The reports of consumption, in other parts of Great Britain, correspond, in a great degree, with the accounts of its prevalence in London, and, therefore, render this ascription of its causes and origin unsatisfactory.

Dr. Lettsom, however, in a letter to dr. Hosack, on the diseases of London, (Amer. Med. and Phil. Reg. vol. 2) says, "Whilst the phthisis pulmonalis is rapidly increasing in America, and in the european continent, it is diminishing here. The croup is less fatal, in consequence of the immediate and free use of the lancet, and of leeches, with purgatives, than heretofore; nor is angina scarlatina either so frequent or so fatal. The typhus is almost extinct, and the cholera morbus is unfrequent; and, as far as my experience extends, the syphilis is milder, or easier cured; and, lately, such has been the prolongation of health and life as to lessen the premiums of insurance considerably."

Out of 19,954 deaths, in London, in 1808, 5,220 are ascribed to the consump tion. The christenings, in that year were 19,906, nearly equal to the burials.

In 1809, the healthiest year which London ever enjoyed, there were 16,680 deaths, 4,570 of which were produced by the consumption; the number of christenings was 19,612, making the excess of births above the deaths nearly 3,000. (See the London Annual Medical Review and Register, for 1808 and 1809.)

Dr. James E. Smith says, that "In Italy, consumptions are found to be very contagious, though less evidently so in England." It is intimated, if my memery serves me, in that excellent work, the Emporium, that the general use of cotton shirts, etc. may have a pernicious influence in producing this disease. Its increased fatality in Europe, as well as in America, is, probably, owing to a complication of causes; and, indeed, the periodical prevalence and disappearance of certain diseases, must be classed among those arcana which providence has concealed from man.

Salubrious as the climate of Madeira is generally reckoned, we find, that even there pulmonary diseases cut off a great number of the inhabitants. Of the various districts of North America, New-York has been considered, by many, as being especially favoured with regard to the mildness of its seasons; and the changes of its weather were referred chiefly to the difference in the prevailing winda Among a series of interesting remarks on the climate and diseases of New-York, made by lieutenant-governor Colden, about seventy years ago, and inserted in the American Medical and Philosophical Register, vol. 1. this medi

cal philosopher observes, "The air of the country being almost always clear, and its spring strong, we have few consumptions, or diseases of the lungs." "People inclined to be consumptive in England, are often perfectly cured by our fine air; but if there be ulcers formed they die. The climate grows every day better, as the country is cleared of the woods; and more healthy, as all the people that have lived long here testify. This has even been sensible to me, though I have been but about twelve years in this country; I, therefore, doubi not but it will, in time, become one of the most agreeable and healthy climates on the face of the earth. As it is at present, I prefer it to the climates of England, and, I believe, most people that have lived any considerable time here, and have returned to England, will confirm this."

If the climate of New-York was formerly thus mild and healthy, and a constant amelioration in its temperature is consequent upon our numerous settlements and improvements, as has been maintained by many distinguished writers, to what shall we ascribe the extraordinary mortality occasioned by pulmonary consumption at the present day? none will deny this disorder to be influenced by climate, and independent of effects arising from particular employments, and modes of living; but we will, perhaps, find the most satisfactory answer to this question, in considering phthisis in its various forms as the offspring rather of increased dissipation, of great imprudence in dress, and of consequent exposure to sudden changes of temperature, than of any peculiarity in our climate and

seasons.

This opinion of the origin of this disease is further confirmed, upon reflecting upon its nature. Consumption is reckoned, by a practical observer, dr. Hosack, who has devoted a large share of attention to this subject, (Quarterly Reports on the Diseases of New-York,) as being in a great majority of instances in its primary or forming stage, an inflammatory complaint, the effects of cold; and as yielding to the treatment indicated for the removal of inflammation, when affecting other parts of the chest.

We have, in many instances, employed blood-letting with the most happy effects, in many cases of incipient phthisis, even where strong hereditary predisposition existed. Indeed, we are induced, from some late observations on this subject, to express the opinion, that in the commencement of phthisis, as in peripneumony, blood-letting is not sufficiently employed, but is two frequently neglected until the inflammation has so far extended that suppuration becomes inevitable. Nor do physicians, in general, appear to have been sufficiently attentive in describing the symptoms characteristic of the first or inflammatory stage of phthisis, and, consequently, have been regardless of that active antiphlogistic treatment which alone can prevent the tuberculous or suppurative stage. Inasmuch as suppuration, or a purulent secretion from the lungs necessarily implies

preceding inflammation, we conceive too early attention cannot be given to the premonitory symptoms which announce the inflammatory stage, but which are frequently so inconsiderable, being seated in the less sensible, the cellular portion of the lungs, that both physician and patient are alike regardless of the present symptoms, and of the consequences to which they lead. Instead, therefore, of trusting to sirups, anodynes, pectorals, or ptisans, to allay the occasional dry hacking cough and pains of the chest, which indicate the first approach of the disease, we earnestly recommend the same active treatment by blood-letting, blisters, and other means of diminishing excitement, as are employed in the treatment of a pleurisy, or any other acute inflammation; and we could add, in confirmation of our view of this subject, many recent cases, in which the practice here recommended has been attended with the most happy results." American Medical and Philosophical Register, vol. 2.

NOTE 39.

Contagion and infection are subjects which have been fertile of discussion and controversy. Their peculiar character, and the agency which they exert in giving origin to, and modifying the form of, diseases, seem to have attracted, at a very early period, a large share of attention. Among the ancient physicians we find to pen, in express terms, stating the manner in which plague is communicated; et quidem quod aeris pestilens febrem afferre consuevit, nemo sanæ mentis dubitavit, sicuti et pestilenti morbo laborantium conversatio periculosa, ne inde contagium contrahatur, quemadmodum ex scapie et lippitudine. (Galen de Differ. Febr.) Livy, the historian, appears to have been duly sensible of the power of contagion; et primo temporis ac loci vitio, et ægri erant, et moriebantur: postea curatio ipsa et contactus ægrorum vulgabat morbos; and in describing a pestilential disorder which prevailed in the early part of the fourth century, A. U. C., he again remarks, vulgatique contactu in homines morbi. (Lib. iv. cap. xxx.) Soon after the restoration of learning, when the stock of knowledge preserved by the arabians was increased by new facts and discoveries, and medical science was augmented by the laborious investigations of that prolific age, we find Diemerbroeck and others devoting especial attention to this subject. Though a difference of opinion existed, it is manifest that a large majority of physicians maintained the general doctrines of contagion.

At a more recent period the great mortality which accompanied the different attempts at colonization in the West-India islands, and on the coast of Africa

called the minds of medical observers to the peculiar nature of intra-tropical diseases. The appearance of the yellow fever at Boulam, in 1793; its general prevalence in most of the West-India islands; and subsequently, its more extensive diffusion in different parts of the United States, have been the means of enlarging the original limits of the controversy, and have given to the discussion an interest inferior to none among medical inquiries. Pre-eminent among the european authors who have entered upon this discussion, may be considered the celebrated dr. Chisholm and dr. Haygarth, whose respective writings on the malignant yellow fever are monuments of the learning and talents of their authors, and may be pronounced the most able and satisfactory works in support of the doctrines which they have espoused; as the writings of our late distinguished countrymen, doctors Rush and Miller, may be referred to as containing the best summary of the theories which these authors have embraced.

Although the specific nature of the matter by which certain diseases are propagated is still imperfectly understood, yet it were idle to deny the existence of contagion; and it is certain we have recently ascertained, in no inconsiderable degree, the laws by which it is governed. "In the present state of medical knowledge," says the Edinburgh Review, "it would not, we conceive, be at all more absurd to deny the existence of fever altogether, than to maintain that it is not propagated by contagion." Review of Dr. Huygarth's Letter to Dr. Percival.

Au attempt was made by the late dr. Richard Bayley, of New-York, te establish a distinction between contagion and infection, and to Biserinfine the diseases arising from these two different sources. (Treatise on the, Arno Fever of New York, 1795.) This distinction has been adopted by some european physicians, and, among others, by dr. Joseph Adams, but without the due acknow ledgment.

About the year 1797, dr. Mitchill promulgated his ingenious doctrines on the pestilential fluids; and in 1804, dr. Edward Miller made public his Attempt to Deduce a Nomenclature of certain Febrile and Pestilential Diseases from the origin and nature of their remote cause. Medical Repository, vol. 1 and 7.

In July, 1803, a new theory on the laws governing the communication of contagious and infectious diseases, was published by dr. Hosack, in a letter addressed to dr. Colin Chisholm. (Vide Edin. Med. and Surg. Journal, vol. 5.) Dr. Hosack admits the distinction proposed by dr. Bayley to approach nearer the truth than any other that had hitherto been offered, but he does not consider it as presenting a view of the whole truth. Those diseases which are communicable from one person to another, and are generally considered of a contagious or infectious nature, are distributed by dr. H. into three classes. First, such as are communicated exclusively by contact; as itch, siphylis, sibbens, laanda of

Africa, frambesia, elephantiasis, variola vaccina, and hydrophobia: secondly, such as are communicable by contact and the atmosphere; as small pox, measles, chicken pox, hooping cough, scarlatina, and cynanche maligna: thirdly, those diseases generally communicable only in an impure air; as plague, yellow fever, typhus, in its various forms, and dysentery.

The following extract is taken from the introductory part of dr. Hosack's letter:

"The visiter or attendant contracts disease from one of two sources, either from the filth of the sick room, or from a specific something issuing from the body of the sick, the consequence of the peculiar disease under which he labours. If a person visiting another ill of the yellow fever, or plague, derives his disease from the impure atmosphere of the apartment, I ask, how it happens, that in all instances he contracts the same disease with that of the person whom he visits? why is his disorder not an intermittent, a remittent, jail fever, or dysentery, which are considered the usual produce of filth ? if he derives any thing specific from the sick, his disease is then assuredly not to be considered as occasioned by the atmosphere, but depending on the peculiar condition of the fluids, or state of the system, induced by the action of a specific poison, in other words, it is to be considered a contagious disease. The distinction proposed by dr. Bayley, inasmuch as it does not account for the communication of the peculiar form of fever or disease which is thus propagated, I therefore consider to be insufficient to account for the circumstances, attending the communication of those diseases to which it is applied. That I may not be misunderstood, I will suppose A to be ill of dysentery, a disease well known to be attended with a peculiar train of symptoms; he is in a small confined apartment, his person is neglected, the atmosphere round him is rendered impure and offensive; under these circumstances B visits him, and a few days after is also taken sick with the same disease, attended in all respects with the same dangerous symptoms whicha characterize the disorders of A. Dr. Bayley and those who adopt the doctrine of infection as opposed to contagion, consider the disease of B to proceed from the impurities of the air of the chamber, and not from any thing peculiar emanating of secreted from the body of A. But as we may, without hazard, visit an equally althy chamber where C lies ill of cholera morbus, or D with a broken limb, I therefore ascribe the disease of B to something more than the impure air of the chamber of A. I ascribe it to a peculiar virus generated in his system by the disease under which he labours, and communicated by his excretions to the surrounding atmosphere, rendering it thus capable of producing the same disease in those who may be exposed to its influence."

Europe is already greatly indebted to that spirit of investigation which charActerizes the professors of the healing art in this cometry; a spirit which has p