The collection consists of drawings, correspondence, photographs, documents, a genealogy, financial papers, and printed matter of Denby. The collection contains material for his unpublished books Meandering Way Round the Mediterranean,, Most of Europe and the Near East, and A Treatise on Lettering by Modules; architect's record books, order books, contracts, checkbooks, mortgage receipts, an accountant's report (1938), and ledgers (1906-1923); photographs of buildings designed by the architectural firm of Denby and Nute; architectural drawings for the Yonkers (N.Y.) Public Library and the Mt. Vernon (N.Y.) Public Library; blueprints, architectural renderings, a collection of drawings and rubbings of Romanesque capitals, moldings, and borders; and two notebooks describing Denby's mnemonic system based on a numerical device. There is also Denby family material including the journal (1863) of Denby's father, Edwin Robinson Denby, medical officer on the Wyoming in the Straits of Sunda, containing comments about the progress of the Civil War; a report by Dr. Denby about the sanitary conditions aboard the Lancaster (1875), with a scrapbook kept by his wife, Laura Hooper Denby, regarding Dr. Denby's death from yellow fever and the outbreak of the disease among the sailors; a traveler's diary (1870) by Mrs. Denby; and a penmanship style book (1823) by Emma Woodridge.