This collection is primarily concerned with Prof. James Renwick and his professional correspondence and papers, both as Professor of Natural Philosophy (Physics) at Columbia College and as a leading engineer. Many certificates of membership in honorary societies are included. There are letters from Washington Irving (1783-1859) to Prof. Renwick and to his mother, Jane Jeffrey Renwick, pertaining to contemporary events and Irving's own activities. The letters to Mrs. Renwick are about the travels and experiences of Irving and Renwick abroad. The collection also covers the affairs of the Prof. Renwick's grandfather, including documents concerning his land grants in New York State, and those of James Armstrong Renwick, including his valedictory address at Columbia College in 1876 and his class reunion in 1916. There are many legal documents, letters, and manuscripts of various members of the Renwick and Brevoort families; among these are Prof. Renwick's notes on his family genealogy and a memoir of Jane Jeffrey Renwick. Correspondents include Clement Clarke Moore, John A. Dix, Martin Van Buren, Secretary of State John Forsyth, and Secretary of the Navy James K. Paulding. There is one letter from Sir Edward Sabine (1788-1883), President of the Royal Society, giving his views on the American Civil War.