The weather was variable during the months of February and March. The navigation of the Delaware was not completely opened until the latter end of February. The diseases of these two months were catarrhs and bilious pleurisies. The former were confined chiefly to children, and were cured by gentle pukes, purges of calomel, and blood-letting. The last remedy was employed twice in a child of Isaac Pisso, of six weeks old, and once in a child of Thomas Billington, of three weeks old, with success. On the 7th of April, I visited Mr. Pollock, lately from the state of Georgia, in consultation with Dr. Physick, in a yellow fever. He died the evening after I saw him, on the third day of his disease. There was a snow storm on the 16th of April, and the weather was afterwards very cold. Such leaves and blossoms as had appeared, were injured by it. On the 1st of May, the mercury in Fahrenheit's thermometer rose to 84°. The weather, during the latter part of this month, and in June, was very dry. On the 6th of June, Dr. Cooper lost a patient in the yellow fever, near the corner of Twelfth and Walnut-streets. Mark Miller died with the same state of fever on the 2d of July. About a dozen cases of a similar nature occurred, under the care of different practitioners, between the 2d and 20th of this month, and all of them in parts of the city remote from Water-street. On the 19th of July, the weather was so cool as to render winter clothes comfortable. A severe hail storm had occurred, a few days before, in the neighbourhood of Wilmington, in the Delaware state. On the 21st of the month, the ship Deborah arrived from one of the West-India islands, and discharged her cargo in the city. She was moored afterwards at Kensington, where the foul air which was emitted from her hold produced several cases of yellow fever, near the shores of that village. In August the disease appeared in nearly every part of the city, and particularly in places where there was the greatest exhalation from foul gutters and common sewers. In describing the disease, as it appeared this year, I shall take notice of its symptoms as they appeared in the blood-vessels, alimentary canal, the tongue, the nervous system, in the eyes, the lymphatic system, and the blood. The subjects which furnished the materials for this history were not only private patients, but the poor in the city hospital, who were committed to the care of Dr. Physick and myself, by the board of health. I. The pulse was, in many cases, less active in the beginning of this fever than in former years. It was seldom preternaturally slow. It resembled the pulse which occurs in the first stage of the common jail fever. Hæmorrhages were common about the fourth and fifth days, and generally from the gums, throat, or stomach.