Correspondence, manuscripts, photographs, and printed materials of Lamont. Letters from George Santayana (1863-1952), with Lamont and others, a few early manuscripts, interviews and other notes on Santayana, and general correspondence about him. A series of letters from John Dewey to Lamont, discussing his ideas on humanism and religion. Extensive correspondence with the family of John Masefield including approximately 100 letters from Judith Masefield to Lamont, primarily written shortly after the death in 1967 of her father the poet John Masefield, and dealing with his life and work. Also, a few of her own writings; a number of the letters are descriptive of historical England and her concern for contemporary events. Among the letters from other family members are fifteen from Lamont's nephew, Jack Masefield, and 53 from his cousin Sir Peter G. Masefield, 1970-1983, conveying news about Judith as well as interest in the publication of John Masefield's letters from the World War I years and their continuing appreciation of Lamont's work on Masefield. There is discussion on the publication of Masefield's letters to Corliss' mother, Florence Lamont, printed in 1979.

Twenty-one letters from Ella Winter to Lamont were written in America and England between 1940 and 1976. World War II letters express concern for help to our Soviet Allies. Later letters concern the Bridges case and civil liberties in the McCarthy era, and the Vietnam War and its impact on Britain.

Thirty three letters between Sir Julian Huxley and Lamont, 1927-1974, have been added, as well as photostats of letters from Gen. J.C. Smuts to Florence C. Lamont and manuscripts of Lucy Lamont Gavit.