"fons et origo mali ;" by it the dysentery was excited, and, only by its removal could it be removed! This view of the disease I conceive to be of great consequence, and trust it will meet with due consideration from the profession, inasmuch as it is a view not taken up hastily, or out of complaisance to a favourite hypothesis, but deduced from nearly two hundred cases, and built upon the corner-stone of morbid dissections. I hope the time is not far distant when more accurate observation will teach medical men at large, to regard this disease merely as secondary to, and symptomatic of hepatic affection, and to seek its more immediate cause in a morbid condition of that important organ, the liver. Whatever may be the mode of connection between hepatic derangement and dysentery, I am convinced from analyzing my own sensations, as well as from having counted in others the links of the pathological chain, that, at least in tropical climates these two diseases are connected like cause and effect. The practice which most readily removes the disease, too, tends much to confirm me in this conviction; for the "mercurial method" I have pushed to a great extent, and its results have been such as to give it a very decided preference in my estimation. Calomel, (that great specific in obstructions of the liver, and justly styled by Dr. Curry, of London, a cholagogue,) given in large doses-say one scruple twice a-day-combined with opium, to cause it to be retained in the system, corrects the condition of the liver by emulging its ducts, unloading its congested or over-gorged vessels, removing undue determinations of blood to its yielding texture, prompting the healthy secretion of its peculiar fluid, and thereby resolves Pyrexia.-As soon as ptyalism takes place, the dysenteric symptoms disappear, and the appetite gradually returns. Upon the whole, my own experience, as well as that of some others who served on this expedition, warrants a far * About the mode of that connection I have indeed speculated pretty freely and pretty largely elsewhere, having employed a good many pages of my Thesis in the discussion of the ratio symptomatum as well as of the ratio causarum-yet I must confess, that the opinions are purely, or at least in a great measure speculative; and that they are not satisfactory, even to my own mind. I shall not further detain the reader in this place, but pass the matter over entirely, resigning to writers of greater native talent, and better inured to habits of difficult investigation, the task of establishing a theory of the disease which shall at once be rational, and shall satisfactorily explain all the phenomena. I may, however, be permitted to hint that no hypothesis which has simplicity for its basis will ever explain this disease: unquestionably Dr. Johnson's leading idea is a most valuable one, viz. that in our investigations of this malady we must seek its source not in one morbid cause, but in a series of morbid causes. I wish it to be distinctly understood that it is my inability alone that induces me not to attempt the theory of this disease; for I shall never fall in with that tone of affected contempt for all theories, in which presumptuous dulness so often shelters its imbecility, and vapid indolence so often masks its habitual and insuperable torpor. Such ill-bestowed contempt may be sufficiently reproved by simply stating the undeniable fact, that not only in medical, but in every other branch of natural and experimental science, few brilliant discoveries have been made except by those acute and industrious men who were labouring to establish some darling hypothesis. Though they were often disappointed of the results they had in view, still they were generally compensated by the discovery of something equally or more valuable;--just as the peasant who was told to dig for hidden treasure, though disappointed of the prize he expected, derived a more rich and permanent treasure, from the digging and fertilizing of the land during his vain search. more certain expectation from this mode of treatment than from the alternation of purgatives with astringents, or any other heretofore in use. I must here observe, however, that I by no means go the length of saying that dysentery in our own climate always requires the excitement of ptyalism by mercury for its cure; because with us it is almost always a slight disease, and compared with the fell and fatal form of tropical flux, might be termed the " spurious dysentery." In ordinary cases, therefore, to push mercury the whole length of salivation, would be merely substituting one ailment, and that perhaps a more troublesome one, for another less so: (for let it ever be remembered that ptyalism is not without its inconveniencies, and sometimes not without its dangers, as I myself have seen :) consequently in such instances, if we equalize the circulation by the warm bath, a purgative, and a sudorific or two, we shall generally find the disease yield. Frequent discharges of slimy mucus, attended with tormina, tenesmus, and feverishness, though designated by the general name of dysentery, are, in this country, often dependent merely on aërial vicissitudes and consequent suppression of the cuticular discharge, and differ widely both in their cause and character from the true dysentery of warmer, but less salubrious regions. But even in this climate, I contend, the principles of cure here laid down will apply with utility, and that in cases which resist the more ordinary treatment, calomel given in larger or smaller doses, (according to circumstances,) will be equally beneficial as within the tropics, provided the patient be always kept in a room whose temperature is between 60 and 70. I have no hesitation in affirming that at New Orleans the success of the treatment by calomel was far greater than that by the usual mode, and I shall here relate a fact which may be regarded as decisive of the rival merits of the two methods of cure. The Cydnus frigate, in which I served, remained in the Gulf of Mexico, after all the rest of our force had retired. From the large expenditure of calomel, I at last had none left, and there was not a grain to be procured. At this time I had several cases of dysentery, which, from necessity, I was obliged to treat, for several days, on the old plan, by neutral salts or oleum ricini alternated with anodyne sudorifics, rhubarb, diluents, mistura cretacea, &c. One case was, indeed, of so bad a type that I had made up my mind for its ending fatally. Luckily, however, our arrival at the Havanna enabled me to procure a supply of good calomel; and I immediately commenced with tengrain doses thrice a-day. Next morning the patient was better; had passed a more tolerable night; had less tormina and tenesmus, and a cleaner tongue. I increased the dose to one scruple night and morning, and thenceforth his improvement was perceptible from day to day. The pyrexia soon abated, and, in ten days, his dejections from being green and foetid, had recovered the natural yellow colour or nearly so. No complaint remained but a sore mouth. This patient, like most of the others, had been very liberally bled at the onset of the disorder. He is now living, (so far as I know,) and is an example of the superior efficacy of this mode of treatment.-The above is merely one of many instances where I have seen calomel work rapidly, and like a charm. To prove with how little apprehension calomel may be given to persons of all ages, I may state that to a boy of 14, one hundred and fifty-two grains were given during the acute stage of a most dangerous attack of dysentery, before his mouth became fairly sore!! He fully recovered. Though mercury had, in this manner, such commanding influence over the disease still experience here was not always uniform, for there were several vexatious instances where it failed. I do not speak of the fatal cases, of which, unhappily we had fifteen, (for in them neither laxatives, astringents, fomentations, blisters, opiates, mercurial frictions on the abdomen, nor calomel pushed to salivation, ever were able to keep off the unhappy event,) but expressly of those few instances where the patients, after being apparently cured, relapsed without any assignable cause, or where ptyalism mitigated the symptoms somewhat-perhaps even suspended the disease entirely until the mouth was well, and then it returned with much of its original violence. The disease thus ran into the chronic form, and harassed the patient for weeks, or even months-with the various symptoms arising from a weak, irritable condition of the primæ viæ, irregular hepatic secretion, and imperfect formation of the chyme. The chief of these symptoms were vomiting after meals, night sweats, febriculæ, watching, arid skin, pains in the lower belly, occasional tenesmus, frequent costiveness, followed by spontaneous diarrhoea and discharges of blood, attended also with frequent prolapsus ani and difficult micturition. In conducting the cure, very delicate management was requisite ; -in fact the disease required rather to be led than driven. A strictly regulated diet, and the use of flannel next the skin, were of the highest consequence. At the same time the patient was put under a gentle and gradual course of calomel, taking three or four grains morning and evening, and rubbing in a portion of mercurial ointment on the belly and right side. Laxatives and astringents were employed occasionally, but, above all, the greatest use was made of opium both internally, and locally per anum, and it really effected most conspicuous benefit. Sulphate of zinc I now and then tried; but from the nausea which it excited, even in three grain pills morning and evening, and from its apparent inefficacy in the disease, I should scarcely, in future, be tempted to give it further trials. The tonic power of Peruvian bark was very useful both as an astringent to the bowels, and as a restorative to the whole system. When the mouth was recovered from the first gentle course of mercury, if the complaint had not yielded, I did not hesitate to use calomel again and again in the same gradual manner, till the gums were repeatedly somewhat affected, and then gave tonics as before. This assiduous perseverance, and the patient attention which it implied, I am happy to say, were well rewarded-many patients were thus recovered from a state--not hopeless indeed-but very precarious, and were re-established in firm health. It is worthy of remark that relapses in this disease are, more than in any other I know, peculiarly frequent and fatal. Most of the deaths occurred in relapsed cases. lu one instance a patient relapsed thrice, and the third was more untractable than the preceding; in him a large abscess sprang up in the epigastric region towards the close of the disease, and burst-discharging profusely bloody and bilious sordes, evincing that the abscess had its radicle in the liver, as dissection afterwards more clearly proved. In two or three instances, the belly, during convalescence, became tumid and tense -and remained thus for a considerable time after their recovery from dysentery. This tumefaction the patients attributed to the state of their liver, and believed themselves to be "Liver-grown," as they expressed it; but from the spontaneous and ofter sudden disappearance of this peculiar symptom, I am rather induced to ascribe the distension to the secretion and extrication of flatus, from the weakened villous coat of the intestines, and from its accumulation in their convolutions and in the cells of the colon. I never had any reason to suspect this disease, or the pyrexia which ushered it in, and attended it, to be in any measure contagious; inasmuch as it did not appear indiscriminately, or spread from man to man by communication; but was entirely confined, both primarily and ultimately, to that portion of the crew whom duty led on shore, or who were employed in the boats on the river Apalachicola. Every boat's crew that returned from such service was sure to bring a reinforcement to the sick list; and out of six new patients thus added, three would be found labouring under ardent fever (for the weather was by this time hot,) and the remaining three under dysentery of the above-described type. From this fact, repeatedly and constantly observed, I am induced to draw the conclusion that both these complaints are excited by one and the same special miasma; for, of a given number of men taken ill in consequence of exposure to the predisposing and exciting causes, it seemed as uncertain as the toss-up of a half-penny whether the one or the other of these diseases would develope itself in an individual or individuals so exposed. This, however, I advance rather as an opinion countenanced by facts, than as being in itself a fact; for I am well aware of the weight of authority that is against me on this point, and must confess that my means of observation have not been sufficiently extensive to warrant a positive induction. PART III. TROPICAL HYGIENE; OR, HINTS FOR THE PRESERVATION OF HEALTH IN ALL HOT CLIMATES. Prestat argento, superatque fulvum As prevention is better than cure, it might seem more natural to have detailed the means of preserving health, before entering on the treatment of diseases themselves. This plan has accordingly been adopted by Dr. Moseley; but I think it an injudicious one. In describing effects, I have traced pretty minutely their causes; and in that way must have obviated a vast tautology in this part of the work. Besides, by exhibiting both causes and effects in one view, I am convinced that the salutary impression is always stronger. For example; could the gravest anathema, denounced with all due solemnity, against sleeping ashore on insalubrious coasts, excite half so much interest in the mind of an European, as the fatal catastrophe at Edam Island? -But another great point is gained by this plan. The various reasonings and remarks which accompanied the treatment and description of diseases, will enable even the general reader to comprehend, with infinitely more ease, the rationale of those prophylactic measures, which I am now to delineate; and which, at every step, will recall to his memory the deplorable effects resulting from a contempt of them. This is no inconsiderable object; for we all know the gratification which springs from understanding what we read. And, in truth, it is a pleasure-nay, it is a positive advantage, to be able to explain, even, on a false theory, the principles of a useful practice. But as theory, in this instance at least, is the legitimate offspring of experience, so, I trust, the superstructure is as firm as the foundation. It has been remarked, by a very competent judge," that by taking the general outline of indigenous customs for our guide, if we err, it will be on the safe side." This is a good rule; but unfortunately it is impracticable-by those, at least, who stand most in need of one. For, before we can become acquainted with these indigenous customs, it will be too late for many of us to adopt them; and could we see them at one coup d'œil, when we first enter a tropical climate, how are we to avail ourselves of them, unless they happen to be in unison with the habits of our countrymen already resident there, who would not fail to sneer at the adoption of any plan which had not the |