7th. In respect to the duration of the two diseases, we may state as a general rule, that yellow fever runs its course to death or convalescence, in a much shorter time than bilious fever. Nor is the promptness of recovery from yellow fever less different from the slowness of convalescence, noticed in most cases of bilious fever. 8th. The suppression of urine is a frequent attendant on the last stage of yellow fever, and is seldom noticed in bilious fever. 9th. I have never witnessed a second attack of yellow fever in the same individual; whilst on the contrary, so far as I have seen, there is no limitation to the number of times a person may be affected with the other form of fever. _Prognosis._--As regards the prognosis in yellow fever, I shall merely state, that I generally found, an early evacuation from the alimentary canal, and a disposition to diaphoresis during the first twenty-four or thirty-six hours, and its continuance during the course of the disease, to be favourable omens. When the disease continued beyond the 7th, 9th, or 11th day, greater hopes might be entertained. It was likewise found, that the mortality was much smaller among patients, who remained free from apprehensions as to the nature and termination of the disease. To this cause, more than any other, do I refer my greater success among Quakers; who, being generally surrounded and comforted by their friends, retained more than any other class of people, the necessary tranquillity of mind. Among the unfavourable signs may be mentioned, a discoloration of the skin before the fourth day. This symptom was, indeed, almost always a fatal one. Obstinate vomiting and costiveness, haemorrhages from different parts of the body, unattended with an abatement of the symptoms, and vomiting of black matter, were very unfavourable; whilst a suppression of urine, agreeably to my experience, was always a fatal sign.