The Stokes mss., 1905-1906, consist primarily of letters from Upton Beall Sinclair, 1878-1968, novelist, to James Graham Phelps Stokes, 1872-1960, regarding the activities of the Intercollegiate Socialist Society.
The Howatt mss., 1902-1959, consist in the main of letters to David Howatt, 1882-1964 , farmer and secretary of Upton Beall Sinclair, from writers Harry Kemp, Upton Beall Sinclair, and William James Durant.
The Sinclair mss. IV, 1900-1963, consists of correspondence, writings, and monetary statements of author Upton Beall Sinclair, 1878-1968, and of his wife, Mary Craig (Kimbrough) Sinclair, 1883-1961.
The Trotskii mss., 1900-1957, consist principally of the correspondence of Lev Trotskii, 1879-1940, Russian communist leader, and Max Eastman, 1883-1969, author, during the period when Eastman was preparing his book about Trotskii in 1922 and 1923 and later when he served unofficially as Trotskii's literary agent from 1929 to 1933.
The Rogers, H.M. mss., 1895-1930, consist of letters from Booth Tarkington, 1869-1946, author, to Herbert Milton Rogers, 1870?-1931, lawyer, of Omaha, Nebraska, and former classmate of Tarkington at Princeton University.