"This collection contains all of the society's anti-slavery materials, including tracts, miscellaneous pamphlets, and other ephemeral documents, and some rare, early periodicals of the Thompson-Clarkson Collection, on which Thomas Clarkson based his 'History of the Abolition of Slavery'. It also contains items from the typescript 'Chronological Bibliography of Anti-Slavery Tracts,' based on materials found in several British libraries"--The Library of Congress Guide to the Microform Collections in the Humanities and Social Sciences Division, online version.