modern origin. I have searched in vain for this opinion among the Greek and other very early writers; while not only their physicians, but even their poets and popular writers, ordinarily ascribe epidemics to exciting causes which reside in the casual qualities of the atmosphere. Some observations I have made on the varieties in atmospherical phenomena, during the existence of epidemical complaints, induced me several years ago to entertain the same opinion; but the limited nature of my own observations prevented me from publishing this opinion, till it had been confirmed by persons of longer and more extensive experience. Never having been in southern latitudes, I wished to know the result of similar investigations in Africa, Asia, and those fertile fields of medical observation with respect to epidemics, which lie near the tropics, and to obtain distinct notions of the opinions of those nations which, in early times, were distinguished for their intelligence and correct observation. I had already noticed certain facts in the history of epidemics, which showed their atmospherical causes, and pointed out similar phenomena in various other complaints not usually regarded as having the same cause.1 It seemed that even the various symptoms of catarrhal affections varied together; so that, at one time, every body's cold would manifest itself in coughing; at another, by nasal obstruction, and so on, as if atmospherical excitants produced the most minute varieties of the symptoms, like specific stimuli, which affect particular organs in a particular manner. It seemed also, on inquiry, that not only domestic animals, but plants, were affected in a similar way, whole tribes being lost by specific disease, in particular seasons, without any very obvious cause. In short, the whole history and local range of pestilences and epizootics corresponded so much with that of aërial vicissitudes, that I entertained no doubt of the true cause. It appeared also, that there were regular periods of general irritability, synchronous with atmospherical changes, of which the ancients likewise had an imperfect knowledge, and which, from their recurring in the course of about twenty-eight days, they ascribed to lunar influence. Among the few modern writers who have entertained similar notions, many have been men of acknowleged ability and experience. The celebrated Sydenham thought there were cycles of diseases ascribable to certain revolutions in the peculiar exciting qualities of the atmosphere, and that the characteristic symptoms of disease would revolve at regular See "Researches about Atmospherical Phenomena," "Observations on the Casual and Periodical Influence of the Atmosphere on Diseases," &c. London, 1817; and particularly the Perenniel Calendar, published by Harding and Co., London, 1824. Articles, Hygeia. though as yet incalculated periods, in the lapse of time. Dr. Meade went further; he could not be ignorant of the facts; but, in compliance with the popular notions of the times, he admitted the suggestions of public fancy which looked to the moon and planets as the original cause. Dr. Darwin, whose ingenuity and research are undoubted, observed the phenomena of atmospherical and periodical diseases, and has illustrated his notions by cases in his Zoonomia. I could enumerate numerous other writers, both in France and Germany; but their works were perplexed by the astrological follies of their times. Of late, Dr. Maclean has published his extensive experience in the Levant, and in India; and has produced many valuable facts, which throw light on the notion which I have long entertained, that pestilence has its source in certain insensible qualities in the air, which, by irregularly occurring, casually fall on people in different parts of the world, but which belong, more or less, to particular places, and constitute the local unhealthiness, in consequence of which the ancients considered particular regions as ill-favored by the genii locorum. The consequences of these opinions respecting pestilence must be important to medical police and to practice. They tend to show the inutility of quarantine, the hurtfulness of keeping the disordered subject in the place where the disease broke out; and they establish the propriety of a prompt removal of the patient into another place, where the epidemic influence may not be at that time exerted. Upon this principle, we see under what circumstances a fever house would be particularly beneficial, and where it would be injurious. The thing required is, that it should stand in a place where the epidemical influence is absent: hence it must be a moveable hospital; otherwise a pest-house may happen to be a centre point of pestilence, wherein the admitted patients cannot recover, because their dwelling is in the midst, and under the full influence, of the exciting cause of the malady. Observations I have made on the aerial electrometer, as yet neither numerous nor correct enough to be published, induced me to ascribe part of the cause of the occult epidemic influence of the air to peculiarities in its electric state. I should wish to see others engaged in this inquiry. The ancients have left a glimmering of this opinion in some of their hymns to the Spirit of Fire. these preliminary hints, I shall endeavor to point out the ancient doctrine of epidemics. HIPPOCRATES is too well known to medical men, as having believed in the efficient power of the air to excite epidemics, to render the citation of his writings here necessary: he likewise acknowleges this influence as constantly operating in certain regions, in a specific manner. His opinions, gathered from the popular doctrines of Egypt and India, and confirmed by observation, seem with little variety to have been embraced by most of the ancient nations we are acquainted with, previous to the relapse of science into the darkness of the middle ages; so that I shall speak of it under the name of the opinion of the ancients. In the Sacred Writings we find pestilence, like famine, ascribed to Heaven, without mention of contagion. In the writings of Pagan nations pestilence is attributed to Jupiter or the combined power of the elements, or to other of the gods; while in those writers who spoke in more philosophical language of the same facts, we find the qualities of the air, happening casually or periodically, and operating sometimes generally and sometimes locally, always regarded as the source of pestilence. Hence, among the former class of writers we find hymns to the gods and to the elements, to the sun, to the moon, to the atmosphere, and to the Spirit of fire or electricity of modern writers; while among the latter class of old writers we find change of place, incense, and cleanliness, prescribed as the means of avoiding the evil. We find the Greek Tragedians, who espoused popular opinion, making those noble invocations to the elements, which characterise also the early writings of the eastern nations, derived from a habit of ascribing human health or disease to the air, and being one of the numerous instances wherein we can explain mythology by referring it to the figurative mode of conveying physical knowlege in metaphorical fables.' The curious reader may also consult the Orphic hymns to the clouds, to the air, and to the heavenly bodies. The ancients, too, in regarding the rising and setting of certain stars and In proportion as we unravel the physical meaning of ancient fables, we shall find reason to admire the truly philosophical doctrine they were intended to convey. Not only Eolus, Zephyr, Flora, Fauna, Maia, Febris, and other personages of antiquity, but the more noble gods and goddesses, as Jupiter, Apollo, Minerva, &c. &c. were emblems of the physical powers of the elements, invented by philosophers, and afterwards taken in a literal sense by the vulgar; hence the mythology, religious rites and ceremonies, and ablutions of various subsequent nations. A single passage from Horace may be selected from numerous others to explain the physical sense in which Jupiter was taken for the atmospherical power, and which will serve as a key to passages in earlier poets. For, regarding the power of a clear cold night to glaze the snowy surface of the ground with ice, he ob serves, -positas ut glaciet nives Puro numine Jupiter. constellations as the causes of aerial changes, looked on them afterwards as agents in the production of human disease and misfor tune. According to the researches I have been enabled to make from published documents, in India similar opinions are to this day entertained. Moreover, throughout the vastly extended and populous nations of the East the atmosphere is regarded as containing the causes of epidemic illness, and the doctrine of contagion is found to be confined to Europeans. The ancients typified pestilence by certain imaginary beings who had a connexion with the air and its phenomena; and the gods of the sky were invoked in times of its prevalence, as is yet done in some parts of the East. But we will leave the writers who conveyed truth in metaphors to those who promulgated its philosophical language. Lucretius combined the latter mode with poetry; and having adverted to the necessity of air to life, he shows the consistency of the counterpart of this opinion, which ascribes pestilence to its occasional bad qualities. Nunc, ratio quæ sit morbis, aut, unde repente De terra surgunt, ubi putrorem humida nacta est, Again, in allusion to its local influence: Est Elephas morbus, qui propter flumina Nili Partibus, ac membris; varius concinnat id aër.2 which Virgil has imitated in his Georgics. I do not pretend that atmospheric peculiarities alone produce epidemic and other complaints, which must be regarded as having a compound origin, and as resulting from the operation of pecu Lucr. lib. vi. 1088. 2 Ibid. 1112. liar qualities of the atmosphere on persons of particular states of constitution; otherwise all persons would be affected, which is contrary to experience. There are, probably, innumerable varieties of temperament, of general habits of life, and of pre-existing diseases, which in different subjects vary the effects of the air: and many persons, perhaps, enjoy a state of health and perfect vital action, which may be capable of resisting its evil influence altogether. It would, probably, be productive of useful results, if physicians of extensive practice would make accurate meteorological registers, during the prevalence of epidemic disorders. I should propose accurate registers to be constantly kept of the weather, but particularly of the atmospherical electroscope; and that the indications of this and other instruments should be particularly noticed at the following times : Firstly, and particularly during the prevalence of epidemics and epizootics, ascribable to atmospheric influence-the plague, yellow fever, various influenzas, during murrains of beasts, a history of which is published at Lyons in France ;'-diseases ascribable to Epidemia. Secondly. In places and among nations where one particular kind of symptom is prevalent, ascribed anciently and technically to Endemia. Thirdly. On the annual recurrence of diseases, as gout, insanity, &c. and of which we have numerous cases,-ascribed to what is called the periodus annuosa. Fourthly. At the monthly periodical returns of diseases, or exacerbation of symptoms, as in insanity, head-ach, general irritability, &c. which occur to different persons at different times in the month, called periodus menstrua. Are these periods synchronous with those atmospherical changes happening near and ascribed to the conjunction and opposition of the moon? They have appeared to me to be so in a great many cases; but the observation wants the confirmation of time. Fifthly. We should notice whether any changes in the instruments of electricity are found at the periodi diurnales, those critical periods of the day or night when the crisis, the returns, or other phenomena of many diseases, are noticed; when flowers open and shut, as the goat-beard does at noon. The place of the moon, too, should be accurately noted. Far as I am from indulging in the theoretical reveries of the middle ages about lunar influence, yet when I consider the influence of the moon on the tides, on the variations of the barometer, and on the changes of the weather, I can conceive it possible that she may 'Recueil de l'Histoire des Epizooties, 8vo. Lyon, 1797. |