PENNOCK, Casper Wistar, physician, born in Philadelphia, Pennsylvania, 2 July, 1799; died in Howellsville, Chester County, Pennsylvania, 16 April, 1867. He became a farmer, and opened an evening-school for negroes in his neighborhood, teaching it himself after the labors of the day. He then entered on the study of medicine at the University of Pennsylvania, and after graduation in 1828 spent some time in the almshouse hospital, and then went to Paris, where he remained for two years. In 1835 he became an attending physician at the Philadelphia hospital, where he and Dr. William W. Gerhard, his colleague, studied the symptoms and pathological anatomy of typhus fever. The results of their joint study, which were published by Dr. Gerhard, have been of great value. He also entered on a course of investigation on the play of the heart in animals, but soon afterward he was prostrated by disease, and for more than twenty years before his death labored under an unusual form of paralysis. In accordance with directions that he had given some years before his death, a post-mortem was held by several eminent physicians, and a report of the case, the first of the kind that had been noted in this country, by Dr. J. C. Morris, was published in the "Transactions of the College of Physicians of Philadelphia" (4 December, 1867), and afterward translated into French as "Le cas du Docteur W. Pennock, ou contribution 'g l'histoire de la sclerose en plaques disseminees" (Paris, 1868). Dr. Pen-nock published, with Dr. William W. Gerhard. "Observations on the Cholera of Paris " (Philadelphia, 1832), and edited the treatise of Bouillaud on the diseases of the heart (1837) and Dr. James Hope's "Treatise on Disease of the Heart and the Great Vessels" (1846).