These records document the establishment and administration of the Boyden Station observatory in Arequipa, Peru, and the astronomical and meteorological research undertaken at the Station, as well as documenting a Committee for the Station, and the Friends of the Station. The weekly correspondence between the director of the Harvard College Observatory in Cambridge and the director of the Boyden Station 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.