The number of in-door patients, and of cases of fever amongst these, will give some idea of the magnitude and importance of the establishments. In the Colonial General Hospital, from the 1st February, 1842, to the 30th June, 1848, exclusive of six months when the author was on leave of absence, he informs me, that 22,036 cases were under treatment, of which 11,420 were of idiopathic fever, using the term in contradistinction to fever of the sympathetic kind, such as arises from the phlagmasia and exanthemata; and that in the Seaman's Hospital during the same period, with the same exception as to time mentioned, and other six months, the report of which was not at hand for reference, the admissions were 6,295, of which 1,439 were instances of idiopathic fever. The Lunatic Asylum and the Small Pox Hospital are merely small auxiliary institutions; in the former the admissions were 197, in the latter 150. The reports on these hospitals, published at half-yearly periods, are exemplary documents, and in themselves afford strong proof of the zeal and ability engaged in the service.

That the Author himself experienced the disease, may be mentioned as another circumstance in favour of his undertaking. He may truly say, with the great historian of the plague at Athens *: 66 Having myself had the distemper, and having seen others suffering under it, I will state what it actually was, and will indicate, in addition, such other matters as will furnish any man who lays them to heart with the knowledge and the means of calculating beforehand, in case the same misfortune should ever again occur."

In an Appendix some additions have been made bearing on the subject of the treatise, the most important of which are the papers on the use of quinine in the treatment of the fevers of the West Indies. Of these, those by the Author he favoured me with when I had charge of the medical department in the West Indies. They were circulated widely at the time amongst the medical officers of the Command; were thus instrumental

in making better known and in bringing into use this powerful remedial means; and they are now published at my suggestion, with the hope of making them more extensively useful.

In conclusion I would observe, how very desirable it is that some principles should be established as practical rules on the emergency of an outbreak of Yellow Fever, so that those concerned, whether medical officers, or general officers, or civil authorities, may be prepared to act with as much confidence and decision as possible when the disease appears. I am not without hope that this work may promote the desideratum by tending to prove,

1st. That the disease is of local origin, and not infectious or contagious.

2ndly. That its exciting cause, whatever it may be, is limited as to space of action, and may be avoided by change of place; and further, that though removal to a short distance, even if the ground be apparently similar, may often be sufficient, it is safest to make the change to a spot altogether different in its character from that where the outbreak took place.

3rdly. That the newly arrived from a cool or cold climate are most liable to be attacked by it, and ought therefore as much as possible to avoid the localities where the disease is prevalent; and accordingly, that bodies of men employed in the public service, on arrival in the West Indies, unless the exigencies of the service absolutely require it, should be kept from such spots.

4thly. That the natives of the African race, and of the mixed coloured races, though not always exempt from the disease, are comparatively little liable to contract it; generally they may be considered safe from it, as well as from an attack of remittent fever; and consequently that men of the West India regiments, all of whom are Africans, should be preferred for service in unhealthy situations and seasons.

5thly. That the tendency to contract the disease in the instance of whites is less in those coming from warm climates, as

the South of Europe, than from cold, as the North of Europe and North America; consequently that troops ought not to be brought from England and Canada to the West Indies, but rather from the Mediterranean stations or the Cape of Good Hope.

6thly. That the disease commonly does not recur in the same person; and, consequently, those who have had the disease are best fitted to act as nurses and attendants on the sick, if treated where the disease originated.

7thly. That Yellow Fever, it would appear from its past history, has been variously modified, subject to many complications of a perplexing kind, which ought to influence the treatment, and which require to be studied, and, as far as possible, determined, to fix the mode of treatment likely to be most successful in each epidemic.

8thly. That though it has invaded bodies of men occupying apparently healthy quarters, and under circumstances favourable seemingly to health, yet most commonly it has broken out in situations of a different character, where the drainage has been defective, where there has been crowding and neglect of cleanliness, in brief, a complication of circumstances, more or less of an unwholesome kind, such as are likely to promote the action of a specific exciting cause; consequently, that all measures of a sanatory kind cannot be too sedulously attended to with a view to the prevention of the disease.

9thly. That the disease hitherto has been of periodical recurrence, not yet calculable, its cause being unknown,-and that though occurring oftenest in the coolest season, not invariably so, and that no uniform kind of weather, as far as observations hitherto extend, has been connected with its appearance; and, consequently, there can be no certainty at any particular time as to its non-recurrence.

J. D.

Lesketh How, Ambleside,

Dec. 31. 1849.

PREFACE.

WHEN the late epidemic Yellow Fever commenced, the medical gentlemen of Georgetown then in practice were without personal knowledge of the disease; for those who had seen the epidemic of 1819 had retired from practice or were dead, and had left no record of its local peculiarities and treatment behind them. In some measure to prevent the inconvenience of a similar blank in the medical history of the colony, the Author undertook to write the present memoir. The materials of it are derived from his clinical notes of private cases, from analyses of the registers and case books of the hospitals under his charge, and from a fresh recollection of the general circumstances of the late epidemic.

The subject is capable of a much more minute and extensive dissertation; and the Author hopes that the present contribution may be the means of eliciting, in a similar manner, and for a similar end, the views of several of his professional brethren of the colony. The value of such contributions would not be of local importance only. From the discrepancies of medical writers on some of the most prominent facts regarding Yellow Fever, there is no doubt that the disease is subject to many modifications, the whole of them probably arising from differences of climate (taking the word in its extensive signification) within the Yellow Fever zone. It is likely that the

*

* [That Yellow Fever is subject to variation, connected with season and

Demerara type would represent a large area on a chart of the disease; so that the collective information which can be furnished from the late epidemic may not have to lie useless till our next visitation, but be immediately applicable to the relief of human suffering and the elucidation of disease elsewhere.

The pathological drawings are chiefly the work of a young sailor who was admitted to treatment in the Seaman's Hospital.* After he recovered from his attack of the prevailing epidemic, his talents were discovered, and, for a considerable period, he continued to be employed by me as draughtsman for the hospital. It is scarcely necessary to state that the drawings are bonâ fide representations; and though several are somewhat coarse, their verisimilitude is striking.

For assistance in the analysis of the case-books and register, I am much indebted to Dr. Fowler, the present chief resident surgeon of the Seaman's and Colonial Hospitals.

The preliminary remarks are intended to show (in botanical language) the habitat of our type of Yellow Fever, and further to identify it by pointing out some of the ordinary influences which the locality and climate seem to exercise over the population.

locality, and with obscure circumstances that at present cannot well be appreciated, is proved by extensive experience. The fever of one season, or place, may be far more malignant, that is with greater tendency to fatal termination, than of another season, or of another place; in one epidemic or endemic, the lancet may be used cautiously with advantage, or even boldly; in another not without the greatest risk of bad effect. These remarks apply to epidemic diseases generally. We are informed, by Sydenham, how difficult he found it, on the breaking out of an epidemic, to determine on the best mode of treatment to be employed in it,—and how he came to a decision only after "ingenti adhibita cautela intentisque animi nervis ;" an example well deserving of being followed. A series of monographs exhibiting distinctly the varieties of Yellow Fever, in its several complications, could they be written by one observer free from the bias of hypothesis, would be invaluable for practical purposes; but, I fear the absence of such a bias with the possession of every other qualification, is too much to expect.] - ED.

*

[Of the drawings which accompanied the MS. only a select number have been published, · some of the most characteristic, the Editor, to whom a discretionary power was allowed, not considering it right with a view to just economy to insert the whole. He has pleasure in adding that the remainder have been presented by the Author to the Museum of Pathological Anatomy of the Army Medical Departments, where they can be consulted by inquirers interested in the subject.]-ED.