Upon the whole, I have, in the following work, humbly attempted to follow what I conceive to be the only true method of cultivating any practical art, that is, to collect and compare a great number of facts. A few individual cases are not to be relied on as a foundation of general reasoning, the deductions from them being inconclusive and fallacious, and they are liable to be turned and glossed, according as the mind of the observer may he biassed by a favourite prepossession or hypothesis. It has been my study to exhibit a rigid transcript of truth and nature upon a large scale, and to take the average of numberless particular facts, to serve as a groundwork for observation; and I have endeavoured to analyse and collate these facts, by throwing the monthly returns that were made to me into the form of Tables, as the most certain and compendious way for finding their general result. If the materials are not sufficiently ample, or if the method should be found faulty and imperfect, let it be remembered, that I had no example to go by in this field of observation. It is to be regretted, that ages have passed without any attempts being made to transmit regular records of this kind to posterity. It would not only be extremely curious, as a piece of natural knowledge, but would conduce greatly to medical improvement and public utility, were we possessed of such information concerning the causes and nature of the diseases prevailing at sea, in various circumstances of weather, climate, and diet, in remote ages and countries, or even in our own age and country, as might enable us to compare them with present facts, and to ascertain more precisely the means of preventing and removing such diseases. The favourable reception which the first edition of this work has met with, renders it necessary to offer another to the Public; and though no new opportunities have occurred of making additional observations in the naval service I have endeavoured, during the last two years, from a pretty extensive experience in a large hospital, and from private practice, to add some new information on some practical points; and I hope this edition will be found throughout more full and correct than the former. The method I propose to follow in this work, is, First, to deliver the history of the different voyages and expeditions, so far as relates to health, giving an account of the prevalence and nature of the diseases and mortality on board of ships and in hospitals. Secondly, To deduce, from observations founded on these facts, and also from the former experience of others, the causes of sickness in fleets, and the means of prevention. Thirdly, To deliver some practical observations on the cure of the most common diseases incident to fleets, particularly in hot climates. OBSERVATIONS. PART I. BOOK I. Comprehending the MEDICAL HISTORY of the FLEET, from March, 1780, till August, 1781. CHAP. I.