The collection consists of correspondence, notes, memoranda, extracts from publications, reprints, drafts of essays, poems, magazine and newspaper articles, comic strips, popular songs, and other material on bioluminescence, collected principally between 1945-1959 for his History of Luminescence from the Earliest Times until 1900 (American Philosophical Society Memoirs 44, 1957). Other topics are chemistry, military medicine, natural history, and professional associations.