I seldom derived much advantage from the use of tonics and stimuli in yellow fever; except when the powers of life seemed to fail, and petechiae, vibices, haemorrhages, and other signs of malignancy had occurred. In general, under such circumstances, the Peruvian bark, either alone or combined with serpentaria, was administered in preference to any other remedy of the same class. In cases, however, unattended with reaction, tonics and diffusible stimuli internally, and revulsives of all sorts externally, were had recourse to from the commencement of the attack, and sometimes with the desired effect of arousing the powers of the system. _Opium_ was never found beneficial, on account of its tendency to aggravate or produce coma, as well as from its effect in suppressing intestinal evacuations. Whilst making use of the above remedies, the plentiful exhibition of diluent drinks was not neglected,--care being taken, however, not to load unduly the stomach, and to select such drinks as would suit the taste of the patient. In almost every case, acids did not answer so well as the bland mucilaginous infusions. The drinks were almost universally allowed cold, except when there existed a tendency to perspiration; under which circumstances they were administered slightly warm and a little aromatic. During the course of the yellow fever, some of the symptoms demanded particular attention. Influenced by the idea of prostration and dissolution, many practitioners, and myself for some time among the rest, resorted to the bark and other tonics for the purpose of arresting the black vomit, and of correcting that condition of the organs, which gave rise to this effusion; but after many unsuccessful trials, I was led to abandon this practice and to resort to other means. Of all the remedies employed to attain this effect, calcined magnesia mixed in a thick solution of gum arabic seemed to me to answer best; for whilst it succeeded, in many cases, in arresting the vomiting, it tended to keep the bowels open. Together with this, revulsive remedies were applied to the skin, and sometimes succeeded very well,--a sufficient proof, I think, that this haemorrhage is the effect of an increased action of the mucous membrane of the digestive tube, and not of a passive condition of the capillaries of the parts. For the purpose of controlling the great irritability of the stomach, and arresting the vomiting occurring in the early stage of the disease, besides the usual remedies used in such cases, I found advantage in the use of small and frequently repeated injections with a solution of salts, an infusion of senna, or the like substances. Such a practice, however, did not seem to succeed so well in the latter stage of the disease.