From the variety and importance of its therapeutic effects, oil of turpentine deserves to rank among the most valuable medicines. In regard to some of these effects, the anthelmintic, namely, the rubefacient, and those exerted on the urinary organs, it will be considered elsewhere. In this place, it is to be treated of mainly as a stimulant, either generally to the system, or locally to the alimentary mucous membrane.

Gold Stage of Fevers. In consequence of the absence of any direct effect on the brain, at least in ordinary stimulant doses, the oil may be given in all instances of depression or collapse, occurring in the cold stage of febrile diseases, when internal stimulation is required. In some cases of this kind, I have known it to be very useful; and it may be given with great freedom.

Low Fevers generally. It has also been considerably used as a stimulant in low states of fever, especially when the existence of disorder of the brain may be supposed to contraindicate the alcoholic liquors, and other cerebral stimulants. In typhus and typhoid fevers it has long been employed with this view; and I found it in use upon entering into the practice of medicine, nearly fifty years ago. But it was given only as a stimulant, and, though successful in some instances, appeared in others to display little remedial power. I claim to have discovered the principle upon which its special success in these cases depended, or at least the precise circumstances under which it proved successful; so that its employment may now be regulated with considerable confidence of gaining the results aimed at. As a mere stimulant, it may be employed in most instances of low fever, but must take rank with others of the class, and indeed below several of them. In regard to the special object which I now have in view, it can be replaced, so far as I know, with equal benefit, by no other medicine.

The advanced stage of the fever named specifically typhoid fever, but for which I have ventured to propose the name of enteric fever, affords the condition here referred to. I may, perhaps, be excused if I relate the circumstances which led me to this discovery; as I shall thus be able to produce a stronger impression on the reader than by a mere abstract statement of results. In the year 1823, I had under my care a case of fever of the kind then known as nervous fever, or slow remittent, or typhus mitior, by which titles it was variably and somewhat indefinitely called, in the advanced stage of which, violent peritoneal inflammation came on, ending speedily in death. On examination, I found a number of ulcerated surfaces in the mucous membrane of the ileum, in one of which, near the caecum, a large perforation existed, through which a portion of the contents of the bowels had passed into the peritoneal cavity. In this case there had been tympanitic abdomen, and the tongue, after having parted with a portion of the fur in the centre, leaving a smooth moist red surface, had suddenly ceased to advance in the cleaning process, and become quite dry before the occurrence of the perforation. Not long previously to this, I had witnessed a fatal case in the practice of a friend, which, after an abortive attempt to clear the tongue in a similar manner, with a similar dryness afterwards, had become aggravated, and ended fatally. Comparing these cases, I was induced to think that the peculiar condition of the tongue referred to, with the tympanitic abdomen, might be the result of the ulceration of the ileum, and that, if I could find a medicine which would correct this ulcerative condition, I might possibly in future save my patients under similar circumstances. Not long afterwards another case presented itself, having the same distinctive characters. Terebinthinate remedies having been found useful in ulcerative affections of the bowels, it occurred to me that the oil of turpentine might possibly answer my purpose in this instance. I gave it accordingly. In twenty-four hours, the tongue showed a disposition again to become moist, a little white fur began to appear on the part before denuded, there was an amelioration of the other symptoms, and from that time the inarch towards health was uninterrupted under the continued use of the remedy, though I had in the beginning almost despaired of my patient. Other cases occurred afterwards, of the same character, and with the same results; and from that time to the present, though I have seen great numbers in toy private practice, in consultation, and in the Pennsylvania Hospital, I have lost only two, presenting the phenomena mentioned. Of these two, one exhibited, on examination after death, such an amount of disease in the ileum as to have rendered a fatal issue unavoidable; and in the other, a small ulcerated opening was found at the bottom of an offset of the bowel, or cul-de-sac. about an inch and a half in depth, into which, as it was filled with mucus, the oil had been unable to penetrate, so as to come into contact with the surface of the ulcer; while several large ulcerated patches in the ileum were rapidly cicatrizing, showing the probably beneficial influence of the remedy on them. A brief account of the use of the oil in this condition of febrile disease, and of the circumstances which led to it, was published in the North American Medical and Surgical Journal for April, 1826 (page 272). When the admirable work of Louis on typhoid fever appeared. I at once recognized, in his description, the disease which had exhibited the phenomena above mentioned. The ulcerative condition referred to, I had previously considered as liable to occur in any protracted liver. 1 now learned that it was the characteristic lesion of a special disease. My therapeutic views, therefore, were immediately transferred to the typhoid fever, which Louis had enabled us accurately to diagnosticate, and, having tried the remedy in this affection, J found my best hopes fulfilled. Ever since that time, I have been in the habit, in my lectures in the University of Pennsylvania, of strenuously recommending the oil of turpentine in the treatment of enteric or typhoid fever, and have done the same in my work on the Practice of Medicine, always restricting its use to the period of probable softening and ulceration in the diseased glandular patches, and expressing my belief that it was no specific in that disease, but might be confidently relied on as having a favourable influence over this peculiar morbid affection of the bowel, and vastly diminishing the danger from that source. Abundant testimony has been given to me, by practitioners from various parts of the Union, of very favourable changes having taken place in the mortality of the disease, after they had adopted the practice here recommended. It will be best, probably, after this brief history, that I should state distinctly, the condition under which, in enteric fever, the oil may be beneficially employed, and the principles upon which I believe it to act.