​SCHWARTZ, Jacob, librarian, b. in New York city, 13 March, 1846. In 1863 he entered the Apprentices' library of New York, of which he became chief librarian in 1871. He has introduced in the institution his system of classification, which has since been adopted wholly or in part by various librarians. This system is a combination of the three fundamental systems—the classified, the alphabetical, and the numerical. The method of management that is followed there was also devised by him. Mr. Schwartz has contributed to the “Library Journal” and other periodicals.