Apoplexy and palsy have considerably diminished in our city. It is true, the bills of mortality still record a number of deaths from the former, every year; but this statement is incorrect, if it mean a disease of the brain only, for sudden deaths from all their causes are returned exclusively under the name of apoplexy. The less frequent occurrence of this disease, also of palsy, is probably occasioned by the less consumption of animal food, and of distilled and fermented liquors, by that class of citizens who are most subject to them, than in former years. Perhaps the round hat, and the general use of umbrellas, may have contributed to lessen those diseases of the brain. The dropsy is now a rare disease, and seldom seen even in our hospital. The colica pictonum, or dry gripes, is scarcely known in Philadelphia. I have ascribed this to the use of flannel next to the skin as a part of dress, and to the general disuse of punch as a common drink. The natural small-pox is nearly extirpated, and the puerperile fever is rarely met with in Philadelphia. The scrophula is much less frequent than in former years. It is confined chiefly to persons in humble life. I proceed, in the order that was proposed, to take notice of the present medical opinions which prevail among the physicians of Philadelphia. The system of Dr. Boerhaave long ago ceased to regulate the practice of physic. It was succeeded by the system of Dr. Cullen. In the year 1790, Dr. Brown's system of medicine was introduced and taught by Dr. Gibbon. It captivated a few young men for a while, but it soon fell into disrepute. Perhaps the high-toned diseases of our city exposed the fallacy and danger of the remedies inculcated by it, and afforded it a shorter life than it has had in many other countries. In the year 1790, the author of this inquiry promulgated some new principles in medicine, suggested by the peculiar phænomena of the diseases of the United States. These principles have been so much enlarged and improved by the successive observations and reasonings of many gentlemen in all the states, as to form an American system of medicine. This system rejects the nosological arrangement of diseases, and places all their numerous forms in morbid excitement, induced by irritants acting upon previous debility. It rejects, likewise, all prescriptions for the names of diseases, and, by directing their applications wholly to the forming and fluctuating states of diseases, and the system, derives from a few active medicines all the advantages which have been in vain expected from the numerous articles which compose European treatises upon the materia medica. This system has been adopted by a part of the physicians of Philadelphia, but a respectable number of them are still attached to the system of Dr. Cullen.