Records prior to 1907 consist mostly of incoming correspondence (outgoing correspondence can be found in record unit 112). After 1907 the records contain both incoming and outgoing correspondence. Much of the material consists of routine public inquiries. In addition, these records document museum accessions and Smithsonian expeditions and field trips. Other topics include Smithsonian participation in expositions, operation of certain museum divisions, and miscellaneous subjects. Accession records include: data on the Herber R. Bishop jade collection; William Joseph Hammer collection of incandescent lamps, 1905; Robert Ward collection of ferns, 1905-1906; transfer of the United States Patent Office collections to the United States National Museum, 1906-1909; Hubert G. Squires collection of Chinese porcelain; Hippisley collection of Chinese porcelain, 1909-1912; collections from the Arizona fossil forest; E. A. Wakefield collection of Basuto pottery; James D. S. Chalmers collection of minerals; McIntire collection of historical objects; Charles Fuller Baker collection from the Galapagos Islands; United States National Museum collection of postage stamps; Isaac Lea collection of gems and mollusks; George D. Seymour collection of clocks; Joseph Priestley collection of scientific apparatus; Robert C. Hall ethnological collection; Dwight J. Partello bequest; John B. Bernadou bequest; Bernard Rogan Ross ethnological collections; Mrs. James W. Pinchot collection of textiles; Richard Mansfield collection of theatrical costumes; B. F. Chandler herbarium; Morris Loeb collection of chemical compounds; Donn collection of Lincoln relics; Frank S. Collins herbarium and library; Oldroyd collection of Lincoln relics; Thomas Jefferson writing desk; Richard E. Byrd airplane "Josephine Ford"; Walter W. Holmes fossil bird bone collection; Brush-Swan electrical apparatus collection; collection of first ladies' gowns in the United States National Museum; Virgil Michael Brand coin collection; Charles Russell Orcutt natural history collections; Isobel H. Lenman collection of Old World archaeology; American period costume collection in the United States National Museum; Charles A. Lindbergh collection of personal memorabilia; Nordenskold Mesa Verde collection; Joseph Nelson Rose collection of cacti; Osborne collection of Guatemalan textiles; United States National Museum collection of building stones; the Holt collection of birds from South America, 1936-1940; the Annie H. Hegeman lace and textile collection; the United States National Museum's collection of Jean Leon Gerome Ferris paintings; James Townsend Russell anthropological collection; the Harvey Harlow Nininger meteorite collection; the Hope diamond.
Records related to Smithsonian expeditions and field work include: Mexican-United States Boundary Commission; expeditions and collecting in the Philippine Islands, 1903-1905; University of Pennsylvania expedition to Babylonia, 1887-1888; Metropolitan Museum of Art Expedition to Egypt, 1909; Arthur deC. Sowerby collecting trips to China, 1909-1936; Owen Bryant-William Palmer expedition to Java, 1905-1910; Smithsonian-Roosevelt African expedition, 1909; Rainey African expedition, 1911; Smithsonian-Harvard expedition to Altai Mountains, Siberia, 1912; National Geographic Society-Yale University expedition to Peru, 1915; Smithsonian-Universal Film Manufacturing Company African Expedition, 1920; David C. Graham collecting work in China, 1925-1940; Hugh McCormick Smith collecting work in Siam; Marsh-Darien expedition, 1924; Smithsonian biological survey of the Panama Canal Zone, 1911-1912; Ellsworth Paine Killip collecting work in Europe, 1935, and Venezuela, 1943-1944; Henry Bascom Collins, Jr., field work in Mississippi and Louisiana, 1938; Herbert Girton Deignan's collecting work in Siam, 1936-1937; the Johnson-Smithsonian Deep Sea Expedition to the West Indies, 1933; Stanley John's collecting work in the British West Indies, 1935-1938; Charles W. Gilmore and Frank H. H. Roberts collecting work in Arizona, 1937; the National Geographic Society-Smithsonian Institution Archeological Expedition to Vera Cruz, Mexico, 1938-1939; Matthew William Stirling's field work in Mexico, 1940-1946; the National Geographic Society-University of Virginia Expedition to the South Pacific Islands, 1939; Walter W. Taylor, Jr.'s, archeological field work in Mexico, 1940-1945; Floyd A. McClure's bamboo investigations in Mexico and Central and South America, 1943-1944; Henri Pittier's botanical field work in Venezuela, 1944-1946; Philip Hershkovitz field work in Colombia, 1946-1950; the Finn Ronne Antarctic Research Expedition, 1946-1948; Brina Kessel field work in Alaska, 1950; Clifford Evans, Jr., field work in Ecuador, 1954-1958; Marshall T. Newman field work in Peru, 1955-1957; James Paul Chapin collecting work in Africa, 1957; Ralph S. Solecki field work in Iraq, 1954-1959.
Records that document Smithsonian involvement in expositions include: South Carolina and West Indian Exposition, Charleston, 1902; Louisiana Purchase Exposition, St. Louis, 1904; Jamestown (Virginia) Tercentenary Exposition, 1907; International Photographic Exposition, Dresden, 1909; World's Columbian Exposition, 1896; Panama-California Exposition, San Diego, 1915; Panama-Pacific International Exposition, San Francisco, 1915; International Silk Exposition, New York, 1921; Pageant of Progress Exposition, Chicago, 1922; Sesquicentennial Exposition, Philadelphia, 1926; Progress Exposition, New Haven, 1926; International Exposition, Seville, Spain, 1927; Century of Progress Exposition, Chicago, 1931; Great Lakes Exposition, Cleveland, 1936; New York World's Fair, 1939; Golden Gate International Exposition, San Francisco, 1939; Texas Centennial Exposition, Dallas, 1936; Greater Texas and Pan American Exposition, 1937; Port-au-Prince Bicentennial Exposition, Haiti, 1949.
Records related to the origin or operation of subdivisions of the United States National Museum include: development of the Division of Textiles; history of the National Herbarium, 1886-1908; development of the Division of Medicine; development of the Division of Mineral Technology, 1914; Traveling Exhibit Service; Division of Graphic Arts; Division of Numismatics.
Miscellaneous topics covered by these records include: establishment of Bermuda Biological Station, 1900-1904; United States military operations against insurgents in the Philippine Islands, 1904; the Lincoln Memorial Commission, 1913; proposed construction of a George Washington Memorial; National Museum involvement in search for the Port Orford meteorite; exhibition of the "Spirit of St. Louis"; National Museum exhibition of objects from World War I; use of the National Museum Building by the Bureau of War Risk Insurance in World War I; proposed creation of a National Museum of Engineering and Industry under Smithsonian control; Samuel P. Langley's aerodrome experiments; Smithsonian activities during World War II, particularly the evacuation of United States National Museum collections from Washington; A. Remington Kellogg's work on the Governmental Advisory Committee on Oceanography and the International Whaling Commission; United States National Museum correspondence with Phineas T. Barnum, 1882-1891; Washington A. Roebling's mineral collections.
Most of the correspondence is directed to the officer in immediate charge of the United States National Museum (Richard Rathbun, 1897-1918; William deC. Ravenel, 1918-1925; Alexander Wetmore, 1925-1948; A. Remington Kellogg, 1948-1962) with lesser amounts to John Enos Graf, who was appointed Associate Director, United States National Museum, in 1931. Also, a smaller amount of correspondence is addressed to the Secretary of the Smithsonian (Spencer F. Baird, 1878-1887; Samuel P. Langley, 1887-1906; Charles D. Walcott, 1907-1927; Charles G. Abbot, 1928-1944; Alexander Wetmore, 1944-1952; Leonard Carmichael, 1953-1964) and to various museum curators. This correspondence was usually referred to the chief administrator of the United States National Museum for response.