Geologist, mathematician, engineer, and physicist. Correspondence, diaries, letterbooks, notebooks, notes, memoranda, maps, charts, tables, landscape sketches, and printed matter primarily relating to Becker's service at the United States Geological Survey, Carnegie Institution of Washington, and as president of the Geological Society of America.

Agriculturist and parasitologist. Correspondence, diary, family papers, biographical and genealogical material, notes, speeches and writings, clippings, scrapbook, printed matter, and miscellaneous material chiefly relating to Curtice’s research into animal diseases.

Astronomer, mathematician, and economist. Correspondence, diaries, commonplace books, drafts of speeches, articles, reviews, and books, financial papers, genealogical papers, charts, tables, computations, photos, and printed matter reflecting Newcomb's personal and family life, his work in mathematics and astronomy, his writing of articles for encyclopedias and other publications, and his work as president of the International Congress of Arts and Sciences.