I derived great pleasure from hearing, after the fever had left the city, that calomel had been given with success as a purge in bilious fevers in other parts of the union besides Philadelphia. Dr. Lawrence informed me that he had cured many patients by it of the yellow fever which prevailed in New-York, in the year 1791, and the New-York papers have told us that several practitioners had been in the habit of giving it in the autumnal fevers, with great success, in the western parts of that state. They had probably learned the use of it from Dr. Young, who formerly practised in that part of the United States, and who lost no opportunity of making its praises public wherever he went. I have only to add to my account of that purging medicine, that, under an expectation that the yellow fever would mingle some of its bilious symptoms with the common inflammatory fevers of the winter and first spring months, I gave that purge in the form of pills, in every case of inflammatory fever to which I was called. The fatal issue of several fevers in the city, during the winter, in which this precaution had been neglected, convinced me that my practice was proper and useful. It is to be lamented that all new remedies are forced to pass through a fiery ordeal. Opium and bark were long the objects of terror and invective in the schools of medicine. They were administered only by physicians for many years, and that too with all the solemnity of a religious ceremony. This error, with respect to those medicines, has at last passed away. It will, I hope, soon be succeeded by a time when the prejudices against _ten_ and _ten_, or _ten_ and _fifteen_, will sleep with the vulgar fears which were formerly entertained of the bark producing diseases and death, years after it had been taken, by "lying in the bones." OF BLOOD-LETTING. The theory of this fever which led me to administer purges, determined me to use blood-letting, as soon as it should be indicated. I am disposed to believe that I was tardy in the use of this remedy, and I shall long regret the loss of three patients, who might probably have been saved by it. I cannot blame myself for not having used it earlier, for the immense number of patients which poured in upon me, in the first week of September, prevented my attending so much to each of them, as was necessary to determine upon the propriety of this evacuation. I was in the situation of a surgeon in a battle, who runs to every call, and only stays long enough with each soldier to stop the bleeding of his wound, while the increase of the wounded, and the unexpected length of the battle, leave his original patients to suffer from the want of more suitable dressings. The reasons which determined me to bleed were, 1. The state of the pulse, which became more tense, in proportion as the weather became cool.