The records document the establishment and administration of the Boyden Station, astronomical and meteorological research activities undertaken at the station, and travel and life in the late nineteenth and early twentieth century Peru. The weekly correspondence in this collection between the director of the Harvard College Observatory in Cambridge and the director of the Boyden Station in Peru, documents virtually every reportable aspect of research and study carried out at the Station. In addition this collection contains Solon I. Bailey's journals and notebooks describing his expeditions to establish an observatory in both South America and later in South Africa. The records contain letterpress books, journals, notebooks, invoices, postcards, telegrams, lists, sketches, and photographs.