I recollect having more than once perceived a smell which had been familiar to me during the prevalence of the yellow fever in 1793. It resembled the smell of liver of sulphur. I suspected for a while that it arose from the exhalations of the gutters of the city. But an accident taught me that it was produced by the perspiration of my body. Upon rubbing my hands, this odour was increased so as to become not only more perceptible to myself, but in the most sensible degree to my pupil, Mr. Otto. From this fact, I was convinced that I was strongly impregnated with miasmata, and I was led by it to live chiefly upon vegetables, to drink no wine, and to avoid, with double care, all the usual exciting causes of fever. There was another mark by which I distinguished the presence of the seeds of this fever in my system, and that was, wine imparted a burning sensation to my tongue and throat, such as is felt after it has been taken in excess, or in the beginning of a fever. Several persons, who were exposed to the miasmata, informed me that wine, even in the smallest quantity, affected them exactly in the same manner. I attended four persons in this fever who had had it the year before. It remains now that I mention the origin of this fever. This was very evident. It was produced by the exhalations from the gutters, and the stagnating ponds of water in the neighbourhood of the city. Where there was most exhalation, there were most persons affected by the fever. Hence the poor people, who generally live in the neighbourhood of the ponds in the suburbs, were the greatest sufferers by it. Four persons had the fever in Spruce, between Fourth and Fifth-streets, in which part of the city the smell from the gutters was extremely offensive every evening. In Water-street, between Market and Walnut-streets, many persons had the fever: now the filth of that confined part of the city is well known to every citizen. I have before remarked, that one reason why most of our physicians refused to admit the presence of the yellow fever in the city, was because they could not fix upon a vestige of its being imported. On the 25th of August, the brig Commerce arrived in the river, from St. Mark, commanded by Captain Shirtliff. After lying five days at the fort, she came up to the city. A boy, who had been shut out from his lodgings, went, in a state of intoxication, and slept on her deck, exposed to the night air, in consequence of which the fever was excited in him. This event gave occasion, for a few days, to a report that the disease was imported, and several of the physicians, who had neglected to attend to all the circumstances that have been stated, admitted the yellow fever to be in town. An investigation of this supposed origin of the disease soon discovered that it had no foundation. At the time of the arrival of this ship, I had attended nearly thirty persons with the fever, and upwards of a hundred had had it, under the care of other physicians.