of the diseases to be treated, an estimate must be made of the area necessary for a hospital. Taking into ac- count all the buildings needed, the area required will be— for two or more storied buildings — not less than 30 square metres per bed. (219) 220 TEXT-BOOK OF HYGIENE. If one-story buildings are to be erected more space will be required, and if infectious diseases are to be treated in the hospital the above space-allowance must be doubled or even trebled. In the Johns Hopkins Hospital, in Baltimore, the area occupied by the buildings is 56,000 square metres, and provision is to be made for 300 patients. This, covering, of course, the area occupied by the administration building, nurses' home, kitchen, dispensary, operating and autopsy theatre, laundry, etc., gives an area of 187 square metres per bed. The actual allowance of floor space per bed is IIV2 square metres; for patients with infectious diseases the space-allowance is nearly treble, being 29 square metres. Within recent years the principles of hospital construction h:ive undergone considerable modification. While formerly a large hospital consisted usually of one large, two or more storied building, in which all the various departments were comprised under one roof, the aim has recently been to scatter the wards as much as practicable, consistent with reasonable ease of supervision and administration. Under the former plan, with large wards connected by common corridors and stairways, ease of administration was primarily secured; in the lat- ter, the most important object of a hospital, "a, place for the sick to get well in," is more nearly attained. While many hospitals are still being constructed on the old plan, of a single block of several stories in height, nearly all sanitary authorities are agreed that the plan of separate pavilions of one or, at most, two stories, in which the build- ings are entirely disconnected, or connected only by means of an open corridor for convenience of administration, is best for the patients, and, leaving out of account the cost of the ground, is also the most economical. The recent development of the pavilion system of hospitals may be attributed largely to the success obtained in treating the sick and wounded in the simple barrack hospitals during the late war between the States. The army barrack hospital is the original type of the pavilion hospital of the present day. Each pavilion consists of one or two wards, containing from ten to thirty beds altogether. In each pavilion or ward is also a bath- and wash- room, water-closet, dining-room, scullery, attendants' room, and sometimes a day-room for patients able to be out of bed. The two-story pavilion is built on the same plan, and is generally adopted in cities, or where economy of space is desirable for financial reasons, and where no infectious diseases are treated. Where prac- ticable, one-story pavilions should always be adopted, as they are HOSPITAL BUILDINGS. 221 more easily heated, ventilated, and served than two-storied buildings. When a number of pavilions or wards are connected by a cor- ridor with each other, and with a central or administration building WOLFE ST. ^ ^ ]broa)dv^ay^ Fig. 26. — Plan of Johns Hopkins Hospital. A, Administration Building. B, Female Pay-ward. C, Male Pay-v/ard. D, Male Surgical Ward. E, Female Surgical Ward. F, Male Medical Ward. G, Female Medical Ward. B., Gynecological Ward. /, Isolating Ward. K, Kitchen. L, Laundry. 'N , Nurses' Home. 0, Dispensary. R, Patho- logical Building. »?, Stable. TJ , Amphitheatre. X, Apothecary's Building. Y, Bath-house. and other service buildings, the aggregation constitutes a modem pavilion block-hospital. The Johns Hopkins Hospital, already refer- red to, is a model of this class, and its plans should be studied in detail by all who are more particularly interested in hospital construction. 222 TEXT-BOOK OF HYGIENE. The general wards are in one- and two- story buildings, connected by a corridor with each other and with the administration and ser- vice buildings. In addition to two buildings containing private rooms and small wards for patients able to pay for the extra accom- modations, there is a line of paviaons running from east to west. The corridor cuts all the pavilions near the north ends of the buildings, separating the ward almost entirely from the service part of the building. This arrangement leaves the south, east, and west fronts of the wards entirely exposed to the sun's rays — a very important advantage. The kitchen and laundry are at opposite angles of the grounds, while the autopsy building is placed in the extreme north- east corner of the grounds, as far from all the wards as practicable. The free space between the separate pavilions should be at least twice the height of the building. In the Johns Hopkins Hospital, the space is 18 metres between the one-story common wards, which are 11 metres in height from the surface of the ground to the ridge of the roof. VENTILATION AND HEATING. The cubic space (initial air-space) per bed in the wards should not be less than 1500 to 2000 cubic feet (42 to 56 cubic metres), and for surgical or lying-in cases and contagious diseases, 70 cubic metres should be allowed. The ventilating arrangements should secure an entire change of the air two to three times an hour. In most sections of the United States, natural ventilation can be relied on to keep the air in hospital wards pure (assuming, of course, the proper construction of the buildings). The windows, doors, and walls are important factors in securing this ventilation. Hence, especial care is to be paid to their construction and arrange- ment. Many German, French, and English authorities on hospital building urge the importance of making the walls impervious by cement, glass, or paint. The peculiar odor known as ^Tiospital odor," it is asserted, cannot be prevented in any hospital in which the floors, walls, and ceilings are not absolutely impervious. The American practice is generally in favor of walls which permit transpiration of air. In the experience of the author the imperviousness of the walls is not necessary to secure freedom from hospital odor. It remains a question for serious consideration whether the diminution of natural ventilation would not counterbalance any good resulting from non- absorptive walls. VENTILATION AND HEATING. ' 223 The interior of the walls shouM be perfectly smooth and plain; no projections, cornices, or offsets of any kind are permissible. The desirability of this restriction was clearly expressed over a hundred years ago by John Howard : "From a regard to the health of the patients, I wish to see plain, white walls in hospitals, and no article of ornamental furniture introduced."^ Windows should run quite to the ceiling, and should not be arched, but finished square at the top. There should be one window for every two beds. The window-sash should be double to retain heat, and the lights heavy, clear glass. Ventilation can be promoted by raising the outer sash from below and lowering the inner one from above. The insertion of a Sherringham ventilator at the top of the inner sash will aid in giving the incoming air-current an upward direction. Heating is best accomplished by introducing hot air from without, or by stoves or fire-places in the centre of the wards. Where hot air is introduced from without, it should be heated by passing it over steam or hot-water coils, and not by passing it through a furnace, which may produce super-heating and excessive dryness of the air. In a series of experiments by Dr. Edward Cowles at the Boston City Hospital,^ the air was heated to 33° C. by passing it over steam- coils. It was admitted to the wards by numerous inlets 30 centimetres square. The best velocity for ventilating and warming purposes was found to be 54 metres per minute. Exit openings were in the ceil- ing, and it was found best to make them large, as by this means the rapidity of exit currents is reduced. Where the warming of the ward must be accomplished by stoves or fire-places in the ward, the best plan, for square and octagon wards, is to have a large central chimney with arrangements on the four sides for fire-places or stoves. This chimney can also be used as a very efficient ventilating shaft throughout the year by a device put in practice by Mr. John E. Neirnsee, architect of the Johns Hopkins Hospital.^ In oblong wards, two or more large stoves, placed at equal distances along the centre of the wards, will heat the wards effectually. Floors should be made of tiles, slate, or oak or yellow-pine lumber. If wood is used, it should be well seasoned, perfectly smooth. ' An Account of the Principal Lazarettos of Europe, etc., p. 57. London, 1791. ^Report of the Massachusetts State Board of Health for 1879, pp. 231- 248. ' Hospital Construction nnd Orcranization : Plans for Johns Hopkins Hospital, p. .3.3.5 et seq. New York, 187.5. ^ 224 TEXT-BOOK OF HYGIENE. and all joints accurately made. The floor should be kept constantly waxed to render it impervious to fluids. The space between the floor and ceiling below should be filled with some fire-proof non-conducting material, such as cement or hol- low bricks, in order to isolate each floor or ward, as much as possible from others, both to prevent transmission of noise and extension of fire. All corners and angles, on the inside of the building should be rounded to facilitate the removal of dust. In c.eaning up, care should be taken not to stir up the layers of dust too much by active sweeping and dusting. The floors, fur- niture, door- and window- casings should be wiped off with damp cloths. Soiled bedding, clothing, dressings, and bandages must be promptly removed from the ward. Mattresses and other bed-clothing should not be shaken in the ward.* Water-closets or (where the dry method of removal of excreta is in use) earth- or pail- closets should be placed where they can be easily reached by the patients, but the apartment in which they are placed must not open directly into the ward. The entrance to this apartment should be from the corridor or, better still, from the open air. The ventilation of water-closets should be independent of and entirely distinct from that of the ward or other part of the hospital building. It is, of course, unnecessary to more than call attention to the vital importance of the prompt removal of all excreta, both solid and liquid, from the ward or hospital building. To attempt disinfection of excreta and allow them to remain in the ward after being voided is a pernicious practice, which should under no circumstances be per- mitted. All utensils for the reception of excreta, bed-pans, etc., should be immediately emptied and thoroughly cleansed. Urinals are not advisable ; the simple hopper-closet with hinged, hard-wood seat, as described in Chapter VI, is sufficient. A bath-room and lavatory should be attached to every ward. It should be placed in the service building, and be easily accessible to the patients. There should also be portable bath-tubs in order that baths may be given in the wards when necessary. Every large general hospital should also have a special apart- ment or building where baths of various kinds, such as medicated, vapor, Turkish, and Eussian baths, could be given. In lying-in hos- *A. Wernich: Ueber Verdorbene Luft in Krankenraeumen. Volkmann's Samml. Klin. Vortr., No. 179, p. 24. VENTILATION AND HEATING. 225 pitals, special arrangements for giving vaginal and uterine douches must also be furnished. A daily water-supply of at least 450 litres per bed should be pro- vided. The water should be easily accessible from the wards and various parts of the service building. All water-closets, soil- and waste-pipes must be properly trapped ; all joints must be properly made and all sewer connections made on the most improved plans. All work of this sort should be properly tested before being accepted, and frequently inspected afterward. No sewer or house-drain should be laid under a ward. A disinfecting chest for disinfecting soiled clothing, bedding, dressings, etc., should be placed in the basement of the ward, and connected with the latter by an iron chute, closing perfectly by an iron top. The best and most convenient disinfectant is steam. This is also the best means to destroy vermin in clothing and bedding. It is questionable whether a nurse's room should be attached to a hospital ward. The nurse's place, when on duty, is in the ward itself, not in a room separate from it. Where there is a nurse's room, it should not be furnished with sleeping arrangements, for this is a strong temptation to neglect of duty on the part of the nurse. A nurse not on duty should not be permitted to remain about the ward. A ward-kitchen should be in the service building, where articles of food can be kept hot or cold when necessary, and where special dressings, cataplasms, hot water, etc., can be prepared. 'A small gas- stove only should be allowed in the ward-kitchen, as the regular meals of the patients are prepared in the central kitchen, which should be totally detached from the hospital. The ward-kitchen can be easily utilized as a nurse's room, and in a small hospital can also be used as a store-room for the patients' body- and bed- linen and clothing. The dining-room for patients able to be out of bed should be in the service building. A room with a good light and well ventilated and heated should be selected for this purpose. In the intervals between meals this room could be used as a day-room for such patients as should be out of bed, but who are not able to be in the open air. A dead-house, containing a dead-room, autopsy-room, and a room fitted up for rough microscopic and possibly photographic work, is a necessity to every well-appointed general hospital. The doad-house should be entirely separate from the ward buildings. The kitchen should be separate from the other buildings, and in large hospitals shoidd also bo the central station for the heating 226 TEXT-BOOK OF HYGIENE. arrangements, if hot water or steam is to be used. The laundry may be connected with it. The kitchen should be connected with the wards by means of a covered corridor to avoid exposure in carrying the food to the wards. The administration building should contain office-rooms for the superintendent and resident physician, pharmacy, library, reception- rooms -for visitors, living-rooms for one or more assistants, and dwell- ings for the superintendent and resident physician. THE ADMINISTRATION AND MANAGEMENT OF A GENERAL HOSPITAL. The general management of a hospital should be under the direc- tion of a superintendent, who, besides being a medical man, should be especially qualified by study and experience for the work. The super- intendent of a large hospital should not be expected to perform any of the routine professional work in the wards, but he should be re- sponsible for the service, both professional and lay, in the hospital. He should be the financial officer, and in all other things concerning the hospital his judgment should decide. He should have sufficient assistance to permit all necessary duties to be promptly performed. For this purpose he should have a secretary, or clerk, who should not be a medical man; otherwise the attention of the latter mighu be withdrawn from his clerical duties to the more interesting profes- sional work in the hospital. The plan advocated by some authorities, to have two superintendents for large hospitals — one of whom shall be a medical man and direct only the professional work of the hos- pital, while the other shall have charge of the administrative func- tions — does not commend itself to the author. It involves a division of responsibility which will, in nearly all cases, eventually lead to differences of opinion likely to prove unfavorable to the best interests of the hospital. It is customary in this country to appoint as resident physicians and surgeons in hospitals, recent graduates, whose functions are usu- ally limited to carrying out the directions of the visiting physicians and surgeons, and sometimes to act on their own responsibility in emergencies. This system has some advantages for the physicians, but is usually detrimental to the best interests of the patients. The resident medical officer in a large hospital should always be a thor- oughly qualified, experienced physician, capable of deciding promptly when the occasion arises, and he should be responsible to the super- ADMINISTRATION AND MANAGEMENT OF HOSPITAL. 227 intendent for the proper performance of his professional duties. Necessarily, a physician with the qualifications indicated, would de- mand a very much larger salary than is usually paid resident physi- cians, but it should be understood that no hospital in which the good of the patient is the first consideration can be conducted on a cheap basis. Visiting physicians and surgeons and all resident medical officers should be chosen with reference to their general and special quali- fications for the duties expected of them. It would seem to be a good plan to make the selections for subordinate positions, at least, by com- petitive examination. The sick in a hospital should be properly classified. Male and female patients should, of course, be treated in separate wards. A primary classification into medical, surgical, and obstetrical cases or wards is also indicated. Infectious diseases, such as typhoid fever, erysipelas, cholera, yellow fever, croupous pneumonia, etc., should not be treated in the same wards with rheumatism, Bright's disease, car- diac and nervous disorders, or simple digestive derangements. It is questionable, however, whether it is advisable to make a very elaborate classification of the various diseases except in very large hospitals. An accurate record, made at the time of observation, and not written from memory afterward, should be kept of the history and progress of every case. The record should show not merely the symp- toms and diagnosis, but the medical and hygienic treatment. In most hospitals where such records are kept the entries are made either in a simple memorandum-book or in a more or less complicated case- record. A simple form of case-record has been devised by Surgeon- General Walter Wyman, of United States Marine-Hospital Service, which seems to possess advantages that render its general adoption desirable. In hospitals where cases of surgical diseases and injuries are re- ceived, a special apartment should be fitted up as an operating-room. Operations should not be performed in a ward in the presence of other patients. QUESTIONS TO CHAPTER VII. CONSTRUCTION OF HOSPITALS. What would govern you in selecting a site for a hospital? What will go to determine the building area? In calculating the area required for buildings, what relation has it to the number of beds in the hospital? In the wards, what should be the actual minimum floor-space for each bed for non-infectious and for infectious diseases? What is the difference in the principles of modern hospital construction and of those formerly in vogue? What are some of the advantages of the modern plan? What was the pro- totype of the present system? How many wards should each pavilion contain at the most? How many beds in each ward? What conveniences should there be in each ward or pavilion? What is meant by a pavilion block-hospital? What space should there be between the separate pavilions? What cubic space per bed should there be in the ordinary wards? What cases need more, and how much? How often should the air be entirely changed in the wards? Should the walls be pervious or impervious to the passage of air? How should the walls be finished? How many windows should there be in each ward? How high should they be? \\'Tiat is the best way to heat a hospital ward? How should hot air be warmed? If a ward is to be warmed by fire-places or stoves, how should they be arranged? Of what materials should the floors be made? How should they be treated? Wliat should there be between ceilings and the floors above? Why? How should the corners and angles of floors and ceilings be finished? How should the wards be cleaned? What should be done with soiled bedding, etc. ? Where should the water-closets, etc., be located? How should they be ventilated ? How much water should be furnished per bed? Why should no sewer or house-drain be laid under a ward? Where should the nurses' rooms be? Where the ward kitchen and dining-room? What is the administration building for, and what should it contain ? What officers are necessary for the management of a hospital? What are their duties? How should the resident physicians be qualified and selected? How should the sick be classi- fied, and what wards should there be in a general hospital? Mention some of the details that should be noted in the case records. (228) CHAPTER VIII. SCHOOL HYGIENE. During the period of childhood and youth the organism yields readily to impressions and forces, both external and internal, and it is therefore important that the child be safeguarded during this forma- tive period, and surrounded with those influences which make for good. Considering the number of years spent in acquiring an education and the length of time each day devoted to study, most of which is spent in the school-room, it will be readily understood why a special chapter should be devoted to this particular theme. School hygiene includes the consideration of the sanitary principles underlying the construction of school-houses and school-furniture, ventilation and heating; the proper amount of time to be devoted to study at different ages; the special diseases of school-children, their causes, and means for their prevention. It also embraces the personal hygiene of the scholar and his g'eneral health and habits. These matters are of interest to the scholar himself, to his parents, the citizen in general, and especially to the physician; be- cause as a physician he is specially fitted by his special education and training to serve on school-boards and committees of education, and because he is so often called on to treat those maladies of child- hood which have been caused by unsanitary conditions in school life, or are largely influenced thereby. In the construction of school-houses the same hygienic principles are applicable as in dwelling-house construction. The selection of a site for the school-building should command the same careful con- sideration that is necessary in determining upon a site for a dwelling. It should be of sufficient elevation to insure good drainage, not only of the sewage and refuse collected in the building, but also of surface- and rain- water flowing over the soil. Proximity to marshes and other unsanitary surroundings should be avoided. If the soil is damp it should be properly drained, and all sources of insalubrity in the neighborhood avoided or, if possible, removed. Especially should there be plenty of space around the building to insure good external ventilation, to insure the admission of an abundance of light, and to provide ample play-grounds for the (229) 230 TEXT-BOOK OF HYGIENE. children. School-buildings should not be located in close proximity to factories, or to trades giving off smoke, dust, or noxious odors. School-houses should not be over three stories high; corridors and stairways should be wide, straight, and well lighted. All stairs should be securely built, and be guarded with ample, strong railing. All doors should open outward to permit ready egress and reduce the danger of accident in panics from any cause. Fire-drills should be held at stated intervals under direction of the teachers. In addition to the study- or recitation- rooms, provision should be made for play and calisthenic-exercise rooms. Well-lighted and ventilated side-rooms should be provided for the reception of out- side clothing, umbrellas, overshoes, etc. These articles should not be kept in the recitation- or study- rooms. Floors should be made of accurately-joined flooring, and ren- dered impervious by oil or paraffine coating. All corners and angles should be rounded, to prevent the accu- mulation of dirt. Appropriate measures must be employed to prevent the permea- tion of the building by ground-air. The foundation-walls should be laid in Portland cement, and coated inside and out with the same, and the floors should be laid in at least ten inches of cement. This will insure a damp-proof basement as well, which may be used as play-rooms during in- clement weather, provided they be properly heated and ventilated. The inside walls of school-rooms may be tinted a neutral gray, or light blue or green. Ceilings should be white. Walls and ceil- ings should not be painted, but lime-coated to permit free transpira- tion of air. Schools should be so constructed as to permit of ready heating and ventilation, cleaning, and keeping clean. In large schools the method will usually be by furnace-heated air, although a better method would probably be by steam- or hot-water pipes. What is known as the "Smead system" is a most excellent one. It is a combined system of heating and ventilation, consisting of a hot-air furnace, the fresh heated air being admitted through one set of registers, placed in the wall near the floor, and the foul air being taken out through another set of flues on the same side of the room and at the same level. This "used-up'' air is then carried from the building through a system of ducts passing beneath the floors of the rooms, the heat, by this arrangement, being further utilized to SCHOOL HYGIENE. 231 heat the floors as it escapes. In rural districts the school-room may be heated by means of a stove, provided with a jacket or cylinder surrounding it, and several feet in heidit. This is made of tin or Fig. 27. Fig. 28. Fig. 27. — a, a, Sash, b, h, Window-jambs, c, c, Window-sill. This cut represents the view from within the Bury Ventilator, in operation. It is broken away at one end to show the sash raised above the outer holes to admit the air. Fig. 28. — a, a, Sash. This cut represents the view from without the Bury Ventilator, in operation. The sash is broken away to show the ventilator behind, with the fresh air passing in. zinc. In the floor, beneath the stove, ho^es are bored to admit fresh air, which, warmed in passing over the stove, is deflected upward, and diffused, by means of the jacket. 232 TEXT-BOOK OF HYGIENE. The ventilation of school-rooms must be carried out on the principles indicated in Chapter I. With careful and intelligent teachers, natural ventilation will give better satisfaction than a com- plicated artificial system. Where windows and doors must be largely depended upon for ventilation, the Bury window ventilator, here illustrated, will give satisfactory results unless the school-room is overcrowded. Opening the doors and windows when the pupils are out of doors — flushing the rooms with fresh air — is not a method to be com- mended. The temperature of the room is so lowered, that when the children, overheated from play, return to it, they may become chilled, and "colds" be produced. A model study-room, according to modern views, should be about 9 to 10 metres long, not over 7 metres wide, and 4 to 4 ^/g metres high. Such a room could be easily lighted by windows on one side only, and readily heated and ventilated. It wouM also enable the teacher to exercise a close supervision over the pupils. In a room of this size forty pupils would be a proper number, although fifty could be accommodated. The initial air-space for each pupil would be 5.60 cubic metres if there were fifty pupils in the room, and 7 cubic metres if there were only forty. This would be slightly reduced by allowance for the teacher. It is believed that study-rooms should face toward the north. The light entering from the north side of a building would be equable during a whole day. While a larger window surface would be necessary than with an easterly or southerly exposure, it is held that the light, being devoid of all glare, would be more effective. When the light is admitted on the east, south, or west sides of the building, the direct entrance of the sun's rays must be prevented by curtains, by means of which the amount and proper distribution of the light is regulated with difficulty. The windows of the school-room should reach from about the height of the pupil's shoulder (when seated) to the ceiling. Arches or overhanging cornices over the windows should be avoided, as they cut off much light. For the same reason the near proximity of other high buildings and of trees should be avoided in selecting a site for a schoolhouse. The window area should be not less than one-fifth of the floor area, otherwise the light will be deficient. The light should be admitted only from the left side of the pupil. When admitted from the right side the shadow cast by the pen in writing interferes with good vision; if admitted directly in SCHOOL HYGIENE. 233 front of the pupil, the glare of the light will injuriously affect the eyes; while, if it can enter from behind, the book or paper of the pupil will be so much in shadow as to compel him to lean so far to the front in bringing his eyes nearer to book or paper that nearsight- edness is very likely to be developed. Furthermore, if the light is admitted into the room at the backs of the pupils, the eyes of the teacher are liable to suffer from the constant glare. In a school-room of the dimensions above stated, a row of windows on one side, forming an area of glass of one-fifth of the floor-space, will thoroughly and satisfactorily illuminate the room, with the least unfavorable influence upon the organs of vision. It is advisable, therefore, to always insist upon this arrangement of lighting of school-rooms. Where artificial light is used in a school-room, it should be in the proportion of one burner to every four pupils. All burners should be provided with chimneys and vertical re- flectors. Electric lights, properly shaded, or toned down with ground glass or tinted globes, are to be preferred, as they do not require any additional ventilation. Water-closets and privies should not be placed in cellars or basements. This would seem to be self-evident, and yet in many city school-houses these places of retirement are in this unsuitable loca- tion. When it is considered that large schools are frequently warmed by hot air taken from the cellar, it furnishes an additional reason to avoid this location for water-closets. On the contrary, the cus- tom, in some country schools, of placing the privy at a considerable distance from the school-room and in an exposed situation is almost equally reprehensible, as the pupils, especially girls, are prone to neglect obeying the calls of nature, from which neglect many dis- orders arise. These "garden-houses" should be connected with the school-house by a covered way. Desks should be slightly sloping, the edge nearest the pupil being about 1 inch (2.5 centimetres) higher than his elbows. The front edge of the seat should project a little beyond the near edge of the desk, so that a plumb-line dropped from the latter should strike the seat near its front edge. If the seat is not thus brought slightly under the desk, the pupil is compelled to lean forward in writing, which position prevents proper expansion of the chest and increases the bloofl-pressure in the eyes — a condition promotive of near- sightedness. Seats should be only high enough so that the feet rest flat upon 234 -TEXT-BOOK OF HYGIENE. the floor. If they are higher^ a foot-board must be provided. Children should not be condemned to the cruelty of having their feet dangling "between heaven and earth" while they keep their seats. Seats and desks should be graded according to the sizes of the pupils — not their ages or standing in the class. An ideal seat and desk would be one made to measure for each pupil, but this is manifestly impracticable, inasmuch as with the constant growth of the child the seats would be rapidly outgrown. Fig. 29. — Adjustable School-desk (Front View). The desk shown in Fig. 29^ is adjustable to children of differ- ent sizes, and seems to solve the problem which has so long puzzled the school sanitarian. The desks are made for a single pupil and the seat and desk are independently adjustable. The frame is of iron and the seat, back, and desk of hard-wood lumber. Blackboards should not be placed at a greater distance than 10 metres from the farthest pupil. The ground of the board should be a dead black, without lustre. In writing exercises upon the board, care should be taken that the letters and figures are made sufficiently large, and with rather heavy strokes of the crayon, in order that they may be easily seen from the most distant part of the room. It S. A. ' Made by the Rushville bchool Furniture Company, Rushville, Ind., U. SCHOOL HYGIENE. 235 has recently been demonstrated that a black letter on a white ground can be seen at a greater distance than a white letter on a black ground. Hence, it might prove advantageous to the eye-sight of school-children to substitute for the present blackboard and chalk, a white board and black crayon. In some European lecture-rooms this plan has been adopted with satisfaction. Young children should not be kept at the same study or in the same position for long at a time. The exercises should be frequently varied. It is especially with children in the primary grades that care should be taken not to overburden their minds with too many hours of study, or too long continuance at the same exercise. Children should not be placed in a regular school much, if at all, before the completion of their 7th year. Between the ages of 5 and 7 they may be sent to a kindergarten. From 7 to 9 years they should be kept at their studies not longer than three hours daily; from 9 to 13 years four hours may be allotted them; and from 12 to 16 j^ears they may be kept at mental work five to six hours daily. This does not mean that pupils are to be kept continuously at their studies during these hours, but that they should be neither com- pelled nor permitted to study longer than these periods each day. It is believed that these figures represent the capacity for endurance in the majority of children, and they should be adopted in all schools where the largest return in mental acquirements is desired at the least expenditure of health. Excess of time expended in study is almost cer- tainly followed by physical deterioration. "A little less brain : a little more muscle," for our children, is a legitimate demand that we may make of legislators and school-boards. . Gymnastic exercises should form part of the daily routine in all schools. These exercises should take place, when practicable, in the open air. Playing, romping, laughing, and singing should be en- couraged, rather than the natural tendency to boisterous play re- strained. It is especially desirable that female children should be encouraged to take part in these diversions. The desire, on the part of many parents, to see little girls deport themselves as young ladies, before the time even when they write their age in two figures, is very reprehensible, and deserves the most unqualified condemnation. Moliere's satirical remark, "II n'y a plus d'enfants,"^ seems to be . literally true at the present day. The principal diseases incident to school-life are myopia, spinal deformities, nervous and digestive disorders, pulmonary phthisis, and * There are no more children." 236 TEXT-BOOK OF HYGIENE. the comnmnicable diseases, viz. : chicken-pox, small-pox, erysipelas, measles, rotheln, scarlatina, typhoid fever, and contagious ophthalmia. By judicious sanitary measures these can all be very much diminished and some entirely prevented. It has been shown by the examination of the eyes of school- children that near-sightedness increases progressively from the low- est to the highest classes. Children who enter school with an hered- itary tendency to myopia, or who are, perhaps, already near-sighted Fig. 30. — Myopia According to School-classes — Boys. to a slight degree, soon become more intensely myopic; while others, who may be even hypermetropic on entering school, will be found to have become near-sighted during school-life. In examinations of over 30,000 pupils of grammar and high schools in Germany, Austria, Russia, and Switzerland, it has been found that the average pro- portion of near-sightedness is a fraction over 40 per cent., varying, in the different classes, from 22 per cent, for the lowest to 58 per cent, for the highest classes. These figures represent the averages of all the examinations made. In some particular schools, for ex- SCHOOL HYGIENE. 237 ample in the gymnasium (high school) of Erlangen, the percent- age in the higher classes was 88 per cent., in the gymnasium of Coburg, 86 per cent., and in the gymnasium of Heidelberg the pro- portion of myopic students in the highest class is said to have reached 100 per cent, in 1877. In the primary schools the percentage was found to be much lower. Eecent investigations in the schools of Stockholm, by Widmark, show that among school-children examined under 7 years of age there was no myopia. In the higher classes the myopia increases not only in degree, but in frequency. The diagrams, Figs. 30 and 31, show graphically the increase in degree and f re- Fig. 31. — Myopia According to School-classes — Girls. quency of myopia in the several school-classes. These observations show that the number of myopic individuals bears a constant relation to the intensity of use of the visual organs. The results of the obser- vation of different observers in different countries also uniformly point to the conclusion that not only does the number of near-sighted pupils increase as the higher classes are reached, but the degree of myopia increases likewise. Thus, a pupil who may have only a mod- erate degree of m3^opia on entering the school will have myopia in a higher degree as he advances in his classes. Erismann found, on re- examining the same pupils annually, that in six years 13.14 per cent. 238 TEXT-BOOK OF HYGIENE. of those examined had developed myopia from emmetropia, while in 24.57 per cent, of near-sighted pupils the degree of myopia had in- creased.^ The principal causes of the prevalence of near-sightedness in schools are badly-arranged or insufficient light, bad air, over-heating of the school-rooms, improper construction of desks compelling children to lean forward while reading or writing, and badly-printed text-books. The use of small type, poor paper, and bad press-work in text-books is very reprehensible. The type technically known as Long Primer is the smallest that should be used in text-books. That badly-arranged light and improper seats are causes of myopia has been shown by Forschutz in his examinations of the pupils in the public schools of Coburg. He found that in the newer schools, in which the light and seats are better arranged, the percentage of near- sight decreased. The average percentage of those examined in 1874 was 21, while in 1877 it had been reduced to 15,* showing the great improvement due to the application of correct sanitary principles in the construction of school-houses. Defective hearing has recently been shown to be especially fre- quent among school-children. A Berlin aurist found 1392 children out of 5902 (23.6 per cent.) suffering from ear disease of some kind. Dr. Samuel Sexton, of New York, and the late Dr. Chas. F. Percivall, director of music in the public schools of Baltimore, have arrived at similar results after examination of a large number of school- children. Spinal curvature is present in a large proportion of the children attending schools. Statistics are not very full upon this subject, but one author, Guillaume, states that he found lateral curvature of the spine in 218 out of 731 school-children — a proportion of 29.5 per cent. This, of course, includes the slighter degree of curvature, which cannot be properly termed a disease. Among 30,000 Danish school-children 13 per cent, had some variety or degree of spinal deformity. M. Eulenburg,^ found that among 1000 persons with lateral curvature of the spine, the disease began in 887 between the ages of 6 and 14; that is to say, during the years of school-life. Girls are affected more than ten times as often as boys, the proportion being 93.43 per cent, in the former and only 6.57 per cent, in the latter. - ' Erismann. Die Hygiene der Sehule, in von Pettenkofer und Ziemssen's Handbuch der Hygiene, "ll Th., 2 Abth., p. 30. * Quoted by Colin in Realencyclopfedie d. ges. Heilk., Bd. XII, p. 263. " Realencyclopaedie d. ges. Heilk., Bd. XI, p. 564. SCHOOL HYGIENE. 239 The especial causes of spinal curvature occurring during school- life are improperly-constructed seats and desks and an improper position of the body. Many pupils habitually assume a "twisted" position, which is very liable to produce spinal distortion in children of weak muscular development. The manner in which a desk that is too high for the pupil may produce spinal distortion is very well shown in Fig. 32. An improper position is more likely to be un- consciously assumed by girls than by boys. The clothing is respon- sible for this, for when the girl files into her place behind the desk, her clothing, hanging loosely about her, is swept back and forms a Fig. 32. -Showing Influence of a High Desk in Causing Spinal Curvature. pad, upon which she sits with one buttock. Another cause of this is a habit many girls have of sitting on one foot. The greater eleva- tion of her seat on that side throws the spinal column out of the vertical line, which is compensated by a partial twisting of the trunk. The attention of teachers should be directed to this faulty habit, which can be easily corrected, and its consequences averted by timely interference. Nervous disorders are comparatively frequent among school- children. Headaches are often due to insufficient ventilation, im- proper food, bad digestion, and excessive mental strain. Defective light may also be the cause of headaches by causing ocular fatigue. 240 TEXT-BOOK OF HYGIENE. Disordered menstruation in girls is a frequent cause which is not to be overlooked. Hysterical and imitative affections are not in- frequent, and sometimes pass through entire schools, including even the teachers. Girls are, of course, more subject to this class of dis- orders than boys, but the latter are not entirely exempt. Chorea is one of the nervous disorders which should debar the child who has it from school, not only on the child's own account, but also because the trouble may be transmitted to other children through association and imitation. Derangements of the digestive organs are exceedingly frequent among school-children. They can generally be traced to the use of improper food. The eating of cold lunches should be discouraged as much as possible. Nuts, candies, pies, fruit-cakes, bananas, and above all, pickles are most fruitful sources of digestive derangements of children. The absence of proper accommodations to enable children — especially girls — to answer the demands of nature are frequent sources of diges- tive and nervous disorders. The seeds of pulmonary consumption are frequently implanted during school-life. A neglected cough; bad ventilation, under which term may be comprised overheating and cold draughts, as well as polluted air; improper position of the body, excessive mental work, underfeeding, and the failure to exclude children who are the sub- jects of tuberculosis, may, any of them, be the starting-point of this fatal disease. Especial care should be taken to prevent the introduction or dissemination of communicable diseases through schools. The im- portance of this duty should be at all times impressed upon school- boards and teachers. In the first place, no child should be admitted within the door of the school-room unless it first presents undoubted evidence of protection against small-pox, either by having passed through a previous attack or by a proper vaccination. In case of an actual or threatened epidemic of small-pox the entire school, including teachers, should be vaccinated. Children should not be admitted to school coming from a house where there is at the time, or has recently been, a case of communi- cable disease, such as small-pox, diphtheria, scarlet fever, or measles. They should be excluded in each case for a period of time equivalent to the incubation of the given disease. It goes without saying that no child having itself been sick with a communicable disease should be admitted to school until entirely restored to health. SCHOOL HYGIENE. 241 -nj aq 6} sasraQ -dnj^ff JO Suiuui3 -aa'iuoij attifi, 13 XI w M H 60 O a ci P .2 ^ -U bS &» &> CQ CO J> -i-H i-H e3 aT e3 beS g^cS fQ rg r^ T-i 00 tH ^ , 1 02 . . to >. . . p>. c3 . . CS 'C . .T3 CO • .^ CI o • • O 4^ • +2 ^ ; £> I-H . . .^ .^ • 03 to . bDr- bjj • £i o3 S c3 ^ CO t^ 03 13 ^ - — -^ O ai -iJ >^ CO "1 'O O CO pd O ^ «£ c3 5? a • (-1 K 53 ri e3 '—^ ^d TS ^^r^ 1-1 (N r-l 1 ■ - — - to ! '^ ■ • >. • S^ •rS c« : .J> 1— t • O o • CO c- . ^ ^ • 0) aj • M,,, '=*rn" es ^1 C2 F-( ^ 'O ■ — ''O — -'O a.g . 33 CD 03 03 f>s p>^ &^. k. . ca 03 c3 a . .'d ■TS nd -c . f_l t- ^_^ :(M (N T-I o? • • o o O o • • 4S c- t^ Xt< c- : oT oT 03" (O • robcj5bJDE?bCE?bc^bC ^a >=a ba bn bfl ^=3,503^:8^03^03 03 • bO • bb- bC CO a cc a CO n bS bis bS 03 tH C3 (H 03 !h fO — ''C - — '^U '^ lO lO ! 03 t^ .t3 ' - 00 ^ : ^ r^ . . m 00 . 03 . o o ■ ,a ^ ^ : 03 •n • 53 rH . 03 J MORBIDITY AND MORTALITY IN SEAFARING PEOPLE. 293 Chart II. IJJ Ij IJJ Ijj fl-l 1-^ 294 TEXT-BOOK OF HYGIENE. The number of persons invalided from the service (including retirements of officers for disabilities and transfers to hospitals for the insane) was l.l-i-i, or about 3.8 per cent, of mean strength. Two hundred and eleven deaths occurred during the year, or 0.41 per cent, for disease and 0.26 per cent, for injury. Among the causes for ad- mission to the sick-list, malarial diseases stand first with 1,408 admis- sions, wounds ranking next with 942 admissions, while epidemic catarrh, which has headed the list for the last three years, falls to third place, with 877 admissions. Dengue fever adds 531 admis- sions. Eheumatic and diarrheal affections rank next in preva- lence, with 799 and 783 admissions respectively. The number of admissions for mumps and measles was almost twice as great as in 1901. The admissions for the epidemic diseases are: mumps, 330; measles, 245; diphtheria, 65; rubella, 48; small-pox, 23. Venereal diseases were as follows: Gonorrhea, 771; sj'philis, 606; chancroid. 284; alcoholism, 348. The total admissions for injuries of various character were 2,940, being divided among wounds, 952; contusions, 706; sprains, 612; fractures, 242; hernias, 175; burns, 171; luxations, 65; dro-RTiing, 27. Table XXXVI shows at a glance the numerical distribution of the eases among the sixteen classes into which, for convenience sake and statistical reasons, the diseases have been divided, while the two ad- joining charts will give a better idea (1) of the more prominent causes of death and (2) the prevalence in the Navy of the more spe- cial diseases and injuries. An example showing the enormous amount of work in marine sanitation done in various ports of the world, especially in the port of Hamburg under Dr. Nocht, of the detailed records that are kept and of the excellent and valuable statistical tables that are from time to time given to the medical world, the following will bear ample testimony: During the last seven or eight years there were under sanitary control : — I. In Cuxhaven: Table XXXVII. 1896 1897 1898 1899 1900 1901 1902 78 Disinfected -were . . 116 105 148 97 229 130 579 173 665 126 846 ships. 116 ships. MORBIDITY AND MORTALITY IN SEAFARING PEOPLE. 295 II. In Hamburg: Table XXXVIII. 1895 1896 1897 1898 1890 1900 1901 1903 19,359 16,375 15,458 13,218 14,099 14,430 17,708 19,302 ships During these examinations it was noted that the following num- bers of cases of sickness had occurred on board these vessels on the trip preceding their arrival in the port of Hamburg, namely: — Table XXXIX. 1895 1896 1897 1898 Internal .... External .... Venereal . . : 2,763 (143) 2,038 294 431 3,923 (144) 1,867 1,599 357 3,197 (122) 2,355 417 425 7,624 (105) 2.379 4,939 306 1899 1900 1901 1902 Internal .... External .... Venereal .... 9,805 (173) 3,554 5,932 319 10,789 4,818 5,631 340 14,365 6,087 7,221 1,057 15,163 cases 5,513 " 8,260 " 1,390 " Brackets ( ) mean deaths. Their distribution among the most important diseases was follows : — ■ as Table XL. Cholera Yellow fever Variola Diphtheria Malaria Typhoid Dysentery Consumption Scurvy Beri-beri Heat and heat-stroke. Heart disease 1895 5 (4) 40(24) 6 (2) 635 (5) 7 (2) 10 25(10) 37 (2) 5 (3) 83 (9) 1896 1 48(26) 3 1 961(12) 10 (3) 33 (5) 9 (3) 76(11) 17 (5) 54(10) 1897 2 (2) 6 (5) 1 1 807(20) 3 (2i 23 )1) 20 (2- 12 (1) 2') (7) 27 (7) 1898 2 (2) 1 584 (3) 7 (1) 12 (1) 11 (3 J 1 12 (4) 69(15) 15 (3) 1 3 1 547(27) 5 13 (2) 8 (5) 5 39(19) 27 (2) 23 (8) 1900 10 (8) 1 1 404(21) 6 (1) 10 (1) 13 (8) 12 U (8) 86(19) 23 (7) 1901 2 1 4 591(14) 33 (1) 25 (2) 20 (6) 35 1 4) 14 (8) 63 (3) 28 (5) 1902 14 (7) 5 (4) 3 4 O) 593(2^) 17 (6) 22 11 (2) 22 45 (3) 296 TEXT-BOOK OF HYGIENE. During the last three years the number of cases of sickness occur- ring among passengers on 138 steamers that came into tlie port of Hamburg was 3450. Two hundred and thirty-nine of these ended fatally and 1380 were infectious diseases: measles, scarlatina, rube- ola, diphtheria, variola, etc. On one ship two cases of plague occurred. Eelatively numerous are said to be abortions and uterine haemorrhages, caused by sea- sickness. On board these same steamers 4802 seamen received medical treatment; among these 389 cases were infectious diseases, with 25 deaths. The annual average number of sick seamen, derived from the records of the last eight years, as arriving in the port of Hamburg, is 2343, being distributed, likewise by annual averages, as follows: Internal diseases, 1047 ; external diseases, 795 ; venereal diseases, 553. According to the calculations of Dr. Nocht, every physician employed on these steamers, during a forty-days' trip, had under treatment, on the average, ten serious cases of sickness. Casualties and Disabilities Due to Shipwreck. — The total loss in vessels caused by shipwreck, during a period of ten years, amounted on an average, (1) in the English merchant marine, to 2.43 per cent.; (2) in the French merchant marine, to 2.36 per cent.; and (3) in the German merchant marine, to 1.86 per cent. In the German service the total loss of human life due to these accidents was 0.53 per cent, of the crews. The Seaman's Insurance Bureau at Hamburg, in its annual report for 1893, gives the following valuable information with regard to these casualties: — Table XLI. Accidents Reported. Vessels Number of Men Number of Accidents Accidents per 1000 Deaths per lOOO Steamers 24,636 15,595 1,277 1,423 636 5 57.76 40.79 3.93 6.09 Sailing vessels Employed 21.74 The Seaman's Insurance Bureau, in 1892, had on its books 43,023 insured seamen and paid insurance to 1668 persons. Out of this number the disability incurred by 1571 persons proved to be but temporary and lasted less than 13 weeks; of the remaining 97, 8 remained permanently disabled and the rest died. The total num- ber of registered sea-going vessels at the time was 2742 sailing ships, manned by 17,522 men, and 986 steamers, manned by 24,113 men. THE DRAINAGE OF SHIPS. Table XLII. Accidents Occurred as follows : 297 Year Number of Ships Number of Men Died Number of Passengers Died 1889 1890 1891 116 92 116 1,015 937 1205 208 169 177 331 174 160 274 7 30 THE DRAINAGE OF SHIPS. We say of a city or town that it is drained either according to the combined or the separate system, in accordance as to whether all the offal is discharged combinedly through one set of pipes, or whether the rain and the washwater are made to flow through a pipe system separate from this. In keeping with this nomenclature we may say of a ship that it is drained in accordance with the principles of the separate system. For, although the methods of ships' drainage are perhaps more complicated than are those of cities and towns, they, naturally, may be divided into two principal methods : — 1. The sea-water coming on board, the rain-water, the wash- water, the water circulating in the pipes of the flushing system, after passing through the various closets, the refuse from the kitchen, the ashes from the furnaces, are all made to pass overboard in the most direct ways. 2. The refuse matters from the engine- and boiler- rooms, those from the various magazines and storerooms, the rain-, sea-, and wash- water from the lower decks, all these find their way into the lowest and most dependent compartments of the ship by gravity, finally collect- iBg in what is known as the bilge-room. Thence the combined mix- ture, known as bilge-water, is pumped overboard by powerful station- ary suction-pumps. These suction-pumps generally terminate, with their open mouths looking downward, within a few inches from the bottom of the ship, being protected by wire gauze baskets to keep out solid matters. Their arrangement, while simple enough in a wooden ship, or even an iron merchant-ship, in a fully equipped modern battleship, the number of pipes of all sizes, their many valves and cross connections, are positively bewildering, and none but an expert can be entrusted with the laying out of a complete system in perfect and absolutely reliable working order. The drains are usually di- vided into main, auxiliary, and spcondary drains, according to size. The large fifteon-infh main drain on a big battleship is only used to 298 TEXT-BOOK OF HYGIENE. pump out very large quantities of water in case the ship's bottom is punctured; while the auxiliary drains are employed in pumping out the accumulated bilge-water at regular intervals, and the second- ary drains connect with the smaller local accumulations. The pumping and drainage system below the protective or water- tight deck of a modem man-of-war may be said to be divided into three parts, viz : emergency, surface, and double-bottom drainage. Each part is provided with separate and distinct piping, working independently, if desired, yet so interconnected with the others by means of valves that they all may be made to work in unison. The main drain (see Fig. 33) may be styled the emergency part, and consists of a pipe, ranging in size from by^ inches to 15% inches, according to the size and type of the ship, and extending from the after part of the forward fire-room to the after part of the after engine-room; its flanges are made water-tight on every main water- tight bulkhead it is made to pierce. The main drain generally runs on one, usually that side of the vessel where the center line longitu- dinal watertight bulkhead is fitted, throughout the length of the boiler compartments, branching ' j ' shape just aft of the for- ward bulkhead of the engine space, a branch being carried into each engine-room and connected to the main centrifugal pump in each of these compartments. In each compartment traversed by the main drain is a suction valve, the full diameter of the pipe, operated at the valve and also by means of a rod from the deck above. Branches from this main drain are led through the center-line bulkhead and fitted with valves at the end, so that all of the main machinery com- partments are connected directly to this large emergency drainage pipe. Each steam-pump throughout the machinery space, which in any manner is connected with drainage, has a suction connection with the main drain, so that one pump or all pumps may be made to work on this pipe whenever required to do so. The main drain is used only in case of an emergency, that is, when the water in any compartment is found to be rising above the floor-plates and cannot be controlled by the other drainage connections. Such an emergency would arise only on account of a vessel striking rocks or taking ground, thus injuring the inner bottom and causing a leak of great magnitude, or by a torpedo striking below the water line and injuring one or more watertight subdivisions. ■ OUTSIDE PLATING .DOCKING KetLS Fig. 33. — Cross-section of Ship, Showing Arrangement of Drainage System. (299) 300 TEXT-BOOK OF HYGIENE. By surface drainage is meant the drainage of all water that col- lects on top of the inner bottom in engine- and boiler- rooms, in store- rooms or other places throughout the whole length of the ship, not in double bottoms. Each watertight compartment throughout the length of the inner bottom has provided at its lowest part what is known as a bilge-well (see Fig. 33), that is, a rectangular, cup-shaped de- pression about 10 X 18 X 6 inches, worked into the inner bottom plat- ing. Into these bilge-wells the suction ends of all the suction pipes are placed, so as to provide the conditions for each compartment be- ing pumped as dry as possible. The principal pipe attending to sur- face drainage is called the "secondary drain" (see Fig. 33), to dis- tinguish it from the pipe called the "main drain." The secondary drain usually runs on the side of the ship opposite to the main drain, and extends from the forward end of the forward boiler-room to the after end of the after engine-room, connecting to a manifold (in other words, a series of valves cast in one chest) at each end and having branches leading to each bilge-well in every watertight compartment throughout the machinery space. Each steam-pump connected with the drainage system, except the main centrifugal circulating pumps, is provided with a suction to the secondary, and is so arranged that, by the manipulation of certain valves, any compartment may be pumped by any pump or by all pumps, if necessary. From the manifold, at each end of the machinery space, branch pipes extend to the several compartments forward and aft, so that the pumping of the several compartments forward and aft may be controlled from within the machinery space. The suction ends of all the branches within the machinery space are provided with Macomb strainers, and the suction ends outside of the machinery space are protected by perforated box-strainers, thus pro- tecting the piping as well as the pumps from becoming clogged by any extraneous matter. In addition to the secondary drain, the extensive functions of which may noAv be realized from the above description, a separate pipe, known as the independent '^Dilge suction" (see Fig. 33) is led from each steam-pump to the bilge-well of its own compartment, so that each compartment may, by its own pump, be kept dry without dirtying up the secondary drain. For pumping the crank-pit a small pump on the main shaft of the engine, known as the "shaft bilge-pump," is provided. This crank-pit, however, is also connected to the secondary drain and an independent suction, so that, in case the THE DRAINAGE OF SHIPS. 301 shaft bilge-pump is out of order, the water in the crank-pit may still be taken care of. The double bottom is either flooded or pumped through a pipe known as the "double-bottom pumping or flooding main" (see Fig. 33), which is a single pipe in boiler space and a single pipe in engine space, with a branch controlled by a valve leading into each water- tight compartment of the double bottom and with a connection direct to the sea and to one or two steam-pumps within the machinery space. The double bottoms throughout the machinery space are the only places provided with a flooding connection; while the double bot- toms forward and aft the machinery space have suction connections only, and are pumped by means of the secondary drain through the manifold in the forward boiler-room and the after engine-room. Summary. — From the foregoing brief description it will be seen that the main drain is an emergency drain, being used only to reduce large volumes of water; it is never brought into requisition for the purpose of reducing surface water. That the secondary drain, with its ramifications and auxiliaries, is employed to reduce all surface water usually collecting in the machinery space or such water as col- lects in holds or store-rooms, or for pumping out the forward or after tanks; finally, that the double bottom and flooding main looks after all water within the double bottoms. Ko suction pipes are led into the coal bunkers or magazines. Such water as collects under the floor-ceilings of the coal-bunkers is pumped out by means of a hose passed through the coal-bunker door. The magazines proper, without handling rooms, are pumped out after a flooding by means of a hose passed through a cap in the top of the magazine. In most of the wooden ships the bilge-room consists of a tri- angular-shaped space running along the entire length of the ship's bottom and inclosed between the bottom, the loose deck-planking, and the keelson (see Fig. 34). The numerous ribs of the ship divide this space transversely into a number of partitions, between which, how- ever, communications are established through borings, forming the so-called waterways (see Fig. 35). In iron ships, the ribs being fur- ther apart, these partitions are broader and more spacious, as well as deeper (Fig. 35). When double bottoms were introduced, and when these were used for the storage of iron tanks containing feed-water for the boilers, the bilge-spaces underwent a lateral displacement and came to be located between the inclinod planes of the ship's sides and tliose fco .s "El Si (303) L T O I u z IS « U bJ > ? u u. (303) PQ bo (304) *• iONGITUOINALS rig. 37.— STiowing Location of Bilge-spate on Top of Double Bottom. 20 (305) 306 TEXT-BOOK OF HYGIENE. of the double bottoms, where the}^ took the form of a shallow gutter (see Fig. 36). When, still later, the double bottoms were run up still higher on the ship's sides, these gutters disappeared and the bilge-spaces again were made to occupy the center line on top of the double bottoms (see Fig. 37). A further transverse division of the bilge-room occurred through the introduction of complete watertight bulkheads, running from side to side and from the bottom up to and through several decks, dividing these into complete and separate com- partments in a transverse direction and without any communication between them, except, perhaps, through watertight doors. Thus we see how the changes that have taken place from time to time in the methods of ships' construction have also materially af- fected the location of the bilge-spaces, and thus radically altered the composition and, consequently, the sanitary significance of the bilge itself. The old conception of bilge-water no longer holds good and needs a change. One of the principal sources of the bilge-water in wooden ships was the sea-water, which in all wooden ships leaked through the bot- toms. This water would accumulate in the most dependent portion of the ships' bottoms, where it would take up the offal from all sorts of cargo and provisions, the wash-water from the lower decks, the cadavers of small animals, dirt and dust from the sweepings, etc., etc. The whole would, in time, result in a thick, black, malodorous, fermenting fluid, filling the air with foul-smelling gases, splashing through the loose flooring laid over it, while the ship was under way, and soiling it and everything else in contact with it. On iron ships, the sea-water as the chief source of the bilge- water leaking through the ship's bottom is almost entirely done away with, for their bottoms allow no salt water to get through them. The only place through which salt water can still get into the bilge- room is the shaft-alley. The consequence is that, with ordinary care, it is possible to keep the bilge-room in these ships dry. Often the spaces between the timbers are filled with cement right up to the limber ho'.es (see Fig. 36), so as to guide the bilge-flow from one partition into the other and to prevent any accumulation in any of them. Thus, then, we will have to admit that what was known as the bilge on board the old wooden ships can no longer be considered the same thing on board our more modern iron ships. But still, differ- ent though it be in composition, the bilge will and must continue to receive the most careful attention and scrutiny of the ship's sani- THE COMPOSITION OF THE BILGE. 307 tarian, as remaining a source of contamination of the ship's atmos- phere, whenever it is allowed to accumulate and to undergo decom- position inside of the ship. Both chemical and bacteriological ex- aminations of the bilge will always have to be done, whenever the health of the personnel of a ship becomes a matter of serious concern. THE COMPOSITION OF THE BILGE. Notwithstanding the fact that bilge-water had always been looked upon by all classes of seafaring people as the most dreadful disease- breeder and as the most universal source of atmospheric contamina- tion on board all classes of ships, no serious scientific attempt at analysis was made until 1885 (Belli), when Nicati and Eietsch pub- lished the results of their investigations on the viability of the cholera bacillus in bilge-water. The possibility of importing this bacillus into Europe in bilge-water had been thought of, but the results of the experiments proved negative. A year later, Koch and Gaffky made some experiments on the disinfection of bilges and came to the con- clusions that mercuric bichloride was the most efficient means for the disinfection of bilges and bilge-water. In 1891 Forster and Eingeling published the most thorough and painstaking experiments that had been made on the subject up to that time. The most im- portant fact brought out by their experiments and observations was that the composition of bilge-water varied within the widest limits, not only in different ships, but also in different parts of the same ship, as is best shown in one of their own tables: — Table XLIII. Variatioms in Composition of Bilgewater. Dry Residue Combustible Substances Oxygen Con- sumed Chlorine Sulphuric Acid Ammonia 58-244.8 0.1-165.2 0.06-11.4 1.6-86.3 0.11-2.65 0.002-0.91 Interesting in this connection are the observations of Dr. ISTocht, which were published in 1893 and which are shown in the next table : — 308 TEXT-BOOK OF HYGIENE. Table XLIV Showing Composition of Bilge. Ship Where Formed General Properties Sail (wood) (( (( " (iron) Steamer (iron) i( (( Cargo-room t( (( Machine-room Cargo-room Machine-room Brown, turbid, muddy Black, turbid, very muddy Yellowish, clear, thick Clear, colorless Turbid, black, very muddy Opaque, colorless, no sediment Odor Beaction Chlorine per Litre Number of Germs per Cubic Centimeter Sweetish Neutral 9,585 325,000 Stinking Slightly Alkaline 12,780 100,000 No odor Strongly Alkaline 49,500 300 No odor Neutral 664 15,000,000 Foul Slightly Alkaline 10,615 3,000,000 No odor Neutral 5,573 4,600 Two years later Eingeling discovered two pathogenic anaerobes (septic vibrio and tetanus) in a portion of water taken from near the keel of a ship, and in 1896 Eocci, then surgeon in the Royal Italian Navy, studied the disinfectant value of milk of lime upon the most common bacteria found and isolated from bilge-water. The very latest and, at the same time, the most thorough and extensive examinations into the composition of bilge-water ever made are those published by Dr. Carlos M. Belli, of the Royal Italian Navy. These results are so important, especially as representing the facts as they exist on board men-of-war, that his tables have been in part reproduced. An examination of these tables shows that Belli employed the most up-to-date chemical, microscopical, and bacteriological methods in his work on bilge-water. Of quite particular interest are his inocu- lation experiments. He inoculated animals subcutaneously with samples of bilge-water amounting to ^/^ cubic centimeter for a dose, in order to ascertain whether they produced any possible pathogenic effect. In none of his many experiments was such an effect noted, although his animals were kept under observation for two months after being inoculated. He, moreover, tested the cultural properties of various types of bilge-water in both the natural state as well as after filtering it through Berkefield filters. As test-objects, 34-hour cultures of typhoid, cholera, icteroides, and staphylococcus pyog. aur, were used. Although the numerous and important details of this most extensive investigation on the composition of bilge-water must be UOJI J2^ • o : 01 c« a* 03 ■a u pions <1^ iz; H 03 H B o uaSojpXq a) d a ' a -jnqdins 1 ** "• 1 ■* ' o iz; " to s 1 ffl o o o o o o o S^BJ o ^ g s s s g g g o OS d d d o d d o ^ o o o ^ IC ^ lO o LO m ir ^ as irf rH i-^ d lH rH t~ 52 •^ CO iM -* -* lH lO I-t CO ■ stn i 1 O a 0! O o'~i Sa i Sfe^oSj; ^ 1 uotpBaa '2 ail -"A 2 "S << "3 ki 3 2 9j e 22. § h ■^ ■§ 0) <" -2 to 00 ^ ^ 00 i-i -^ Ml IC in OS S 'TS O =3 N t-' 00 OJ m d c4 e4 N S S5 "^ S ^ 2 ^ M Q* eo . > "S. p. "2 3 OS 2 2 3 3 ^ saonBJBaddy ^ ft 3 •i-^ 3 "2 2 3 3 ft^ «^ ^ ^ •£S >^ 3 h 3 3 S 2. 4> © = G Ho > H H HiJ > > m •* rf ^ 09 .2 to .2 ,d ^ joioo .3 C3 )i4 o M M o — O Q V J3 o 03 "5 .£) ua a a ^ O O n ^ ^ ■ m S io .2 'u "-^ 5 1 1 io sdiqs a OS o| 03 "a O^ 03 2 N 3 a " ,2 60 OJ2 « o o^ 73 O o-° es O ;^ O O ^ 3 O fi ■< g O O 93[ia JO ad^x h .9 a .q o a 1 _o > " o S CLi (309) 310 TEXT-BOOK OF HYGIENE. Table XLVI. Bacteriological Examination of Bilge-waler. ( Belli. ) Bilge-type Ships Average Number of Bacteria per c.cm. Species Identified Engine- room Monznmbano Calabria Dogali C. Alberto 239,000 2,141,000 984,000 307,000 Many colonies of chromogenic saprophytes ; some colonies resembling bacillus coli. Few hyphomycetes, and of the schizomycetes those common in sea water. Very few schizomycetes ; chromogenic cocci and few bacilli, of which fiuor liquefaciens are in greatest number ; few proteal. Numerous colonies of hyphomycetes ; of the schizomycetes, some colonies of cladothrix ; large numbers of chromogenic water coco and bacilli. Boiler- room Mon/ambano Calabria Dogali C. Alberto 362,000 1,016,000 3,289,000 1,000,000 Sparse number of fungi, many fluor liquefa- ciens. Mostly hyphomycetes and blastomycetes ; few species. Very large number of schizomycetes, common to engine-rooms. Sparse hyphomycetes; schizomycetes, common to engine-rooms. Provision- room Monzambano Calabria Dogali 652,000 333,000 1,261,000 Various colonies of proteal and pota'o-bacilli. Principally blastomycetes, less hyphomycetes. Mostly all blastomycetes; few hyphomycetes, some colonies of sarcina lutea. Table XLVII. 3Iicroscopical Examination of Bilge-water. {Belli.) Type of Bilge Ships Results Machine-room Monzambano Calabria Dogali C. Alberto Crystals of organic and inorganic salt, protozoa. Pretty large numbers of algae and protozoa, crys- tals, hemp- threads. Salt crystals, no living forms. Salt crystals, hemp-threads, no protistse. Boiler-room Monzambano Calabria Dogali C. Alberto Coal-dust. Coal-dust, no living forms. Coal-dust, few protozoa (ameboid and rhizopod forms. ) No living forms, sparse carbon particles and salt crystals. Provision-room Monzambano Calabria Dogali Mineral and vegetable dust, numerous rhizo- pods and flagellates. Salt crystals, vegetable fibres and grains, few protozoa. Vegetable fibres and hairs, ?alt crystals, no pro- tozoa. THE COMPOSITION OF THE BILGE. 311 studied in the original monograph in order to be properly appreciated, it would seem unavoidable to give a brief summary of the results in this place. 1. Bilge- water of the Engine-room Type. — To judge from the amount of chlorine which this water contained, it was concluded that the basis of it was salt-water mixed with a certain amount of sweet water derived either from rain-water or condensed water, added to which a variable amount of machine-oil was found. The relative proportions in the amounts of ammonia, nitrous acid, nitric acid, organic matters present; the absence, on the other hand, of sulphur- etted hydrogen, naturally led to the conclusion that the processes of decay in this type of water are extremely slight. This is, moreover, confirmed by the absence of bacteria, always present in decaying sub- stances. These waters possess no pathogenic properties. 2. Bilge-water of the Boiler-room Type. — The chemical analysis of the waters belonging to this type shows that, in ships lying at an- chor, these waters are preponderatingly made up of sweet water, formed in all probability from the feed-water of the boilers and part of which is spilled in the process of filling. In ships under way it changes its character from a sweet to a salt water. Here, also, pro- cesses of decay were absent. 3. Bilge-water of the "Cambuse" Type. — The chemical, micro- scopical, and bacteriological gharacters of this type were found to vary quite considerably. The sedimentary portion, under the micro- scope, showed small grains, fibers, hairs from planks, many forms of crystals, algae, and protozoa. The most common type resembled sea- water mixed with various contents from barrels. Acetic fermenta- tion was frequently present, while other processes of decay were absent. 4. Bilge-water of the Store-room Type. — This type of water is essentially a sweet water with which a small amount of salt water is mixed. It is probably for the most part rain-water. Processes of decay are here present constantly. It will be seen that, from the physical, chemical, and micro- scopical characters of these four different types of bilge-water, it is easy to distinguish one from the other; but even without taking these into account, it is still possible to distinguish the engine-room bilge by the oil with which it is mixed ; that from the boiler-room by the coal-dust or soot which it contains ; that from the cambuse by the acetic acid; and that from tbe store-rooms by the foul odor of the decaying substances which it contains. 312 TEXT-BOOK OF HYGIENE. From a hygienic point of view it is worthy of being emphasized that the different bilge-waters in battleships, especially those from the engine- and boiler- rooms, show either no evidence at all of decay going on in them, or that the evidence is present only to a very slight degree. This condition can only be the result of the better sanitary attention which these places receive on men-of-war, when contrasted with similar places on merchant ships. In the bilge-waters coming from beneath store-rooms, chemical examination, even here, shows evidence of advanced processes of decay in spite of the fact that the stores in question could not naturally be considered as very decay- able. One of the most interesting facts brought to light by the bac- teriological examination is this : that the engine- and boiler- room bilges of battleships contain either no proteae at all or their numbers are very small, while the store-room bilges literally teem with them. The persistently negative result obtained from the inoculation of bilge-water into experimental animals would indicate that, at least under ordinary conditions, these waters are free from both pathogenic germs and poisons. This, of course, does not exclude the possibility that, under other conditions, they might become the carriers of pathogenic germs, although, as has been shown, this danger even then would not be of long duration, since experiments have shown that the vitality of pathogenic germs in these waters rarely endures beyond five days. It was also found that the dirtier such water was, the less the chances of the survival of disease-producing germs would be. Altogether, then, it would seem, from an analysis of the total results of these investigations, as if the dangers to the ships' per- sonnel from the bilge-waters on board battleships had been slightly exaggerated, or could not, at any rate, be at all compared to what they are on ships of the mercantile marine. Such a result, it must, however, be remembered, can only l>e due to the strict sanitary super- vision accorded the bilges on men-of-war generally. Frequent cleans- ing of the bilges, aided by regular timely disinfection, must, in the end, be depended upon for rendering all kinds of bilges absolutely free from danger to the health of the men. THE SHIP. 1. Construction. — Desirable as it would seem, by way of an intro- duction into marine sanitation, to give a brief outline of ships' con- struction, space does not permit here to give more than the gross divisions of a typical vessel. Fortunately, the points regarding marine THE SHIP. 313 architecture that it is absolutely necessary for the sanitarian to know are few, and need hardly extend beyond a knowledge of the materials of which a ship is built, its various divisions and compartments and the special uses to which these are put, in order to enable him to suc- cessfully trace the sources of mischief to human life produced thereby. The marine sanitarian need not be a constructor, any more than the public health officer need be an architect or an engineer. For the marine architect by profession, the problem of construct- ing a small gunboat varies immensely from that of a large battle- ship, while for the marine sanitarian most of the problems that come within his province remain, fundamentally at least, the same in both cases. Thus, every ship of no matter what type or description is more or less damp, dark between decks, and difficult to ventilate thoroughly, so that it may safely be taken for granted that dampness, darkness, and poor air are the three main and most constant factors entering into every problem of ships' sanitation. When we add to these ex- treme heat for all large steam vessels of modern construction, we have indeed all the four elements against the influences of which sani- tarians must direct their principal efforts. The difference between merchant ships and warships grows wider every year. Thus, for instance, in a modern Lloyd steamer there are at present five decks. Beginning from above downward we have, first, the sun-deck; next, the promenade deck; third, the upper deck; fourth, the main deck; and fifth, the 'tween-deck. Below the last deck and abaft the engine-room there is the shaft-alley, and in the corresponding situation forward of the boiler-room we have the coal- bunk'ers and the various store-rooms for provisions. On the berth- deck, from bow to stern, there are the bunks for the steerage passen- gers, and also on the main deck forward of the smoke-pipe. The crew lives on the forward part of the upper deck, under the fore- castle. The first cabins and the rooms for the officers are on the promenade and upper decks. The cubic space to be allowed per man is nowadays prescribed by law in every civilized country, and usually amounts to 100 cubic feet, with a minimum floor area of 9 feet. This is said, especially by English surgeons, to be too small an amount, but, while admitting the justice of the complaint, as Kulenkampf and N'ocht have pointed out, part of the unhealthfulness of the quarters lies on the side of the interior arrangements of their living spaces, as well as in the insuffi- ciency of the available aic-space. ISTocht, in 1895, measuring 100 ships, found the amount of air-space allowed per man to be 125 314 TEXT-BOOK OF HYGIENE. cubic feet, that is, somewhat in excess of the minimum allowance re- quired by law. ISTocht, also, is of the opinion that internal cleanli- ness and a more judicious arrangement of the interior of the living spaces would be productive of greater good than an increase in the cubic capacity alone would be. Very different and somewhat more complicated and diiScult to understand than in a merchant steamer, are the various divisions and subdivisions of a modern first-class battleship. A large 16,000-ton battleship, complete in all its parts, in full motion and in action, approaches perhaps nearer to a colossal living organism than any other product of human ingenuity of recent date. To begin with, everything about such a vessel, that can be, is made of steel or iron, to resist not only the waves in the heaviest storms, but also the heaviest armor-piercing shot and shell. Fig. 38 is intended to represent, schematically, the main divisions of one of the latest types of a first-class battleship. It will be noticed that the thickest line in the drawing, running fore and aft and in- clining slightly at either end, divides the entire ship into an upper and a lower half. This line indicates the position of what is known as the protective or armored deck. All the other decks are above the protective deck, and below it we find all the store-rooms, boiler- rooms, coal-bunkers, engine-rooms, steam-steering rooms, magazines, ammunition passages, and trimming tanks. The different decks, from alcove downwards and extending be- tween the two military masts are the bridge, upper deck, main deck, gun-deck, protective or berth deck; with a flying bridge, situated above the bridge around the forward military mast. The berth-deck proper is that part of the protective deck which is continued in an even plane forw^ard and aft respectively from the protective deck, from the points at which the armored deck inclines downward for a short distance, forming an acute angle with the berth-deck. As a general rule, all the men's living quarters are on that por- tion of both the gun-deck and berth-deck which is forward of the after turrets, while the officers' quarters, with their mess-rooms, are on the same decks abaft the after turret. Iminediately beneath that part of the armored deck, included between the two military masts, are the engine-, fire-, and dynamo- rooms. Forward of the dynamo- room and abaft the engine-room respectively and between the pro- tective deck and the inner bottom, we have what are known as the upper and lower platforms, which carry stores and ammunition. Between the inner bottom and the outside plating there are the i7« M (315) 316 TEXT-BOOK OF HYGIENE. double bottoms. All the points marked W.T. on the drawing con- cern watertight bulkheads. Fig. 33 represents a vertical cross-section from the same type of ship as the preceding, through the boiler-rooms; the decks shown in this figure are the same as those shown in Fig. 38. In the boiler- room, to the left of the reader, may be seen the terminal of one of the large ventilating shafts, of the usual form, ending a little below the plane of the deck above and quite a little above the heads of the men. The lid shown in the figure attached to its lower end is to be closed in case forced draft is desired. When this lid is closed, the air is driven by the adjoining fan in a direction at right angles to the long axis of the shaft, and thence down into the boiler-room toward the furnaces, where it is intended to increase the combustion of fuel and the production of steam. The pressure which this forced draft arrangement is able to produce is said to be equal to II/2 ounces. On the right side of the sketch the ventilating terminal is shown to have a different arrangement. Here, the air is purposely shown to be carried down much further and, moreover, conducted to the sides of the room before being released from the main shaft. The figure was intended to show a flattened and perforated iron casing applied against the bulkhead through which the air was made to enter. This arrangement is proposed as an improvement from the hygienic stand- point, on the following grounds : In the first place, it is very desir- able to keep the cold air from pouring down upon the heads of the stokers and firemen, steeped in perspiration ; and, in the second place, the arrangement will give the admitted air a chance to do more ven- tilating work before it can make its escape through the centrally lo- cated exhaust pipe. In its passage from the sides of the room to the center it passes the breathing zone of the men at work, and this fur- nishes them with the necessary oxygen before escaping. The deeper down the cool, imprisoned air is carried in case of a hot room, the greater the distance which it will have to make while it becomes hot and rises, and the greater also its ventilating work will be before it can escape again. Beneath the boiler-room floor the figure shows some of the drains. On the extreme right may be seen the large main drain, nearest the middle line, where the bilge is located, there are the two independent bilge suction-pipes. The secondary drains, as well as the double- bottom floor and drain-pipes, may also be seen. Fig. 33 represents one side of a vertical section through the ship, where the eugine-rooms are ; the points shown in this figure are the same as those shown in the pre- ceding. THE SHIP. 317 The amount of cubic air-space for the living quarters of the crew, though still stingily dealt out on board many of the modern warships, may perhaps be regarded as all that can be expected under the present strenuous circumstances. With a crew of from six to eight hundred men on a battleship, with the constantly increasing number of officers required on board, and the ever-increasing addi- tions in new apparatus and machinery from year to year, the con- structor of such a ship has indeed a large contract on hand, if he is to furnish quarters for all, that are to be satisfactory from all points of view. From the point of view of sanitation, of course, if any one thing is more important than another, that thing is pure air. For no one can study thoroughly the history of sanitation in ships, its gradual and slow development in connection with life at sea and in ships, without coming to the conclusion that human overcrowding or its equivalent, bad air, has been the most constant and ever-present factor in contributing to render such a life unhealthful. Paradoxical as it may seem, it is nevertheless a fact recorded in history, that men in ships, at work below decks, have suffocated from want of air, while a gale of wind was blowing outside. The recognition by ship-builders and of all maritime nations of the present day, of the fact that a cer- tain minimum amount of cubic air-space should be allowed every living man on board and that an efficient ventilation, besides, is to be main- tained, may, therefore, with excellent reasons, be regarded as a signal victory over the conditions of the past and as the most important achievement of modern marine sanitation. Although there are no laws in existence in any navy with regard to the cubic air-space to be allowed per man on board a warship, such as are to be found for merchant vessels and to which the naval con- structor or commander is absolutely obliged to conform, the neces- sity for some definite allowance is, nevertheless, so urgent, that it practically always forms one of the important factors in the calcula- tions in the designs for every new vessel. The result, of course, as might be expected, is not a uniform one, varying with the indi- vidual ideas of the designer, all the way from 2 to 5 cubic meters, or from 70 to 175 cubic feet. Some very interesting, as well as instructive, calculations as re- gards the allowance of cubic air-space on board warships have been furnished us by Dr. C. M. Belli, of the Royal Italian Navy, quite recently. Belli, in his hygienic report on the second-class battleship Varese, has calculated with great exactness, as well as judgment, the actually available air-space per man under different conditions. ai8 TEXT-BOOK OF HYGIENE. Making due allowance for the number of men occupying the different sleeping quarters, and deducting the number that is always expected to be on duty in other parts of the ship under the usual routine in force, and which latter varies in accordance with the whereabouts of the vessel whether in port or at sea, he arrives at the conclusions shown in the succeeding table: — Table XLVIII. Sleeping Quarters O 3 Total Cubic Air-space in meters ^ si Gun-deck, forward . . 30 900 6.66 8 73 13.33 " " amidship . . 300 1,562 5.20 6.50 10.40 Berth deck, forward . . 20 161 8.05 10.60 16.10 " " amidship . 50 452 9.00 11.30 18.08 " aft ... . 50 234 4.68 5.80 9.36 Although the above calculations show a most generous provision of air-space and speaks well for the sanitary provisions made in the Italian Navy, calculations on the same principles as those made by Dr. Belli on other warships would no doubt reveal the fact that the actually available breathing space for the men is greater than the cal- culated air-space is. Notwithstanding, however, this deduction, it is also a matter of exact calculation that the available breathing-space on some of our own vessels does not come up to one-half of the al- lowance shown in the above table as existing on the Varese. 2. Cleanliness. — Our conception of the term "cleanliness" in general varies quite considerably at the present time from what . it was in prebacterial times. While, for instance, not many years ago, the surgeon was quite confident that his hands were clean when he had scrubbed them in soap and water, continued inquiry and investi- gation have convinced him since then that absolute cleanliness of the hands is practically unattainable. The methods employed for pro- ducing absolute cleanliness of persons and things are so complex and require so much professional knowledge that they will probably always remain in the possession of the professional few and never be mastered by the lay masses. Not long ago, a ship, for instance, was considered quite clean when its decks were soaked in salt water, its atmosphere saturated with moisture, and a smell of turpentine and paint permeated the living spaces. After an expensive experience of many years, we have THE SHIP. 319 •found out that a wet ship is not necessarily a clean ship; that damp- ness on board a ship is, indeed, one of the conditions favoring bac- terial growth and the perpetuation of epidemics. Still, it would not be hard to find a deck officer, even at the present day, on a modern ship, who would not express great astonishment if told that his clean- looking ship was nevertheless in a dangerously unsanitary condition. Much missionary work is yet required to generalize the knowledge of the principles of ordinary cleanliness. The problem of cleaning the decks of a ship is nearing its solu- tion on those vessels in which linoleum has been used for deck cover- ing. Here, the daily deluge with salt water has ceased to be neces- sary, and a moist wiping is both sufficient and effectual in producing the ordinary state of cleanliness. The atmosphere between decks has become much drier since this change occurred. But, unfortu- nately, there is still a considerable number of officers in the service who cannot get away from the antiquated system of giving the ship under their command a daily "ducking," and the sanitarian, there- fore, finds it still necessary sometimes to remonstrate. That the old fight for dry decks was really founded on good and sufficient grounds has been abundantly shown by the morbidity statistics. Friedel, quoted by Plimiert, compared the morbidity be- tween two English ships, the Centurio and the Conqueror. On board the former none but dry holy-stoning was practiced, while on the latter the decks were scrubbed after the usual manner, by a daily wetting with plenty of salt water and a more thorough weekly one. The morbidity records on the two vessels were as shown in the suc- ceeding table : — Table XLIX. Diseases • Centuro Conqueror Fevers 4 2 132 62 'i89 99 Pneumonia Catarrh of respiratory or, ans Sore throat 33 198 179 Dysentery Skin diseases 10 257 Summary 389 776 The medical officer, while rarely consulted with regard to the general method of keeping the ship clean, is often asked for sugges- tions when the bilge is to be cleaned. On this subject he should, therefore, bo able to give expert advice. The uKithod of treating the 320 TEXT-BOOK OF HYGIENE. bilge, in most cases, consists in a combination of the process of cleans- ing with salt water with some process of disinfection. In dealing with the bilge, it is by no means an indifferent matter whether the contents of the bilge are pumped out into the sea-water before being disinfected, or whether their disinfection is to be ef- fected first. The bilge-room may contain infectious germs which it is not safe to pass on into the waters in which the ship lies at anchor. Then again, the mixing of the disinfectant with the bilge-water, having to be done very thoroughly and so that all parts of the bilge will be brought into intimate contact with it, it will make consider- able difference in the result and the method to be employed whether the ship is under way or whether she lies quietly at anchor. When in motion all parts of the bilge-room will naturally be deluged with the disinfecting fluid ; when at anchor, an artificial circulation of the dis- infectant must be started with pumps and pipes. The fluid from the most dependent portion of the bilge, usually aft, must be pumped forward, whence it runs aft again by simple gravity, and thus circu- lates through the entire bilge space. In the experiments of Koch and Gaffke on the Freya and Hydne, the disinfecting fluid was first mixed with the bilge-water and, the ship lying quietly at anchor, the mixture was pumped from aft forward, thus causing it to circulate and become thoroughly mixed. After this disinfected bilge-water had been pumped out, enough disinfecting fluid was put into the bilge-room to make it rise to the same level occupied by the bilge-water previously disinfected and pumped out. The results obtained by Koch and Gaffke are summed up in the following conclusions: (1) With corrosive sublimate the most resist- ing bacilli may be destroyed; (2) corrosive sublimate must be added to the bilge-water in sufficient quantity to produce the reaction of mer- curic salt; (3) the mixing must be thorough; (4) the disinfection may be regarded as accomplished after an exposure of 18 hours; (5) after the bilge-room has been rinsed out four times, the amount of mercury remaining behind is so small that it is harmless. The strength of the solution to be empioyed is 7 : 2-3000 and salt water is the usual solvent. After the disinfection the bilge-room is dried and its floor and sides covered with minium paint. In the German service the bilge is cleaned in this manner once in two weeks. 3. Disinfection. — The naval surgeon is rarely called upon to su- perintend the disinfection of an entire ship. This is usually done at quarantine stations, where the necessary appliances and machinery will be found in constant readiness, with a trained personnel to run THE SHIP. 321 them. There are, however, many minor disinfections to be done on board every ship which the ship's surgeon must be prepared to exe- cute, and which, to do them well, require, nevertheless, a perfect knowledge of the art of disinfection and its practical applications in all the various branches on his part. While in civil life we may make a theoretical distinction between sanitary science and hygiene, or between a mere sanitarian (whose duty it is to prevent) and the hygienist or, in this case, the profes- sional disinfector (whose duty it is to remove the infection after it has invaded a ship), the naval surgeon must be both and cannot well afford to draw a strict line between these two functions if he is to do his full duty by his command. Besides, the whereabouts of war vessels are not always convenient to the regular disinfecting stations. A vessel, especially a war vessel, is rarely so badly infected as to need a disinfection throughout. There is no more reason for fumi- gating the hold of any vessel because a case of measles has appeared in the cabin or the steerage, than there is for disinfecting the base- ment of a tenement on account of the appearance of a case in one of the upper stories of the building. In a wooden vessel or iron mer- chant ship, with free communications between the various compart- ments, the danger of spreading any contagion throughout all parts of the ship is, of course, very great, but on a battleship, for instance, with its two hundred separate compartments, this danger is consider- ably less apparent. Of the utmost importance, however, is it to choose the proper method in special cases. In this respect, the naval surgeon finds himself frequently in a difficult position because of being obliged to devise both the means and the apparatus in order to gain his ends. He will then realize that nothing short of a thorough preliminary training in the principles and practice, of the art can ever help him out of the difficulty. Sometimes, the composition of the vessel to be disinfected will determine the choice of the method. A wooden vessel, for example, requires a most thorough mechanical cleansing and a longer exposure to germicidal agents than an iron one, in order to insure penetration and thorough disinfection, on account of the spongy nature of the wood, as compared with the smooth surfaces of iron plates. It is sometimes of as much importance to know what to disin- fect as how to do it. Thus, the cargo of a vessel is rarely infected except in case of plague, where the rats carry the infection into the deepest parts of the ships and bilges. The rats must be thoroughly 21 322 TEXT-BOOK OF HYGIENE. destroyed, and after their destruction so handled that the infection cannot spread from the cadavers. In the disinfection of living spaces it should always he rememhered that metal and all hright work are ruined by sulphur and bichloride and that, therefore, the use of for- maldehyde and carbolic acid must be resorted to instead. In using steam it must be kept in mind that leather and furs are ruined by it. When water-tanks are suspected of harboring the larvae of mosquitoes and the ship happens to be in salt water, the water may safely be pumped out, because the larvae, neither of anopheles nor of stegomyia, ever develop in salt water. When, however, the ship is in sweet water, petroleum should be first employed. In case the water-tanks are infected with the germs of cholera, typhoid, or dysentery, the water in them should in all cases be thoroughly disinfected or boiled by steam. A vessel kno-mi to be infected with yellow fever should always be given a preliminary fumigation with sulphur or pyrethrum powder, before being inspected, in order to either kill or benumb the infected insects and thus protect the inspectors. On the broadest general principles, while steam and formaldehyde must be considered the best agents for the disinfection of bedding and clothing, as well as living spaces, there are a number of infectious diseases that require special treatment and consideration. Thus, dur- ing epidemics of cholera special vigilance must be kept upon the water supply and the pipe connections ; in case of plague, it is to rats that we must pay special attention; in yellow fever, certain species of mosquitoes must be destroyed ; in ease of the exanthems, bedding, clothing, and the patient's skin must receive the lion's share of our efforts. In all cases alike, the ship's decks must be disinfected, since Belli has shown in an experimental study that the ordinary methods of scrubbing with either salt water or lye, as is commonly done, does not expedite the disappearance of infectious germs. The most important disinfecting agents that should be kept on hand aboard every sea-going vessel are sulphur, steam, formaldehyde, lime, bichloride of mercury, and, of late, coke must be added to the list. Sulphur, for some time in disrepute, on account of its lack of penetrating power and its failure to kill spore-bearing germs, has re- cently regained part of its lost prestige, since it became known that it kills mosquitoes and other disease-bearing animal parasites. The best method for ships' use is the iron-pot method. The sulphur U usually used in lumps that are saturated with alcohol and then lit. Five pounds of sulphur for each 1000 culiic feet of air-space pro- duce a 5 per cent, gas, which is sufficient to kill all non-spore-bearing THE SHIP. 323 organisms within sixteen hours. Care should be taken that the articles to be treated by this method are not too dr3\ Steam is perhaps the most widely used disinfecting agent, as well as the most valuable of any used on board ships. Steam-pipes may be found conveniently located in almost any part of a ship, and can be tapped for a supply of steam. In case no regular steam dis- infecting apparatus is at hand, such an apparatus may be extemporized and made out of a vinegar or wine barrel or some iron water-tank. Streaming steam has the same power as boiling water, and an exposure of half an hour is generally sufficient to kill very resisting spores. It may, therefore, safely be used and depended upon for destroying the infectious agents of any of the communicable diseases. It should be remembered that steam shrinks woolens and injures silks, it ruins leather, fur, skins of all kinds also rubber shoes, mackintoshes, and other articles of impure rubber. Formaldehyde. — A gas is, of course, the ideal form of a disinfect- ant, and formaldehyde comes, perhaps, nearer to that ideal than any other gas, in spite of the fact that it has some very decided limitations, not the least of which is its lack of penetrating power. Solutions, unless immersion can be maintained for a long enough time without injury to the material, are not so valuable. Several years ago, von Esmarch devised a method by means of which it was thought possible to eliminate the shortcomings of both steam and formaldehyde. The method aimed at a combination of steam and formaldehyde in a chamber in which the air was rarified at the same time. By adding the vapor of formaldehyde to steam it was hoped that steam might be used at a lower temperature than 100° C, and thus its injurious ef- fects on some of the fabrics be eliminated. By causing a partial vacuum in the disinfecting chamber it was hoped that the penetrat- ing effect of formaldehyde could be materially increased. Ivister and Trautmann, in some recent experiments with von Esmarch's method. made with the object of testing its applicability on a large scale, ob- tained results that were not quite as promising as they had been led to expect. Although the combination of steam with a 3 per cent, atmos- phere of formaldehyde gave evidence of increased disinfecting power, it was noted that the m.ixture, at a temperature of 75° C. and under a reduction of the pressure equal to 520 millimetres, failed to kill all the spores and did not uniformly penetrate all parts of the cham- bers. The method, however, seems promising, and its further perfec- tion will be only a matter of time. Formaldehyde occurs in the market in several forms. The 40 per 324 TEXT-BOOK OF HYGIENE. cent, solution is known as formalin, and this is sometimes used for the generation of the gas in a special generator. Ten ounces of this fluid are considered quite sufficient for each 1000 cubic feet of air-space. Sometimes the gas is developed directly from wood alcohol. When the vapor of wood alcohol is passed over incandescent platinum, the alco- hol is reduced to an aldehyde. By the use of the Kuhn lamp three pints of wood alcohol may be reduced in two hours, and the amount of gas thus produced is said to be sufficient for the disinfection of 1000 cubic feet of space. For the purpose of disinfecting clothing in a trunk, which often needs to be done when officers return from leave of absence and report infectious diseases in their families, not less than 50 cubic centimetres of formalin for each cubic foot of space is required. (Eosenau.) Mail matter is ordinarily disinfected by clipping the corners off the envelopes and introducing a few drops of formalin with an eye-dropper, and several drops are also put on the outside cover and the whole shut up in a tight box, which is then placed in a warm room for six hours. The box should be opened out of doors. Formalin is also a convenient disinfect- ant for urine, excreta, and sputum, because of its possessing the property of combining with the albuminous matters without causing their coagulation. On account of its nontoxic properties it is, more- over, often employed in the disinfection of food-products. Large quantities of bulbs, roots, nuts, fruits, and similar articles, coming from infected districts, are treated by immersion into a 5 per cent, solution of formalin without harm. Bulbs so treated keep from rotting for a long time. Lime. — Milk of lime, which is slaked lime mixed with about four times its volume of water, is one of the most useful disinfectants for excreta and privy-vaults. Chlorinated lime, in the United States Army officially prescribed in the form of a 4 per cent, solution for use in the disinfection of the excreta from the sick, combines the effect of both lime and chlorine. When used for ships' holds or rooms, l^/o pounds of it mixed with 6 ounces of strong sulphuric acid are supposed to be sufficient to produce the purification of 1000 cubic feet of space. As is the case with sulphurous acid, chlorine gas acts more energetically in the presence of moisture. Mercuric Chloride. — One of the most popular of the disinfect- ants is mercuric chloride. A solution of 1 : 1000 will surely kill all spore-bearing organisms at ordinary temperature within half an hour. Articles of clothing may be thoroughly disinfected by immersion into THE NAVY RATION. 325 a solution of 1 : 2000 for two hours; a solution of 1 : 15,000 inhibits both fermentation and putrefaction. Carbon Monoxide. — In carbon monoxide we possess one of the most efficient gases for the destruction of rats in ships. Nocht and Giemsa have recently devised an ingenious apparatus in which the gas is produced by the incomplete combustion of coke. Part of the heat produced by the combustion is used to furnish the steam necessary for running a water-pump and ventilator. The gases resulting from the combustion of coke are heavily charged with carbon dioxide, the pressure of which prevents them from forming an explosive compound when mixed with air. This protective action of CO, is secured when the latter reaches an amount equal to twice that of the carbon monoxide content. As determined by the apparatus of Orsat, the composition of the gaseous mixture produced in the generator is CO, 4.95 per cent. ; COg, 18 per cent. ; and N., 77.05 per cent, by volume. Four hundred and five cubic metres of the gas can be produced in one hour. The gas has a specific gravity of 1085. Before beginning the disin- fection the men must leave the ship. In order to kill all the rats in a ship, it suffices to generate an amount of gas which equals one-half to three-quarters the capacity of the ship. The process of disin- fection being over, all that is necessary, in order to get rid of the gas, is to start the ventilators and open the hatches. This may be done after an exposure of six hours. Mice are used for testing the atmosphere for CO. These ani- mals, which are very sensitive to CO, must be found alive after a two- hours' residence in any compartment, before the ship is pronounced safe for re-occupancy. The method is not only reliable and thorough, but also quite inexpensive. THE NAVY RATION. While it cannot be expected, in the limited space allotted to this article, that we enter at all into the special physiology of nutrition or into the chemistry of food-stuffs, it is, on the other hand, unavoid- able and necessary to touch upon those of the leading principles and methods according to which the nutritive values of those of the food- substances that are in common use on board sea-going vessels, and included in the navy ration, are ordinarily determined. In the ordinary walks of life a man chooses not only what articles he eats, but also how much of these he thinks he needs, and the free play of his instincts generally leads him to select from a bill-of-fare the diet best adapted for his maintenance. In naval and military 326 TEXT-BOOK OF HYGIENE. organizations tliis free choice or selection as regards a man's diet is greatly limited, inasmuch as the latter is provided for him by some one else. Hence it will readily be seen how very important it is that this provided diet should answer in all respects to the full require- ments of the average working man. The diet-list made out on board ship ought to differ, therefore, from an ordinary bill-of-fare, in giving, upon careful examination, the results characterizing a perfectly constructed and in every respect complete meal. The meals for the day, to be called perfect, must show that they contain in proteids, fats, and carbohydrates not only the proper amounts, but also the right relative proportions of each. When the examination shows that this is the case, then our list of articles ceases to be a mere ''bill-of-fare" and becomes a ''ration/' intended to meet all the required needs of the normal, working human organism for a period of twenty-four hours. Since the distribution of the different articles of food-stuffs, on board ship, at any rate, is left to the commissary yeoman, a man not generally in possession of the knowledge required to perform that duty according to the best prin- ciples of the physiology of nutrition, and since, moreover, the influ- ence of the continuous faulty distribution of food-stuffs upon the larger number of men must prove disastrous in the long run, it be- hooves the sanitary officer to keep an eye on the diet of his men and correct any mistake made in this respect. He should, therefore, be familiar with the methods employed to determine the food values of any diet, as well as know when a diet is complete in all respects, and when it is not. The food value of any edible substance is generally expressed by the number of calories or heat units which one gram or any other definite quantity of it will develop when completely burned in a calorimeter. The amount of heat that is developed during the com- bustion, for instance, of one gram of a substance in a calorimeter is exactly the same that is produced when one gram of the same sub- stance is completely oxidized within the body. In a living organism about 30 per cent, of this value can be put out in the form of me- chanical work, while the remainder passes off in the form of heat. We know, thanks to the researches of Voit, that an average adult laborer performing his daily work puts out in mechanical work and heat the equivalent of about 3000 calories. In order, therefore, that the man shall not lose his weight, his daily diet must be such as to balance his loss and have a combined caloric value of at least 3000 units. If we furthermore take into calculation that about 400 of these THE NAVY RATION. 327 units, at least, must come from proteids, 500 from fats, and the re- mainder from carbohydrates, we have the most necessary data for the calculation of the man's diet. Thanks to the labors of Voit and Eubner and their numerous pupils, these determinations have been greatly simplified in recent years. Outside conditions, personal and racial habits, climate, age, and sex may alter the relative proportions of proteids, fats, and carbo- hydrates in a certain diet; but the above proportions must stand as answering to the average requirements of an adult workingman in a temperate climate. In calculating the dietary value of a ration we must also allow for an unavoidable loss in the preparation of the differ- ent parts of it. In meats a loss of 20 per cent, of the raw material is generally allowed for bones; in salted herring, 37 per cent. ; in pickled herring, 29 per cent. Potatoes boiled and then peeled lose 7 per cent. Potatoes peeled raw lose 30 per cent. In the case of eggs 10 per cent, in weight is deducted for the shells, etc. Another source of loss from the gross weights is in the different degrees of digestibility of foods, for which allowance must also be made. As a general rule, animal foods are much more completely digested than foods of vegetable origin. Eubner has shown that the proteids from meat and milk dis- appear almost entirely, while those from bread, and especially vege- tables, reappear in the feces in considerable proportions. A simple and approximately accurate method for calculating the nutritive value of a diet has recently been published by Schumburg. He makes a slight difference in the food value between animal and vegetable proteids, giving the former a value of 3.5 and the latter a value of 3.1. The fats have a value of 8.8 and the carbohydrates one of 3.7. Given, then, the various constituents of a diet, expressed in proteids, fats, and carbohydrates, their weight stated in grammes, multiplied by their respective values, the several amounts added to- gether would give a sum corresponding to the total food value of a diet in numbers of calories or nutrient units. Kemembering that a sufficient diet for an adult workingman must have at least 2000 nutrient units, and that the proportion of proteids, fats, carbohydrates, and salts in a complete diet should be as 150, 100, 500, and 35, we should have an easy and simple method of ascertaining and con- trolling the dietary value of any meal. It is on these principles, and with the aid of the usual tables of the food values of the different articles entering into the composition of a diet to be found in every work on physiology or hygiene, that the following diet table of the new naval ration has been worked out. 328 TEXT-BOOK OF HYGIENE. A reduction of about 35 per cent, of the quantity of every article in the table, with the exception of the usual quantities of bread, but- ter, coffee, milk, and sugar, was made for certain necessary and un- avoidable waste which occurs in their preparation. In calculating the food values of the customary quantities of bread, butter, coffee, milk, and sugar which are served out at every meal, the value of coffee as a food was disregarded. It may be added that the coffee is replaced, especially for supper, by cocoa or tea. Table L. Diet table prepared from one wee¥s allowance of the neio United States naval ration. SUNDAY. Weight in Grams Contents in Grams In Nutrient Units Food Allowed Protein Fats Carbohy- drates ProteiQ Fats Carbohy- drates Sum. Breakfast: Baked beans 135 90 32.8 15.8 2.0 19.8 66.2 101.7 55.3 17.6 174.2 244.9 364.2 229 5 Pork Catsup 16.8 19.9 170.7 52.6 175.1 631.6 859.3 Sum 209.6 366.9 876.5 1 453 Dinner : Roasted veal 360 270 72.2 5.4 32.4 .5 252.7 16.7 285.1 4.4 537 8 Potatoes, mashed. . . . DressinR 55.9 206.8 227.9 16.8 19.9 1:0.7 52.6 175.1 631.6 859.3 Sum 1 t 322 464.6 8 8.4 1 625 Supper: Ham, boiled 1^0 112 27.5 .2 16.8 r2.o "19.9" 96.2 457.6 .6 52.6 175.1 553 8 J.lly 36 170.7 133.2 631.6 133 8 859 3 Sum 149.4 632.7 764.8 1,546.9 Total nutrient units in day's ration, 4,625. MONDAY. Breakfast : 90 ISO 10.8 17.1 16.8 4.0 136.8 19.9 5 .2 33.5 63.3 52.6 35.2 1 203.8 175.1 19.3.1 261 8 Bacon, fried 1 267 1 1:0.7 631.6 859 3 Sum 149.4 1,414.1 824.7 2 388 2 Dinner : Beef, roasted 360 1£0 80 3 41.0 IK. 8 7.2 102.9 3.2 19.9 .7 281.0 127.1 52.6 22.3 90.3.5 28.2 175.1 6.2 1 186 5 94.3 170.7 74.5 348.9 631.6 275.6 504 2 Bread, butter, etc. . . . 859 3 Potatoes 360 304.1 Sum 483.0 1,11.5.0 1,256.1 2 854 1 Supper : Cold beef. ISO 10 iO 40.1 11.7 .4 16.8 51.5 1.8 "lb. 9" 140.3 36.3 1.2 52.6 453.2 15.8 "iVs'.i' 593 5 Pudding- m.3 86.8 170.7 522.8 323.2 631.6 574 9 324 4 Bread, butter, etc. . . . 859 3 Sum 230.4 644.1 1,477.6 2,352.1 1 Total nutrient units in day's rations, 7,594.4. THE NAVY RATION. 329 Table L — (Continued.) Diet taUe prepared from one week^s allowance of the new United States naval ration. TUESDAY. Weight in Grams Contents in Grams In Nutrient Units 1 Food Allowed Protein Fats Carbohy- drates Protein Fats Carbohy- drates Sum. Breakfast : Hash— 180 345 " 45 27.5 6.9 .8 16.8 52.0 .7 .1 96.2 21.4 2.5 52.6 172.7 457.7 6.2 .8 175.1 553.8 71.4 4.6 264.2 17.0 631.6 291.8 20.3 19.9 1 170.7 859.3 639.7 912.8 1,725.2 Dinner : Soup — 90 360 45 90 21.9 63.0 .6 1.4 79.2 .1 44.1 67.9 220.5 1.8 12.3 697.0 .8 163.2 243.4 Pork 917.5 Tomatoes 2.0 7.4 10.0 16.8 19.9 1 170.7 52.6 175.1 631.6 859.3 342.8 885.2 802.2 2,030.2 Supper : Stew— 360 90 15 45 180 6.8 7.8 ' '".2" 40.1 16.8 1.2 .9 12.2 ' 51.5' 19.9 11.9 67.0 21.0 24.2 10.6 7.9 107.4 ' 453.2' " 175.1 44.0 247.0 75.6 279.1 107.4 43.4 .6 140.0 52.6 161.6 162.2 593.2 170.7 631.6 859.3 Sim 238.4 754.2 1,034.2 2,076.8 1 Total nutrient units in day's ratidn, 5,832. WEDNESDAY. Breakfast : 180 90 43.8 15.8 2.8 19.8 88.2 135.8 55.3 24.6 174.2 326.3 486.7 Pork 229.5 16.8 19.9 170.7 52.6 175.1 631.6 859.3 * 243.7 373.9 957.9 1,575.5 Dinner: Sausages (Frankfort) . 225 500 270 180 39.4 8.0 3.5 3.5 16.8 90.0 1.5 .5 .4 19.9 1S7.9 24.3 10.8 10.8 52.6 792.0 13.2 4.4 3.5 175.1 929.9 28.0 21.9 37.3 170.7 103.6 81.0 138.0 631.6 141.6 96.2 152.3 859.3 236.9 988.2 954.2 2,179.3 Supper : 110 45 10 45 110 9.9 14.0 24.5 16.8 .5 11.0 8.4 .1 31.6 19.7 84.7 1.0 30.7 49.0 4.4 96.8 73.9 .8 278.0 175.1 313.4 3.7 348.5 149.5 73.9 2.0 1.5 85.7 52.6 7.4 9.7 Beef, comed 363.7 170.7 631.6 859.3 219.5 629.0 956.1 1,804.6 Total nutrient units in day's rations, 5, .5.59. 4. 330 TEXT-BOOK OF HYGIENE. Table L. — {Continued.) Diet table prepared from one week^s allowance of the new United States naval ration. THURSDAY. Weight in Grams Con tents in Grams In Nutrient Units Food Allowed Protein Fats Carbohy- drates Protein Fats Carbohy- drates Sum. Breakfast : Slew- Beef 1?0 270 45 30 25 40.1 5.5 .6 .4 .3 16.8 51.5 .5 .2 19.9" 140.0 17.0 1.5 1.5 1.0 52.fi 453.2 4.4 1.7 ' 175. i' ' 593 2 Potatoes Carrots 5.5.9 5.0 3.0 1.0 170.7 206.8 18.5 11.1 3.7 631.6 228.2 21.7 12 6 4 7 859.3 213.6 634.4 871.7 1,719.7 Dinner: 360 110 135 180 56.1 1.8 L7 3.5 16.8 94.3 .1 .3 .4 19.9 196.0 6.0 5.5 in. 8 52.6 829.8 .8 3.0 3.5 175.1 39! 5" 40.7 1.38.0 631.6 1,025.8 46.3 Beets 10.7 11.0 37.3 170.7 49.2 152 3 859 3 1 1,012.2 849.3 2,132.9 ,„ Supper : Rice 110 72 80 7.2 6.0 .4 1.1 6.0 86.4 22.3 21.0 1.2 9.6 52.8 819.6 351.5 EgM 73 8 77.2 285.6 286.8 Beef, corned, c Id . . . 135 21.0 16.8 35.4 19.9 73.5 52.6 311.5 175.1 385.0 170.7 631.6 859 3 270.6 549.0 1,236.8 1,956.4 Total nutrient units in day's ration, 5,809. FRIDAY. Breakfast : Ham 180 315 22 27.5 6.3 .1 16.8 52.0 .6 "19.9" 96.2 19.5 .3 52.6 451.6 4.4 ' 175.1" ' 547 8 65.2 2.0 170.7 241.2 7.4 631.6 265 1 7 7 859.3 168.6 631.1 880.2 1,679 9 Dinner : Mutton, roasted Peas 360 180 16 360 273.6 41.0 1.2 7.2 16.8 61.2 3.2 1.3.8 .7 18.9 21.6 94.3 .1 74.5 170.7 957.6 127.1 4.0 22.3 52.6 544.0 28.1 118.8 6.1 175.1 79.9 347.8 .3 277.6 631.6 1,581.5 503 Butter 1231 Potatoes, mashed 306.0 859.3 Sum 1,163.6 872.1 1,337.2 3 372 8 Supper : Salmon 270 90 57.2 .7 16.8 34.6 ' 19.9' ' 2C0.2 1.4 52.6 304.5 ' 175.1' ■ 504 7 Fruit, canned 7.2 170.7 26.6 631.6 2 .0 859.3 Sum 254.2 479.6 658.2 1 392 Total nuirient unils in day's ra'ion, 6,444.8. THE NAVY RATION. 331 Table L. — {Continued.) Diet table prepared from one week's allowance of the new United States naval ration. SATURDAY. Weight in Grams Contents in Grams In Nutrient Units Food Allowed Protein Fats Carbohy- drates Protein Fats Carbohy- drates Sum. Breakfast : Soup— 180 270 70 20 00 136.8 5.4 .8 .3 1.2 16.8 30.6 .5 .3 .1 .2 19.9 10.8 55.9 6.4 2,0 8.0 170.7 478.8 16.8 2.4 .3 3.7 52.6 269.3 4.4 2.6 .8 22 175.1 40.0 207.2 23.6 7.4 29.6 631.6 788.1 Potatoes 28.6 35.5 Bread, butler, etc Sum 554.6 454.4 639.4 1,948.4 Dinner : Beans 70 360 50 17.0 63.0 .6 16.8 1.0 79.2 .1 19.9 34.3 52.1 220.5 1.5 52.6 8.8 685.2 .8 175.1 126.9 187.8 905.7 Pork Tomatoes Bread, butter, etc 2.0 170.7 7.4 631.6 9.7 859.3 Sum 323.7 869.9 765.9 1,962.5 Supper : ISO 90 31.5 26.5 16.8 72.0 21.6 19.9 110.2 92.4 52.6 633.6 190.0 175.1 743.8 Sausage, bologna 1.8 170.7 6.6 631.6 289.3 859.3 Bread, butter, etc i. 255.2 998.7 638.2 1,892.4 1 ' Our table is intended to show the food values, expressed in pro- teids, fats, and carbohydrates, that are contained in the different arti- cles of food actually served out to the men during a week on board the U. S. S. Prairie. The table, incidentally, shows many points of considerable interest that are worthy of study; these I need not point out. The cardinal point brought out in the calculation is that the average daily number of nutrient units served in the form of food, per man, amounts to 5953, just twice the number required by an adult workingman of an average weight of 70 kilos. Hence our examination has shown conclusively that the new ration, as handled on board the U. S. S. Prairie, is overwhelmingly in favor of the quantitative sufficiency of the same. As regards the relative proportions existing between proteids, fats, and carbohydrates, we have seen that they must accord with cer- tain percentage requirements. A properly constructed ration must contain, according to the accepted standard, 20 per cent, in proteids, 13V,o per cent, in fats, and Q7'/,o per cent, in carbohydrates. The following "table of percentages" is intended to exhibit the results of an examination of onr ration in this respect: — J32 TEXT-BOOK OF HYGIENE. Table LI. Table of Percentages. In per cent. Differences Days of the Week Proteids Fats Carbo- hydrates 53.6 46.8 48.0 51.6 50.9 44 6 40.4 Proteids Fats Carbo- hydrates Sunday 14.8 11.4 13.0 12.6 11.3 24.6 19.6 31.6 41.8 39.0 35.8 37.8 30.8 40.0 -5.2 -8.6 -7.0 -7 4 -8.8 +4.6 - .4 +18.3 +28.5 +25 7 +22 5 +24.5 + 17.5 +26.7 —13 1 Monday -20 9 Tuesday —19 7 Wednesday Thursday -15.1 -15 8 Friday —22 1 Saturday —26 3 Average 15.3 36.7 48.3 -4.7 +23.4 -18.4 In this table the various sums of the nutrient units in proteids, fats, and carbohydrates for the three daily meals expressed in per- centages, occupy the first three columns and the plus and minus deviations from the required normal standard the last three columns. The table shows that the fats are in excess of the standard, while both the proteids and carbohydrates show marked deficiencies. The conclusion reached after an examination of the diet table given above is that, from the point of view of sufficiency, the ration exceeds the requirements, but apart from this shows certain limi- tations. WATER-SUPPLY. Although all naval vessels and nearly all the larger vessels of the mercantile marine are at present supplied with distillers for the production of drinking-water from sea-water, they cannot be said to be entirely independent of the water-supplies from natural sources on shore. Circumstances arise on every vessel, and often at that, under which the water-tanks are filled with water from shore, and naval sanitarians, therefore, cannot yet afford to disregard the general hygiene of water-supplies from all sources. Since, however, this sub- ject is treated of in another part of this work, the supply of drinking- water from sea-water, as usually done on board ships, will alone be spoken of in this connection. On board all of the vessels of the United States Navy the so- called United States Standard Evaporator is used (see Fig. 35). This evaporator is made of several sizes, the largest of which pos- sesses a productive capacity of 10,000 gallons of distilled water per diem. The general design is identical for all sizes. The apparatus WATER-SUPPLY. 333 -Distilling Plant as Installed, in Vessels of the United States Navy. consists of two parts, namely: (1) the evaporator, and (2) the dis- tiller, sometimes called the condenser. The evaporator consists of a hollow, cylindrical shell, made of steel and placed horizontally. The lower half of this cylinder is occupied by tubes running lengthwise and fixed in their positions at either end to a pair of plates which 334 TEXT-BOOK OF HYGIENE. permit of the tubes being removed for sealing in tlieir entirety. The tubes are connected with the main boilers, from which steam is run into them, generally at a pressure not exceeding forty pounds. The sea-water intended for distillation fills that portion of the lower half of the cylinder which is outside the tubes, but not quite reaching the upper level of the highest tubes. It is, indeed, the intention that the tubes shall not be entirely immersed in the salt-water, the upper level of which is, on the contrary, maintained on a level considerably below that of the tubes. The customary pressure within the shell is about ten pounds. By the use of the valves, the density of the sea-water is generally maintained at V32. The tubes of the distiller are made of tinned copper or brass; the joints are soldered. Thus we see that the evaporation of the sea-water is caused by the heat imparted to it through the steam in the pipes which the sea- water surrounds. The steam itself does not mix with the sea-water. The distiller or condenser is a cylinder, made of brass or iron in various sizes, placed vertically and fitted with straight tubes for circulating cooling water, which is made to enter at the bottom and discharge at the top. The steam to be condensed passes through the distiller in the inverse sense. On vessels which are equipped with very large plants for dis- tilling water, the apparatus is arranged somewhat differently from the above. The work of distilling is divided into two or three stages, and thus the working efficiency of the plant is thereby correspondingly increased. Under this system, steam from the boilers is used to evaporate the water in the first set of evaporators ; this evaporated steam is used to heat and evaporate the water contained in the sec- ond set of evaporators; and this in turn, is made to evaporate the water contained in a third set. The steam from the last is finally condensed to water in a distiller of the above description. This sys- tem more than doubles the actual thermal efficiency of the apparatus, but it is not installed except in very large ships, on account of the complications in mechanical fittings which it necessitates. The precautions usually observed are as follows : ( 1 ) The plant should be used only when pure sea-water is available. (3) For drinking-water, the apparatus should not be used to its full capacity, in order to reduce priming or carrying of salt-water directly over into the distillate. (3) Tests of the complete plant to be made daily to insure tightness of all the joints. (4) The water level in the evaporators is to be kept low. (5) When the ship is under way and rolling heavily, the plant must be worked at its lowest capacity. (6) WATER-SUPPLY. 335 The pressure of the cooling water in the distiller is limited by de- partmental order to thirty pounds, which is to minimize the danger of salt-water leaking into the distiller. (7) Tests of the distillate are to be made every fifteen minutes. That the water produced by this evaporator is liable to contain certain substances not expected to be present in chemically pure dis- tilled water may be seen from the adjoining table, which exhibits the results of twenty-two analyses of the water it produces, made on the U. S. S. Prairie. Table LII. Tabulated Besults of Twenty-two Analyses of Water Distilled from Salt Water by the United States Standard Evaporator. U. S. S. Prairie, Gulf of Paria, January, 1902 .2 'S o a a < 1 1 oT 1 01 .sis 'a " a ° Organic Matter, Represented in Milligrams of Oxygen per Litre 3 + + + + + + + + + + + + + + 9 + + + + + 220 30 20 10 50 20 24 130 8 12 20 20 160 30 30 20 90 12 20 32 80 32 10.0 5.0 40 6.0 11.0 16.0 70 13.0 4.0 4.0 5.5 6.0 10.0 4.5 5.0 5.0 10.0 70 8.0 6.0 80 5.0 0.0 4 2.0 5 3.5 6 1.7 7 3.6 8 2.0 9 3.2 10 6.5 13 2.0 14 30 16 3.0 17 3.0 18 4.0 20 4.5 21 5.0 22 30 23 2.5 25 2.0 26 30 27 2.0 28 120.0 30 3.0 These impurities are occasioned by defects in the water-making plant. The defects consist in slight leaks in the coils of the patent evaporator, which contain about forty-eight conical steam-joints, which are apt to work loose after long and hard usage. It may be readily seen that any leak of boiler steam through any of these joints must carry into the distiller whatever impurities it contains, such as salts of all kinds, rust, or grease. 336 TEXT-BOOK OF HYGIENE. The defect can be remedied by filling the coils of the patent evaporators with steam from the low-pressure side of the larger third evaporator. The effect of this change is to make the evaporating plant one of "double effect." The steam from the boilers enters the large evaporator-coils and evaporates salt-water. The steam from this evap- orator, before going to the distiller, is condensed in the coils of the two smaller evaporators, and only passes through the distiller to be cooled. Of course, any leak from the steam side to the water side of the small evaporators involves a slight loss of efficiency, but such a leak, no matter how great, can no longer make the distillate impure. Besides the impurities due to defects in the central distilling plant, we sometimes find that the drinking-water is contaminated from other sources. While the water taken from the distiller proves to be pure, an analysis of the water taken from any spigot may show that it is not safe to drink. Such impurities can be due only to dirty water-tanks or to faulty pipe connections. Thus, for instance, it will sometimes happen that one of the tanks is used for other pur- poses than the storage of the purest drinking-water and, before it was cleaned, drinking-water from the distiller is again run into it. Iron pipes may cause the water to be contaminated with iron rust, and lead pipes may contaminate it with small amounts of lead. All this goes to show how necessary it is that the water on board ship must be analyzed occasionally, and that the mere fact that the water is distilled must not be allowed to throw the sanitarian off his guard. With regard to the daily allowance of water per man, there are no hard-and-fast rules in the navy according to which this is regu- lated. The natural consequence of this is, as might be expected, that the supply varies directly on board the different vessels with the individual caprice or the understanding of the officer in command, being dealt out liberally on some and parsimoniously on others. While there is, generally, enough drinking water allowed, there is in all the ships too much economy shown in the supply of the men with sweet water for purposes of bathing and washing clothes. The result of this false economy is, first, that the men cannot keep their skins as clean as they ought to; and, second, for washing their clothes, the men with the cleanest habits and instincts will often get sweet water from forbidden sources and store it away in buckets which they hide in all conceivable places for future use, until they are discovered by the inspecting officer, when, of course, they not only lose the water, but are reported and punished for the mis- demeanor. When it is considered, from a sanitary point of view, that WATER-SUPPLY. 337 it is economy to be lavish with the water supply, and that especially sailors should be so trained that cleanliness of person must become for them a habit, it will at once be seen how pernicious this prac- tice is. The great necessity for a proper care of the skin becomes espe- cially apparent in the tropics, where, owing to the increased activity of the sweat-glands, skin eruptions and cutaneous abscesses are of the most frequent occurrence. Such troubles not only greatly add to the discomfort of the men, but are the efficient causes for numerous and frequent admissions to the sick-list, resulting in a loss to the service of a great many working days. That better facilities for bathing, for both officers and men, should be provided on board all the ships of the navy than are at present available is a fact upon which all officers agree. It is the duty of the sanitarian to do all in his power and urge this necessity upon the constructors of new vessels whenever he can. Since it is, of course, out of the question that a sufficient number of bath-tubs be provided for a large ship's company, shower-baths can alone be considered for the men. In some of the larger war vessels of the German navy places for showers have been provided in which fifteen men may receive a douche at one time, so that, accord- ing to the calculations of Nocht, 300 men may be served in two hours' time, at an average expenditure of 1200 gallons of water. Since, besides this, 1% gallons is the minimum allowance of water per man and per day for purposes other than drinking, we have here a basis for calculating the total water-supply needed for twenty-four hours and for the capacity of the distillers that are required to furnish the same. The first receiving ship in the United States navy on which the wash-rooms and bath-rooms for the men have received the attention at all commensurate with their importance is the recently converted ship Lancaster at the Navy Yard, League Island, Pennsylvania. This ship provides accommodations for 730 men. The wash-room is on the forward part of the spar deck, having a cubic capacity of 3584 feet, and contains 12 reversible wash-basins, all supplied with hot and cold water. The bath-room has a cubic capacity of 2040 feet and contains 8 showers, supplied with hot and cold water, the temperature of which may be regulated. This very excellent arrangement calls for the widest possible general application on all sea-going vessels of the navy. Before leaving the subject of the water-supply, a few words must be added on the scuttlc-1)utt question. The sc-uttle-butt, so-called, 22 338 Text-book of hygiene. is an iron tank filled with water and provided with one or more spigots near the bottom of it, from which the men take their drinking- water by means of a cup. This cup is suspected of being the means of the spread of infectious disease on shipboard, especially during the prevalence of epidemics like diphtheria, mumps, etc. Numerous recommendations have been made to eliminate this danger, one of the most recent ones being that of Dr. C. F. Stokes, U.S.N., who sug- gested that the cup be immersed in a solution of formaldehyde of 1 : 2500 while not in use. While this practice would undoubtedly diminish the chances of transmission of infection, it could not be said that it would altogether prevent it. When we consider that the feeling of thirst generally manifests itself in a number of men at the same time, and that often from twenty to thirty men may be observed standing in a line and wait- ing their chances to use the same cup, the paraldehyde solution would not get a chance to act on any infectious material left on the cup by a previous drinker before the next one came along. The only possible way of preventing the transmission of infection by means of the cup is to do away with the cup altogether, and serve water through a fountain so constructed that a small stream of water may be directed into the back part of the mouth without the drinker having a chance to touch the little spout with his lips. This might easily be effected by converting the scuttle-butt into a cylinder provided at intervals on its circumference with several cup-shaped depressions, from the bottom of each of which a small stream of water is forced out by gravity and which could be regulated, by a sort of spring-lock. While the rim of the depression might touch the face of the drinker, the cup-shaped depression ought to be made deep enough so that the lips could not touch the nipple of the spout. In order to catch the small amount of water that is spilt in the operation, a circular trough connected with a soil-pipe could be placed below the fountain. VENTILATION. Ventilation may be either natural or artificial. In nature, wind- currents are created by temperature differences. High temperatures over any point on the earth's surface cause the atmosphere to expand and, consequently, to rise; low temperatures have the opposite effect. A current is caused, therefore, proceeding from centres of lotv towards centres of high temperatures. We speak of ventilation as being natural, whenever air-currents are created by atmospheric tempera- ture differences alone; ventilation becomes artificial whenever these VENTILATION. 339 natural currents are assisted by other physical or mechanical agencies. The ventilation which is constantly taking place in our houses and dwellings may be taken as an example of natural ventilation. The porous nature of the building materials, the winds, the differences between the temperatures of the inside and outside air, are the effi- cient causes of this ventilation. In an experiment by von Petten- kofer it was found that in a room of 75 cubic metres capacity, one complete change of air occurred in one hour through a difference in temperature between inside and outside of 20° C. Under ordinary conditions, the cold air will enter below and the warmer air will make its escape from the top of the building. Such natural ventilation, it will readily be seen, could never be expected to occur in a ship. A ship's bottom and sides are practically made both air- and water- tight. Hence, whatever fresh air is ex- pected to get into a vessel must come from the top side and be made to find its way to all the various parts below before it can be said that the ship is at all ventilated. Since, moreover, a ship is divided into many separate compartments not in direct communication with the general ship's spaces, the air (the deeper it descends the warmer it must get) will be returned before it reaches the deepest parts of the ship; it thus must happen that a large portion of the inside of a ship will never be ventilated by natural means at all. This is also the reason why the air in ships is always found to be growing more and more contaminated, the deeper down towards the bottom it is examined. We may now also understand why it is that, in order to ventilate all ships effectively, we must resort to ventilation by arti- ficial means. Since the most economical, thorough, and efficient ventilation is that ventilation which aids the natural currents existing inside of a vessel, all artificial systems should be so arranged as to meet this most important requirement. In a steamer, for instance, of modern construction, such as a cruiser or battleship, with enormous fires and engine-rooms, large steam-pipes, and a number of auxiliary engines situated, for the most part, in the middle of the ship's space and radiating considerable amounts of heat, air-currents from all parts of a vessel would, under average conditions, move in their direction; that is, from the colder, loioer, and peripheral portions toward the warmer, higher, and central parts of the compartments. All supply shafts in a ship, in accordance with this principle, should, therefore, be made to reach as nearly as possible the bottom and the most periph- eral parts of any compartment to be ventilated, before being allowed 340 TEXT-BOOK OF HYGIENE. to set free the imprisoned air which they brought down from above and which is intended for the ventilation of any particular compart- ment; while the outlets for the foul air should, for the same reasons, be nearest the middle line and open flush with the deck ceiling. It is in this manner only that any compartment can be most efficiently, as well as most economically, ventilated. Different Methods of Ventilation. — A ship is said to be ventilated either by the vacuum or the plenum method, according as the greater motive power is in the discharge or in the supply part of the system. The power may be solely in either one or the other of the two parts, or it may be shared between them. Its predominance in the one or the other determines the "^vacuum" or the "plenum" character of the system. (Woodbridge.) Vacuum Method. — This method causes a current of air in an enclosure by a partial vacuum within it. Into such an enclosure the air then flows through every available channel, both provided and ac- cidental. From whatever points, therefore, the pressure may be greater than in the enclosure ventilated by the vacuum method, from thence it will move toward that enclosure. Each space, therefore, is more or less at the mercy of its surroundings and of conditions be- yond the control of its occupants. The vacuum method of ventila- tion on shipboard puts the breather at the point of discharge of foul air, and sends into the living spaces specimens of air from every part, near or remote, whether filled with pure or foul air. Plenum Method. — This method, by putting each compartment under slight pressure, prevents leakage of air from adjoining com- partments. It tends to accelerate the escape of foul air through natural outlets, and gives the occupants control over the source and the velocity of their air-supply. The method puts the breather at the point of supply and, consequently, in a position to breathe the best of air. It is recommended as the best by Eubner, Kirchner, Karl Schmidt, Notter, Harrington, Woodbridge, and Munson. It will supply a steady current of fresh air to all the compartments in a ship alike, and by tending to produce even conditions of temperature and pressure it will prevent untoward currents and countercurrents between the different enclosures, in spite of free communication exist- ing between them. The ideal aim of any ventilating system, in theory at least, would be the getting rid of foul air in an enclosure and the replacing of this by fresh air, without the two becoming mixed. In practice, however, and as Rubner has long since pointed out, we are obliged VENTILATION. 34 j^ to take our air for inspiration out of the same reservoir into which we send our expiratory air. It would, therefore, seem impossible for any ventilating system to so sharply separate the good air from the foul air as to prevent the two from becoming mixed to a certain extent. All artificial ventilation must, accordingly, proceed after the manner of a process of dilution, and be so arranged as to keep the enclosed air from reaching a composition very much different from outside air. This is more especially the case on board all ships, naval as well as mercantile, under just such conditions when ventilation comes into play most beneficiently, namely, during maneuvres and in bad weather. It is, consequently, far more important to provide means for an abundant supply of fresh air in the ventilating of sliips than it is to provide those for getting rid of foul air. The more general introduction of the plenum system in ships' ventilation is, therefore, most desirable, as well as in the most perfect keeping with the re- quirements. Since the details of ship ventilation and the principles of the examination of air, as well as the sources of its contamination, have been very recently discussed by Beyer and Plumert, we may conclude this chapter by giving a description of the type plans for the ventila- tion of some of our newest designs of battleships. But before giving this description, mention must be made of an important discovery as regards the composition of the air enclosed in the double bottoms, by Dr. C. M. Belli. It had been known for a long time that the air in these places became after a time so bad that it was dangerous to enter them, without testing the air first by means of a candle, and whenever that went out the air in them was renewed with a portable ventilator. It was always believed that the cause of the asphyxia was an accumulation of CO2 in these places. Belli, on the contrary, found, by a number of eudiometric analyses of specimens of air collected from these double bottoms, that while the CO2 was present in the proportion of 1.4 per cent., the oxygen had decreased from 20 to 3 per cent. Hence it would seem that all previous cases of asphyxia reported as occurring in the double bot- toms were due to a want of oxygen rather than to the presence of too much COo. Further experiments showed that the oxygen was indeed absorbed by the linseed oil and minium, a mixture with which the iron sides and bottoms of these compartments are thickly coated. It would not be surprising if it should be found, on further experi- mentation, that a want of oxygen more than the accumulation of CO2 was, after all, the real cause of the insufferable condition of the 342 TEXT-BOOK OF HYGIENE. atmosphere of places in ships other than the double bottoms. Ex- perimental inquiries alone can establish the truth of this supposition. The Ventilating System of the Idaho and Mississippi. — The Idaho and Mississippi are sister ships and classified as first-class sea- going and coast-line battleships. Their length and breadth, at load water-line, are 375 and 77 feet respectively. The displacement is 13,000 tons. They have a bridge deck, upper deck, main deck, berth or protective deck, and an upper and lower platform. They will each carry a complement of not less than 720 officers and men. According to the designs of these vessels, it is the intention to provide artificial ventilation for all quarters, living spaces, passages, store-rooms, and magazines below the main deck, as well as for the air-spaces over the boiler- and engine- rooms and around magazines; for the water-closets and similar enclosures above the main deck and for turrets. The hull-ventilating arrangements for these vessels were designed in accordance with what are considered the latest approved methods, the efficiency of which was demonstrated by numerous ex- periments. The system has been so subdivided as to render unneces- sary the piercing of any of the principal water-tight bulkheads with the ducts except M^here shown in the type plans (Figs. 36, 37, and 38). These vessels, having a system of hatches and skylights opening through the various decks in nearly vertical lines, in a number of the principal subdivisions, it was not considered necessary to install both "supply" and "exhaust" systems for any spaces except the dynamo- rooms. The main hull ventilation will therefore, be fitted as shown in the type plans (see Figs. 36, 37, and 38) with the single-way sj^s- tem. The water-closets, etc., on the main deck will be ventilated on the "exhaust" system and the remaining compartments, except the dynamo-rooms, on the "supply" or "plenum" system only. The ducts are designed to pass the number of cubic feet of air per minute through each terminal as may be seen on the type plans (see Figs. 36, 37, and 38), or to equal the total number of cubic feet per minute for each compartment as marked on the plans, with the fans running at a speed corresponding to 1 ounce pressure with restricted delivery. This will allow the air to be renewed in the vari- ous spaces approximately as follows : — 1. Officers' quarters and crew space, berth deck outside of trans- verse armor, in about twelve minutes, or four times in one hour. 2. Officers' quarters, crew space, and general work-shop, within transverse armor, in about five minutes, or twelve times in an hour. 3. Water-closets and crew's head in about five minutes. S^Crto^ A A 15 ti M 3S ar 3S 33 31 as tj as 13 21 o T S 3 B e/PT/>/rks V/l l/^Mr/i/trort &f>SH fteUS c.r. coat. T/rutf/rS J^/^l/^ 0£Cff Fig. 4 1 ,0^£-/?/9T/A/C P00i^ ^ .COft^S £i/9fe:A/^jV/fY ot" \'r*])t ihi t ion on llu' Mnlio ;inrl Mississippi. VENTILATION. 843 4. Store-rooms in general, magazines, and passages in about eight minutes. 5. Engine-rooms and steering compartments in about two minutes. 6. Evaporator-rooms in about two and a half minutes. 7. Air-space over boilers in about one minute. 8. Dynamo-rooms in about three-quarters of a minute. Twenty-three fans are required for the ventilating system of these vessels, all to be electrically driven and to be located as indicated on the plans (see Figs. 36, 37, and 38). Pan No. 1.— To exhaust from water-closets, etc., on the main deck forward of bulkhead No. 15, and also from sick-bay water- closet and contagious ward. Fans Nos. 2 and 3.— To exhaust from firemen's wash-rooms, evaporator-rooms, and passages on berth deck, between bulkheads' 351/2 and 57. The discharges from these fans to be used for ventilat- ing the air-spaces over boilers. Fan No. 4.— To exhaust from officers' water-closets on main deck between bulkheads 521/2 and 59. The discharge to be used to assist exhaust from after dynamo-room. Fans Nos. 5 and 6.— To supply fresh air to officers' quarters and to compartments above protective deck abaft bulkhead 57. Fans Nos. 7 and 8.— To supply fresh air to magazines and store- rooms below protective deck, between bulkheads Nos. 671/2 and 79, and also to ammunition passages aft of frame 48. Fan No. 9.— To supply fresh air to sick-bay, operating room, dispensary, store-rooms, and passages above protective deck and for- ward of bulkhead No. 19 ; and also to all compartments below pro- tective deck and forward of bulkhead No. 19, except chain lockers and trimming tanks. Fans Nos. 10 and 11.— To supply fresh air to magazine and store-rooms below protective deck, between bulkheads Nos. 19 and 30. Fans Nos. 12 and 13.— To supply fresh air to compartments on berth deck between bulkheads Nos. 19 and 351/2 and to ammunition passages between frames 30 and 48 ; also to communication room, and forward distribution board-room. Fans Nos. 14 and 15.— To supply fresh air to forward dynamo- room. Fans Nos. 16 and 17.— To exiiaust from compartment between bulkheads Nos. 30 and 35% on berth deck, the discharge to be used to assist exhaust from the forward dynamo-room. 344 TEXT-BOOK OF HYGIENE. Fans ISTos. 18 and 19. — To supply fresh air to after dynamo-room and after distribution board-room. Fans No. 20 and 21. — To supply fresh air to engine-rooms. Fans Nos. 22 and 23. — To supply fresh air to steering com- partments and store-rooms on upper platform aft of bulkhead No. 79; also to hold between bulkheads Nos. 79 and 83. It is the intention to supply all these fans with power sufficient to run them continuously, when necessary, at a speed required to produce IV2 ounces pressure, under conditions of shop test, but to have such variation in speed as will permit them to run under or- dinary service conditions at the speed required to produce 1 ounce pressure. In designing the ventilating system for these ships, great care has been taken to allow for the loss of capacity due to frictional resist- ance, and special attention was paid to the bends in the ducts, none of which are to be made with a radius of throat smaller than the diameter of the duct. It was found by experiment that the loss due to friction in a twent3'-foot length of straight duct is about 10 per cent., and that the loss in a ninety-degree bend, when proj)erly con- structed, with a radius of throat not less than the diameter of the duct, is about the same amount. If the bends are made with a sharp joint or with a smaller radius, the loss will be greater. The ducts are to be made smooth inside and free from all internal projecting lips and other obstructions. The branches and terminals will be m:ide to leave the main duct at an angle of not more than 15 degrees to the direction of the air-current and be curved to the desired direction by a very easy bend. All magazine terminals will be fitted with automatic ball attachment and cage, protected by portable one-half inch wire mesh covering the same. McCreery or other equally effective adjust- able elbows, fitted with butterfly dampers, will be used for terminals in all quarters, living spaces, and elsewhere, as shown in type plans (Figs. 36, 37, and 38). All the openings of these elbows are to be fitted with portable wire mesh, not less than one-half inch. All other terminals to be stationary and, except those ending in valves, to be fitted with plain butterfly dampers and portable iron mesh, not less than one-quarter inch. All terminals to be bell-mouthed to twice their area, where fitted with wire mesh. Table LIII. Tabulated Index to Artificial Ventilation Arrangevients of ^'^ Idaho ^^ and ' ' Mississippi, ' ' Shown in Part in Figs 36, 37, and 38. "3 FAN SPACE (^ .2 s> Ph s .2 3 a a i .o t, g H^S 3 0).= ^ V^ < Exhaust Crew's head, over water-closets 6 800 No. 1 — Main deck '* " urinals 6 450 Capacity, 1725 cubic feet per " " wash-basins 6 300 minute Contagious ward 6 100 1 oz. pressure Sick bay bath-room 6 75 Exhaust Exhaust from firemen's wash-room No. 2 — Main deck and supply to air-space over boilers 1 3070 Capacity, 3070 cubic feet Exhaust Exhaust from firemen's wash-room 1 1270 No. 3 — Main deck " " dynamo-room and Capacity, 3070 cubic feet supply to air-space over boilers 1 1800 Exhaust From officers' bath and water-closet 4 943 No. 4— Upper deck space Capacity, 943 cubic feet Supply Captain's after-cabin 10 160 No. 5 — Main deck " dining-cabin 10 200 Capacity, 4640 cubic feet ' ' state-room ' ' bath-room 10 10 125 75 No. 6— " office 10 100 4640 cubic feet " pantry 10 50 Ward-room Dining-room 10 400 " state-rooms behind armor 4 100 " state-rooms not behind armor 10 75 ' ' pantry 4 150 Junior and warrant officers' mess- rooms (each) 4 400 Junior and warrant-officers' state- Y fl25 1150 rooms (each) Junior and warrant-officers' pan- tries (each) 4 125 Country in vicinity of officers' quarters 4 2100 Supply Magazines on upper platform 8 2200 No. 7— " " lower 8 1650 Capacity, 4640 cubic feet in hold 8 350 Passages and haudling-rooms 8 3150 No. 8— Storerooms 8 1620 Capacity, 4640 cubic feet Supply Sick Bay n 600 No. 9— Berth deck Operating-room ^ 125 Capjicity, 5320 cubic feet Dispensary n 75 Lamp-room 8 125 Paints and oils 8 200 Torpedo manipulating-room 8 . 1600 Fresh water tank space 8 200 (845) Table LIII. — {Continued.) Tabulated Index to Artificial Ventilation Arrangemeiits of "Idaho'' and ' ^Mississippi, ' ' Shoion in Part in Figs. 36, 37, and 38. FAN SPACE g i a Cubic Feet Per Minute About Supply No. 10— Capacity, 3690 cubic feet No. 11— Capacity, 3690 cubic feet Magazines on upper platform " on lower "' in hold Passages and handling-room Store-rooms 8 ' 8 8 8 8 1850 1720 1080 1200 940 Supply No. 12— Berth deck Capacity, 3070 cubic feet No. 13— Capacity, 3070 cubic feet Bakery Workshop Chief petty officers' quarters " " " wash-room Crew space, berth deck Ice machine room Ammunition passages Passages Communication-room Laundry 8 5 5 5 5 5 8 8 8 5 150 330 500 90 400 100 2170 1300 80 300 Supply No. 14— Berth deck Capacity, 5320 cubic feet No. 15— Capacity, 5320 cubic feet To forward dynamo-room f 10,640 Exhaust No. 16— Berth Deck Capacity, 943 cubic feet No. 17— Capacity, 943 cubic feet Crew space 8 1886 Supply No. IS^Berth deck Capacity, 5320 cubic feet No. 19— Capacity, 5320 cubic feet To after dynamo-room i 10,640 Supply No. 20— Capacity, 10,800 cubic feet No. 21— Capacity, 10,800 cubic feet To engine-rooms 2 21,600 Supply No. 22— Capacity, 1190 cubic feet No 23— Capacity, 1190 cubic feet To steering gear Storerooms 2 8 1615 765 Supply Two in each boiler room each 15,625 cubic feet. Each boiler-room 31,250 (346) QUESTIONS TO CHAPTER XI. MARINE HYGIENE. Define marine hygiene. In what respects does it differ from naval hygiene? What are the causes of the decrease in morbidity and mortality in modern ships as contrasted with those in the old ships? What is the mor- tality rate among seafaring people in recent times? Name some of the most prevalent diseases. On what system is a ship drained? What are the separate functions of the main, secondary and auxiliary drains, respectively? How is the bilge formed? Where is the bilge-room located? What changes in the construction of ships have affected the location of the bilge space and how? How is the composition of the bilge affected by these changes ? What is a bilge-well ? What is a Macomb strainer and its object? What is the chemical and bacteriological composition of bilge-water? How many distinct types of bilge-water may be distinguished on board a man-of-war? What are the distinguishing characters in each? What are the chances of bacterial infection from infected bilge-waters? What are the different decks on a merchant ship called? Name the different decks on a battle-ship? What is the location of the engine- and fire- room? What and where are the double bottoms? Describe the location of the men's quarters. What is the usual cubic air-space per man allowed, ( 1 ) on merchant ships, and (2) on war-vessels? Wliat is the effect of dampness on shipboard on the health of the men? How is the bilge-room cleaned? Name some of the special precautions to be observed in the disinfection of ships in special cases. Enumerate the most necessary disinfecting agents on board, and define the uses of each. Describe in detail the process of Nocht and Giemsa for the extermination of rats. What is meant by the term "ration" and what is the difference between it and an ordinary "bill-of-fare"? What are the food values per gram of proteids, fats, and carbohydrates respectively? What are the relative pro- portions in proteids, fats, and carbohydrates to which the composition of a complete meal should correspond? Describe the U. S. standard evaporator. What may be the sources of contamination in the water distilled by this machine? What are the sub- stances occasionally found in such water? What is a reasonable allowance per man and per day on board ship? What are the dangers of the scuttle- butt cup and how are they to be prevented? Give an example of natural ventilation. What is the object of artificial ventilation, and how must it be arranged to be most effective as well as economical? What are the different methods of artificial ventilation, and what does each method do? WTiich of the two is best adapted to ships? De- scribe the main features of the ventilating system of the Idaho and Missis- sippi. (347) CHAPTER XII. PRISON HYQIENE. Although the frightful mortality which formerly seemed a necessary accompaniment of the life of the convict has in the past half-century markedly diminished, the death-rate among prisoners is still very greatly in excess of that of persons of the same age in, a state of liberty. The observations and labors of John Howard, the self-sacrificing philanthropist, and of Elizabeth Fry, directed the attention of legisla- tors to the necessity of reform in the conduct of prisons and the treat- ment of prisoners. As a consequence of the labors of these reformers, the principles of prison discipline have been more fully developed during the past forty years by students of social science everywhere, and certain propositions have been formulated, which govern, to a greater or less degree, legislation upon this subject. These propo- sitions are, briefly, as follow: — Prisoners must be properly classified according to the nature of their crime and the duration of imprisonment. The two sexes must be strictly separated, and no opportunity given for intermingling while in the prison. Female prisoners should have female attendants exclusively. Male watchmen or other attendants should not be allowed in the fe- male department of a prison. All prisoners must l)e kept employed at some manual labor, not necessarily for profit, but as an agency in the moral reformation of the convict. Punishments for infractions of discipline must not be excessive. Efforts should be constantly made tending to the reclamation of criminals from their life of sin and crime. Due care must be taken by the State to preserve the health and life of the prisoner whom the State has deprived of liberty and the opportunity of taking care of himself. A proper classification of prisoners, according to the degree of their criminality, the nature of the crime of which they have been convicted, or the length of time for which they have been sentenced, is now insisted upon by all students of prison discipline. As this sub- (348) PRISON HYGIENE. 349 jeet more nearly concerns the social or legal relations of prisoners rather than their sanitary interests, it is here passed over with a mere mention. The separation of the sexes, necessity of female attendants on prisoners of the same sex, employment of prisoners, and moral re-? formation of criminals likewise belong especially to the social aspects of the question, and can find no discussion in this place. Eegarding the remaining proposition, however, that which de- mands that the State shall exercise due care over the prisoner's health, it comprises a question that demands consideration in a text-book of hygiene. There is now a general concurrence of opinion that the State, in depriving any person of liberty, has no right to subject the individual suffering such deprivation to any danger of disease or death. In other words, the State has no right to abbreviate the life of the convict sentenced to prison. This proposition requires that the State see to it that the prisoner is well fed, well clothed, and well housed ; that he shall be well cared for when sick, and that when his term of imprison- ment expires he shall be set at liberty, with only such effect upon his normal expectation of life as would result from the ordinary wear and tear of life upon his health. It must be confessed, however, that the State is very far short of attaining this object. The mortality of convicts, even in the best- regulated prisons, where especial attention is paid to the sanitary re- quirements of such buildings, is three times as great as among work- men in mines, confessedly one of the most dangerous occupations. If insurance companies desired to insure the lives of prisoners, the com- panies would be obliged, in order to secure themselves against loss, to make the premium equivalent to an advance in age of twenty years. This means that a free person has as long expectation of life at 40 years as a prisoner has at 20. Attention is again called to the fact that the conditions in the most favorably situated and liberally managed prisons only are here considered. What the results are in other institutions, less favorably constructed and managed, will be apparent from the following brief statement : Mr. George W. Cable^ has shown that in some of the prisons in the Southern States, under the vicious lease system, the mortality is eight to ten times greater than in properly constructed and managed prisons elsewhere. In Louisiana, for example, 14 per cent, of all the prisoners died in 1881; '■ Century Magazine, February, 1884. 350 TEXT-BOOK OF HYGIENE. and in the convict wood-cutting camps of the State of Texas one-half of the average number so employed during 1879 and 1880 died. The mortality of prisoners is greatest in the second, third, and fourth year of their confinement. In Millbank Prison, in England, the death-rate per 1000 was 3.05 in the first year, 35.64 in the sec- ond, 52.26 in the third, 57.13 in the fourth, and 44.17 in the fifth years of imprisonment. The diseases most frequent among prisoners are pulmonary phthisis and diseases of inanition, manifested by general dropsy. Consumption furnishes from 40 to 80 per cent, of all deaths. When prisoners are attacked b)^ acute febrile or epidemic diseases (small-pox, cholera, dysentery), the mortality is much higher than among per- sons in a state of liberty. This fatality is due to an anemic or cachectic condition, which has been called "the prison cachexia," — a depravement of constitution which yields readily to the invasion of acute diseases. Eecently a number of model prisons have introduced modem sanatorium treatment of consumptive prisoners. Prisons should be built upon a healthy site, be properly heated and ventilated, have an abundant water-supply, and be supplied with facilities for a prompt and thorough removal of sewage. Baths and lavatories should be conveniently arranged in order that thorough cleanliness can be enforced. The problem of feeding prisoners requires careful study. The food should not only be sufficient in quantity and of good quality, but it should be well cooked, and the bill-of-fare varied often in order to avoid creating a disgust by an everlasting sameness. Prisoners often suffer from nausea and other digestive derangements, brought on solely by the monotonous character of the daily food. In workshops and sleeping-rooms, dormitories or cells, the cubic air-space allowed to each inmate should not be less than 17 cubic metres, with proper provision for ventilation. The use of dark or damp cells as places of confinement is a relic of the barbarism in the treatment of convicts against which John Howard raised his voice so effectively in the last century. An abundance of sun-light should be admitted into every room in which a human being is confined. An important hygienic measure is daily exercise in the open air. It should be regularly enforced, and its modes frequently varied in order that it may not degenerate into a mere perfunctory performance. Punishment for infractions of the prison discipline should be in- flicted without manifestation of passion, and only under the im- mediate direction of some official responsible to the State. It is ques- PRISON HYGIENE. 351 tionable whether physical punishments, such as whipping, tricing up by the thumbs with the toes just touching the floor, bucking and gagging, and similar barbarities should be permitted under any con- ditions. The permission to exercise such power is extremely liable to be abused by officials. The system of leasing out prisoners to pri- vate parties which prevails in some of the southern United States is vicious in the extreme, because it places the convict under the con- trol of persons not responsible to the State, and, in the majority of instances, morally unfitted to wield the power of inflicting punish- ment. QUESTIONS TO CHAPTER XII. PRISON HYGIENE. How does the mortality of those who are in prison compare with those of the same age who are free? What philanthropists called early attention to the abuses of prisons and prisoners? What fundamental propositions now practically govern prison legislation? Why must the State exercise due care over the prisoner's health? What must the State do to attain this object? Does it succeed in doing it? How does the excessive mortality compare with that of dangerous occupations? How does the expectation of life compare with that of those outside of prison? What is the mortality where the lease- system obtains? When is the mortality among prisoners greatest? What diseases are most frequent among prisoners? What is the effect of acute febrile or epidemic diseases upon prisoners? To what is this due? What principles should be observed in prison construction? What points should be particularly observed regarding the food of prisoners? How much air-space should be allotted to each prisoner, whether in workshops or cells? What precautions should be taken against dampness and absence of simlight? What is another important measure that should be enforced daily? How should all punishments be inflicted, and what ones should be prohibited? What can be said of the lease system? (352) CHAPTER Xni. PERSONAL HYGIENE. All sanitary and hygienic precautions relate more or less directly to the person, but those princip'es which concern most intimately the habits and body of the individual, rather than his surroundings and environment, are conveniently grouped in a class denominated Personal Hygiene. EXERCISE AND TRAINING. Exercise is the performance of work, or overcoming resistance. To be efficacious from a hygienic standpoint, it must affect not only all the voluntary muscles, but every organ and tissue of the body. The healthy functions of the bodily organs can only be main- tained by more or less constant use. A muscle or other organ that is unused soon wastes away, or becomes valueless' to its possessor. On the other hand, trained use of the various organs makes them more effective for the performance of their functions. Thus, by practice, the eye can be trained to sharper vision,- the ear to distinguish slight shades of sound, the voice to express varying emotions, -the tactile sense to accurately appreciate the most minute variations of surface and temperature, and the hand to greater steadiness or the perform- ance of diihcult and complex feats. The effectiveness of other organs, muscles, or groups of muscles can also be increased by systematic training, as is seen in the athlete and gymnast. When a muscle contracts, the flow of blood through it is in- creased. Hence, contraction of a muscle, which consumes or con- verts stored-up energy, at the same time draws upon the circulation for a new supply of food-material to replace that consumed. The activity of the circulation through a muscle in action results in in- creased nutrition and growth of the muscle. During muscular action the activity of the respiratory process is increased. A larger quantity of air is taken into the lungs, more oxygen is absorl)ed l:)y the blood, and an increased elimination of car- bon dioxide takes place. The experiments of Pettenkofer and Voit show that, while in a state of rest the average absorption of oxygen in twelve hours amounted to 708.9 grammes, during work the amount renr-hf'fl 954.5 grammes. For the same period the elimination of car- 23 (353) 354 TEXT-BOOK OF HYGIENE. bonic dioxide was: during rest, 911.5 grammes; during work. 1384.2 grammes. Upon the circulation muscular exercise likewise exerts a manifest influence. The action of the heart is increased both in force and fre- quenc}^, the arteries dilate, and the blood is sent coursing through the s^'stem more rapidly than when the body is at rest. Cutaneous transpiration is also promoted by muscular exercise. In this way some of the effete matters in the system are removed, being held in solution and carried through the skin in the per'^piration, helping out the kidneys in the performance of their function, and saving them from undue wear and tear. There can be no question that systematic training of the mus- cles has a favorable influence upon health and longevity. Persons who are actively engaged in physical labor, other things being equal, are healthier, happier, and live longer than those whose occupation makes slight demands upon their muscular system. In default of an active occupation the latter class is forced, if good health is de- sired, to adopt some form of exercise which will call the muscles into activity. The principal methods of physical training are walking or running, rowing, swimming, out-of-door games, such as golf, tennis, foot-ball, and base-ball, and the various in-door gymnastic exercises. Eapid walking or running is one of the best methods of physical exer- cise, for, not only are the muscles of the legs and thighs developed, but the capacity of the chest is increased — one of the principal objects of physical training. By combining walking with some form of in-door g}Tnnastics, such as practice with dumb-bells, Indian clubs, rowing-machines, or pulley-weights, nearly all the good effects of the most elaborate system of training can be obtained. For the gymnastic exercises various forms of useful labor may be substituted with advantage, such as wood-chopping or sawing, or moderate work at any physical labor. The scheme of studies in our public-school system should include physical training for both sexes. This is a question not merely of individual, but of national importance. Weak and unhealthy chil- dren are not likely to grow up into strong and healthy men and women; and the latter are necessary for the perpetuity of the nation. The time seems to have arrived when physical education should no longer be looked upon as a whim of unpractical enthusiasts and hobby- riders, bvit as an indispensable element in every school curriculum. There is a tendency among instructors in physical training to EXERCISE AND TRAINING. 855 make their systems too complicated, or dependent upon expensive or cumbersome apparatus. This is to be deprecated. All the muscles of the body can be called into action by very simple exercises, easily learned and readily carried out. An important preliminary to all methods of training is a thorough physical examination of the pupil by a competent physician, in or- der to determine whether certain exercises are allowable. For ex- ample, in all organic heart affections exercises of a violent character must be interdicted. A boy or man with valvular disease of the heart cannot run, row, or swim with safety. The organ is easily overtasked in this condition and liable to fail in its function. One of the simplest and best methods to cause the pupil to as- sume a correct position of the body, and to acquire ease and grace in his movements, is to teach him the "setting-up," as practiced in the United States arniy.^ In walking, a free, swinging step should be acquired, with the head erect, shoulders thrown back, and the chest well to the front, the whole body from the hips upward inclining slightly forward. The clothing should be loose around the upper part of the body, in order not to interfere with the freest expansion of the chest, and to give the lungs and heart ample room for movement. Even in-door gymnastic exercises alone, when practiced under intelligent provision, will ac- complish very favorable results, as shown by the following table : — Table LIV. Showing Average State of Development on Admission to Gymnasium ; Average State of Growth and Development after Six Months' Practicing Two Hours a Week, and Average Increase During that Time. {Bowdoin College Gymnasium, under Dr. D. A. Sargent. Two Hundred Students from the Classes of 1873 to 1877, inclusive. Average Age, 18.3 Tears. )2 Height Weight Chest (inflated I . Chest (contracted) Forearm Upper arm (flexed) Shoulders (width) Hips- Thigh Calf On Admission. 170.0 cm. 60.7 kg. 87-5 cm. 80.6 " 25.0 " 27.5 " 38.7 " 78.7 " 48.7 " 31.2 " After Six Months' Practice. 170.6 cm. 61.6 kg. 91.8 cm. 82.4 26.8 29.0 40.5 84.4 52.6 38.0 Average Increase. 0.6 cm. 900.0 gms. 4.3 cm. 1.8 " 1.8 " 1.5 " 1.8 " 5.7 " 3.9 " 1.8 " ' Upton's Infantry Tactics. School of the Soldier, Lesson I. '■'Apparatus used: Wcif^lits, 4500 to 6750 grammes; Dumb-bells, 1125 grammes; Indian clubs, 1575 grammes; Pulleys. 356 TEXT-BOOK OF HYGIENE. The table on the following page shows the average rate of in- crease in development in a two years' and a four years' class in Am- herst College, and also the percentage of increase in one four years' class from entrance to graduation. The interesting fact has been brought out by Mr. Delabarre that tobacco-smoking has a decidedly deleterious effect upon the rate and percentage of physical develop- ment in students. In weight non-smokers gained 24 per cent, over smokers; in height, 37 per cent., and in chest-girth, 42 per cent. However necessary for the preservation of health physical exer- cise may be, overexertion should be carefully avoided. Overstrain and hypertrophy of the heart are often the results of excessive exer- tion. Dr. Da Costa has described a form of "irritable" and weak heart occurring especially among soldiers, which he has clearly traced to overexertion. Severe labor and violent athletic exercises have been followed by like serious results. Long-distance pedestrian- ism has furnished, within recent years, quite a number of individuals who were broken down in health by the excessive strain on the physi- cal organization involved. Cardiac strain is not infrequent among this class. Spasm, paralysis, or atrophy of muscles sometimes results, when these are exhausted by uninterrupted or excessive exercise. This effect is shown by writers' and telegraphers' cramp, and similar affec- tions. For these reasons it is important that exercise both for health and for actual work should be so regulated as to conduce to the indi- vidual's benefit, and not to his detriment. As to the amount of exercise required. Dr. Egbert says (Hygiene and Sanitation, p. 283) : "It is hard to determii^e how much exercise any given person ought to take, as the personal equation varies so much. The average healthy man should probably do work equivalent to 150 foot-tons daily. The work of walking on a level at the rate of three miles per hour is said to be equal to that of raising one- twentieth of the body-weiglit through the distance walked. Accord- ing to this, a man of 150 pounds in walking one mile does work equal to 17.67 foot-tons, and his total daily physical labor should be equiva- lent to walking about nine miles at the above rate to get the proper amount of daily exercise. This seems like an excessive amount, but if the actual physical work of one's customary vocation be taken from this, it will not leave so very much for the daily health-task; and while the natural disinclination of many to exercise grows stronger by indulgence, and while urgent reminders are wanting and the evils arising from the neglect, iabuse, or misuse of exercise are not so very immediate or apparent, the latter are still certain to result, and are not at all consistent with good and perfect health." BATHS AND BATHING. 357 Table LV. Showing Physical Gains of Students in Amherst College During a Part and During the Wiole of the College Course. {Prof. E. Hitchcock, Dr. H. H. Seelye, and Mr. F. A. Delabarre. ) Weight Height fcjternum ....'.. Navel Pubes Knee Sitting Girth, Head Neck Chest repose .... Chest full Belly Hips Right th^gh . . . . Left thigh Right knee Left knee Right calf Left calf Right instep . . . . Left instep Upper right arm . . U. R. A. contracted Upper left arm . . Right elbow . . . . Left elbow . .*. . . Right forearm . . . Left forearm . . . . Right wrist . . . . Left wrist Breadth, Head Neck Shoulders Nipples Waist Hips Right-shoulder elbow . Left-shoulder elbow . . Right elbow-t'p . . . . Left elbow-tip Length, Right foot . . Left foot Stretch of arms . . . . Horizontal length . . . Strength Lungs Back Chest dip Chest pull up . . . Legs Right forearm . . . Left forearm . . . Capacity of lungs . . . Gain of Two Years' Class. Metric. .2.6 .11 .3 .4 .8 .4 .14 .5 .10 .14 .9 .10 .15 .19 .13 .4 .3 .9 .11 .2 .2 .13 .11 .14 .6 .6 .4 .3 .1 .2 .1 .2 .11 .7 .2 .2 .3 .2 .2 .2 .2 .1 .19 .14 ».73 a. 30 .2.8 i>2.6 bl.l a, .33 a. 5 a. 5 cl.2 English. db.72 .43 .11 .15 .31 .15 .55 .19 .39 .55 .35 .39 .59 .74 .51 .15 .11 .,35 .43 .07 .07 .51 .43 .55 .23 .23 .15 .11 .03 .07 .03 .07 .43 .27 .07 .07 .11 .07 .07 .07 .07 .03 .74 .55 d 160.9 d.66 d61.7 a 72.7 dU dll.O e73.2 Gain of Four Years' Class. Metric. 5.40 .16 .11 .9 .5 .12 .18 .7 .14 .41 .34 .41 .36 .24 .25 .6 .7 .13 .10 .8 .9 .13 .17 .16 .6 .5 .5 .6 .2 .3 .3 .4 .19 .13 .9 .11 .4 .4 .10 .6 .5 .4 .24 .20 .82 .64 .28 2.3 1.2 .37 .7 .5 3.6 English. 11.8 .63 .43 .35 .19 .47 .7 .27 .55 1.61 1.33 1.61 1.41 .94 .98 .23 .27 .51 .39 .31 .35 .51 .66 .62 .23 .19 .19 .23 .07 11 .11 .15 .74 .51 .35 .43 .15 .15 .39 .23 .19 .15 .94 .78 180.8 1.41 61.7 81.5 15.4 11.0 219.6 Per Cent. of Increase in Class of '91. 8.9 0.6 0.7 1.2 :s.3 0.4 1.3 0.5 2.5 3.0 1.0 4.1 2.4 3.0 3.1 0.8 1.1 2.8 2.3 0.8 0.8 6.3 6.4 7.8 3.5 3.5 3.3 3.1 0.0 06 0.6 1.8 3.6 6.4 3.4 1.8 1.1 0.8 1.5 1.5 1.1 1.1 1.3 0.6 26.9 27.8 24.0 38.0 20.5 26.0 23.7 16.6 4.0 Weij 8.1 ;ht, Height, 2.72 Giith. 2.72 Breadth, 2.93 Strength, 25.31 Capacity, 4.00 A total average gain of 5.87 per cent. a — Kilos, b — Units. c— Litres, d— Pounds, e— Cubic inches. All others. Millimetres, and Inches and Tenths. BATHS AND BATHING. T]](i most iiriportaiit sanitary object of bathing is cleanliness. A secondary object of the bath is to stimulate the functions of the skin, 358 TEXT-BOOK OF HYGIENE, and to produce a general feeling of exhilaration of the bod3^ Baths are used of various temperatures. A cold bath has a temperature of from 4° to 24° C. (40° to 75° F.) ; a tepid bath from 24° to 30° C. (75° to 85° F.) ; a warm bath from 30° to 38° C. (85° to 100° F.) ; and a hot bath from 38° to 43° C. (100° to 110° F.). Tepid, warm, or hot baths are used principally as cleansing agents or as therapeutic measures. They cause dilatation of the cu- taneous capillaries, diminish blood-pressure, and reduce nervous excitability. The hot bath is also a method of restoring warmth to the body in cases of shock, or to remove the immediate effects of injurious exposure to low temperature. The so-called Eussian and Turkish baths, so popular in the larger cities of this country, are modifications of vapor- and hot-air baths, or rather combinations of these with cold baths. The Turkish bath is especially to be recommended for its depurative and invigorating effects. Cold baths are used not merely for their cleansing effects, but principally for their stimulating effects upon the system. When first plunging into a cold bath there is usually a momentary shock; the respiration is gasping, and the pulse is increased in frequency. These symptoms disappear in a few moments, however, and reaction follows. To a healthy person a cold bath is a delightful general stimulant, removing the sense of fatigue after physical exertion and causing an extremely refreshing sensation throughout the body. As a therapeutic measure, the cold bath has a wide field of use- fulness. For the reduction of the bodily temperature in fevers and inflammatory diseases, and especially in heat-stroke, it is more prompt and effective than any other agent at the command of the physician. Sea-bathing. — The most stimulating form of the cold bath is doubtless the salt-water bath as taken at the sea-shore. The revul- sive effect of the impact of the waves and breakers upon the skin and the stimulation due to the saline constituents of the sea-water heighten the invigorating effects of the simple cold bath. The beneficial results of sea-bathing are, however, not entirely due to the bath, but are to a great degree dependent upon the bracing air of the sea-shore, absence of the care and anxieties of business, and the temporary change in food and habits that a residence at the sea-side involves. Neverthe- less, salt-water baths are more stimulant to the skin than those of simple water, and part of the good effects of sea-bathing can often be obtained from a salt-water bath taken at home. The following mix- BATHS AND BATHING. 359 ture of salts dissolved in about 125 litres of water for one bath makes a fairly good substitute for a sea-bath : — Take of Chloride of sodium (common salt) .... 4 kilogrammes. Sulphate of sodium (Glauber's salt) . . 2 " Chloride of calcium % kilogramme. Chloride of magnesium 1% " There is a prevalent popular belief that it is extremely dangerous to enter a cold bath when heated or perspiring. The author is of the opinion that this belief is erroneous. The stimulant and brac- ing effects of the cold bath are most manifest if it be taken while the individual is very warm or bathed in perspiration. Several years ago the author made a series of observations upon himself to determine the effects of the cold bath when the body was warm. Every afternoon a free perspiration was provoked by a brisk walk of about 2 kilo- metres in the sun. As soon as the clothing could be cast off, and while the body was still freely perspiring, a plunge was taken into a fresh- water bath of about 15.5° C. (60° F.). No ill results followed; on the contrary, the sensation immediately following the bath, and for six or eight hours afterward, was exceedingly pleasant. The health remained perfect, and the weight decidedly increased during the two months the practice was continued. There is probably no danger to a healthy person in this practice, but it is considered advisable to immerse the head first ("take a header"), to avoid increasing the blood-pressure in the brain too greatly, which might result if the body were gradually immersed from the feet upward. The following series of rules have been issued by the English Eoyal Humane Society, and are all worth observing by bathers : "Avoid bathing within two hours after a meal. Avoid bathing when exhausted by fatigue or from any other cause. Avoid bathing when the body is cooling after perspiration. Avoid bathing altogether in the open air, if, after having been a short time in the water, there is a sense of chilliness, with numbness of the hands and feet; but bathe when the body is warm, provided no time is lost in getting into the water. Avoid chilling the body by sitting or standing undressed on the banks or in boats, after having been in the water. Avoid re- maining too long in the water, but leave the water immediately if there is the slightest feeling of chilliness. The vigorous and strong may bathe early in the morning on an empty stomach. The young, and those who are weak, had better bathe two or three hours after a meal ; the best time for such is from two to three hours after break- 360 TEXT-BOOK OF HYGIENE. fast. Those who are subject to giddiness or faintness, or suffer from palpitation or other sense of discomfort at the heart, should not bathe without first consulting their medical adviser." To these instructions may properly be added that a warm or hot bath should be avoided if the person is liable to exposure to cold within a few hours after the bath; that women should, as a ru'e, not take a cold bath while menstruating, or during the last two months of pregnancy; and that persons suffering from organic heart disease should especially avoid surf-bathing. After bathing the body should be thoroughly dried with soft towels, otherwise eczematous eruptions are liable to follow in tlie parts subject to friction from opposing surfaces of the skin, as in the groins, the perineum and inner surface of the thighs, the armpits, or the under surface of the breasts in women in whom these organs are large and pendant. Friction of the skin with a coarse towel, or so-called "flesh- brush," is a popular practice, but is not to be universally commended. The hyperemia of the surface thus produced may sometimes induce cutaneous diseases (erythema, eczema, psoriasis) in those predisposed. One of the most serious dangers of cold bathing, but which is not sufficiently appreciated, is the tendency to nausea and vomiting if the stomach contains much food. There can be no doubt that many cases that are called "cramp," and which frequently result in drown- ing, are due to this cause.^ Cramps of the various muscles sometimes occur, rendering the bather helpless, and if in deep water he is liable to drown before as- sistance can reach him. In drowning death takes place by asphyxia. The respiration is arrested by the submersion of the head, the carbonized blood gradually poisons the system, and the heart ceases to beat. So long as the heart will react to its appropriate stimulus the person may be restored to life. The first thing to do, therefore, after a recently-drowned per- son is taken out of the water, is to attempt to re-establish the arrested respiration. Several methods are in use for this purpose. Sylvester's is one of the simplest. It is as follows: — The body being placed on the back (either on a flat surface or, better, on a plane inclined a little from the feet upward), a firm cushion or similar support (a coat rolled up wil answer) should be placed under the shoulders, the head being kept in a line with the ^ So far as the author is aware. Dr. John Morris, of Baltimore, first called especial attention to this source of danger. BATHS AND BATHING. 361 trunk. The tongue should be drawn forward to raise the epiglottis and uncover the windpipe. The arms should be grasped Just above the elbows and drawn upward until they nearly meet above the head, and then at once lowered and replaced at the side. This should be imme- diately followed by pressure with both hands upon the belly. Just below the breastbone. The process is to be repeated fifteen to eighteen times a minute. Several years since the Michigan State Board of Health published a method which is comprehensive, effective, easily understood, and readily carried out. This method has also been adopted by the United States Life- Saving Service. The following are the details of the Michigan method: — Eule 1. — Eemove all the obstructions to breathing. Instantly loosen or cut apart all neck- and waist- bands; turn the patient on his face, with the head down hill; stand astride the hips with your face toward his head, and, locking your fingers together under his belly, raise the body as high as you can without lifting the forehead off the ground, and give the body a smart Jerk to remove mucus from the throat andwater from the windpipe, hold the body suspended long enough to slowly count one — tivo — three — four — five, repeating the Jerk more gently two or three times. Rule 2. — Place the patient on the ground face downward, and, maintaining all the while your position astride the body, grasp the points of the shoulders by the clothing; or, if the body is naked, thrust your fiugers into the armpits, clasping your thumbs over the points of the shoulders, and raise the chest as high as you can with- out lifting the head quite off the ground, and hold it long enough to slowly count one — tivo— three. Replace him on the ground with his forehead on his flexed arm, the neck straightened out, and the mouth and nose free; place your elbows against [the inner surface] your knees and your hands upon the sides of his chest over the lower ribs, and press downward and inward with increasing force long enough to slowly count one — two. Then suddenly let go, grasp the shoulders as before, and raise the chest ; then press upon the ribs, etc. These alternate movements should be repeated ten or fifteen times a minute for an hour, at least, unless breathing is restored sooner. Use the same regularity as in natural breathing. Rule 3. — After breathing has commenced restore the animal heat. Wrap him up in warm blankets, apply bottles of hot water, hot bricks, or anything to restore heat. Warm the head nearly as fast as the body lest convulsions come on. Rubbing the body with warm cloths or 362 TEXT-BOOK OF HYGIENE. the hands and slapping the fleshy parts may assist to restore warmth and the breathing also. If the patieiit can surely swallow, give hot coffee, tea, milk, or a little hot sling. Give rpirits sparingly, lest they prodvice depression. Place the patient in a warm bed, and give him plenty of fresh air. Keep him quiet. Beware ! Avoid delay. A moment may turn the scale for life or death. Dry ground, shelter, warmth, stimulants, etc., at this moment are nothing — artificial breathing is everything — is the one remedy — all others are secondary. Do not stop to remove wet cloth- ing. Precious time is wasted and the patient may be fatally chilled by exposure of the naked body, even in summer. Grive all your at- tention and efforts to restore breathing by forcing air into, and out of, the lungs. If the breathing has just ceased, a smart slap on the face or a vigorous twist of the hair will sometimes start it again, and may be tried incidentally. Before natural breathing is fully restored, do not let the patient lie on his back unless some person holds the tongue forward. The tongue by falling back may close the windpipe and cause fatal choking. Do not give up too soon; )^ou are working for life. Any time within two hours you may be on the very threshold of success without there being any sign of it.* ^ In all large cities and towns provision should be made for free public baths, conducted under official supervision, and for the especial use and benefit of the poorer classes. General cleanliness is not merely a factor in the preservation of the public health, but there is good reason to believe that the cause of good order and decency would likewise be promoted by furnishing the public the means of easily and cheaply keeping clean. Many cities in the country have established public baths upon an increasingly generous scale, and these are very popular and have doubtless been of great benefit. The author has shown^ that about five-sixths of the inhabitants of the large cities in the United States have no facilities for bathing except such as are afforded by a pail of water and sponge, or in summer the proximity of some body of water easily accessible. The most economical and best form of bath for public use would doubtless be the needle or rain bath recommended by the author in the paper referred to. Mr. W. P. Gerhard has also stronglv advocated this form of bath. * Report of Michigan State Board of Health, 1874, pp. 91-99. ° Address in State Medicine, Journal American Medical Association, July 2, 1887. CLOTHING. 363 It would be well if boards of health and building commissioners would issue no permits for dwelling-houses, the plans for which do not include proper water-supply and bathing facilities. CLOTHING. The primary object of clothing is the protection of the body against the injurious influences of heat, cold, and moisture. Second- arily, the moral sense of civilized communities demands that the nude human body shall not be exposed in public. Hence, there are moral as well as sanitary reasons for the wearing of clothing ; only the latter can be considered in this place. Bodies radiate or absorb heat accordingly as they are surrounded by a medium having a lower or a higher temperature than themselves. In order, therefore, to avoid chilling of the human body if exposed to a temperature below 37° C. (98.6° F.), clothing must be worn to prevent or retard radiation of the body-heat. Exposure of the un- protected body to a low temperature would not only cause chilling of the surface owing to the rapid loss of heat, but would incidentally produce congestion of internal organs by causing constriction of the superficial capillaries. Clothing is also worn as a protection against great heat. The head, especially, needs protection from the sun's rays. Evidence is accumulating to the effect that direct sun-light, if excessive, is equally injurious. The materials from which clothing is made are, principally, cotton, linen, wool, silk, and the skins of animals. Of these, prob- ably the most universally used is cotton. It is cheap, durable, does not shrink when wet, absorbs little water, and conducts heat readily. It is therefore especially valuable for summer garments, allowing rapid dissipation of the body-heat and evaporation of the perspiration. Linen conducts heat even better than cotton, and is for this reason largely used for summer clothing. Its principal advantage over cotton is that it is more durable and less harsh to the skin. Wool absorbs water readily and is a bad conductor of heat. It is therefore valuable as a winter garment, retarding radiation from the body. Woolen undergarments should be worn at all seasons, in order to prevent too rapid changes of the surface, and so invoking dis- eases depending upon chilling of the body. Clothing of pure wool (flannels) is lia})le to irritate the skin of some persons. A mixture of wool and collon, known us "Saxony wool," is softer and less irritating, and makes a serviceable substitute for pure wool. 364 TEXT-BOOK OF HYGIENE. Silk is often used for undergarments. It is light, soft, and a bad conductor of heat. Linen-mesh combines the advantage of both cotton and wool, and is an excellent material for undergarments. The skins of anima's, with the fur on, are often used for outside clothing. They furnish great protection against severe cold. The skin is impermeable to wind and rain, while the thick, pilous covering of fur retards to a very great degree the radiation of heat. In British America, the Northwestern States and Territories, and in the Arctic regions, the use of skin clothing is necessary for comfort. As a protection against moisture (rain and snow) rubber doth is used for overcoats, etc., but it is not now so much employed as for- merly, because, while it serves effectually in keeping out the rain, it prevents evaporation of the perspiration, increasing the liability to chill, and rendering the person wearing it very uncomfortable, except in cold weather. Outer garments waterproofed after the method known as the "Cravenette" process, and made of almost any mate- rial desired, are now substituted. Leather is used almost exclusively in the manufacture of foot- wear. It is sometimes used, however, for other articles of clothing, such as coats, trousers, etc. It furnishes most effective protection against cold. The color of the clothing is of great importance. Exposed to the sun, white wool or silk absorb very little more heat than linen or cotton, but the same material, of different colors, when exposed to the sun's rays, exhibits marked differences in absorptive capacity. The following table shows the results of some experiments of Petten- kofer. The material used was cotton shirting of the colors named :— - White absorbed 100 heat units. Light Sulphur Yellow absorbe 1 102 Dark Yellow absorbed 1 '0 Light Green absorbed 155 Turkey Red absorbed 165 Dark Green absorbed 1C8 Light Blue absorbed 198 Black absorbed 208 When protected from the sun's rays, liowever, the material be- comes important and the color is of little consequence. Wool, being a bad conductor of heat, retards radiation from the body, and is hence the best material for winter clothing. Gases and vapors are absorbed by clothing and also disease-germs CLOTHING. 365 may be conveyed from place to place. It has been found that woolen clothing possesses this power of absorption to a much greater degree than linen or cotton. The bad odor of a crowded room or of tobacco- smoke frequently clings to woolen garments for days, although they may be exposed constantly to the air during the interval. It would be advisable, therefore, that physicians attending infectious diseases, hospital attendants and nurses, should wear linen or cotton clothing instead of woolen. Clothing should be made to fit properly. It shouM not restrain muscular movements, obstruct the circulation, or compress organs. Hence, corsets, belts, and garters are to be condemned. It is a fact of common observation that moderately loose clothing is warmer than close-fitting. Especial attention should be given to the shape and fitting of foot- wear. Boots and shoes are usually made with little regard to the physiological anatomy of the foot, and as a result the feet of most Americans are deformed, beauty and usefulness being in a great de- gree sacrificed to the Moloch of fashion.*' Dyes used for coloring fabrics are sometimes poisonous. The author has repeatedly seen troublesome eruptions, and even ulcerations of the legs, from wearing stockings dyed with aniline compounds. By appropriate treatment clothing can be made non-inflammahle. Tungstate and phosphate of soda are used to reduce the inflammabil- ity of fabrics. The addition of 20 per cent, of tungstate of soda and 3 per cent, of phosphate of soda to the starch-sizing used for stiffening linen is effective. The material is not injured by it, and a smooth sur- face and polish can be obtained under the hot iron. Prof. Kedzie has recommended borax for the same purpose. He says: "The sim- plest and easiest way to make your cotton and linen fabrics safe from taking fire is to dissolve a heaped teaspoonful of powdered borax in one-half pint of starch solution. It does not injure the fabric, im- parts no disagreeable odor, and interferes in no way with the subse- quent washing of the goods. It does not prevent the formation of a smooth and polished surface in the process of ironing. Borax can be found in every village, and is within the reach of all. It is a cheap salt, and its use for this purpose is very simple."'^ " See a practical paper by Dr. Ben j. Lee, A Shoe That Will Not Pinch, in Ran Italian for June, 1884, p. 49.3. ''Michigan State Board of Health, p. LSI, 1880. 366 TEXT-BOOK OF HYGIENE. RECREATION AND REST Eecreation is not by any means idleness, but a variety of occu- pation, and oftentimes is hard physical work. By its means a relaxa- tion of both mind and body from the worries and fatigues of one's daily avocation may be effected. No rule can be laid down as to the exact amount of sleep necessary, for it is a matter of habit, age, and temperament. Generally speaking, young persons require more sleep than the aged. The most refreshing sleep is supposed to be that taken during the early hours of the night, but the habit, where necessary, of sleeping any time during the twenty-four hours may be acquired. The following simple rules should be observed : — Do not eat heavy meals late at night. Have fresh air in the sleeping-room the year round, but do not have the bed in a draught. Do not sleep with an artificial light burning in the room; it requires increased provision for ventilation, and, by shining in the eyes, pro- duces inflammatory troubles of the lids. Do not have carpets or hangings in the sleeping-room, but let the furniture be of the very simplest kind. If two people occupy the same room, they should oc- cupy separate beds. Do not sleep in any garments worn during the day. Have the night-garments loose and comfortable: warm in winter, cool in summer. Have the bed-coverings light but warm, remembering that a number of layers makes a warmer covering than the same weight of material woven in one piece. Do not sleep on feather beds. Sleep with the head low and not with it propped up on several pillows, because this interferes with deep breathing, con- tracts the chest, and favors stoop shoulders. Lie on the right side when you first go to bed ; it hastens food which may be in the stom- ach towards the pylorus and aids digestion, favoring natural sleep. QUESTIONS TO CHAPTER XIII. EXERCISE AND TRAINING. What is absolutely necessary for the maintenance of the healthy func- tions of the body? What is the efTect of disuse upon any organ? Of train- ing? What occurs when a muscle contracts? What is the result of increased activity of circulation in a muscle? What is the effect of muscular action on the respiratory process? What is the difference as to the absorption of oxygen in a state of rest and during work? As to the elimination of carbon dioxide and water? What is the effect of muscular action upon the circu- lation? Upon the cutaneous transpiration? What is the effect of systematic training upon health and longevity? What are some of the principal and best methods of physical training? What is one of its most important objects? How may the various methods be com- bined with benefit? What should be included among the studies and work of all public schools? For what purposes? What is the tendency among instructors in physical training? Is this necessary, or not? Why? What is an important preliminary to all methods of training? Why? How may a pupil be taught to assume and maintain a correct position and carriage of the body? How should a person walk? What attention should be given to the clothing worn during exercise? What will be some of the results of sys- tematic physical training properly pursued? What are some of the results of overexertion? Does it make a difference whether the exercise is too long uninterrupted or whether it is excessive in amount and character? BATHS AND BATHING. What is the most important object of bathing? For what other pur- poses may baths be taken? What are the respective temperatures of so-called cold, tepid, warm, and hot baths? What are the physiological effects of the last three? In what surgical emergencies may the hot bath be used? For what are cold baths used? What are their physiological effects? How m^y the cold bath be used therapeutically? What is the most stimulating form of cold bath? To what are its beneficial effects due? How may a salt-water bath be prepared at home? Is there any danger to the healthy in cold bathing while the body is per- spiring freely? What precaution should be taken before entering a cold bath? What rules may be laid down for bathing in the open air? When is the best time for bathing? Who should not bathe without previous medical advice? When should hot baths not be taken? What should follow all baths? (367) 368 TEXT-BOOK OF HYGIENE. What is one of the most serious dangers of cold bathing? How does death take place in drowning? What is the indication that one apparently drowned may still be restored to life? Describe Sylvester's method of arti- ficial respiration. What is the method adopted by the United States Life- Saving Service? W^iat is essential after breathing has been re-established? How should spirits be given? How long should efforts to restore respiration be continued? What is to be avoided? What are some of the arguments in favor of public baths in large cities ? What is the most economical form of bath for public use? CLOTHING. What is the primary object of clothing? What are some of the sec- ondary objects? What are the probable results of exposing the unprotected body to low temperature? What part of the body needs special protection against heat? What are the principal materials from which clothing is made? Which of these is most universally used? Why? In what respect is linen superior to cotton? Why are cotton and linen not suited for winter wear or cold climates? Why are silk and wool better for such uses? Why should wool be worn next the skin? \Miat gives silk its value? Why are furs so warm? What are some of the objections to the use of rubber clothing? For what is leather chiefly used? Of what importance is the color of the clothing? What colors absorb least and what ones most heat? If protected from the sun's rays, which is the most important in the absorption of heat, material or color? What deleterious or harmful matters are absorbed or cling to clothing? What kinds of clothing have the greatest power of absorption? What pre- cautions should those attending cases of infectious diseases observe? Why should clothing fit properly? What parts of the clothing should not be too tight? What disturbances may result from the wearing of cloth- ing that is too tight? How may improperly-dyed clothing create trouble? How may clothing be rendered practically non-inflammable? CHAPTER XIV. DISPOSAL OF THE DEAD. When life is extinct in the animal body decomposition begins. This may be either putrefactive or non-putrefactive. The difference between the two processes has been explained by Liebig. In putre- faction of organic matters only the elements of water take part in the formation of the new compounds which result, while in non- putrefactive decomposition or decay the oxygen of the air always plays an important part. Putrefaction can go on under water, while decay can only take place when the supply of free oxygen is abundant. The prompt removal of the bodies of the dead from the imme- diate vicinity of the living is a matter of prime sanitary importance. If death results from a contagious or an infectious disease, the neces- sity for the removal of the corpse is evident. But, even where there is no danger of propagation of infectious disease, the products of putrefaction and decay may give rise to serious derangements of health if allowed to pollute the air. The chief methods of disposal of the dead are burial in the earth, entombment in vaults, and cremation. INTERMENT. The most common method of sepulture is burial in the earth. The corpse is usually inclosed in a case (coffin) of wood or metal, and buried from 1 to 3 metres deep. Here decomposition sets in, which is at first putrefactive and later on non-putrefactive. In the course of several years, from five to ten, the entire body, with the exception of the bones, has usually disappeared and become converted into a dry mold. The soil of a burial-ground should be dry and porous, so as to be easily permeated by the air. In a sandy or gravelly soil the decay of a corpse is much more rapid than in a moist, clayey soil. In the latter the bodies more readily undergo putrefaction, or become con- verted into a sul)stanee termed adipocere. It has been calculated that in a gravelly soil the decay of a corpse advances as much in one year as it would in sand in one and two-thirds, and in clay in two and ono-tbird years. The decay of the dead bodies is dependent upon the presence of living vegetable organisms. If the access of free oxygen 24 (369) 370 TEXT-BOOK OF HYGIENE. is prevented, the bacteria of putrefaction will thrive and cause pu- tridity. If, however, the soil is loose, porous, and easily permeable by the air, the bacteria of decay will be present and produce their characteristic effects. The barometric pressure seems to affect the decomposition of dead bodies. For example, at the refuge of St. Bernard, in the high Alps, the bodies of those dying are not buried, but exposed to the air, where they undergo a drying, shrinking, and mummification instead of putrefaction or decay. Alternate saturation and drying of the soil promotes the rapidity of decay. Certain occupations are said to produce changes in the tissues which resist decay. Thus, tanners are supposed to resist the final changes of the tissues longer than persons of other occupations. Shakespeare makes the grave-digger in Hamlet say: "A tanner will last you nine years.'' The corpses of those poisoned by phosphorus, arsenic, sulphuric acid, or corrosive sublimate also decay more slowly than in cases of infectious diseases. All the tissues may be converted into adipocere, but in the large majority of cases only the fat and connective-tissues undergo this change. SUPPOSED DANGERS OF BURIAL=GROUNDS. Popular sanitary literature teems with supposed instances of the injurious influences of cemeteries upon the health of persons living in their vicinity. An unprejudiced consideration of the subject shows,, however, that there is no trustworthy evidence that any of the gases exhaled by decaying or putrefying bodies are injurious to health. The air of closed burial-vaults may be dangerous from the large proportion of carbon dioxide contained in it, but the other gaseous products of decomposition have no deleterious effects. The dangers to health from the proximity of cemeteries are doubtless very much exagger- ated. Pettenkofer and Erismann have shovrn that a single large privy- vault, containing about 17 cubic metres of excrement, gives off nearly as large an amount of putrefactive gases in the course of one year as is exhaled by a burial-ground containing 556 decomposing corpses in ten years. Where bodies are properly buried, and the ground is not over- charged by corpses, it is not probable that infectious diseases are pro- pagated from interred bodies. There are no facts on record which show that such an event has occurred. CREMATION. 371 The dangers of pollution of water by cemeteries have also been much overestimated. The purifying power of soil strata, through which the water is compelled to percolate before reaching the well after becoming charged with the products of decomposition, is in most cases sufficient to remove all deleterious matters. It must be admitted, however, that it is not desirable to have a well or other source of water-supply in close proximity to a burial-ground. Cemeteries should not be located within a city, but must be easily accessible. The soil should be dry gravel or sand, with a low ground- water level. The graves need not be deeper than II/2 metres to the top of the coffin. ENTOMBMENT IN VAULTS. Burial-vaults in churches or in the open air should be discoun- tenanced. The gases of decomposition are given off directly to the air without the modifying power of the soil, and often constitute a nuisance, even if not deleterious to health. Entombment in vaults or crypts has not a single favorable circumstance to recommend it. CREMATION. Within recent years the rapid incineration of the dead in properly-constructed furnaces has been frequently recommended. In the United States a cremation furnace was built years ago at Washing- ton, Pa., by the late Dr. J. C. LeMoine. Among the remains of those cremated were those of the late Dr. Samuel D. Gross, the distin- guished surgeon. The practice has not gained very many adherents. hoAvever, although cremation societies have been organized and fur- naces built in several of the cities throughout the country. Aside from the objections urged by the more conservative classes, who de- sire to adhere to the time-honored custom of interment, serious legal objections have been brought forward. In cases where poisoning is suspected some time after death, the cremation furnace would have destroyed every evidence of crime, and conviction of a criminal poisoner could not be obtained. The real advantages of cremation, such as rapid destruction of a corpse, economy of space in keeping the remains, and avoidance of pollution of the soil by decaying bodies, and possible pollution of air and water, are more than counterbalanced by the expense and the medico-legal objection mentioned. From a sanitary point of view, cremation is not necessary in this country. A proper regulation of cemeteries will prevent any possible dangers to the living from pollu- tion of the ail', soil, or water by the decaying remains of human beings. 372 TEXT-BOOK OF HYGIENE. INTERMENT ON THE BATTLE=FIELD. After battles, the disposal of the bodies of the slain is often a serious problem. Naegeli proposes the following method of inter- ment : After selecting the place of burial, the sod and la3^er of humus are removed from a sufficiently large surface and thrown to one side. The corpses are then laid upon the denuded place, and the layers of corpses separated by sand, gravel, or fine brush-wood. A trench is then dug around the pile of dead and the soil gained is thrown over the corpses until they are covered to a depth of 1 metre, when the humus and sod are placed over the whole. This furnishes a dry grave in which decay rapidly takes the place of putrefaction, and the corpses soon molder away. The same procedure may be followed in cases of epidemics where the number of deaths is too great to prop- erly bury them in single graves. Before leaving this subject it may be well to consider the matter of funerals. The pernicious custom of public funerals in cases of contagious diseases cannot be too strongly condemned. In fact, pub- lic funerals in such cases should not be permitted by the health au- thorities. To minimize the danger, the bodies of persons dead of con- tagious diseases should be wrapped in sheets wet with a solution of bichloride of mercury (1:500), and the coffin kept securely closed. Still more pernicious is the custom of disposing of the clothing and other personal property of the dead of contagious diseases by either distributing them among friends, donating to the poor, or selling to second-hand dealers. Many epidemics of contagious -diseases have had their origin in this way. There should be a strict law prohibit- ing the sale of any article with which the deceased has come in con- tact during the last illness, unless such article is thoroughly disin- fected. QUESTIONS TO CHAPTER XIV. DISPOSAL OF THE DEAD. What is the difference between putrefactive and non- putrefactive decom- position? Why must the dead be removed from the living? What are the chief methods of disposal of the dead? Which is the most common? Why should the soil of burial-grounds be dry and porous? Upon v/hat is the decay of dead bodies dependent? What is the usual length of time re- quired for the decay of a human body? What may affect the length of this period? What changes other than decay may the body undergo? Is there any evidence that the air from cemeteries is dangerous to health? In what way may the air from a closed burial-vault be detrimental? Is it probable that infectious disease-germs are disseminated from dead bodies ? Is the pollution of water by cemeteries probable? What agents serve to pre- vent this? Where should cemeteries be located, however? Why should en- tombment in vaults be discountenanced? What are the advantages of cremation? What are the objections to it? Is it necessary, from a sanitary point of view, in this cormtry? How may the bodies of the dead be interred after battles, or in case of very fatal epidemics? What are the advantages of this method? What precautions should be observed in cases of contagious diseases? (373) CHAPTER XV. THE GERM THEORY OF DISEASE. The ruling doctrine in tlie pathology of the jDresent clay is the germ theory of disease. Based upon the doctrine of omne vivuni ex vivo, and supported by strong experimental and clinical evidence, it is accepted by the great majority of physicians. Its advocates claim that the large class of diseases known as contagious or infectious are all due to the presence in the blood or tissues of minute organisms, either animal or vegetable. Many other diseases, not at present in- cluded in the above class by general pathologists, are also believed, by the adherents of the germ theory, to be caused in the same Avay, The following constitutes a brief review of the most prominent facts in the history of the doctrine: — The doctrine of the vital nature of the contagion of disease — the contagium animatum of the older writers — was held in a vague way by many of the physicians of the past, but it was not until the latter part of the last century that the theory took definite shape. In the works of Hufeland, Kircher, and Linne, the idea is expressed with more or less directness that the propagation of infectious dis- eases depends upon the implantation of minute independent organ- isms into or upon the affected individual. This hypothesis was, how- ever, first clearl}^ enunciated and defended with great force by Henle in 1840. Three years earlier, Cagniard de la Tour and Schwann had established a rational basis for the theory by their observations upon the 3^east-plant and its relation to fermentation. In 1835 Bassi had discovered in the bodies of silk-worms affected by muscardine, a dis- ease of these insects which proved very destructive, a parasite which was soon shown to be the cause of the disease. Within the next few years, Tulasne, DeBarry, and Kuehn proved that certain fungi were the causes of the potato-rot and other diseases of plants. Schoenlein, Malmsten, and Gruby, between 1840 and 1845, demonstrated that those skin diseases of man classed as the tinece were due entirely to the action of vegetable parasitic organisms. Up to this time the germ theory, as now accepted, had received no support from experiments. All the diseases claimed as parasitic were purely local ; so far as the parasitic nature of the general dis- eases was concerned, all was hypothetical. In 1849, Guerin Meneville (374) THE GERM THEORY OF DISEASE. 375 discovered a corpuscular organism in the blood of silk-worms affected by the pehrine, which was later proven by Pasteur to be the true cause of this destructive disease. Pollender, in 1855, and Brauell, in 1857, found numerous minute rod-like organisms (bacteria) in the blood of animals dead from splenic fever or anthrax. In 1863 Davaine in- vestigated the subject more fully, and showed beyond doubt that the little organisms discovered by Pollender were the true cause of an- thrax. The more recent researches of Eobert Koch upon the history of these bacteria or bacilli of splenic fever have removed all doubt of their etiological significance. Sarcina (Packet-cocci) Cocci With capsules Staphylococci Streptococci Diplococci Tetracocci Ciliated cell -^ . ' Spider cell Diplococciis Tetracoccus a >a /-^/^ (. Monococcus Centrally situated spores Clostridia forms Knobbed bacteria with tenninal spores / *w\^ .i|4 Zoogloea m Slender bacilli Short bacilli Bacilli in chains Vibrios (spirilla^ Comma bacilli Spirochaetse Pig. 43. — Forms of Bacteria. (From Schenk. ) In 1883 the last-named observer startled the medical world by the assertion that consuinption or tuberculosis was a disease of microbic origin, and dependent upon the presence, in the affected 376 TEXT-BOOK OF HYGIENE. tissues^ of an organism which he named Bacillus tuberculosis. Much controversy arose upon this point, but Koch fortified his position so strongly with proofs, both exp.erimental and clinical, that it may now be regarded as fully demonstrated. Koch has likewise shown (1885) that Asiatic cholera is due to a bacterial organism, termed by him the "comma bacillus," from its shape. It is generally regarded by bacteriologists, however, to belong to the class of organisms known as spirilla, and not to the bacilli. Eberth discovered the bacillus which is now generally accepted as the cause of typhoid, in 1880 ; Fehleisen, the micrococcus of erysipelas, in 1883 ; Obermeier, the spirillum of relapsing fever, in 1868; Schutz and Loffler discovered the bacillus of glanders in 1882; I^eisser announced the discovery of the micro- coccus of gonorrhea in 1879. The bacillus of leprosy was discovered by, Hansen, in 1879. The micro-organism of malaria (plasmodium malarije), which is an animal organism, was discovered by Laveran. in 1881. This organism is different from the Bacillus malarice of Klebs and Tommasi-Crudeli, which possesses no pathological signifi- cance. Pneumonia may also be regarded as a microbic disease, since Sternberg^ Weichselbaum, and Frankel have shown the constant pres- ence of the diplococcus lanceolatus in the sputa in that disease. In 1884, Nicolaier and Eosenbach proved that tetanus is due to a bacil- lus. Bacillus tetani. In the same year Loffler isolated the diphtheria bacillus, observed previously by Klebs. In 1892, Cauon and Pfeiffer discovered the bacillus of influenza, and in 1891, Ycrzin and Kitasato independently isolated the bacillus of bubonic plague. The careful observations and researches of the investigators mentioned, as well as of many others who have worked earnestly in this field, have established the germ theory of disease upon a secure foundation. For the diseases mentioned the parasitic origin may be accepted as fully proven. For a number of others, among which may be mentioned small-pox, yellow fever, scarlet fever, typhus fever, measles, hydrophobia, etc., the etiological connection between the dis- ease and certain hypothetical organisms not yet discovered appears highly probable. In connection with the germ theor}'- there has arisen of late a very important question in its bearing upon preventive medicine. This is the value of the so-called protective inoculations against in- fectious diseases. The protective influence of vaccination against small-pox is firmly established by indubitable evidence. Within re- cent years a procedure introduced by Pasteur to protect animals against certain fatal infectious diseases, such as splenic fever, fowl- THE GERM THEORY OF DISEASE. 377 cholera, and rabies, has claimed much attention. Pasteur's observa- tions were first made upon the disease termed chicken-cholera. He found that the blood of the dead fowls, or of those attacked by the disease, swarmed with bacteria. Inoculations of healthy fowls with this diseased blood, or with the bacteria alone, carefully freed from all animal fluids, produced the same disease. The bacteria were there- fore assumed to be the cause of the disease. The investigator then took a quantity of these bacteria and '^'cultivated" them through a number of generations, using sterilized chicken-broth as a culture medium. Fowls inoculated with the result of the last cultivation were 'still attacked by the same symptoms, but in a very mi'd degree, and almost uniformly recovered from the disease. On subsequent inocu- lation with infected blood no effect was produced upon the '"Vaccin- ated" fowls, while the same blood introduced into fowls not "pro- tected" by the previous inoculation produced its customary fatal effect. Pasteur and others repeated these experiments with the organisms found in the blood in splenic fever and obtained similar results. In- oculations made with emulsions from the desiccated spinal cords of animals that died from rabies have also proven protective against this disease. These protective inoculations have been made upon large numbers of sheep, cattle, and man, with very remarkable success. The "protective inoculations" produce an immunity which is more oi less lasting. The most important discovery along the lines of immunity was made by Behring, in 1893. This observer found that if diphtheria bacilli are cultivated in bouillon for about a week, the medium con- tains the toxic substances of the bacilli in solution. The bacilli may then be entirely removed by filtration and the clear fluid represents the toxin, of which about 0.001 cubic centimetres will kill a guinea- pig weighing 250 to 300 grams. If this toxin is injected into an animal in gradually increasing doses, neither of which ig large enough to prove fatal, the animal acquires an immunity to the diphtheria toxins, which are the products of the diphtheria bacillus. Now, the blood-serum of this immunized animal is capable of neutralizing the toxic properties of the diphtheria toxin either in the test-tube or in the body of another animal ; in other words, the blood-serum con- tains antitoxins. For practical purposes, a healthy horse is injected with gradually increasing doses of toxin, beginning with 0.1 cubic centimetres and ending with several doses of 500 cubic centimetres each. At the end of about six weeks from five to nine quarts (according to the size of the 378 TEXT-BOOK OF HYGIENE. horse) of blood are withdrawn from the jugular vein, the blood al- lowed to coagulate, and the clear eerum prepared for the market. This serum is the diphtheria antitoxin. This antitoxin, when injected into a person suffering from diphtheria, Avill neutralize all of the free toxins circulating in the b'.ood, and the outcome of the case de- pends entirely on whether, at the time the antitoxin is used, the toxin particles are mostly free or combined with the tissue cells. In the latter event the antitoxin is powerless to accomplish very much, and the issue is fatal. It is for this reason that the modern physi- cian emplo3^s antitoxin at the earliest possible stage of the disease, so as to neutralize the free toxins before they have a chance to combine with the cells. For this reason also a small dose of antitoxin, when injected into persons exposed to the infection, may prevent the de- velopment of the disease. The introduction of antitoxin in the treat- ment of diphtheria has reduced the mortality from diphtheria from 50 to about 10 per cent. Tetanus antitoxin, elaborated by Behring and Kitasato, in 1890, is based on the same principles and prepared very much in the same manner, with the exception, of course, that the tetanus bacillus is cultivated under anaerobic conditions. From a therapeutic stand- point, however, the antitoxic serum is not as useful as in the case of diphtheria. The reason given is that by the time the symptoms of tetanus develop, the toxin is practically combined entirely with the nerve-cells and, therefore, cannot be neutralized. On the other hand, when the antitoxin is used at the time the invasion of the bacillus occurs, or during the period of incubation, the development of the disease may be prevented with absolute certainty. It is this fact that led veterinarians to use tetanus antitoxin in every case of suspicious wound in a horse, a practice which should be followed by the physi- cian in case of any suspicious wound in man. The immunity conferred by the use of antitoxins is passive and temporary, the body of the patient not participating in its production. In the case of other infections which are caused by micro-organisms not possessing soluble toxin, the immunization must be active, and can only be accomplished artificially by the employment of "vaccines" prepared from the bodies of the dead germs. This form of immu- nity, which may be cal'ed "bacterial," depends for its production on altogether different forces, namely, the property of the white blood- cells to attract and devour bacteria, or, as MetchnikofP termed it, "phagocytosis." However, before invading micro-organisms can be imbibed by the phagocytes they must be acted upon or prepared by THEORIES OF IMMUNITY. 379 another substance which is present in the blood. This substance, whatever its nature, renders the bacteria capable of becoming im- bibed by the phagocytes, and has been recently designated by Wright and Douglas as "opsonins" (from opsono, I prepare food for). The relative power of phagocytosis in the blood of a patient suffering from an infection, as compared with the phagocytic power of the blood of a healthy individual towards the same germ, is called the "opsonic index." These, however, are not the only defensive forces. There are no doubt a number of other substances in the tissues and fluids of the animal organisms which protect the latter against disease, and it is the weakening of any or all of them that makes infection possible. The subject of immunity is a very wide one, and it is only now that we are beginning to understand it. The time will no doubt come when every infectious disease will be either prevented or cured by stimulating the production of the necessary defensive agents. THEORIES OF IMMUNITY. No treatise on hygiene is complete without a consideration of the factors concerned in the protection of the animal organism against infection, or overcoming infection already present. Broadly speaking, the natural tendency of the body is to keep along the line of health. Any deviation from that line is promptly met by an effort on the part of the organism to correct its course and re-estab- lish a healthy equilibrium. A foreign body in the eye is instantly flooded with tears in order that it may be washed out. Failing in that, an inflammatory reaction is set up, the object being to surround the irritant by adhesion and thus shut it off from further irritation. A fractured limb is immediately placed by Mother Nature in a state of enforced rest, owing to the excruciating pain which the motion of the limb produces, and at first a temporary and then a permanent splint (callus) are placed around the fragments, remaining there until restoration of continuity. Certain poisons which are generated in the course of normal metabolism are neutralized and eliminated so as to prevent self-poisoning. A local invasion of pus-producing bac- teria (staphylococcus, streptococcus, etc.) is a signal for an imme- diate concentration of armies of leukocytes in an attempt to destroy the invader, and, failing in that, an effectual barrier against further invasion is formed through a process of inflammation which results in the formation of a membrane, the so-called pyogenic membrane. The invasion of bacteria into the general circulation, or the absorp- 380 TEXT-BOOK OF HYGIENE. tion of their products (toxins), stimulates the production of sub- stances in the body which destroy the micro-organisms or neutralize their poisons. Thus, the natural forces of the body are continuously at work, maintaining the organism in a state of health. When these forces become inadequate, or are temporarily deranged, disease or a deviation from the normal line results. Immunity may be defined as a natural or acquired resistance to disease. Generally, the term refers to infectious diseases. Immunity may be racial, as the immunity of the negro to yellow fever, or indi- vidual; it may be active, when the result of natural infection or inoculation, 'or passive, when produced by the introduction of sub- stances derived from animals actively immunized, as in the case of antitoxin treatment. Immunity, furthermore, may express itself against the bacteria (antibacterial), the toxins (antitoxic), or against cells from an animal of a different species (cytolytic). In order to more fully appreciate the relation of the subject of immunity to hygienic problems, it may be well to consider briefly the two factors involved in the causation of infectious diseases. These are : the specific micro-organism or the exciting cause, and the resist- ance of the individual or the predisposing cause. The former may be likened to a plant-seed, the latter to the soil. Given a vigorous seed and a poor soil, no growth will take place. Similarly, a favorable soil and a poor seed will remain barren. To get the best results, both the seed and the soil must be in the very best condition. This is precisely the case in infection. A virulent micro-organism remains powerless in the absence of a predisposition, nor will infection occur in the presence of a predisposition with an avirulent micro-organism. As neither viru^.ence nor resistance are constant factors, the resulting infection will vary in each individual case, from a mild to a fatal attack. The virulence of a micro-organism, under natural conditions, is increased by passage through the bodies of susceptible individuals, and decreased by passage through the bodies of relatively insusceptible persons. This explains the rise and fall of an epidemic. At first, the most susceptible individuals in a community are attacked. As the specific micro-organism passes through the bodies of these victims it gains in virulence, and the epidemic gains in fury until the most insusceptible individuals are reached, when the virulence of the micro- organism begins to decline, and the epidemic dies out. The virulence of bacteria may also be influenced by climatic and atmospheric con- ditions and by association of two or more species which either in- creases or decreases the virulence of the respective species. This asso- THEORIES OF IMMUNITY. 381 ciation is known as symbiosis. On the other hand, the predisposition or susceptibility of the individual may be increased by bad hygienic surroundings, chronic poisoning, alcoholism, fatigue, and overwork of the nervous system, exposure to cold, improper diet, drugs, surgical operations, injuries, previous disease. In preventing infection, there- fore, we sliouM aim at a destruction of the bacteria, or at least a reduction of their virulecce by the use of antiseptics, etc., and at the same time we should enhance the resistance of the individual. In other words, we must render the seed inactive and the soil unfavor- able. The accepted theories of immunity are (1) Metchnikoff's theory of phagocytosis and (2) Ehrlich^s side-chain theory. Each explains part of the phenomenon, and the truth probably lies between the two. (1) According to Metchnikoff and his followers, certain cells in the animal body possess, in common with ameba and other unicellular organisms, the property of incorporating and digesting foreign sub- stances. These substances are attracted by the ce Is by a bio-physical process known as chemiotaxis, which may be positive or negative, depending on whether the foreign body is attracted or repelled. The presence of the foreign body within the cell stimulates the production of cellular enzymes, cytases, wdiich act as digestive ferments. The entire process is called phagocytosis, from the Greek c^aysiv, to eat, and * /euros, cell. In the human body, two chief varieties of phago- cytes are present: (a) The microphages, which are the polymorpho- nuclear leukocytes of the blood, and (b) the macrophages, which include the large mononuclear leukocytes, the fixed connective tissue cells, and other cells possessing phagocytic properties. The micro- phages exert a special digestive action on bacteria, while the macro- phages possess special activity toward animal cells and protozoa. When the digestive ferment of the microphages, the microcytase, is given off by the cells and is circulating in the blood, the blood-serum acquires bacteriolytic or cytolytic properties. In insusceptible or immunized animals the specific bacteria are attracted by the microphages and ingested and digested. However, before the digestion of the bacteria can take place, they must undergo certain alteration, and this is accomplished by a specific substance, also the product of the leukocytes, called fixateur, or fixative, which corresponds to the "immune-body" of the German schools, or the "opsonins" of Wright and Douglas. These opsonins are present in the blood of every individual to a degree proportionate to his resist- ance to a given infection. When infection takes place, the organism 382 TEXT-BOOK OP HYGIENE. is depressed at first, and the opsonins are diminished, or what is called a "negative phase" takes place. As soon as the organism recovers from this primary depression, the opsonins increase, and a "positive phase" is reached. Briefly stated, the process of immunity, according to Metchni- koff, is as follows : — (a) The pathogenic bacteria invade the body. (h) The microphages are attracted to the bacteria and the latter are fixed and ingested. (c) The presence of the bacteria stimulates the production of cytase, which acts on the "sensitized" bacteria, resulting in a com- plete digestion of the latter or bacteriolysis. It will be observed that while Metchnikoff's theory explains immunity against the action of bacteria and toxic cells, it fails to explain antitoxic immunity. The latter is best elucidated by the theory elaborated by Ehrlich and his followers. 2. The Lateral-cliain Theory. — According to this theory, the ani- mal cell is made up of numerous bio-chemical atom-groups, the so- called biogen molecules. These groups possess specific affinities for similar groups in either food or other organic molecules. These atom-groups or side-chains in the cell are called receptors, while the corresponding groups in the food-molecule are called haptophores (from the Greek airreiv, to touch, and 4*^puv, to bring). In the process of nutrition, the receptors unite with the haptophores of the food- molecule, and thus the latter becomes an integral part of the cell. With food-molecules of a more complex composition, the process is somewhat different. Here the food-molecule cannot enter into com- bination with the receptor of the cell unless it is in some way modi- fied. This modification or elaboration of the complex food-molecule is accomplished by receptors possessing two different atom-groups. One atom-group possesses an affinity for a ferment-like substance present in the blood-plasma — complement — which prepares the food- molecule, which then combines with the other atom-group. Eecep- tors possessing two such atom-groups are called amhoceptors. Extending this h5q)othesis to the explanation of immunity, we assume that a molecule of bacterial toxin behaves toward the cell very much like a food-molecule, with this difference: A toxin molecule possesses two atom-groups, a haptophorous group, which combines with the receptors of the cell, and a toxophorous group, which exerts a poisonous effect on the cell. If the amount of toxin is not sufficient to destroy the cell, the latter is stimulated to an over-production of THEORIES OF IMMUNITY. 383 receptors, which are cast off and circulate freely in the blood. These free receptors anchor the toxin molecules as soon as they enter the circulation, and thus prevent their combining with the cells. In this manner antitoxic immunity is established and maintained. In the light of this hypothesis, antitoxin is blood-serum containing free receptors, and by its introduction into tlie system in cases of infec- tion (diphtheria, tetanus) we administer free receptors, which cir- culate in the blood and anchor the toxin molecules, which are thus neutralized before they can combine with the cells. The immunity produced by the injection of antitoxin is called passive, and is espe- cially characterized by its short duration, contrasting with the lasting imimunity produced in the body of an individual who overcomes suc- cessfully the infection. In the case of the more complex bacterial bodies or toxic foreign cells, the amboceptors are the protective agents. Here, while one atom-group combines with the complement which fixes the bacteria, or the cells, the other destroys them. As a resuH of immunization or natural infection the amboceptors are produced in excess, ard the free amboceptors circulate in the blood, rendering it bactericidal or cytolytic, as the case may be. QUESTIONS TO CHAPTER XV. ft THE GERM THEORY OF DISEASE. What is meant by the germ theory of disease? When did this doctrine first take definite shape? When was it first clearly enunciated, and by whom? What basis was there then for it? What subsequent evidence soon developed ? What was the first evidence of the parasitic nature of general diseases? Who discovered and who first demonstrated the true cause of anthrax? Who proved tuberculosis to be of microbic origin? When? What other diseases are now known to be caused by specific micro-organisms? What others are probably due to a like cause? What eflfeet has the establishing of the germ theory upon preventive medicine? What is meant by protective inoculation? What evidence is there that this is possible? How do disease germs produce their characteristic effects upon the system? How may the inoculating material be prepared? How is diphtheria antitoxin prepared? How do antitoxins act? What are "opsonins"? What is the "opsonic index"? Define immunity. Name varieties of immunity. What factors are re- quisite to the production of an infectious disease? How is the virulence of a micro-organism increased? How may the resistance of the individual be diminished? How may infection be prevented? Name the accepted theories of immunity. Describe Metchnikoff"s theory. Define cytases, microphages, macrophages; what are their respective functions? WTiat are receptors? How is nutrition of the cell brought about? How do toxins combine with the cell? What is the function of amboceptors? What role do the receptors play in immunity? Wliat is the difference in the mode of action of receptors and amboceptors ? (384) CHAPTER XVI. CONTAGION AND INFECTION. The adjectives "contagious" and "infectious" are used to desig- nate certain diseases which are propagated by immediate contact, or through the intervention of some other medium, from the sick to the healthy. The matters in which reside the morbific power are micro-organisms. The differentiation between contagion and infection is not easy. Many of the diseases commonly called contagious are also infectious; that is, they are propagated not merely by direct contact, but also by air, water, or food which may have become infected with the mor- bific agent. Syphilis, for example, may be regarded as simply a con- tagious disease; at the present day, at least, we cannot conceive of syphilis to be propagated by breathing infected air or drinking water contaminated with the poison of syphilis. Cholera and typhoid fever, on the other hand, are examples of infectious diseases, neither of them being directly contagious, but conveyed from sick to well through the medium of contaminated water, or food. Between these two stand small-pox and typhus fever (and perhaps the other exanthemata), which are not merely contagious, but infectious also. The contagious and infectious diseases are of particular interest to sanitarians, because it is believed that by judicious carrying out of sanitary measures they can be prevented. Hence they are some- times termed preventable diseases. Another peculiarity of the infec- tious diseases is that they usually occur in groups of cases. Thus, small-pox, measles, scarlet fever, typhus fever, diphtheria, and others of the class do not occur sporadically, as it is termed ; that is to say, it rarely happens that only one case of small-pox is observed in a locality, unless active measures are at once taken to stamp it out. Usually a number of cases occur successively, and in most instances the succeeding cases can be traced ultimately to the first case. Contagious and infectious diseases frequently appear as epidemics. Authorities differ as to the proper definition of an epidemic; that is, given the population of a place, how many cases of an infectious or contagious disease are necessary before the disease can be considered epidemic at such place. Tlie following formula was given by the 25 (385) 386 TEXT-BOOK OF HYGIENE. New Orleans Medical and Surgical Association in response to the query: "Under what circumstances is it proper to declare such dis- eases (diphtheria, scarlet fever, measles, small-pox, yellow fever, etc.) epidemic in a place?" The answer given is that the disease should be declared epidemic when the number of cases should reach these proportions^ : — For a population of 100 500 5 per cent. 4 " " 2,000 to 5,000 . 221/2 " thousand. 6,000 to 10,000 . 16 20,000 to 50,000 . 8 " ten thousand 50,000 to 100,000 . 4 " " 200,000 1 " " A disease is said to be pandemic when it spreads rapidly over a great extent of country, and endemic when it is constantly present in a place. Diseases which may be prevalent in certain localities, i.e., endemic, not infrequently spread over larger areas of country — over- flow their borders, as it were — and become epidemic or pandemic. Thus cholera, which is endemic in certain districts of India, fre- quently spreads over adjacent territory, and at times the epidemic wave, as it has been called, rolls over nearly the whole world. Plague, malarial and yellow fevers make similar epidemic excursions into other countries, or sections of country, at a distance from the places where they are endemic. Contagious and infectious diseases possess another peculiarity in that a certain time is required after the introduction of the poison into the system before the disease manifests itself by its typical symp- toms. This is called the "stage of incubation," and varies for dif- ferent diseases. The following table shows the stage of incubation of a number of such diseases : — Table LVI. Incubation of Infectious Diseases. Measles 10 days. Small-pox 12 " Mumps 18 " Diphtheria 3 " Scarlet fever 3 " Whooping-cough • . • • 14 " Typhoid fever 14 " Typhus fever 1 to 2 " Chicken-pox 4 " Erysipelas 4 " 1 Public Health, vol. vi, p. 416, 417. THE CARRIERS OF INFECTION. 387 The period during which the infectiveness of the patient lasts also varies. In some cases it probably depends upon the measures taken to prevent the spread of the disease, e.g., disinfection of the patient and his surroundings. The London Clinical Society has made public a report by one of its committees, which has for several years carefully studied the ques- tions of incubation and the duration of infection. The conclusions reached do not differ essentially from those in the above table, but as they are given somewhat more in detail they are here appended : — Diphtheria, two to seven days; oftenest two. Typhoid fever, eight to fourteen days; sometimes twenty-three. Influenza, one to four days; oftenest three to four. Measles, seven to eighteen days; oftenest fourteen. Mumps, two to three weeks; oftenest three weeks. Eubeola, two to three weeks. Scarlet fever, one to seven days; oftenest two to four. Small-pox, nine to fifteen days; oftenest twelve. Further investigations were made with regard to the time and duration of the infective period. Diphtheria was found to be infective during the period of incu- bation, attack, and convalescence. Mumps and rubeola are also infective for three or four days before the onset of the parotiditis and appearance of the rash. The contagiousness of measles speedily disappears, and does not continue in disinfected persons for over three weeks. Typhoid fever is infectious from the time of onset until two weeks after the fever has gone and convalescence set in. As is well known, the contagiousness of scarlet fever varies greatly, but is generally continued a very long time — certainly until desquamation ceases, and sometimes as long as eight weeks. THE CARRIERS OF INFECTION. The germs of infectious or contagious diseases may be conveyed either by inanimate objects which come in contact with the original source of the disease or by living animals. Of the former, air, food, water, and clothing, the latter included under the general term "fomites," have already been discussed. The transmission of disease by animals, especially by insects, is a subject which has assumed con- siderable importance of late. Leaving aside the strictly animal dis- eases which are communicable to man, as anthrax, glanders, hydro- phobia, actinomycosis, etc., we will consider only the instances in 388 TEXT-BOOK OF HYGIENE. which the animal acts as a passive agent, or an intermediary host. Thus, oysters from sewage-polluted beds have been responsible for epidemics of typhoid fever. The bacillus coli has been found in the bodies of such oysters, while Chantemesse and others have demon- strated the possibility of oysters carrying the typhoid bacillus. Certain snails appear to be intermediate hosts for worms parasitic to man. The most important disease-carriers, however, are the insects. These may either convey the germs mechanically, or inoculate them by stinging or biting, or act as intermediate hosts. Thus, flies may carry on their legs or within their bodies the germs of cholera, typhoid fever, tuber- culosis, and other infectious diseases, and deposit them on the food or drink which is subsequently consumed by man. There is abundant evidence to prove that in many instances epidemics of typhoid fever have been caused through the agency of the domestic fly. During the Spanish-American War several camps were visited by epidemics of typhoid fever, and in every instance flies were demonstrated as the carriers of the infection. Fleas, bed-bugs, spiders, and lice may and often do transmit disease by biting the individual and inoculating the wound with the bacteria which are present on the proboscis. In the case of mosquitoes, there are certain species which act as the intermediary host and are essential factors in the propagation of disease. Thus, the plasmodium malarias, a pro- tozoon which is the specific cause of that disease, undergoes two cycles of development: an asexual cycle in the human body, and a sexual cycle in the body of the mosquito of the genus anopheles. When the mosquito draws the blood from a person suffering from malaria, the flagellate forms of the parasite (microgametocytes) are developed in its stomach. The flagella (microgametes, or male ele- ments) are discharged, move towards other non-flagellated forms of the parasite (macrogametes, or female elements) and fertilize them, The fertilized parasites then invade the intestinal wall and form a cystic structure (oocysts), containing numerous minute rods or sporo- zooits which have resulted from the segmentation of the parasite. The oocysts eventually rupture and the sporozooits find their way into the veneno-salivary glands of the mosquito, to be introduced into the next person who is so unfortunate as to receive the sting of the infected mosquito. Once in the circulation of man, the parasites in- vade the red blood-cells and there undergo multiplication by segmen- tation. Eecently it has been demonstrated that yellow fever is transmitted by another species of mosquito, stegomyia fasciata, probably in a simi- THE CARRIERS OF INFECTION. 389 lar manner; while Manson has shown that the mosquito (culex) acts as the intermediary host of the parasite of elephantiasis (filaria sanguinis hominis) . Of the higher animals, rats have been shown to be the carriers of bubonic plague, a disease to which they are subject. The prophylaxis of diseases transmitted by insects and the higher animals is to be accomplished by cleanliness, destruction of the pests whenever possible, and avoidance of contact with animals harboring the germs of disease. QUESTIONS TO CHAPTER XVI. CONTAGION AND INFECTION. ' What is the difference between a contagious and an infectious disease? Give examples of each. What diseases do not belong to either of these classes? What other names might be given to contagious and infectious diseases? How do they usually occur? What are their exciting causes? How may they be prevented ? What is an epidemic? When may a disease be declared epidemic in a city of 10,000 persons? Wlien is a disease pandemic? When endemic? May an endemic disease become epidemic or pandemic? What other peculiarities do contagious and infectious diseases possess? What diseases have the longest period of incubation? What ones the shortest? How does the period of incubation support the germ theory? What other definite period has each of these diseases? What is the usual duration of a case of typhoid fever? Of scarlet fever? Of measles? Does this support the germ theorj^? How long does a typhoid patient remain infective? How long a diphtheria patient? A scarlet-fever patient? (See chapters on School Hy- giene and Quarantine.) Upon what does the danger and period of infective- ness depend? Are these diseases all likely to confer immunity against future attacks? Which are most likely to do this? What role do animals play in the transmission of disease? Name insects which act as intermediate hosts in the transmission of malaria. Of yellow fever. Describe the mode of transmission of malaria by the mosquito. (390) CHAPTER XVII. HISTORY OF EPIDEMIC DISEASES. An important part of the knowledge of the sanitarian is that which relates to the history of the great epidemic diseases which have at various periods devastated large areas of the inhabited world. In this chapter the history of these diseases will be briefly traced. Al- though some of these diseases have nearly or quite ceased, a knowledge of their habits and of the causes that finally led to their extinction is of great value, for the reason that the principles and measures of prevention which were effective in times past are the same which must apply at present and in the future. Hence, time spent in look- ing back over the fields traversed and noting victories won will not be wasted. The epidemic diseases which will here claim attention are the Oriental plague, the sweating sickness, small-pox, Asiatic cholera; typhus, typhoid, scarlet, relapsing, and yellow fevers; diphtheria, dengue, epidemic influenza, and syphilis. In addition, some informa- tion will be given on certain of the diseases of animals transmissible to man. Among these are sheep-pock, actinomycosis, bovine tuber- culosis (perlsucht), rabies, anthrax (milzbrand), and glanders. THE ORIENTAL PLAGUE. The Oriental plague, bubonic plague, the black death, or simply the '^plague," or great pestilence, overtopping in its fatality all other pestilences, is mentioned by a number of the Greek and Latin medical authors. The first account which clearly refers only to this disease is given by Procopius. According to this and other contemporary authors, the disease began to spread in the year 542 from Lower Egypt, passing in one direction along the coast of Northern Africa. and in the other invading Europe by way of Syria and Palestine. In the course of the succeeding years this pandemic reached "the limits of the inhabited earth," in the language of the writers of the day. The disease prevailed about half a century, and produced the greatest devastation wherever it appeared. "Cities were devastated, the country converted into a desert, and the wild beasts found an asylum in the abandoned haunts of man."^ ^ Warnefricfl, quoted by Hirsch, Hist-Geographische Pathologie, I, p. 350. (391) 392 TEXT-BOOK OF HYGIENE. The plague is an acute infectious disease caused by a bacillus {iacillus pestis) and characterized by an affection of the Ij^mphatic system, i.e., inflammation and swelling of the external and internal IjTuphatic glands. Accessory symptoms are petechial spots upon the skin, and hemorrhages from various organs, as the stomach, nose, kidneys, rectum, and uterus. Those attacked suffer in varied degrees of intensity. In some, a fulminant form occurs which carries off the patient within three days ; there is another class of cases in which buboes develop, with accompanying fever and hemorrhages; and finall}', a light form, rarely fatal, in which only the local symptoms are manifested. In the great pandemic plague of the fourteenth cen- tury cough and bloody expectorations were very frequent. In the later epidemics hemorrhage from the lungs has been rarely noticed as a s}Tnptom. About the middle of the fourteenth century the bubonic plague made a second incursion into Europe from its home in the East. A most graphic description of its ravages is given by Boccaccio in the "Decameron." This author states that in 1359, 'iDctween March and July following, according to authentic reckonings, upward of 100,000 souls perished in the city (Florence) ; whereas, before that calamity it was not supposed to contain so many inhabitants." This terrible epidemic was forcibly characterized by its com- mon name, "the black death." Hecker estimates that during its con- tinuance, from 1347 to 1351, 25,000,000 — one-fourth of the probable total population of Europe — died. In various cities the mortality was —in London, 100,000; in Paris, 50,000; in Venice, 100,000; in Avignon, 60,000; in Marseilles, 16,000, in one month. It was said that in all England scarcely a tenth part of the population escaped death from the disease. The moral effects of this great pandemic of the plague were hardly less deplorable than the physical. Eeligious fanaticism held full sway throughout Europe, finding its vent in all manner of ex- cesses. The so-called Brotherhood of the Cross, otherwise known as the Order of Flagellants, which had arisen in the thirteenth ceutury, but had been suppressed by the ecclesiastical authorities, was revived during the black pestilence, and large numbers of these religious enthusiasts roamed through the various countries on their great pil- grimages. Their power increased to such a degree that Church and State were forced to combine for their suppression. One consequence of this fanatical frenzy was the persecution of the Jews. These were accused of being the cause of every evil that befell mankind, and many were put to death. THE ORIENTAL PLAGUE. 393 In the fifteenth and sixteenth centuries the plague was generally diffused throughout Europe, and in the second third of the seventeenth century its final incursion into the Occident took place. The great epidemic in London, so graphically described by Defoe,^ occurred in 1665. In the early part of the eighteenth century (1720) the plague visited Marseilles and Toulon ; from 1769 to 1773 it was epidemic in Moldavia, \Yallachia, Poland, and Southern Kussia; near the close of the eighteenth and in the beginning of the nineteenth century, in Transylvania, Wallachia, Southern Eussia, and Greece. In 1878 and 1879, and in 1885, the plague threatened a new irruption into European territory, being epidemic in the district of Astrachan, on the Caspian Sea. In 1894 it was reported epidemic in certain parts of China. Although the bubonic plague has never been observed in America in epidemic form, and has spared Enrope almost entirely during the present century, it still persists in certain countries of Asia and Africa, especially in Arabia, Mesopotamia, Persia, and the coast of Tripoli. A number of cases of plague occurred a few years ago in San Francisco, in the Chinese quarters. The older authors ascribed the origin of the plague to various real or supposed conditions. Comets, conjunctions of the planets, "God's just punishment for our sins," and similar causes were advanced to account for the outbreaks. Most of the writers of the post-medieval and modern epochs ascribed the disease to meteorological conditions. Observing the fact that the plague never advanced into the torrid zone, and that an epidemic generally ended with the advent of hot weather, a high temperature v;as believed to be incompatible with the existence of an epidemic, and a cold or temperate climate was con- sidered necessary to an outbreak of the disease. The exceptions to the rule are so numerous, however, that the theory of the climatic or meteorological origin of the plague failed of support. The theory which ascribed the origin of the epidemics to the influence of cer- tain hot and dry winds or a high humidity is also insufficient. Cer- tain geological formations have been supposed to furnish favorable conditions for the development of the disease. Facts show, however, that the disease has prevailed epidemically and endemically in vari- ous parts of the earth, and of the most diverse geological character. A certain elevation above sea-level has been held to confer immunity, but recent observations in India show that this belief is unfounded. Journal of the Plague in London. 394 TEXT-BOOK OF HYGIENE. even places at an elevation of 10,000 feet above sea-level giving no security against attack. There is, however, one point upon which nearly all writers who mention the fact at all agree. That is that bad hygienic conditions are always present where plague prevails. Nearly all observers who have left their impressions on record mention the accumulation of filth in the houses and streets, deficient removal of excrementitious and other sewage matters, crowding and imperfect ventilation of dwellings as causes favoring the development and spread of the pes- tilence. All point out the necessity of the removal of these evils as the most important prophylactic measure to be adopted, and all of them call attention to the fact that those classes of the population most exposed to these unfavorable influences suffer most from the violence of the epidemic. The later reports of the epidemics in Persia, India, Mesopotamia, and Eussia agree in asserting that nothing seems to have promoted the epidemic and endemic prevalence of the plague so much as the material wretchedness of the inhabitants of those countries. In a collection of papers on the plague, printed by a British Parliamentary Commission in 1879, occur these statements: "The filth is every- where," says Mr. Eennie, one of the reporters — "in their villages, their houses, and their persons. Their dwellings are generally low and ill- ventilated, except through their bad construction; and the advan- tage of the natives in other parts of India, of living in the open air, is lost to the villagers of Ghurwal, from the necessity of their crowd- ing together for mutual warmth and shelter against the inclemency of the weather." Dr. Dickson, reporting on the plague in Irak Arabi, in 1876, saj^s: "The most palpable and evident of all the causes which predispose an individual to an attack of plague during an epidemic outbreak is poverty. No other m^alady shows the influence of this factor in so striking a degree; so much so, indeed, that Dr. Cabiadis styles the plague miserice morhis. In his experience (1876- 77, in Bagdad) he found that the poor were seldom spared, the wealthy hardly ever attacked."^ The manner of the transmission of the plague has now been dis- covered to be by infected rats and fleas. Hence, it may be termed an infectious disease, although it is not improbable that it may be com- municated by direct contact both of persons and of fomites. These considerations indicate the measures of prevention to be *Hirsch, op. cit., p. 370. THE SWEATING SICKNESS. 395 adopted. They consist of a rigid quarantine of persons and fomites, prompt and complete isolation of infected individuals and localities, and destruction (by fire) or thorough disinfection by steam or sul- phurous-acid gas of all materials capable of conveying the virus of the disease, and especially the destruction of rats. THE SWEATING SICKNESS. This name concisely characterizes an epidemic disease which for the first time appeared in the city of London and other parts of England in the autumn of 1485. According to Lord Bacon/ the disease began about the 21st of September and lasted until near the end of October. It broke out a second time in the summer of 1507; a third time in July, 1518, spreading in the course of six months throughout England. In May, 1529, the disease made its appearance again in the latter country, spreading thence over a great part of the continent of Europe. Another very malignant epidemic broke out in the spring of 1541, lasting through the summer, and limited in its ravages to England. With this outbreak, in 1551, this disease disappeared entirely in England, and has not re-appeared there up to the present day. In the beginning of the eighteenth century, however, a disease very similar in its symptoms and course broke out in Picardy and other districts of Northern France, being confined for a number of years to this sec- tion of the country. Toward the end of the century it spread to the south of France, and since that time has appeared epidemically at intervals, 195 distinct outbreaks having been observed in the course of 168 years, from 1718 to 1887. The disease has frequently appeared in Italy since 1755, and in various parts of Germany since 1801. In Belgium it has been observed at a few places within the present century. The disease appeared suddenly, often at night-time. The patient was attacked with palpitation of the heart, dyspnea, great anxiety and oppression, and profuse perspiration. A miliary eruption often ap- peared on the skin. In favorable cases these symptoms diminished in the course of one or two days, the urinary secretion, which had been suppressed, was restored, and the perspiration became gradually less free. Recovery ensued in from one to two weeks. In grave cases there were, in the beginning of the attack, violent headache, delirium, * History of Henry VII. 396 TEXT-BOOK OF HYGIENE. convulsions, followed by a comatose condition, from which the patients rarely recovered. This disease is undoubtedly of an infectious nature, as proved by its raipid spread and limitation to certain localities. It appears most frequently in the spring and summer, and is nearly always observed in marshy or damp localities. Its spread is favored by a high tempera- ture and humidity. There is no apparent connection between the outbreaks of the sweating sickness and overcrowding or other unsani- tary conditions; in fact, it is stated by numerous observers, both old and recent, that children, the aged, and generally the poorer classes were remarkably exempt from the disease. The recent epidemic in France, in 1887, was investigated by Dr. Brouardel, Chanteraesse, and other epidemiologists, but no trustAvorthy conclusions as to the nature of the disease have yet been reached. Since the first appearance of Asiatic cholera in France, in 1833, an apparently intimate connection has been observed between the oc- currences of that disease and outbreaks of sweating sickness. A disease strongly resembling the sweating sickness has also been ob- served in India in districts contiguous to places where cholera was at the time epidemic.^ SMALL=POX. The earliest details concerning small-pox are derived from cer- tain Chinese records, according to which it appears that this disease was known in China upward of 2000 years ago. It was also known at a very early period in India. It is believed to have been introduced into Europe in the second century by a Eoman army returning from Asia. It is believed that the Emperor Aurelius died of small-pox, which prevailed in his army at the time of his death. The first distinct references to small-pox in medical literature occur in the writings of Galen, in the second century. Ehazes, in the ninth century, wrote upon the disease, describing it very accurately. The almost universal susceptibility to small-pox caused wide- spread devastation wherever it appeared previous to the introduction of vaccination. The statement is made that in England, in the last century, about one person in every three was badly pock-marked. The mortality from the disease was exceedingly great, being, in the latter half of the eighteenth century, about 3000 per million of inhabitants annually. 5 Murray, Madras Quart. Med. Journ., 1840-41. Quoted in Hirsch, loc. cit., p. 83. SMALL-POX. S97 In India tlife mortality from small-pox has been exceedingly great within the last twenty years. From 1866 to 1869, 140,000 persons died in the Presidencies of Bombay and Calcutta, having a population of about 40,000,000. Several years later, from 1873 to 1876, 700,000 died from this disease. China, Japan, Cochin China, the islands of the China Sea, and Corea are frequently ravaged by small-pox. In the latter country nearly all the inhabitants are said to bear evidence of an attack of the disease. The Samoyedes, Ostiaks, and other natives of Eastern Siberia have frequently suffered from devastating epidemics. In Kamtchatka the disease was introduced in 1767 and produced frightful ravages. Many villages were completely depopulated. In Mexico small-pox was introduced by the Spaniards in 1520. In a short time it carried ofE over 3,500,000 of the natives. In the Marquesas Islands one-fourth of the inhabitants have fallen victims to the disease since 1863. . It was first introduced into the Sandwich Islands in 1853, and carried off 8 per cent, of the natives. Australia, Tasmania, New Zealand, and the Fejee Archipelago remain exempt to the present day from small-pox. It has several times been carried to Australia by vessels, but has always been promptly checked by the vigilance of the authorities. On the Western Hemisphere small-pox was unknown before the arrival of the European conquerors. It has been spread by the whites or imported African slaves to nearly all the Indian tribes of both continents. When it attacks large communities unprotected by pre- vious outbreaks of the disease, or by inoculation or vaccination, its ravages are frightful. The mortality of " unmodified small-pox , is usually between 30 and 40 per cent. Small-pox is a highly contagious and infectious disease. It is produced by actual contact, by inoculation, and by inhaling an at- mosphere charged with the poison. In order to cause an outbreak two factors are necessary.: first, a number, of individuals susceptible to the disease, and, second, the introduction into the body in some manner, of the virus upon which it depends. Small-pox is spread from (1) persons sick with the disease; (3)' others, not themselves sick or susceptible, but coming in contact with the poison; (3) fomites (cotton, wool, etc.), and (4) the bodies of persons dead with small-pox. It is also probable that the air in the 39g TEXT-BOOK OF HYGIENE. immediate vicinity of a person sick with small-pox becomes charged with the poison and able to convey the disease. It is at present impos- sible to fix the distance to which this infectiousness of the air ex- tends, but it does not ordinarily reach beyond the room in which the patient is confined. It is a fact of common observation that the darker races are more commonly attacked, and the disease is likewise more fatal among them. The mortality among negroes is much larger than among other races. It is a current belief that small-pox is only contagious after the development of the pustules. This is a serious error. It is probably contagious in all stages of the disease; certainly as early as the first appearance of the eruption, and probably even in the stage of prelim- inary fever. One attack of small-pox usually confers immunity from the dis- ease for life. This rule has its exceptions, however, which, if not numerous, are yet not infrequent. The author has seen a case in which the patient suffered from a third attack of the disease. The popular belief, that persons suffering from any acute or chronic disease are less liable to be attacked by small-pox than those at the time in good health, is erroneous. On the contrary, the subjects of chronic disease, such as consumption or dyspepsia, are much more liable to succumb to an attack of small-pox than persons previously in good health. It is true, however, that individuals suffering from some other acute infectious disease, like scarlet fever, measles, typhoid fever, etc., are generally, though not absolutely, exempt from an attack of small-pox during the time they are sick with such disease. But if they are exposed, after recovery, to the small-pox infection, their liability to an attack is as great as in those who have not passed through a similar disease. A number of cases have been reported by Curschmann,^ in which infection by small-pox took place on the day in which convalescence from typhoid fever was established. The author has reported a case'' in which the patient passed through an attack of erysipelas during the incubative stage of small- pox. From all the evidence attainable, the incubative stage was not prolonged by the intercurrent erysipelas. Epidemics of small-pox usually begin in the autumn or winter, and lessen in violence as warmer weather approaches. The spread 'Ziemssen's Cyelopoedia, vol. ii. Medical News, July 7, 1883. SMALL-POX. 399 of the disease is slow at first, increasing in rapidity as the foci of infection multiply. When the poison is imported into a community late in the spring or during the summer, the increase in the number of cases is ex- ceedingly gradual until colder weather sets in. If it is introduced dur- ing the winter, the disease spreads much more rapidly, but decreases. and sometimes almost disappears, during the summer. On the return of cold weather, however, the epidemic starts out with a new lease of activity and presents great difficulties to its restriction. A number of observers, among whom are Coze and Feltz, Lugen- biihl, Weigert, Strauss, Garre, and Wolff, claim to have discovered specific organisms in the contents of variolous pustules, in the blood of patients with the disease, and in vaccine lymph. Expert bacterio- logists are, however, not willing to accept the evidence hitherto fur- nished as conclusive. Inoculation. — The prevention or restriction of such a universal and fatal pestilence as small-pox is a matter of the deepest impor- tance. The first attempt to limit its fatality dates from the end of the seventeenth century. It became generally known in Europe, about the year 1700, that tlie intentional inoculation of variolous matter into healthy individuals induced an attack of the disease, which generally ran through its various stages with less virulence than when the disease was contracted in the usual manner. In 1716 and 1717 two papers were published in the "Transactions of the Eoyal Society of England" giving an account of the process of inoculation. The at- tention of the public was especially directed to the matter, however, by the famous letter of Lady Mary Wortley Montagu, dated April 1, 1717. This letter is as follows^: "Apropos of distempers, I am going to tell you a thing that will make you wish yourself here. The small-pox, so fatal and so general amongst us, is here entirely harm- less by the invention of ingrafting, which is the term they give it. There is a set of old women who make it their business to perform the operation every autumn, in the month of September, when the great heat is abated. People send to one another to know if any of their family has a mind to have the small-pox ; they make parties for this purpose, and when they are met — commonly fifteen or sixteen together — the old woman comes with a nut-shell full of the matter of the best sort of small-pox, and asks what veins you please to have opened. She immediately rips open that you offer to her with a large needle — which gives you no more pain than a common scratch — and *The letter is addressed to Mrs. S. C. (Sarah Chiswell). 400 TEXT-BOOK OF HYGIENE. puts into the vein as much matter as can lie upon the head of her needle, and after that binds up the little wound with a hollow bit of shell ; and in this manner opens four or five veins. The Grecians have commonly the superstition of opening one in the middle of the forehead, one in each arm, and one on the breast, to make the sign of the cross; but this has a very ill efEect, all these wounds leaving little scars, and is not done by those that are not superstitious, who choose to have them in the leg or that part of the arm that is con- cealed. The children or young patients play together all the rest of the day, and are in perfect health until the eighth. Then the fever begins to seize them, and they keep their beds two days, very seldom three. They have rarely above twenty or thirty in their faces, which never mark; and in eight days' time they are as well as before their illness. Where they are wounded there remain running sores during the distemper, which I don't doubt is a great relief to it. Every year thousands undergo this operation; and the French ambassador says pleasantly: 'They take the small-pox here by way of diversion, as they take the waters in other countries.' There is no example of any one that has died in it, and you may believe that I am well satisfied of the safety of the experiment, since I intend to try it on my dear little son. "I am patriot enough to take pains to bring this useful invention into fashion in England ; and I should not fail to write to some of our doctors very particularly about it, if I knew any of them that I thought had virtue enough to destroy such a considerable branch of their revenue for the good of mankind. But that distemper is too beneficial to them not to expose to all their resentment the hardy wight that should undertake to put an end to it. Perhaps, if I re- turn, I may, however, have courage to war with them." Soon after the date of this letter the writer's son was inoculated in Turkey, and four years later her daughter also, being the first sub- ject inoculated in England. The practice soon became popular, but several fatal cases among prominent families brought it into disrepute, and for about twenty years very few inoculations were made in Eng- land. It was revived about the middle of the century by the founding of a small-pox and inoculation hospital in London. This continued in operation until 1832. The records of this institution showed that only three in a thousand died of the disease thus communicated. The practice has now fallen into desuetude, being superseded by vaccina- tion and prohibited by law in England. Inoculation was introduced into this country in 1721 by Dr. Zab- SMALL-POX. 401 diel Boylston, of Boston, who had his attention directed to the prac- tice by Cotton Mather, the eminent divine." During 1721 and 1722, 286 persons were inoculated by Boylston and others in Massachu- setts, and 6 died. These fatal results rendered the practice unpopular, and at one time the inoculation hospital in Boston was closed by order of the Legislature. Toward the end of the century an inoculat- ing hospital was again opened in that city. Early in the eighteenth century inoculation was extensively practiced by Dr. Adam Thomson, of Maryland, who was instrumental in spreading a knowledge of the practice throughout the Middle States.^" In China and India, and perhaps other eastern countries, inocu- lation was practiced at a very early period. The inoculation of variolous matter, although it mitigated to a very great degree the attack of small-pox following, had one very serious objection, aside from the small death-rate which was a direct consequence of it. This was the fact that inoculation always pro- duced small-pox, and thus assisted in propagating the disease; for. however mild the induced disease might be, the inoculated individual was liable to communicate small-pox to others in the most virulent form. Hence, nothing short of universal inoculation, which was mani- festly impracticable, would succeed in reducing the danger from the disease. Vaccination. — It had been noticed at various times that a pus- tular disease which sometimes appears on the udders of cows, called cow-pox, had not infrequently been transmitted to the hands of the dairy-maids and others having much to do with cows. In the course of time it was also noticed that persons who had been thus attacked never suffered from small-pox. This protective power of cow-pox was known as early as 1713, and in 1774 Benjamin Jesty, a Gloucestershire farmer, performed vaccination for the first time on record, inoculating his wife and two sons with cow-pox matter as a protection against small-pox. It is said that when it became known that Jesty had vaccinated his wife and sons, "his friends and neighbors, who had hitherto looked upon him with respect, on account of his superior intelligence and honorable character, began to regard him as an inhuman brute, who "Dr. John T?. Quinan (Md. Med. Journ., June 23 and 30, 1883) believes the claim of Dr. Boylston to be the first American inoculator open to ques- tion. The evidence presented is, however, insufficient to discredit the claim of the Boston physician. ""See Quinan, loc. cit., p. 114. 26 402 TEXT -BOOK OF HYGIENE. could dare to practice experiments upon his family, the sequel of which would be^ as they thought, their metamorphosis into horned beasts. Consequently the worthy farmer was hooted at> reviled, and pelted whenever he attended the markets in his neighborhood."^^ In 1791 a school teacher in Holstein also inoculated three boys with the matter of cow-pox, but nothing is known of the subsequent history of these cases. Although the above facts are clearly established, it is to Edward Jenner, a modest country doctor of Berkeley, in the county of Glou- cester, England, that the merit of demonstrating the protective power of cow-pox against small-pox, and of diffusing a knowledge of this fact, is due. Jenner had his attention directed to the asserted pro- tection conferred by cow-pox during the period of his apprentice- ship. After a residence in London as a pupil of John Hunter, he returned to the country to practice his profession. About the year 1776 he began studying the question, and gathering evidence of the protection afforded against small-pox by the accidental inoculation of cow-pox virus. For twenty years he studied the subject, patiently awaiting an opportunity to put his belief to the test of experiment. On the 14th of May, 1796, he made his first vaccination on a boy named James Phipps. Six weeks later he inoculated this boy with variolous matter, but without success, no small-pox resulting. Two years later he published his pamphlet, entitled "An Inquiry into the Causes and Effects of the Variola Vaccinae," etc., in which he detailed his observations and experiments. This publication produced a great sensation in the medical world, and, although much opposition was at first manifested towards his views, he soon gained many adherents. Vaccination, as the operation for the inoculation of cow-pox virus is termed, was rapidly introduced into all civilized countries, and soon demonstrated its good effects by greatly restricting the prevalence of small-pox. It is generally believed that the first one to practice vac- cination in this country was Dr. Benjamin Waterhouse, of Boston, in the summer of 1800; but Dr. John E. Quinan has recently shown^^ that vaccination was introduced into Maryland, by Dr. John Craw- ford and Dr. James Smith, at least as early as the date generally as- signed for its introduction into Massachusetts. It was believed by Dr. Jenner, and afterward conclusively shown by a number of distinguished experimenters, that vaccinia, as the dis- ease produced by cow-pox inoculation was called, was merely a modi- " London Lancet, September 13, 1862. ^Quinan, Joe. cit., pp. 118, 131. SMALL-POX. 403 fication of small-pox as it existed in the cow. Small-pox virus, when inoculated upon the cow, produced cow-pox; but the latter, re-inocu- lated upon man, produced cow-pox (vaccinia), and not small-pox. These experiments, however, have not been successful in all instances, and the identity of the two diseases, while generally recognized, is not absolutely established. Sheep-pock and horse-pock, or "grease," are probably merely modifications of the disease produced by inocu- lating small-pox into those animals. When cow-pox virus is successfully inoculated into the human system — that is, when a person is successfully vaccinated — the fol- lowing local and general symptoms are observed : — In the case of a primary vaccination, i.e., where the individual has not been previously vaccinated or attacked by small-pox, the point where the vaccination is made shows no particular change for the first two days. If the vaccination is successful, a small, reddish pap- ule appears by the third day, which, by the fifth or sixth day, has be- come a distinct vesicle of a bluish-white color, with a raised edge and a peculiar, central, cup-like depression called the umbilication. By the eighth day this vesicle has become plump, round, and pearl-col- ored, the central umbilication being still more marked. At this time a red, inflamed circle, called the areola, appears, surrounding the vesicle and extending usually in a radius of from one-half to two inches when fully developed. This inflammatory ring is pretty firm, and there is more or less general fever and often enlargement and tenderness of the axillary glands. After the tenth day the areola begins to fade, and the contents of the vesicle dry into a hard, brown- ish crust or scab, which falls off between the twentieth and twenty- fourth days, leaving a punctated scar, which gradually becomes white. When the vaccinia has passed through all of these stages, espe- cially if the vesicle filled with pearly lymph, and the areola have been well developed, the vaccination may be considered a success, and the individual protected against small-pox for a number of years, if not for life. Eecently the doctrine has been strongly advocated that vac- cination is not absolutely protective until a subsequent inoculation of vaccine fails to "take." According to this view, vaccination should be repeated until it fails any longer to exhibit any local reaction. When this has been attained the individual may be considered abso- lutely protected for life. Theoretically, this view has much in its favor, but there is, as yet, not sufficient evidence to establish it as a law. It may be stated as an established fact that vaccination, although 404 TEXT-BOOK OF HYGIENE. carefully performed and successful, does not confer absolute immu- nity from small-pox for life. The protective power seems to wear out after a time and the individual then again becomes susceptible to small-pox. An attack of small-pox in a vaccinated individual is, however, nearly always much milder than where there had been no vaccination. There is no fact in the entire range of medicine bet- ter established than this: that small-pox in vaccinated persons is a much less dangerous disease than typhoid fever, while in unvaccinated cases the mortality ranges from 30 to 40 per cent. An approximate guide to the beneficent influence of vaccination upon the mortality from small-pox is furnished by a table in Seaton's report on vaccina- tion. Before the introduction of vaccination the mortality from small-pox per million of inhabitants of England, was nearly 3000 per year. After the introduction of vaccination the mortality was re- duced to 310 per million per year. The most remarkable and convincing statistical evidence on the question is given by Drs. Seaton and Buchanan, of England. Dur- ing the small-pox epidemic in London, in 1863, they examined over 50,000 school-children, and found among every thousand without evi- dence of vaccination 360 with scars of small-pox, while of every thousand presenting some evidence of vaccination only 1.78 had any such traces of small-pox to exhibit.^^ The reliability of general mor- tality statistics may be called in question — in some cases, with justice ; but the significance of these figures cannot be evaded. The upper and outer surface of the arm is usually chosen as the point where the virus is inserted, although any part of the body which can be protected against friction, or other mechanical irritation, may be selected. The method varies slightly in the hands of different vaccinators. The two methods most frequently in use are scarifica- tion and erasion. The former method has the indorsement of Mr. Seaton, the high English authority. The method of erasion — scrap- ing off the epidermis until the papillary layer of the skin is laid bare — is now most frequently used in this country. The best instru- ment to use is a clean thumb-lancet; in default of this, an ordinary sewing-needle answers well. Where animal vaccine is used, the ivory slip or sharpened quill may also be used with satisfaction to make the scarification or erasion. Whatever instrument is used, it should always be kept perfectly clean. A point of vital importance is that which relates to the proper "Seaton, "Vaccination," ii Reynold's System of Medicine, vol. i, p. 291. Second edition. SMALL-POX. 405 age at which children should be vaccinated. Ordinarily, vaccina- tion should be performed within the first six months of life. In time of danger from a threatened, or in the presence of an actual, epidemic, infants may be vaccinated when only one day old. In order to secure permanent protection against small-pox, re- vaccination should be performed after a certain interval. Some place the period at which this second vaccination should be done at five years, while others allow a longer interval — seven, eight, or ten years. The law of Prussia is that every child that has not already had small- pox must be vaccinated within the first year of its life, and every pupil in a public or private institution is to be revaccinated during the year in which his or her twelfth birthday occurs. This law was passed in 1874. Prior to this time the mortality from small-pox was 15 to 20 per 100,000 of the population. Since the law was enacted the small-pox mortality has varied from 0.3 to 3.6 per 10,000. Not a single death from small-pox occurred in the German army between 1874 and 1882.^* A revaccination, even if successful, seldom passes through all the typical stages of a primary vaccination. The vesicle rarely becomes so full and plump, and is more frequently flat and irregular in outline. Swelling of the axillary glands and other complications alsQ seem to be more frequent than in cases where the vaccination is done for the first time. The question whether the lymph direct from the cow or human- ized lymph is the more efficient has caused much discussion. The objections urged against the use of humanized virus are : first, that its protective power has become diminished by transmission through many generations; second, that it is liable to transmit other diseases, such as syphilis, tuberculosis, scrofula, etc. ; third, that it is fre- quently difficult to obtain in sufficient quantities in an emergency, such as an actual or threatened epidemic. The first objection is disproved by the testimony of many of the most distinguished medical men in Europe and this country. Hu- manized vaccine virus, when properly inoculated, seems to be as completely protective against small-pox as that taken direct from the animal. Among its advantages are, that it "takes" more readily and runs through its stages of development in a shorter time, and that it will retain its active properties for a greater length of time than animal virus. The physician can usually control the source whence he obtains it. He can watch over the subject that furnishes it '■"rrolich, Militilr-Medicin, p. 461. 406 TEXT-BOOK OF HYGIENE. and reject that which is suspicious. With humanized lymph col- lected by the physician himself there can be no doubt as to its purity or age; with animal Ijonph furnished by the cultivators of that ar- ticle there can be no certainty about either of these important points. That syphilis has been inoculated with humanized virus can no longer be open to doubt. The recent experiment of Dr. Cory, of England, has settled this question definitely. With care, however, this sad accident can easily be avoided, and the fact that syphilis has been so rarely transmitted by vaccination is sufficient evidence that the danger of such infection is not very great. The most serious objection against the exclusive use of human- ized lymph, is, that in grave emergencies, such as a rapidly-spreading epidemic of small-pox, it is difficult to obtain a sufficient supply of the lymph. However, humanized virus can never be obtained under the same strict asepsis as prevails in the production of animal virus, and its employment is not justifiable on this account, if for no other reason. Humanized virus is inoculated, either in the fresh state, i.e., the lymph is taken directly from the vesicle on the seventh day and inoc- ulated directly into the arms of other individuals, or else the vesicle is allowed to dry into a crust, with which a thin paste is made by moistening with water at the time of vaccination. The readiest way of using the crust is to crush a small fragment between two small squares of glass, then moistening it with a drop of warm (not hot) water, and smearing it on the spot where the vaccination is to be made. With a lancet a number of cross-scarifications are then made, and the virus well rubbed in. Only so much of the crust should be moistened as will be used at the time. Particular care must be taken not to use saliva for moistening the crust. Aside from being unclean, there is danger of producing blood-poisoning by inoculating certain of the oral secretions. ^^ Animal virus is obtained by inoculating a calf or heifer with virus from another case of cow-pox, or by re-inoculating humanized vaccine virus into the animal. The vesicles are opened on the sev- enth day or at the end of ninety-six hours (Copemann) and ivory points or the ends of quills coated with the Ijmiph and dried with a gentle heat, or the pulp is rubbed up with 50 per cent, glycerin and drawn up in fine glass tubes. The whole operation, from beginning to end, is done under strict asepsis. In vaccinating with animal virus, the quill or ivory point is first i^See Sternberg and Magnin, Bacteria, p. 355. Second edition. SMALL-POX. 407 moistened with a drop of water to soften the adhering lymph; the scarification or abrasion of the skin is then made with the lancet or needle, and the virus rubbed well into the scarified spot, or, in using the giycerinized virus, the latter is simply rubbed into the scarified area. In using animal virus the successive stages of development are usually one or two days later than when humanized virus is used. In the former case the areola is rarely developed before the ninth day. Certain complications are likely to occur in the course of the vaccinia, of which the student should be aware. When the areola appears there is usually more or less fever. Sometimes the constitutional manifestations are decidedly marked, fever of a high grade being not uncommon. In addition to the glandular enlargement and tenderness, an outbreak of roseola some- times comes on about the ninth or tenth day. This eruption may be mistaken for scarlet fever, but if it is remembered that two infectious diseases rarely co-exist in one individual during their full develop- ment this error will be avoided. Erysipelas involving the entire arm is sometimes observed as a complication of vaccination. This, in nearly every case, depends upon some depravement of the patient's constitution, malnutrition, bad sanitary surroundings, or, perhaps, more frequently, chronic alco- holism. Individuals who are habitually intemperate in the indulgence of alcoholic liquors are especially unfavorable subjects for vaccination. The results are, fortunately, rarely serious to the patient. Another inconvenient complication of vaccination is the forma- tion of a deep, ill-looking, sloughing ulcer at the vaccinated point. This is the result of infection with impure virus or lack of cleanliness in making the scarification. It should be borne in mind that a very sore arm, especially if followed by the formation of an ulcer or gan- grenous sore, may not be protective against small-pox. Such a patient should not be considered properly vaccinated, and must be revaccin- ated as soon as he recovers, or immediately if there is any danger of small-pox infection. Children with eczematous eruptions, however, localized upon any portion of the body, should not be vaccinated until the eruption is first cured, except in times of danger from small-pox. The eczema will be almost certainly rendered worse in consequence of the general hyperemia accompanying the febrile reaction, and the physician who performs the vaccination will be blamed for causing the skin disease. 408 TEXT-BOOK OF HYGIENE. The author has placed on record^'' two cases of general psoriasis following vaccination, and other cases have been since reported. Urticaria and exudative erythema have also been repeatedly observed. As before stated, syphilis may be communicated to the vaccines by vaccine virus obtained from a syphilitic subject, but this acci- dent is infrequent. There can be little doubt that some of the cases reported as "vaccinal syphilis" are cases of tardy hereditary syphilis, lighted up by the general systemic disturbance following vaccination. In some cases tetanus has followed vaccination. This unfortunate complication may be due either to the tetanus bacilli gaining access to the virus in the process of preparation, or infection of the patient during vaccination. Next in importance to vaccination in the prophylaxis of small- pox is prompt isolation of the sick. No one but the medical and other attendants of the sick should be allowed to come in contact with them. All attendants and other persons exposed to the infection should, of course, be promptly vaccinated, unless this has been successfully done within the previous year or two. Disinfection of all discharges from the patient and of the room and its contents, after the patient has recovered or died, must be practiced. The best disinfectants in small-pox are bichloride of mercury, free chlorine, sulphurous acid, and formaldehyde. When it is learned that a person has small-pox, if he is not re- moved to a special hospital, a room should be prepared for his occu- pancy. The carpets should be taken up and the floor kept clean. Window-curtains and unnecessary furniture and drapery should be re- moved from, the room. After recovery of the patient the bed-clothing must be thoroughly disinfected with steam or sulphurous acid, or de- stroyed by fire. The individual himself should not be allowed to mingle with healthy persons until all danger of infection is passed and the surface of his body has been thoroughly disinfected. At a conference of sanitary officials in the city of Chicago (May, 1894) the following propositions were adopted. They represent the most advanced conclusions of competent authority upon the most practical means of limiting the spread of sroall-pox : — "1. The city should be divided into districts containing not more than 10,000 people. "2. Each district should be placed under the supervision of a competent medical inspector with necessary assistants to (a) make a house-to-house inspection; (h) to successfully vaccinate, within "Journal Cutaneous and Venous Diseases, vol. i, No. 1, p. 11. ASIATIC CHOLERA. 409 the shortest possible time, all persons who have not been vaccinated during the outbreak, and that the first vaccination be within seven days; (c) to properly disinfect all houses and their contents where small-pox occurs. "3. Necessary means and appliances for efficient disinfection of materials, premises, etc., should be provided as the exigencies of each district may require. "4. Each case of small-pox should be immediately removed to a suitably constructed and properly equipped and officered isolation hospital. "5. Except in extreme cold weather, hospital tents, as prescribed in the United States Army Regulations, floored and warmed, are pre- ferable to the average hospital or private dwelling, and increase the chances of recovery of the patients. Cases of small-pox necessarily^ detained in their own homes should, with their attendants, be rigidly isolated during the period of danger, and physicians visiting such patients professionally shall be subject to such regulations as may be prescribed by the local health officer. "6. Persons exposed to small-pox contagion should be immedi- ately vaccinated or revaccinated, and kept imder observation for not less than fourteen days from time of last exposure. "7. It is the sense of this conference that where such measures are all enforced it will net be necessary for neighboring cities and states to exclude all persons who come from such city who are not protected against small-pox by vaccination, and to require disinfec- tion of all baggage and merchandise capable of conveying small-pox infection.^' ASIATIC CHOLERA. A disease which causes the death of three-fourths of a million of human beings where it is endemic within the space of flve years, and which makes periodical excursions, spreading over nearly the entire inhabited globe with destructive violence, must surely command the interested attention of every intelligent person. Asiatic cholera is endemic in India, where it probably originated centuries ago. Some authors claim to have found satisfactory evidence of its existence in the writings of the classical authors of India and Greece at a period as early as the second century of the Christian era. The evidence is, however, not beyond question. In the sixteenth and seventeenth cen- turies European travelers in the East gave pretty exact accounts of the disease. One of the most definite of these was given by Gaspar Correa, an officer in Vasco de Gamma's expedition to Calicut. He 410 TEXT-BOOK OF HYGIENE. states that Zamorin, the chief of Calicut, lost 20,000 of his troops by the disease. A still more definite and the first trustworthy account is that of Sonnerat, a French traveler. He describes a pestilence hav- ing all the characters now recognized as belonging to Asiatic cholera,- which prevailed in the neighborhood of Pondicherry and the Coro- mandel coast in 1768 and 1769, and which carried off 60,000 of those attacked by it within a year. Dr. McPherson, in his "History of Cholera,^' gives numerous references which indisuptably establish the endemic existence of the disease in India prior to the present cen- tury. Being endemically prevalent over a greater or less area of India for many years, cholera finally, in 1817, crossed the boundaries of that country, and, advancing in a southeasterly direction, invaded Ceylon and the Sunda Islands in 1818. In a westerly direction the disease was carried to the islands of Mauritius and Eeunion, and reached the African coast in 1820. During this year it also traveled northeasterly, devasting the Chinese Empire for the two following years, reach- ing Nagasaki, in Japan, in 1822. In 1821 the disease spread from India in a westerly direction, extending along the east coast of Arabia to the border of Mesopotamia and Persia. In the spring of 1822 it began with renewed violence, following the river Tigris to Kurdistan, and, extending farther in a westerly direction, reached the Mediterranean coast of Syria. In the following year, 1823, it extended from Persia into Asiatic Eussia, reaching Astrachan on the European border in September, but dying out nearly everywhere beyond the borders of India during the ensuing winter. In 1826 cholera again advanced from India, reaching Orenburg in Eussia, in 1829, and in the following winter appeared in St. Peters- burg. Extending to the north and south, it invaded Finland and Poland the same year. From Persia the disease spread to Egypt and Palestine in 1830-31. From Eussia the pestilence invaded Germany in 1831, passing thence in 1832 into France, the British Isles, Belgium, the ISTether- lands, Norway, and Sweden. In the latter year cholera crossed the Atlantic Ocean for the first time, being carried to Canada by emi- grants from Ireland, and spreading thence to the United States by way of Detroit. In the same j^ear it was imported into New York by emigrants, and rapidly spread along the Atlantic coast. During the winter of 1832 it appeared at Few Orleans, and passed thence up the Mississippi Valley. Extending into the Indian country, causing sad ASIATIC CHOLERA. 411 havoc among the aborigines, it advanced westward until its further progress was stayed by the shores of the Pacific Ocean. In 1834 it reappeared on the east coast of the United States, but did not gain much headway, and in the following year New Orleans was again in- vaded by way of Cuba. It was imported into Mexico in 1833. In 1835 it appeared for the first time in South America, being restricted, however, to a mild epidemic on the Guiana coast. While the pestilence was advancing in the Western Hemisphere, it also spread throughout Southern Europe, invading, in turn, Portu- gal, Spain, and Italy. Extending in an easterly direction from India, the disease reached China and Japan in 1830-31; westwardly, Africa was invaded in 1834, and ravaged by the epidemic during the following three years. This second extensive outbreak of cholera ended in 1837, disap- pearing at all points beyond the borders of India. In 1846 the dis- ease again advanced beyond its natural confines, reaching Europe, by way of Turkey, in 1848. In the autumn of this year it also ap- peared in Great Britain, Belgium, the Netherlands, Sweden, and the United States, entering by way of New York and New Orleans. In the succeeding two years the entire extent of country east of the Eocky Mountains was invaded. During 1851 and 1852 the disease was fre- quently imported by emigrants, who were annually arriving in great numbers from the various infected countries of Europe. In 1853 and 1854, cholera again prevailed extensively in this country, being, how- ever, traceable to renewed importation of infected material from abroad. In the following two years it also broke out in numerous South American States, where it prevailed at intervals until 1863. Hardly had this third great pandemic come to an end before the disease again advanced from the Ganges, spreading throughout India, and extending to China, Japan, and the East India Archipelago during the years 1863 to 1865. In the latter year it reached Europe by way of Malta and Marseilles. It rapidly spread over the Continent, and in 1866 was imported into this country by way of Halifax, New York, and New Orleans. This epidemic prevailed extensively in the West- ern States, but produced only slight ravages on the Atlantic coast, being kept in check by appropriate sanitary measures. In the same year (1866) the disease was also carried to South America, and in- vaded, for the first time, the States bordering on the Rio de la Plata and the Pacific coast of the Continent. WHiile the epidemic was thus advancing westward from its home in India, it was at the same time spreading northwardly over the en- 412 TEXT-BOOK OF HYGIENE, tire western part of Asia, and in a southeasterly direction over North- ern Africa. In the latter continent it prevailed from 1865 to 1869. Cholera never entirely disappeared in Eussia during the latter half of the sixth decade, and in 1870 it again broke out with vio- lence, carrying off a quarter of a million of the inhabitants before dying out in 1873. It spread from Eussia into Germany and France, and was imported, in 1873, into this country, entering by way of New Orleans and extending up the Mississippi Valley. None of the Atlantic-coast cities suffered from the epidemic in 1873, and since that year the United States have been entirely free from the disease, with the exception of a few imported cases in New York Harbor in 1887. In June, 1883, a new epidemic of cholera broke out in Egypt, where it raged with great violence. The disease first appeared in Damietta, near the outlet of the Suez Canal. It was unquestionably imported from India, probably Bombay, where it j^revailed as early as the month of May. At the time of the outbreak in Damietta that city was overcrowded with people who had come to attend a great re- ligious fair and festival. It has been proven that pilgrims from Bom- bay were among the attendants at this fair. The epidemic came to an end in Egypt in the autumn of 1883. In the same year (1883) a small outbreak occurred in Marseilles, but intelligence of it was care- fully suppressed by the authorities. The disease does not seem to have spread from this centre, but in June of the following year cholera broke out in Toulon, having probably been imported in a transport ship returning from Tonquin. This outbreak was very violent and rapidly spread throughout Southern France, Italy, and Spain. After apparently dying out during the winter, it reappeared in the spring of 1885 with renewed violence. The total number of cases in Spain alone in the latter year was over one-third of a million, with nearly 120,000 deaths. In the summer of 1885 cholera also broke out in a virulent form in Japan, and, after a cessation during the following winter, recurred with increased fatality in 1886. In the latter year there were over 100,000 deaths from the disease in that country. During 1886 and 1887 cholera continued in Southeastern Italy and in the Austrian dominions at the head of the Adriatic. A few cases occurred in France and Germany, but by stringent sanitary meas- ures an epidemic was averted. In November, 1886, cholera was carried to South America in an Italian sliip, the ^'Perseo," bound from Genoa to Buenos Ayres. The disease rapidly spread in the Argentine Eepublic, and, crossing the. ASIATIC CHOLERA. 413 Andean range, invaded the Pacific coast of the South American con- tinent for the second time, reaching Chili and Bolivia and threatening Peru and Brazil. In Chili alone there were over 10,000 deaths in the first six months of 1887. The further progress of the epidemic was arrested and the entire Western Hemisphere is now free from the disease. Prom July to December, 1889, cholera prevailed with consider- able virulence in Mesopotamia. In 1890 it reappeared in Spain; in 1893 in France and Germany, raging with great violence in Ham- burg. Nearly 8000 persons died from the disease in the latter city. Some cases were brought thence to New York, but the active sanitary measures taken were successful in preventing its further spread. This brief historical sketch of all the epidemics of cholera ob- served beyond the borders of India demonstrates several facts : first, that the home or breeding-place of cholera is in India, especially the delta of the Ganges, whence it spreads at intervals throughout the world; second, that it always advances along the lines of travel of large bodies of human beings ; and third, that it advances, by pre- ference, along water-routes. Exceptions undoubtedly occur, but the rule is. a general one. The disease seems to spread with difficulty along the lines of railroad. When the disease has extended from New Orleans it has always been up the Mississippi Valley, expending its violence upon the river cities— Vicksburg, Memphis, St. Louis, and Cincinnati. Several factors must concur before there can be an epidemic of cholera. These are : first, the cholera poison ; second, certain local conditions of air, soil, or water; and, third, individual predisposition. Without a concurrence of all these conditions no outbreak can occur. If, by any means, the co-existence of these three conditions can be prevented, cholera can be averted. The following are facts bearing upon this question: Cholera is communicated through the agency of a specific poison. This does not admit of doubt. The researches of Dr. Eobert Koch, of Germany, have established the fact that a micro-organism found in the intestinal discharges of cholera pa- tients and in the bodies of those dead with the disease is the active agent in propagating the malady. This organism, named by Koch the "comma bacillus," from its general resemblance to a comma, was first discovered by this eminent pathologist in the intestinal contents of cholera corpses in Egypt, in 1883, and in the following year more thoroughly studied in Calcutta, whither he had been sent by the Gorman government to pursue his investigations. It has been dem- 414 TEXT-BOOK OF HYGIENE. onstrated that this germ is always present in the discharges of cholera patients, and up to this time it has not been found in any other dis- ease. Experiments upon animals have also shown that cholera can be produced in the latter by introducing the germ into their bodies in various ways. The demonstration of the bacterial nature of cholera seems to be complete. While cholera cannot be regarded as personally contagious in the same sense or in the same degree as small-pox, there can be no doubt that it is spread only by the poison from other cases of the disease. Generally this disease is conveyed by water polluted by the dejections of cholera patients. The regularity of its march along routes by which the intercourse of human beings takes place, and always in connection with other cases of cholera, proves this. There is no un- doubted case on record where genuine cholera has been spontane- ously developed outside of India. That certain geological and perhaps meteorological conditions are necessary for the propagation or virulence of the poison of cholera is beyond dispute. Outbreaks usually take place during the summer or autumn, and nearly always partly or entirely die out dur- ing cold weather. Further, in nearly all epidemics, certain cities or towns, or portions of a town, into which persons sick with cholera are brought, and where the poison of the disease is thus imported, remain exempt from the effects of the epidemic. The inference to be drawn from this fact is that in such localities the local conditions are un- favorable to the development of the poisonous germ, and it becomes inert. In India all the local conditions favorable to the propagation of the cholera-germ are found. The filthy personal habits of the people, the overcrowding, the intense heat, the lack of sufficient, appropriate, or properly-prepared food, and the extensive pollution of the water- supply, all combine to produce the necessary conditions of develop- ment of the cause of cholera. These conditions, doubtless, to a con- siderable extent, give rise to that depression of the system which seems necessary to constitute the individual predisposition to become infected. Given, then, at any place, a number of persons of a lowered de- gree of vitality — that is to say, persons not capable of resisting unfa- vorable influences upon their health under unfavoring conditions; given conditions of climate, water, and soil more or less similar to those existing in India: only the introduction of the third factor, the cholera poison, is needed to cause an outbreak. In many cities ASIATIC CHOLERA. 415 of this country and Europe, as proven by the epidemics in Toulon, Marseilles, Naples, and other cities of Italy and Spain, the condi- tions are present which would furnish the most favorable breeding- place for the cholera-germ if introduced. The dejections and vomited matters of cholera patients contain the active agent which produces the disease. The contagious prin- ciple contained in these excretions, the cholera-germ or "comma bacillus" discovered by Koch, may gain an entrance into the body through the drinking-water or through infected air. Probably both modes are equally competent channels of infection. The prevailing theory is that pollution of the drinking-water is the most frequent source of the rapid spread of the disease. A very striking instance of this occurred in London during the epidemic of 1854, which has already been referred to,^'^ and during the cholera epidemic in Ham- burg in 1893. Another striking instance of the communication of cholera by polluted water has been reported by Mr. John Simon, long the chief medical officer of the English "Local Government Board." The facts are as follow: The Lambeth Water Company drew its supply from the Thames, at Ditton, above the influence of the London sew- age and the tidal flux. The Southwark and Vauxhall Company drew its supply from the river near Vauxhall and Chelsea. The water of the Lambeth Company was tolerably pure, and that of the South- wark and Vauxhall Company was very impure. The water of both companies was distributed in the same district at the same time and among the same class of people, the pipes of the two companies being laid pretty evenly in the same areas, in many places running side by side in the same streets, and the houses supplied being pretty equally distributed. The deaths from cholera in the houses supplied by the Lambeth Company were at the rate of 37, and in the houses supplied by the Southwark and Vauxhall Company at the rate of 130, to every 10,000 persons living. It appears, therefore, that of the drinkers of the foul water about three and a half times as many as those who drank the pure water died of cholera. Iti addition to the influence of polluted drinking-water in spread- ing cholera, must be mentioned articles of food contaminated with the infectious matter of the disease. It is also no longer open to question that persons may become infected by handling the clothing and bedding of cholera patients. Laundresses are in special danger from this source. "See ante, page 64. 41g TEXT-BOOK OF HYGIENE. The prophylaxis against cholera comprises such measures as will prevent the admission of the cholera-poison into a community, arrest the development of the poison after its introduction, and reduce the individual susceptibility to attack. It is evident from the foregoing that if the introduction of the cholera-poison could be prevented no outbreak of the disease could occur. With this in view, some have urged the enforcement of a strict policy of non-intercourse with the infected localities. But at the present day few sanitarians advocate these extreme measures. A modified system of restricted intercourse is supported by many au- thorities, who claim that by the adoption of a thorough system of maritime inspection, disinfection, and observation — a rational quar- antine, in fact — the poison can be rendered ineffective or its entrance into a community prevented. The best authorities, however, think that it is not only easier, but far more effective to place the threatened locality in such a sanitary condition that the development of the cholera-poison cannot take place. The contrast between the effectiveness of quarantine and local sanitation as safeguards against cholera has been well expressed by von Pettenkofer, who compares cholera epidemics to powder explo- sions. The virus of cholera, he says, is the spark that evades the strictest, quarantine ; the powder is the ensemble of local conditions which predispose to the outbreak. "It is wiser, therefore, to seek out and remove the powder than to run after and try to extinguish each individual spark before it drops upon a mass of powder, and, igniting it, causes an explosion which blows us into the air with our extinguishers in our hands." The measures of sanitation to be enforced are such as will se- cure cleanliness of person, of habitation and surroundings, of air, of water, and of soil. Pollution of the soil should be especially guarded against, for a polluted soil means impure air and water, and these mean, if not an infectious disease, at least a heightened recep- tivity to its influence. The quality of the drinking-water used must be above suspicion of contamination by the poison. Unless the latter can be positively excluded, all drinking-water ' should first be boiled. It may then be cooled by pure ice. The individual predisposition to cholera is best guarded against by keeping the body clean and well nourished, and the mind free from worry. Underfeeding, anxiety, overwork, exposure to extremes of temperature, intemperance in eating and drinking should all be ASIATIC CHOLERA. 417 avoided, as they tend to reduce the resistance of the system to the influence of the morbid poison. Certain measures of personal prophylaxis which have proven useful heretofore should be adopted wherever cholera prevails. One of the best of these is the use of sulphuric-acid lemonade as a drink. Ten to 15 drops of dilute sulphuric acid in a glass of water, sweet- ened with sugar, may be drunk instead of water. Experience with it during the epidemic of 1866 has demonstrated its great value as a preventive of cholera. The later researches of Koch have also shown that the "comma bacillus," or spirillum, cannot live in acid solutions. Hence, it is probable that if the contents of the stomach were always kept acid no infection could occur through absorption from the stomach. A painless diarrhea, called cholerine, attacks many persons dur- ing cholera epidemics. This disorder is easily curable if promptly attended to, but if allowed to run on it may develop into a malig- nant attack of cholera. Among the means of securing prompt treatment of the poorer classes in times of epidemics is the establishment of numerous public dispensaries, where medical aid can always be obtained. The estab- lishment of such dispensaries and, if possible, of temporary hospitals in the crowded portions of cities is a very important part of the prophylactic treatment. Inasmuch as it seems definitely established that the discharges from the stomach and intestines are the active agents in propagating the disease, the immediate disinfection of such discharges is vitally important. The stools and vomited matters must be rendered in- nocuous by germicidal agents, such as mercuric; chloride, carbolic acid, or chloride of lime. Clothing and bedding should be disinfected with superheated steam, thorough boiling, or fumigation with sulphur dioxide or chlorine. Infected articles of this kind should not be sent to a laundry until they have been thoroughly disinfected by one of the above-mentioned means. Apartments which have been occupied by cholera patients should be thoroughly disinfected before being re-occupied, and afterward freely exposed to the air by opening doors and windows. The walls may also be washed with a solution of mercuric chloride. The most efficient disinfectant is mercuric chloride in the pro- portion of 1 part in 2000 of the material to be disinfected. The readiest way of securing disinfection with this agent is to add a 21 418 TEXT-BOOK OF HYGIENE. solution of 1 to 1000 to an equal i^roportion of the discharges to be rendered innocuous. The mercuric chloride acts slowly, and hence the infected material should be exposed to the action of the disin- fecting agent for at least two hours before it can safely be thrown into sewers or cess-pools. There are several serious objections to the indiscriminate use of mercuric chloride by the public as a disinfectant. In the first place, it is intensely poisonous, and its perfectly transparent and inodorous solution might be readily accidentally drunk and cause fatal results. To reduce this danger, the Committee on Disinfectants of the Amer- ican Public Health Association recommended the addition of perman- ganate of potash or of sulphate of copper (blue vitriol) to cobr the solution. Another serious objection to mercuric chloride is that it cannot be used where the disinfected material must pass through lead pipe, as this is rapidly corroded by the sublimate. In many water- closets it cannot therefore be used. Chloride of lime (bleaching powder) has been found to be a very rapid and efficient disinfectant, as well as a deodorizer; but the chlorine, upon which its effectiveness depends, is often so deficient in proportion, and the compound so readily deteriorates that, unless a preparation can be obtained that contains at least 25 per cent, of available chlorine, it may prove injurious by causing a false sense of security. A trustworthy preparation may be dissolved in water, when required, in the proportion of 1 to 100. An objection to its use is the pungent odor of chlorine, which is very offensive to many persons. Dr. Koch recommends carbolic acid, which he has sho^vn will kill the "comma bacilli" in a dilution of 1 to 20 of water. The or- dinary preparations of carbolic acid sold as disinfectants are, how- ever, not to be relied on, many of them not containing more than 2 per cent, of the acid. Further dilution of these agents would alto- gether destroy their disinfecting power. The purer article is, on the other hand, too expensive to be used as a disinfectant. Little's soluble phenyle is an efficient disinfectant in the pro- portion of 2 per cent. (1 to 50). It is furnished of uniform strength, is moderately cheap, non-poisonous, and readily miscible with water. In addition to its disinfecting power, it is also an excellent deodor- izer, promptly removing all odors of decomposition and putrefaction. Its only objection is a rather pungent although not unpleasant odor, which somewhat resembles creasote. In the very beginning of an epidemic, prompt isolation of the sick and thorough disinfection of the surroundings of the patient RELAPSING FEVER. 419 may check the spread of the disease. Much cannot be expected from these measures, however, unless the local sanitary conditions are such as offer a hindrance to the development of the cholera-poison. It is plain, therefore, that prophylactic measures against cholera, to be effective, must be brought into requisition before the epidemic has begun. After the outbreak of the disease it may be too late to put the threatened locality in a good sanitary condition. It is of the highest importance that preventive measures be enforced early. Above all, the purity of the drinking-water must be safeguarded. RELAPSING FEVER. Eelapsing fever was first clearly described by Dr. John Eutty, in his "Chronological History of the Weather, Seasons, and Diseases of Dublin from 1725 to 1765."^^ During the last century relapsing Fig. 44. — Spiroehseta Obermeieri. X 380. fever was frequently met with in epidemic form in Ireland and Scot- land. In 1847 the disease invaded a number of the larger cities of England. From 1868 to 1873 it prevailed extensively in England and Scotland. On the continent of Europe it was first observed in Kussia in 1833. In Germany it was not recognized as a distinct disease until 1847, but did not prevail epidemically until 1868. Since then it has often been observed in that country. '"London, 1770. 420 TEXT-BOOK OF HYGIENE. Eelapsing fever is very prevalent in India, where it was first observed in 1856 by Sutherland. In China and in the countries of Africa bordering on the Eed Sea the disease has been recognized by observers. In the United States it was first observed among emigrants in Philadelphia in 1844, and again in 1869. It was conveyed to other places, but has never prevailed extensively in this country. It has not been observed in the United States since 1871. The predisposing causes of relapsing fever are, above all, bad sanitary surroundings. Want and overcrowding seem to be much less important factors than in typhus fever. Although relapsing fever has, since it was first clear^.y distin- guished from typhus and other continued fevers, been recognized as an eminently contagious and infectious disease, it was not until 1873 that its immediate cause became known. In that year Obermeier dis- covered in the blood of patients ill with this disease a minute, spiral, mobile organism, now known as the spirillum or Spirochcete Oher- meieri. (Fig. 44.) Obermeier and other observers, prominent among Mdiom is Dr. Henry V. Carter, have demonstrated the constant presence of these organisms in the blood during the attack. Carter and Koch have induced the disease in monkeys by inoculation of the parasite, and Moschutkowski has successfully inoculated it in the human subject. No doubt can exist at the present day that the spirillum of Obermeier is the true cause of relapsing fever. The preventive measures consist in attention to details of per- sonal hygiene; in other words, local sanitation, disinfection of in- fected materials (fomites), and complete isolation of the sick. TYPHOID FEVER. The first accurate clinical accounts of typhoid fever date from the seventeenth century, when Baglivi, Willis, Sydenham, and others described cases of fever which in their clinical characters corres- pond to the disease now kno's\Ti as typhoid fever. Strother, however, in 1729, first gave a description of the anatomical characters of the disease, which he says is a "symptomatical fever, arising from an inflammation, or an ulcer, fixed on some of the bowels." Bretonneau and Louis, in France; Hildenbrand, in Germany; William Jenner, in England; and Drs. Gerhard and Pennock, in this country, clearly pointed out the essential distinction between typhoid and other fevers. At the present day typhoid fever is met with everywhere through- TYPHOID FEVER. 421 out the world. It is at nearly all times a constituent of mortality tables. It affects by preference persons between the ages of 15 and 30 years, although no age is entirely exempt. It is always more prevalent in the autumn and winter. The disease is due to a micro-organism which gains entrance into the body through the digestive tract. The micro-organism was first observed by Eberth and Gaffky, and is termed bacillus typhosus. It is found in the intestinal canal, and especially in the characteristic intestinal lesions of this fever. It is contained in the dejections of patients. The disease is not immediately contagious, like typhus fever. Fig. 45. — Pure Culture of Typhoid Bacilli, showing Clumping when Brought in Contact with Blood from Typhoid Patients. (Widal reaction.) The medium through which the poison is introduced into the body may be drinking-water, food, milk, or other articles containing the infective agent. Localized epidemics due to infected water, milk, and oysters have been frequently reported.^** At present the evidence is in favor of the view that cases "of typhoid fever are always derived from pre-existing cases. The germ may exist in sewage and be carried from place to place; it may be carried into the soil from cess-pools receiving typhoid dejections, and thus gain access into wells and pollute the drinking-water. By. the admixture of such water with milk or other food the disease may be propagated. The germs are frequently carried by flies. The prophylactic measures against typhoid fever comprise iso- '' See ante, pp. Gl-04. 422 TEXT-BOOK OF HYGIENE. lation of the sick, prompt disinfection of the discharges, and cleanli- ness in the widest sense. The water- and food- supplies must be carefully guarded against contamination with the bacillus, excreta must be removed from the immediate vicinity of dwellings. The requisites for prevention may be summed up as pure air, pure v/ater, uncontaminated food, and a clean soil. TYPHUS FEVER. Wide-spread pestilences are nearly always accompaniments of famine and war. Of all pestilential diseases, none is so regular in its coincidence with these conditions as typhus fever. The earliest accounts which unquestionably refer to this disease date from the eleventh century, when it was observed at a number of places in Italy. In the succeeding centuries isolated accounts of it appeared in the chronicles of the times, but no scientific description of it appeared until the sixteenth century. During the seventeenth, eighteenth, and the early part of the nineteenth centuries it prevailed extensively throughout Europe. The constant wars and consequent disturbances of the social relations of the people, famines, overcrowding, filth, excesses of all kinds, contributed largely to the development and spread of typhus fever. For a number of years past no extensive epidemic of the disease has been observed, although in this country and in Europe localized outbreaks are frequently met with. Typhus fever is somewhat more prevalent in the winter and early spring months than during the rest of the year, but not very markedly so. At present, typhus fever is nearly always limited to times and places where the conditions favoring its development exist. Wherever overcrowding, in connection with filth, insufficient food, and bad habits are present, tjq^hus fever is likely to be a visitor. Thus, in overcrowded and ill- ventilated emigrant ships, in Jails and work- houses, and in camps, especially when stress of weather compels the crowding together of soldiers in close huts or barracks, the disease frequently breaks out. When typhus appears in a community, those classes of the people who are subjected to the conditions just mentioned are almost exclusively attacked. In cities, the dwellers in crowded tenements, or in courts and alleys, suffer most severely — are, in fact, almost the only ones attacked. An exception must, however, be made in the case of hospital physicians and attendants where typhus-fever patients are treated. The mortality among these is alwaj^s large. YELLOW FEVER. 423 Typhus fever is contagious and infectious. The cause is un- known. An exposure for a length of time to an atmosphere impreg- nated with the poison may suffice to induce an attack. The poison may also be conveyed from place to place in fomites. Physicians may carry it in their clothing, if they have been exposed to typhus atmos- phere. The prevention of typhus fever consists in the institution of such measures as will secure pure air, pure water, a clean soil and dwell- ings, and cleanliness of body and clothing. When an outbreak occurs, the sick should be promptly isolated, the well persons removed from the building in v/hich the cases have occurred, and efficient measures of disinfection carried out. The sick should be treated in the open air as much as possible. YELLOW FEVER. The West India Islands, the Gulf coast of Mexico, the northern part of the Atlantic coast of South America, and a limited section of the west coast of Africa constitute the, present home of yellow fever. From this area (the so-called "yellow-fever zone") the disease is fre- quently transported to contiguous or distant countries. The South Atlantic and Gulf coasts of the United States and the shores of the Caribbean Sea are the most liable to the epidemic visitation of this pestilence. The first trustworthy account of an epidemic of yellow fever dates from the year 1635, when it prevailed on the Island of Guade- loupe. This and the adjoining islands of Dominica, Martinique, and Barbadoes were invaded a number of times in the fifty years follow- ing the above date. Jamaica was invaded in 1655 and Domingo the year after. In 1693 the first appearance of the disease is mentioned in the United States, being observed in Boston, Philadelphia, and Charleston. In 1699 it appeared as an epidemic in Vera Cruz, and re-appeared in Philadelphia and Charleston. Since the year 1700, the disease has appeared in an epidemic form, at one or more places within the present limits of the United States, eighty times, the last con- siderable invasion being at Jacksonville and other places in Florida, and Decatur, in Alabama, in 1888, and to a lesser extent in New Orleans in 1903. It has also been endemic in Cuba until recent years. In South America yellow fever appeared for the first time in 1740. In 1849 the disease was imported into Brazil, and has since 424 TEXT-BOOK OF HYGIENE. then been endemic. Peru and the Argentine Eepublic have also suf- fered several severe visitations of 3"ellow fever since 185-i. On the west coast of Africa, 5^ellow fever seems to be endemic in the peninsula of Sierra Leone, where it has been frequently ob- served since 1816. It has also prevailed epidemically in Senegambia and a number of the islands off the northern portion of the west African coast. In Europe, Spain and Portugal have been the only countries to suffer from yellow-fever epidemics. Although the causes of yellow fever cannot be definitely stated, it is well known that it only occurs endemically within the tropics, and prevails epidemically elsewhere only during the summer. Of 180 epi- demics observed in the United States and Bermudas, 154 began in July, August, and September. Of the remaining 26, none began in the six months from November to April. A temperature of 26° C. and a high humidity are generally con- sidered essential to produce an outbreak of the disease. Of other necessary meteorological conditions nothing is known. That the specific cause of yellow fever is a micro-organism ap- pears probable from a consideration of the clinical history of the disease and its mode of propagation. Up to the present time, how- ever, none of the various organisms described as causative have made good the claims advanced by their discoverers. Surgeon-General Sternberg has shown that neither the organism of Freire, of Car- mona, of Babes, of F. S. Billings, of Finlay, or of Gibier is the true cause of yellow fever. It seems to be Avell established that the most filthy and insani- tary portions of cities are those principally ravaged by yellow fever. It has also been firmly established that the disease is propagated through the agency of a certain species of mosquito {stegomyia fasci- ata), the latter acting as an intermediate host. Yellow fever is not endemic within the limits of the United States, and has probably never originated here. The instances in which it has appeared to do so may be explained by the persistence of the morbific agent through one or more winters, or by a new importa- tion which has escaped observation. Yellow fever frequently breaks out on shipboard and causes much loss of life. There is no evidence that it originates on ships; it is only acquired after intercourse with an infected ship or infected place. The question of personal contagion of yellow fever has been decided negatively. The disease is infectious, but persons sick with SCARLET FEVER AND MEASLES. 425 the disease do not communicate it, the disease being communicated from the sick to the well by the bites of infected mosquitoes. The preventive measures indicated against yellow fever appear from the foregoing : they are strict sanitary inspection to prevent the introduction of a person sick with the disease; to prevent the mos- quitoes from coming in contact with yellow fever patients; and to employ such measures as would lead to the extermination of mosquitoes. When the disease becomes epidemic in a city, the inhabitants should be removed to temporary camps beyond the infected area. The experience of the city of Memphis in 1879, and that of various locali- ties in Florida in 1888, New Orleans, and especially Cuba, encour- ages the hope that by prompt isolation of the sick and strict enforce- ment of sanitary measures with especial reference to mosquitoes, the terrors of yellow fever can be largely averted. The sick should be promptly isolated, and protected by screening. SCARLET FEVER AND MEASLES. The early history of these two contagious eruptive fevers is in- extricably blended together. Up to the latter half of the seventeenth century the distinction between the two was not made by writers. Sydenham was among the first who clearly separated scarlet fever from measles and gave it a distinct name. Since the Great English Hippocrates, the essential character of scarlet fever has been recog- nized by all physicians, and now it is never, or but rarely, confounded with measles. Of the two diseases, measles is somewhat more generally preva- lent, although both occur usually in epidemics. There is hardly a country in which measles has not been observed, while the continents of Asia and Africa have remained measurably exempt from scarlet fever up to the present time, although epidemics have been recorded in India and Japan. Hirsch states that scarlet fever was first observed in this country in 1735, at Kingston, Mass., quoting as authorities Dr. Douglass, of Boston, and Dr. Golden, of New York. The latter, however, in a letter to Dr. Fothergill,^" clearly describes diphtheria, and not scar- let fever. Its distribution is now general, but it is said to be much milder in the southern than in other portions of the United States. The prevalence of measles is not limited to any geographical section. ^Medical Observations and Inquiries, vol. i, p. 22L London, 1776. 426 TEXT-BOOK OF HYGIENE. Epidemics of measles usually begin during cold weather. Of 530 epidemics observed in Europe and North America, 339 occurred during the colder and 191 during the warmer months. In 313 of these, the height of the epidemic occurred 135 times in winter and spring, and only 78 times during summer and autumn. Scarlet fever epidemics occur more frequently in autumn than at any other season. The cause of scarlet fever or of measles is not to be sought in climatic influences, insanitary surroundings, or special natural con- ditions of air, water, or soil. Both diseases are contagious and infec- tious, and the contagion is transmitted either by fomites (clothing, letters, etc.), infected air, drinking-water, or milk. Several observers have claimed the discovery of the specific or- ganism of scarlet fever, but no trustworthy evidence has yet been fur- nished that the problem is solved. On a previous page reference has been made to the probable connection between a disease of milk-cattle and scarlet fever. The measures for the prevention of both diseases are isolation and thorough disinfection. DIPHTHERIA. Under the names of Syriac and Egyptian ulcers, Aretseus, a writer of the second century, described various forms of malignant sore throat. The disease now called diphtheria prevailed at various places in Europe during the Middle Ages. In this country it was first observed about the middle of the last century, and in 1771 Dr. Samuel Bard, of New York, described it very accurately. Although repeated severe outbreaks occurred in Europe in the early part of the present century, it was not until 1857 that it again attracted attention by its epidemic prevalence in the United States. Since that time it has spread throughout the country, and is at present one of the most generally diffused, as well as one of the most fatal, of the contagious diseases. In certain epidemics its malignancy is very marked, while in others it seems to be a rather mild affection. Diphtheria is personally contagious. The infecting agent is a micro-organism first described by Loffler. The bacillus can be dem- onstrated in the secretions from the throat or nose of diphtheria patients. The diphtheria bacillus may also be present in the throats of healthy individuals who are at the time insusceptible to the dis- ease, but are nevertheless carriers of the infection. The question as to the identity of diphtheria and croup is not DIPHTHERIA. 427 merely a clinical one^ but has an important bearing upon preventive medicine. If croup is a non-contagious and non-infectious disease no precautions will be necessary to prevent its spread to healthy persons. If, on the other hand, diphtheria and croup are identical in nature, the danger of infection is equally great in both diseases. With the evidence furnished by the bacteriologist before us, we can have no further doubt as to the identity of the two diseases. Diphtheria Is inoculable upon animals, and may through this medium be transmitted to man. Persons sick with diphtheria should be carefully isolated; no one but the immediate attendants should be allowed to come in con- tact with the patients. Table utensils, bedding, and clothing used by the sick should be thoroughly disinfected by steam or boiling water before being used by others. Intimate contact with the sick, such as Fig. 46.— Diphtheria Bacilli. (Park.) kissing, should be strictly prohibited. There seems no room for doubt that the diphtheria bacillus can also be carried in the clothing. Hence, physicians and nurses should be especially careful in person- ally disinfecting themselves after contact with a case of diphtheria. After death or recovery of the patient, the apartment occupied during the illness should be disinfected. Children recovering from diphtheria, scarlet fever, measles, or small-pox, should not be permitted to attend school for at least four weeks after recovery. It is believed that there is danger of infection ff)r a period about as long as this, and, besides, the patients are apt to be weakened from the effects of the disease, and not able to resist the strain of continuous mental effort. The safest plan is to main- tain quarantine until two successive cultures from the throat show absence of diphllioria bacilli. 42S TEXT-BOOK OF HYGIENE. DENGUE. The disease known as break-bone fever, dandy fever, and by vari- ous other names, was first discovered in the United States in 1780, by Dr. Benjamin Eush. Dr. Eush describes an epidemic wliich pre- vailed duritig the summer and early autumn of that year under the name of 'bilious remittent fever," but the symptoms of the disease hardly leave any doubt that it was dengue. In 1779 and 1780 it was also observed on the Coromandel coast, in Egypt, and on the island of Java. In 1784 to 1788 dengue also prevailed in various cities of Spain. In 1818 an epidemic appeared in Lima, in which nearly every one of the 70,000 inhabitants was attacked. In 1824-25 the disease again prevailed widely in India, where it was known as the "three-day fever." Isolated outbreaks occurred in that country until 1853, when it again appeared as a wide-spread epidemic, and in 1872 another epidemic outbreak occurred in the East, extending from Eastern Africa to Arabia, India, and China. In 1826 an epidemic of dengue appeared in Savanah, and in the following two years spread over the southern portion of the United States and the West Indies, reaching the northern coast of South America. In 1845 to 1849 the disease was observed in Eio Janeiro; in 1848 to 1850 in the South Atlantic and Gulf States. In 1854 it was observed in Southern Alabama, and in the same j^ear in the West Indies. In 1873 another epidemic appeared in the lower Mississippi Valley, and in 1880 an outbreak of some extent occurred in New Or- leans, Charleston, and other places on the Gulf and South Atlantic coasts. Dengue always begins in the summer or early autumn, and ceases abruptly with the advent of cold weather. It is almost exclusively limited to hot countries. It spreads with extreme rapidity wherever it appears. It is not contagious; the manner of its propagation is not known. The susceptibility to the disease appears to be almost universal; it frequently prostrates the majority of the inhabitants where an outbreak occurs. During the epidemic in Calcutta in 1871- 72, 75 per cent, of the population were attacked. In the United States similar epidemics have been repeatedly observed. Dengue is rarely fatal. It seems to be propagated through the atmosphere. No measures of prevention are known or available. EPIDEMIC INFLUENZA. Accounts of epidemic influenza can be traced back to the year 1173, when the disease was observed coincidently in Italy, Germany, EPIDEMIC INFLUENZA. 429 and England. It has prevailed epidemically, at varying intervals, to the present time. In the fourteenth century 3 epidemics are recorded ; in the fifteenth, 4; in the sixteenth, 7; in the seventeenth, 46. Of these, 15 were very extensive, some of them prevailing over both hemi- spheres contemporaneously. On the American continent influenza was first recorded in 1627, when it prevailed in New England, where it again broke out in 1625. Following this there is no notice of the disease in America until 1732, when an epidemic began in the New England States, which extended over the entire globe. Epidemics occurred during the remainder of the eighteenth century in 1737, 1757, 1761, 1767, 1772, 1781, 1789, and 1798. During the present century the disease has prevailed more or less extensively in this country at thirteen different times, the last epidemic of any considerable extent being in 1897. In November, 1889, an epidemic began in Eussia which rapidly spread throughout Northern Europe, reaching the United States about the beginning of 1890, recurring in 1891 and 1892. The epi- demic was complicated in many cases by pneumonia of a fatal char- acter. The disease manifested itself in two principal forms, the catarrhal and the nervous. Epidemics more or less severe, in char- acter have occurred since. A curious feature of epidemics of influenza is the coincident oc- currence of outbreaks of a somewhat similar affection among ani- mals, horses and dogs being especially attacked. Influenza is an acute, specific, infectious disease, not directly con- tagious. It is caused by a very minute bacillus first observed by Pfeiffer. The disease frequently appears over a large area of country almost simultaneously. Peculiarities of climate, season, meteorological conditions, geological formation, or racial characteristics have no ap- parent influence upon the causation or spread of the disease. It oc- curs more frequently in the winter and spring than during the summer or autumnal months. The investigation into the epidemic of influ- enza among horses, referred to in a previous chapter,^^ seems to indicate, however, that a moist and impure atmosphere intensifles the disease. No measures of prophylaxis can be indicated except avoidance of anything tending to depress the vital powers, as well as disinfection of the upper respiratory passages by the use of local antiseptics. ■'' Cliaptcr I, p. 29. 430 TEXT-BOOK OF HYGIENE. EPIDEMIC CEREBRO=SPINAL MENINGITIS. This disease was first recognized in Geneva in 1805. In the fol- lowing year it was noted in various places in the United States. Both in Europe and in this country localized outbreaks of the disease occurred between the dates above mentioned and 1816. At this time the disease seemed to die out altogether, but in 1823 it re-appeared in various parts of Europe and America. Cerebro-spinal meningitis appeared in 1857 in the southwest of France, and during the following ten years spread over a large part of the country. Algiers, Italy, Denmark, and Ireland were also visited by the scourge. In 1854 and 1861 Sweden experienced its ravages, and in 1859 Norway was invaded by the disease, which continued for nearly a decennium in the latter country. From 1860 to 1867 the disease prevailed in Holland, Portugal, Germany, Ireland, and Enssia. , After the termination of what may be called the first epidemic, in 1816, cerebro-spinal meningitis was not again observed in this country until 1842. In the eight years succeeding, it prevailed epi- demically throughout almost the whole United States. From 1861 to 1873 it was noted frequently in various parts of the country. Since the latter year the reports of its occurrence in this country have been limited to sporadic cases or localized outbreaks. Cerebro-spinal meningitis is an acute infectious disease, very fatal in its tendency. It is contagious. The disease is caused by a diplococcus discovered by Weichselbaum (Diplococcus intraceUularis meningitidis). Climate has no influence upon its origin, but season seems to stand in a positive relation to its causation. About three- fourths of the epidemics noticed have occurred during the winter and spring months. The disease seems to show no preference for peculi- arities of topographical or geographical formation. Overcrowding, overwork, and uncleanliness have an important influence in determin- ing an outbreak. It is especially a disease of youth and adolescence. Out of 975 cases occurring in New York only 150 were over 20 years of age, while of the remainder 665 were under 10. The prophylactic measures to be adopted against cerebro-spinal meningitis consist in careful attention to the sanitary conditions of dwellings and streets, avoidance of overwork and overcrowding dur- ing times of epidemic, isolation of the sick, and disinfection of the sick-room after the termination of the disease. SYPHILIS. 431 SYPHILIS. In the year 1494, Charles VIII of France, in command of a large army, invaded Italy, and early in the following year besieged Naples. During the investment of the city a very severe disease, characterized by ulcers on the genitals, violent pains in the head and limbs, and generalized cutaneous eruptions broke out among the be- siegers and spread rapidly throughout the army and civil population. On the return of the army to France, after the termination of the war, the disease rapidly spread throughout Europe, and the literature of the early part of the sixteenth century, both medical and lay, teems with references to it. From the locality and other circumstances connected with its epidemic appearance the disease acquired various names. Thus, the French called it morbus Neapolitmius, or mal d'ltalie, while the Italians termed it morbus Gallicus, or mala Franzos. At a very early period it was, however, clearly recognized that the disease was com- municated during sexual intercourse, and hence it was usually de- scribed in medical writings under the name lues venerea, while in the popular literature it still figured as the Frenchman's disease {morbus Gallicus) . The name syphilis was first used in a poem descriptive of the disease, written in 1521 by Fracastor, a physician of Verona. The extraordinary outbreak of the disease toward the end of the fifteenth century led to many speculations concerning its origin. As it attacked persons in all ranks and conditions of life, "sparing neither crown nor cross," in the words of a contemporary poet, the favorite explanation was that meteorological influences had much to do with its causation. Many ascribed it to the malign influence of the stars. The Neapolitans attributed it to the wickedness of their enemies, the French, while the latter laid the blame on the filth and immorality of the Italians. The Spaniards claimed that it had been imported from America by Columbus, whose first expedition re- turned to Europe in 1493. There are records, however, which prove that the disease already existed in Italy in the latter year. In other parts of Europe the Jews, who had been driven out of Spain by the terrors of the Inquisition, were accused of this, as of many other misfortunes which befell the people. When it was definitely estab- lished that the disease was communicated almost solely by sexual intercourse, the theory of its transatlantic origin became very popular. It is characteristic of human nature to refer the origin of troubles resulting from its own vices to some other source, if possible. This 432 TEXT-BOOK OF HYGIENE. theory of the American origin of syphilis is still held by some writers. Within a few years, Dr. Joseph Jones, of New Orleans, claims to have found evidences of syphilitic disease in the skulls and other bones from some of the prehistoric Indian mounds in Mississippi. These observations of Dr. Jones, have, however, not been verified by others. Although the first great epidemic of syphilis is clearly traceable to the period between the years 1493 and 1496, an examination of the older literature reveals many descriptions of disease which can only be explained by assuming them to refer to syphilis. The Old Testa- ment Scriptures contain numerous references to diseases of the genital organs. In most instances these troubles are ascribed to the wrath of God, although in some cases a pretty shrewd hint is given as to the causation of the affections. Finaly-^ remarks that the Hebrew word translated in all versions of the Bible by "flesh" signifies also the virile member. In this light, the references in Leviticus, XIII-XV; Numbers, XXV, 1-9, XXXI, 16-18; Deuteronomy, IV, 3; Joshua, XXII, 17; I Samuel, V, 6, 9, 12; Psalms CVI, 28-30; I Corinth- ians, X, 8; Ephesians, II, 11; and Colossians, II, 13, receive a new interpretation. Numerous innuendoes in the Latin classics, and more or less exact descriptions in the medical writings of Greece, Eome, China, and India, leave no room for doubt that venereal diseases, and probably among them syphilis, have existed from the earliest times. At the present day syphilis is the most widely prevalent of all contagious diseases. In 1873 Dr. F. E. Sturgis estimated that in New York 1 person out of every 18 suffered from it. This is con- sidered a moderate estimate. Dr. J. William White, of Philadelphia, pronounces the opinion that "not less than 50,000 people of all classes in that city are affected with syphilis." On this basis Gihon estimates the number of syphilitics in the United States at one time at 2,000,000.23 The disease is transmitted, in the vast majority of cases, during the performance of the sexual act, but there are numerous other ways in which it may be and frequently is communicated. In the special literature of the subject are records of many cases in which the dis- ease was acquired through a kiss, a bite, the act of suckling (from infant to nurse, and conversely), using a pipe, glass-blowers' mouth- piece, the finger of a midwife, the instrument of the dentist or sur- '^'Arch. f. Dermat. u. Syphilis, II Jahrg. 1 Heft., p. 126. ^The Prevention of Venereal Diseases by Legislation, Sanitarian, June, 1882. GONORRHEA. 433 geon, inoculation of syphilitic secretion mixed with saliva in the process of tattooing, and many other ways. Numerous cases have been reported where physicians were inoculated on the finger while examining a syphilitic patient. Eecent observations seem to show that the disease is caused by a spirillum — Spirocheta pallida. The prophylactic measures which suggest themselves from a con- sideration of the nature of .the disease are isolation of those infected, regular inspection of the class of persons through whom the disease is most frequently transmitted, i.e., prostitutes, and individual pre- cautions against acquiring it. Greater attention to cleanliness of the genital organs on the part of those indulging in promiscuous inter- course would aid largely in reducing the number of cases of syphilis. Eecent investigations by Metchnikoff show that syphilitic infec- tion may be prevented by the local use of a salve containing calomel, 33 grams; lanolin, 67 grams, and petrolatum, 10 grams. The appli- cation must be made within a few hours after coitus. Hypodermic injection of a solution of atoxyl (an arsenical preparation), in doses of 75 centigrams, followed by 60 centigrams, will prevent infection within two weeks. Fig. 47. — Micrococci Gonorrhea in Pus. (Park.) GONORRHEA. Gonorrhea is one of the venereal trio which is responsible for more misery, ill health, and "race suicide" than any other single sociologic factor. It has been estimated that fully 80 per cent, of cases of pelvic disease in women is caused by gonorrhea; 20 per cent, of blindness is due to gonorrheal infection of the new-bom; 50 per cent, of all involuntary chihlless marriages are attributed to the same cause. Fitfh asserts that of every one hundred women who 28 434 TEXT-BOOK OF HYGIENE. have married men formerly infected with gonorrhea, hardly ten re- main well. The disease is caused by a diplococcus {Micrococcus gotir orrliece or gonococcus) first observed by Neisser, in 1879. It is communicated through direct contact by sexual inter- course with individuals suffering from the disease, either in acute or chronic form. The chief source of infection is prostitution, and in considering prophylaxis we must deal with one of the most intricate social problems — the so-called "social evil." It is generally conceded that education of the young of both sexes in the danger lurking in promiscuous intercourse and a general dissemination of knowledge concerning sexual functions and venereal diseases will go far to- ward remedying the evil. It is claimed that an injection of a few drops of a 20 per cent, solution of protargol post-coitum will prevent infection. Blindness can be prevented by attention to the eyes of the new-born, and instillation into the eyes of one drop of a solution of silver nitrate, 2 grains to the ounce. The third member of the venereal group — the soft chancre, or chancroid — is a localized ulceration caused by a bacillus discovered by Ducrey, in 1890. The affection is communicated through sexual intercourse, and seems to be propagated under conditions of extreme uncleanliness. DISEASES OF ANIMALS COMMUNICABLE TO MAN. Sheep-pock. — This is a highly contagious and infectious disease of sheep, resembling, in its symptoms, course, and fatality, small-pox as it occurs in the human race. It is believed by Bollinger to be dif- ferent from the form of small-pox produced in sheep, goats, horses, and other animals by the inoculation of human small-pox. Sheep- pock can be inoculated upon other animals and man, but only pro- duces a local disease at the point of inoculation in the latter. Sheep may be protected against this disease by inoculation with sheep-pock virus (ovination), or by vaccination with vaccine Ij^mph. The pecu- liarity of sheep vaccinia is that it is a more or less generalized disease, the pustules being distributed over the body. Sheep-pock, when inoc- ulated upon human beings, does not produce a generalized infectious disease, but remains entirely local. Actinomycosis. — Veterinarians have frequently observed a dis- ease attacking the jaws of cattle and producing tumors, often with ulcerated surfaces. The bone is usually involved. The disease has heretofore been generally considered a sarcomatous growth. It is not seldom observed among the cattle in the western stockyards, where ANIMAL DISEASES COMMUNICABLE TO MAN. 435 it is known in the vernacular as "swell-head." Eecent investigations by Ponfick have shown that the growth consists of a vegetable para- site (actinoni3^ces), and that it is inoculable upon other animals, and may be conveyed to man. A considerable number of cases have been observed in human beings in Germany, where the disease was first described by Ponfick, and several cases have been reported in this country. Bovine Tuberculosis (Perlsucht). — In cattle, tuberculosis occurs in two forms, miliary tubercles and cheesy masses in the lungs, and firm, pearly nodules on the serous membranes. These nodules do not break down, but may become calcified. Bovine tuberculosis is a frequent disease among cows kept in Fig. 48. — Actinomyces liominis (Lung). X 350. damp, dark, and ill-ventilated stables. The disease, which is essen- tially the same as human tuberculosis, tubercle bacilli being present in the neoplasms, is believed to be transmissible to human beings by means of the milk or flesh of tuberculous animals. The sale of the meat of tuberculous cattle should be prohibited. Rabies. — Hydrophobia in the brute, and its communicability to man through a bite, has been known from the remotest antiquity. It occurs in dogs, foxes, wolves, horses, and other animals, and may be transmitted from any of them to human beings. The contagium of rabies, the infective poison, is contained prin- cipally in the saliva, and is usually inoculated by the teeth of the mad animal. 436 TEXT-BOOK OF HYGIENE. Pasteur has shown that the greatest virulence of the rabies poison resides in the brain and spinal cord of the animal suffering from the disease. By attenuation of this virus, the nature of which has not yet been definitely determined, its virulence could be dimin- ished, and by inoculation of men and animals with the attenuated virus protection against the disease could be secured. The fact seems likewise established that the period of incubation of the inoculation- rabies is much shorter than that acquired in the usual way by bites of rabid animals. Hence, inoculation with the attenuated virus protects the bitten individual against the fatal outbreak of the unmodified disease. Fig. 49. — Colony of Anthrax Bacilli^ slightly Magnified. (After Fliigge. ) Anthrax. — Anthrax, or splenic fever (milzbrand), is an acute, highly contagious and infectious disease of herbiverous animals, which may be transmitted by inoculation or the ingestion of the virus to other animals and to man. The disease is due to a minute vegetable organism which is found in the blood and tissues of the diseased animals. This organism. Bacillus antliracis, was first discovered by Pollender, and has been thoroughly investigated by Davaine, Pasteur, Koch, and others. Inoculation of these bacilli or their spores always produces the disease in susceptible animals. Skins of animals not infrequently contain the virus, which may then gain access to the blood of persons engaged in handling them. Knackers, butchers, wool-sorters, and ANIMAL DISEASES COMMUNICABLE TO MAN. 437 other persons liable to come in contact with sick animals, or hand- ling their flesh or hides, are subject to the infection, either by direct inoculation (through abrasions of the skin, etc.) or by inhalation of the spores of the bacillus. An intestinal form of anthrax in man, mycosis intestinalis, is sometimes produced by the consumption of meat of animals suffering, when killed, of splenic fever. Numerous instances have been reported. The diagnosis has been verified by dis- covering the bacillus of anthrax in the blood and various organs of the individuals attacked. In view of the dangerous character of the disease, persons coming in contact with animals suffering from anthrax should be warned of their peril. In order to protect other animals in a herd, strict isola- Fig. 50.— Bacillus Mallei. (Park.) tion of the infected, thorough disinfection of the stables occupied by them, and deep interment of the cadavers of those dead from the disease are indicated. The vaccination of animals with cultures of anthrax bacilli attenuated by being grown at 42° C. for twenty-four to forty-eight hours has been found to protect animals against infection. Glanders. — Glanders, or farcy, is a very fatal contagious disease of horses which may be communicated to other animals and to man. The cause of glanders has been discovered by Loffler to be a bacillus resembling the bacillus tuberculosis. Pure cultures of this bacillus, known as Bacillus mallei, were inoculated into animals, and followed by glanders in a number of the cases. The infection in man may occur either upon the seat of excoria- tions of the skin or mucous membranes, especially those of the nose, 438 TEXT-BOOK OF HYGIENE. conjunctiva, and possibly by inhalation of infective particles float- ing in the air. Animals with glanders should be promptly killed and their cada- vers cremated or deeply buried. No part of the body of any animal dead with glanders should be allowed to be used. Infected stables should be thoroughly disinfected. RESUME OF SOME OF THE INFECTIOUS DISEASES. The following brief summary of the more important infectious diseases will be found useful : — Abscesses. — Localized suppuration, caused principally by the so- called pyogenic cocci (staphylococci, streptococci, etc.), but may be caused by other bacteria (B. coli, B. typhosus). So-called "cold ab- scesses" are caused by the tubercle bacillus. The affection may be prevented by thorough sterilization of instruments and dressings which come in contact with a wound, as well as by rendering such wound free from germs. Laboratory diagnosis: Demonstration of germ in the pus. Actinomycosis. — Caused by a fungus, actinomyces hovis or ray fungus. It is a disease of animals communicated to man by way of the alimentary or respiratory tract or wounds. Prophylaxis includes the destruction of the abscesses. Laboratory diagnosis: Demonstra- tion of characteristic fungus in the discharges. Anthrax. — Caused by Bacillus anthracis. It is a disease of ani- mals communicated to man, and may be transmitted by direct contact or by insects, the consumption of flesh from the diseased animal (intestinal anthrax), or inhaling the dust from the hair of the in- fected animals (pulmonary anthrax, or wool-sorters' disease). The prophylaxis includes isolation of the diseased animals, the complete destruction of the carcasses, and vaccination of the exposed stock. Laboratory diagnosis: Demonstration of characteristic bacillus in the blood or point of infection. Cholera. — Caused by Spirillum cholerce. Transmitted by water and food, principally the former. The period of quarantine, one week. Prophylaxis consists in sterilizing the food and drink, and disinfection of the stools. Laboratory diagnosis: Cultivation of the spirillum from the feces. Diphtheria. — Caused by Bacillus dipMherice of Klebs-Loffler. Transmitted by direct contact, fomites, and air. Period of quarantine, until two successive cultures from the throat are negative. Prophyl- RESUME OF SOME INFECTIOUS DISEASES. 439 axis consists in isolation, disinfection of upper respiratory passages by mild antiseptics, immunization with antitoxin, disinfection of premises. Laboratory diagnosis: Cultivation of the Klebs-Loffler bacillus on blood serum, from the throat of suspected patients. Dysentery. — The bacillary form is caused by Bacillus shigce, the amebic form by Anieba dysenterice. Transmitted by water and food. Prophylaxis consists in disinfection of the stools and sterilization of food and drink. Laboratory diagnosis: The cultivation of the bacil- lus from the feces or the microscopic demonstration of the ameba. Glanders. — Caused by Bacillus mallei. Transmitted by inhala- tion of, or infection of wounds with nasal secretions and discharges from infected animals. Prophylaxis consists in disinfection of se- cretion and destruction of carcasses. Laboratory diagnosis: Injection of culture from secretion into guinea-pigs ; development of swelling of testicle is characteristic; to detect latent glanders, use mallein. Gronorrhea. — Caused by Micrococcus gonorrliece (gonococcus). Transmitted by sexual contact, rarely fomites. Prophylaxis consists in strict avoidance of promiscuous intercourse and local disinfection after such intercourse. Laboratory diagnosis: Demonstration of the gonococci in the discharge, or cultivation on serum-agar. Hydrophobia. — Caused by unknown micro-organism. Trans- mitted by bites of rabid animals. Prophylaxis consists in the destruc- tion of animals suffering from rabies and isolation of those bitten; cauterization of wound and Pasteur treatment. Laboratory diagnosis: Eeproduction of the disease by subdural inoculation into the lower animals ; demonstration of certain histological changes in the ganglia of suspected animals. Influenza. — Caused by Bacillus influenza of Canon and Pfeiffer. Transmitted by fomites and inhalation. Prophylaxis consists in iso- lation and disinfection of discharges. Laboratory diagnosis: Demon- stration of bacillus in the secretions from respiratory passages. Leprosy. — Caused by the Bacillus leprce. Believed to be trans- mitted by insects. Prophylaxis consists in isolation and destruction of insects and vermin. Laboratory diagnosis: Demonstration of the bacillus in the affected tissues. Malaria. — Caused by the Plasmodium malarice. Transmitted by mosquitoes (anopheles). Prophylaxis consists in destruction of mos- quitoes and prophylactic use of quinine. Laboratory diagnosis: Demonstration of the parasite in the blood, either fresh or stained, of the patient. Measles. — Supposed to be caused by a bacillus discovered by 440 TEXT-BOOK OF HYGIENE. Canon and Pielicke. Transmitted by direct contact and fomites. Period of quarantine, sixteen days. Prophylaxis consists in isola- tion, disinfection of fomites, skin, and secretions from nose and mouth, and final fumigation of sick-room. Mumps. — Cause unknown. Transmitted by direct contact. Period of quarantine, twenty-four days. Prophylaxis consists in iso- lation and disinfection of secretions from upper respiratory passages. Plague. — Caused by Bacillus pestis. Transmitted by rats, fleas, and inhalation of patient's sjiutum. Period of quarantine, ten days. Prophylaxis consists in isolation, destruction of rats and vermin, and disinfection of all discharges. Laboratory diagnosis: Demonstration of the bacillus in the pus from the buboes; animal inoculation. Pneumonia. — Caused by Diplococcus lanceolatus (pneumococcus). Transmitted by fomites. Prophylaxis consists in isolation and disin- fection of sputum. Laboratory diagnosis: Demonstration of the pneumococci in the sputum. Relapsing Fever. — Caused by Spirillum obermeieri. Mode of transmission obscure; possibly insects. Prophylaxis consists in the protection from bites of insects. Laboratory diagnosis: Demonstra- tion of the spirillum in the blood. Scarlet Fever. — Cause unknown. Transmitted by direct contact, fomites, milk. Period of quarantine, ten days after exposure; period of isolation of patient, about six weeks. Prophylaxis consists in isola- tion, disinfection of skin and fomites, and final fumigation of sick- room. Small-pox. — Cause unknown. Transmitted by direct contact and fomites. Period of quarantine, 16 days after exposure; period of isolation of patient, until disappearance of eruption. Prophylaxis consists in isolation, vaccination, disinfection of skin and fomites, and final fumigation. Syphilis. — Supposed to be caused by Spiroclieta pallida. Trans- mitted by direct contact (coitus, kissing) and fomites. Prophylaxis consists in disinfecting the mouth of patient and exclusive use of eating and drinking utensils. The patient should be enjoined from kissing and such contact with the well as would be liable to lead to infection. Physicians and dentists should be particularly careful not to infect themselves, and more especially not to become carriers of infection. Laboratory diagnosis: Demonstration of the spirochete in the lesions. Tetanus. — Caused by Bacillus tetani. Transmitted by infecting deep wounds with earth containing the micro-organism. Prophylaxis RESUME OF SOME INFECTIOUS DISEASES. 441 consists in free incision, cauterization, and injection of antitetanic serum. Laboratory diagnosis: Demonstration of the bacillus on the objects which caused the injury, by the aid of animal inoculations. Typhoid Fever. — Caused by the Bacillus typhosus. Transmitted through water, milk, food, and fomites, also by contact with infected feces. Prophylaxis consists in disinfection of stools and urine of patient as well as fomites; purification of polluted water-supply; sterilization of suspected food and drink; protection against flies. Laboratory diagnosis: Demonstration of the typhoid bacillus in the blood ; Widal test ; test of urine for diazo-reaction. Typhus. — Cause unknown. Transmitted by direct contact, fo- mites, and air. Period of quarantine, fourteen days; period of isola- tion, about four weeks. Prophylaxis consists in isolation and final fumigation. Tuberculosis. — Caused by Bacillus tuberculosis. Transmitted by inhalation of dried sputum, consumption of infected food. Prophy- laxis consists in disinfection of sputum and protection of food-supply. Final fumigation of premises. Laboratory diagnosis: Demonstration of the tubercle bacillus in the sputum or other discharges; the tuber- culin test. Whooping Cough. — Cause unknown. Transmitted by direct con- tact and by inhalation of ejected secretions. Prophylaxis consists in isolation, disinfection of sputum, and final fumigation of premises. Yellow Fever. — Cause unknown. Transmitted by bite of mos- quito (stegomyia fasciata). Period of quarantine, fourteen days after exposure. Prophylaxis consists in protection against mosquitoes. QUESTIONS TO CHAPTER XVII. HISTORY OF EPIDEMIC DISEASES. Of what advantage is the study of the history of epidemic diseases ? What are some of the most important maladies of this class? To what are they all due? What are some of the synonyms of the Oriental plague? What are some of its characteristic symptoms? What is the date of the first clear account of it? How long did this epidemic persist? When did it make its second incursion into Europe? What Avas one of the peculiar symptoms of this epidemic? What was its estimated mortality? What were some of its moral effects ? When was its final incursion into Western Europe ? What minor epidemics of it have there been since? When was the last, and where? Is it now endemic anywhere? To what was its origin formerly ascribed? What conditions are always present when the plague prevails? What is another evident factor in its causation? How is it generally transmitted? Is it a germ disease? What are the measures of prevention therefore indicated? What is the sweating sickness? What are some of its characteristic symptoms and peculiarities? What is evidently its nature? Is there any class exempt from it? What favors its spread? What relation has it to cholera? When did it first appear in England? When for the last time? Where has it appeared since? Have there been many outbreaks in Europe? What are the earliest details regarding small-pox? ^Vhen was it sup- posed to have been introduced into Europe? Who made the first distinct reference to it in medical literature? When? What was the estimated mor- tality from this disease in Europe previous to the introduction of vaccination? Where has it been very fatal in its devastations in recent years? What other countries and peoples have suffered from it? What is the mortality from unmodified small-pox? How is the disease transmitted? What factors are necessary to cavise an outbreak? Wliat may carry the poison? For what distance about a patient may the air be infectious? In what stages of the disease is it contagious? What races are more commonly attacked, and among which is it more fatal? Does one attack of small-pox always confer future immunity from the disease? Wherein is the popular belief, that persons suffering from an acute or chronic disease are less liable to incur small-pox than the healthy, at fault? Which maladies are most likely to afford this immunity? When does such immunity appear to cease? When do epidemics of small-pox usually begin? In what seasons do they spread most rapidly? Does the disease spread rapidly at first? Has the specific organism of small-pox been certainly discovered? When was the first attempt to limit the fatality of small-pox by inocu- lation made in Europe? When was the practice introduced into England, and (442) QUESTIONS TO CHAPTER XVII. 443 by whom? What were the details of the method as then practiced? What were the characteristics of the disease thus produced? Was the practice altogether without danger to the one inoculated? What other grave objec- tion was there to such inoculations? When was the practice of inoculation introduced into America, and by whom? How long was it continued in England and in America? Wliere was it practiced before its introduction into Europe ? What led to the discovery of vaccination? Who first practiced it? When? To whom is due the merit of demonstrating and publishing the value of vaccination? When did he perform his first vaccination, and with what results? When did he publish the first pamphlet in relation to it? When was vaccination introduced into America, and by whom? What is the relation of vaccinia (cow-pox) to small-pox? What are the symptoms produced in the case of a successful vaccination? When may the individual be considered to be thoroughly protected? Is the immunity absolute for life? ^Vliat is the character of an attack of small-pox in an individual who has once been vaccinated? Does repeated vaccination increase the immunity? What effect has vaccination had on the mortality from small- pox? On the prevalence of the disease? What important precaution should be observed in all vaccinations ? Why? When should children be vaccinated? When should they be revac- cinated? What are some of the peculiarities following upon revaccination ? What are some of the objections urged against humanized virus? Are these all valid? 'VlTiat are some of its advantages? How is it to be inoculated? How is animal virus obtained? How is it to be used? In what way do the results from using it differ from those of humanized virus? What complications are likely to occur in the course of the vaccinia? What are some of the causes of these complications? What subjects are unfavorable ones for vaccination? When may vaccination be properly de- layed? What diseases may be communicated by or may follow vaccination? What cases should be promptly revaccinated ? What besides vaccination is highly important in the prophylaxis of small-pox? What precautions should be observed in the care of one sick with small-pox? What are the best disinfectants for such cases? When is all danger of infection over? Where is Asiatic cholera endemic? What can be said of its ravages there? When were the first authentic accounts of it given? When did the disease first become epidemic outside of India? What were some of the countries visited? W^hen did it first appear in England? When and where in America? When did this outbreak from India end? When did it again become pandemic, and how long before it again reached the United States? What were the ports through which it entered? How long did it persist in this country? How long in South America? When was the next visitation to this country? What parts of South America were first invaded at this time? Where else was cholera raging during these periods, and where was it practically endemic? 444 TEXT-BOOK OF HYGIENE. When was the last serious impoi-tation of the disease into this country, and by what port did it enter? Where else, and when, have there been im- portant epidemics since this date? What does the history of all these epi- demics demonstrate? What factors must concur that there may be an epidemic ? What is the specific cause of cholera ? Who discovered it ? When ? Is the disease contagious? How is it spread? What conditions seem to be necessary for its propagation? When do outbreaks usually occur, and when do they subside? Why is the disease endemic in India? How do these con- ditions predispose the victims to the disease? Are these conditions peculiar to India? Where else may they exist? How is the specific organism given off from the human body? How does it usually gain entrance into others? What evidence is there of this (see chapter on Water) ? What other agencies may aid in disseminating the disease? What are the measures of prophylaxis against cholera? How can the entrance of the disease into a community be prevented? What measures of local sanitation may be even more eff"ective? Why? How shall the drinking- water and food be rendered harmless? How may one guard against an individual predisposition to cholera? What measure of personal prophylaxis is useful ? What is the rationale of this? What disease may simulate cholera during an epidemic, and to what is it often due? In times of cholera epidemics, what sanitary measures are to be estab- lished? What disinfectants are to be used? What articles are to be disin- fected, and how? What are some of the objections to the indiscriminate use of the bichloride of mercury? What may be used in its stead? What does Koch recommend, and what objection is there to its use? What plan should be pursued at the beginning of an epidemic? When was relapsing fever first described? \\Tien was it first observed in America? When did it last appear here? What predisposing conditions favor it? ^Vhat is its specific exciting cause? Where is the germ found? What are the preventive measures to be used against relapsing fever? How long has typhoid fever been known as a distinct disease? Where is typhoid fever common? When is it most prevalent? What persons and ages are most subject to it? To what is the disease due? Where is it found? Is the disease contagious? Where is the poison developed? Does it arise de novo? How may the poison be conveyed to human beings? What prophyl- axis may be employed against typhoid fever ? What are the requisites for prevention ? When were the earliest authentic accounts of typhus fever made? What predisposing conditions favor its development and spread ? When is it more prevalent? By what is it limited? Where is it apt to occur? What class of persons is most likely to be attacked? Is it contagious? How may it be prevented? What measures are to be pursued during an outbreak of the disease? QUESTIONS TO CHAPTER XVII. 445 Where is the present home of yellow fever? What localities are most liable to epidemics of this disease? What is the date of the first authentic account of it ? When and where did it first appear in the United States ? Has it ever originated here or been endemic? How many times has it been epidemic in this country in the last two centuries? When and where was the last epidemic? In what season do epidemics occur? In what climates may it be endemic? What climatic conditions seem to be necessary for an out- break? What is probably its specific cause? Has this been discovered? What is one of the principal factors in its spread? Is the disease contagious? How is the poison conveyed? What is necessary to the propagation of the disease? What preventive measures are to be employed against yellow fever? What is to be done, should the disease become epidemic in a city? Will this be efficacious in most cases? Who first distinguished between scarlet fever and measles? Which dis- ease is more prevalent? What countries have been practically exempt from scarlet fever ? When was scarlet fever first observed in America ? When do epidemics of measles usually begin? When of scarlet fever? What is the exciting cause of each disease, and how may it be conveyed? Have bad hy- gienic surroundings an influence in the propagation of either disease? What are measures for prevention in both cases? How old is the history of diphtheria ? When was it first observed in this country? When did it again prevail epidemically here? How are vari- ous epidemics marked? Is it contagious? How may it be conveyed? What is the exciting cause? Is diphtheria identical with croup? What plan should be pursued for prevention regarding the two diseases? Is diphtheria trans- missible to animals? What precautions should be taken with a person sick with diphtheria? How long should children who have had diphtheria, scarlet fever, small-pox, or measles be detained from school? Why? What is dengue? When and by whom was it first observed in the United States ? When does an epidemic begin, and when does it stop ? To what countries is the disease limited? Is it contagious? How is it propa- gated? Who are susceptible? What are the measures of prevention that may be employed? Is the disease fatal? What is the date of the earliest accounts of epidemic influenza? What are some of its synonyms ? When did it first prevail in America ? When was the last epidemic? How was this one complicated? Are animals subject to this disease? Is it contagious? How is it transmitted? When is it most prevalent? What are the measures of prophylaxis against it? When was epidemic cerebro-spinal meningitis first recognized? When did it appear in America? When was the first epidemic here? When the next? When the last? Is it contagious or infectious? What is its tendency? When is it most liable to occur? What influence has climate upon it? What factors seem to favor an outbreak? What ages are most subject to it? What is the prophylactic treatment? When and where does syphilis seem to have had its origin? Are there any traces of evidence of its existence before this? What can be said of its 446 TEXT-BOOK OF HYGIENE. comparative prevalence? How is it usually transmitted? In what other ways may it be conveyed? What prophylactic measures are indicated? \^niat are some of the serious diseases of animals communicable to man? What is sheep-pock, and what is its peculiarity when inoculated upon human beings ? What is actinomycosis? What are some of the synonyms? To what is it due? In what two forms does tuberculosis oecvir in cattle? Is it common among them? How is it related to human tuberculosis? How may it be transmitted to man? What precautions should be enforced to prevent this transmission? What is rabies? How is it transmitted? Where is the contagium con- tained? Where does the poison of greatest virulence reside? How may the virus be cultivated, and what changes take place in it? How may immunity against the disease be produced? Who discovered and advocated this method of inoculation? What is anthrax? What are some of its synonyms? To what is it due? How may it be transmitted? What are the measures of prophylaxis against it, both for man and animals ? Wiiat is glanders? To what is it due? How may infection occur? What should be done with animals sick with this disease? What else should be done? CHAPTER XVIII. ANTISEPTICS, DISINFECTANTS AND DEODORANTS. Much confusion exists in the poj)ular mind, and even among physicians, as to the exact meaning of the terms at the head of this chapter. By many they are used synonymously, and hence frequently give rise to ambiguity and misunderstanding. Antisepsis, which is so frequently confounded with disinfection, should be more accurately defined than is usual by writers. An anti- septic is an agent which retards, prevents, or arrests putrefaction, decay, or fermentation. It does not necessarily destroy the vitality of the organisms upon which these processes depend. An antiseptic may also arrest the development of the organisms which cause infectious diseases, and may hence be used as a preventive of such diseases. But antiseptics do not destroy the life of disease-germs, and hence cannot be relied upon when such organisms are present. By disinfection, in the proper and restricted use of the term, is meant the destruction of the specific infectious material which causes infectious diseases. If the view is accepted that all infectious diseases are due to micro-organisms or germs, then a disinfectant is equivalent to a germicide. In sanitary practice and experimental investigations this view is, in fact, adopted. In testing the action of various disin- fecting agents upon infectious material, the biological test is the one universally relied upon by experimenters, and no observations upon disinfection based upon chemical tests alone would be accepted by sanitarians as conclusive. It may therefore be assumed for practical purposes that no agent can be accepted as a disinfectant if it is not also a germicide. From this it follows that disinfection, to be trust- worthy, must be thorough. "There can be no partial disinfection of infectious material; either its infectious power is destroyed or it is not. In the latter case there is a failure to disinfect."^ Obviously, also, there can be no disinfection in the absence of infectious material. Fecal discharges, a diseased body or corpse, clothing, bedding, an apartment, a ship, or a hospital ward may or may not be infected. In the former case we may speak of disinfecting them; in the latter it would be an inappropriate use of the word. "•Roport of Committee on Disinfectants of the American PTiblic Health Association, p. 236. (447) 448 TEXT-BOOK OF HYGIENE. Confusion is also liable to arise by considering disinfectants and deodorizers as synonymous. Deodorants merely remove the offensive odors, and may not possess any disinfecting power whatever. Thus, one of the most efficient disinfectants at our command (mercuric chloride) is not a deodorizer at all, except by preventing putrefaction. On the other hand, some of the most effective deodorants have only a subordinate position in the scale of disinfectants. Careful investigations have sho'WTi that there is a wide divergence between various disinfecting agents in their influence upon disease- germs, some being efficient in high dilutions, while others require to be brought in contact with the germs in great concentration. For example, mercuric chloride will act as an efficient poison to certain disease-germs (anthrax spores) in the proj)ortion of 1 to 1000, while zinc chloride must be used in the proportion of 1 to 5 (or 30 per cent.). It has been further discovered that different disease-germs pre- sent varying resisting power to the same disinfecting agent, some being easily destroyed, while others are much more resistant. For example, the following table shows a number of experiments made by Dr. Meade Bolton for the American Committee on Disinfectants : — Table LVII. Organism. Chloride of Lime. Mercuric Chloride. Carbolic Acid. Typlioid bacillus Cholera spirillum .... Anthrax spores Staphylococcus aureus . . . Staphylococcus citreus . . Staphylococcus albus . , . 1 : 2000 1 : 2000 1:100 1:200 1:50 1:200 1 : 10,000 1 : 10,000 1:1000 1:100 1:100 1:50 (Uncertain.) 1:100 1:100 1:100 Assuming that infectious diseases are caused by micro-organisms, and that these are different from the micro-organisms of ordinary decay or putrefaction, it can be readily understood that the processes of organic decomposition may themselves act as disinfectants. It is known, for example, that when a fermenting liquid putrefies, the organisms of fermentation disappear and give place to the organisms of putrefaction (bacterium termo, etc.). So, likewise, the bacilli of anthrax and of tuberculosis are killed by the putrefactive process, if this takes place in the absence of free oxygen. Furthermore, the reproduction of organisms of a certain kind ceases when certain ANTISEPTICS, DISINFECTANTS AND DEODORANTS. 449 chemical changes take place in their environment. Fermentation in a saccharine liquid ceases and the ferment-organisms die when che accumulation of the product of the fermentation (alcohol) has reached a certain proportion, although there may still be undecom- posed sugar present. In like manner it is intelligible that the pro- ducts oi micro-organisms may eventually destroy their producers, and so place a limit to the morbid process. The specific cause of small- pox, yellow fever, cholera, and similar infectious diseases is rapidly destroyed when decomposition of the corpses of those dead with such diseases sets in. Hence, the reason why infectious diseases are not spread from cemeteries. From the foregoing it may be gathered that disinfection consists chiefly in a struggle against organized disease-germs.- As, how- ever, experiments and observations have shown that the life-history of disease-germs varies with the different organisms involved, it be- comes evident that specific directions concerning disinfection can be given only when the life-history of the specific organism is known. The American Committee on Disinfectants, to whose work refer- ence has already been made, divides disinfectants into two classes: those efficient for the destruction of infectious material containing spores, and those which will destroy infectious material only in the absence of spores. The recommendations of the committee, covering not only the appropriate disinfectant to be used for the destruction of the organisms, but also the conditions under which the agent should be used, are as follow : — - The most useful agents for the destruction of spore-containing infectious material are: — 1. Fire. Complete destruction by burning. 2. Steam under pressure. 105° C. (221° F. ) for ten minutes. 3. Boiling in water for half an hour. 4. Chlorinated lime.'' A 4-per-cent. solution. 5. Mercuric chloride. A solution of 1 to 500. For the destruction of infectious material which owes its infecting power to the presence of micro-organisms not containing spores, the committee rec- ommends: — 1. Fire. Complete destruction by burning. 2. Boiling in water for ten minutes. .3. Dry heat. 110° C. (230° F.) for two hours. 4. Chlorinaled lime.'' A 2-per-cent. solution. ^Mueller und Falk, in Roalcncycloposdie d. ges. Heilk., Bd. IV., p. 62. ^Sliould contain at IcaHt 25 per cent, of available chlorine. 29 450 TEXT-BOOK OF HYGIENE. 5. Solution of chlorinated soda.* A 10-per-cent. solution. 6. Mercuric chloride. A solution of 1 to 2000. 7. Sulphur dioxide. Exposure for twelve hours to an atmosphere con- taining at least 4 volumes per cent, of this gas in presence of moisture.^ 8. Carbolic acid. A 5-per-cent. solution. 9. Sulphate of copper. A 5-per-cent. solution. 10. Chloride of zinc. A 10-per-cent. solution. The committee would make the following recommendations with refer- ence to the practical application of these agents for disinfecting purposes: — For Excreta. (a) In the sick-room: — — 1. Chlorinated lime in solution, 4 per cent. In the absence of spores: — 2. Carbolic acid in solution, 5 per cent. .3. Sulphate of copper in solution, 5 per cent. fh) In privy -vaults : — 1. Mercuric chloride in solution, 1 to 500.* 2. Carbolic acid in solution, 5 per cent. fc) For the disinfection and dcodorization of the surface of masses of organic material in privy- vaults, etc.: — Chlorinated lime in powder. For Clothing, Bedding, etc. (a) Soiled underclothing, bed-linen, etc.: — 1. Destruction by fire, if of little value. 2. Boiling for at least half an hour. 3. Immersion in a solution of mercuric chloride of the strength of 1 to 2000 for four hours. 4. Immersion in a 2-per-cent. solution of carbolic acid for four hours. fb) Outer garments of wool or silk, and similar articles, which would be injured by immersion in boiling water or in a disinfecting solution: — 1. Exposure in a suitable apparatus to a current of steam for ten minutes. 2. Exposure to dry heat at a temperature of 110° C. (230° F. ) for two hours. * Should contain at least 3 per cent, of available chlorine. ^This will require the combustion of between 1% to 2 kilogrammes of sulphur for every 28 cubic metres of air-space. The vaporization of liquid sulphur-dioxide can be more accurately regulated. "The addition of an equal quantity of potassium permanganate as a de- odorant, and to give color to the solution, is to be recommended. ANTISEPTICS, DISINFECTANTS AND DEODORANTS. 45I (c) Mattresses and blankets soiled by the discharges of the sick: — 1. Destruction by fire. 2. Exposure to superheated steam (105° C. =221° F. ) for ten minutes. (Mattresses to have the cover removed or freely opened. ) 3. Immersion in boiling water for half an hour. Furniture and Articles of Wood, Leather, and Porcelain. Washing, several times repeated, with solution of carbolic acid, 2 per cent. For the Person. The hands and general surface of the body of attendants of the sick, and of the convalescents, should be washed with — 1. Solution of chlorinated soda diluted with nine parts of water (1 to 10). 2. Carbolic acid, 2-per-cent. solution. 3. Mercuric chloride, 1 to 1000. For the Dead. Envelop the body in a sheet thoi'oughly saturated with — 1. Chlorinated lime in solution, 4 per cent. 2. Mercuric chloride in solution, 1 to 500. 3. Carbolic acid in solution, 5 per cent. For the Sick=room and Hospital Wards. (a) While occupied, wash all surfaces with — 1. Mercuric chloride in solution, 1 to 1000. 2. Carbolic acid in solution, 2 per cent. (b) When vacated: — Fumigate with sulphur dioxide for twelve hours, burning at least 11/2 kilogrammes sulphur for every 28 cubic metres of air-space in the room; then wash all surfaces with one of the above-mentioned disinfecting solutions, and afterward with soap and hot water; finally throw open doors and win- dows and ventilate freely. For Merchandise and the Mails. The disinfection of merchandise and of the mails will only be required under exceptional circumstances; free aeration will usually be sufficient. If disinfection seems necessary, fumigation with sulphur dioxide will be the only practicable method of accomplishing it without injury. Rags. (a) Rags which have been used for wiping away infectious discharges should at once lie burnt-d. 452 TEXT-BOOK OF HYGIENE. fb) Rags collected for the paper-makers during the prevalence of an epidemic should be disinfected, before they are compressed in bales, by — 1. Exposure to superheated steam (105° C. = 221° F. ) for ten minutes. 2. Immersion in boiling water for half an hour. Ships. fa) Infected ships at sea should be washed in every accessible place, and especially localities occupied by the sick, with — 1. Solution of mercuric chloride, 1 to 1000. 2. Solution of carbolic acid, 2 per cent. The bilge should be disinfected by the liberal use of a strong solution of mercuric chloride. (b) Upon arrival at a quarantine station, an infected ship should at once be fumigated with sulphurous-acid gas, using li/4 kilogrammes of sul- phur for every 28 cubic metres of air-space; the cargo should then be dis- charged on lighters; a liberal supply of the concentrated solution of mercuric chloride (1 to 32) should be thrown into the bilge, and at the end of twenty- four hours the bilge-water should be pumped out and replaced with pure sea- water; this should be repeated. A second fumigation after the removal of the cargo is recommended. All accessible surfaces should be washed with one of the disinfecting solutions heretofore recommended, and subsequently with soap and hot water. For Railway=cars. The directions given for the disinfection of dwellings, hospital wards, and ships apply as well to infected railway-cars. The treatment of excreta with a disinfectant before they are scattered along tlie tracks seems desirable at all times, in view of the fact that they may contain infectious germs. During the prevalence of an epidemic of cholera this is imperative. For this purpose the standard solution of chlorinated lime is recommended. From the foregoing it would appear that heat, chlorinated lime, mercuric chloride, solution of chlorinated soda ( Laharraque's solu- tion), carholic acid, sulphate of copper, zinc chloride, and sulphur dioxide (sulphur fumes) are the most generally available disinfec- tants. The following "general directions" for the practical application of disinfection are given by the committee : — Disinfection of Excreta, etc.— The infectious character of the dejections of patients suffering from cholera and typhoid fever is well established; and this is true of mild cases an^ of the earliest stages of these diseases, as well as of severe and fatal cases. In cholera, diphtheria, yellow fever, and scarlet fever all vomited material should also be looked upon as infectious. And in ANTISEPTICS, DISINFECTANTS AND DEODORANTS. 453 tuberculosis, diphtheria, scarlet fever, and infectious pneumonia the sputa of the sick should be disinfected or destroyed by fire. It seems advisable, also, to treat the urine of patients sick with an infectious disease with one of the dis- infecting solutions below recommended. Chloride of lime, or bleaching powder, is perhaps entitled to the first place for disinfecting excreta, on account of the rapidity of its action. The following standard solution is recommended: — Dissolve chloride of lime (chlorinated lime, bleaching powder) of the best quality'' in pure wafer in the proportion of G ounces to the gallon (45 grammes to the litre). Use 1 quart (1 litre) of this solution for the disinfection of each dis- charge in cholera, typhoid fever, etc.« Mix well, and leave in the vessel for at least one hour before throwing into privy-well or water-closet. The same directions apply for the disinfection of vomited matters. Infected sputum should be discharged directly into a cup half full of the solution.^' A 5-per cent, solution of carbolic acid may be used instead of the chloride-of-lime solution, the time of exposure to the action of the disinfectant being four hours. Disinfection of the Person. — The surface of the body of a sick person or of his attendants, when soiled with infectious discharges, should be at once cleansed with a suitable disinfecting agent. For this purpose, solution of chlorinated soda (liquor sodee chlorinatte — Labarraque's solution) diluted with 9 parts of water, or the standard solution of chloride of lime diluted with 3 parts of water, may be used. A 2-per-cent. solution of carbolic acid is also suitable for this purpose, and under proper medical supervision the use of a solution of corrosive sublimate (1 to 1000) is to be 'recommended. In diseases like small-pox and scarlet fever, in which the infectious agent is given off from the entire surface of the body, occasional ablutions with the above-mentioned solution of chlorinated soda are recommended. In all infectious diseases the body of the dead should be enveloped in a sheet saturated with the standard solution of chlorinated lime, or with a 5-per-cent. solution of carbolic acid, or a 1 to 500 solution of corrosive sub- limate. Disinfection of Clothing. — Boiling for half an hour will destroy the vitality of all known disease-germs, and there is no better way of disinfecting clothing or bedding which can be washed than to put it through the ordinary operations of the laundry. No delay should occur, however, between the time of removing soiled clothing from the person or bed of the sick and its im- mersion in boiling water, or in one of the following solutions until this can be done: — 'Good chloride of lime should contain at least 2.5 per cent, of available chlorine. Eecently nascent chlorine for disinfecting purposes has been ob- tained on a large' scale by the electrolysis of sea-water. " For a very copious discharge use a larger quantity. "Rffcntly a small spitting-cup made of stiff paper has been iiitrodiiccd especially for' the use of consumptives. The cup is carried about by the patient or kc])t witliin reach. \Yhen the cup has been in use for a time, and licfor!! tlie sputa can bccoinc dcsiccafcil, it \^ liirown into the fire and burned. 454 TEXT-BOOK OF HYGIENE. Corrosive sublimate, 1 gramme to the litre (1 to 1000), or carbolic acid (pure), 8 grammes to the litre. The articles to be disinfected must be thoroughly soaked with the dis- infecting solution and left in it for at least two hours, after which they may be wrung out and sent to the wash.^" Clothing or bedding which cannot be washed should be disinfected by steam in a properly-constructed disinfection chamber. In the absence of a suitable steam disinfecting apparatus, infected clothing and bedding should be burned. Disinfection of the 8ick-room. — In the sick-room no disinfectant can take the place of free ventilation and cleanliness. It is an axiom in sanitary science that it is impracticable to disinfect an occupied apartment for the reason that disease-germs are not destroyed by the presence in the atmosphere of any known disinfectant in respirable quantity. Bad odors may be neu- tralized, but this does not constitute disinfection in the sense in which the term is here used. These bad odors are, for the most part, an indication of want of cleanliness or of proper ventilation, and it is better to turn con- taminated air out of the window or up the chimney than to attempt to purify it by the use of volatile chemical agents, such as carbolic acid, chlorine, etc., which are all more or less offensive to the sick, and are useless so far as disinfection — properly so called — is concerned. When an apartment which has been occupied by a person sick with an infectious disease has been vacated, it should be disinfected. The object of disinfection in the sick-room is mainly the destruction of infectious material attached to surfaces or deposited as dust upon window-ledges, in crevices, etc. If the room has been properly cleansed and ventilated while still occupied by the sick person, and especially if it was stripped of carpets and unnecessary furniture at the outset of his attack, the difficulties of disinfection will be greatly reduced. All surfaces should be thoroughly washed with the standard solution of chloride of lime, diluted with 3 parts of water, or with 1 to 1000 solution of corrosive sublimate. The walls and ceiling, if plastered, should be subse- quently treated with a lime-wash. Especial care must be taken to wash away all dust from window-ledges and other places where it may have settled, and thoroughly to cleanse crevices and out-of-the-way places. After this application of the disinfecting solution, and an interval of twenty-four hours or longer for free ventilation, the floors and wood-work should be well scrubbed with soap and hot water, and this should be followed by a second, more pro- longed exposur • to f re&h air, admitted through open doors and windows. As an additional precaution, fumigation with sulphurous-acid gas is to be recom'uended, especially for rooms which have been occupied by patients Avith small-pox, scarlet fever, diphtheria, typhus fever, and yellow fever. But fumigation with sulphurous-acid gas alone, as commonly practiced, cannot be relied upon for disinfection of the sick-room and its contents, including bed- ding, furniture, infected clothing, etc., as is popularly believed. ^ " Solutions of corrosive sublimate should not be placed in metal re- ceptacles, for the salt is decomposed and the mercury precipitated by contact with copper, lead, or tin. A wooden tub or earthen crock is a suitable re- ceptacle for such solutions. ANTISEPTICS, DISINFECTANTS AND DEODORANTS. 455 When fumigation is practiced, it should precede the general washing with a disinfecting solution heretofore recommended. To insure any results of value, it will be necessary to close the : partmsnt to be disinfected as com- pletely as possible by stopping up all apertures through which the gas might escape, and to burn not less than 3 pounds of sulphur for each 1000 cubic feet {IV2 kilogrammes to 28 cubic metres) of air-space in the room. To secure complete combustion of the sulphur, it should be placed, in the form of powder or small fragments, into a shallow iron pan, which should be set upon a couple of bricks in a tub partly filled with water, to guard against fire. The sulphur should be thoroughly moistened with alcohol before ignit- ing it." Disinfection of Privy-vaults, Cess-pools, etc. — When the excreta (not previously disinfected) of patients with cholera or typhoid fever have been thrown into a privy-vault this is infected, and disinfection should be resorted to as soon as the fact is discovered, or whenever there is reasonable suspicion that such is the case. It will be advisable to take the same precautions with reference to privy-vaults into which the excreta of yellow fever have been thrown, although we do not definitely know that this is infectious material. For this purpose the standard solution of chloride of lime may be used in quantity proportioned to the amount of material to be disinfected, but where this is eonsiderabl* it will scarcely be practicable to sterilize the whole mass.- The liberal and repeated use of this solution, or of a 5-per-cent. solu- tion of carbolic acid, will, however, disinfect the surface of the mass, and is especially to be recommended during the epidemic prevalence of typhoid fever or of cholera. All ex "osed portions of the vault, and the wood-work above it, should be thoroughly washed down with the disinfecting solution. Instead of the disinfecting solutions recommended, chloride of lime in powder may be daily scattered over the contents of the privy-vault. Disinfection of Ingesta. — It is well established that cholera and typhoid fever are very frequently, and perhaps usually, transmitted through the medium of infected water or articles of food, and especially milk. Fortunately, we have a simple means at hand for disinfecting such infected fluid. This consists in the application of heat. The boiling temperature maintained for half an hour kills all known disease-ge^-ms. So far as the germs of cholera, typhoid fever, and diphtheria are concerned, there is good reason to believe that a temperature considerably below the boiling-point of water will destroy them. But in order to keep on the safe side, it is best not to trust anything short of the boiling-point (100° C. = 212° F.) when the object is to disinfect food or drink which is open to the suspicion of containing the germs of any infectious disease. During the prevalence of an epidemic of cholera it is wall to boil all water for drinking purposes. After boiling, the water may be filtered, if necessary, to remove sediment, and then cooled with pure ice if desired. "Liquid anliydrous sulphur-dioxide may be used, and will probably give better results than combustion of sulphur. 456 TEXT-BOOK OF HYGIENE. In recent years formaldehyde gas has taken the place of sulphur for aerial disinfection of rooms, fomites, etc. The following is freely quoted from a circular issued by the Illinois State Board of Health : — Formaldehyde (otherwise known as methyl aldehyde, formic- aldehyde and "formalin") exists in several forms, but is principally known as gas. Its germicidal properties were not recognized until 1886, and were not put to use until 1890. The formaldehyde gas is the vapor of wood alcohol v,diich has undergone a chemical change. The gas is produced by passing the vapor of wood alcohol over plati- num or platinized carbon in an incandescent state. Many portable apparatus for the production of formaldehyde gas directly from wood alcohol have been devised during the past seven or eight years, but none have proved satisfactory. The aqueous solution of formaldehyde gas, known as formalde- hyde or formalin, is a 40-per-cent. solution of the formaldehyde gas in water. Many of the commercial preparations do not contain 40 per cent, of formaldehyde. The concentration of the solution can not exceed 40 ^er cent. This preparation, if properly made, is a pow- erful bactericide and is preferable to corrosive sublimate as a germi- cide, cost not considered, although it is much slower in action. Sev- eral processes have been devised for the liberation of formaldehyde gas from its watery solution. The solution when exposed to the air gives off a considerable quantity of the gas, especially when sprayed on large surfaces. If sprayed on b^.ankets or sheets, or articles of clothing, hung in the room or on the walls, the liberation of the gas will be so rapid as to compel the operator to leave the room. These facts have given rise to the belief that exposure of the gas in this manner will be sufficient to cause disinfection. The results, however, do not confirm this. There is much uncertainty as to the amount of gas which is evolved, and the behavior of the gas is at times very capricious. The most common method of obtaining formaldehyde gas from the watery solution at the present time is by means of apparatus designed to regenerate the gas by boiling the solution under pressure. Many generators operating on this principle are to be found on the market. Several of these are complicated machines requiring skill to properly operate. As some of the generators require constant atten- tion, it has been found necessary to place them outside of the apart- ment being disinfected and to pass the gas into the room by means of a tube nm through a keyhole. The diffusion of the gas produced in this way is slow, jjarticularly in large areas, tending to concentration ANTISEPTICS, DISINFECTANTS AND DEODORANTS. 457 at a few points and to the formation of paraformaldehyde. This method of disinfection cannot be recommended. With the Schering method of disinfection, which consists in the rapid evaporation of paraform pastilles, said to contain 100 per cent, pure formaldehyde, many tests have been made by the Illinois State Board of Health during the past five years. The results were gen- erally satisfactory, when the gases evolved were thoroughly mixed with the watery vapor. This method, however, is expensive; much care must be used in the working of the generator, and it has been found very difficult after disinfection to rid the premises of the gas. In one of the experiments the vapor ignited. The experiments were conducted with the Schering formalin disinfector (not the lamp) manufactured by Schering & Glatz, Xew York. Formaldehyde candles, which are composed of a variable amount of paraformaldehyde, pressed in cylindrical form in a tin container, are now ofi^ered to ^Dhysicians and health authorities as a means of disinfection. It is claimed that, by burning the paraform, the heat produced causes the solid to revert to the gaseous form. No depend- ence whatever should be placed on these candles. The evaporation of the solution of formaldehyde by means of heat in an ordinary kettle is one of the simplest methods of disin- fection with formaldehyde, and as a result has proven the most effective. This is termed the Breslau method. Many health authori- ties have testified to its efficiency during the past seven years. While the results obtained with some of the methods of formalde- hyde disinfection formerly suggested have been generally satisfactory, failures were at times experienced when the conditions were appar- ently ideal; while under unfavorable conditions of temperature and humidit}', ineffective disinfection was of frequent occurrence. Eecently an exceedingly simple method of generating the gas by pouring formaldehyde solution over the crystals of potassium perman- ganate in an open vessel has been suggested, arid gives promise of overcoming the objections which have stood in the way of the more general adoption of formaldehyde as a disinfecting agent. This method primarily offered the advantages of absolute simplicity in operation, requiring no special apparatus and no fire. In addition to this, exhaustive experimental work has demonstrated that, in prac- tical disinfection, the method is unusually efficient, the effectiveness seeming to depend less upon the conditions of humidity and tempera- ture than that of any other method. The only apparatus required is a large, open vessel, protected by 458 TEXT-BOOK OF HYGIENE. some non-conductive material to preserve the heat within. An ordi- nary milk-pail, set into a pulp or wooden bucket, will answer every purpose, although a special container, devised for physicians and health officers, will be found of considerable advantage. This con- tainer or generator consists of a simply constructed tin can witli broad, flaring top. -Its full height is 151/^ inches, the height to the flaring or funnel-shaped top being about 8 inches. The lower or round section is 10 inches in diameter, while the funnel is 171^ inches in diameter at the top. This container is made of a good quality of tin, is supplied with a double bottom with 14-inch air-space between the layers of tin, and is entirely covered on the outside with asbestos paper. The asbestos paper and double bottom serve to effectively retain the heat which is generated by the vigorous chemical reaction occurring within the generator and which is essential to the complete production and liberation of the gas. The special container can be made by any tinner of ordinary intelligence and costs but a few dollars. With the room sealed, as is essential to any form of aerial disin- fection, the crystals of potassium permanganate (S^/o ounces to each 1000 cubic feet of air-space) are placed in the container. Over this salt is poured "formalin" or the 40-per-cent. aqueous solution of for- maldehyde (1 pint for every 1000 cubic feet of air-space). The for- maldehyde gas is promptly liberated by the vigorous chemical reac- tion of the formalin and the potassic salt and rises from the generator in immense volume in the form of an inverted cone. It is conse- quently essential that all preparations be made in advance and that the operator leave the room at once on the combination of the two chemicals. The doors or windows of exit should be promptly closed and sealed and the room left closed for at least six hours. The results obtained by this method in experiments conducted in the laboratories of the Illinois State Board of Health, under vary- ing atmospheric conditions, and with a rather wide range of tempera- ture, prove the method peculiarly effective, while the simplicity of the operation, the small expense of the apparatus (in fact, its success- ful operation without apparatus of any kind, if necessary), and the moderate cost of operation serve to commend it. However, even this method is not entirely free from danger of fire. Dr. C. T. White, while experimenting on disinfection, observed that in some instances spontaneous combustion of the formaldehyde gas takes place after the addition of the formaldehyde to the per- ANTISEPTICS, DISINFECTANTS AND DEODORANTS. 459 manganate of potash. Mr. C. H. La Wall, who investigated this phenomenon, ascribes it to the rapid formation of heat in the pres- ence of organic matter, and suggests the employment of small quan- tities of permanganate, not over 4 to 8 ounces to a charge, placed in several containers surrounded with large cones containing water. There should be no flame in the room. The following substances are antiseptics, but in the strength given cannot be depended upon as disinfectants : — Table LVIII. Thymol 1 : 80,000. Bichloride of mercury 1 : 40,000. Oil of mustard 1 : 33,000. Acetate of alumina 1 : 6310. Bromine 1 : 5597. Picric acid 1 : 5000. Iodine 1 : 4000. Sulphuric acid 1 : 800-1 : 3353. Permanganate of potassium 1 : 3000. Camphor 1 : 2500. Eucalyptol ' 1 : 2500. Chromic acid 1 : 2200. Chloride of aluminum 1 : 2000. Hydrochloric acid 1 : 1700. Benzoic acid 1 : 1439. Quinine 1 : 1000. Boric acid 1 : 200-1 : 800. Salicylic acid 1 : 200-1 : 800. Carbolic acid : 1 : 500. Sulphate of copper 1 : 400. Nitric acid 1 : 400. Biborate of soda 1 : 200. Sulphate of iron 1 : 200. Creasote 1 : 200. Arsenious acid 1 : 100. Pyrogallic acid 1 : 62. Tr. chloride of iron 1 : 25. Alcohol 40 to 95 per cent. The agents mentioned in the above list may all be used with satisfactory results in surgical and obstetrical practice as antiseptics, hut it must be borne in mind that the great danger in treating wounds comes from carrying infectious particles to them in the hands or in- struments of the operator. In order to render these aseptic the most tboroiigh measures of disin feed ion, such as heat, strong chemical dis- 460 TEXT-BOOK OF HYGIENE. infectants, and physical as well as chemical and biological cleanliness are indicated. In a surgical wound, or in the vagina and uterus of the parturient woman, the use of antiseptics is entirely secondary to dis- infection, under which may primarily be understood rigid cleanliness. In public and private sanitation, antiseptics have, as in prac- tical surgery, a subordinate importance. Deodorizers are sometimes useful in sanitary practice, but care must be taken not to look upon deodorization as equivalent to disin- fection. Among the most useful deodorizers are chloride of zinc, chloride of lime, permanganate of potassium, and a number of the agents mentioned in Table LYIII. QUESTIONS TO CHAPTER XVIII. ANTISEPTICS, DISINFECTANTS, AND DEODORANTS. What is an antiseptic? How may it be used? Is it necessarily a dis- infectant? Why? Is a disinfectant an antiseptic? Why? Why must disin- fection be thorough to be of any value? What is necessary that there may be disinfection? How is the term often popularly, but incorrectly, used? What is the essential difference between a disinfectant and a deodorant? What is a germicide? What is the true test of the value of a disinfectant? Have deodorants as such any real sanitary value? How do disinfectants differ in relation to disease-germs? How do the latter differ in relation to the former? How may the products of putrefaction, fermentation, or decay act as disinfectants? How may the products of the disease-germs themselves act as antiseptics or disinfectants? How may disinfectants be classified? What are the most useful agents for destroying spore-containing infectious material? How should these be used? What do we call disinfection by fire or heat? What agents may be used to disinfect infectious matter not containing spores? Which are most efficacious? What is an essential factor in the successful use of all disin- fectants ? In what diseases may the excreta be infected? What disinfectants may be used for excreta in the sick-room? In cess-pools? Why is mercuric chlo- ride not so efficacious here? What is the objection to the use of carbolic acid in typhoid fever? Why is chlorinated lime such a valuable disinfectant? How much chlorine should it contain? How should it be prepared? What is "milk of lime," and what value has it as a disinfectant for excreta? How may soiled underclothing, bed-linen, etc., be disinfected? How long shovild clothing be boiled in order to thoroughly disinfect it ? How may cloth- ing that would be harmed by immersion or chemicals be disinfected? What will be the effects on clothing of chlorine and stilphur gases? How may mat- tresses, blanketSj etc., be disinfected? How long should the active process require ? What are some of the best disinfectants for use on the person? How may the danger of infection from a case of scarlet fever, small-pox, etc., be lessened? How should the bodies of those dead of infectious diseases be cared for? What can be done in the way of disinfection during the occupancy of the sick-room? What are the only disinfectants available? What value will deodorants have here ? What method is to be followed as soon as the sick- room is vacated? Describe in detail. How may suspected merchandise and the mails be purified? What treatment should rags, etc., undergo? What is the method prescribed for the disinfection of a ship? For railway-cars? (See chapter on Quarantine.) How may articles of food and drink be made sterile and safe for use? How are antiseptics and disinfectants to be used, and for what purpose, in surgical and obstetrical practice? What is formaldehyde? What is the usual method of using formalde- hyde? What is the best method? (461) CHAPTER XIX. VITAL STATISTICS. The registration of vital statistics comprises the recording of the births, marriages, deaths, and diseases of a city, State, or nation. The facts thus secured must be properly classified and studied, for in no other way can a knowledge of the health of the inhabitants of such communities be obtained, and a real test is thus also furnished of the actual efficiency of sanitary undertakings. We may, indeed, study disease both by observation and experiment, thus learning that some maladies are more preventable than others and discovering their causes and means of jDrevention ; and it is also true that for smaller or special communities, such as armies, navies, schools, or special classes of workmen, the health status may be obtained by direct methods but for large communities this is clearly impracticable, and the sanitarian is obliged to depend upon the census and the above- mentioned registration. The census is the count of its population which every civilized country makes at certain intervals, its returns also including particu- lars as to age, sex, race, occupation, etc. From the sanitarian's standpoint the age-record is, next to the population, the most im- portant return, for the death-rate varies most according to age. In this country the census now furnishes various data for localized "san- itary districts," which may be even smaller than city wards, and these data afford the basis of comparison for variations in different parts of the same city and at different periods. The records of births, marriages, deaths, and diseases are obtained from the registration bureau, having been furnished the latter by duly authorized persons. The duty of registration should devolve upon the sanitary administration, such as the local or State board of health, this being the most appropriate medium for the collection of the information in question, while the individual returns should obviously be made to the bureau by the attending physician in each case. And, as these returns should be as accurate as possible, espe- cially as regards the diagnosis of preventable diseases and the deter- mination of the causes of death, both primary and secondary, it is one of the reasons why the State should carefully determine the (462) VITAL STATISTICS. 46?> qualifications of the physicians whom it allows to practice within its confines. From a sanitary point of view, the most important object of a registration of vital statistics is to "give warning of the undue increase of disease or death presumed to be due to preventable causes, and to indicate the localities in which sanitary efi^ort is most desirable and most likely to be of use."^ It should be remembered that the following fundamental prin- ciples that underlie all statistical inquiries must be considered in the examination and analysis of any records or reports of the kind in question :— 1. The numerical units with which the inquiry has to do must be constant, definite, and precise in character; if any lack these qualities, such should be omitted altogether. Hence the care that should be observed in the diagnosis of all cases. 2. Groups of the numerical units must be so arranged that no unit is in more than one group at a time, and so that there can be no question as to the group in which each unit belongs. This is com- paratively simple where the grouping regards only the age, sex, race, etc., but the difficulty increases with the complexity of facts and re- quires special talent to properly analyze and develop all possible features. 3. There must be a standard to express the relation of each group to the sum of the individual unit. This is usually 100, 1000, or some multiple of either. 4. The relation of each group to the total units is not a con- stant one unless all the factors which govern that relation are fixed and invariable — a condition which obviously does not obtain in vital statistics. The limit of variation in the relation of the component groups to the total, in two or more similar series, may, however, be expressed mathematically, and the variation itself will be found to diminish as the sum of individual units increases. Thus if, in the formula m -\- n = q, m be the number of units in one group and n the number in the other, the limit of variation will be indicated by the expression 2 "^ '^-^- ; or, again, the relative value of two or more series is as the square root of the number of units in the respective series. The arithmetical mean is often used in vital statistics, and this ' J. S. Billinf,'H, "Rej^istration of Vital Statistics," American Journal of the Medical Sciences, vol. Ixxxv, p. 37. 464 TEXT-BOOK OF HYGIENE. will always approximate the invariable if the number of units is sufficient, but it must be remembered that the relation expressed by the average in one case cannot be predicated positively of any other. As Dr. Guy says, "Averages are numerical expressions of probabilities ; extreme values are expressions of possibilities." The grajihic representation of statistical results is of advantage, since it brings their salient features clearly before the attention of the observer. The numerical units with which we are cencerned in vital statis- tics are persons, either living or dead, and these are divided into groups, according to age, sex, race, etc. Populations tend naturally to increase, the natural increment being measured by the difference in the number of births and deaths ; but the actual increment depends upon how this is modified by the relation between immigration and emigration. If these factors were all constant, the population would increase in geometrical progression; but as this is not so it cannot be exactly determined for periods other than those in which the cen- sus is taken. However, in determining the population for years other than census years, it is customary to assume that the same rate of increase continues as prevailed between the last two censuses, and to calculate the population therefrom by means of geometrical pro- gressions or logarithms. The number of houses in a city will help to determine the approximate population, for the average number of persons to the house in any city remains about the same from year to year. Such counts, as well as police censuses, are, however, almost always too high. In small and slowly-growing districts one-tenth of the difference in population of the last two censuses may be taken for each year since the last census. The population is always counted and annual birth- and ^eath- rates calculated in this country for the middle of the year. REGISTRATION OF BIRTHS. The collection of data for an accurate registration of births is much more difficult than the record of deaths. Instead of requiring physicians and midwives in attendance at the confinement to report births, it would be more equitable and probably more effectual to com- pel the parents, under penalty for failure, to record the birth of each child at the board of health. The items usually included in birth returns are: date and place of birth, sex and color of child, names of father and mother, parents' nativity and age, and father's Registration of diseases. 465 occupation. Sometimes the residence of the mother, number of chil- dren previously borne by the same mother, whether the child is legitiniate or not, and various other details are also added. It is evi- dent that for sanitary purposes most of' this information is entirely irrelevant. It seems to the author that, for the purpose of the sani- tarian and medical statistician, the date and p^ace of birth, sex and color 01 the child, and age, nativity, and occupation of both parents are sufficient. REGISTRATION OF MARRIAGES. The record of marriages is of no interest to the sanitarian. If, however, the registration could be made by a competent medical man, and the physical condition of the contracting parties noted, valuable deductions might be made in time, especially if the parties themselves and their offspring could be kept under observation for many years. This, however, is so manifestly impracticable that it barely deserves notice in this place. REGISTRATION OF DISEASES. As has been seen in Chapter XIX, a large class of diseases are communicable from one individual to another, either directly, by contact, or mediately, by infection. In large communities it is there- fore important that the sanitary authorities should possess informa- tion of the presence and prevalence of these diseases, in order that measures may be instituted for their restriction. It is true that in most cases the registration of deaths gives but too mournful evidence of the more fatal of the diseases of this class, but destructive epi- demics could probably be frequently averted if preventive measures could be enforced early. Besides, in the case of dengue and epidemic influenza the death-rate may be so small that, if the registration of deaths were alone depended upon, no evidence whatever might be attainable of the epidemic prevalence of such diseases. The registration of prevailing diseases is, therefore, one of the most important duties of the registrar of vital statistics. Prompt notices of all cases of infectious, miasmatic, or contagious diseases coming under their professional notice should be required of all physicians. It is unquestionably just, however, that the physicians required to perform this duty should be properly compensated by the public, whose interests they serve. 30 466 TEXT-BOOK OF HYGIENE. REGISTRATION OF DEATHS. The data entered upon the record of death should comprise the name, age, sex, color, nativity, descent, occupation, and civil con- dition of decedent, with date, place, and cause of death. Under, the heading "Descent" the birthplace of each parent should be given. Occupation should be accurately specified. The place of death should indicate the exact locality (number of street) where it occurred. Both proximate and predisposing causes of death should be entered, and any complications which may have influenced the fatal termina- tion should be noted on the record. The record should be in the possession of the local health author- ity before a permit for the burial of the deceased is granted. If this is not insisted upon, the report will soon be omitted and the registra- tion become defective. In fact, any system that puts off the collecting and recording of the death returns until the end of the year will fail to register from 25 to 40 per cent, of the number. DEATH=RATE AND BIRTH=RATE. In order to calculate the annual- death-rate of a place two facts are required to be known : first, the acutal or estimated population (generally obtained, as indicated, from the census), and, second, the number of persons who died in the district during the year. The number of deaths is divided by the population, which gives the death- rate for each individual for the year. To find the death-rate per 1000 the rate as found above is multiplied by 1000. Thus, the total number of deaths in the city of Philadelphia during 1893 was 23,- 655, and the estimated population 1,115,562. The death-rate for the year was 21,20 per 1000, obtained as follows: — 23.655 X 1000 — '- = 21.20 per M. 1,115,562 To calculate the annual death-rate per 1000 of a place from the returns for one week, the weekly population is first ascertained and then the number of deaths for the week divided by the weekly popu- lation and the quotient multiplied by 1000. The following example will render this clear : — The exact number of weeks in a year is 52.17747. The total population is divided by this number, giving the weekly popiilation. This gives for Philadelphia, assuming the above estimate to be correct, a weekly population of 21,381. For the week ending June 3, 1893, DEATH-RATE AND BIRTH-RATE. 467 the deaths in that city numbered 388. The annual death-rate per 1000 — that is to say, the number of deaths in each 1000 of popula- tion, if the same rate be maintained throughout the year — is ob- tained as follows: — 388 X 1000 =18.15 per M. 21,381 The daily death-rate is obtained in a similar manner, the divisor for obtaining the daily population being 365, 24226, and the monthly population is found by multiplying the daily population by the num- ber of days in the respective months. But it should be remembered that these rates for such short periods cannot by any means accurately indicate the actual annual rate, and that they are to be used only for comparing the rates for similar periods at different seasons, etc. ; otherwise, with such large populations and such short periods the probabilities of error are too great for the results to be of any value. The annual zymotic or infectious death-rate, or that for any one disease, is obtained in the same manner as the general annual death- rate, and likewise the birth-rate. Or, to find the annual death-rate per 1000 of population for this class of diseases, the following calculation may be made. Thus, out of the above 388 deaths, 84 were from in- fectious diseases: — 84 X 1000 =3.93 per M. per annum. 21,381 Or, if the percentage of deaths from infectious diseases be de- sired, the procedure would be as follows : — 84 X 100 = 21.65 per cent, of the total deaths. 388 As an exception to the rule, the rate of infant mortality or in- fantile death-rate is indicated by the ratio of deaths of children under one year to the number of births recorded for the year, and is found by multiplying the number of infantile deaths by 1000 and dividing by the number of births; for example, for the year just quoted the decedents under one year of age numbered 5710; the total number of births for the same year was 30,737. Hence — 5710 X 1000 ^I^ = 185.77 per 1000 births. Nineteen of the 388 deaths for the week ending June 3, were of colored persons. The death-rate of these to the total population is found in a similar manner to the above; but if it is desired to asccr- 468 TEXT-BOOK OF HYGIENE. tain the death-rate of the colored population alone, the v.^eekly colored population must first be obtained, and the rate calculated from this by the above formula. There are a number of factors that affect the general death-rate, such as the size of the community, habits of life, age- and sex- dis- tribution, occupation of the bulk of the inhabitants, etc. For the country and small towns the rate should be from 9 to 16 per 1000, gradually increasing until for the largest cities it amounts to from 18 to 21 per 1000. Death-rates reported below these figures would indicate that all the deaths had not been recorded, or that the popula- tion had been overestimated; rates above would be evidence that there vrere special causes at work demanding sanitary investigation and improvement. Among the causes that make the mortality among infants and children high are parents too young or sickly, hereditary taints, un- healthy environments, improper and insufficient food and clothing, and, not rarely, infant life-insurance. It is simply the manifestation of one of the workings of the law of "the survival of the fittest." In localities newly settled, where the proportion of adults to children is greater than the normal, the death-rate is naturally lower ; though it is conceivable that the occupations in which the adults engaged and the vicissitudes and unsettled conditions, both sanitary and social, of a new settlement might cause or tend to cause a very high mortality. Since more males die than females, the sex-distribution will also have its influence on the death-rate, especially if there is a prepon- derance of one sex over the other in any locality. Many conditions affect the death-rate from the different diseases, namely, age, race, sex, occupation, environment, seasons, temperature, etc. The zymotic death-rate, and especially that part of it due to typhoid fever, may be an extremely good index of the actual value and benefit of sanitary improvements and the enforcement of hygienic lav/s. Thus, the mortality from typhoid fever in England and Wales has been reduced more than 50 per cent, since the introduction and enforcement of the general sanitary regulations in that kingdom. On account of lack of registration of all cases of disease, it is practically impossible to determine the sick-rate of a community or population; but it is said that the sickness of a community amounts to the disablement of one person for two years for every death, and the records of English beneficial societies seem to show that each member averages about one and one-half weeks' sickness annually. The following definitions are introduced because the terms are DEATH-RATE AJND BIRTH-RATE. 469 frequently used in discussions of vital statistics, and especially of life- insurance. The comparative mortality figure indicates that the same number of persons that gave 1000 deaths in the whole population would furnish the deaths indicated by the figure in the city or locality in question. Thus, if the comparative mortality figure of a place is 925 and the death-rate of the country is 20, there are 1000 deaths for every 50,000 of the whole population and the death-rate of the given place is 18.5. For 20 : 1000 : : a; : 925 and x = 18.5. The average or mean age at death is ascertained by adding up the ages of all the decedents and dividing the sum by the number of deaths. Unless it is derived from the life-tables of an entire gen- eration, it is not a fair index of longevity or of sanitary conditions, since it is affected considerably by the age-distribution of the popula- tion from which it is compiled. The expectation of life at any age is the average number of years which persons of that age may expect to live. For the newborn it is the same as the mean duration of life, and, "as applied to commu- nities, it is the mean life-time of a generation of persons traced by the life-table method from birth to death, and is the only true test of the health of populations." A life-table is computed from the number and ages of the living and of those that die, these factors being ob- tained from the average population for each age and sex, and from the total death-returns between two or more censuses. It is, as Dr. Farr says, "a barometer which indicates the exact measure of the duration of life under given circumstances, and is indispensable in gauging the influence of sanitary or insanitary conditions." It is only when the population does not vary as to age- or sex- distribution that the mean duration of life is identical with the aver- age age at death. Otherwise, for any person at any age it is the same as the expectation of life. The probable duration of life is equivalent to the age at which any number of newborn children will be reduced one-half, the same conditions persisting. With a million children as a basis, it is less than forty-five years for males and about forty-seven years for females. It will be evident, on a little thought, that there must be many sources of error in calculations based upon such uncertain data as are derived from the registration of births and deaths as conducted in most cities in this country. Besides, the subject of vital statistics is essentially abstruse, and requires no little readiness in mathematics to appreciate its profounrlor bearings. Hence, in the foregoing chapter, no attempt has been made to penetrate beyond the imme- diate practical aspects of the questions involved. QUESTIONS TO CHAPTER XIX. VITAL STATISTICS. What is comprised in the registration of vital statistics? How are they to be made of use? Of what value are the recorded statistics to the sanitarian? How else may disease be studied? Why may not the same methods of deter- mining the general health be applied to large communities as to small ones? What is the census? What returns of interest to the sanitarian does it make? Which of these are the most important? Why? What is the advantage of furnishing returns for "sanitary districts," and what is meant by the latter? What returns are to be obtained from the registration bureau? Who furnishes these returns? Who should have charge of the registration? Why? Why should physicians make the returns? Why should the State take care in the licensing of physicians to practice? What is the most important object of the registration of vital statistics ? What are the fundamental principles underlying all statistical inquiry? What units or cases should be omitted? What renders the classification of groups difficult? What is the usual standard of comparison? When is the relation of component groups to the total constant? How may the probable limit of variation be determined? What tends to make the arithmetical mean approach the invariable? How may the relative value of different series of the same kind of cases be determined? What is the difference between aver- ages and extreme values ? Of what value is the graphic method of representing statistical results ? What are the units of vital statistics? How may they be divided into groups? What is the natural increment of a population? How does this differ from the actual increment? If the factors were constant, how would a population increase? Why? Why cannot the population be determined exactly for intercensal periods? What is the usual and most accurate way of determining it? How else may it be estimated? What is the fault of counts made by local authorities or police censuses? At what time of the year is the count always made? For what time are annual death-rates, etc., calculated? Why is the collection of data for birth-records difficult? Who should make the return? What items are usually included in the returns? Which are the only ones of value to the sanitarian and medical statistician? Why is the record of marriages of no sanitary interest? How might it be made so? Is this practicable? ^^Tiat classes of diseases should be reported and recorded? Why? ^Vllat epidemic diseases might escape notice by the statistician if only reported in death-returns? When should the returns of infectious diseases be made? Should there be any recompense for the returns to the physicians? (470) QUESTIONS TO CHAPTER XIX. 471 What data should be given by a death-certificate? Which items should be accurately specified? What care should be taken in reporting the cause of death? When should the burial-permit be issued? What factors are required in order to calculate the death-rate of a locality? How is the death-rate for the year obtained? How may the annual death-rate of a place be calculated from the death-returns for one week ? What is the weekly and the daily population? How is the monthly population found? What is the objection to rates determined from returns for such short periods? Of what value are they? What is meant by the zymotic or infectious death-rate? How may it be determined? How is the percentage of deaths due to infectious disease determined? How is the rate of infant mortality determined? What factors aflfect the general death-rate ? What is a fair death-rate for small communities? For large' cities? What do higher rates than this usually indicate? What do lower ones? What causes make the mortality so high among infants and young children. What may make the death-rate of a community lower than the normal? What higher? How may sex-distribu- tion affect the death-rate? What conditions or factors affect the mortality from the different diseases? How may the zymotic death-rate be an index of the value of sanitary measures? Why is it so difficult to determine the sick-rate of a community? How may the total amount of sickness be approximately estimated? What is meant by the comparative mortality figure ? What by the aver- age age at death ? Is this necessarily a fair index of longevity ? What affects it? What is meant by the expectation of life? Of what value is it when applied to communities? What is a life-table, and how is it computed? Of what value is it to sanitarians? When is the mean duration of life identical with the average age of death ? What is meant by the probable duration of life? Why are calculations of vital statistics liable to be unreliable or in- accurate ? CHAPTER XX. QUARANTINE. By quarantine is meant the adoption of restrictive measures to prevent the introduction of diseases from one country or locality into another. The term itself conveys no definite idea, being derived through the Italian from the Latin "quadraginta/' meaning "forty" and implying forty days — the period of detention imposed on vessels by the first quarantines established at Venice in 1403. The old sig- nificance of the term is entirely lost in its present application, which is quite general. Thus, besides regular maritime quarantine, mention is often made of land, railroad, cattle, shot-gun, house, and even room quarantine. The name of a disease or article of merchandise may be used in a prefix, as in "yellow-fever quarantine," small-pox, cholera, or rag quarantine. Moreover, quarantines are described as properly be- ginning at the port of departure, and as quarantine of inspection only, the fumigation and detention being imposed at some neighboring station. The term, therefore, is applied not only to establishments, but indifferently to persons, animals, diseases, localities, and measures. There is need of a clear understanding with regard to the term, for when, as occasionally, quarantine is ridiculed, or the assertion is made that the English disbelieve in quarantine, a wrong impression Avill be received, unless it is understood that only particular and obsolete forms of quarantine are meant, and not quarantine in the broad sense Just mentioned. The subject admits of two natural divisions — maritime and land quarantine; but before describing them attention is called to the following table, containing a list of diseases that are ordinarily found in official quarantine proclamations: — This list illustrates the growth of the sanitary idea and belief in quarantine. For many years, as now at some ports, the list was limited to yellow fever, typhus, cholera, and small-pox. It was thus limited at Boston prior to 1881, since which date diphtheria, scarlet fever, typhoid fever, and measles have been added. The statutes of New York define as quarantinable "yellow fever, measles, cholera, typhus or ship fever, small-pox, scarlatina, diphtheria, relapsing fever, and any disease of a contagious, infectious, or pestilential character (472) FOREIGN QUARANTINE. 473 Table LIX. Quarantinable Diseases. Disease Plague Yellow fever . . Cholera Tj'phus fever. . Small-pox Measles Diphtheria . . . Typhoid fever. Scarlet fever . . Relapsing fever Dengue Leprosy Period of Incubation, in days Shortest Longest Usual Authority and Remarks 14 21 20 14 10 28 Weeks 7 10 3 to 5 oi -ij 2 to "-4 5 to 14 10 10 2 to 5 21 4 to 7 6 5 Kitasato. Da Costa, Bartholow, Reed, Caiver. Bartholow. Br i stow. Da Costa. Da Costa. Bartholow. Bartholow. Da Costa. Bartholow. Barthiilow. Undetermined. which shall be considered by the health officer dangerous to the public health." At Gibraltar, the English sanitary authorities include dengue and epidemic rose-rash among the diseases subject to their quarantine regulations. Another addition to the list in this country is leprosy, to prevent the introduction of which, and in accordance with a resolution of the American Public Health Association, a prohibitory circular was issued by the Surgeon-General of the Marine-Hospital Service, December 23, 1889. Other diseases which may properly call for quarantine are mumps, whooping cough, chicken-pox, epidemic dysentery, glanders, tetanus, beriberi, epidemic influenza, and pulmonary tuberculosis. Influenza may be considered quarantinable under certain circum- stances, a successful quarantine being reported by Dr. Trudeau, whose cottage sanitarium, in the Adirondacks, New York, was thus kept exempt during the epidemic of 1890. With regard to pulmonary tuberculosis the ground is taken by the writer that this disease, at least among immigrants, should be excluded from the United States by quarantine. FOREIGN QUARANTINE. The object of maritime quarantine being protection against the importation of contagious or infectious disease, chiefly from abroad, 474 TEXT-BOOK OF HYGIENE. through the medium of vessels, their crews, passengers, and cargoes, it is most logical that restrictive measures should begin at the port of departure. Following are the regulations prepared by the Surgeon- General of the Public Health and Marine-Hospital Service of the United States and promulgated by the Secretary of the Treasury, April 1, 1903. All quarantine regulations are subject to occasional revision under the Act of Congress approved February 15, 1893. QUARANTINE REGULATIONS. QUAEANTINABLE DISEASES. 1. For the purpose of these regulations the quarantinable dis- eases are cholera, yellow fever, small-pox, typhus fever, leprosy, and plague. ' Foreign Eegulations. Quarantine Regulations to be Observed at Foreign Ports and at Poets in the Possessions andDependencies of the United States. Bills of Health. 2. Masters of vessels departing from any foreign port, or from any port in the possessions or other dependencies of the United States for a port in the United States or its possessions or other de- pendencies, must obtain a bill of health, in duplicate, signed by the proper officer or officers of the United States as provided for by law, except as provided for in paragraph 4. The following form is prescribed: — Form No. 1937. United States Bill of Health. Name of vessel, . Nationality, . Rig, . Master, . Tonnage, gross, ; net, . Iron or wood. Number of compartments for cargo, ; for steerage passengers, ; for crew, . Name of medical officer, . Number of officers, . Number of members of officers' families, . Number of crew, including petty officers, . Number of passengers, cabin, . Number of passengers, steerage, . Number of persons on board, all told, . Port of departure, . Where last from, . Number of cases of sickness and character, during last voyage. FOREIGN QUARANTINE. 475 Vessel engaged in trade, and plies between and ■ — . Sanitary condition of vessel, . Nature, sanitary history, and condition of cargo, , Source and wholesomeness of water supply, . Source and wholesomeness of food supply, . Sanitary history and health of officers and crew, . Sanitary' history and health of passengers, cabin, . Sanitary history and health of passengers, steerage, . Sanitary history and condition of their effects, . Prevailing diseases at port and vicinity, . Location of vessel while discharging and loading— open bay or wharf, . Number of cases and deaths from the following-named diseases during the past two weeks: Yellow fever — — Asiatic cholera Cholera nostras or cholerine Small-pox Typhus fever Plague Leprosy Number of cases of sickness and character of same while vessel was in this port, — . Any conditions affecting the pviblie health existing in the port of departure or vicinity to be here stated, . I certify that the vessel has complied with the rules and regulations made under the act of February 15, 1893, and that the vessel leaves this port bound for , U. S. of America, via . Given under my hand and seal this day of , 190 . ( Signature of consular officer : ) , 3. Vessels clearing from a foreign port or from any port in the possessions or other dependencies of the United States for any port in the United States, its possessions or other dependencies, and entering or calling at intermediate ports, must procure at all said ports a sup- plemental hill of health in duplicate signed by the proper officer or officers of the United States, as provided in the law. If a quarantin- able disease has appeared on board the vessel after leaving the original port of departure, or other circumstances presumably render the ves- sel infected, the supplemental bill of health should be withheld until such sanitary measures have been taken as are necessary. The following form is prescribed : — Supplemental Bill of Health. Port of . Vessel , bound from to , U. S. A. Sanitary condition of port, . 476 TEXT-BOOK OF HYGIENE. State diseases prevailing at port and in surrounding country, . Number of cases and the deaths from the following-named diseases during the past two weeks: — Table LX. Table of Diseases. Diseases No. of Cases No. of deaths Remarks (Any condition affecting the public health existing in the port to be stated here.) Yellow fever Asiatic cholera . . . . Cholera nostras, or cholerine Small-pox Typhus fever Plague Leprosy Number and sanitary condition of passengers and crew landed at this port. Cabin, No. . Sanitary condition and history, . Steerage, No. . Sanitary condition and history, . Crew, No. . Sanitary condition and history, . Note. — If disembarked on account of sickness state disease, . Number and sanitary condition of passengers and crew taken on at this port, and sanitary condition of effects. Cabin, No. . Sanitary condition and history, . Steerage, No. . Sanitary condition and history, . Crew, No. . Sanitary condit'on and history, . Sanitary condition of effects, . Sanitary history of vessel since leaving last j)ort. (Cancel Form A, B, or C, as the case requires.) Form. A. — To the best of my knowledge and belief — ] I no quarantinable disease has f appeared aboard since leav- (Form A will be used at intermediate ports where the vessel dues not enter and clear.) B. — I have satisfied myself that — (Form B will be used at intermediate porls where J the vessel enters and clt ars. ) C. — Since leaving the following quarantinable disease has appeared on board , and I certify that the necessary sanitary measures have been taken. I certify also that with reference to the passengers, effects, and cargo taken on at this port, the vessel has complied with the rules and regulations made under the act of February 15, 1893. Given tmcer my hand and seal this day of , 190 . ( Signature of consular officer : ) , FOREIGN QUARANTINE. 477 4. Under the act of Congress approved August 18, 1894, vessels pl3dng between Canadian ports on the St. Croix Eiver, the St. Law- rence Eiver, the Niagara River, the Detroit Eiver, the St. Clair Eiver, and the St. Mary's Eiver, and adjacent ports of the United States on the same waters; also vessels plying between Canadian ports on the following-named lakes, viz,, Ontario, Erie, St. Clair, Huron, Superior, Eainy Lake, Lake of the Woods, and Lake Champlain, and ports in the United States; also vessels plying between Mexican ports on the Eio Grande Eiver and adjacent ports in the United States, are exempt from the provisions of section 2 of the act granting additional quar- antine powers and imposing additional duties upon the Marine-Hos- pital Service, approved February 15, 1893, which requires vessels clearing from a foreign port for a port in the United States to obtain from the consular or medical officer a bill of health. During the prevalence of any of the quarantinable diseases at the foreign port of departure, vessels above referred to are hereby required to obtain from the consular officer of the United States, or from the medical officer of the United States, when such officer has been detailed by the President for this purpose, a bill of health, or a supplemental bill of health, in duplicate, in the form prescribed by the Secretary of the Treasury. Inspection of Vessels Leaving Foreign Ports and Ports in tire Pos- sessions or other Dependencies of the United States for Ports in the United States or its Possessions or other Dependencies. 5. The officer issuing the bill of health shall satisfy himself, by inspection, if necessary, that the conditions certified to therein are true, and is authorized, in accordance with the law, to withhold the bill of health or the supplemental bill of health until he is satisfied that the vessel, the passengers, the crew, and the cargo have complied with all the quarantine laws and regulations of the United States. 6. Inspection is required of — (a) All vessels from ports at which cholera, 3^ellow fever, or plague prevails, or at which small-pox or typhus fever prevails in epidemic form. (h) All vessels carrying steerage passengers; but need only in- clude the inspection of such passengers and their living apartments, if sailing from a healthy port. 7. Inspection of the vessel is such an examination of the vessel, cargo, passengers, ei-ew, personal cff'ects of same, including examina- tion of manifests and other papers, food- and water- supply, the as- 478 TEXT-BOOK OF EYGTENE. certainment of its relations Avith the shore, the manner of loading, and possibilities of invasion by small animals as will enable the inspecting officer to determine if these regulations have been complied with. 8. When an inspection is required, it should be made by daylight, as late as practicable before sailing. The vessel should be inspected before the j)assengers go aboard, the passengers just before embarka- tion, and the crew on deck; and no communication should be had with the vessel after such inspection except by permission of the officer issuing the bill of health. Requirements ivilh Regard to Vessels. 9. Vessels, prior to stowing cargo or receiving passengers, should be mechanically clean in all parts, especially the hold, forecastle, and steerage ; the bilges and limbers free from odor and deposit. The air streaks should be sufficient in number and open for ventilation. 10. Any portions of the vessel liable to have been infected by any communicable disease should be disinfected before the issuance of the bill of health. 11. The air-space, ventilation, food- and water- supply, hospital accommodations, and all other matters mentioned therein promotive of the health and comfort of the passengers must be in accordance with the provisions of the act of Congress approved August 2, 1882, entitled "An act to regulate the carriage of passengers by sea." 12. At ports Avhere cholera prevails in epidemic form, special care should be taken to prevent the water- and the food- supply from being infected. The drinking-water should be boiled and the food thoroughly cooked and protected against contamination by flies, etc. 13. At ports where yellow fever prevails, in addition to the other measures presented hereafter, ^precautions should be taken to prevent the introduction of mosquitoes on board the vessel. Water-tanks, water-buckets, and other collections of water about the .vessel should be guarded in such a manner that they shall not become breeding- places for mosquitoes. Measures should also be taken to destroy mosquitoes that may have come on board. Baggage destined directly or indirectly for any State should be disinfected at the request of the health officer of said State. All baggage from such ports must be rigidly inspected and the exclusion of mosquitoes assured. 14. At ports or places where plague, prevails, every precaution must be taken to prevent the vessel becoming infected through the agenc)'' of rats, ants, flies, fleas, or other animals. At such ports or places the vessel should not lie at a dock, or tie to the shore, or anchor FOREIGN QUARANTINE. 479 near any j^lace where such animals may gain access to the vessel. In case cables are led to the shore they should be freshly tarred and provided with inverted cones or such other devices as may prevent rats and other animals passing to the ship. The introduction of vermin on board the vessel from lighters and all other sources should be guarded against. In such ports sulphur fumigation should be resorted to in the holds when empty and from time to time during loading in order to destroy vermin. 15. At all infected ports or places, communication between the vessel and shore should be reduced to a minimum. 16. Vessels carrying passengers from any port or place where quarantinable disease prevails in epidemic form should have one med- ical officer; and from ports where cholera or plague prevails in epi- demic form should have two medical officers if more than 350 passen- gers are carried. Cargo. 17. Earth, loam, soft or porous rock should not be taken as bal- last at ports infected with cholera or plague. Street-sweepings, city cleanings, or anything containing organic refuse should not be taken as ballast from any port. Where practicable, hard rock or clean beach sand or sea-water ballast should be given preference. 18. Household goods, personal effects, bedding, and second-hand articles generally, coming from a district known to be infected with cholera, small-pox, typhus fever, or plague, or as to the origin of which no positive evidence can be obtained, and which the consular or medical officer has reason to believe are infected, should be disinfected prior to shipment. Measures should be taken with articles of this class from districts infected with yellow fever to insure their freedom from mosquitoes. 19. New merchandise in general may be accepted for shipment without restriction, and articles of new merchandise — textile fabrics and the like — which have been packed or prepared for shipment in an infected port or place, with a special view to protect the same from moisture incident to the voyage, may be accepted and exempted from disinfection. 20. Certain food products, \\%., unsaltcd meats, sausages, dressed poultry, fresh butter, fresh milk (unsterilized), fresh cheese, coming from cholera-infected localities or through such localities, if exposed to infection therein, should not be shipped. Fresh fruits and vege- tables, from districts where cholera prevails, shall be shipped only 480 TEXT-BOOK OF HYGIENE. under sucli sanitary supervision as will enable the inspector to certify t:liat they have not been exposed to infection. 21. All rags and textile fabrics used in the manufacture of paper and for other purposes which are collected, packed, or handled in any foreign port or place, with the exceptions as hereinafter specified, shall, prior to shipment to the United States, be subjected to disinfec- tion bygone of the prescribed methods. (Jute bags or bagging used in baling cotton, old rope, new cotton, or linen cuttings from factories not included.) The disinfection of the articles mentioned above shall be performed under the supervision of a United States consul or a medical officer of the United States, and a certificate in duplicate, signed b}' said consul or medical officer, shall be issued with each con- signment of same, v\-hich certificate shall identify the articles and state that they have been disinfected in accordance v>'ith the United States quarantine regulations. The original certificate of disinfection shall be attached to the consignee's invoice, and where the articles are car- ried by sea the duplicate certificate of disinfection shall be attached to the bill of health issued to the vessel conveying the same. Excepiions. — Such articles shipped from the dominion of Canada directly to the United States shall be exempt from this requirement if accompanied by affidavits demonstrating to the satisfaction of the collector of customs at the port of arrival that they have actuar.y originated in Canada and have not been shipped from a foreign country to Canada, and thence shipped to the United States ; and further, that the port or place where collected or handled has been free from quar- antinable diseases for thirty days prior to shipment. 23. Xew feathers for bedding, human and other hair (unmanu- factured), bristles, wool, hides not chemically cured, coming from a district where cholera or plague prevails, shall be refused entry into the United States until thirty days have elapsed since last exposure in case of cholera, and sixty days in case of plague, unless unpacked and disinfected. Feathers which have been used should be disinfected, and invariably by steam. Bristles which have been Ijoiled, and wool and new feathers which have been packed in naphthalin preparatory to shipment, may be shipped without further treatment. Dry hides packed in naphthalin may be shipped as chemically cured hides. Unsalted green hides from a district where cholera prevails must not be shipped. 23. The articles enumerated in the preceding paragraph coming 1 FOREIGN QUARANTINE. 481 from a district where small-pox, typhus fever, cholera, or plague pre- vails in epidemic form, should be refused shipment unless disinfected as hereinafter provided. 24. jSTothing in these regulations shall be construed to modify or affect in any way any existing restrictions promulgated by the secre- tary of the Treasury at the instance of the Bureau of Animal Industry, Department of Agriculture, regarding the importation of hides of neat cattle. 25. Any covering, shipped from or through an infected port or place, and which the consul or medical officer has reason to believe infected, should be disinfected. 26. Any article presumably infected, which can not be dis- infected should not be shipped. Passengers and Crew. 27. Passengers, for the purposes of these regulations, are divided into two classes : cabin and steerage. 28. When practicable, passengers should not ship from an infected port. 29. No person suffering from a quarantinable disease, or scarlet fever, measles, diphtheria, or- other communicable disease, should be allowed to ship. 30. Steerage passengers and crew coming from cholera-infected districts should be detained five days in suitable houses or barracks located where there is no danger from infection, and all baggage disinfected. 31. Steerage passengers and crew from districts not infected with cholera, shipping at a port infected with cholera, unless passed through without danger of infection and no communication allowed between such persons and the infected locality, should be treated as those in the last paragraph. 32. Cabin passengers coming from cholera-infected districts em- barking at a clean or an infected port should produce satisfactory evidence as to their exact places of abode during the five days imme- diately preceding embarkation. And if it appears that they or their baggage have been exposed to infection, the baggage should be disin- fected and the passengers detained under medical supervision a suffi- cient time to cover the period of incubation since last exposure. 33. Steerage passengers and crew who, in the opinion of the inspect- ing officer, have been exposed to the infection of yellow fever, should 4S2 TEXT-BOOK OF HYGIENE. be held under medical observation in a place free from danger of infection for a period of five da3^s before embarkation. 34. Steerage passengers and crew, coming from districts where small-pox prevails in epidemic form, or who have been exposed to small-pox, should be vaccinated before embarkation, unless they show evidence of having acquired immunity to small-pox by previous attack or recent successful vaccination. 35. Steerage passengers and crew who, in the opinion of the in- specting officer have been exposed to the infection of typhus fever, should not be allowed to embark for a period of at least twelve days after such exposure and the disinfection of their baggage. 36. Steerage passengers and crew who, in the opinion of the in- specting officer, have been exposed to the infection of plague should be held under medical observation in a place free from danger of infection for a period of seven days before embarkation, and their baggage disinfected. 37. Cabin passengers coming from plague-infected districts, whether embarking at a clean or an infected port, should produce satisfactory evidence as to their exact places of abode during the seven days immediately preceding embarkation. And if it appears that they or their baggage have been exposed to infection the baggage should be disinfected and the passengers detained under medical supervision a sufficient time to cover the period of incubation since the last ex- posure, 38. Should quarantinable disease appear in the barracks or houses in which passengers are undergoing detention, no passenger from said houses or barracks who has been presumably exposed to this new infection shouM embark until after the expiration of the period of incubation of the disease in question subsequent to the last expostire to infection and the application of all necessary sanitary measures. 39. All baggage of steerage passengers destined for the United States should be labeled. If the baggage is in good sanitary condi- tion the label shall be a fed label bearing the name of the port, the steamship on which the baggage is to be carried, the word "passed" in large type, the date of inspection, and the seal or stamp of the consular or medical officer of the United States. All baggage that has been disinfected shall bear a yellow label, upon which shall be printed the name of the port, the steamship upon which the baggage is to be carried, the word "disinfected" in large type, the date of disinfection, and the seal or stamp of the consular or medical officer of the United FOREIGN QUARAXTIXI';. 4H^i INSPECTION CARD. [Immigrants and Steerage Passengers.] Port of departure Date of departure Name of ship . Last permanent residencs Name of immisrrant Inspected and passed [Seal or stamp of consular or medical officer.] Passed at quarantine, port of United States. Passed by Immigration Bu- reau, port of [Date.] [Bate. [The following to be filled in by ship's surgeon or agent prior to or after embarkation.] Ship's list or manifest . No. on ship's list or manifest Berth No. a B-Sa (N CO -^ VACCINATED. [Signature or Stamj).] [Reverse Side.] Keep this Card to avoid detention at Quarantine and on Railroads in the United States. Diese Karte muss aufbewahrt werden, um Aufenthalt an der Quaran- tine, sowie auf den Eisenbahnen der Vereinisrten Staaten zu vermeiden. Cette carte doit etre conservee pour eviter inie detention a la Quaran- taine, ainsi que sur les chemins ds fer des Etats-Unis. Deze kaart moet bewaard worden, ten einde oponthoud aan de Quar- antijn, alsook op de ijzeren wegen der Vereenigde Staten te vermijden. Conservate questo biglietto onde evitare detenzione alia Quarantina e sulle Ferrovie degli Stati Uniti. Tento llstek musite uschovati, nechcete-li ukaranteny (zastavenf oliledng zjistOni zdravf) neb na drflze ve spojenych statech zdrzeni byti. Tuto kartocku trcba trimat' u sebe aby sa predeslo zderzovanu v karanterie aj na zeleznici ve Spojench StAtoch. 484 TEXT-BOOK OF HYGIENE. States. It is understood, and it will be so printed on the blank, that the label is not valid unless bearing the consular or medical officer's stamp or seal. 40. Each steerage passenger shall be furnished with an inspection card (see page 483). This card, stamped by the consular or medical officer, is to be issued to every member of a family as well as to the head thereof. ' 41. In a port where any quarantinable disease prevails, the per- sonnel of vessels should remain on board during their stay in such port. 42. Passengers and crews, merchandise and baggage, prior to shipment at a noninfected port, but coming from an infected locality, should be subject to the same restrictions as are imposed at an in- fected port. Eecords, Eeports, Etc. 43. The officer making the inspection will preserve in his office a record of each inspection made and of each immunity certificate given; a copy of each certificate of disinfection and of each bill of health issued. A weekly report of the transactions of his office shall be for- warded to the Surgeon-General at Washington, D. C. 44. In addition to the duties prescribed, the medical officer when detailed in accordance with the act of Congress approved February 15, 1893, shall furnish such reports to the Surgeon-General of the Public Health and Marine-Hospital Service as he may be able to make upon sanitary conditions and other matters affecting the public health and the welfare of the Service administration. Requirements at Sea} 45. The master of a vessel should observe the following measures or. board his vessel: — (a) The water-closets, forecastle, bilges, and similar portions of the vessel liable to harbor infection should be disinfected and fre- quently cleansed. (&) Free ventilation and rigorous cleanliness should be main- tained in all portions of the ship during the voyage and measures taken to destroy rats, mice, fleas, flies, roaches, mosquitoes, and other vermin. (c) A patient sick of a communicable disease should be isolated ^ These requirements are largely advisory in character, but it is never- theless true that a careful compliance with them should tend, at the port of arrival, to largely relieve the stringency of quarantine measures. FOREIGN QUARANTINE. 485 and one member of the crew detailed for his care and comfort, who, if practicable, should be immune to the disease. (d) Communication between the patient or his nurse and other persons on board should be reduced to a minimum. (e) Used clothing, body linen, and bedding of the patient and nurse should be immersed at once in boiling water or in a disinfect- ing solution. (/) The compartment from which the joatient was removed should be disinfected and thoroughly cleansed. Articles liable to con- vey infection should remain in the compartments during the disin- fection when gaseous disinfection is used. (g) Any person suffering from malaria or yellow fever should be kept under mosquito bars and the apartment in which he is confined closely screened with mosquito netting. All mosquitoes on board should be destroyed by burning pyrethrum powder (Persian insect powder) or by fumigation with sulphur. Mosquito larvge (wigglers or wiggle-tails) should.be destroyed in water-barrels, casks, and other collections of water about the vessel by the use of petroleum (kero- sene) ; where this is not practicable, use mosquito netting to prevent the exit of mosquitoes from such breeding-places. (Ji) In the case of plague, special measures must be taken to de- stroy rats, mice, fleas, flies, ants, and other vermin on board. (i) In the case of cholera, typhoid fever, or dysentery, the drink- ing water should be boiled and the food thoroughly cooked. The dis- charges from the patient should be immediately disinfected and thrown overboard. 46. An inspection of the vessel, including the steerage, should be made by the ship's physician once each day. 47. Should cholera, yellow fever, small-pox, typhus fever, plague, or any other communicable disease appear on board ship while at sea, those who show symptoms of these diseases should be immediately isolated in a proper place ; the ship's physician should then immedi- ately notify the captain, who should note same in his log, and all of the effects liable to convey infection which have been exposed to infec- tion should be destroyed or disinfected. 48. The hospital should be disinfected as soon as it becomes vacant. 4'.}. The dcfid should 1)0 enveloped in a sheet saturated with one of the strong disinfecting solutions, without previous washing of the body, and at once buried at sea or placed in a coffin hermetically eealed. 486 TEXT-BOOK OF HYGIENE. 50. A complete clinical record should be kept by the ship's sur- geon of all cases of sickness on board, and the record delivered to the quarantine officer at the port of arrival. 51. The following disinfecting solutions are recommended for use at sea : — Formulce for strong disinfecting solutions. BiCHLOKIDE OF MERCURY. (1:500.) ♦ Bichloride of mercury 1 part Sea water 500 parts Mix. Carbolic Acid. (5 per cent.) Alcohol 50 parts Carbolic acid, pure 50 parts Mix. Then add fresh water 900 parts ^ Formulce for weak solutions. BiCHLOKIDE OF MeRCUBY. (1:1,000.) Bichloride of mercury 1 part Sea water 1000 parts Carbolic Acid. (2% per cent.) Carbolic acid, pure 25 parts Fresh water 1000 parts Formalin. (5 per cent.) Formalin (or forraol) 50 parts Water 950 parts It is suggested that a vessel should carry for every 100 passengers : bichloride of mercury, 5 pounds; carbolic acid, 10 pounds; alcohol, 10 pounds, and formalin, 10 pounds. EFFICIENCY OF FOREIGN REGULATIONS. The wisdom of this method of procedure and the efficient working of these regulations are demonstrated by the following statement taken from the report of the medical officer of the Marine-Hospital Service on duty at Naples, Italy, where, during the summer of 1893, cholera was epidemic: — "From the 15th of July to August 17th there were eight vessels cleared from Naples with steerage passengers — four for New York and FOREIGN QUARANTINE. 487 four for South American ports. The first to leave was the Karamania, for ISTew York, on July 15th. No cholera at that time existed in Naples. The first case occurred in Naples on the night of the 16th, and the result of the bacteriological examination was not known until the afternoon of the 17th or morning of the 18th. "The passengers for the Karamania and the ship itself were put through the established routine. The ship was cleaned; ventilation, etc., altered to conform with the United States law; closets and hos- pitals put in good order; water- and food- supply attended to; pas- sengers inspected and vaccinated, and both their baggage and clothing searched for food. Three days after sailing, i.e., on the 18th, a death from cholera occurred, and just before reaching New York there were two more. It is not unlikely that the infection in the first cases was traceable to the same source as those occurring in Naples on the 16th. It is more than probable that but for the careful exclusion of food brought by passengers there would have been more cases on the re- maining three ships for the United States. The regulations govern- ing infected ports were rigidly enforced. The first vessel to leave, four days after the cholera was announced, was the Massilia. Her passen- gers were met at the trains and conducted immediately on board; were there isolated three days, and all their baggage transferred across city unopened. All food was carefully looked into; all from persons or baggage excluded; and the baggage of a few, about whose ante- cedents there was doubt, disinfected by steam. The ship was warped out some distance from the pier every night, and an inspector kept on board night and day. There being no cholera known to exist anywhere in Italy outside of Naples, it was not thought necessary to disinfect all baggage or isolate for five days. She arrived safely in New York without mishap. The remaining two for the United States were the Weser and Cashmire; in both cases the regulations were enforced in detail. One lay about a mile and a half otf shore during her five days. The other cruised at sea. In both cases an inspector was kept aboard day and night. Both escaped cholera. "The four for South America, with the result in each case, were as follows : The figures are not official, l)ut are practically accurate in every respect. All were turned back by the South American author- ities: Vencinzio Florio — about 50 deaths; Andrea Dorio — 90 on way out, total not ascertained; El Remo — 84 deaths; Carlo R. — about 230 deaths. "To summarize, then, eight ships left Naples. The water-supply was the same and the food nbont the same; tlie class of passengers TEXT-BOOK OF HYGIENE. identical, and their places of origin similar — in many cases identical. All four leaving without precautions became floating pest-houses. Of the four for the United States the one leaving before cholera appeared in Naples had three deaths; the other three were made to conform to the regulations, and all escaped. In other words, every ship that left Naples had cholera except those in whose case the 'infected port' regulations were carried out; and of the five that had cholera, the only one that escaped with less than 50 deaths was the one on which our 'non-infected port' regulations were enforced, she having only 3 deaths en route. In addition, the enforcement of the regulations compelled the abandonment of a number of other sailings for the United States. The escape of the Massilia, Cashmire, and Weser may be 'post,^ not 'proper hoc,' but we certainly have the right to consider the evidence to be strongly on the side of 'propter.' " DOMESTIC QUARANTINE. The trans-oceanic part of the voyage completed, the vessel ar- rives in the waters of the United States, and here she is confronted by a municipal. State, or national quarantine station, where the ques- tion will be determined whether the measures prescribed have been carried out, whether they have been effective in the particular case, and, in fine, whether the vessel, her crew, passengers, and cargo, are or are not a menace to the health of the city and the country at large. MARITIME QUARANTINE STATIONS. In describing a maritime quarantine station it should be borne in mind that the details in the plant must vary in accordance with the special demands of each port. Thus, it is not to be expected that at Charleston, where immigra- tion is limited, there should be the same provisions for detention of immigrants as at New York, through whose portals more than one- third of a million of immigrants pass each year; or San Francisco, where enter the throng of travelers and immigrants from the far East. We should not expect that Boston, in the more salubrious North, would have the means or adopt the practice of discharging ballast, cleaning and fumigating every vessel from an infected port, which is the invariable custom at Pensacola. But, leaving these variations for subsequent notice, the first thing to be considered, in the establishment of a complete mari- time quarantine, is proper location. This must be at a point remote DOMESTIC QUARANTINE. 489 from city or village boundaries, and not likely to be encroached upon by urban growth. It should be more or less removed from the chan- nels of commerce, and yet be easily accessible. Indifference to proper location could very readily make the quarantine station a source of danger instead of a protection. THE QUARANTINE PLANT. The requirements of a maritime quarantine station may be enu- merated as follows: 1. A boarding-station. 2. A boarding-vessel. 3. Anchorages. 4. Wharves with warehouse, disinfecting machinery, and machinery for discharge of ballast. 5. Lazaretto, or hospital for treatment of contagious diseases. 6. Hospital for treatment of non- contagious diseases. 7. Barracks for the detention, in groups, of sus- pects, or persons who have been exposed to contagion or infection. 8. Bath-house. 9. Water-supply. 10. A cremation furnace. 11. Quarters for medical officers. 12. Laundry. 1. The Boarding-station. — This includes a boat-house, with boat- men's quarters so located as to avoid infection from the Lazaretto, and to be within easy reach of passing commerce. 2. Boarding-vessel. — The facilities for boarding and inspection will vary with the location of the station, whether within the limits of a land-locked harbor or exposed to the full force of wind and sea. In the former case a steam- or naphtha- launch, or even a row-boat, will suffice; but in the latter case the boarding-boat must be a steamer, preferably of the sea-going tug-boat type, for it must be remembered that any delay in making the inspection inflicts hard- ship on commerce, and must inevitably produce discontent and complaint. 3. Anchorages. — Two anchorages, one for infected and one for non-infected vessels. The anchorage for the detention of the infected vessel should be conveniently removed from the main establishment and safely remote from the track of commerce. Its position should be sheltered, and good holding-ground for vessels' anchors is of the first importance. The channel to the anchorages, and, if necessary, their boundaries, should be plainly marked by buoys. 4. Wharves. — A wharf or pier is a prime essential in the equip- ment of a complete station, and should be located in water at least twenty feet deep, and should be of such length that the largest ves- sels trading at the port can lie there safely; at least, in all ordin- ary weather. Upon this wharf there should be a warehouse for the Btorage of baggage and portions of cargo (practically, cargo is never 490 TEXT-BOOK OF HYGIENE. fully discharged, being disinfected in situ). On the wharf should be placed the steam disinfecting chambers, sulphur-furnaces, and tanks for holding disinfecting solutions. (At certain stations the disinfect- ing apparatus is necessarily placed on a barge.) When required, a special, additional wharf should be provided for the discharge of ballast. Steam Disinfecting' Chambers. — The principle of disinfection by steam was first advocated by Dr. A. N. Bell, of Brooklyn; but tho credit of first designing apparatus for the special purpose belongs to Dr. Joseph Holt, and his design was subsequently improved upon by Dr. Wilkinson and others. Steam Chambers. — These chambers consisted of cylindrical shells, made of strong boiler-iron, 40 to 50 feet long and 7 to 8 feet in diameter (inside measurement), furnished with doors at each end. The steam was admitted directly to the interior of the chamber, and in addition there was a coil of pipe for the application of dry heat. These chambers were fairly efficient in action, but there was a great waste of space, and with the exercise of every possible care there was always more or less wetting of fabrics by the water of condensation. Many improvements have been made from time to time in the con- struction of steam disinfecting chambers, those constructed for the national quarantine station at San Francisco, Cal., being of the same general construction, but dispensing with the coil of pipe, and substi- tuting therefor a jacket surrounding the entire chamber. The most recent steam chambers are of rectangular section, 16 feet in length, 4 feet 6 inches in width, and 5 feet 6 inches in height, and are provided with steam-tight doors opening at either end. The chambers are constructed of an inner and outer steel shell 2i/2 inches apart, with cast-iron end frames, intermediate truss bands, and of stay- bolt construction. The doors have concave steel plates riveted to cast angle frames fitted with heavy rubber gaskets; they are handled by convenient cranes, and drawn tight by drop-forged steel eye-bolts, swinging in and out of slots in the door-frames. The rectangular form is adopted in preference to the round, as it gives the most effective space during exposure, with little loss of steam, and enables cars on tracks to be readily handled in and out. The jacket is used to give perfect circula- tion and distribution of heat, to prevent condensation, and to dry the goods exposed. The jackets, which are filled with steam during the entire operation of the plant, make the chambers drying ovens; so that tlie articles to be disinfected are brought to the required tempera- DOMESTIC QUARANTINE. 491 ture before the admission of steam to the inner chamber, and are thoroughly dried after the steam has been exhausted. In the experiments of Professor Koch in connection with Dr. Wollfhiigel it was found that hot air alone, even at a temperature of 230° to 248° F., after an exposure of three hours, would not with certainty destroy bacilli and spores. It is necessary, therefore, to eliminate the possibility of the pocketing of air, or of a mixture of air and steam, during exposure. To prevent this an inspirator is attached to the system of piping, whereby a vacuum of 10 to 15 inches is pro- duced in the chamber prior to the admission of steam. In previous chambers this important point was neglected, and this accounts for the unreliable results obtained by a number of disinfecting plants. For convenience of handling the goods to be disinfected, each chamber is provided with two cars of light wrought-iron construction, with removable trays with bottoms of galvanized-iron wire- netting, and having a series of bronze wardrobe-hooks in the top of the frame- work, thus permitting the articles to be laid out upon the trays, or in the case of finer clothing, to be hung upon the hooks. The doors at both ends allow the cars to be brought in at one end and removed at the other, thus securing complete separation of infected and disin- fected articles. After exposure the cars, upon being unloaded, are returned to the working end of the chamber by means of transfer tables and side-tracks, permitting a continuous working of the plant. The system of piping is so arranged that steam may be admitted to the top or bottom of the chamber at will, through several openings, and has perfect circulation. Galvanized-iron hoods are placed in the chambers, so that steam is not forced directly on the clothing. The chamber is provided with thermometers to register the temperature, vacuum and steam-gauges, safety-valves, traps, and is covered with magnesia non-conducting covering. Sulphur-furnace. — For a long time the method of sulphur fumi- gation pursued was to put into iron pots a quantity of sulphur vary- ing from three to four pounds to one thousand cubic feet, igniting this by means of alcohol, and to place them in the hold or apartment to be disinfected. An apparatus has been designed for the purpose of producing SOg in greater percentage, and consists of a furnace built on the reverberatory plan, with a series of shelves arranged one above another, each shelf carrying a pan of burning sulphur. A forced draught is kept up by means of a fan-blower connected at the bottom. The draught of air charged from the burning sulphur is made to reach and pass over the shelP above by means of apertures made by 492 TEXT-BOOK OF HYGIENE. shortening the shelves alternately at their rear and front extremities. With an experimental furnace, Dr. Kinyoun states that "repeated experiments gave from 14 to 16 per cent, of SO2, temperature 31° C, while burning sulphur in a closed place gave only 6 per cent, at 21° C. — i.e., the air would not support the combustion of sulphur above that percentage." This has been almost entirely superseded by a furnace that is simpler in construction, and which has given admirable results in practice. The furnace is double, and has been provided with small fire-boxes at each end, over which are placed two shallow cast-iron pans five feet long, and the whole inclosed in a frame of sheet-iron. The sulphur is placed in the pans and a fire lighted in the furnaces, melting the sulphur, which quickly ignites. To prevent too rapid combustion baffle plates are arranged, and the proper quantity of air is admitted through adjustable valves in the furnace-fronts. The fumes of sulphur dioxide thus generated are collected and carried into a reservoir, from which they are sucked by an exhaust fan, and are thence forced through piping and large flexible hose to the apartment to be fumigated. The sulphur-furnace in use at the Louisiana Quarantine Station is the same in general principle, with the addition that the air sup- plied to the burning sulphur is aspirated from the hold of the vessel, and then forced into the furnace. Disinfeciion hy Germicidal Solutions. — The apparatus for the use of the disinfecting solutions consist of a tank or tanks elevated above the level of the floor of the wharf to a sufficient height to force the solution through a hose and nozzle to the parts of the ship to be reached. The tank is to be filled by a steam-pump, and the solution is easily made by surmounting the tank with a keg perforated by numerous holes, in which keg the powdered bichloride is to be put, and the water for filling the tank pumped over it. It is a much better plan to have the bichloride solution distrib- uted by means of a special pump (made of iron to prevent amalgama- tion), as, with the pressure of the pump behind it, it penetrates much more deeply into cracks and crevices and, in fact, knocks the dirt and filth out of them. 5 and 6. Hospitals. — The propriety of having separate hospitals for contagious and non-contagious diseases is so obvious that it need not be dwelt on here, and the necessity of a separate establishment for suspects, until the nature of their complaint can be positively DOMESTIC QUARANTINE. 498 made out, is patent and only in accord with expediency and the ordi- nary instincts of humanity. 7. Barracks. — Barracks for the detention of suspects are not an essential part of the equipment of every quarantine station, but are a necessity only at such stations as are situated at the great ports of entry, which are the ports of arrival of the vast hordes of immi- grants who seek our shores. Barracks are an indispensable adjunct in the management of ship-loads of immigrants suspected of being infected with cholera, typhus fever, and small-pox, and would be required in the case of yellow fever but for the fact that there is little or no immigration from the yellow-fever zone. The barracks should be commodious, substantial, and yet of sim- ple and inexpensive construction. They should be well ventilated and so arranged that every part of the building is under constant surveillance, and so subdivided that the inmates are divided into small groups and intercourse between the groups prevented. The immigration laws require that the immigrants shall be listed and ar- ranged in groups of thirty, and it would be well that this number be preserved as the unit for segregation. The barracks should be fur- nished with bunks, arranged in tiers one above the other, and fur- nished with bedding of a simple and inexpensive character. Clothing of a simple but sufficient kind, and capable of easy laundering, should be provided in sufficient quantity to furnish each inmate of the barracks with a change while his or her own personal effects are undergoing the process of disinfection. Attached to the barracks there should be a kitchen, thoroughly equipped with all the facilities for furnishing hot food of a simple character for the num- ber of inmates provided for by the barracks. Dining-rooms should be arranged, and special care should be taken to prevent the carrying of any food into the barracks. It is perhaps needless to say that, in the barracks, the sexes should be separated, and the better arrange- ment is to have two buildings — one for men and one for women and children. Latrines. — Latrines of ample size should be provided, and should be so arranged that all dejecta may be received into metallic vessels containing a germicidal solution of acknowledged potency; or, if the dejecta are to be received into a sewer, there should be some provision made for their complete disinfection prior to their discharge into the sea or a cess-pool. 8. Bath-house. — Bathing facilities are an important part of the equipment of a quarantine station designed for the handling of large 494 TEXT-BOOK OF HYGIENE. numbers of suspects. The best form of bath for the purpose is the shower- or rain-bath, it being more easily managed, more expeditious, and probably more efficacious than the tub-bath. The bath-house should be provided with a room for disrobing, from which the sus- pects will pass into the bathing-stalls proper, and there receive a bath the temperature of which is under the sole control of the bath- attendant. From the bath the suspect will pass into a robing-room, where he will be given a suit of sterile clothing, while the clothing which was removed in the disrobing-room is carried by proper attend- ants to the disinfecting apparatus, there to be rendered safe by ster- ilization. 9. Water-supply. — An abundant supply of pure water is not only a desideratum, but a prime necessity, at all quarantine stations where it is designed to accommodate cholera suspects. It would be desir- able to provide a supply of twenty gallons per capita per day, and no arrangement will probably give such good results as the sinking of an artesian well, if the nature of the soil and the geological formation permit. If it is impracticable to sink such a well, the next best plan would be to arrange for the distillation or sterilization, by boiling, of a sufficient quantity of water for drinking purposes. 10. Crematory. — A crematory is a desirable part of the equip- ment of every quarantine station, as it admits of no argument that cremation is the best possible method of disposing of the bodies of those dead of contagious or infectious disease. In addition, it would be desirable that all garbage and waste about a quarantine station be incinerated to prevent the possibility of infection, 11 and 12. — Detailed description of quarters for medical officers and of laundry is unnecessary. Having thus considered the necessities and the desiderata in the equipment of a quarantine station, it is now proper to consider the regulations governing them, and for this purpose are here ap- pended the regulations prepared by the Supervising Surgeon-General of the Marine-Hospital Service, and promulgated by the Secretary of the Treasury on April 26, 1894. These regulations are to be con- sidered a minimum for the stations under municipal and State con- trol, some of which have additional requirements: — DOMESTIC QUARANTINE. 495 Domestic Regulations. QUABAJSTTINE REGULATIONS TO BE OBSERVED AT PORTS AND ON THE FRON- TIERS OF THE United States and its Possessions and Dependencies. Preamble. 52. At or convenient to the principal ports, quarantine stations should be equipped with all appliances for the inspection and treat- ment of vessels, their passengers, crews, and cargoes. 53. For ail ports where such provisions have not been made, in- spection stations should be maintained. An inspection service should be maintained for every port throughout the year. 54. At a fully equipped quarantine station there should be ade- quate provision for boarding and inspection, apparatus for mechan- ical cleansing of vessels, apparatus for disinfection by steam, by sul- phur, by formaldehyde, by disinfecting solutions, or any other method prescribed in these regulations; also a clinical laboratory, hospitals for contagious and doubtful cases, a steam laundry, detention bar- racks for suspects, bathing facilities, a crematory, a sufficient supply of good water, and a proper system for the disposal of sewage. 55. The personnel of quarantine stations in the yellow-fever zone and on fruiters and other vessels of regular lines bound for southern ports from ports where yellow fever prevails should be immune to yellow fever. 56. At quarantine stations all articles liable to convey infection should be handled only by the employees of said station unless the services of the crew of the vessel in quarantine are indispensable. 57. Vessels having been treated at national quarantine stations that are located a considerable distance from the ports of entry of said vessels may be inspected by the local quarantine officer, and if for any sanitary reason it is considered inadvisable to admit the vessel, he should report the facts immediately by telegraph, when possible, to the Surgeon-General of the Public Health and Marine-Hospital Serv- ice, detaining the vessel pending his action.. 58. The following regulations are the required minimum stand- ard and do not prevent the addition of such other rules as, for special reasons, may be legally made by State or local authorities. Inspection. 59. Every vessel siil>ject to quarantine inspection, entering a port of the United States, its possessions or dependencies, shall be 496 TEXT-BOOK OF HYGIENE. considered in quarantine until given free pratique. Such vessel shall fly a 3'ellow flag at the foremast head from sunrise to sunset, and shall observe all the other requirements of vessels actuall}^ quarantined. 60. Vessels arriving at ports of the United States under the following conditions shall be inspected by a quarantine officer prior to entry: — (a) All vessels from foreign ports except those enumerated in paragraph 4. (b) Any vessel with sickness on board. (c) Vessels from domestic ports where cholera, plague, or yel- low fever prevails, or where small-pox or typhus fever prevails in epidemic form. (d) Vessels from ports suspected of infection with yellow fever, having entered a port north of the southern boundary of Maryland without disinfection, shall be subjected to a second inspection before entering any ports south of said latitude during the quarantine season of such port. 61. The inspections of vessels required by these regulations shall be made between sunrise and simset, except in case of vessels in dis- tress. 62. In making the inspection of a vessel, the bill of health and clinical record of all cases treated during the voyage, crew and pas- sengers' lists and manifests, and when necessary, the ship's log shall be examined. The crew and passengers shall be mustered and exam- ined and compared with the lists and manifests and any discrepancies investigated. The clinical thermometer should be used in the exam- ination of the personnel of vessels under suspicion. When a freight manifest shows that rags and other articles requiring disinfection under these regulations are carried by the vessel, a certificate of dis- infection, signed by a United States consul or a medical officer of the United States, shall be exhibited and compared with same. If no certificate of disinfection is produced the collector of customs at the port of entry shall be notified of same by the quarantine officer. The collector of customs shall then hold such consignment in a designated place separate from other freight pending the arrival of the certificate of disinfection; and in the event of its nonarrival, the articles shall be disinfected as hereinbefore prescribed, or shall be returned by the common carrier conveying the same. 63. The medical officers of the United States, duly clothed with authority to act as quarantine officers at any port or place within the United States, and when performing the said duties, are hereby au- DOMESTIC QUARANTINE. 497 thorized to take declarations and administer oaths in matters per- taining to the administration of the quarantine laws and regulations of the United States. (Act of March 2, 1901, sec. 12.) 64. No person, except the quarantine officer, his employees, United States customs officers, pilots, or other persons authorized by the quarantine officer, shall be permitted to board any vessel subject to quarantine inspection until after the vessel has been inspected by the quarantine officer and granted free pratique, and all such persons so boarding such vessel shall, in the discretion of the quarantine offi- cer, be subject to the sanie restrictions as the personnel of the vessel. 65. Towboats or any other vessels having had communication Avith vessels subject to inspection shall themselves be subject to in- spection. 66. After arrival at a quarantine station of a vessel carrying immigrants and upon which there has appeared during the last voy- age a case of cholera, small-pox, typhus fever, or plague, and after quarantine measures provided by regulations of the Treasury Depart- ment have been enforced and the vessel given free pratique, it is hereby ordered that notification of the above-mentioned facts be trans- mitted by the quarantine officer to the Commissioner of Immigration at the port of arrival, who shall be requested to transmit, by mail or telegraph, to the State health authorities of the several States to which immigrants from said vessel are destined, the date of departure, route, number of immigrants, and the point of destination in the respective States of the immigrants from said vessel, together with the statement that said immigrants are from a vessel which has been subject to quarantine by reason of infectious disease, naming the dis- ease. This information is furnished to State health officers for the purpose of enabling them to maintain such surveillance over the arriving immigrants as they may deem necessary. 67. When a vessel arriving at quarantine has on board any of the communicable but non-quarantinable diseases, the quarantine officer shall promptly inform the local health authorities of the existence of such disease aboard and shall make every effort to furnish such notifi- cation in ample time, if possible, to permit of the case being seen by the local authorities before discharge from the vessel. Quarantine. 68. Vessels arriving under the following conditions shall be placed in quarantine: — 498 TEXT-BOOK OF HYGIENE. (a) With quarantinable disease on board or having had such disease on board during the voyage. (b) Any vessel which the quarantine officer considers infected. (c) If arriving at a port south of the southern boundary of Maryland in the season of close quarantine, May 1 to November 1, directly or via a northern port, from a tropical American port, unless said port is known to be free from yellow fever. (d) In the case of vessels arriving at a northern port without sickness on board from ports where yellow fever prevails, the per- sonnel shall be detained under observation at quarantine to complete five days from the port of departure. (e) Towboats and other vessels having had communication with vessels subject to quarantine shall themselves be quarantined if they have been exposed to infection. 69. Vessels arriving under the following conditions need not be subject to quarantine: — A. Vessels from yellow fever ports bound for ports in the United States north of the southern boundary of Maryland, with good sani- tary condition and history, having had no sickness on board at ports of departure, enroute, or on arrival, provided they have been five days from last infected or suspected port. B. Vessels engaged in the fruit trade may he admitted to entry without detention, provided that they have complied in all respects with the special rules and regulations made by the Secretary of the Treasury with regard to vessels engaged in said trade. General Requirements at Quarantine. 70. Pilots will be detained in quarantine a sufficient time to cover the period of incubation of the disease for which the vessel is quarantined, if, in the opinion of the quarantine officer, such pilots have been exposed to infection. The dunnage of pilots shall be dis- infected when necessary. 71. No direct communication shall be allowed between any vcFsel in quarantine and any person or place outside, and no communication whatever between quarantine or any vessel in quaratine and any person or place outside except under the supervision of the quaran- tine officer. 72. Street cleanings, street sweepings, or any other form of bal- last containing organic refuse must be discharged at the quarantine station. DOMESTIC QUARANTINE. 499 73. No presumably infected ballast shall be allowed to leave the quarantine station until disinfected. 74. After a vessel has been rendered free from infection, it may be furnished vi^ith a fresh crew and released from quarantine, while all or part of the personnel are detained. Under these circumstances the quarantine officer must exercise the greatest care that the vessel shall not become reinfected, especially by contact with persons in quarantine or infected objects. 75. Vessels detained at any national quarantine will be subject to such additional rules and regulations as may be promulgated from time to time by the Surgeon-General. 76. The form of certificate which shall be issued to a vessel by the health officer when he releases her from quarantine shall be pre- scribed by the Surgeon-General of the Public Health and Marine- Hospital Service, and shall embody the statement that the vessel has in all respects complied with the quarantine regulations prescribed by the Secretary of the Treasury, and that in the opinion of the quarantine officer she will not convey quarantinable disease, and that said vessel is granted free pratique to enter her port of destination, the name of which is to be embodied in the blank. 77. The persons detained shall be inspected by the physician twice daily, and be under his constant surveillance, and no intercourse will be allowed between different groups while in quarantine. 78. No articles from an infected vessel shall be carried into the place of detention until disinfected. 79. Cleanliness of quarters and of person shall be enjoined and daily enforced. Disinfection shall be practiced where there is any possibility of infection. 80. The water and food supply shall be strictly guarded to pre- vent any contamination. 81. Water-closets, urinals, privies, or troughs shall be provided, and their contents disinfected before they are discharged. 83. In any group in which communicable disease appears, the sick will be immediately isolated in hospital, and the remaining per- sons in the group and their effects appropriately treated and then removed to other quarters if possible, and the compartments disin- fected. 83, Communication between the physician and attendants of the hospital and those detained in other parts of the quarantine station shall be reduced to a minimum. 84. No convalescent shall be discharged from quarantine until 500 TEXT-BOOK OF HYGIENE. after a sufficient time has elapsed to insure his freedom from infec- tion, and this is to be determined by bacteriological examination where possible. 85. No other person shall be discharged from quarantine until the period of incubation of the disease has elapsed since the last exposure to infection. 86. The body of no person dead of quarantinable disease shall be allowed to pass through quarantine until one year has elapsed since death. Such bodies must l)e transported in hermetically sealed cof- fins, the outsides of which have been carefully disinfected. In the case of the bodies of such persons as may have died on the voyage or upon arrival at quarantine, cremation should be re- sorted to if practicable and consented to ; if not, the body should be wrapped without preliminary washing in a sheet saturated with a solu- tion of bichloride of mercury 1 :500 and buried, surrounded by caustic lime. 87. The quarantine officer shall report to the Secretary of the Treasury all violations of the quarantine laws. He should also report the facts in the case to the Surgeon-General of the Public Health and Marine-Hospital Service. 88. The quarantine officer shall report to the collector of cus- toms any vessel which arrives without the bill of health hereinbefore prescribed. 89. All vessels requiring inspection under these regulations must present to the collector of customs at the port of entry the quaran- tine certificate above prescribed. Special Regulations on Account of Cholera. 90. For the purpose of these regulations five days shall be con- sidered as the period of incubation of cholera. 91. If the vessel carry persons from cholera-infected ports or places, a bacteriological examination should be made of any cases of diarrhea to exclude cholera before granting free pratique. 92. If cholera has appeared on board, remove all passengers from the vessel and all of the crew, save those necessary to care for her; place the sick in hospital. Carefully isolate those especially suspected and segregate the remainder in small groups. ISTo communication should be held between these groups. Those believed to be especially capable of conveying infection must not enter the place of detention until they are bathed and furnished with non-infected clothing; nor DOMESTIC QUARANTINE. 501 shall any material capable of conveying infection be taken into the place of detention, especially food and water. 93. Water and food supply must be strictly guarded to prevent contamination and issued to each group separately. 94. Food of a simple character, sufficient in quantity, thoroughly cooked, shall be issued to those detained in quarantine. No fruit or uncooked vegetables shall be permitted. 95. The greatest care must be exercised to prevent the spread of the infection through the agency of flies or other insects. 96. The dejecta from all persons in quarantine on account of cholera shall be disinfected before final disposition. 97. The water supply of the vessel, if suspected of infection, must be disinfected and then changed without delay; the casks or tanks disinfected and after thorough rinsing refilled from a source of un- doubted purity, or the water furnished must have been recently boiled. 98. The baggage or effects of passengers and crew that may have been exposed to infection must be disinfected. 99. Articles of cargo which have been exposed to infection and are liable to convey the same must be disinfected. 100. Living apartments and their contents and such other por- tions of the vessel as have been exposed to infection must be dis- infected. 101. Water ballast taken on at a cholera-infected port should be discharged at sea, or if discharged in fresh or brackish water must previously be disinfected. Vessels arriving with water ballast pre- sumably infected must return to sea under guard in order to dis- charge such ballast. If practicable the tanks should be disinfected before being flushed, and refilled with sea water. Special Regulations on Account of Yelloiv Fever. 102. For the purpose of these regulations, five days shall be con- sidered as the period of incubation of yellow fever. 103. Where practicable remove the sick to hospital; remove and isolate all persons not required for care of vessel. 104. For the destruction of mosquitoes there shall be a prelimi- nary and simuHaneous fumigation of all parts of the vessel by sul- phur dioxide gas. In cal)ins containing articles liable to damage by sulphur dioxide, pyrethrum powder may be burned instead. 105. If, from the disposition of the cargo or any other reason, the previous fumigation is deemed not to have been effective, a com- 502 TEXT-BOOK OF HYGIENE. plete fumigation is now to be done^ simultaneously, of the whole vessel. Measures are in all cases to be taken to destroy larvge of mos- quitoes aboard. 106. The personnel of the vessel shall be detained five days from completion of disinfection, or if they have been removed before dis- infection of the vessel, their detention shall begin from last possible exposure to infection. If cases of yellow fever have occurred aboard, the time of deten- tion at stations south of the southern boundary of Maryland must be jextended to six days.- 107. If the vessel has in all respects complied with the quaran- tine regulations to be observed at foreign ports in such cases, and has been disinfected under the supervision of an accredited medical officer of the United States at the port of departure, she may, upon arrival at her port of destination in the United States, with good sanitary history and in good condition, be subject to the following treat- ment : — (a) If arriving in five days or less, she may be admitted to pratique without disinfection or further detention than is necessary to complete the five days. (&) If arriving after five days and within ten days, she may be immediately fumigated and admitted without detention. (c) If arriving after a longer voyage than ten days, she shall be treated as if she had not been subjected to any previous treatment.''^ 108. Passenger traffic without detention may be allowed during the close quarantine season, May 1 to November 1, from ports in- fected with yellow fever to ports in the United States south of the southern boundary of Maryland under the following conditions : — (a) Vessels to be of iron or the best class of wooden vessels, and to be cleaned immediately prior to taking on passengers. The officer issuing the bill of health to these vessels shall withhold the same if the vessel is not in first-class sanitary condition and complying in every respect with- the conditions stated in this paragraph. (6) The vessel must lie at approved moorings in the open har- bor; must not approach the wharves, nor must the crew be allowed ashore at the port of departure. Every possible precaution must be - The period of incubation of yellow fever is not rarely over five days. ' If the vessel should have been in transit for a considerable number of days, it is obvious that a case of yellow fever may have occurred and re- covered, leaving the vessel infected, and not affording any opportunity to the quarantine officer to determine same. DOMESTIC QUAllANTINE. 503 taken to prevent the ingress of mosquitoes, and to provide for the destruction of these should they find ingress. (c) All passengers and crew must be immune to yellow fever and so certified by the United States medical officer.* 109. The disinfection of baggage for yellow fever is not required, but baggage destined directly or indirectly for any State shall be dis- . infected at the request of the health officer of said State. All bag- gage shall be inspected and the absence of mosquitoes definitely proven. The presence of any mosquitoes, regarding the infection of which the quarantine officer has doubts, shall be sufficient grounds for such further measures as the quarantine officer may deem Justi- fiable. Special Regulations on Account of Small-pox. 110. For the purpose of these regulations, fourteen days shall be considered as the period of incubation of small-pox. 111. On all vessels arriving with small-pox on board, or having had small-pox on board during the voyage, any of the personnel who have been exposed to the infection of the disease must be vaccinated or detained in quarantine not less than fourteen days, unless they show satisfactory evidence of recent successful vaccination or of hav- ing had small-pox. 112. Vessels arriving with small-pox on board which has been properly isolated and other sufficient precautions taken to prevent the spread of the disease need not be quarantined further than the re- moval of the sick, the disinfection of all compartments, baggage, and objects that have been exposed to the liability of infection, and such vaccination of the personnel as required in paragraph 111. 113. On vessels arriving with small-pox on board and where the proper isolation and other precautions have not been taken, all those whom the quarantine officer believes to have been exposed to the infection will be detained unless they have had small-pox or unless they show satisfactory signs of having been properly vaccinated within one year. 114. Living compartments and their contents or any other part of the vessel exposed to the infection must be disinfected. 115. The baggage and effects of passengers and crew that have been exposed to the infection must be disinfected. ^The pvidfinco of immunity which may be acoepted by the sanitary inspector is: First, proof of previous attack of yellow fever; second, proof of continued residence in an endemic focus of yellow fever for ten years. 504 TEXT-BOOK OF HYGIENE. Special Regulations on Account of Typhus Fever. 116. For the purpose of these regulations twelve days shall be considered as the period of incubation of tjqohus fever. 117. Vessels in otherwise good sanitary condition, but having typhus fever on board which has been properly isolated, need not be quarantined further than the removal of the sick, and disinfection of the compartments and their contents exposed to infection. 118. If the case has not been isolated, or the disease has spread on board from person to person, the vessel will be quarantined, the sick removed, and those who have been exposed to the infection detained under observation. 119. Vessels in bad sanitary condition, on which the disease has appeared, will be quarantined until thoroughly cleansed and disin- fected throughout ; the sick will be cared for at isolated hospitals, and those exposed to the infection detained under observation. 120. The baggage and effects of passengers and crew that have been exposed to the infection must be disinfected. 121. Living compartments and their contents, or any other parts of the vessel exposed to the infection, must be disinfected. Special Regulations on Account of Leprosy. 122. Vessels arriving at quarantine with leprosy on board shall not be granted pratique until the leper with his or her baggage has been removed from the vessel to the quarantine station. 123. No alien leper shall be landed. 124. If the leper is an alien passenger and the vessel is from a foreign port, action will be taken as provided by the immigration law's and regulations of the United States. And to this end the case shall be certified as a leper and reported to the nearest commissioner of immigration. 125. If the leper is an alien and a member of the crew and the vessel is from a foreign port, said leper shall be detained at the quar- antine at the vessel's expense until taken aboard by the same vessel when outward bound. Such case of leprosy should be promptly re- ported to the collector of customs at the port of arrival of the vessel, and the collector shall exact a bond from the vessel for the reship- ment of the said alien leper upon the departure of the vessel. DOMESTIC QUARANTINE. 505 Special Regulations on Account of Plague. 126, For the purpose of these regulations seven days shall be con- sidered as the period of incubation of plague. 137. In those actually exposed to the infection of plague the administration of antipest serum is regarded as a valuable prophyl- actic measure; for the prevention of the introduction of plague into a community liable to the introduction of plague through commercial intercourse, immunization by Haffkine's prophylactic is to be rec- ommended. 128. Vessels infected with plague, or suspected of such infec- tion, should be anchored at a sufficient distance from the shore or other vessels, to prevent the escape of rats by swimming. 129. In inspecting vessels from plague-infected ports, or vessels with plague on board at port of departure, en route or on arrival, the personnel of the vessel should be examined with special reference to the glandular regions, cervical, axillary, and inguinal, and for such examination as much clothing should be removed as may interfere with the thoroughness of the process. When possible, females should be examined by female inspectors.^ 130. In the inspection of vessels for plague, special attention must be directed to the discovery of cases of a mild type or of the pneumonic form of the disease. Suspected or doubtful cases should be subjected to bacteriological examination before the vessel is released. 131. On all plague-infected vessels, any of the personnel of such vessels who, in the opinion of the quarantine officer, are infected or have been exposed to infection, shall be bathed and body clothing and hand baggage disinfected. 132. Nothing shall be thrown overboard from the vessel, not even deck sweepings. Such material shall be burned in the furnaces of a steamer, or in a place specially designated, but not in the galley. 133. Special precautions must be taken against rats, mice, ants, flies, fleas, and other animals, on account of the danger of the infec- tion of the disease being spread through their agency. 134. As soon as practicable, there shall be a preliminary disin- fection with sulphur dioxide for the purpose of killing rats and ver- min, before further disinfecting processes are applied to the vessel and her cargo. The killing of any escaping rats shall be provided ''T'he examination herein provided being an exceedingly delicate matter, the greatest possible care is to be used by the quarantine officer to avoid any grounds for complaint of indecent exposure, and more particularly vi^ith regard to females. 506 TEXT-BOOK OF HYGIENE. for by a water guard in small boats, and no person with abrasions or open sores should be employed in the handling of the vessel or her cargo. 135. The vessel shall be submitted to a simultaneous disinfection in all parts with sulphur dioxide to insure the destruction of rats and vermin. The rats shall be subsequently gathered and burned, due precautions being taken not to touch them with the bare hands, and the places where found disinfected with a germicidal solution; and the quarantine officer shall assure himself that the vessel is free of rats and vermin before granting free pratique. 136. Disinfection of vessels for plague shall be as follows: — With cargo : After twelve hours' exposure to sulphur dioxide, the upper 4 to 6 foot layer of cargo may be removed and placed on lighters exposed to the sun. This process of disinfection by night, and removal of successive layers of cargo by day, to be continued until hold is empty. 137. Vessels without cargo shall be disinfected by sulphur diox- ide, followed by germicidal solutions, in accordance with the general regulations for disinfection, paragraphs 156 to 185. Canadian and Mexican Frontier's. 138. When practicable, alien immigrants arriving at Canadian or Mexican ports, destined for the United States, shall be inspected at the Canadian or Mexican port of arrival by the United States consular or medical officer, and be subjected to the same sanitary restrictions as are called for by the rules and regulations governing United States ports. 139. Inspection cards will be issued by the consular or United States medical officer at the Canadian or Mexican port of arrival to all such alien immigrants, and labels affixed to their baggage, as is required at foreign ports in the case of those coming direct to any port of the United States. 140. If any person be found suffering from a quarantinable dis- ease, or be presumably infected, he shall be denied entry or shall be kept under quarantine observation so long as danger of conveying the infection exists. 141. Any baggage or other effects believed to be infected shall be refused entry unless disinfected in accordance with these regula- tions. 142. Persons coming from localities where cholera is prevailing DOMESTIC QUARANTINE. 507 shall not be allowed entry until after five days have elapsed since last presumable exposure to infection, and their baggage disinfected. 143. During the quarantine season persons not positively identi- fied as immune to yellow fever, coming from places where yellow fever prevails, will not be permitted to enter until they have been away from said localities five full daj^s. 144. Persons coming from localities where small-pox is prevail- ing shall not be allowed entry without vaccination, unless they are protected by a previous attack of the disease or a recent successful vaccination. The baggage of persons from such localities shall be disinfected. 145. Persons coming from localities where typhus fever prevails in epidemic form shaU not be allowed entry until twelve days have elapsed since their last possible exposure to infection and the disin- fection of their baggage. 146. Persons coming from localities where plague is prevailing shall not be allowed entry until seven days have elapsed since their last possible exposure to infection and the disinfection of their bag- gage. 147. No common carrier which is infected, or suspected of being infected, shall be allowed to enter the United States until after such measures have been taken as will render it safe. 148. Articles of merchandise, personal effects, etc., which are presumably infected, shall not be allowed entry into the United States until after disinfection. 149. Eags gathered and baled in Canada, accompanied by affi- davits that the ports or places where collected or handled Avere free from quarantinable disease for thirty days prior to shipment, may be admitted to entry; but rags from foreign ports shipped through Can- ada shall not be admitted to entry unless they are accompanied by a certificate of a United States consul or medical officer of the United States that they have been disinfected, or until after they have been unbaled and disinfected at the port of arrival. 150. AYhere not otherwise specifically stated, the rules and regu- lations for maritime quarantine shall be applied at stations on the Canadian and Mexican frontiers; and the methods of disinfection shall be those prescribed in these regulations. SprcinI Rrf/iiJaiions Relating to Naval Vessels. 151. Vessels of Ihe U. S. Navy may be granted the hereinafter stated exemptions from quarantine regulations, but are subject to 508 TEXT-BOOK OF HYGIENE. quarantine inspection upon arrival at a port of the United States. 152. The certificates of the medical officers of the U. S. Navy as to the sanitary history and condition of the vessel and its personnel may be accepted for naval vessels by the quarantine officer boarding the vessel in lieu of an actual inspection. 153. Vessels of the U. S. Navy having entered the harbors of infected ports, but having held no communication which is liable to convey infection, may be exempted from the disinfection and deten- tion imposed on merchant vessels fom such ports. Inspection of State and Local Quarantine. 154. In the performance of the duties imposed upon him by the act of February 15, 1893, the Surgeon-General of the Public Health and Marine-Hospital Service shall, from time to time, personally or through a duly detailed officer of the Public Health and Marine- Hospital Service, inspect the maritime quarantines of the United States, State and local, as well as national, for the purpose of ascer- taining whether the quarantine regulations prescribed by the Secre- tary of the Treasury have been or are being complied with. The Surgeon-General, or the officer detailed by him as inspector, shall, at his discretion, visit any incoming vessel or any vessel detained in quarantine, and all portions of the quarantine establishment, for the above-named purpose, and with a view to certifying, if need be, that the regulations have been or are being enforced. 155. The Surgeon-General of the Public Health and Marine- Hospital Service is authorized, when in his discretion such action is necessary in the interest of the public health, to remand, by direction of the Secretary of the Treasury, any vessel to the nearest national. State, or local quarantine station provided with proper facilities for handling infected vessels. Disinfectants Authorized by these Eegulations and the Proper Methods of Generatincx and Using Same. Physical Disin.fectants. 156. Burning. Of unquestioned efficiency, but seldom required. 157. Boiling. Very efficient and of wide range of applicability. The articles must be wholly immersed for not less than thirty min- utes in water actually boiling (100° C). The addition of 1 per cent, of carbonate of soda renders the process applicable to polished steel, cutting instruments, or tools. DOMESTIC QUARANTINE. 509 158. Steam: — (a) Flowing steam (not under pressure). Flowing steam (not under pressure) when applied under suitable conditions is an efficient disinfecting agent. The exposure must be continued thirty minutes after the temperature has reached 100° C. (h) Steam under pressure without vacuum. Steam under pres- sure will sterilize, provided that the process is continued twenty min- utes after the pressure reaches 15 pounds per square inch. The air must be expelled from the apparatus at the beginning of the process. If impracticable to obtain the designated pressure, a longer exposure will accomplish the same result. (c) Steam under pressure with vacuum. Steam in a special apparatus with vacuum attachment is the best method of applying steam under pressure, the object of the vacuum apparatus being to expel the air and to promote the penetration of the steam. The process is to be continued for twenty minutes after the pressure reaches 10 pounds to the square inch. Gaseous Disinfectants. 159. Sulphur dioxide. Sulphur dioxide is efficient, but requires the presence of moisture. It is only a surface disinfectant, and is lacking in penetrating properties. An atmosphere containing 4.5 per cent, can be obtained by burning 5 pounds of sulphur per 1000 cubic feet of space. This amount would require the evaporation or volatilization of about 1 pint of water. Under these conditions the time of exposure should be not less than twenty-four hours for bac- terial infections. A shorter time will suffice for fumigation necessary to kill mosquitoes and other vermin. 160. The sulphur may be burned in shallow iron pots (Dutch ovens) containing not more than 30 pounds of sulphur for each pot, and the pots should stand in vessels of water. The sulphur pots should be elevated from the bottom of the compartment to be disin- fected in order to obtain the maximum possible percentage of com- bustion of sulphur. The sulphur should be in a state of fine division, and ignition is best accomplished by alcohol ; special care to be taken with this method to prevent damage to cargo of vessel by fire; or the sulphur may be burned in a special furnace, the sulphur dioxide being distributed by a power fan. This method is peculiarly appli- cable to cargo vessels. K;i. TJqiifficd sulphur dioxide may be used for disinfection in 510 TEXT-BOOK OF HYGIENE. place of sulphur dioxide generated as above, it being borne in mind that this process will require 3 pounds of the liquefied gas for each pound of sulphur as indicated in the above paragraphs. 163. Sulphur dioxide is especially applicable to the holds of vessels, or to freight cars and apartments that may be tightly closed and which do not contain objects injured b}^ the gas. Sulphur dioxide bleaches fabrics or material dyed with vegetable or aniline dyes. It destroys linen or cotton goods by rotting the fiber through the agency of the acids formed. It injures most metals. It is promptly destruc- tive to all forms of animal life. This property renders it a valuable agent for the extermination of rats, insects, and other vermin. Formaldehyde Gas. 1G3. Formaldehyde gas is effective if applied by one of the methods given below. Formaldehyde gas has the advantage as a disinfectant that it does not injure fabrics or most colors. It is not poisonous to the higher forms of animal life. It fails to kill vermin such as rats, mice, roaches, bedbugs, etc. The method is not appli- cable to the holds of large vessels. Formaldehyde is applicable to the disinfection of rooms, clothing, and fabrics, but should not be depended upon for bedding, upholstered furniture, and the like, when deep penetration is required." 164. Many formaldehyde solutions do not contain 40 per cent. of formaldehyde, and all are apt to deteriorate with time. It is there- fore necessary to use a quantity in excess of the amount prescribed in these regulations, unless the solution has been recently analyzed. 165. The following methods of evolving the gas may be used : — (a) Autoclave under pressure, 3 to 13 hours' exposure. (h) Lamp or generator, 6 to 18 hours' exposure. (c) Spraying, 13 to 34 hours' exposure. (d) Formaldehyde and dry heat in partial vacuum, 1 hour's exposure. 166. The minimum number of hours' exposure as given above applies to empty rooms of tight construction containing smooth, hard surfaces; the maximum number of hours' exposure applying in all cases to textiles and other articles of a similar kind requiring more or less penetration. 167. Autoclave under pressure. This method has considerable "It should be noted that formaldehyde disinfection is more efficient in warm, moist or still weather than in cold, dry or windy weather. DOMESTIC QUARANTINE. 511 penetrating power when applied as detailed below. Rooms or apart- ments need no special preparation beyond the ordinary closing of doors and windows. Pasting, caulking, or chinking of ordinary cracks and crevices is not necessary. The doors of lockers and closets and the drawers of bureaus should be opened. In this apparatus use for- malin (40 per cent.), with the addition of a neutral salt, such as calcium chloride (20 per cent.). The gas must be evolved under a pressure not less than 45 pounds. After the gas is separated from its watery solution the pressure may be allowed to fall and steam pro- jected into the compartment to supply the necessary moisture. Use not less than 10 ounces of formalin per 1000 cubic feet, and keep the room closed for three to twelve hours after the completion of the process. For large rooms the gas must be introduced at several points as far apart as possible. It is applicable to the disinfection of clothing and fabrics suspended loosely in such a manner that every article is freely accessible to the gas from all directions. 168. Lamp or generator. This method requires an apparatus producing formaldehyde by a partial oxidation of wood alcohol, and in using it the room or apartment should be rendered tight as prac- ticable. Oxidize 24 ounces of wood alcohol per 1000 cubic feet, and keep the room closed for six to eighteen hours, in accordance with the provisions of paragraph 165. This method leaves little or no odor. When applied to clothing and textiles, the articles should be sus- pended in a tight room and so disposed as to permit free access of the gas. (See also Par. 166.) The wood alcohol should be of 95 per cent, strength, and should not contain more than 5 per cent, of ace- tone. 169. Spraying. The formalin (40 per cent.) should be sprayed on sheets suspended in the room in such a manner that the solution remains in small drops on the sheet. Spray not less than 10 ounces of formalin (40 per cent.) for each 1000 cubic feet. Used in this way a sheet will hold about 5 ounces without dripping or the drops running together. The room must be very tightly sealed in disin- fecting with this process, and kept closed not less than twelve hours. The method is limited to rooms or apartments not exceeding 2000 cubic feet. The formalin may also be sprayed upon the walls, floors, and objects in the rooms. 170. Formaldehyde witli dry heat in partial vacuum. This method has superior penetrating powers and is specially applicable to clothing and baggage. The requirements of this method are (1) dry heat of 60° C. sustained for one hour; (2) a vacuum of 15 512 TEXT-BOOK OF HYGIENE. inches; (3) formaldehyde evolved from a mixture of formalin with a neutral salt, in an autoclave under pressure, using not less than 30 ounces of formalin (40 per cent.) for 1000 cubic feet; and (4) a total exposure, under these combined conditions, of one hour. 171. The stated times of exposure to sulphur dioxide and for- maldehyde are sufficient to destroy bacterial infection due to non- spore-bearing organisms, providing that the infection is present on the surface. If the room is of peculiar construction, so as to impede the diffusion of the gas, or if the room is a dirty one, or if on account of any other condition rendering the germicidal action of the gas more difficult, the time of exposure should be proportionately in- creased, or supplanted by other methods. Chemical Solutions. 172. Bichloride of mercury. Bichloride of mercury is a disin- fectant of undoubted potency and wide range of applicability. It cannot be depended upon to penetrate substances in the presence of albuminous matter. It should be used in solutions of 1 to 1000. The solubility of bichloride of mercury may be increased by using sea water for solution, or by adding 2 parts per 1000 of sodium or ammo- nium chloride to the water employed. 173. Carbolic acid. Carbolic acid in the strength of 5 per cent, (see par. 51) may be substituted for the bichloride of mercury, and should be employed in the disinfection of the cabins and living apart- ments of ships to obviate injurious action on polished metals, bright Avork, etc. 174. Formalin. Formalin containing 40 per cent, of formalde- hyde may be used in a 5-per cent, solution as a substitute for bichlo- ride of mercury or carbolic acid, and is ureful for the disinfection of surfaces, dejecta, fabrics, and a great variety of objects, owing to its non-injurious character. Application of Disinfectants in Quarantine Work. 175. Hold of iron vessel, empty, shall be disinfected by either: — • (a) Sulphur dioxide generated by burning sulphur 5 pounds per 1000 cubic feet of air space, or liberated from 10 pounds of liquid sulphur dioxide, sufficient moisture being present in both cases; time of exposure, twenty-four hours. (See par. 159.) (h) Washing with a solution of bichloride of mercury, 1:1000. 176. Holds of wooden vessels, empty, shall be disinfected by: — DOMESTIC QUARANTINE. 513 (fl) Sulphur dioxide in the manner prescribed above, followed by (&) Washing with a solution of bichloride of mercury. 177. In the case of all vessels, both iron and wooden, when treated for yellow fever or plague infection, the first process shall be a preliminary fumigation by sulphur dioxide in the manner pre- viously stated in paragraph 159-160, in order to insure the destruc- tion of mosquitoes, rats, and other vermin. 178. Holds of cargo vessels, when cargo cannot be removed, shall be disinfected in so far as possible by sulphur dioxide not less than 4 per cent, per vo]ume strength, and where possible this should be gen- erated from a furnace to minimize danger of fire in cargo. 179. Living apartments, cabins, and forecastles of vessels shall be disinfected by one or more of the following methods: — (a) Sulphur dioxide, the destructive action of the gas on prop- erty being borne in mind. (b) Formaldehyde gas. (c) Washing with solution of bichloride of mercury, 1 :1000 or 5-per-cent. solution of formalin, or 5-per-cent. solution of carbolic acid, preference being given to carbolic acid for application to pol- ished woods, bright metals, and other objects injured by metallic salts. The forecastle, steerage, and other living apartments in bad sani- tary condition must be disinfected by method (a) followed by method (c). 180. Mattresses, pillows, and heavy fabrics are to be disinfected by :— (a) Boiling. (&) Flowing steam; {.e.^ steam not under pressure. (c) Steam under pressure. (d) Steam in a special apparatus with vacimm attachment. 181. Clothing, fabrics, textiles, curtains, hangings, etc., may be treated by either of the above methods from (a) to (d) inclusive, as circumstances may demand, or by formaldehyde gas or sulphur dioxide where the article is of a character which will not be damaged by sul- phur dioxide. 182. Articles injured by steam, such as leather, furs, skins, rubber, trunks, valises, hats and caps, bound books, silks, and fine woolens should not l)e disinfected by steam. Such articles should be disin- fected by formaldehyde gas or by any of the agents allowed in these regulations which may be applicable thereto. Those which will be injured by wetting should be disinfected by a gaseous agent. 183. Clothing, textiles, and baggage, clean and in good condition, 33 514 TEXT-BOOK OF HYGIENE. but suspected of infection, can be efficiently and least injuriously dis- infected by formaldehyde gas, generated by one of the methods pre- scribed in paragraph 165 — (a), (h), 0T(d). 184. Textiles which are soiled with the discharge of the sick or presumably are deeply infected, must be disinfected by: — (a) Boiling. (&) Steam. (c) Immersion in one of the germicidal solutions. 185. Cooking and eating utensils are alwaj's to be disinfected by immersion in boiling water or by steam. It is the intention of the act of February 15, 1893, under which these regulations were framed, to have them act uniformly and with- out discrimination against any place, and at the same time to not interfere with the operation of any additional regulations imposed by State or local autho^it3^ MANAGEMENT OF A QUARANTINE STATION. Inspection. — Upon the arrival of a vessel at a quarantine station, during the active quarantine season, she should be boarded without delay, and the following general routine followed, with such modi- fications as may be demanded by the local conditions or dictated by the experience of the quarantine officer. In the event of the arrival of several vessels at the same time, they should, as a rule, be boarded as nearly as possible in the order of their arrival, the rule of "first come, first served" being observed; though it may be remarked that, in the event of the arrival, at nearly the same time, of a vessel carry- ing passengers and one carrying cargo only, there will usuaHy be little opposition on the part of ship-masters if the passenger-ship is in- spected first. Arrived on board, it is well to demand the immediate attendance of the master, not only from the fact that all information must be sought from him, but to impress all concerned with the fact that the authority of the boarding-officer is, for the time, absolute. The master should then be required to produce for inspection his bills of health, the ship's manifest, and the crew- and passenger-lists, if the ship carry passengers. These should be carefully scrutinized, the number of crew and passengers being noted or borne in mind, and note being made of an}'' articles of cargo that come within the pro- scription of the regulations. All special consular certificates bearing on doubtful articles of cargo had better be looked into at this time. A careful inspection of the ship should now follow, particular atten- tion being paid to the condition of the living-apartments of the TREATMENT OF YELLOW-FEVER VESSELS. 515 officers and crew, as their condition of cleanliness or the reverse some- times forms an important index to the cleanliness of the whole ship. The hatches should be removed, and such portions of the cargo as come directly under them be subjected to scrutiny. If the vessel is in ballast, the hold should be entered, explored, and mental note made of the condition of the ship's inner planking or skin, whether dry and sound or rotten and damp. If possible, a limber plank should be lifted, and the condition of the bilges noted. In the comparatively inaccessible places fore and aft there will likely be found deposits of trash and filth, and the chain-lockers should be carefully examined to see whether the cables have been properly washed prior to stowing. The inspection of the ship proper completed, the inspection of per- sons should be entered into. Every person borne upon the ship's papers as passenger or mem- ber of the crew should be personally seen by the boarding-officer or his assistant, and no excuse whatever should be taken for an absence from this muster. In vessels suspected of the infection of plague or yellow fever, the temperature of passengers and crew should be taken to assist in the detection of cases of these diseases in the early stages, and to this end every quarantine station should be supplied with a liberal number of good clinical thermometers. Take nothing for granted, and compel the master to explain any discrepancies between the lists and the actual number presenting themselves for examina- tion. The decision must now be reached whether the vessel goes free under the regulations or is to be detained in quarantine. If the former, the certificate of inspection is filled out, and the master notified that he is at liberty to proceed. If the latter, the vessel is directed to a suitable anchorage, and the yellow quarantine flag is hoisted at the foremast-head. Quarantine procedures proper now begin, and much depends on the nature of the disease quarantined against; the nature and condition of the ship, whether light, in bal- last, or loaded. If there are passengers on board, these are landed, bathed, and assigned to quarters in the barracks. The vessel is laid alongside of the wharf and the disinfecting processes prescribed by the regulations entered upon. TREATMENT OF YELLOW=FEVER VESSELS. A vessel infected with yellow fever is one which has on board actual cases of the disease, or which contains mosquitoes of the genus Stegornyia fasciaia which have had opportunities of biting persons infected with yellow fever, either at the port of departure or upon 516 TEXT-BOOK OF HYGIENE. the voyage. If there are Stegomyia fasciata on board a ship and a case has occurred on board within three or four days, these mosquitoes must be regarded as infected, unless the utmost care has been taken to screen the patients from their attacks. If the ship is from a yellow-fever port, that is to say, where yellow fever actually prevails, and presents Stegomyia fasciata on board, these Stegomjdse are pre- sumably infected, and if as much as twelve days have elapsed on the voyage, are capable of conveying yellow fever to non-immunes. The treatment of yellow fever vessels, therefore, is limited to efforts directed to kill mosquitoes in the living apartments and in the holds of the vessel and to preventing their breeding in places favorable to their development. Various means can be adopted to this end. The burning of sulphur — two pounds per 1000 cubic feet, time of ex- posure twelve hours — is efficacious. If it is apprehended that the sulphur fumes will be injurious or prejudicial to clothing, hang- ings, bright work, polished metal, etc., pyrethrum powder may be substituted for the sulphur, burning one pound per 1000 cubic foot, the time of exposure to be about three hours. Pyrethrum pow- der is not an insecticide; it simply stupefies the insects, and at tlie expiration of this time the room or apartment should be cautiously opened and the stupefied mosquitoes swept up and burned. The use of pyrethrum, therefore, would generally be limited to the living apartments and especially to the cabins of ships; sulphur is safer, more efficacious, and easier of application in the forecastles and holds. Should there be patients sick with yellow fever upon the vessel on the arrival at quarantine, these should be at once removed to the infectious hospital if their condition permits it, and the remainder of the crew and passengers should be inspected twice daily until the time of danger, that is to say, the period of the incubation of the disease, five or six days, has elapsed. In the care and treatment of these passengers detained in quarantine on account of yellow fever, care should be taken to immediately isolate every febrile case and to thoroughly protect it by mosquito netting or wire gauze from the access of mosquitoes until a positive diagnosis is arrived at. If there are no mosquitoes, or care is taken to prevent the infection of mos- quitoes, there will be no spread of the disease. The ballast and cargo of vessels from yellow-fever ports are only dangerous in so far as they may harbor infected mosquitoes. The matter can be summed up in the dictum : "A vessel or a house infected with yellow fever is a vessel or house which contains within its walls infected mosquitoes of the genus Stegomyia fasciata." (Eeed.) TREATMENT OF PLAGUE VESSELS. 517 TREATMENT OF PLAGUE VESSELS. In vessels departing from a port where plague prevails, precau- tions against plague should be commenced at the port of departure. This disease has of late years been robbed of much of its traditional terror, owing to the fact that its cause, its nature, and the methods of handling it in epidemic form have become better understood. In the ordinary or bubonic type of the disease, there is little danger to be apprehended from the patient himself. In the cases pneumonic in- type from their inception, or becoming pneumonic as a secondary infection, the patient is dangerous, as the sputum contains the organ- ism of the disease. The spread of plague seems to be generally effected by means of rats or mice, though insects, such as fleas, bedbugs, ants, etc., may also play a part, not by directly conveying the plague microorganism, but their bites, irritated by scratching, affording an avenue of entrance for the plague bacillus, which may be carried on the bodies or feet of the insects, or possibly conveyed in their dejecta. A most essential precaution in a port infected with plague is to prevent the access of rats, mice, and other vermin on board ship. This is best accomplished by not allowing the ship to approach the dock; but if this is necessary for the purpose of loading, the ship should be breasted off five or six feet from the walls of the dock, and the lines and chains leading ashore should be protected by rat-guards or cones surrounding the lines, their large open ends directed toward the shore. If these are impracticable, or not to be obtained, the lines or chains should be freshly tarred, and, as the rat is more prone to move by night than by day, the gang-ways or planks connecting the ship and the shore should be removed before sunset. A case of plague developing on the voyage should be isolated, and any articles which may be soiled or infected by the patient should be disinfected or, in the absence of means for accomplishing this, should be destroyed. Careful observations should be made upon voyages from plague- infected ports to ascertain any marked sickness or increased mor- tality among the rats which almost always are found on shipboard. Experience has shown that an outbreak of plague in man is almost invarialjly preceded by an increased mortality among rats and mice. Arriving at a quarantine station, vessels infected with plague, or suspecterl of sufh infoctifm, should l)e anchored at a sufficient dis- tance from the shore or from other vessels to prevent the escape of 518 TEXT-BOOK OF HYGIENE. rats by swimming. The personnel of the vessel, passengers and crew, should be subjected to a rigid inspection, if there have been cases of plague during the voj^age, and this inspection should be so conducted that the condition of the glandular regions of the body, the subcer- vical, axillary, and inguinal, may be ascertained. Special attention should be directed to the detection of mild or ambulant cases of the disease, and any case of illness partaking of the nature of a severe bronchitis or of pneumonia should be the subject of a special investi- gation and, if possible, a bacteriological examination. On plague-infected vessels, any of the crew who, in the opinion of the quarantine officer, have been exposed to the direct infection of plague should be bathed, and any of their belongings supposed to have been exposed to infection should be disinfected. Measures should be at once entered into to insure the destruction of rats, mice, fleas, bugs, and even flies and ants, on account of the danger of the spread of infection through their agency. This is best accomplished by a simul- taneous disinfection of the ship by sulphur dioxide. During this process, the escape of rats should be guarded against, and any rats found escaping should be killed by shooting or by means of sticks or other implements. The rats and mice killed by this fumigating process should be gathered, and it is best not to handle them with the naked hands. They should be collected with gloves and their bodies burned, and the spots upon which they have been found dead should be disinfected by actually boiling water or by one of the germicidal solutions, and the vessel should not be considered as free from danger until she is free from rats. The last International Sanitary Conference of Paris, 1903, lent themselves to the declaration that merchandise, in itself, was incapable of conveying the infection of plague, and was only dangerous when soiled or contaminated by plague-stricken rats. Should it be necessary to disinfect a ship in- fected with plague and containing cargo, this disinfection should be conducted in a fractional manner, by removing a portion of the cargo and exposing it to sun and air upon lighters. Sulphur dioxide is then to be generated or introduced into the holds overnight, and dur- ing the next day a further portion of the cargo, not exceeding four to six feet in depth, should be removed. The holds are then closed again and the fumigation is repeated, and this process is continued until all cargo is removed. If the vessel contains no cargo, the holds should be disinfected by sulphur dioxide, dead rats sought for, gathered, re- moved, and burned, and a general disinfection by means of germicidal TREATMENT OF CHOLERA VESSELS. 519 solutions should then follow. The M'ater supply of a vessel plays no role in the dissemination of plague. If the vessel arriving with plague on board has a large number of passengers, these passengers should be removed, segregated into small groups, and held under observation for the period of the incu- bation of the disease, which is now <:'onsidered as about seven days. Those who have been especially exposed to the infection should be segregated by themselves, and should form the subject of careful observation one or more times during the day. Any persons in these groups presenting suspicious symptoms of illness should be removed to the observation hospital ; and if these cases should declare them- selves to be plague of either the bubonic or pneumonic type, they should be at once removed from the suspect to the infectious hospital. The International Sanitary Conference of Paris, 1903, recom- mended that all vessels engaging in passenger travel should be pro- vided with a sufficient quantity of anti-pest serum for the treatment of actual cases of plague and for the immunization of those exposed to its infection. This suggestion is well worthy of serious consid- eration, as the serum is an almost certain prophjdactic and affords the only successful method known of treating actual cases of the malady. TREATMENT OF CHOLERA VESSELS. In the event of the arrival of a ship actually infected with Asiatic cholera, or suspected of such infection, a much more difficult problem confronts the quarantine officer, for the conditions difEer widely from those obtaining in the case of the yellow-fever ship. In a majority of eases the cholera ship carries a large number of passen- gers, a great majority of whom belong to the immigrant class, and the difficulty of handling these is largely increased by the carelessness of their personal habits, their ignorance and disregard of the first laws of personal hygiene, and the discomfort, crowding, and bad sanitary condition of their quarters on board ship. Here many sources of danger must be looked into, and it is almost certain that a disregard of any one of them will be followed by a terrible retribution in the shape of new outljreaks of the disease. The first thing to be done in tlic treatment of a cholera-infected ship is to remove her human freight, and this should be done as rap- idly as is consistent with safety. The occupants of the compartment of the ship in which cholera has appeared shonld receive our first and most careful attention. They must be landed at once, bathed with 520 TEXT-BOOK OF HYGIENE. all possible precaution and thoroughness, furnished with clean, sterile clothing, and isolated in the barracks and regarded as especially dan- gerous. Those actually sick with the disease should be at once car- ried to the contagious hospital, and those sick with any complaint whatever isolated in the suspect hospital pending the determination of the actual nature of their disease. The foregoing applies particularly to the steerage passengers. The question of the treatment of the cabin and saloon passengers is one that will call for all the tact and ingenuity of the quarantine officer, and even then he will be liable to savage criticism and censure through the friends of the cabin passengers detained. It must be remembered that these passengers are luxuriously lodged and catered for with every delicate attention that ingenuity and long experience, sharpened by active competition, can suggest. On board ship they are most carefully guarded from intrusion on the part of the steerage passengers, and, in fact, are as nearly on a separate ship as possible. Is it always necessary to subject these people to the inconveniences and possible hardships that are inseparable from a detention in quar- antine barracks? The answer is that each case must be decided on its individual merits, and much will depend on the extent to which the ship seems infected, the seeming source of the infection, and the facilities which exist on board ship for maintaining a sharp line of demarkation between the steerage and saloon. If, on investigation, it seems that the choleraic outbreak is due to infected food smuggled on board by the emigrants, to infection probably brought aboard in the hand-baggage of the same class of passengers; if, in fine, it would seem to be due to conditions limited to the steerage, it might seem to be the part of wisdom to leave the cabin passengers in their luxurious quarters while the processes of disinfection and detention were in progress. If, on the contrary, the infection seems to be due to a polluted ship's water-supply; if there have been any cases of diarrhoeal disease among the cabin passengers ; if the infection seem to be distributed equally to the steerage and to the saloon, then all must be landed alike, and undergo barrack deten- tion, at least until the disinfection of the ship is thoroughly complete. The barracks for the cabin passengers must, of course, be of a different character from those provided for the steerage. They must be subdivided into small rooms, and, instead of bunks, must be fur- nished with comfortable cots, bedding, and simple, but neat and efficient, toilet facilities. A separate kitchen and table must be pro- vided for this class of passengers, and the whole situation may be SPECIAL MEASURES AGAINST CHOLERA. 521 summed up by saying that the relative difference on shipboard should be preserved on shore during the detention in quarantine. SPECIAL MEASURES AGAINST CHOLERA. Other features of quarantine administration are well expressed in the following extract from the editorial pages of the Philadelphia Medical NeWB of October 15, 1887, showing the measures necessary to extinguish an incipient epidemic of cholera and to prevent its spread. Such measures are as follow : — "(a) Speedy recognition and isolation of the sick; their proper treatment; absolute and rapid destruction of the infectious agent of the disease, not only in the dejecta and vomit, but also in clothing, bedding, and in or upon whatever else it finds a resting-place. "(&) The convalescents should remain isolated from the healthy as long as their stools possibly contain any of the infecting agent; before mingling again with the well they should be immersed in a disinfecting bath, and afterward be clothed from the skin outward with perfectly-clean vestments, which cannot possibly contain any of the infectious material. "(c) The dead should be well wrapped in cloth thoroughly satu- rated in a solution of corrosive sublimate (1 to 500), and, without delay, cortege, or lengthy ceremonial, buried near the place of death in a deep grave, remote as possible from water which may, under any circumstances, be used for drinking, washing, culinary, or other domes- tic purposes. (Cremation, of course, is by far the safest way of dis- posing of cholera cadavers.) "{d) Those handling the sick or the dead should be careful to disinfect their hands and soiled clothing at once, and especially before touching articles of food, drinking, or culinary vessels. "(e) In the case of maritime quarantine, the well should be disembarked and placed under observation in quarters spacious enough to avoid crowding, and so well appointed and furnished that none will suffer real hardships. "(/) Once having reached the station, those under observation should be separated in groups of not more than twelve to twenty-four, and the various groups should, under no pretext, intermingle. The quarters for each group should afford stationary lavatories and water- closots in perfect working condition, adequate to the needs of the in- dividuals constituting the group, and supplied with proper means of disinfection. There should be a bed raised above the floor, proper coverings, and a chair for each member of the group, each person 522 TEXT-BOOK OF HYGIENE. being required to use onl}^ his own bed. There should be a common table of sufficient size to seat around it all the members of the group, who should be served their meals from a central kitchen, and with table-furniture belonging to the station and cleaned by the common kitchen scullions. "(g) Drinking-water, free from possible contamination and of the best quality, should be distributed in the quarters of each group as it is needed, and in such a manner that it is received in drinking- cups only. There should be no water-buckets or other large vessels in which handkerchiefs, small vestments, children's diapers, etc., can be washed by the members of any groujD. "(h) Immediately after being separated into groups in their respective quarters, every person under observation should be obliged to strip and get into a bath (a disinfecting one is preferable), and afterward be clothed with fresh, clean vestments from the skin out- ward. Every article of clothing previously worn should be taken away and properly disinfected. "(i) Then all of the personal effects should be at once removed to a separate building, washed (if possible), and thoroughly disin- fected, or if necessary, destroyed. After disinfection they should be temporarily returned to the members of groups, when occasion re- quires a further change of clothing. "(A-) Under no circumstances whatever should washing of cloth- ing by those under observation be permitted. All used clothing should be first thoroughly disinfected (by boiling, when possible), and then should be cleansed, the disinfection and washing being done by a sufficiently trained and absolutely reliable corps of employees supplied with adequate appliances. ' "(/) All those under observation should be mustered in their own quarters, and be subjected to a close medical inspection, tvMle on their feet, at least twice every day, in order to discover and isolate, as soon as possible, new cases which may develop; and, of course, the clothing and bedding of these new cases should be treated without delay in the manner already mentioned. In the meantime, a watch should be set over the water-closets for the purpose of discovering cases of diarrhoea, and, when discovered, such cases should be tem- porarily separated from the rest. They should receive judicious medical attention at once, and precautions should be taken as if they were undoubted but mild cases of cholera. "(m) The quarters should be kept thoroughly clean, and every surface upon which infectious material could possibly be deposited, SPECIAL MEASURES AGAINST CHOLERA. 523 including tlie floors, slioulcl be waslied with a strong disinfectant twice daily, and oftener when necessary. Evacuations from the bowels should be passed into a strong disinfectant; the hopper of the closet should be then flushed and finally drenched with a quantity of the same disinfectant. "(n) Eor the proper attention to the sick, there should be two or more competent and experienced physicians, assisted by a sufficient corps of intelligent and efficient nurses, with hours of duty so arranged that a physician, with a sufficient number of nurses, shall be in con- stant attendance in the wards of the hospital. "(o) For the prompt recognition and separation of new cases, their temporary medical attention, the proper treatment of discovered cases of diarrhoea or cholerine and of other maladies, and the imme- diate correction of every insanitary practice or condition by constant, vigilant, and intelligent supervision, there should be at least two or more competent and experienced physicians, with hours of service so arranged that a physician is on duty night and day among those under observation; and he should have, subject to his orders at any and every moment, a sufficient and efficient corps of nurses and laborers to carry out properly and promptly his directions. "(jj) In order to prevent the intermingling of the various groups, to enforce obedience and order, and to make it absolutely impossible for the quarantined and their personal effects to have any communi- cation with the exterior, a well-organized and sufficiently large police corps should patrol the borders of the stations and the buildings day and night. ''(q) Any group among whom there have developed no new cases of cholera or of choleraic diarrhoea, during the preceding eight or ten da3^s, may be regarded as harmless, and allowed to leave quarantine after each one is finally immersed in a disinfecting bath and re- clothed with clean garments from the skin outward, the garments removed being destroyed or thoroughly disinfected and cleansed, as already indicated. "As yet no reference has been made to the crew, ship, and cargo. What has been said of the treatment of those under observation ap- plies to every one of the ship's inhabitants. The observation, isola- tion, and cleansing of the crew and their effects could safely be per- formed aboard fhip if necessary. The ship should be thoroughly cleansed and disinfected, particular attention being given to the quar- ters of the emigrants and crew." The following general regulations were promulgated for the gov- 524 TEXT-BOOK OF HYGIENE. ernnient of camps and barracks for the detention of cholera suspects during the summer of 1892 : — - Eegulations foe Cholera Camp. (Prepared in the Marine-Hospital Bureau.) The surgeon in command of the quarantine camp to have abso- lute authority over the police and sanitary regulations of the camp, and to see that they are obeyed. Camp to be divided into two divisions — detention and hospital. Former for housing of suspected cases and well persons from infected localities and the latter for treatment of sick. Detention Camp. 1. Persons destined for this camp to be assigned to specific quarters in tents. First to be subjected to disinfecting bath, and clothed afterward with fresh vestments. Not to leave this camp ex- cept by permission or order of surgeon in command. 2. Persons in detention camp to be inspected twice daily or oftener by medical officer or assistant, while standing, to ascertain any new cases which may develop. 3. New cases of cholera in detention camp to be immediately transferred to hospital camp for treatment, and all their effects dis- infected, as w^ell as the tent in which they may occur. 4. Guards to patrol detention camp night and day, to j)revent intercourse between the two divisions of the camp. 5. Water-supply for entire camp to be boiled for drinking. To be dealt out to each person in cups or glasses for potable purposes. May be acidulated with diluted hydrochloric acid under supervision of a medical officer. 6. If there be room, the detention camp to be segregated into divisions of not more than twenty persons. No intercommunication should be permitted between the groups. 7. All clothing removed from persons entering detention camp to be subjected to steam heat (unmixed with air), not less than 100° C. (212° F.), for one-half hour, or boiling for one hour. Leather and rubber goods to be immersed in 3-per-cent. carbolic-acid solution until thoroughly saturated. 8. The washing of clothing not to be permitted by the detained persons under any pretext. After above disinfection, all laundry- SPECIAL MEASURES AGAINST CHOLERA. 525 work to be then done by the force of employees. The clothing of detained suspects should be kept in separate building after disinfec- tion, and re-issued as required for change. 9. Cleanliness and disinfection of quarters and person to be enjoined and enforced daily. Disinfectants to be used where there is any possibility of infection. 10. At the expiration of five days, if no case of cholera or choleraic diarrhoea has developed in a given group segregated as above, those composing the group may be discharged, after a final disinfec- tion of person and clothing. 11. All water-closets, urinals, privies, or troughs should be pro- vided with latrines similar to those of the cholera camp, and means should be provided for their thorough disinfection before their con- tents are discharged into pits of unslacked lime. 12. Food issued shall be simple, thoroughly cooked, and served at stated hours. ISTo fruit permitted. Hospital Camp. 1. Day sick calls at 8 a.m. and 4 p.m. ; oftener, if necessary. Night call, 12 p.m., by night physician ; oftener, if circumstances require. 2. There shall be one nurse for every hospital tent, who shall be on duty in six-hour watches. Night nurses according to circumstances. Female nurses for cases occurring in that sex. Nurses should be instructed in the necessity of personal hygiene and the sources of infection. 3. Vomited matter and stools to be received into earthen vessels, and at once disinfected with 3-per-cent. solution of carbolic acid or 1 to 500 HgClg combined with 2 parts of HCl to each part of HgCU ; then thrown into a pit of unslacked lime, or discharged into the sea. 4. All soiled linen or clothing that cannot be disinfected to be immediately destroyed by burning. 5. When death occurs, body to be immediately buried, swathed in sheets saturated with 1 to 500 HgClo. Place of interment to be selected to avoid contamination of water-supply. 6. No persons having personal contact with the sick or dead shall leave the hospital camp without practicing disinfection, as specified above. 526 TEXT-BOOK OF HYGIENE. DANGER FROM FLIES IN QUARANTINE. In this article it has been suggested that all dejecta and vom- ited matters of cholera patients be received into vessels containing an efficient germicidal solution; and this is not onlj for the reason that the said dejecta and vomited matters ma}^ infect an}' one who comes into inadvertent contact with them, but has an important bear- ing on the health of those who are resident in the neighborhood of the quarantine station. It has been abundantly proved that the ordi- nary house-fly is capable of conveying in its intestinal tract, for a considerable length of time, living and active cholera spirilla. Know- ing how constantly flies deposit their ordure on articles of food, it can easily be seen how great a menace to public health would be engendered by allowing stools containing the bacilli to remain with- out instant disinfection. The safer plan is, therefore, to not trust to subsequent disinfection, which might be overlooked in the press of other matters, but to receive the dejecta into the germicidal solu- lution so that no time will be lost and no chances of infection may remain. DANGER FROM MOSQUITOES IN QUARANTINE. As the consensus of opinion seems to be that the mosquito Stego- myia fasciata is the sole means for the dissemination of yellow fever, particular attention should be paid to guard patients in quarantine suffering from yellow fever from the attacks of this insect. Not only should the patient be carefully screened by mosquito nets, or bv being kept in apartments rendered mosquito-proof by wire netting, but every effort made to prevent the breeding of this variety of mosquito in the neighborhood of a quarantine station. It is probable that this mosquito is a normal denizen of every quarantine station from the Eio Grande to the capes of A-'irginia, and measures for their pi'even- tion would consist in the thorough screening of all water-containers, water-barrels,' or cisterns, and the filling in of all pools or collections of water which would form favorable places for their breeding and development. The Stegomyia fasciata is essentially a house mosquito and fresh water is necessary for its development. The collections of water which may ordinarily be found about a house, as in wash-bowls, wash- tubs, tin cans, broken bottles, etc., are particularly favorable places for its development, and these should be guarded against at a quar- antine station or in its immediate vicinity. THE NATIONAL QUARANTINE SERVICE. 527 THE NATIONAL QUARANTINE SERVICE. The protection of the United States in the exclusion of quaran- tinable diseases is provided for at the forty national maritime inspec- tion and disinfection stations located in the waterways and ports of entry upon the Atlantic, Gulf and Pacific coasts. The principal sta- tions are as follows : — Perth Amboy, N. J.; Delaware Breakwater Quarantine Station, Lewes, Del. ; Eeedy Island Quarantine Station, Delaware Eiver ; Cape Charles Quarantine Station, Fisherman's Island, Va. ; South Atlantic Quarantine Station, Blackbeard Island, Sapelo Sound, Georgia; Brunswick Quarantine Station, Brunswick, Ga. ; Key West Quar- antine Station, Tortugas Islands, Fla. ; Gulf Quarantine Station, S'hip Island, Miss. ; San Diego Quarantine Station, San Diego, Cali- fornia; San Francisco Quarantine Station, Angel Island, San Fran- cisco Bay, California; and Port Townsend Quarantine Station, Port Townsend, Washington ; Southport, N. C. ; Savannah, Ga. ; Fer- nandina, Jacksonville, Miami, Key West, Punta-Gorda, Cedar Keys, Apalachicola, and Pensacola, Fla., and Astoria, Oregon. DESCRIPTION OF THE NATIONAL QUARANTINE STATIONS ON DELAWARE BAY AND RIVER. It may prove of interest to briefly describe a national quaran- tine station, and no better example can be found than the stations at Delaware Breakwater and at Eeedy Island, Delaware Eiver. These stations, while in a measure separate and distinct, are intended to work in connection with each other and to afford complete protec- tion against the importation of contagious and infectious disease through the medium of the commerce which seeks the port of Phila- delphia and the ports of entry on Delaware Bay, and situated in the States of Delaware, New Jersey, and Pennsylvania. At the station at Delaware Breakwater, which is situated at the mouth of Delaware Bay and immediately upon the point formed by Cape Henlopen, is the reservation, forty acres in extent, and surrounded by a substantial picket-fence ten feet in height. Within this enclosure is located the quarantine plant proper, consisting of commodious hospitals for con- tagious and non-contagious diseases, and barracks for the accommo- dation of one thousand suspects, fitted with bunks and provided with bedding and a full supply of clothing for both males and females. In conneclion with these barracks are a large kitchen, fully equipped 528 TEXT-BOOK OF HYGIENE. with steam cooking-apparatus of the most improved description and a commodious mess-halL There has been also provided a building containing a boiler for operating the pumps, a bath-house, and laun- dry, which latter is equipped with appliances for washing all soiled clothing and for subjecting them to the boiling process. In this building there is also located a steam disinfecting chamber of the most modern and improved type, and adjoining this building is a bath-house fitted with twenty shower- and two tub-baths, all pro- vided with hot and cold water. An artesian well has been sunk, capable of supplying twenty thousand gallons of water per day, and this water is raised by a powerful pump to elevated tanks, and from these distributed to the barracks, kitchens, hospitals, laundry, and bath-house. Latrines are provided and furnished with iron containers hold- ing a strong disinfecting solution, and provision is made for empty- ing these containers into a sewer, which, in turn, empties into a sewer common to the bath-house and laundry, which discharges into the sea. The danger of soil contamination by alvine discharges is reduced to a minimum, and the water-supply likewise protected. Outside of the fence is a large brick house, which furnishes executive and admin- istrative offices and quarters for the medical officers on duty at the station. In front of the executive building is a lofty flag-staif, which affords the means for communicating by signals with vessels in quar- antine and arriving in the offing. Within a few hundred yards of the reservation is a long iron pier, which affords ample facilities for the landing of passengers. Situated fifty-five miles above the Breakwater, and forty-five miles from Philadelphia, is the Eeedy Island Quarantine Station, on and near the island of that name. Upon the island itself are situ- ated the residence of the medical officer, quarters for employees, and a cottage hospital. A boat-house is connected with the island by a gangway. The quarantine plant proper is located on a pier situated on the edge of the channel, and in thirty feet of water. The pier is two hundred feet in length, and presents a frontage of nearly four hundred feet, owing to the placing of an ice-break above and below the pier. This affords room for the accommodation of the largest vessels, and upon the wharf is situated the disinfecting plant, consisting of two steam chambers ; a sulphur-furnace, fan and engine for driving the same; tanks for disinfecting solutions and a pump and hose for their distribution ; a fire-pump, and tanks for the storage of water for fire and steaming purposes. THE NATIONAL QUARANTINE SERVICE.- 529 There are only small barracks at this station, it being the plan that the vessel shall receive quarantine treatment at this point, and that the passengers shall undergo their detention in the barracks at the Breakwater station. Another national station which deserves special notice from its peculiarities is the quarantine vessel Jamestown, which can be con- sidered a floating quarantine station. The Jamestown was turned over to the U. S. Marine-Hospital Service by the ISTavy Department for quarantine use. She is one of the old-fashioned sailing-vessels of the nav}^ is very strongly and solidly constructed, and is one hundred and sixty-six feet long, thirty-six feet beam, and has a displacement of eight hundred and eighty-eight tons. She has been fitted for her present use by being housed in, and there- have been placed on board a steam disinfecting chamber, a sulphur-furnace, tank for bichloride solution, and bath-rooms. In addition to these, she has been fitted as a place of detention for tAvo hundred and fifty to three hundred immigrants, and is in all respects a complete quarantine station, and capable of doing valuable service in smooth water. AIDS TO NATIONAL QUARANTINE. In aid of the national quarantines, sanitary inspectors are ap- pointed by the Marine-Hospital Service at special points of danger, either in the United States or abroad. Through the State Depart- ment consular notification from foreign ports is received regularly by mail, or, in emergency, by cable, and the information thus received, and that received also from home ports, is communicated, by the Marine-Hospital Bureau, to all quarantine authorities, and others, by means of a weekly publication known as the "Public Health Eeports." An important source of information concerning the movements of vessels in every portion of the world is the "Maritime Eegister," published in New York. The United States Collectors of Customs are efficient aids, having, by law, the power of search and detention of vessels, and having exceptional knowledge of the sanitary condi- tion of the shipping at their respective ports. The Eevenue-Cutter Service, a national coast patrol, gives frequent and efiicient aid; the Light-house Establishment and Coast Survey render valuable assist- ance in locating and buoying the anchorages, and the Life-Saving Service, with its constant patrol of the coast, guards against the entry of a vessel at an unusual point. The surf-men are required to rake together and destroy dunnage and other material likely to be infected that have been tlirown overboard and washed ashore from infected 34 530 • '.TEXT-BOOK OF HYGIENE. vessels. Finally, the Marine-Hospital Service, having, besides the quarantines, the care of the sick of the merchant vessels of the United States, with one hundred and twenty-six physicians stationed at the larger and many of the smaller ports, is ready at a moment's notice to extend indefinitely its quarantine service. NATIONAL INSPECTION OF ALL QUARANTINES. The Act of Congress approved February 15, 1893, while con- templating that State and local quarantines shall not be disturbed in the exercise of their functions, provided said quarantines are ad- ministered in accordance with the law and the regulations made there- under, further provides that the rules and regulations of local quar- antines shall be examined by the Surgeon-General of the Marine- Hospital Service, and also that such additional rules and regulations as may be deemed necessary shall be made by the Secretary of the Treasur}^, and shall be enforced by the State or local quarantine au- thorities. If the latter refuse, or are unable to enforce them, the law further provides that the President of the United States shall detail or appoint an officer for this purpose. To carry out the intent of this law all the quarantines of the United States, national. State, and local, are inspected periodically by an officer of the Marine-Hospital Service. Following are the instructions prepared for the inspecting officers : — Instructions to Medical Officers of the Marine-Hospital Service Detailed to ]\Iake Inspections of State and Local Quarantines. Treasury Regulations. * * * * * * * * * In the performance of the duties imposed upon him by the act of February 15, 1893, the Supervising Surgeon-General of the Marine- Hospital Service shall, from time to time, personally or through a duly-detailed officer of the ]\Iarine-Hospital Service, inspect the mari- time quarantines of the United States, State and local, as well as national, for the purpose of ascertaining whether the quarantine regu- lations prescribed by the Secretary of the Treasury have been, or are being, complied with. The Supervising Surgeon-General, or the officer detailed by him as inspector, shall, at his discretion, visit any incoming vessel, or any vessel detained in quarantine, and all por- tions of the quarantine establishment for the above-named purpose, NATIONAL INSPECTION OF ALL QUARANTINES. 531 and with a view to certifying, if need be, that the regulations have been, or are being, enforced. — J. Gr. Carlisle, Secretary. General Instructions. A. Your inspections will include all ports within your district where vessels are allowed to enter and discharge cargo, and ports which may be used as ports of call. B. A separate report will be made of each station visited. C. Visit every part of the quarantine establishment, and take necessary precautions to prevent the conveyance of contagious or in- fectious disease through the medium of your own person. D. Visit the custom-house for the purpose of ascertaining whether the regulations with regard to bills of health and quarantine certifi- cates are being observed; also, the immigration station for any perti- nent information. E. Reports of a statistical character and descriptive of the quar- antine, called for herein, need be made but once in every six months, namely, on the date nearest the 1st of January and the date nearest the 1st of July; but any changes that have been made since the last general report should be immediately recorded. In making your report you will follow the special instructions in their order, referring to each by number. Special Instructions. 1. Describe the quarantine station, location, buildings, anchor- ages, etc. Give limits of anchorage for non-infected and for infected vessels; facilities for inspection of vessels; apparatus for disinfec- tion of vessels and of baggage; facilities for removal and treatment of the sick, and for the removal and detention of suspects ; mail and telegraph facilities, etc. 2. Give personnel of the station or port; name of the quarantine officer or officers; post-office address; total number of officers and subordinates, etc. 3. Transmit copies of the laws under which the local quarantine is maintained, and copies of the quarantine regulations; also describe the quarantine customs of the port as they are carried out. Note. — There are sometimes slif^ht, but possibly important, variations from the letter of the local refrnlations in the administration of quarantine. Also, local rcfjulations (generally allow a wifle latitude to the quarantine officer, and how this latitude is used — i.e., how the quarantine oflfieer inter- prets the spirit of the rcj^ulations — is very important. 532 TEXT-BOOK OF HYGIENE. 4. State what quarantine procedures, either under printed regu- lations or by customy are enforced at the port, in addition to the requirements of the Treasury Department. It should also be stated whether there is undue or unnecessary detention or disinfection of vessels. 5. State whether the inspection is maintained throughout the year or for what jjeriod, and what treatment of vessels is enforced during the entire year. 6. Are vessels from other United States ports inspected? 7. Describe quarantine procedures in the inspection of vessels, and, if infected, the treatment. Give time in quarantine (a) between arrival and commencement of disinfection, {b) time occupied by dis- infection, and (c) time after completion of disinfection of vessels until discharge. Note. — Quick or slow handling of a vessel is of more importance com- mercially than the question of fees. The time lost is the vessel's heaviest expense, generally. 8. What communication is held with vessels in quarantine (and, before quarantine, by pilots, etc.), and how regulated? Is there any intercommunication allowed among vessels in quarantine? 9. State what will be done with a vessel infected with cholera; second, a vessel infected with yellow fever; third, a vessel infected with small-pox (said vessels carrying or not carrying immigrants), and what conditions are regarded as giving evidence of the vessel's infection in each case. 10. State whether records are kept, at the station, of the cases of disease that have occurred during the voyage, on arrival and during detention, 11. Transmit schedule of quarantine fees, and give other fees and expenses necessarily and usually attendant on quarantine, as tonnage, ballast, wharfage charges, etc. 12. Make a statement showing the number of vessels arriving at the port during the preceding calendar year, by months, (a) from foreign ports; (&) from foreign ports in yellow-fever latitudes via domestic ports; (c) from domestic ports. Show, also, the character of the commerce carried on by the port — i.e., from what countries chiefly the vessels come, and whether in cargo, ballast, or empty. 13. State results of your visit to {a) the Custom-house; (&) the Immigration Bureau. 14. State whether, in 3'our opinion, the quarantine facilities are sufficient to care for the shipping entering the port. INLAND QUARANTINE. 533 15. JSTame the quarantine regulations of the Treasury Depart- ment which are not properly enforced, and state specifically whether the regulations regarding inspection and disinfection, and particularly the period of observation after disinfection, of vessels are observed. 16. Mention any facts which, in your opinion, should be known to the Department, bearing directly or indirectly upon the quarantine service, and make such recommendations as seem proper. — Walter Wtman, Surgeon-General. Note. — Report to be written on legal-cap paper (on one side only), signed, and inclosed in this blank as a cover. INLAND QUARANTINE. Under Inland Quarantine will be described The Sanitary Cordon, Camps of Probation, Eailroad Quarantine, Disinfection Stations, and Inspection Service. THE SANITARY CORDON. This consists of a line of guards, military or civil, thrown around a district or localit}^, either to protect the same from the surrounding country when infected, or to protect the surrounding country from the infected district or locality. When a given locality is infected, and the adjacent territory is regarded as suspicious, it may be necessary to establish a double cordon, the first one embracing the whole suspected territory at its outer edge, the second investing more closely the well- defined infected locality. After the expiration of a sufiicient time to prove that the area between the cordons is not infected, or has been cleared of infection, the first cordon may be removed. Hospitals and camps of probation may be necessary adjuncts to the cordon. The most noted example of the sanitary cordon is found in the history of the plague-epidemic in Eussia in 1878. A colony on the river Volga, called Wetljankaja, with a population of 1700 inhabitants, Ijecame infected with the Oriental plague, which extended to the neighboring villages. A military cordon was made to embrace all the infected district. The inhabitants of the focus of infection, Wetljankaja, were removed, property appraised for re-imbursement by the government, and the village burned. An additional cordon was thrown around Zarizin, a neighboring commercial city of impor- tance and terminus of the I'ussian railway system. The cordons were maintained several months, and the plague was stamped out. (See Abstract Sanitary I'eports, vol. i [Bulletin's], page 78.) The sani- 534 TEXT-BOOK OF HYGIENE. tary cordon is the customary method of preventing the spread of epidemic disease in the eastern countries. In the United States, when yellow fever prevailed in Pensacola, in 1882, to the extent of 3300 cases, the navy-yard reservation, whose boundary-line is within two miles of the city limit, and with a popu- lation of about 1500, was successfully guarded by means of a cordon and non-intercourse. The following year, 1883, the navy-yard itself was infected, and a cordon was thro'WTi around it to protect the city of Pensacola, and was maintained for a period of sixty days. This cordon was under the management of the Surgeon-General of the Marine-Hospital Service, aid having been requested of the national government. The Collector of Customs of Pensacola was made the agent to execute the orders of the Marine-Hospital Bureau, and to the President of the local Board of Health was intrusted the immediate command of the line and guards. The cordon entirely surrounded the land-boundary of the naval reservation. Its line was four miles in length, one mile of it through a dense thicket, and was marked by blazed trees and flags. Forty men were employed as guards, an equal number being selected from each of the two political parties. Two captains were appointed, and were obliged to supervise the line night and day. The sentinel posts were furnished with tents, and two guards were allotted to each post, taking alternate watches of four hours each. A detention or probation camp was established and placed in charge of a physician, where persons wishing to leave the reservation were obliged to pass a probationary period of twenty days. Not more than half a dozen persons were received in this camp. The govern- ment expended about $20,000 in these restrictive measures, which were entirely successful. Not one person got through the cordon line. The success was due largely to the thorough discipline maintained by the Collector and the President of the Board of Health. Yellow-fever Cordon in Texas. — In 1882, yellow fever prevail- ing in Mexico, along the Eio Grande, and in Brownsville, Texas, a sanitary cordon was established by the Surgeon-General of the Marine- Hospital Service, on request of the Governor of the State, extending along the line of the railroad from Corpus Christi, on the Gulf of Mexico, inland to Laredo, on the Eio Grande. This line was one hundred and eighty miles northeast of Brownsville, the triangular territory thus hemmed in by the cordon on one side, the Eio Grande on another, and the Gulf on the third, being all suspected territory, although the fever prevailed in only one corner of it — viz. : in Browns- INLAND QUARANTINE. 535 ville. All persons were detained at least ten days at the cordon before being allowed to pass northward — a period of probation to insure that no one having the disease should carry it farther north. As soon as practicable another cordon was established much nearer to Browns- ville, only thirty miles from it, the line extending from the mouth of the Sol Colorado, on the Gulf of Mexico, to Santa Maria, on the Eio Grande. After a time sufficient to prove that no more fever prevailed between the two cordons, the first one was removed. Within the second line, where the fever prevailed, chiefly in Brownsville, a hospital was established and dispensaries opened for the gratuitous treatment of all applicants. Upon the Mexican side of the Eio Grande the fever continued to spread northwardl}^, and, in order to oppose it, still another cordon had to be established on the American side of the river, extending from Santa Maria on the south to Laredo on the north, a distance of five hundred miles. Three hundred guards, well mounted (Texan cow-boys), were employed in this cordon, and, while the disease was being stamped out in Brownsville, any further importation from Mexico was thus prevented. In Mexico the fever continued to spread until the authorities finally adopted measures similar to the above. The epidemic of yellow fever in Brunswick, Ga., in 1893, gave rise to the necessity of establishing a sanitary cordon to protect the surrounding country from the danger incident to the ]3anic-engen- dered flight of the inhabitants of that town. On account of the peculiar situation of Brunswick the difficulties to be met were very great. Not only were numerous roads to be guarded, but three water- passages from the city into the surrounding country had also to be watched. The cordon, therefore, partook of the nature of both a land and water patrol, and the difficulties were successfully overcome, and no well-authenticated instances of escape through the lines were estab- lished. Much violent language has been used concerning the hardships imposed by the sanitary cordon, but in the presence of an epidemic the authorities who are responsible need to pay more heed to the efficiency of the cordon than to individual complaints. It should be borne in mind that the sanitary cordon is not intended to bottle up all the people who are caught within an infected district. On the contrary, it is intended as a means of exit to those who will not carry with them contagious disease to the people bej'oud. The cordon, then, imposes simply a period of detention corre- sponding to the incubative pei'iod of the prevailing disease. Ample 536 TEXT-BOOK OF HYGIENE. preparation must be made for housing and feeding, in camps or other quarters, persons awaiting the expiration of the detention period ; and hospitals must be provided for the treatment of those who develop sickness. Provision must also be made for the disinfection of sus- pected baggage. CAMPS OF PROBATION. Camps of probation or detention should be established with all the precision of arrangement and regard for site, water, and drainage that pertain to a military camp. Every effort should be made to make the camp as comfortable and cheerful as possible, and to this latter end amusements and entertainments such as might be suggested by the campers themselves should be encouraged. Every necessity in the matter of food, bedding, and the ordinary comforts of life should be anticipated, to prevent any just cause of complaint. Such a nat- ural division of the inhabitants should be made as seems desirable at the time, those of equal intelligence and refinement naturally seeking each other's company. The greatest concern is to prevent the camp itself from becoming infected. To this end no baggage should be allowed within the camp-boundary without previous examination or fumigation, to ensure its freedom from mosquitoes ; and every refugee should be examined by a physician before being admitted to the camp. jSTo one should be received who does not intend to proceed to an im- infected locality after his probation. In other words, a camp of probation should not be used as one of refuge. The camp must be surrounded by guards to prevent egress or ingress, excepting through the established portal. At least twice or three times in the twenty-four hours all refugees should be inspected in their quarters, and any case of sickness at once be isolated and watched and screened from mosquitoes until the diagnosis is certain. If the case is one of the prevailing disease, the patient must be re- moved immediately to the hospital, which should be at a safe distance, half a mile or more, from the camp. Before leaving the camp, cloth- ing should be fumigated to destroy mosquitoes, and he should be given a certificate that he has passed the required period of probation. A clear distinction must be made between camps of probation and camps of refuge. Camps of refuge are simply residence camps established to receive the population of an infected community, Avhen it has been determined to depopulate the infected district. Depopulation of a house, a block, a district, or a whole city, if possible, the people moving into camps, is now reco,o;nized as a valu- INLAND QUARANTINE. 537 able means of controlling an epidemic ; and there may be either camps of probation or simply camps of refuge, or both, according to the requirements of the situation. Camps of refuge, in connection with depopulation, were suggested by the late Surgeon-General Woodworth, in 1878, and the measure was practically carried out at Memphis, in 1879, by the establishment of Camp Mitchell. "But the establish- ment of a camp to which persons from infected points could go, be kept under observation a sufficient length of time to demonstrate they were not infected, have their baggage disinfected, and be given 'free pratique,' is apparently a new departure in inland quarantine." Camp Perry, Fla. — Such was Camp Perry, Florida, described by the surgeon in charge, W. H. H. Hutton, in the Marine-Hospital Service Report for 1889. The site was admirably chosen by Passed Assistant Surgeon John Guiteras, upon a bluff on the south side of St. Mary's Eiver, the dividing line between Florida and Georgia, about forty miles north of Jacksonville, Fla., which city was in the throes of a yellow-fever epidemic. The camp was opened August 20, 1888. It consisted, in its completed stage, first, of 50 wooden cottages built elsewhere and transported on cars. Their dimensions were 12 feet by 10, and 10 feet in height, constructed of plain lumber, with cracks battened, and windows on each side with swinging shutters. Each held four cots, chairs, and toilet-stand, while unused clothing was neatly arranged on the rafters above. Besides the 50 cottages there were a quartermaster and guard-house, commissary building, dining- room and kitchen, and laundry, built of rough lumber; 2 Ducker portable barracks, each 18 by 35 feet, provided with 12 beds each, and 350 tents, used principally by the single men, the employees and guards, and the colored refugees. So far as known, this is the first camp of the kind ever established ; at least, in the United States. The cottages were arranged in a quadrangle around a parade-ground two acres in extent, and the tents were arranged in streets and alle3'^s in the rear of the cottages. The accommodations were sufficient for 600 people, and extra tents were on hand so that, if required, 1000 persons could have been provided for, or 3000 per month, allowing for only ten clays' detention of each person. Two himdred hospital tents will accommodate 1200 people comfortably, according to Sur- geon Hutton, wbo states that the small A-tents are unsuited for women and children, but will answer for men or boys. Wire-mattress cots should be provided. The Marine-Hospital officer at Savannah, Ga., was the purchasing agent for the camp, and promptly forwarded all subsistence supplies on requisition by mail or telegraph. 538 TEXT-BOOK OF HYGIENE. Discipline of the Camp. — On arrival of a train, each passenger was personall}^ examined by a physician, his health-certificate scruti- nized, and he was made to await the examination of others. Hand- bags, clothing, and loose wearing-apparel were left in the baggage-car for disinfection. The refugees were then conducted to the quarter- master's room for registration and assignment to quarters. On first arrival they were placed in the southern part of the camp, and in two days, there being no sickness, Avere moved forward several cabins, and this progression was repeated until the time for discharge. Twelve guards were employed, under the command of a captain, and were divided into squads of four each. The schedule was so arranged that each guard was on duty two hours and off duty four. A bugler announced the several calls, as follow: — 5.30 A.M Reveille. 6.00 A.M Breakfast, employes. 7.00 A.M Breakfast, guests. 9.00 A.M Surgeon's call and inspection. 12.00 M Dinner, employes. 1.20 P.M Dinner, guests. 4.30 P.M Surgeon's call and inspection, 5.30 P.M Supper, guests. 6.00 P.M Supper, employes. 6.30 P.Jr Retreat and change of guard. 9.00 P.M Retiring taps. The yellow -fever hospital camp, under the special charge of Dr. Faget, was located one-half mile from the probation camp. It con- sisted of 2 frame buildings, 2 hospital and 12 smaller tents, arranged in a double-crescent shape, the avenue in the middle presenting an attractive appearance. Of the 12 small tents, 4 were for nurses, 3 for emploj^ees, 2 for convalescents, and 1 each for drug-store, storage- and dead-house. One of the hospital tents was used as a dining-room for employees, convalescents, and parents of the sick. The hospital was established' September 3, 1888, and between that date and November 24th 35 cases of yellow fever were admitted and treated, 3 died, and 32 were discharged. Twelve hundred and eleven refugees were received into Camp Perry, nearly all of whom were from the infected district of Jacksonville. Thirty-five cases of yellow fever were caught by the ten days' detention, but no case of fever was contracted at the camp, and of the 1208 refugees who passed the required detention and proceeded to different parts of the country, so far as known, not one subsequently INLAND QUARANTINE. 539 developed or carried the disease elsewhere. The general plan of the preventive measures adopted during this epidemic will be described under Eailroad Quarantine. Detention Camp, Waynesville, Ga. — The epidemic of yellow fever in Brunswick, Ga., in 1893, caused the establishment of another camp of probation near Waynesville, Ga. Following is the report of the medical officer in command : — "Sir: I have the honor to present the following report of the operations of the detention camp near Waynesville, Ga. "The camp was officially opened for the reception of refugees from Brunswick, Ga., on the 18th of September, 1893, and closed by the order of Surgeon, E. D. Murray, Marine-Hospital Service, per- mitting the return of all refugees to their homes in Brunswick, No- vember 30, 1893. "Four hundred and thirty-one persons availed themselves of the privileges of the camp, of whom about two hundred and twenty-five were white and the remainder black and colored. "The site of the camp was selected by Surgeon W. H. H. Hutton, and was twenty-three miles west of Brunswick, immediately upon and on the south side of the Brunswick and Western Eailway, and upon an eminence about twenty-five feet above the level of the surrounding countrjr, which is generally swampy, and within a mile of the margin of what is locally known as the Buffalo Swamp. As is usual in this section, the elevation was covered with a dense growth of yellow-pine, scrub-oak, and black-gum trees. The soil was a gray, sandy loam, overlying a stratum of yellow clay, and the natural drainage of the site in all directions was good. "On my arrival I found that, under the direction of Surgeon Hutton, an area of two hundred feet had been cleared of trees and undergrowth, and at the four corners of this square rough but sub- stantial buildings had been erected, which were used, respectively, as kitchen, white and colored dining-rooms, guard-room, quartermaster's store-room, executive office, telegraph office, and commissary. A depot and baggage-room were provided at the railway. Along the lines con- necting these buildings, at intervals of twelve feet, were placed wall- tents, twelve by fourteen feet, with flies, and subsequently further rows of tents were pitched behind these and opening on streets four- teen feet wiflo. All tents were provided with substantial floors raised six inches above the ground, and the following equipment was pro- vided: For each inmate, one spring, wire-bottomed cot, one cotton mattress, one hair pillow, two sheets, one pillow-case, and, for each 540 TEXT-BOOK OF HYGIENE. tent, two tin wash-bowls, two tin cups, and two wooden chairs. Ee- markable ingenuity was displaj^ed by the inmates in the construction of articles of furniture from packing-cases, waste lumber, etc. The tents proved of good quality in service, and quite comfortable in all weather. It is suggested, however, that any future tents be constructed with a wall two feet higher and of one foot greater pitch. A hospital establishment of two buildings was provided at a distance of one-half mile from the camp. A lofty pine-tree was fitted with a topmast, and served as a staff for the display of the national colors from sunrise to sunset each day. "The following routine was observed, the calls being given by the bugle : — 5.30 A.M Reveille and attendants' breakfast. 6.00 A.M Breakfast. 8.00 A.M Sick call. 12.00 M Dinner. 4.00 P.M Sick call. 5.00 P.M Supper. Sunset Retreat and call to quarters. 9.00 P.M Tattoo. 9.15 P.M Taps (extinguish lights). "The meals were substantial, abundant, and as varied as possible. In all cases women and children were served at the first table, and the races were served in separate diningrroomsr "The following rules were announced, and seemed to work well in practice : — "1. At reveille all inmates will rise and prepare for breakfast. "2. All quarters must be clean, floors swept, and beds made up before first sick call. "3. Meals will be served in the dining-rooms only, and at stated hours, and no meals shall be carried from the dining-rooms to any quarters, except upon the written order of the medical officer, renewed from day to day, "4. At sick calls all inmates will repair to their quarters, and be there visited and inspected by the medical officer, who will prescribe or advise as he may deem best. "5. All suspicious cases of disease will be isolated at once, and until such time as the nature of the same may be determined. "6. All cases of infectious disease will be treated only in the hos- pital provided for the purpose. "7. 1^0 baggage from infected localities shall be brought into camp until disinfected by such process as may be directed, and only INLAND QUARANTINE. 541 such wearing-apparel as may be deemed absolutely necessary will be brought into camp after the disinfecting process. "8. All wearing-apparel shall be a second time disinfected before discharge from camp. "9. Any person taken ill between two sick calls shall at once notify the nearest guard, who will, in turn, at once notify the medical officer. "10. Guards are enjoined by their vigilance to prevent the com- mission of any nuisance near any quarters; should such nuisance be discovered, the inmates of the nearest quarters will be required to police the same under the supervision of the guard, who will make report of the same. "11. Inmates will confine themselves to the inner lines of the camp after retreat (sunset) call. "12. While innocent enjoyment will be encouraged, the strictest propriety of conduct will be demanded and enforced. "The discipline of the camp was, in the main, good throughout. But two confinements for misbehavior were required during the entire duration of the camp. "All baggage was submitted to steam disinfection upon arrival at and departure from camp. The apparatus used was devised by Surgeon H. R. Carter, Marine-Hospital Service, and was constructed in a baggage-car, the steam being supplied by a locomotive. "In addition to other duties, nearly sixteen hundred cars, boxes, and fiats were disinfected for the B. and W. Railway, sulphur fumi- gation being used for the boxes and drenching with acid solution of bichloride of mercury (1 to 800) for flat cars. This disinfection of cars enabled the traffic into Brunswick to be carried on with a mini- mum of delay and hardship. "Two cases of yellow fever occurred among the inmates of the camp, one resulting in recovery, one in death. Both cases occurred in the persons of sailors who had arrived in Brunswick on vessels trading there, and both would seem to show a period of incubation of at least five days, thus justifying our detention of ten days." THE INFLUENCE OF THE MOSQUITO UPON THE MANAGEMENT OF YELLOW FEVER. Such was formerly the routine of the management of detention and probation camps. With the aflvance of definite knowledge on tli(; siibjfct of the etiology and metbods of conveying yellow fever, 542 TEXT-BOOK OF HYGIENE. this would be modified in certain particulars where the camp is in- tended for the prevention of the sj^read of yellow fever. The disin- fection of baggage from the place infected with yellow fever would no longer be required further than to insure the destruction of mos- quitoes that might be contained therein; and the methods for the prevention of yellow fever within the camp from eases arising in inmates after entry would be limited to screening them from the access of mosquitoes and to the elimination of places and conditions favorable to the multiplication of the Stegomyia fasciata. THE MANAGEMENT OF EPIDEMICS OF YELLOW FEVER IN THE LIGHT OF THE MOSQUITO TRANSMISSION OF THE DISEASE. As may be well imagined, the promulgation of the mosquito doc- trine of the transmission of yellow fever, and its general acceptance by scientists and sanitarians, has necessitated some radical departures in the handling of epidemics of yellow fever. Whereas it was for- merly considered . that fomites were the principal agent in the dis- semination of the infection, it is now generally recognized that these articles play absolutely no role in the transmission of the disease, and that measures for the suppression of an epidemic must be based upon the destruction of the mosquito of the genus Stegomyia fasciata and the shielding of actual cases of yellow fever from the attacks of these insects. It seems to be accepted that if there are no mosquitoes of this genus, or if such mosquitoes are not allowed to bite individuals sick with yellow fever, there will be no spreading of the disease. The following extracts from publications of the Public Health and Marine-Hospital Service show clearly the basis upon which restrictive epidemic measures are founded, and the report of the management of the epidemic of yellow fever in Laredo, Texas, and at various points along the Texas-Mexican border in 1903, give a clear idea of the practical application of measures founded upon this doctrine. Par from making the work of the sanitarian more easy, this doc- trine has necessitated more rigorous care even than was formerly necessary, and it is easy to see that a failure to recognize cases early, to screen them from the bites of mosquitoes, or to destroy mosquitoes and the places favorable for their breeding, will be followed by disas- trous results in the shape of a spread of the epidemic. Cases of yellow fever plus the existence of mosquitoes of the genus Stegomyia fasciata INLAND QUARANTINE. 543 will always mean more cases of the disease. Absolute shielding of cases of the disease from the attacks of mosquitoes, and the destruc- tion of the breeding places of such mosquitoes, will result in a dis- appearance of the epidemic. In fact, were all febrile cases of what- ever nature protected from the attacks of the insects, and were mos- quitoes not allowed to propagate by careful and rigorous attention to the accepted methods for their destruction, there need be no spread of the disease; but a failure in any minute particular to follow out these two principles would render any efforts for the suppression of the epidemic largely negatory. It is notoriously a matter of difficulty to recognize cases of yellow fever in a city or locality where the disease has not recently pre- vailed in epidemic form, and therefore too much stress cannot be laid upon the necessity of screening all febrile cases until a positive diag- nosis can be made. This applies equally to the conveyance of malarial fevers by mosquitoes of the genus Anopheles^ as to j^ellow fever by the Stegomyia. Not only is the mosquito dangerous to the public health, but the malarial or yellow fever patient is prejudicial to the Ano- pheles or Stegomyia by infecting it prior to rendering it a vehicle for the transmission of infection. The infection of yellow fever is only contained in the blood of the yellow-fever patient during the first three or four days of the malady, and by this time the nature of the illness can usually be determined. THE CAMPAIGN OF PROPHYLAXIS AGAINST YELLOW FEVER ON THE TEXAS=MEXICAN BORDER, 1903=04. The epidemic of 1903 having ended, it became necessary, in view of sanitary and climatic conditions, to inaugurate a vigorous cam- paign of prophylaxis along the Texas-Mexican border and in all places in Texas where the disease had prevailed during 1903, to guard against a recrudescence of the fever in the spring of 1904. "A sanitary inspection of the territory situated in the triangles between San Antonio, Laredo, Corpus Christi, and Brownsville was inaugurated and officers detailed to investigate the conditions along the lines of railway travel to detect any possible recrudescence of the disease. A campaign of instruction, showing the methods of drain- age, destruction of mosquitoes, oiling of water-containers, etc., and the screening of all yellow fever patients, was carried out, supple- mented with aid in fumigation of premises, etc., where requested, and no doubt the generally satisfactory condition of affaire at this time 544 TEXT-BOOK: OF HYGIENE. (September 30, 1904) is due to this earl}- anticipatory sanitary cam- paign in aid of the State and local authorities. "In addition to the measures already enumerated, it was con- sidered advisable as a precautionary measure to prepare, pack, and store small camp outfits at five points upon the Louisiana-Texas border, thereby saving time in shipment should an emergency arise. These camp outfits were accordingly stored at the selected points." It is pertinent to add that the measures were entirely successful, no yellow fever making its appearance in Texas during the summer of 1904. RAILROAD QUARANTINE AND INSPECTION SERVICE. Eailroad quarantine and inspection service may be described by a brief account of the actual measures of this nature made use of during the yellow-fever epidemic in Florida, in 1SS8, of which Camp Perry, just described, was an important adjunct. (For details, see annual reports Marine-Hospital Service, 1888 and- 1889.) The Governor of Florida made fipplication to the national au- thorities, July 16th, for aid, and it was determined to prevent further spread of the disease by disinfecting all baggage from infected locali- ties before permitting its transportation into other States, and by enforcing, upon all persons from infected localities seeking to leave the State, a probationary detention of ten days. Accordingly, disinfection stations were established at two points, through which all persons leaving Florida by rail were obliged to pass. One of these was at Live Oak, in jSTorthwestern Florida; the other at Way Cross, Georgia, near the boundary-line of ISTortheastern Florida. The only other means of egress from the State was from the sea- ports ; but healthy sea-ports maintained a vigorous quarantine against people from the infected districts, and infected sea-ports were not visited by the steam-ship lines, because their vessels would thereby be made liable to quarantine detention at other ports. The fumiga- tion of baggage at Live Oak and Way Cross was accomplished by means of box-cars specially prepared, and subsequently in warehouses, the agent being sulphur dioxide. Eegarding persons, the inspectors, properly uniformed and wear- ing official shields, boarded the trains when the latter arrived at the inspection stations, and demanded of each passenger a certificate, showing where he had been during the previous ten days, Avhich cer- tificate was considered valid only when it bore the seal or signature of some officer of health, or recognized municipal authority. The in- INLAND QUARAXTTNE. 545 specters themselves were kept informed regarding all infected or sus- pected localities, and a person coming from such locality was either made to return to it or given the option of going to the camp of pro- bation, there to spend the ten days' period of probation before being allovs^ed to enter other States. This was Camp Perry, previously described, located 38 miles south of the Way Cross Station, and 40 miles north of Jacksonville, where the epidemic prevailed chiefly. All egress from Jacksonville was, perforce, through Camp Perry and its ten days' probation. This camp was a means of protecting not only other States, but the uninfected portions of Florida itself, more particularly Southern Florida, whose health authorities refused to admit within their limits the refugees from the infected districts unless they had passed the period of probation at Camp Perry. To assist in this protection to Southern Florida, no person was allowed to board a south-bound train between Way Cross, on the north, and Orange Park, a station 20 miles south of Jacksonville. Moreover, through south-bound trains were boarded at Way Cross, and all passengers compelled to furnish evidence of coming from healthful localities. The evidence consisted of certificates from local authorities, baggage-checks, or railroad-tickets showing they were pur- chased in the North, and in some instances letters showing by the superscription and stamps where the person had been. ISTo train, excepting the special government train, was allowed to stop at Camp Perry. A government train also carried those who had passed the period of probation from Camp Perry to a point Syo miles distant, Folkstone, where they were transferred to a regular train running as far north as Way Cross, Ga., where another transfer had to be made to a regular north-bound train. Xo Florida passenger- car was allowed to go north, and more than 1000 baggage- and freight- cars were disinfected by government officers before being allowed to leave the State. Train-inspection Service during the Brunswick Epidemic. — Dur- ing the Brunswick epidemic the following regulations for the inspec- tion of trains were promulgated and enforced: — "Inspectors will allow none to board a train, unless with a cer- tificate, between Way Cross and Savannah. "If certificate can be examined before boarding, without deten- tion to train, it must be done, and those which are unsatisfactory will not be allowed to board. "After boarding, the certificate and the person must be carefully 546 TEXT-BOOK OF HYGIENE. examined and the inspector assure himself that the passenger is not recently from Jesup or any infected locality. "If the passenger is known to be a recent resident of Jesup or any infected locality, or to have been in such place during the past two (2) weeks, he will not be allowed to board, even if he has a cer- tificate, o "If, after boarding, either the certificate or the examination of passengers is not satisfactory, the passenger will be turned over to the city authorities at Way Cross or Savannah, or at the place where he desires to stop. If between these places, the facts to be noted and reported. "A record will be kept of the names of all passengers inspected, name of signer of certificate and his rank, date of inspection, date of certificate, and place of boarding train ; and where passenger is bound and what disposition is made of him, whether passed or turned over to local authorities; also any other facts worth notice. "Inspectors will aid local quarantine authorities in any way in their power consistent with their duties, and give them any informa- tion, obeying all local quarantine regulations. Inspectors report to Surgeon Carter, United States Marine-Hospital Service, or A. P. English, M.D." The methods of railroad quarantine may also be studied in a review of the action taken to prevent the introduction of small-pox into the United States from Canada, where it prevailed extensively in the fall and winter of 1885, and January and February, 1886. The following regulations were issued by the Surgeon-General of the Marine-Hospital Service, October 10, 1885 : — "The act approved April 29, 1878, entitled "An act to prevent the introduction of contagious or infectious diseases into the United States,'' provides that no vessel or vehicle coming from any foreign port or country where any contagious or infectious disease exists, or any vessel or vehicle conveying persons, merchandise, or animals affected with any contagious disease, shall enter any port of the United States, or pass the boundary-line between the United States and any foreign country, except in such manner as may be prescribed under said act. "Attention is now directed to the prevalence of the contagious and infectious disease of small-pox in Montreal and other places in the Dominion of Canada, and the law referred to is held to apply alike to trains of cars and other vehicles crossing the border, and to vessels entering ports on the northern frontier. INLAND QUARANTINE. 547 "Because, therefore, of the danger which attaches to the trans- portation of persons and baggage, and articles of merchandise, or ani- mals, from the infected districts, the following regulations are framed, under the direction of the Secretary of the Treasury, and subject to the approval of the President, for the protection of the health of the people of the United States against the danger referred to : — "1. Until further orders all vessels arriving from ports in Canada, and trains of cars and other vehicles crossing the border-line, must be examined by a medical inspector of the Marine-Hospital Service before they will be allowed to enter the United States, unless provision shall have been made by State or municipal quarantine laws and regu- lations for such examination. "2. All persons arriving from Canada, by rail or otherwise, must be examined by such medical inspector before they will be allowed to enter the United States, unless provision has been made for such examination. "3. All persons coming from infected districts, not giving satis- factory evidence of protection against small-pox, will be prohibited from proceeding into the United States until after such period as the medical inspector, the local quarantine, or other sanitary officer duly authorized, may direct. "4. The inspectors will vaccinate all unprotected persons, who desire or are willing to submit to vaccination, free of charge. Any such person refusing to be vaccinated shall be prevented from entering the United States. "5. All baggage, clothing, and other effects, and articles of mer- chandise, coming from infected districts, and liable to carry infection, or suspected of being infected, will be subjected to thorough disinfec- tion. "6. All persons showing evidence of having had small-pox or varioloid, or who exhibit a well-defined mark of recent vaccination, may be considered protected; but the wearing-apparel and baggage of such protected persons who may come from infected districts, or have been exposed to infection, will be subjected to thorough disin- fection as provided. "7. Customs officers and United States medical inspectors will consult and act in conjunction with authorized State and local health authorities so far as may be practicable, and unnecessary detention of trains or other vehicles, persons, animals, baggage, or merchandise, will be avoided so far as may be consistent with the prevention of the 548 TEXT-BOOK OF HYGIENE. introduction of disease dangerous to tlie public healtli into the United States. "8. Inspectors will make full weekl}^ reports of services performed under this regulation. "9. As provided in Section 5 of said act, all quarantine officers or agents acting under any State or municipal system, upon the appli- cation of the respective State or municipal authorities, are empowered to enforce the provisions of these regulations, and are hereby author- ized to prevent the entrance into the United States of any vessel or vehicle, person, merchandise, or animals prohibited under the act aforesaid. "10. In the enforcement of these regulations there shall be no interference with any quarantine laws or regulations existing under or to be provided for by any State or municipal authority." The following are the special instructions for the guidance of sanitary inspectors, issued by Surgeon H. W. Austin, in charge of the inspection service on the Canadian frontier from Buffalo, N. Y., to the Atlantic coast during the epidemic above referred to (see Marine- Hospital Eeport, 1886) :— Eegulations for Sanitary Inspectors, "The following instructions will be observed by the sanitary in- spector on the following-mentioned railroads crossing the United States boundary-line — viz., the Grand Trunk Railway, at Eouse's Point, N. Y., and Island Pond, Vt. ; the Passumpsic Railroad, at iSTewport, Yt. ; the Central Vermont Railroad, at Uighgate Springs or Saint Albans; the Canada Atlantic, at Rouse's Point, N. Y., and the Southeastern Railway, at Richford, Yt. : — "All persons bound for the United States coming from Montreal, or other places in Canada where small-pox prevails, must produce satisfactory evidence to the inspector that they are protected by a recent vaccination, or submit to this operation before they are allowed to cross the boundary-line. "Inspectors will vaccinate all unprotected persons free of charge. "Persons coming from Montreal, or suburban villages, will be carefully questioned as to their residence, whether small-pox has occurred in their families, or whether they have been in contact with the disease. "Inquiries should also be made relative to their baggage, whether it consists of bedding, household goods, etc., likely to be infected ; and INLAND QUARANTINE. 549 if any person or article of baggage is considered by the inspector in- fected or likely to introduce the disease into the country, he or it should not be permitted to cross the line into the United States. "You may consider persons protected who may show evidence of having had the small-pox or varioloid, or who exhibit a well-defined mark of vaccination. Accept as evidence of protection a certificate from any physician in good standing that the person presenting the same has been successfully vaccinated. Should 3'ou doubt the validity or authenticity of the certificate, you may refuse any such person presenting the same the privilege of crossing the border unless he submits to vaccination. Baggage known to have come from any in- fected district, and believed to be infected, will be thoroughly fumi- gated with sulphur at Eouse's Point, Saint Albans, Richford, ISTew- port, and Island Pond. 'Weekly reports should be made to Surgeon H. W. Austin, United States Marine-Hospital Service, Burlington, Vt., of the num- ber of trains inspected, number of persons examined, number of per- sons vaccinated, number of pieces of baggage fumigated, and any other information relative to services performed by the inspector.'' It will be observed that all the railroads, five in number, over which passengers or freight might be brought direct from Canada into the 'New England States, were guarded. Besides the line commanded by Surgeon Austin (Atlantic coast to Buffalo), another line was under the direction of Passed Assistant Surgeon Wheeler, at points east of Buffalo, and still another on the Michigan frontier, under command of Surgeon W. H. Long. These lines were established at the request and with the co-operation of the authorities of the respective States. Thirty-six inspectors were em- ployed at 37 stations, who examined 49,631 persons on railroad-trains, vaccinated 16,547, and detained or sent back 603. The contents of more than 7000 pieces of baggage were disinfected. The measures taken were successful. In 1893, at a time when there was imminent danger that cholera might be introduced into the sea-board cities of the United States and carried by immigrants to the far West and the interior cities and towns, a most carefully formulated plan of railroad medical inspec- tion of immigrants was drawn up; and while it was, fortunately, never necessary to carry out Ihe provisions made at the time, the fol- lowing regulations will m-gII show the scope and general design of the protective and restrictive measures contemplated: — 550 TEXT-BOOK OF HYGIENE. Eailroad Medical Inspection of Immigrants. Treasuey Department, Office of the Supervising Surgeon-General United States Marine-Hospital Service, Washington, August 23, 1893. Instructions for the Guidance of Medical Officers of the Marine-Hos- pital Service, Sanitary Inspectors, and other's concerned. 1. One or more medical inspectors shall accompany immigrants from the point of departure of each immigrant train, and shall im- mediately commence making a careful inspection of every passenger — ■ man, woman, and child — upon the train. This inspection shall consist in identifying each passenger with the health card or cards he or she may hold, and satisfying himself as to the health of each person at the time of said inspection. He shall pass through the train once every hour or oftener, if he has reason to believe any person is suffering with diarrhcea or other symptoms of cholera. 2. The railroad companies will be expected to furnish earth- closets, which should be used, and the regular closets of the car are to be locked. These earth-closets shall be destroyed, before the train reaches it destination, at such points as the railroad officials shall designate. It shall be the duty of the inspector to see that the earth- closets are kept clean and frequently disinfected, and the cars prop- erly ventilated and free from all offensive odors and dirt. 3. He shall, upon the least suspicion of cholera among the im- migrants, have the suspected person or persons immediately removed to the hospital car at the rear of the train, disinfect all ejecta, and take every precaution possible to prevent the spread of the disease among the passengers by thoroughly disinfecting that portion of the car occupied by the suspects, the simplest means for this purpose being a solution of bichloride of mercury in the proportion of 1 to 800. 4. The inspectors will at once notify the conductor of the train upon the first appearance of a suspicious case, in order that the hos- pital car may be switched off at the first designated switch, and the health officer of the county in which said switch is located be imme- diately notified to take charge of this car. 5. It is expected that the railroads will furnish a car for hospital purposes, in which the seats can be readily converted into beds suit- able for the care of the sick. The necessary bedding will be furnished by the United States Marine-Hospital Service. 6. Disinfectants, consisting of packages of bichloride of mercury INTERSTATE QUARANTINE. 551 and an alkali, will be furnished the medical inspector in proper quan- tities for adding to a two-gallon wooden bucket of water ; also a quan- tity of carbolic acid in solution and other approved disinfectants. Each hospital car shall be equipped with a dozen two-gallon wooden buckets for holding disinfecting fluids, half a dozen mops, one or more hand force-pumps with rose sprinklers, one or more commodes and bed-pans, half a dozen eight-ounce hard-rubber sj^ringes, half a dozen tumblers, one dozen rubber sheets, and one dozen feeding-cups for administering medicine. There shall also be furnished an oil-stove for heating water, and several tin boilers and tin cups. 7. Medical supplies, etc., consisting of tannic acid, hydrarg. chlo- ridum mite, tincture of opium, mustard or mustard papers, chloro- form or ether sulph., whisky, brandy, and one or more hypodermic syringes; also supply of Squibb's Diarrhoea Mixture for checking looseness of the bowels or premonitory diarrhoea. Walter Wyman, Supervising Surgeon-General. INTERSTATE QUARANTINE. The general principles governing interstate quarantine are the same as those pertaining to the maritime and foreign quarantines, with the exception that, instead of dealing with ships as the media of transportation, we must deal with trains on railroads, lines of stage-coaches, and steam-boats plying on the inland waters of the United States. The principles are almost sufficiently elaborated in the previous sections on train inspection in the case of yellow-fever epidemics, and the precautions which were under consideration for the prevention of the spread of cholera by means of emigrant trains. An important matter is the one of notification. It will be seen, by a study of the regulations for interstate quarantine which follow, that State and municipal health officers are requested to notify the Supervising Surgeon-General of the appearance of any of the quar- antinable diseases in their States or localities, thus enabling appro- priate measures to be taken to prevent their spread without the loss of valuable time, for time in the management of epidemics is of the utmost importance. Many an epidemic which has assumed vast pro- portions would, if recognized in time, have been capable of easy man- agement and of being confined to the seat of its first outbreak. It is always comparatively easy to confront an open enemy; it is the in- sidious spread of disease, either unrecognized or concealed for reasons 552 TEXT-BOOK OF HYGIENE. of business polic}^, that causes delay in the inception of preventive measures, and is most to be dreaded from a sanitary standpoint. The following are the regulations prepared in the Marine-Hos- pital Bureau to prevent the introduction of contagious diseases into one State or Territory or the District of Columbia from another State or Territory or District of Columbia. It is expected that additional regulations will be promulgated from time to time as circumstances demand : — Interstate Quaeantine. article i. quarantine diseases. 1. Tor the purpose of these regulations the quarantinable diseases are cholera (cholerine), yellow fever, small-pox, typhus fever, leprosy, and plague. ARTICLE II. — NOTIFICATION. 1. State and municipal health officers should immediately notify the Supervising Surgeon- General of the United States Marine-Hos- pital Service, by telegi-aph or by letter, of the existence of any of the above-mentioned quarantinable diseases in their respective States or localities. ARTICLE III. — GENERAL REGULATIONS. 1. Persons suffering from a quarantinable disease shall be iso- lated until no longer capable of transmitting the disease to others. Persons exposed to the infection of a quarantinable disease shall be isolated, under observation, for such a period of time as may be nec- essary to demonstrate their freedom from the disease. All articles pertaining to such persons, liable to convey infection, shall be disinfected as hereinafter provided. 2. The apartments occupied by persons suffering from quaran- tinable disease, and adjoining apartments, when deemed infected, together with articles therein, shall be disinfected upon the termina- tion of the disease. 3. Communication shall not be held with the above-named per- sons and apartments, except under the direction of a duly-qualified officer. 4. All cases of quarantinable disease, and all cases suspected of belonging to this class, shall be at once reported by the physician in attendance to the proper authorities. 5. No common carrier shall accept for transportation any person INTERSTATE QUARANTINE. 553 suffering with a quarantinable disease, nor any infected article of clothing, bedding, or personal property. Bodies of persons who have died from any of the said diseases shall not be transported save in hermetically-sealed coffins, and by the order of the State or local health officer. 6. In the event of the prevalence of small-pox, all persons exposed to the infection, who are not protected hy vaccination or a previous attack of the disease, shall be at once vaccinated or isolated for a period of fourteen days. 7. During the prevalence of cholera, all the dejecta of cholera patients shall be at once disinfected, as hereinafter provided, to pre- vent possible contamination of the food- and water-supply. ARTICLE IV. — YELLOW FEVER. In addition to the foregoing regulations contained in Article I, the following special provisions are made with regard to the preven- tion of the introduction and spread of 5'ellow fever: — 1. Localities infected with yellow fever, and localities contiguous thereto, should be depopulated as rapidly and as completely as pos- sible, so far as the same can be safely done ; persons from non-infected localities, and who have not been exposed to infection, being allowed to leave without detention. Those who have been exposed, or who came from infected localities, shall be required to undergo a period of detention and observation of ten days, from the date of last exposure, in a camp of probation or other designated place. Clothing and other articles capable of conveying infection shall not be transported to non-infected localities without disinfection, i.e., inspection to determine the presence of possibly infected mosquitoes, and appropriate measures of fumigation to destroy them. 2. Persons who have been exposed may be permitted to proceed without detention to places willing to receive them, and incapable of becoming infected, when arrangements have been perfected to the satisfaction of the proper health officer to insure their detention in said places for a period of ten days. 3. The suspects who are isolated under the provisions of para- graph 1, Article III, shall be kept free from all possibility of infection. 4. So far as possible the sick should be removed to a central loca- tion for troatment. 5. Buildings in which yellow fever has occurred, and localities believed to be infected with said disease, must be disinfected as thor- oughly as possible. 554 TEXT-BOOK OF HYGIENE. 6. As soon as the disease becomes epidemic, the railroad-trains carrying persons allowed to depart from the city or place infected with yellow fever shall be under medical supervision. 7. Common carriers from the infected districts, or believed to be carrying persons and effects capable of conveying infection, shall be subject to sanitary inspection, and such persons and effects shall not be allowed to proceed, except as provided for by paragraph 2. 8. At the close of an epidemic the houses where sickness has occurred, and the contents of the same, and houses and contents that are presumably infected, shall be disinfected as hereinafter prescribed. ARTICLE V. DISINFECTION". For Cholera. 1. The dejecta and vomited matters of cholera patients shall be received into vessels containing an acid solution of bichloride of mer- cury (bichloride of mercury, 1 part; hydrochloric acid, 2 parts; water, 1000 parts) or other efficient germicidal agent. 2. All bedding, clothing, and wearing-apparel soiled by the dis- charges of cholera patients shall be disinfected by one or more of the following methods : — (a) By complete immersion for thirty minutes in one of the above-named disinfecting solutions. (&) By boiling for fifteen minutes, all articles to be completely submerged. (c) By exposure to steam at a temperature of 100° to 102° C. for thirty minutes after such temperature is reached. 3. Any woodwork or furniture contaminated by cholera dis- charges shall be disinfected by thorough washing with a germicidal solution as provided in paragraph 1, Article V. For Yellow Fever. 4. Apartments infected by occupancy of patients sick with yellow fever shall be disinfected by one or more of the following methods : — {a) By thorough washing with one of the germicidal solutions mentioned. If apprehension is felt as to the poisonous effects of the mercury, the surfaces may, after two hours, be washed with clear water. (&) Thorough washing with a 5-per-cent. solution of pure car- bolic acid. INTERSTATE QUARAXTIXE. 555 (c) By sulphur dioxide, twenty-four to forty-eight hours' expo- sure, the apartments to be rendered as air-tight as possible. 5. Bedding, wearing-apparel, carpets, hangings, and draperies infected by yellow fever shall be disinfected by one of the following methods : — (a) By exposure to steam at a temperature of 100° to 103° C. for thirty minutes after such temperature is reached. (h) By boiling for fifteen minutes, all articles to be completely submerged. (c) By thorough saturation in a solution of bichloride of mer- cury, 1 to 1000, the articles being allowed to dry before washing. Articles injured by steam (rubber, leather, containers, etc.), to the disinfection of which steam is inapplicable, shall be disinfected by thoroughly wetting all surfaces with (a) a solution of bichloride of mercury 1 to 800, or (&) a 5-per-cent. solution of carbolic acid, the articles being allowed to dry in the open air prior to being washed with water, or (c) by exposure to sulphur fumigation in an apart- ment air-tight, or as nearly so as possible. (Recent investigations have proved that in disinfection for yellow fever less attention need be paid to fomites, but more to the exter- mination of mosquitoes.) For Small-pox. 6. Apartments infected by small-pox shall be disinfected by one or both of the following methods : — (a) Exposure to sulphur dioxide for twenty-four to forty-eight hours. (b) Washing with a solution of bichloride of mercury 1 to 1000, or a 5-per-cent. solution of pure carbolic acid. 7. Clothing, bedding, and articles of furniture exposed to the infection of small-pox shall be disinfected by one or more of the fol- lowing methods : — (a) Exposure to sulphur dioxide for twenty-four to forty-eight hours. (h) Immersion in a solution of Inchloride of mercury 1 to 1000, or a o-per-cent. solution of pure carbolic acid. (x) Exposure to steam at a temperature of 100° to 102° C. for thirty minutes after such temperature is reached. (d) Boiling for fifteen minutes, the articles to be completely submerged. 556 TEXT-BOOK OF HYGIENE. For Typhus Fever. 8. Apartments infected by typhus fever shall be disinfected by one or both of the following methods : — (a) Exposure to sulphur dioxide for twenty-four to forty-eight hours. (&) Washing with a solution of bichloride of mercury 1 to 1000, or a 5-per-cent. solution of pure carbolic acid. 9. Clothing, bedding, and articles of furniture exposed to the infection of typhus fever, shall be disinfected by one or more of the following methods : — (a) Exposure to sulphur dioxide for twenty-four to forty-eight hours. (&) Immersion in a solution of bichloride of mercury 1 to 1000, or a 5-per-cent. solution of pure carbolic acid. (c) Exposure to steam at a temperature of 100° to 102° C. for thirty minutes after such temperature is reached. {d) Boiling for fifteen minutes, the articles to be completely sub- merged. (Lately fumigation with formaldehyde gas has taken the place of sulphur dioxide.) MUNICIPAL QUARANTINE. It is now generally conceded that a small number of cases of certain ones of the quarantinable diseases may exist in a city of con- siderable size, without giving rise to serious apprehension, if intelli- gent and vigorous measures for the prevention of its spread are taken, and if scientific measures for the isolation of patients, the surveillance of those exposed to infection, and the disinfection of apartments and articles infected are carried out. It is regarded as very important that the sick should be removed to centrally-located hospital estab- lishments for treatment, thus increasing ease of management and administration, and diminishing the number of foci of infection. The surveillance of those exposed to infection should, in general, be for a period of time equal to the usual period of incubation of the disease to which they have been exposed. In the case of small-pox it may be unnecessary at times to detain the suspects the full period of in- cubation, provided they are vaccinated and their clothing and per- sonal effects are rendered safe by efficient disinfection. They should, however, be kept under observation. For the suppression of small-pox in cities in which it has made MUNICIPAL QUARANTINE. 557 its appearance, and in which it threatens to become epidemic, the following suggestions, made by the health authorities of the North- west, will undoubtedly prove of value: — 1. The city should be divided into districts containing not more than 10,000 people. 2. Each district should be placed under the supervision of a com- petent medical inspector with necessary assistants (a) to make a house-to-house inspection; (b) to successfully vaccinate, within the shortest possible time, all persons who have not been vaccinated dur- ing the outbreak, the first vaccination to be completed within seven days; (c) to properly disinfect all houses and their contents where small-pox occurs. 3. Necessary means and appliances for efficient disinfection of materials, premises, etc., should be provided as the exigencies of each district may require. 4. Each case of small-pox should be immediately removed to a suitably constructed and properly equipped and officered isolation hos- pital. 5. Except in extreme cold weather, hospital tents, as prescribed in the United States Army Eegulations, floored and warmed, are preferable to the average hospital or private dwelling, and increase the chances of recovery of the patients. Cases of small-pox neces- sarily retained in their own homes should, with their attendants, be rigidly isolated during the period of danger, and physicians visiting such patients professionally should be subject to such regulations as may be prescribed by the local health officer. 6. Persons exposed to small-pox contagion should be immediately vaccinated and kept under observation for not less than fourteen days from time of last exposure. 7. It is the sense of this Conference that unless such measures are enforced, it will be necessary for neighboring cities and States to exclude all persons from such city who are not protected against small- pox by recent vaccination, and to require proper disinfection of all clothing, baggage, and merchandise capable of conveying small-pox infection. The subject of municipal quarantine naturally suggests a sub- division of the subject, viz., domiciliary quarantine, or the exercise of restrictive measures against a particular house or part of a house on account of the occurrence of a quarantinable disease within its limits. These can best be accomplished by the stationing of guards to see that none enter or leave llio infected premises except those necessary to 558 TEXT-BOOK OF HYGIENE. care for the sick, viz., physicians and nurses. All intercourse between the outside world and the house under quarantine should be carried on by messengers who should not be allowed to enter the premises, but who should report to the guards. It would be most desirable that the physicians and nurses, on leaving the premises, should practice personal disinfection of hands, at least; though, of course, it would be better if, in addition to this, a change into sterile clothing Avere made prior to coming into contact with the public. It goes without saying that the room of the patient should be absolutely closed to the ingress of all save the physicians and nurses, and it is a practice of considerable value to provide all room-openings with curtains or hangings, which are to be kept constantly wet with a germicidal solution. The dejecta, vomited matter, and sputum should be promptly disinfected according to circumstances. When the disease has terminated, the house or aj^artments are to be thor- oughly disinfected by one of the methods prescribed in the regula- tions, the method chosen being adapted to the disease which has pre- vailed. For the purposes of municipal disinfection the Marine-Hos- pital Service has had constructed portable apparatus for the use of steam and sulphur, which are, in effect, the same apparatus as have been previously described in this article, modified to meet their special requirements. An important factor in the measures taken to suppress any epi- demic disease is a house-to-house inspection, to ascertain the actual number of cases existing. Whether this inspection should include the whole city, or only the infected district, is a matter for the exercise of judgment; but, when required, the inspections should be made at intervals corresponding with the usual periods of incubation of the disease under observation. A very important field for the exercise of municipal and domi- ciliary quarantine is furnished by those contagious and infectious diseases which, while causing large mortality, seldom prevail in epi- demic form, viz., measles, scarlet fever, diphtheria, and tuberculosis. MEASLES. Measles may be dismissed with a few words. The course of the disease, uncomplicated, is usually so benign, especially in children, that all that is necessary is isolation. At the conclusion of the case or cases the apartment should be well aired, and it may be advisable DIPHTHERIA AND SCARLET FEVER. 559 to subject the room and the contents, bedding, and clothing to fumi- gation by sulphur or formaldehyde. DIPHTHERIA AND SCARLET FEVER. With diphtheria and scarlet fever the conditions are far different. The diseases are virulent: the infection is subtle, and their spread very much to be dreaded. Vigorous effort alone can prevent their spread. Dwellings where the disease prevails must be placarded, spe- cial hospitals should be provided, and disinfection should be intelli- gently performed by competent municipal authority. The regulations of the Board of Health of the District of Co- lumbia are given here, as embodying the more recent practice in the management of these diseases : — Eegulations to Prevent the Spread of Diphtheria and Scarlet Fever. "The following regulations, provided for in the Act of Congress approved December 30, 1890, are promulgated for the information of all concerned :— "The act referred to provides, in Section 2, 'That it shall be the duty of the health officer, in conjunction with the attending physician, to cause the premises to be properly disinfected, and to issue the necessary instructions for the isolation of the patient; in Section 3, 'That it shall be the duty of physicians, while in attendance upon cases of scarlet fever and diphtheria, to exercise such reasonable pre- cautions to prevent the spread of the said diseases as may be prescribed by the health officer of the District of Columbia in regulations'; in Section 6, 'That the word "regulations," as herein used, shall be held to mean, also, rules, orders, and amendments.' "The term 'scarlet fever,' as applied in the act, shall be held to include scarlatina, scarlet rash, and canker rash, and each and every case must be reported upon the forms provided. "Warning-signs shall remain displayed on houses, in cases of scarlet fever, for a period of not less than four weeks, and in cases of diphtheria for not less than three weeks from date of report to the health officer, and for a longer period, unless report of recovery by the physician in attendance has been made. "In cases of death, the warning-sign shall remain displayed upon premises for a period of not less than seven days, and longer, unless the health officer is satisfied that all proper means liuve been employed for provontion of the spread of tlie contagion. 560 TEXT-BOOK OF HYGIENE. "It shall be the duty of the householder,- in every case where a warning-sign has been displayed from the premises which he or she occupies, to report promptly the removal of such sign at any time within the periods given. "It shall be the like duty of the physician in attendance to make such report to the health officer of the removal of warning-signs, unless assured that the report has been made by some one from the premises where the disease is prevailing or has prevailed. "It shall be the duty of the physician in attendance to report, in every instance, on the forms provided, whether or not children in the family or other children in the same building attend school, and at what school-building or buildings. "Children shall not be permitted to return to school from in- fected premises, except upon presentation of the proper certificate from the health officer. "All persons suffering from either diphtheria or scarlet fever are to be isolated in rooms as far removed as possible from those occupied by other persons in the building, and upon the top floor, where it is practicable. No person, other than the physician in attendance, the examining official, and the nurse or nurses, shall be admitted to such room during the prevalence of the disease. "Every room occupied by a patient suffering from either diph- theria or scarlet fever shall be cleared of all needless clothing, carpets, drapery, and other materials likely to harbor the poisons of the disease. "Soiled bed- and body-linen shall be immediately placed in ves- sels of water containing a solution of bichloride of mercury, chloride of zinc, or other suitable, disinfectant. "Excremental discharges from the patient shall be received in vessels of water containing such a solution, and all vessels used shall be kept scrupulously clean and thoroughly disinfected. "Discharges from the throat, nose, and mouth shall be received upon pieces of cloth, which must be immediately burned. "All persons recovering from either diphtheria or scarlet fever shall be considered dangerous, and shall not be permitted to associate with others, or to attend school, church, or any pixblic assembly, until a certificate has been furnished by the health officer to the effect that they may go abroad without danger of disseminating the contagion. "It shall be the duty of the person in charge of the premises where a case of diphtheria or scarlet fever exists, to exercise all rea- sonable care in the prevention of the commingling of persons who DIPHTHERIA AND SCARLET FEVER. 561 come into contact with the patient, or any other persons, whereby the contagion might be disseminated. "The body of a person who died from either diphtheria or scarlet fever shall be immediately disinfected and placed in a coffin, which shall be tightly closed, and shall not be taken to any church or place of public assembly, and shall be buried within forty-eight hours, unless otherwise ordered by the health officer. "No public funeral shall be held in a dwelling in which there is a case of either diphtheria or scarlet fever, nor in which a death from either of said diseases has recently occurred. "Immediately upon the recovery of a person who has been suf- fering from either diphtheria or scarlet fever, or upon the death of a person who has been so suffering, the room or rooms occupied shall be thoroughly disinfected by exposure for several hours to the fumes of chlorine gas, or of burning sulphur, and shall thereafter be thor- oughly cleaned and exposed to currents of fresh air. "All clothing, bedding, carpets, and other textiles which have been exposed to the contagion of the disease shall be either burned, exposed to superheated steam, or thoroughly boiled. "No person shall interfere with or obstruct the entrance, inspec- tion, and examination of any building or house, by the inspectors or officers of this department, when there has been reported the case of a person sick with either scarlet fever or diphtheria therein." Biagnosis of Diphtheria.- — For the more prompt and certain diagnosis of diphtheria, small wooden boxes are distributed to the various pharmacies in Washington, each box holding two glass tubes, one tube containing a small cotton swab, the other containing solidi- fied blood-serum as a culture medium. Each tube is sterilized and plugged with cotton. The following notice is inclosed in each box : — Directions for Making Cultures in Suspected Cases of Diphtheria. "The patient should be placed in the best light attainable, and, if a child, properly held. In cases where it is possible to get a good view of the throat, depress the tongue and rub the cotton swab gently, but freely, against any visible pseudomembrane or exudate.''^ "In other cases, including those in which the exudate is confined to the larynx, open tlie mouth and pass the sM'ab Ijack till it reaches ''This fihoiild be dono before any germicide has been applied, and, if thin has hcen done, allow at h^ast an hour to intervene l)efoie making the inofiilatiori. 562 TEXT-BOOK OF HYGIENE. the pharynx, and then rub it freely against the mucous membrane. Without laying the swab down, withdrew the cotton plug from the culture-tube, insert the swab, and rub that portion of it which has touched the exudate gently back and forth along the surface of the blood-serum. Then replace the swab in its own tube, plug both tubes, and send the whole outfit at once to the laboratory. "A report will be forwarded the following morning, by mail, or can be obtained by telephone." TUBERCULOSIS. With the discovery by Koch of the cause of tuberculosis, and the numerous researches made by him and other observers into the nature of the tuberculous poison, has growTi conviction, of late years, that tuberculosis, being communicable, is to a large extent preventable. The hacillus tttherciilosis. is the etiological factor of most importance in the spread of tuberculosis ; it has been proved that it is contained in large numbers in the sputum of tuberculous patients, and that, unlike most microorganisms, its vitality is not destroyed by drying. Therefore, with the careful disinfection or destruction of the ex- pectoration of tuberculous patients, one most important factor in the dissemination of tuberculosis will be removed. In almost all large hospitals, at the present day, the practice obtains of either isolating the tuberculous patients or of segregating them in special wards or apartments. With a view of preventing the spread of tuberculosis, the Board of Health of New York City has issued in English, Ger- man, Hebrew, and Italian the following circular for popular instruc- tion : — "Consumption is a disease which can be taken from others, and is not simply caused by colds. A cold may make it easier to take the disease. It is usually caused by germs which enter the body with the air breathed. The matter which consumptives cough or spit up con- tains these germs in great numbers; frequently millions are dis- charged in a single day. This matter, sj)it upon the floor, wall, or elsewhere, is aj)t to dry, become pulverized, and float in the air as dust. This dust contains the germs, and thus they enter the body with the air breathed. The breath of a consumptive does not contain the germs, and will not produce the disease. A well person catches the disease from a consumptive only by in some way taking the matter coughed up by the consumptive. "Consumption can often be cured if its nature is recognized early TUBERCULOSIS. 563 and proper means are taken for its treatment. In a majority of cases it is not a fatal disease. "It is not dangerous for other persons to live with a consumptive if the matter coughed up by the consumptive is at once destroyed. This matter should not be spit upon tlie floor, carpet, stove, wall, or street, or anywhere except into a cup kept for that purpose. The cup should contain water, so that the matter may not dry, and should be emptied into the closet at least twice a day, and carefully washed with hot water. Great care should be taken by a consumptive that his hands, face, and clothing do not become soiled with the matter coughed up. If they do become soiled, they should be at once washed with hot water and soap. When consumptives are away from home, the matter coughed up may be received on cloths, which should be at once burned on returning home. If handkerchiefs are used (worth- less cloths which can be burned are far better) , they should be boiled in water by themselves before being washed. "It is better for a consumptive to sleep alone, and his bed-cloth- ing and personal clothing should be boiled and washed separately from the clothing belonging to other people. "Whenever a person is thought to be suffering from consumption, the name and address should be sent at once to the health depart- ment, on a postal card, with a statement of this fact. A medical in- spector from the health department will then call and examine the person to see if he has consumption, providing he has no physician, and, if necessary, will give proper direction to prevent others from catching the disease. "Frequently a person suffering from consumption may not only do his usual work without giving the disease to others, but may also get well, if the matter coughed up is properly destroyed. "Eooms that have been occupied by consumptives should be thor- oughly cleaned, scrubbed, whitewashed, painted or papered before they are again occupied. Carpets, rugs, bedding, etc., from rooms which have been occupied by consumuptives, should be disinfected. The health department should be notified, when they will be sent for, dis- infecterl, and returned to the owner free of charge; or, if he so desire, they will be destroyed." In view of the possibility that patients convalescing from diph- theria may harbor the bacilli for some time after disappearance of clinical symptoms, it is advisable to maintain quarantine until two successive cultures show the absence of diphtheria bacilli from the thi'oat. 564 TEXT-BOOK OF HYGIENE. THE SANATORIUM TREATMENT OF TUBERCULOSIS. i\.s a restrictive measure against the spread of tuberculosis, the sanatorium treatment of the disease affords results which are hardly less gratifying than the curative effects of such treatment. This will be readily appreciated when it is remembered that every consumptive in his home is a possible and potential focus for the dissemination of the infection, and that when he is removed to a sanatorium there is one less center of infection to be dealt with. It has been demon- strated that under judicious and scientific administration the con- sumptive sanatorium does not become itself infected, and that the patients under the influence of a liberal dietary, life practically in the open air, regulated exercise and regular habits of life, improve or become actually cured in a percentage of cases which is very grati- fying, and affords strong grounds for hope in the gradual abolition of pulmonary tuberculosis. The results attained in the treatment of tuberculosis at the Fort Stanton Sanatorium, Fort Stanton, X. M., are thus summarized by Surgeon P. M. Carrington, who is in command of the station : — "1. Given a sufficient length of stay recovery may be e?cpected in a very large percentage in first stage uncomplicated cases. "2. Eecovery or arrest may be expected in a fair proportion of second and third stage cases and all the afebrile cases in which there remains sufficient sound lung tissue to support life, but we should exercise caution lest we be premature in pronouncing second and third stage cases cured. "3. Eesults in permanent febri'e cases, especially those in which there is a wide range of daily temperature, are not better than in less favorable climates. "4. Hemorrhages seem less liable at this altitude than at the sea-level. "5. Heredity plays an unimportant part in the causation of the disease." QUESTIONS TO CHAPTER XX. QUARANTINE. What is meant by quarantine? From what is the term derived? Has it now any definite limitation as to time? To what is the term applied? What are the two natural divisions of quarantine? What are the principal quarantinable diseases? What determines the length of quarantine for each of these? Should tuberculosis be quarantinable? What is meant by foreign quarantine? What regulations are now to be observed at foreign ports by vessels clearing for the United States? What oflncers have charge of this foreign quarantine ? What are some of the points considered in the bill of health? What are some of the requirements with regard to vessels and their cargoes? Regard- ing passengers and crew? What are the objects of the inspection card given to passengers? What requirements are to be observed at sea? What method is pre- scribed for the disinfection of vessels? Of cargoes? What can be said of the efficiency of the foregoing regulations? What is meant by domestic quarantine? What will govern the equip- ment of a maritime quarantine station? What are required at a fully- equipped station? What is the method of construction of the most recent steam disinfecting chambers, and in what ways are they superior to the earlier models? What precautions are to be observed in operating them? What is the principle of construction of the sulhpur-furnaces now used at quarantine stations, and wherein are they superior to other methods of producing sulphurous-acid? How is ths gas to be conveyed into the holds of vessels, etc.? What apparatus is provided for using germicidal solutions Where barracks are necessary, how should they be arranged and equipped? What facilities for bathing should be provided? What is to be said of the water-supply ? What regulations are to be observed at ports of entry and on the fron- tier? What points are covered by the inspection, and what vessels are exempt from inspection? What vessels are to be quarantined, and for how long? What are the general requirements at quarantine? What treatment must cholera-infected vessels undergo in quarantine? What is the prescribed method of disinfection ? What routine is to be observed with passengers detained on account of cholera? Under what conditions may traffic be allowed from ports infected with yellow fever? What inspection is required of State and local quarantines? What regulations govern the Canadian and Mexican frontiers? What are some of the points to be observed in the successful management of a quar- jintine station? (565) 666 TEXT-BOOK OF HYGIENE. What is the treatment required for cholera-infected vessels? What special measures are to be taken against cholera? Who has supreme com- mand of a cholera camp, and how is it to be divided? What are the regu- lations to be observed in the detention camp? In the hospital camp? Why should infected dejecta and ejecta be disinfected immediately upon discharge? How many national quarantine stations are there, and where are they located? Give a brief description of those in the Delaware Bay and River. What government vessel is used as a quarantine station? What are some of the aids to national quarantine? Wliat inspection is required of all quarantines? What is required of all State and local quar- antines? What are the instructions, both general and special, to the officers detailed to inspect State and local quarantines? What is meant by inland quarantine? By the sanitary cordon? When and where has the latter been employed in the United States, and with what success? What is a camp of probation? What is the difference between it and a camp of refuge? How should a camp of probation be equipped, man- aged, and guarded? What should be the daily roiitine of such a camp? What regulations should be promulgated and enforced for such a camp? Have these camps been efficacious ih preventing the spread of disease ? What is the purpose of railroad quarantine, and how is it to be carried out? How may it be facilitated by train-inspection service? What rules are to be adopted for railway quarantine? What action has been taken to pre- vent the introduction of small-pox, etc., from Canada? Wliat are the regula- tions issued for the guidance of sanitary inspectors? What provisions are there for the medical inspection of immigrants on board trains? What general principles govern interstate quarantine? What are the regulations covering it? Which of these is the most important? What spe- cial provisions are made respecting yellow fever ? What are the methods of disinfection prescribed, respectively, for cholera, yellow fever, small-pos, and typhus fever? Wliat are the essential points of municipal quarantine? What precau- tions are to be taken to prevent the spread of small-pox, measles, diphtheria, ai.d scarlet fever? To what extent should domiciliary quarantine be carried? How long should it be maintained? How may a diagnosis of diphtheria be made? What means may be taken to prevent the spread of tuberculosis? Give a synopsis of the quarantine laws of the United States. What is the maximum penalty for attempting to enter a port in evasion of them? What information of value to quarantine officers, etc., is furnished weekly? When and by whom may travel and traffic from infected ports and places be prohibited? Who has supreme charge of the enforcement of the quarantine regulations? In what aepartment of the government does the supervision of quarantine belong? INDEX. Abscesses, resume of, 437. Acclimatization to diminished air-pres- sure, 9. Actinomycosis, 434. resume of, 438. Acute Infectious diseases, propagation of, 7, 16. Adulteration of foods, 147, 148. Air, 1. See also Atmosphere, absorption of heat and aqueous vapor by, 4. ammonia in, 27. bacteria in, 6. bacteriological examination of, 31. quantitative, 33. carbon dioxide in, limit of, allowable, 38. carburetted hydrogen in, 27. -currents, sanitary relations of, 16. determination of organic matter in, 33. dry, in the causation of respiratory dis- eases, 14. dust in, 28. carrying bacteria, 28. in cities, 28. examination of, 29. for ammonia, 37. for bacteria, 31. for carbon dioxide, author's method, 34. Boom's method, 33. Pettenkofer's method, 35. for carbon monoxide, 37. for gases, 37. for organic matter, 33. for ozone, 30. Houzeau's test for, 30. for solid impurities, 30. Dixon's method, 30. for sulphur, 37. substances to determine in, 29. exhausting, from old wells and privy- vaults, 28. ground-, 161. impurities in respired, where found, 41. infection by contaminated, 7. -passages, diseases of, caused by low temperature, 13. -pressure, acclimatization to diminished. 9. effect of diminished, 8. purity of, in wells and privy-vaults, test for, 29. Air, questions to Chapter I on, 43. sanitary relations of changes in com- position and impurities of, 23. source of, for ventilation, 39. -space, dimensions of, per person, 39. initial, 39. Morin's table showing proper propor- tion of, 40. sulphuretted hydrogen in, 27. -tester, 34. warmth of, 4. wind caused by dififereuces in pressure of, 6. Ale, 143. Alcohol, abstainers and users of, table of expectation of life of, 141. amount of, in various medicines, 144. as a beverage, 143. ale, 143. beer, 143. brandy, 142. brown-stout, 143. forms of, 142. gin, 142. kumys, 143. porter, 143. whisky, 142. wine, 142. adulteration of foreign, 142. beverages containing, 138. "deadly parallel" between food and, 139. fatality of croupous pneumonia in users of, 141. influence of, upon the mortality from nervous diseases, table showing, 141. pathological effect of, 140. physiological effect of, 138. predisposition to disease in habitual users of, 141. therapeutic effect of, 138. Alimentary • overages, 138. Alkaloidal beverages. See Beverages, Alkaloidal. Altitude, atmospheric pressure in relation to, table showing, 3. high, effects of, 8. Alum, examination for, in bread, 155. Ammonia, albuminoid, in water, deter- mination of, 101. free, in water, determination of, 101. (567) 568 INDEX. Ammonia in air, 27. determination of, 37. in sewer-air, 27. in water, source of, 82. poisoning by, 250. Anchorages, 489. Aniline vapor, poisoning by, 257. Animals, diseases of, due to conditions of the soil, 169. Annatto, test for, 152. Anthrax, 435. resume of, 438. Antiseptics, disinfectants, and deodorants, 447. antiseptics, table of, 459. definitions of, 447, 448. deodorizers, 460. disinfectants for clothing, bedding, etc., 450. for excreta, 450. for furniture, etc., 451. ■ for merchandise and the mails, 451. for non-spore-containing matter, 449. for rags, 451. for railway cars, 452. for ships, 452. for spore-containing matter, 449. for the dead, 451. for the person, 451. for the sick-room and hospital wards, 451. formaldehyde, 456. and potassium permanganate, 457. danger of, 458. two classes of, 449. disinfection of clothing, 453. of excreta, 452. of ingesta, 455. of privy-vaults, cess-pools, etc., 455. of the person, 453. cf the sick-room, 454. questions on, 461. resistance of certain bacteria to, table of, 448. table of antiseptics, 459. Artesian wells, 61. Artificial sea-bath, recipe for ingredients of, 859. Asiatic cholera, history of, 409. Atmosphere, certain diseases communi- cable by, 7. See also Air. composition and physical conditions of, 2. effect of rarefied, on phthisis, 10. electrical and magnetic conditions of, 6. humidity of, connected with changes in health, 16. infection of, by coughing, sneezing, speaking, and exhaling, 7. influence of electrical conditions of, upon health, 17. Atmosphere, varieties of pathogenic bac- teria found in, 28. Atmospheric pressure, 3. causes of variations in, 3, 4. increased, 11. effects of, 11. influence of changes of, on health, 7. relation of humidity to, 4. relation of, to altitude, table showing, 3. Bacilli, typhoid, in ice, 54. Bacillus coli, effect of solutions of metals upon, 81. Bacteria in air, 6. examination for, 31. harmless, 7. pathogenic, 7. putrefactive, 7. role of dust in carrying, 7. in drinking-water. See Water, Drink- ing-, in sewer-air, 27. of non-putrefactive decomposition, 166. table showing resistance of certain, to disinfectants, 448. varieties of pathogenic, found in air, 28. Bactericidal action of metals, 81. Bacteriological examination of water, 105. Bacterium of non-putrefactive decomposi- tion, 166. of putrefaction, 366. Baker, H. B., observations on relation of respiratory diseases to low temperature, 13. Baking, broiling and, 137. Barometric pressure, effect of, 10. Barracks, 493. Bath-house, 493. Baths and bathing. See Personal Hygiene. Battlefield, interment on, 372. Beans, 134, 135. Beer, 143. Beverages, alimentary, 138. alkaloidal, 145. chocolate, 146. nutritive properties of, 146. coffee, 145. adulteration of, 146. artificial, 145. tea, 146. adulteration of, 146. containing alcohol, 138. See also Alco- hol. Bilge-water. See Marine Hygiene. Birth-rate and death-rate, 466. Births, registration of, 464. Bisulphide of carbon, poisoning by, 253. Boarding-station, 489. -vessel, 489. Boiling, 136. Bovine tuberculosis, 435. INDEX. 569 Brandy, 142. Bread. See Foods of Vegetable Origin. Broiling and baking, 137. Bromine and iodine vapors, poisoning by, 254. Brown-stout, 143. Building-site, 194. Burial grounds, supposed dangers of, 370. Butter. See Foods of Animal Origin. Caisson disease, 11. prevention of, 11. Calorie, 113. definition of, 113. Camp diseases, 279. hygiene, military and. See Military and Camp Hygiene. Camps, sanitary care of, 277. Candles, 203. Carbon bisulphide, poisoning by, 253. dioxide, determination of, 33. effects of, 24, 25. excess of, in water, effect of, on lead pipes, 78. in water, dangerous proportion of, 78. poisoning by, 252. proportion of, in the atmosphere, 38. allowable, 23, 24. monoxide, 26. poisoning by, 251. test for, 37. Carburetted hydrogen, "fire-damp," in the air, 27. poisoning by, 252. Carriers of infection, 387. Casualties and disabilities due to ship- wreck, 296. Cerebro-spinal meningitis, epidemic, his- tory of, 429. Cess-pools as sources of contamination, 50. disinfection of, 455. Cider, 143. Chalk strata in relation to hygiene, 196. Chart, acute lung diseases, 19. consumption, 18. cause of death of seafaring people, 292. diarrheal diseases, 20. diphtheria and croup, 22. diseases of seafaring people, 293. typhoid fever, 21. Cheese. See Foods of Animal Origin. Chimney as a ventilator, 41. Chlorine-gas, poisoning by, 251. Chocolate, 146. Choke-damp, 29, 252. poisoning by, 252. Cholera, Asiatic, history of, 409. epidemic of, at Hamburg, 85. in soldiers, 283. resum6 of, 438. Cholera, special measures against. See Quarantine. spirillum in water, 77. transmitted by drinking-water, 76. vessels. See Quarantine. Cisterns, above ground, 50. underground, 50. contamination of, 50. Clay, dense marls, and alluvial soils, 197. slate, the, 196. Climate and diarrheal diseases, 12. Clothing. See Personal Hygiene. disinfection of, 453. Coal-gas, composition of, 26. Coca, 146. Coffee, 145. ground, adulteration of, 146. Cold, respiratory diseases caused by, 13. Color of water, 100. significance of, 100. Construction of habitations, 192. of hospitals, 219. Contagion and infection, 385. carriers of infection, 387. differentation of, 385. incubation period of infectious diseases, table of, 386. period of infectiousness of patient, 387. questions on, 390. Cooking, 136. Copper and other metals, bactericidal ef- fect of, 81. Creamometer, 123, 124. Cremation. See Dead, Disposal of. Crematory, 494. Cultivated soils, 197. Cysticercus cellulosa in meat, 129. Danger from lead pipe as a conductor of water, 78. Dead, disposal of, 369. cremation, 371. entombment in vaults, 371. interment, 369. on the battlefield, 372. methods of, 369. questions on, 373. supposed dangers of burial grounds, 370. Death-rate among persons living in dif- ferent stories of houses, 193. among young children as a result of overcrowding, 194. and birth-rate, 466. relation of, to density of population, table on, 192. Deaths, registration of, 466. Decomposition, non-putrefactive, bacte- rium of, 166. Dengue, history of, 427. Deodorants, 447. 570 INDEX. Deodorization of contents of privies, 173. Deodorizers, 460. Dermatitis from sun's cays, 12. Diarrhea in soldiers, 279. Diarrheal diseases in the summer, 12. Diminished air-pressure, effect of, 8. Diphtheria, diagnosis of, 561. directions for making cultures in sus- pected cases of, 561. history of, 426. quarantine of, 559. resume of 438. Disease, diminution of, due to drainage of wet soil, 194. germ theory of, 374. questions on, 384. mosquito transmission of, management of epidemics of yellow fever in the light of, 542. Diseases, acute infectious, propagation of, 7, 16. camp, 279. contagious and infectious, Vacher's table of the time-periods of, 241. Whitelegge's table showing periods of quarantine after, 242. due to absorption or local action of irri- tating or poisonous sub- stances, 261. constrained attitude and sedentary life, 265. excessive use of certain organs, 263. exposure to elevated or variable tem- perature or atmospheric pressure, 263. exposure to mechanical violence, 265. impure drinking-water, 64. inhalation of irritating or poisonous dust, 258. gases or vapors, 250. epidemic, history of, 391. cerebro-spinal meningitis, epidemic, 429. cholera, Asiatic, 409. dengue, 427. diphtheria, 426. gonorrhea, 433. influenza, epidemic, 428. measles, 425. meningitis, cerebro-spinal, epidemic, 429. questions on, 442. relapsing fever, 419. scarlet fever, 425. small-pox, 396. inoculation, 399. vaccination, 401. Jcnner, Edward, 402. sweating sickness, 395. syphilis, 430. typhoid fever, 420. Diseases, epidemic, typhus fever, 421. yellow fever, 423. in hot climates, 12. in infants, 26. incident to school life, 235. infectious, resume of some of the, 437. abscesses, 437. actinomycosis, 438. anthrax, 438. cholera, 438. diphtheria, 438. dysentery, 438. glanders, 438. gonorrhea, 439. hydrophobia, 439. influenza, 439. leprosy, 439. malaria, 439. measles, 439. mumps, 439. parotitis, 439. pertussis, 441. plague, 439. pneumonia, 439. — rabies, 439. relapsing fever, 440. scarlet fever, 440. small-pox, 440. syphilis, 440. tetanus, 440. typhoid fever, 440. typhus, 440. tuberculosis, 440. whooping-cough, 441. yellow fever, 441. most frequent in prisons, 350. of animals communicable to man, 434. actinomycosis, 434. anthrax, 435. bovine tuberculosis, 435. glanders, 437. questions on, 446. rabies, 435. sheep-pock, 434. tuberculosis, bovine, 435. probably due to similar conditions of the soil, 169. quarantinable, 473. table of, 473. registration of, 465. spread by soil impurities, 116. Disinfectants. See Antiseptics, Disinfec- tants, and Deodorants. Disinfecting chambers, steam, 490. sulphur-furnace, 491. Disinfection by germicidal solutions, 492. of ships. See Marine Hygiene. Disposal of the dead. See Dead. Dixon's aeroscope, 30. Drains, best material for, 170. depth for, 170. INDEX. 571 Drains, trees for, 170, 198. Drainage, 170. of ships. See Marine Hygiene, -pipe, 170. Drinking-water, 62. See also Water, Drinliing-. contamination of, by excrement, 50. from ice and snow, 62. limit of solid matter allowable in, 63. sources of, 50. Dust, diseases due to inhalation of irri- tating or poisonous, 258. coal-dust, 258. metallic dust, 258. mineral dust, 258. vegetable dust, 259. in air, 28. carrying bacteria, 28. nature of, 31. occupations concerned in making, 249. Dwellings. See Habitations. Dysentery in soldiers, 279. resume of, 438. Earth-closet, 177. Effluvia from cemeteries and knackeries, 27. Eggs. See Foods of Animal Origin, from persons and discharges of sick in air, 38. Electric light, 204. Electrical and magnetic conditions of the atmosphere, 6. Epidemic cerebro-spinal meningitis, his- tory of, 429. diseases in hot climates, 12. influenza, history of, 428. Epidemics, typhoid, due to contaminated water-supply, 66-76. Erythema from sun's rays, 12. Eucalyptus tree for draining soil, 170, 198. Examination, bacteriological, of water. See Water, of food, 150. of water, 93. Excrement contaminating drinking-water, 50. Excreta, disinfection of, 152. Exercise and training. See Personal Hy- giene. Fat in milk. See Foods of Animal Origin. Fever, relapsing. See Relapsing Fever. scarlet. See Scarlet Fever. typhoid. See Typhoid Fever. typhus. See Typhus Fever. yellow. See Yellow Fever. Filters, comparative utility of slow sand and mechanical, 92. domeHtif, 81. mechanical, 90. Filters, mechanical, chemicals used with, 91. cleansing of, 91. efficiency of, 92. principles of, 90. slow sand, construction of, 84, 85. first in America, 88. Filtration, 81. conclusions of R. Koch upon, 86. Dr. A. Robin's conclusion from experi- ments at Wilmington, Del., 87-88. slow sand, 84. effect of, 84. general installation of, 88, 90. principles of, 84. summary of experiments upon, 87. table of comparative mortality before and after, 88, 89. Fire-damp, 252. dangers of, 252. in mines, 27. Flies, danger from, in quarantine, 526. Food, 110. adulteration of, 147, 148. adulterations of, table showing detection of, in one year in Illinois, 149. albuminoid proximate principles of, 117. caloric value of, to calculate, 115. calorie, 113. carbohydrates, 118. definition of, 110. dietaries, standard, Hutchison's, 114-115. dietary, for adult male of average weight, table of. 111. standards of, 111. examination of, 150. butter, 152. oleomargarine, 153. insoluble fatty acids, 154. melting-point, 154. specific gravity, 153. flour and bread, 154. for alum, 155. for copper sulphate, 155. for ergot, 155. for gluten in, 154. for mineral substances, 155. for water and ash, 154. milk, 150. for annatto, 152. for boric acid, 152. for cane-sugar, 152. for formaldehyde, 152. for percentage of ash, 151. for percentage of fats, 151. for sodium carbonate, 152. for total solids, 151. fat, 118. Increased combustion of, 118, 119. 572 INDEX. Food, greater consumption of carbohy- drates during exercise, 118. in prisons, 350. materials of average prices, table of comparative cost of digesti- ble nutrients and energy in different, 112. nutrition, physiology of. 111. nutritive ingredients of, table of, 116. principles, alimentary, 110. proximate, 110. proximate principles of, 110. quantity and character of, necessary, 110. fats or carbohydrates. 111. proteids. 111. salts, 110. water, 110. quantity of any single one necessary for existence, 117. questions to Chapter III on, 156. ration, an ideal, 115. reduced, of Chittenden, 115. of Chittenden, experiments with, 116. relation of climate to, 117. relative proportion of, for men and women, 11.3. of nitrogenous to non-nitrogenous, principles, 113. standard dietaries, Hutchison's, 114-115. unit of measurement of the fuel-value of, 113. uses of nutrients in body, 117. water and other inorganic proximate principles of, 118. Foods, classification of, 119. of animal origin, 119. adulteration of, 147, 148. butter, 120, 125. cheese, 125. relative value of different, in ali- mentary principles, 126. eggs, 133. cooked, digestibility of, 133. fish, oysters, crabs, and lobsters, poisoning by, 130. poisoning by, siguatera, 130. meat, 126. changes in, after death. 127. parasites in, 128. ptomaines in, 129. putrefaction of, 129. soluble preparations of, 127, 128. table of relative proportions of fat and proteids in, 127. tainted, prevention of disease from, 132. tuberculous, 131. unfit, 128, 129, 131, 132. prevention of disease from, 132. ptomaines in, 129. milk, 119. Foods, of animal origin, milk, adultera- tion of, 121. determination of the quality of, 123. infection by, 121, 122, 123. skim-milk, 121. specific gravity of, 124. tyrotoxicon in, 124. whey, 120. oleo-margarine, 125. "swill-milk," 123. of vegetable origin, 133. adulteration of, 147, 148. bread, 133. substitutes for, 134. condiments, 136. flour, adulteration of, 134. fruits and nuts, 135. green vegetables, 135. leguminous seeds, 134. composition of, 135. rye, disease due to, 134. Foodstuffs, caloric value of, 115. Formaldehyde as a disinfectant, 456. with potassium permanganate, 457. danger of, 458. Frost-bite, 13. Frying, 137. Fungi, lower, in air, 6. Gases from putrefaction, poisoning by, 253. or vapors, irritating or poisonous, dis- eases due to inhalation of, 250. ammonia, 250. aniline vapor, 257. bisulphide of carbon, 253. bromine vapor, 254. carbon bisulphide, 253. dioxide, 252. monoxide, 251. carburetted hydrogen, 252. choke-damp, 252. chlorine gas, 251. copper vapors, 256. fire-damp, 252. gases from putrefaction, 253. hydrochloric-acid gas, 250. hydrogen, carburetted, 252. sulphuretted, 253. iodine and bromine vapors, 254. lead poisoning, 254. mercurial poisoning, 255. methane, 252. nitric-acid fumes, 250. petroleum vapor, 254. sulphuretted hydrogen, 253. sulphurous-acid gas, 250. turpentine vapor, 254. zinc or copper vapors, 256. Gas-light, 204. Germicidal solutions, disinfection by, 492. INDEX. 573 Gin, 142. Glanders, 437. resume of, 438. Gonorrhea, history of, 433. resume of, 439. Granitic, metamorphic, and trap rocks, the, 195. Gravels, 196. Ground-air. See Soil, Atmosphere of. -water. See Water, Ground-. Guarana, 146. Gymnastic training, tables showing effects of, on development, 355, 357. Habitations, construction of, 192. character of the soil, 195. chalk, 196. clay, dense marls, and alluvial soils, 197. clay slate, 196. cultivated soils, 197. granitic, metamorphic, and trap rocks, 195. gravels, 196. limestone and magnesium limestone rocks, 196. sands, 196. sandstones, 196. house-drainage, 205. water-closets, 206. house-drain, 215. soil pipe, 214. traps, 212. water-supply for, 211. interior arrangements, 196, 200. size of rooms, ventilating and heat- ing, 200. wall-coating, 203. lighting, 203. materials, 198. questions on, 217. site, 194. unsanitary, effects of, upon young children, 194. water-supply, 205. ofBcial supervision of the sanitary ar- rangements of, 216. Hardness of water. See Water. Health and life, relation of occupations to, 246. effect of changes of temperature on, 11, 12. prevention of, 12. of continual inhalation of sewer-a:r upon, 27. humidity of atmosphere connected with changes of, 16. Influence of changes of atmospheric pressure on, 7. occupations prejudicial to, 249. Heat, eflcfts of great, 203. History of epidemic diseases. See Dis- eases, Epidemic, History of. marine hygiene, 285. Hospital, general, administration and management of, 226. Hospitals, construction of, 219. administration building, 226. buildings, 219. bathrooms, 224. dead-house, 225. dining-room, 225. disinfecting chest, 225. fireproof material in ceilings, 224. floors, 223. Johns Hopkins Hospital as a model, 220, 221. kitchen, 225. laundry, 226. pavilion system, 220. questions on, 228. site, 219. ventilation and heating, 222. ward-kitchens, 225. water-closets, 224. water-supply, 225. House, material for building, 198. Houses. See Habitations. Humidity, absolute, 5. low absolute, a cause of respiratory dis- eases, 13. of atmosphere connected with changes of health, 16. relation of, to atmospheric pressure, 4. to temperature, table showing, 5. Hydrants, out-door, 78. Hydrochloric acid gas, poisoning by, 250. Hydrogen, carburetted, in the air, 27. poisoning by, 252. Hydrogen, sulphuretted, in the air, 27. poisoning by, 253. Hydrophobia. See Rabies. Hygiene, industrial, 246. marine. See Marine Hygiene, military and camp. See Military and Camp Hygiene, personal. See Personal Hygiene, prison. See Prison Hygiene, school. See School Hygiene. Ice, 53. contaminated, 54. snow, 54. Illuminating gas, carbon monoxide in, 26. chronic poisoning with, 26. Immunity, theories of, 379. Ehrlich's, '"2. Mctchnikoff's, 381. questions on, 384. Impurities in water, 63. soil, diseases spread by, 116. Industrial hygiene, 246. 574 INDEX. Industrial hygiene, questions on, 266. Infection by contaminated air, 7. carriers of, 387. Influenza, epidemic, history of, 428. resume of, 439. Ingesta, disinfection of, 455. Interment. See Dead, Disposal of. Iodine and bromine vapors, poisoning by, 254. Kefyr, 143, 144. Kerosene, 203. Kumys, 143, 144. Lactodensimeter, 124. Lactometer, 123. Lactoscope, 123. Lead pipes as conductors of water, dan- gers of, 78. poisoning, 254. Legumes, 134, 135. Lentils, 134, 135. Lepr resume of, 439. Life and health, relation of occupations to, 246. expectation of, in abstainers and users of alcohol, table of, 141. Lighting, 203. Limestone and magnesium limestone rocks, the, 196. Malaria, resume of, 439. Malarial fevers in soldiers, 280. Man, diseases of animals communicable to. See Diseases. Marine hygiene, 285. bilge, composition of, 307. tables of, 308. -■water, of the boiler-room, 311. of the cambuse, 311. of the engine-room, 311. of the store-room, 311. drainage of ships, 297. battleships, 297. bilge-water, 297. tables of variation of composition of 307, 309, 310. summary, 301. surface drainage, 300. two methods of, 297. historical, 285. morbidity and mortality occurring in seafaring people, 288. casualties and disabilities due to shipwreck, 296. tables of, 296, 297. charts of, 292, 293. health of the navy and marine corps of the United States, 290. tables of, 290, 291, 294, 295. Marine hygiene, navy ration, 325. tables of, 328, 329, 330, 331, 332. questions on, 347. ship, the, 312. cleanliness, 318. dry decks, 319. table showing benefit of, 319. construction, 312. battleship, air-space of, table of, 318. plan of, 315. disinfection, 320. carbon dioxide, 325. formaldehyde, 323. lime, 324 mercuric chloride, 324. steam, 323. sulphur, 322. ventilation, 338. different methods of, 340. systems of Idaho and Mississippi, 342. tables of, 345, 346. water-supply, 332. allowance of, per man, 336. analysis of, table showing, 335. contamination of, 336. distilled, table of, 335. distillers, 332. scuttle-butt, 337. Marriages, registration of, 465. Mate, 146. Measles, history of, 425. quarantine of, 558. resume of, 439. Meat. See Foods of Animal Origin. Mechanical filters. See Filters. Meningitis, cerebro-spinal, epidemic, his- tory of, 429. Mercurial poisoning, 255. Methane, poisoning by, 252. Methods of purification of sewage, 186. See Sewage, Methods of Purifi- cation. Micro-organisms in sewer-air, 28. Military and camp hygiene, 268. camp diseases, 279. cholera, 283. diarrhea, 279. dysentery, 279. malarial fevers, 280. phthisis, 283. scurvy, 283. typhoid fever, 282. typhus fever, 283. venereal diseases, 283. yellow fever, 282. hospital tents, 276. mosquitoes, 281. questions on, 284. INDEX. 575 Military and camp hygiene, sanitary care of camps, 277. the clothing of the soldier, 272. the dwelling of the soldier, 274. tents, 276. the food of the soldier, 270. table showing components of, 270- 271. table showing calories of (German army), 271. the recruit, 268. the training of the soldier, 269. Milk. See Foods of Animal Origin. Mineral waters in this country, classifica- tion of, 55. table showing analyses of some of the more popular, 60. Mines, fire-damp in, 27. Model study room, 232. Moore, J. M., observations on relation of respiratory diseases to low temperature, 14. Morln's table for air-space, 40. Mortality among residents of badly con- structed dwellings, 192. from typhoid fever, table of, 90. from various diseases, table showing in- fluence of alcohol upon, 141. table of comparative, before and after filtration, 88, 89. typhoid, average, in cities supplied with filtered water, 76. in American cities, table showing, 72- 75. Mosquito, danger from, in quarantine, 526. influence of, upon the management of yellow fever, 541. transmission of disease, management of epidemics of yellow fever, in the light of, 542. Mosquitoes and camp-life, 281. Moulds in air, 6. spores of, In air, 6. Mountain sickness, 9. Mumps, resume of, 439. Municipal quarantine. See Quarantine. National quarantine. See Quarantine. Naval hygiene. See Marine Hygiene. Nervous disorders in school-children, 239. Nitrates and nitrites in water. See Water. Nitric-acid fumes in factories, 250. Nitrogen in atmospheric air, 2. Occupation neuroses, 264. Occu(pations concerned in making dust, 249. hygiene of. See Industrial Hygiene. prejudicial to health, 249. Occupations, relation of, to health and life, 246. table showing average age of certain, 247. Odor of water, 101. significance of, 101. Oleo-margarine. See Foods of Animal Origin, Butter. Organic matter in water. See Water. Overcrowding in cities, 192, 193. relation of, to pulmonary tuberculosis, 193. Oxygen and carbon dioxide in ground-air. See Soil, Atmosphere of. Oxygen in atmospheric air, 2. Ozone in atmosphere, 6, 30. test for, 30. Paraguay tea, 146. Parasites in meat, 128. cysticercus cellulosa, 129. trichina spiralis, 128. Parkes and Kenwood's table of daily quan- tity of water required by human beings, 47. Parkes's rules for ventilation, 41. Parotitis, resume of, 439. Patent medicines, amount of alcohol in various, 144. Peas, 134, 135. Pellagra, 134. Perflation, 40. Person, disinfection of, 453. Personal hygiene, 353. baths and bathing, 357. cold, 358. taken when heated or perspiring, 359. cramps, 360. drowning, methods of resuscitation for, 360. Michigan, 361. Sylvester's, 360. free, 362. questions on, 367. rules for, 359. sea-bathing, 358. artificial, recipe for, 359. tepid, warm, or hot, 358. clothing, 363. absorption of gases and vapors by, 365. color, 364. dyes, 365. fit, 365. materials for, 363. animal skins, 364. cotton, 363. leather, 364. 576 INDEX. Personal hygiene, clothing, materials for, linen, 363. silk, 364. ■wool, 363. non-inflammable, process of render- ing, 365. questions on, 368. exercise and training, 353. amount required, 356. overexertion, 356. questions on, 367. tables showing effect of gymnastic training on development, 355, 357. questions on, 367. recreation and rest, 366. Petroleum vapor, effects of, 254. Pettenkofer's method for determining car- bon dioxide in air, 35. Phthisis, effect of rarefied atmosphere on, 10. in soldiers, 283. Pioscope, 123. Plague, oriental, history of, 391. resume of, 439. -vessels. See Quarantine. Flans of intake and wattr-tower in Wil- mington. Del., 83. of slow sand filters, 85. of storage reservoir in Wilmington, Del., 82. Pneumonia, croupous, fatality of, in users of alcohol, 141. resume of, 439. Poisoning by absorption or local action of irritating or poisonous sub- stances. See Poisonous Sub- stances, by inhalation of gases or vapors. See Gases, etc. chronic, with illuminating gas, 26. Poisonous dust, diseases due to the in- halation of irritating or, 258. gases or vapors, diseases due to the inhalation of irritating or, 250. substances, diseases due to the absorp- tion or local action of irri- tating or, 261. alkali, strong. 262. arsenic, 261. bichromate of potassium, 262. glass-blowers, 262. petroleum, 262. phosphorus, 261. potassium bichromate, 262. quinine, 262. Population, density of, table on relation of death-rate to, 192. Porter, 143. Principles, alimentary, 110. See Food. Proximate, 110. See Food. Prison hygiene, 348. diseases most frequent in prisons, 350. exercise, 350. food, 350. punishment, 350. questions on, 352. reform, principles of, 348. site for, qualities necessary, 350. Privies as sources of contamination, 50. ventilation of, 173. Privy-vaults, disinfection of, 455. Ptomaines in meat, 129. Prophylaxis against yellow fever on the Texas-Mexican border, cam- paign of, 543. Proteids. See Foods. Proximate principles, 110. See Food. Pulmonary affections, chronic, conditions predisposing to, 25. tuberculosis and overcrowding, 193. Purification of water, storage and, 77. Putrefaction, bacterium of, IfiO. definition of, 369. gases from, poisoning by, 253. Quarantinable diseases, 473. table of, 473. Quarantine, 472. definition cf, 472. diseases, quarantinable, 473. table of, 473. division of, two natural, 473. domestic, 488. plant for, 489. anchorages, 489. barracks, 493. bath-house, 493. boarding-station, 489. boarding-vessel, 489. crematory, 494. disinfection by germicidal solutions, 492. by steam-chambers, 490. by sulphur-furnace, 491. hospitals, 492. steam disinfecting chambers, 490. sulphur-furnace, 491. water-supply, 494. wharves, 489. regulations, 495. disinfectants, authorized and meth- ods of use, 508. application of, in quarantine work, 512. INDEX. 577 Quarantine, domestic regulations, applica- tion of disinfectants, vessel, articles injured by steam, 513. bedclothes, 513. clothes and room furnishing, 513. cooking and eating utensils, 514. hold of, iron, 512. holds of, 513. living apartments, 513. textiles, soiled, 514. gaseous, 509. formaldehyde gas, 510. sulphur dioxide, 509. physical, 508. boiling, 508. burning, 508. steam, 509. solutions, chemical, bichloride of mercury, 512. carbolic acid, 512. formalin, 512. Infection, 495. of State and local, 508, 530. preamble, 495. quarantine, 497. requirements, general, 498. special, Canadian and Mexican frontiers, 506. on account of cholera, 500. leprosy, 504. plague, 505. small-pox, 503. typhus fever, 504. yellow fever, 501. relating to naval vessels, 507. stations, maritime, 488. flies, danger from, in, 526. foreign, 473. regulations, 474. bills of health, 474, 477. exemptions, 477. form of, 474-475. supplemental, 475, 477. form of, 475-476. cargo, 479. exemptions, 480. efficiency of, 486. inspection of vessels, 478. passengers and crew, 481. inspection card, form of, 483. ports exempted on Canadian border, 477. quarantinable diseases, 474. records, reports, etc., 484. requirements at sea, 484. disinfecting solutions, 486. | 37 Quarantine, foreign regulations, require- ments at sea, with regard to vessels, 478. inland, 533. camps of probation, 536. Camp Perry, Fla., 537. discipline of, 5.38. detention camp, Waynesville, Ga., 539. cordon, the sanitary, 533. yellow fever, in Texas, 534. interstate, 551. notification, 552. quarantinable diseases, 552. regulations, general, 552. disinfection, 554. for cholera, 554. for small-pox, 555. for typhus fever, 556. for yellow fever, 554. yellow fever, 553. mosquito, danger from, in, 526. influence of, upon the management of yellow fever, 541. transmission of yellow fever, manage- ment of epidemics in the light of, 542. municipal, 556. diphtheria, 559. diagnosis of, 561. directions for making cultures in suspected cases of, 561. measles, 558. scarlet fever, 559. tuberculosis, 562. sanatorium treatment of, 564. plant, quarantine, 489. questions on, 565. railroad, and inspection service, 544. medical inspection of immigrants, 550. regulations for sanitary inspectors of, 548. train-inspection service during the Brunswick epidemic, 545. school, 242. service, the national, 527. aids to, 529. stations on Delaware Bay and River, 327. station, management of, 514. cholera, special measure against, 521. camip, regulations for, 524. detention, 524. hospital, 525. inspection, 514. vessels, cholera, treatment of, 519. plague, treatment of, 517. yellow fever, treatment of, 515. stations, maritime, 488. 678 INDEX. Quarantine, yellow fever, campaign of prophylaxis against, of the Texas-Mexican border, 543. Influence of the mosquito upon the management of, 541. management of epidemics of, in the light of the mosquito trans- mission of, 542. Quarantines, national inspection of all, 508, 530. Instructions to officers making, 530. general, 531. special, 531. Questions to Chapter I, air, 43. to Chapter II, water, 107. to Chapter III, food, 156. to Chapter IV, the soil, 170. to Chapter V, removal of sewage, 190. to Chapter VI, construction of habita- tions, 217. • to Chapter VII, construction of hospitals, 228. to Chapter VIII, school hygiene, 244. to Chapter IX, industrial hygiene, 266. to Chapter X, military and camp hygiene, 284. to Chapter XI, marine hygiene, 347. to Chapter XII, prison hygiene, 352. to Chapter XIII, personal hygiene, 367. to Chapter XIV, disposal of the dead, 373. to Chapter XV, the germ theory of dis- ease, 384. to Chapter XVI, contagion and infection, 390. to Chapter XVII, history of epidemic diseases, 442. to Chapter XVIII, antiseptics, disinfec- tants and deodorants, 461. to Chapter XIX, vital statistics, 470. to Chapter XX, quarantine, 565. Rabies, 435. resume of, 439. Ragsorters' disease, 260. Rain-water. See Water. Ration, navy, 325. tables of, 328, 329, 330, 331, 332. Recreation and rest. See Personal Hy- giene. Registration of births, 464. deaths, 466. diseases, 456. marriages, 465. Regulations, quarantine. See Quarantine. Relapsing fever, history of, 419. resume of, 440. Removal of sewage, 172. See Sewage. Respiratory diseases, relation of cold to etiology, of, 13. Respiratory organs, certain diseases com- municable by, 7. Restoration of apparently drowned per- sons, 360. River-water. See Water. Roasting, 137. Rum, 142. Sands, 197. Sandstones, 196. Sanitary care of camps, 277. Scarlet fever, history of, 425. quarantine of, 559. resume of, 440. School hygiene, 229. age to start in school, 235. blackboards, 234. deskS; 233. ^ gymnastic exercises, 235. height of schools, 230. length of time in school, 235. lighting of schools, 232. model study room, 232. questions on, 244. ventilation, 229, 230. water-closets, 233. -life, diseases incident to, 235. causes of pulmonary tuberculosis, 240. communicable, 240. defective hearing, 238. digestive derangements, 240. disordered menstruation, 240. near-sightedness, 236. nervous, 239, 240. spinal curvature, 23S. Sea-bath, artificial, recipe for, 359. Sedentary life, diseases due to, 265. Septic tank method of removal of sewage, 186. Sewage, changes taking place in, table of, 185. deodorization of, 173. disposal of, 184. methods of purification of, 186. bacterial, 186. broad irrigation, 186. irrigation with copious underdrain- age, 186. sedimentation and irrigation, 186. "septic tank," 186. sterilization by heat, 186. more important bacteria found in, 185. purification of, a biological process, 184. removal of, 172. eartn and ash-closets, 177. -closet, comparison of, with water- closet, 179. midden system, 174. questions to Chapter V on, 190. pit system, 174. INDEX. 579 Sewage, removal of, pneumatic system of Liernur, 179. privy and privy-well system, 173. -well system, 174. reasons for, 172. Rochdale, or pail-closet, system, 175. systems of, 173. water-carriage systems, 180. "combined," 180. "separate," 180, 181. total quantity of, for each individual, 172. Sewer-air, 27. ammonia in, 27. bacteria in, 27. composition of, 27. Sewer-pipe, 170. Sheep-pock, 434. Ships. See Marine Hygiene. Shipwreck, casualties and disabilities due to, 296. tables of, 296, 297. Sick-room, disinfection of, 454. Siguatera, 130. Site for prisons, qualities necessary, 350. Small-pox, history of, 396. See Diseases, Epidemic, History of. quarantine of, 503. resume of, 440. Snow-blindness, 13. prevention of, 13. -water, 50. Soil, atmosphere of, 161. contamination of, with sewage, 172. in relation to diseases, 162. micro-organisms in, 163. movements of, 163. oxygen and carbon dioxide in, 161. significance of carbon dioxide in, 164. character of, 195. physical and chemical, 160. in relation to construction of habita- tions, 195. conditions of, diseases of animals due to, 169. drainage of, 170. drains, best material for, 170. eucalyptus tree for, 170, 198. sewer-pipe, 170. sunflower-plants for, 170, 198. impurities, diseases spread by, 166. Questions to Chapter IV on, 170. water of, 165. wet, diminution of disease due to, table of, 194. drainage of, prophylactic against pul- monary tuberculosis, 194. predisposing to pulmonary tubercu- lo.sis, 194. fianltary results of drainage of, 194. drains, drainage-pipe, 170. Soldier, clothing of, 272. dwelling of, 274. food of, 270. infectious diseases of, 279. yellow fever, 282. typhoid fever, 282. malarial fever, 280. cholera, 283. diarrhea, 279. phthisis, 283. dysentery, 279. venereal diseases, 283. training of, 269. Solids, total, in water, determination of, 101. Sources of drinking-water, 50. Solutions, germicidal, disinfection by, 492. Spring-water, 54. Statistics, vital. See Vital Statistics. Steam disinfecting chambers, 490. Still-births among upper-story dwellers, 193. Storage and purification of water, 77. reservoir in Wilmington, Del., plans of, 82. Suicide by inhaling fumes of charcoal, 26. relation of, to seasons, 23. Sulphuretted hydrogen, in the air, 27. Sulphur-furnace 491. Sulphurous-acid gas, poisoning by, 250. Sun's rays, dermatitis from, 12. direct influence of, 12. erythema from, 12. Sun-stroke, 12, 263. conditions predisposing to, 12. prevention of, 12. Sweating sickness, history of, 395. Syphilis, history of, 430. resume of, 440. Table of antiseptics, 459. of changes taking place in sewage, 185, 186. of comparative cost of digestible nu- trients and energy in dif- ferent food materials of average prices, 112. of deaths from typhoid fever, 90. of dietary for adult male of average weight, HI. of food adulterations for one year in Illinois, 149. of mineral waters in this country, 55. of quarantinable diseases, 473. of standard dietaries, Hutchison's, 114- 115. of the time-periods of contagious and infectious diseases, Vach- er's, 241. showing analyses of artesian well water, 62. 580 INDEX. Table showing analyses of bilge-water in warships, 309, 310. analyses of some of the more popular mineral waters, 60. analyses of water-supply of warships, 335. average age-limit in certain occupa- tions, 247, 24S. benefits of dry deck cleaning, 319. casualties of seafaring people, 296, 297. characteristics of waters according to de Chaumont's classifica- tion, 99. comparative expectation of life iu abstainers and non-abstain- ers, 141. comparative mortality before and after filtration, 88, 89. comparison of carbon dioxide and ni- trogen excretion of a man at rest and at work, 118. components of the United States Army's rations, 270-271. composition of bilge, 308. composition of kumys, cows' milk kumys, and kefyr, 144. composition of legumes, 135. cubic air-space on warships, 318. daily composition of water in Ameri- can cities, 47-49. daily quantity of water required by human beings, 47. effects of gymnastic training on de- velopment, 355, 357. incubation period of infectious dis- eases, 386. influence of alcohol upon the mortality from various diseases, 141. morbidity and mortality of seafaring people, 290, 291, 294, 295. navy rations, 328, 329, 330, 331, 332. nutritive ingredients of food, 116. percentage of alcohol in patent medi- cines, 144. periods of quarantine after contagious diseases, Whitelegge's, 242. proper proportion of air, 40. relation of atmospheric pressure to altitude, 3. relation of death-rate to density of population, 192. relation of humidity to temperature, 5. relative number of bacteria found in series of wells, 61. relative proportions of fat and proteids in meat, 127. relative value of different kinds of cheese in alimentary princi- ples, 126. Table showing resistance of certain bac- teria to disinfectants, 448. the sanitary result of drainage of wet soil, 194. typhoid mortality in American cities, 72-75. uses of nutrients in the body, 117. variations in composition of bilge- water, 307. ventilation of warships, 345, 346. Tape-worms, ova of, in water, 63. Tea, 146. Temperature, diseases due to exposure to elevated or variable, 263. effect of changes of, on health, 11. effect of, 11, 12. effect of, prevention of, 12. low, effects of, 13. relation of humidity to, table showing, 5. Tents, hospital, 276. Tobacco, 146. -amaurosis, 146. effects of, 146. Tetanus, resume of, 440. Trichina spiralis in meat, 128. Tuberculosis, bovine, 435. in soldiers, 282. pulmonary, predisposing causes of, 240. relation of overcrowding to, 193. wet soil, drainage of, as a prophy- lactic, 194. predisposing to, 194. quarantine of, 562. resume of, 440. sanatorium treatment of, 564. Tuberculous meat, 131. Turpentine vapors, effects of, 254. Typhoid bacilli in ice, 54. fever, epidemics of, due to contaminated water-supply, 66-76. epidemics of, water-borne, 96, 97. history of, 420. in soldiers, 282. mortality average in cities supplied with filtered water, 76. in American cities, table showing, 72- 75. table of deaths from, 90. Typhus fever, resume of, 440. history of, 421. Tyrotoxicon in milk, 124. Vaccination, 401. and syphilis, 407. moae of performing the operation, 404. symptoms, 403. Vacher's table of the time-periods of con- tagious and infectious dis- eases, 241. INDEX. 581 Vaults, entombment in, 371. Vegetable foods, 135. Venereal diseases in soldiers, 283. Ventilation, 200. and heating, 200. artificial, 40. definition of, 38. how accomplished, 40. natural, 40. of hospitals, 222. of privies, 173. of schools, 230. of ships, 338. See Marine Hygiene. Parkes's rules for, 41. principles of, 38. proper system of, 39. questions on, 45. source of air for, 39. Ventilators, 200-201. Vessels, cholera. See Quarantine, plague. See Quarantine, yellow fever. See Quarantine. Violence, diseases due to exposure to mechanical, 265. Vital statistics, 462. death-rate and birth-rate, 466. questions on, 470. registration of births, 464. of deaths, 466. of diseases, 465. of marriages, 465. Wall-coating, 203. "Water, 46. albuminoid ammonia in, 95. ammonia in, from cattle-manure, 52. source of, 96. bacteriological examination of, 97, 105. media for, 105. procedure, 105. bilge-. See Marine Hygiene, carbon dioxide in, dangerous proportion of, 78. effect of, on lead pipes, 78. excess of, effect of, on lead pipes, 78. chemical analysis of, object of, 94. objections to, 96. ohlorides in, 95. classification of, de Chaumont's, 98. table of characteristics of, 99. clear but containing disease germs, 96. -closets, 206. water-supply for, 211. color of, 63. daily consumption of, in American cities, table of, 47. daily quantity of, required by human beings, table of, 47. deep well, ammonia in, source of, 96. nitrites in, source of, 96. drinking-, 62. Water-drinking, bacteria in, safe limit of, 98. cholera transmitted by, 76. contamination of, by excrement, 50. diseases due to impure, 64. cretinism, 64. diarrhea, 65. dysentery, 65. parasitic, 66. typhoid, 66. limit of solid matter allOTT-abl? in, 63. sources of, 50. examination of, 93, 100. albuminoid ammonia, 101. chlorine, 103. significance of, 103. color, 100. significance of, 100. for lead, copper, and iron, 104. free ammonia, 101. hardness, 104. nitrates, 102. significance of, 102. rtrites, 101. odor, 101. significance of 101. organic nitrogen, 101. oxygen consumed, 102. significance of, 103. for phosphates, 105. total solids in, 101. turbidity, 100. significance of, 100. filtered, average typhoid mortality in cities supplied with, 76. freezing, 53. from fresh-water lakes and ponds, 53. fungi and algee in, 53. ground-, 165. contamination of, with sewage, 172. influence of, on bacteria of decomposi- tion, 166. on bacteria of putrefaction, 167. micro-organisms in, 166. hard 64. hardness of, 63. cause of, 64. determination of, 64, 104. permanent. Pi. soap test for, 64. temporary, 64. toial, 64. impurities in, 63. mineral, in this country, classification of, 55. table showing analyses of some of the more popular, 60. nitrates and nitrites in, 95. source of, 96. nitrites and nitrates in, 95. objectionable organic impurities in, 94. 582 INDEX. Water, organic matter in, 65. nitrogen in, 95. ova of tape-worm in, 63. petroleum in, 63. potable, qualities of good, 62. proportion in tissues of animal body, 46. purification of, by alum, 64, 79. by boiling, 78. by bromine, 79. by copper sulphate, 79. by ferrous sulphate and lime, 64. Lind's method, 78. by ozone, 93. by potassium permanganate, 79. quantity of, required by human beings, 46. questions to Chapter II on, 107. rain-, 50. qualities of, 51. result of decomposition of organic im- purities in, 94. table of, 95. :.'iver-, 51. objections to, 51. self-purification of, 52. salts in, 95. sediment in, 63. examination of, 63. snow-, 50. spring-, 54. storage and purification of, 77. by sedimentation, 81. filtration, 81. Impurities from containers, lead pipes, 78. sulphur in, 63. Water-supply, 494. for hospitals, 225. of ships. See Marine Hygiene, transparency of, 63. well, 61. artesian, analyses of, 62. quantity, 62. bacteria in, 61. Weather, influence on the causation of dis- ease and mortality, 17. Wells, artesian, 61. mineral contents of, 62. deep, 61. Wind, 6. dry, 6. moist, 6. Winds, mistral, bora, northers, sirocco, harmattan, simoon, fohn, 16-17. Wine, 142. adulteration of foreign, 142. Wharves, 489. Whisky, 142. Whitelegge's table showing periods of quarantine after contagious diseases, 242. Whooping cough, resume of, 441. Wool-sorters' disease, 260. Yeasts in air, 6. Yellow fever, history of, 423. in soldiers, 282. resume of, 441. vessels. See Quarantine. Zinc or copper vapors, poisoning by, 256. RA425 Rohe R63 1908