4V- /> / m£ ^lM&^ e w ^ Columbia ©ntbersitp in tfte Cttp of iSeto gorfe LIBRARY Digitized by the Internet Archive in 2011 with funding from Open Knowledge Commons http://www.archive.org/details/inauguraldissertOOirvi A N INAUGURAL DISSERTATION ON THE INFLUENZA. SUBMITTED TO THE PUBLIC EXAMINATION OF THE FACULTY OF PHYSIC, UNDER THE AUTHORITY OF THE TRUSTEES OF COLUMBIA COLLEGE, IN THE STATE OF NEW-YORK, WILLIAM SAMUEL JOHNSON, LL. D. Prefident; FOR THE DEGREE OF DOCTOR OF PHYSIC, ON THE SIXTH DAY OF MAY, 1794. By PETER IRVING, Citizen of the State of New- York. Maxima pars hominum morbo ja&atur eodem. Horacj NEW-YORK: Printed by T. and J. Swords, Printers to the Faculty of Phyfic of Columbia College, No. 167, William-Street. \JnLj-t CX5 T O His Excel. GEORGE CLINTON, Governor of the State of New- York ; Whofe long and faithful Services to his Country, Whofe ileady Attachment to the Caufe of Liberty, AND, Whofe Virtues as an Individual rauft endear him to every American ; THIS DISSERTATION Is infctibedj With the warmed Sentiments of Refpe£i and Efteem, By his mofl obedient Servant, The AUTHOR. T O JOHN BROOME, Prefident, AND ISAAC STOUGHTENBURGH, JOHN CAMPBELL, THEOPHILUS BEEKMAN, GABRIEL FURMAN, GEORGE JANEWAY, NICHOLAS CARMER, FREDERICK STYMETS, ROBERT BOWNE, WHITE MATLACK, NATHANIEL HAZARD, ROBERT LENOX, Dr. MALACHI TREAT, Dr. SAMUEL BARD, Who compofe the Committee of Health. Gentlemen, t HE firm and determined manner in which you executed the arduous truft lately confided to you, and the fervice you have rendered the community by, in all probability, preferving this city from the dreadful calamity with which a neighbouring one was fo lately afflicted, deferve the grateful acknowledgements of your ( 6 ) your fellow-citizens: while your humanity, in tem- pering neceffary ftridtnefs with companion, and pre- fenting the mod timely and effential afliftance to the difconfolate fufFerers, enfure you their efteem. Emboldened by the numerous marks of politenefs and attention which I received while ferving under your direction, I have taken the liberty of foliciting a renewal of your patronage, and of addreffing to you this trifling production, which will need all your candour and all your indulgence. It is with pleafure that I confers myfelf under pecu- liar obligations to one member of your refpedtable body— Dr. Malachi Treat ; not only for the in- formation I have received from him in the fcience of medicine, but alfo for the many teftimonies of his friendfhip which I have repeatedly experienced. To merit, gentlemen, a continuance of your ap- probation, will ever be my higheft wifli. I am, With the greateft refpeel:, Your much obliged fervant, The AUTHOR. PREFACE. PREFACE. HE difficulties under which a young man labors, who writes for public inspection, are numerous and difcouraging ; but the Medical Graduate is furrounded by peculiar difad vantages. Having as yet formed none but undigefted opinions, the remit of a flight, and, at beft, but fuperficial knowledge of medicine; opinions of which a few years increafe of information may perhaps render him afhamed \ he is obliged to expofe them to the view of the public, who pof- fefs no other criterion by which to judge of his abilities. Agreeably, however, to the regulations of the Univerfity, I here fubmit to the perufal of my fellow-citizens the hafty production of a very few days \ trusting that, when all circumftances are confidered, it will be received with indulgence. DISSERTATION ON THE INFLUENZA, I .T is an old and well eftablifTied adage, that cuftom reconciles all things. The univerfal prevalence of evil has long fince habituated the world to its uncom- fortable effects. Difeafe itfelf, though always an un- welcome vifitor, has become an old acquaintance; and thofe complaints, not generally fatal, which are moft common, are at length fo familiarifed to our ideas by the frequency of their occurrence, that while abfent, they are rarely dreaded, and when felt, are commonly difregarded. Among difeafes of this defcription, to which we are moft accuftomed, may catarrh be reckoned; and as it not unfrequently lays the foundation of diforders of a more ferious and alarming nature, it merits the B ftri6bft ( io ) ftridleil attention, notwithstanding the neglect it too often, and indeed almoft always receives. From the flighted view of the caufes which induce catarrh, it appears evident, that it has not lately commenced its exiftence, but that mankind have ever been fubjecT: to its evils, fince they were firft expofed to viciflkudes of cold and heat. Syftematic writers have divided it into two fpecies. ,r. The ordinary catarrh, or common cold. 2. The contagious catarrh, commonly known by the term Influenza. To the consideration of the latter I mean at prefent to confine myfelf. The influenza extends over vaft tracts of country, and univerfally attacks the inhabitants of thofe places in which it prevails. The ehara&eriftic fymptoms are an inereafed dif- -•charpe of muc«s from the fchneiderian membrane, accompanied with a fever of a contagious nature. The accounts we have received of its appearance as an epidemic, extend as far back as the earlieft ao-tfs of medicine ; it has fince frequently recurred, and has always been attended with fimilar fymp- toms, though defcribed under very different names. It was more univerfal in Europe in 1781 and 1782 than it had ever been known before, and was then fuppofed to have been brought from the Eaft- Tndies to Ruffia, and thence to have pafled to every part ( II ) £>art of Europe in fucceffion.* In 1789 it appeared in the ifland of Jamaica; and in the autumn of $790 the inhabitants of New-York were pretty ieverely affected with it. It feemed to pafs over the country without obferving any particular direction, f allowing few to efcape its attacks; and returned in the fpring of 1791 with unabated violence. Its progrefs was rapid, and though an immenfe number of perfons were affected, the termination was very rarely fatal In the autumn of 1793 the influenza was again obferved in this place, with fymptoms fimilar to thofe which marked its former occurrence. % The fame perfon was liable to be affected every time of its ap- pearance, and fome experienced two or three attacks in the courfe of the fame epidemic. Children and aged perfons, in Europe as well as America, were peculiarly exempt. § The diforder was moil fevere in thofe of bad habits and impaired conftitutions. The fymptoms varied fo much, * Duncan's Inaug. Biffert. De Gatarrho Epidemico. f This was alfo obferved in the influenza of 1782. " It obferved no regular progreifion from any one point of the compafs to another." Med. Tranf. vol. iii. p. 61. % By a gentleman of information from Demerara, I am Informed, that in 1790 and 1793, the influenza made its ap- pearance in that place alfo— that the diforder was fevere, but the event very rarely unfavourable. § Rufh's Medical Obfervations and Inquiries, vol. ii. p. .252. " Out of 7ooboysinChrift's Hofpital, only 14 had it, and they in the flighteft manner." Med. Tranf. vol iii. p. 55. ( 12 ) much, both in the manner and order in which they occurred, that an accurate enumeration of them is ex- tremely difficult. It ufually came on with cold fhiver- ing, alternating with fenfations of heat ; pain or fore- nefs in all the limbs, with a difinclination to motion; obtufe pain in the forehead, dizzinefs, and vertigo; lofs of appetite, naufea, and frequently vomiting. To thefe fucceeded a fenfe of heat, and fulnefs in the nofe, in moft cafes, andfometimes epiftaxis. The eyes be- came ftiff and fore, and a difcharge of a thin acrimoni- ous fluid foon took place from both nofe and eyes, fol- lowed by fneezing and cough. The cough was often one of the primary fymptoms: it was generally at firft dry; but as the difeafe advanced, was attended with a copious expectoration. It was accompanied with difficulty of breathing, unufual fenfation of heat in the mouth and fauces, hoarfenefs, frequently an inflammation of the throat, and consequent difficult deglutition. The fkin was dry and hot ; tongue com- monly white and moift, without much thirfl ; fome- times a diarrhoea was prefent, at other times an in- clination to coftivenefs, but in general the excretions were natural. A great variety was obfcrvable in the pulfe. It was, however, commonly at the com- mencement of the difeafe full and foft; but often be- came in a ihort time fmall and weak. There was fre- quently a confiderable degree of languor, laflitude, and depreffion of fpirits from the beginning. The ( i3 ) The fever increafed toward evening: in the night delirium fometimes came on ; but as morning ap- proached a fweat broke out, which procured a remif- fion of the fymptoms. It feldom continued longer than three days, and very often not folong. With the fever all the other fymptoms difappeared, except the cough, which remained fome time, and then decreafed gradually ill frequency and violence until it ceafed altogether. As the difeafe receded, if convalefcents expofed themfelves to the operation of cold air, and particularly if they wept abroad in cold damp wea- ther, their complaints were often renewed with in- creafed violence. The influenza was frequently much more flight than is here described: many were not prevented by it from attending to their ordinary bufinefs; but in general it appeared, with fome variation, in the form above-mentioned. In a number of cafes, and particularly w*hen the debilitating plan had been prettv liberally employ- ed, all the principal fymptoms of typhus fever took place in the advanced fhges and toward the termina- tion of the complaint. Independent of the intervention of typhus fever, the difeafe fometimes proves fatal, in old and auhmatic perfons, by inducing peripneumonia nctha or the ca- tarrhus fenilis. h ( H J It is alfo fometimes attended with fatality, though, in a more indirect manner, by haflening the approach of phthifis pulmonalis, in perfons whofe lungs are al- ready affected with tubercles. The cough, by agi- tating the lungs and exciting an inflammation in the tubercles, appears to be the principal agent in produc- ing this effect. Repeated and long continued catarrhal affections may perhaps induce tubercles in thofe predifpofed by their form to phthifis; but I cannot believe that the influenza alone, as has been afferted by fome, has ever occafioned it: and I am the more confirmed in this opinion by observing, that in pleurify the lungs may be affected with inflammation, and at the fame time agitated by coughing, without any fuch confe- quence being produced. DIAGNOSIS. INFLUENZA, when it has continued for fome time, may be diftinguifhed from all other difeafes, hy the fymptoms already mentioned ; but in the be- ginning, the diagnofis will be attended with more •difficulty, for obvious reafons. The difcafes with which it is moft liable to be con- founded are common catarrh and mealies. As the fymptoms of common catarrh bear a very great refemblance to thofe which attend influenza, confidcrablc ( i5 ) confiderable attention is necefTary to make the dif- tin&ion. Thev differ principally in degree. The former is, on its rlrit appearance, generally unattend- ed with fever; while, in the latter, the febrile fymp- toms almoft always appear at the commencement of the difeafe, and are more violent: the attack is alfo- more fudden. The diagnofis is not, however, of any confiderable importance, as the mode of treatment in both is very fimilar; and always more fo in propor- tion to their refemblance to each other ; but the na- ture of the prevailing epidemic being confidered, there will remain little room for doubt. We will alfo find much difficulty in diitinguifhing It from the meafles, but may fucceed by enquiring whether the patient ever had that complaint before, and afcertaining whether or not it prevails in the neighbourhood, and whether he has not been expofed to the infection. If it be the meafles, the iruption on the fkin will foon afford a fufficient diftindlion. For- tunately, in this cafe alfo, a miftake will not be pro- ductive of any detriment, as the fame remedies which are Serviceable in the one are proper in the other. PREDISPOSING CAUSES. AS the influenza afFe&ed both fexes and all coniti- tutions with little or no discrimination, it appears that no particular predifpofition was efTentially necef- fary; ( i6 ) farv; for the robuft as well as the delicate, the healthy as well as the infirm,* were fufceptiblc of its attacks. As, however, there are fome eircurnftances which render the body peculiarly liable to be af- fected by difeafes of this nature, and difpofe it to be afflicted with greater violence, it will not be amifs to point them out, efpecially as by a little attention fome of them may be readily avoided. Preceding difeafes, by rendering the body debili- tated and irritable, difpofe it to be operated on by con- tagion, and may therefore with propriety be ranked among the predifpofing caufes. Large evacuations, deprefling paftions of the mind, and a fedentary life likewife operate by debilitating the fyftem. Intemperance, particularly in the ufe of fpirituous liquors, as alfo fatigue, has a great tendency to in- duce predifpofition---exercife, moderately ufed, in- creafes the ftrength of the body, and is one of the be ft tonics employed in medicine ; but, when carried to excels, it produces that fpecies of debility termed by Brown indirect. By a fimilar mode of opera- tion, * Perfons laboring under other complaints are not ex- empt from influenza. When it appeared at Exeter, within a w eek it feized 173 perfons in the hofpital. 44 Thefe hofpital patients, afflicted with fuch various dif- tempers, and under the operation of the moll efficacious me- dicines, were all affected almoft at the fame time and in the fame manner by the influenza." Dr. Cummings'acct. Med. Obf. vol. vi. — $ee alfo Rum's Obf. and Inquir. vol. ii. ( '7 ) tion, but in more dangerous degree, fpirituous liquors prove detrimental. We generally obferve intem- perate perfons more readily affected with contagious difeafes than others, and they recover with greater dif- ficulty. Having long been aecuftomed to the ufe of large quantities of diffufible ftimuli, the remedies commonly employed are too feeble to be of any mate- rial advantage ; and when the termination is fatal, they may, with more propriety, be faid to have fallen victims to their own irregularity, than to the com- plaints which apparently produced their diffolution. Influenza, approaching nearly in its nature to the ordinary catarrh, we may reafonably infer, that thofe caufes which occafion the one, will alfo have a ten- dency to produce the other. Accordingly, we find that thofe who are expofed to the night air, to the operation of cold, either alone or combined with moiftUre, or to viciflitudes of cold and heat, are more particularly and more violently affected.* Cold proves evidently debilitating, efpecially when com- bined with moiflure. According to the common opi- nion, it is injurious riot only by fimply diminifhing the excitement, but alfo by obflructing the perfpira- tion, and determining from the furface to the lungs. The manner in which cold diminilhes the perfpira- iion is a fubject of confiderable difpute. Dr. Cullen C fuppofes * Cold, concurring with contagion, renders it more a&ive. See Cullen's Firft Lines, par. dclxxx. ( iS ) fuppofes It poffeffed of an afhingent power, which, producing a diminution of diameter in the veffels on the fnrface, allows a fmaller quantity of perfpirable matter to efcape. In paragraph xc. of his Practice of Phyfic, he fays, " Befide the fedative 2nd fti- u mulant powers of cold, it is manifeftly alfo a power- " ful aftringent, caufing a contraction of the veffels « ; on the furface of the body, and thereby producing << a palenefs of the fkin and fuppreffed perfpiration ; " and it feems to have fimilar effects when applied " to internal parts. It is likewife probable that this " conftriction, as it takes place efpecially in confe- " quence of the fenfibility of the parts to which the " cold is applied, will, in fome meafure, be commu- " nicated to other parts of the body ; and that thereby " the application of cold proves a tonic power with " refpeftto the whole fyftem." With deference to fuch refpe£table authority, I can- not conceive cold poffefTed of fo many contradictory qualities as Dr. Cullen attributes to it. Indeed, that this apparently aftringent power depends on its operation as a debilitant, appears to me not impro- bable. It is a fa£r, at prefent well afcertained, that the fluids contained in the arteries are not circulated through them by the impulfe of the heart alone, but that thefe veffels alfo poffefs a power of propelling their contents, fimilar to that with which the heart is in- dued ; and, by this mean, the circulation is carried on, in ( «9 ) in the extreme vefTels, in a great meafure indepen- dent of any vis a tergo. This being allowed, it will readily appear that cold applied to the furface of the hody, debilitating thefe vefTels, mnffc diminim their power of circulating their contents ; in confequence of which the quantity paffing through them will be letfened, and a fmaller difcharge of perfpiration induced; the fluids not find- ing the ufual outlet at the fkin, a determination will naturally take place to the lungs, where there is a large extent of furface from which they may be dif- charged. At the fame time, in confequence of the di- mini flied circulation in the extreme arteries, an accu- mulation wili take place in the larger vefTels, which, proving a fHmulus to them, and increafing their ac- tion, will induce the train of febrile fymptoms with which catarrh is attended. Every thing that obftru&s the perfpiration in any conhderable degree, produces a Umilar determination. Hence the remarkable content which fubfifk be- tween the- Jungs and furface, a diminished excretion from one being fucceeded by an increafed difcharge from the other; and, on this principle, it will fol- low, that in affections of the lungs, or membrane in- vejling them, which arife from an increafed flow of fluid, a determination to the furface is one of the mod efficacious and moft natural remedies. The ( so ) The operation of cold air, in producing catarrh, is alfo very ingenioufly explained on chemical princi- ples. In confequence of a diminution of temperature, the atmofphere, which is always expanded by heat, be- comes condenfed into a fmaller fpace, and a greater quantity than ufual is contained within a given cir- cumference. A perfon, breathing this condenfed air, will in- hale a larger proportion of oxigene gas, or vital air, than common, which will afford an ample (lock of materials for chemical decompofitions and combina- tions. The blood being highly oxigenated, becomes more florid and ftimulating; the heat from the evolution of caloric, by the decompofition of oxigene gas, is al- fo increafed, and, by thefe means, the attendant fe- ver of catarrh is formed. Upon entering a warm room, the ftimulus of external heat is added, and a fever more readily induced. During the procefsof refpiration, the water formed in the lungs, by a union of hydrogene from the blood with oxigene, is in greater quantity than natu- ral ; but in confequence of the accumulation of heat, it is difcharged in the form of vapour, and the breath is apparently lefs moift. This theory poflefTes great ingenuity and plaufibili- ty, and has, very probably, much real merit. On any mode C 21 ) mode of the operation of cold, if it is fufficient to in- duce fever, it will augment the violence of the influ- enza : as, in fuch cafes, it acts at nearly the fame- time with the contagion, it is rather a concurring than predifpofing caufe. EXCITING CAUSE. WITH refpect to the exciting caufe, Phyficians are confiderably divided. The principal opinions en- tertained on the fubjecl are the three following. i ft. That it depends on a peculiar ftate of the air, with refpe£t to weight, moifture, or fome more in- fenfible qualities.* 2. That it is propagated by a particular contagious ftate of the atmofphere.f 3. That it is occafioned by contagion but only communicated, like the fmall pox, by intercourfe with the afFe&ed, or through the medium of fubftan- ces imbued with the contagion. As a knowledge of the caufes of difeafes is fre- quently effential and always fatisfadtory, a more mi- nute * This opinion is ably and ingenioufly fupported in an inaugural treatife on the Influenza, by Robert JchnJlo?i, who graduated at Philadelphia, in 1793. His publication acci- dentally fell into my hands juft as this dirTertation was go- ing to the prefs. f The air of places in which the difeafe prevails, is fup- pofed to be impregnated with the contagion which is difperf- ed by the winds to different parts, infecting them as it paffcs along. I 21 ) ante inieitigation of thefe opinions may perhaps be deemed neither impertinent nor entirely ufclefs. The univerfality of the complaint, the celerity with which it proceeds, and the circumftance of per- foils mod expofed being foonefl and moft violently attacked, argue fuongly in favour of the caufes exit- ing in the atmefphere Several inflances are related in proof of this opinion, of perfons being affected fe- veral miles at fea, who had no intercourfe with the land. But the medical focieties 3 which have made the moil accurate inquiries into the nature of this complaint, do not confider thefe accounts as very au- thentic.^ Many contrary facls are alfo recorded, which prove the regularity of progreifion which the diforder oonftantly obferved, and which cannot be reconciled with the opinion above mentioned. It in Ibm^ inftances raged in one diftrit5t, while others in the neighbourhood were entirely free.f The circum- ftance of perfons being affected fooner, and with more violence, who were expofed to the air, is not difficult Soexplain : thofe who went abroad were more like- ly to receive the infection from others who had the complaint; and, by being expofed to fudden changes of the weather, which might produce predifpofition, uld become more liable to be attacked. In . as it prevailed equally in climates extremely different,, * Medical Communications, vol. i. t Pringie's account, Med. Obf. vol. vi. ( n ) different, and as its prcgrefs was not afFecled by any al- teration of weather,* the fuppofition of its depending on the air, uninfluenced by contagion, does nor appear to be well grounded. Irregularities of the atmof- phere, with re fped to weight, moifture, &c. aggra- vate the fymptoms, but do not feem to occafion the diforder. It is true, that by chemical changes in the compo- nent parts of the atmofphere, many difeafes, for which we cannot account, may be induced. From fome changes of this nature, the influenza may have iirft originated; but I am inclined to believe, that it is continued at the prefent day by means of contagion..t The opinion of the contagion's refidmg in the air, is alfo liable to numerous objections. We cannot conceive it pofhble, that this contagion, by no means the moil powerful with which we are acquainted, fhould * Pringle's account, Med. Cbf. vol.. vi. f Dr. Joh-ajlon, in the inaugural ditTertation before referred to, makes the following remark: " The morbific matter, " exciting the difeafe, muft have originated at fprrfe I " and fome where; and a caufe, like "to that which gave rife 64 to it in any one country, at any one point of time, might " produce it in another country, at the fame time, under " fimilar circumilances." This obfervation is top exten- five to have much weight. We may, with equal propriety apply it to the fmall-pox, mealies, plague, and ail other contagious difeafes: they muft have arifeh in the firfi ih- flance, independent of any contagion ; and the fame caufe may recur in any number of countries at any time. This is equally within the bounds of polhbilifv : we -?.re, how- ever, well convinced, that they are at prefent entirely firp- ported by infedion. ( 24 ) fhould admit of diiFufion in a large portion of atraof- phcric fluid, without lofing its active qualities. We arc, it is true, convinced by daily experience, that large quantities of the miafma of marflies, may be blended with the air, or held in folution by it, and by this mode of conveyance, exert its injurious effects on the human body. With the fource of this miafma we are well ac- quainted, and know that continual fupplies of it are* ccnftantly furnifhed by the numerous fens and marfhes with which all parts of the world abound. Yet, not- withstanding this extenfive, this unceafing fupply, we never find the air fufficiently impregnated to convey it to far and diftant parts in all its native virulence. The activity of the effluvia from marfhes, feems to be loft by its being diffufed through, and diluted with the innoxious particles of the atmofphere, that in a fhort time it becomes perfectly inert. Thus it is in the vicinity of marflies, of low and wet fituations, re- plete with pools of ftagnant water, where the air is loaded with perpetual exhalations, the products of heat and moifture operating on the furface of the earth, covered with putrid vegetable and animal fub- flances : it is in fuch places, and in fuch only, that intermittents ufually appear.* The inhabitants of the * It is not my intention to maintain that intermittents are produced only by marfh miafma. It is, however, univer- fally allowed, that this is the moft common caufe of them- ( 2 5 ) the adjacent country, and particularly of upland fitua- tions, are entirely free from all traces of the com- plaint.* If a miafma of this kind can exift in the air, with- out being injurious at any confiderable diftance from its fource, though frefti quantities are conftantly ge- nerating ; it is difficult to fuppofe a contagion which ihall impregnate the air, fwiftly paffing over places in which the difeafe prevails, and when thus difFufed, preferve fumcient activity to infect the inhabitants of other parts over which it glides with the fame rapidity. The univerfality of the difeafe, and the fwiftnefs of its progrefs, can be readily accounted for on the prin- ciples on which the fpreading of other contagious complaints depends. Even the plague, one of the mod: Univerfally fpreading difeafes known, which has thin- ned the inhabitants of the moil populous cities, and defolated the raoft fertile and thickly inhabited coun- tries, is, by modern obfervations, difcovered to be en- tirely independent of any ftate of the air, The infec- tion, which is pofTefTed of the higheil degree of viru- lence, is, by mixture with the atmcfphere, rendered harmlefs in a ihort fpace of time ; and the diforder is only propagated by fome direct mode of communica- tion ; in which cafe the air immediately furround- ing only is noxious, t D That * Sir John Pringle, page 57. f Cuilen's Praft. par. Ixxxii, ( =6 ) That the contagion producing the plague does not operate far from its fource, is proved by well attefted accounts of its prevailing on one fide of a ftreet, while the other is unaffected, and of the Europeans at Con- stantinople efcaping it, merely by confining them- ielves to their houfes, and keeping up no intercourfe with the other inhabitants. The fmall-pox is another inflance of a widely Spreading epidemic produced only by direct commu- nication : before the practice of inoculation was in- troduced, when it prevailed in any place, it raged as univerfally, and was diffufed with as much celerity. The whole catalogue of contagious difeafes might be brought forward to the fame effect ; and as it is fa- tisfactorily afcertained, that the molt active do not im- pregnate the air to any confiderable diftance, a Strong prefumption may be formed, that the operation of catarrhal contagion is confined within fimilar limits. And this prefumption will be further fubftantiated, by a conlideration of the manner in which it proceeded in the late and former epidemics. When the influenza appeared in any place, it foon became diffufed univerfally round in all the neighbor- ing parts, without obferving any particular direction.* Sometimes it could be traced to the arrival of per- fons from fome place already infected. f It * Rufh's Obferv. and Inquir. vol. ii. page 256. ■f Med. Tranf. vol. hi. RuftYs Obf. and Inquir. vol. ii. p. 248. ( 27 ) It appeared earlier in towns than villages-— in villages than detached houfes,* and in general ob- ferved a regular and gradual mode of proceeding. The circumfiance of perfons being affected fooner, and with more violence, who were expofed to the air, is not difficult to explain : thofe who went abroad were more likely to receive the infection from others, who already had the complaint : by being ex- pofed to fudden changes of the weather, which might induce predifpofition, they would alfo become more liable : while, on the contrary, if it depended on the atmofphere, certainly this atmofphere would find its way into the houfes with the greateft facility. From all thefe confiderations, I am induced to em- brace the opinion, that it is communicated in the fame manner with other contagions, by the fufficient- ly near approach to fome perfon labouring under the difeafe, or fome fubftance impregnated with the infection ; and that the air has no agency in the bu- iinefs, except a fmall portion of it immediately fur- rounding the fource of the contagion, which is the medium of conveyance.! It is well known, that the » halitus * Med.Tranf. vol.3. f In this manner we may, in fome meafure, account for contagious difeafes being frequently endemic in particular cities. A great number of perfons having been affe&ed, a large proportion of clothing contains contagion, and fre- quently no inconfiderable quantity of the atmofphere is impregnated with the effluvia; much of which being con- fined in buildings and alleys, where ventilation is but feebly ( 28 ) lialltus arifing from the body of a man in health, forms a little atmofphere round him ; and it is within the limits of this atmofphere that contagion operates. The peculiar nature and mode of operation of this, and every other contagion, is ftill involved in obfcu- rity, and maybe ranked among thofe myfleries of na- ture into which the refearches of man have not as yet been attended with fuccefs. But, as the fcience of chemiftry is rapidly approaching to perfection, and has already thrown great light on the theory of me- dicine, we may entertain a hope, that thefe, and fe- veral other important and obfcure points, which are totally inexplicable on the prefent medical theories, will, at fome future period, be fatisfa&orily elucidat- ed and explained on chemical principles. While, therefore, w T e are unable to explain the caufe, we muft endeavour to obviate the effects ; and, as expe- rience has brought us well acquainted with them, we may expect here to meet with better fuccefs. PROXIMATE CAUSE. THE proximate caufe appears to confift of an in- creafed afflux of fluids to the fchneiderian or mucous membrane carried on, remains almoft ftationary. In confirmation of this remark it may be obferved, that fuch complaints rage with moft violence in calm weather, and are generally re- lieved by florins and high winds, which, on any other prin- ciple, would increafe the diforder. ( *9 ) membrane already mentioned— proving a fource of irritation to it, and thus producing and fupporting the fymptoms which conftitute the difenfe. In fupport of this opinion it may be obferved, that the remote caufes all concur in occaiioning an in- ereafed determination to this part, and that fuch a (late of it is alfo evidently pointed out by the fymptoms. The contagion feems to pollers a peculiar property of caufing this determination, probably by acting as a famulus to the membrane, when inhaled inbreathing, independent of its effects on the fyflem in general; and it is frequently affiited by the concurring opera- tion of cold. PROGNOSIS. IN a difeafe fo rarely attended with fatality, the doctrine of prognofis porTefTes no considerable degree of importance. It is, however, of great advantage, in the cure of difeafes, to have a previous knowledge of thofe fymptoms which may occur, as it will enable us either to prevent their appearance, or guard againil their effects. When the fever attending influenza is gentle ; the cough not very troublefome, and accompanied with a free expectoration ; refpiration little affected, and a difpofition to fweat manifett, there will be no doubt of a favourable termination. if, ( 3° ) If, on the contrary, the patient's health has been injured by previous difcafes; the febrile fymptoms run high, or are followed fuddenly by great debility; the cough is frequent and dry, with difficult or laborious rcipi ration; and the patient is very reRlefs and afflicted with much pain, we may expect a dangerous diforder, and perhaps fear a fatal event. When the perfon af- fected appears to be difpofed by his form to phthifis pulmonalis, and we have rcafon to fufpect tubercles already formed in his lungs ; while, at the fame time, the fymptoms are violent, and the cough in particular continues long, we have reafon to dread its terminat- ing in a complaint which has as yet baffled the powers cf medicine. METHOD OF CURE. THE fever with which influenza is attended, I am inclined to believe, is commonly mild fynochus. I have heard of fome inftances in which the inflam- matory fymptoms were very great, at leafl the reme- dies ufed were fuch as could only be ferviceable in high degrees of fynocha ; but, from the general tenor of the diforder, and the ill fuccefs that too frequently attended fuch practice, I am induced to conclude that real cafes cf violent fynocha very rarely if ever occurred. Concerning I 3* ) Concerning the nature of fynochus fever, Phyfi- cians entertain very different fentiments. One party fuppofes that it is induced by the fame caufes which occafion fynocha ; that it is in fact a real fynocha j and that the. fymptoms of typhus which attend its latter flages, exift in confequence of the previous in- flammatory ftate being allowed to run on to mdircdt debility.* The fupporters of the other fide of the queftion af- fert, that it is only a variety of typhus fever, and that the difference is produced by the caufes of typhus ope- rating on a fyftem pofTeffed of confiderable vigor, or what is termed a fthenic or phlogiflic diathehs. I con- fefs that I am rather difpofed to fubferibe to the latter opinion. In confirmation I would obferve, that the influenza was accompanied, even at its commence- ment, with a degree of languor and deprefiion of fpi- rits, which are never attendant on pure fynocha fever: and though the pulfe and other fymptoms were fuclt as denoted an increafe of excitement, which was al- fo evidenced by the falutary effects of debilitating; re medies; yet this increafe was no more than generally attends the firft ftages of fynochus : and I think it probable, that the very near approach of it, in fame cafes, to fynocha, was occasioned, in addition to the ithenic * This appears to be the opinion of Dr. Rufli, of Phils delphia; and it was on this principle that he recommended blood-letting and cathartics fo ftrenuoufly in the late malig- nant fever — with a view of preventing indirect debility. ( 3* ) fthenic diathefis of the perfon affec~t.ed, by the excit- ing caufes of common catarrh operating at the fame time. To efFc£l a cure, the excitement in the beginning of the difeafe is to be moderated— troublefome fymp- toms are to be alleviated—and the ftrength of the pa- tient, which, toward the clofe of the difeafe, fuffers confiderable diminution, mould be reftored. The firfl indication— to moderate the excitement, is frequently the only one neceffary. It may be fulfilled when the complaint is but flight, by the ufeof the an- tiphlogiftic regimen only: indeed, when moderate in degree, the influenza generally yields to confinement, reft, and a fpare diet. It, however, often happens that thefe are not fufhcient, and we mud then have recourfe to more powerful means. As it was frequently cured by fpontaneous fweat- ing, fudorifics are thus pointed out as the natural and mod proper remedies. Emetics, either given in fuch quantities as to produce full vomiting, or in naufeat- ing dofes, are of great ufe, but particularly the latter. They promote an eafy expectoration, relieve the cough, and at the fame time determine to the furface. The emetics in common ufe are, ipecacuanha, and that preparation of antimony called tartar emetic. For the purpofe of limply evacuating the contents of the flomach, I would prefer ipecacuanha, as it is moft gentle ; and being readily thrown out by the ( 33 ) act of vomiting, the operation is not increafed in vio- lence, in proportion to the quantity taken j but in in- fluenza, the emetic tartar is moft eligible, as it feems to relax the fyftem more powerfully, and can, with greater certainty, be given in naufeating dofes. Emetics, combined with opium, in the form of Dover's powder, are alfo very ferviceable as fudori- fics, efpecially when the warm bath is em-ployed at the fame time. Warm bathing claims confiderable merit, as it proves powerfully diaphoretic. Phyficians have been over-cautious in the ufe of it, from an idea that the ftimulus of the heat would over-balance the relaxing effects of the moifture with which it is combined. By ufing a tepid bath thefe objections will be obviated. Blood-letting has been confiderably employed by fome Phyficians, and an opinion entertained, that the influenza generally and almofl always required this evacuation. This practice may have arifen from the inflammatory fymptoms with which it is at firfl: attended, and particularly from die ftate of the pulfe, which was frequently full: influenced by this ful- nefs, blood-letting was largely prefcribed, which inducing a great degree of debility, was too often followed by death, or a tedious recovery. In fome conftitutions, the inflammatory fymptoms ran fo high, that it was productive of benefit— but fuch inftance? Were rare, and might, ino'ft pro- E bsbly. ( 3+ ) bably, have been relieved by lefs 'powerful and lefs dubious remedies.'* Even where the pulfe and other fymptoms feemed to indicate it, the nature of the epidemic being taken into confideration, Phyflcians of the greateft emi- nence bled fparingly and with caution. From the miftaken opinions of fome, fatal confequences refulted ; and melancholy fadts may be related of perfons, par- ticularly in the fouthern flates, who fell facrifices to the nfe of the lancet. It may with propriety be laid down as a general rule, in contagious complaints, to be cautious of bleeding, as they rarely require, and often will not bear the evacuation. Blood-letting may alfo have proved prejudicial, in violent attacks of the diforder, by not being ufed till indirect debility was already formed, and thus adding dire ft debility to indirect. Hence the impropriety of unneceflfary delay, fince this remedy can only be ufeful in the commencement of the difeafe, and at a more advanced period may prove highly prejudicial. Cold, externally applied, has been recommended in catarrhal complaints, but from what has already been faid concerning it, in the former part of this dilTertation, * " It was feldom necelTary to take blood, fome were relieved by it, but in general it did hurt by depreffing the patients." — Dr. White's account of the influenza, Med. Obf. vol. vi. — Dr.Afh's account, ibid.— Rum's Obf. vol.ii. page 259. — Medical Communications, vol. 1. ( 35 ) differtation, it mud be evident that I am averfe to the life of it. Whether it operates on the furfaee as an aftringent or debilitant, is immaterial; for as its per- manent effect is to obftruft the perfpiration and de- termine to the lungs, it muff confequently be dif- ferviceable ; and this opinion is fupported by facts ; for experience has proved, that, fo far from being ufeful, an expofure to cold has brought on a relapfe when the difeafe was almoft cured. However objectionable I may confider the external application of cold, I am of opinion that internally it may be employed with advantage. It diminifhes the tone of the fyftem, and frequently proves powerfully diaphoretic, and may with fafety be given in every cafe of increafed excitement. Cathartics of a gentle kind, fuch as come under the term laxatives, are very ferviceable in obviating coftivene.fs anddiminifhing the fuperabundant excite- ment, and are more fafe than the draft ic, which are apt to prove too debilitating. The fecond indication — to alleviate troublefome fymptoms, is not productive of much difficulty. When there is a confiderable fixed pain in any part of thecheft, which is augmented by coughing, vola- tile linament or a bliftering-plaiiler may be applied, and will generally remove it. The cough 'is commonly the moft troublefome fymptom, and is principally to be relieved by muci- laginous ( aft ) taginous drinks, which operate on the fauces, fheath- ing the parts and defending them from irritation. Oily mixtures are alfo ufed, but they are apt to grow rancid, and even if they do not, are generally dif- agreeable to the ftomach. When there is confiderable debility, and particu- larly when the patient is of advanced age, gum am- moniac, volatile alkali, and other expectorants of a fiimulant nature, are preferable. Opium, by allaying irritation, moderates the cough, and is raoft effectual. Elixir paregoric, combined with mucilage, is found extremely ufeful, and its utility is principally owing to the opium which enters its compofition. With refped to the third indication — the ftrength of the patient may be reftored in mod cafes by the ufe of a nouriming diet only. When we have reafon to fuppofe that this will not be fufficient, tonic reme- dies, as bark, bitters, &c. will prove beneficial. Where a dangerous degree of debility takes place, the remedies found ferviceable in typhus fever fhould be employed. Previous to concluding, I cannot omit acknowledg- ing nvyfelf highly indebted to Dr. John R. B. Rod- gers, who, to many ufeful precepts which I received while under his tuition, has embraced every opportu- nity of adding the fervices of a friend. The favors he ( 37 ) he has conferred are too important to hefoon forgotten, and will ever intitle him to a high claim on my gra- titude and efteem. I am happy, alfo> in an opportunity of exprefling my grateful thanks to Dr. Nicholas Romayne, both for the information I have received from his va- luable lectures, and for numerous private marks of his friendship* /7= 00= V i