and without the occurrence of a single case of fever,' writes the Governor, either in the garrison or the city, which can be traced to the ship or to her crew.' This great experiment, or rather series of experiments, carried on daily for so long a period, is the more honourable to Sir W. Colebrooke, the Governor, to the leading practitioners, and to the other influential persons by whom he was steadily supported on this occasion, inasmuch as they were all fully aware of the prejudices and fears prevailing, in countries where the disease is unknown, respecting the supposed communicability of yellow fever by contagion. H. M. S. Highflier' arrived at Jamaica from St. Thomas on the 23rd of December under exactly the same circumstances as the Dauntless' at Barbados, and received free pratique immediately. Dr. Watson, the able physician of the hospital at Port Royal, fortified in the opinion at which he had arrived by the results of many similar experiments in that place, recommended that there should be no interruption to the Highflier's' people communicating with the shore, but intimated that it would be dangerous for strangers to be exposed to the atmosphere of the ship so long as the disease continued in her. The sick were accordingly received into the hospital at Port Royal, where they were mingled with the other patients; and the officers and crew enjoyed free communication with the shore. The result of this experiment,' says Dr. Watson, of exposing so many persons (who may fairly be presumed to be susceptible) to the contagion of yellow fever-to direct communication with the 'disease has been, as far as it goes, highly adverse to the 'imposition of quarantine in such cases, for no single instance of any kind of fever followed the landing of the "Highflier's" sick or the free intercourse of her officers and people with the 'town, either in the hospital or in the town.' It has excited 'considerable surprise here that the "La Plata" was subjected to quarantine on her arrival in England, because she had yellow fever on board, after quarantine measures had been denounced as inefficient by the Central Board of Health. Reflecting on the rapid and constant intercourse which now 'takes place between England and the countries where yellow fever is endemic,-bearing in mind, too, the atrocity of confining people in a pest ship, in places where no proper houses are prepared for their reception, and the manifold annoyances which must accompany necessary or unnecessary quarantine, I have made the above representation, which proves that in 'the instance of the "Highflier" no harm resulted from landing persons who were in the worst stages of the malady; such

examples will encourage the advocates of the more humane 'system of dealing with such epidemics as furnishing evidence ' of the uselessness of quarantine.' According to Dr. Chamberlaine, who had been health officer at Kingston for twenty-five years, yellow fever patients were frequently landed from the mail steamers and received into lodging-houses at Kingston, but the disease did not extend to a single individual there; some yellow fever patients from the Orinoco' also were received into the Kingston Hospital, and placed in beds adjoining those in which were patients suffering from other diseases, which is the common practice in the West Indian hospitals, so convinced are the medical men there of the non-contagious character of this disease. In consequence of the Report of the General Board of Health, which by direction of Lord Palmerston had been furnished to the authorities at Cartagena (New Granada), the quarantine regulations formerly enforced there against yellow fever had been rescinded, and patients were continually landed from the West Indian mail steamers during the epidemic season of 1852, without in any instance communicating the disease to others. And we learn from our consul there, that the cases of yellow fever at Cartagena were exclusively confined 'to persons landed from the Steam Packet Company's ships, and in no way affected the health of the town.' Two officers and ten men from the 'Dee' were received into the general hospital, and with the exception of two who were in the last stage of the disease all returned to their ship convalescent, but the disease was not communicated to any other person. The mail steamer Esk,' from St. Thomas, arrived in November at Nassau with eight yellow fever patients on board; she received free pratique, six of the patients were landed and distributed in three different houses in the town, two remained on board; all had free intercourse with their friends and attendants, and the disease did not attack any other person, though it had theretofore prevailed and proved very fatal at Nassau.

Yellow fever being a disease alien to our soil, our sole knowledge of it must be obtained from other climes. But before giving credence to narratives of the rise and progress of yellow fever epidemics, we must be satisfied not only that our informants had the desire, the perseverance, the leisure, and the ability to elicit, but that they actually elicited the whole truth, and nothing but the truth. In a well-educated highly civilised community, with free discussion, and a numerous body of scientific men to observe and compare facts, and the time, order, and manner of their occurrence, this security may be obtained, but it cannot be obtained elsewhere. We must have all the facts

before us; not the inferences or presumptions of a partisan expecting preferment if he can-by presenting us with fortuitous coincidences in the guise of cause and effect-fabricate a plausible case to prop a falling superstition, by whom what is hoped is readily believed, and what is believed is confidently told. What he asserts confidently he is bound to prove clearly; if the evidence be defective, the deficiency cannot be supplied by conjecture, the failure is fatal; we must have proof, not surmises; if the evidence be not complete in all its parts, cadit quæstio.

From very early times,-from the days of Sir Thomas Brown, upon whose evidence that natural diseases were heightened to a great excess by the subtilty of the devil co-operating with 'the malice of these we term witches, at whose instance he doth these villanies,' Sir Matthew Hale convicted two poor women of witchcraft,from the days of Dr. Mead, upon whose advice quarantine was established in Great Britain, and who, as we learn from Sir Henry Ellis, was deceived by De Foe's fabulous 'Journal of the Plague,'-the medical profession has betrayed a remarkable tendency to credulity on the subject of the origin and spread of epidemics, and has from time to time allowed itself to be deluded by fables much less interesting than the novel which beguiled the sagacity of Dr. Mead, and not more truthful than the Great Discovery of Witches in Denmark,' upon which the Philosophic Enquirer into Vulgar Errors unwarily founded his opinion, when giving before the devout Lord Hale that evidence which sent two helpless women to the gallows. Chronologically arranged, the tales of yellow fever epidemics alone would supply materials for an interesting additional chapter in the History of Fiction. The curious in such literature will find them collected with great care in Copland's Dictionary of Medicine,' titles Pestilence, Hæmagastric,'Protection from Foreign Pestilences.'

The phenomena of epidemics-of those diseases which excite alarm by a great number of deaths following the same symptoms in a short space of time-have in all ages excited attention; with the advance of civilisation and knowledge the spirit of enlightened inquiry arose, and the doctrine which ascribes pestilence to local causes, and which is found in many ancient writers, was given to the world. These local causes are not, however, readily acknowledged by persons living within the sphere of their influence, for the doctrine that epidemics, or diseases attacking numerous persons simultaneously, spread by contact of the healthy with the sick is far more acceptable in that state of mind which pestilence engenders:

* 6 St. Tr. 697.

'In every clime,' observes Humboldt, men fancy to derive consolation in the idea that a disease which is considered pestilential has been brought from abroad. This belief flatters the national pride. To inhabit a country which produces epidemics might be deemed a humiliating circumstance; and it is more satisfactory to consider that the malady is a foreign one, and that its breaking out has been merely the effect of an accident against which it will be easy to guard in another instance. The people immediately adopt this explanation of the origin of the disease, because it is easily comprehended. The medical men, on their side, in general rest satisfied with it, because the word importation relieves them from all responsibility, and from the trouble of investigating the nature and real cause of the disorder. From this has arisen that remarkable facility with which the doctrine of importation has been eagerly received by all classes when an epidemic manifests itself in a country, and a vessel, a traveller, or a parcel of goods arrive at the same time. So it is that the Havannah, Vera Cruz, and the seaport towns of the United States, constantly accuse each other of the importation of the yellow fever during the summer months, just as the inhabitants of Egypt refer to the arrival of Greek vessels the appearance of the plague; when in Greece and Constantinople, the disease was attributed to vessels coming from Alexandria and Rosetta.'

Let an epidemic rage, and to a mind overpowered by alarm, 'that takes the reason prisoner,' the doctrine that the pestilence spreads by contact is the most satisfactory, and therefore the most easily believed; it requires no exercise of the reason from a mind which has for the time been abandoned by its reasoning powers. To a mind of which the perceptive powers are deadened, it apparently appeals to facts; and to a mind possessed by fear, it offers the consolation of safety, by withdrawal from the sick and the dying, and thus escaping the dreaded phenomena altogether. This doctrine of the spread of epidemics by contagion, though apparently originating with the vulgar, gradually insinuated itself into medical literature in a dark and superstitious age. But no one in our times has ventured to assert that he ever personally traced the course of an epidemic, from its source, by contagion; for no man has himself personally seen the introduction of an epidemic, and traced its progress from person to person through an entire locality; and this supposed personal observation of the rise and progress of an epidemic resolves itself, when closely examined, into the mere adoption at second hand of the reports, or rather the gossip of others, the ignorant, the prejudiced, and the credulous in a time of panic, people of the lowest class and dwelling in the vile haunts of fever.

The epidemics of Jamaica,' say the Board of Health of that island, come and go and are forgotten.' Not one single epide

mic witnessed by the health officers there could be attributed to importation.*

Correct observation has established that for a considerable time before the disease has seized a number of persons sufficient to strike alarm by showing that its presence epidemically is no longer doubtful, it has at intervals of time attacked individuals apart from each other, presenting all the symptoms and attributes of the disease, even the most malignant. These early cases of the epidemic are identical not only with the great mass of cases which prevail when the disease is at its height, but also with the ordinary scattered (or sporadic) cases of the same disease which appear in the sickly season of the year in the climates appropriate to yellow fever, and which sporadic cases are also occasionally characterised by the same malignant symptoms as mark the disease when the state of the atmosphere causes it to prevail so extensively as to become epidemic. These sporadic cases, in themselves indisputably proving the local origin of the pestilence, having been always known and observed, render the disease familiar to the practitioners of the place, and the occurrence of a few such cases excites of course no alarm; but when the atmosphere becoming pestilential produces an epidemic of the disease, the few first straggling cases of yellow fever, which of themselves have created neither surprise nor apprehension, are ere long followed by a great number of similar attacks close together in space, almost simultaneous in time, and of high mortality, and the maximum is now soon attained which is vulgarly considered to be the epidemic, and the causation of which is then diligently sought for in contagion from some foreign source, the real beginning of the epidemic having passed unheeded.

The uncertainty of the period of incubation is a favourite instrument for tracing an epidemic to importation. When a swarm of cases, nearly simultaneous, announces the outbreak of an epidemic, if any one of them can be connected, however remotely, with a low lodging frequented by seamen, or with a bag of foul clothes or an old jacket from a ship, this convenient 'period of incubation' will remove all difficulties. Though the disease may not have manifested itself in this chosen instance until some days after it had appeared in several others, this single case is antedated by such a prolongation of the incubative period as may be necessary to make it precede its predecessors. This is accomplished, by the process of self-deception, in the fol

* Yellow fever patients constantly arrive at Kingston, and for the last twenty-five years have never been put in quarantine. (Jamaica Report, p. 41.).