Finding aids (59) Images (38)

Archival materials (64) Collection descriptions (59) Photographs (24) Correspondence (13) Manuscripts (13) Drawings (12) Ephemera (11) Business ephemera (10) Clippings (10) Reports (10) Advertisements (9) Black-and-white photographs (8) Trade literature (8) Blueprints (7) Business records (7) Catalogs (7) Legal documents (7) Patents (7) Publications (7) Motion pictures (visual works) (6) Photograph albums (6) Annual reports (5) Black-and-white negatives (5) Brochures (5) Color photographs (5) Commercial catalogs (5) Financial records (5) Newsletters (5) Notebooks (5) Sales records (5) Scrapbooks (5)

Railroads (8) Bridges (5) Patents (5) advertising (5) Aeronautics (4) Manufacturing (4) Piano makers (4) World War, 1939-1945 (4) Buildings (3) Consumer goods (3) Dams (3) Factories (3) Hydraulic engineering (3) Museum exhibits (3) Piano (3) Pneumatics (3) Railroad bridges (3) Tunnels (3) Aeronautics, Military (2) Architects (2) Architectural design (2) Bridge construction industry (2) Canals (2) Chemistry (2) Civil engineering (2) Civil engineers (2) Committees (2) Company towns (2) Concrete (2) Concrete construction (2) Congresses and conventions (2)

Warshaw, Isadore (10) National Museum of American History (U.S.). Division of Mechanical and Civil Engineering (7) National Museum of American History (U.S.). Division of History of Technology (6) National Museum of American History (U.S.). Division of Work and Industry (5) Langley, S. P. (Samuel Pierpont) (3) Gray Instrument Company (2) Leeds and Northrup Company (2) National Air and Space Museum. Archives Division. (2) Pratt, Read and Company (2) Princeton University (2) Queen, James W., & Company (2) Queen-Gray Company (2) Watkins, J. Elfreth (John Elfreth) (2) Adams Express Company (1) All-American Mohawk Company (1) American Academy of Environmental Engineers. (1) American Association for the Advancement of Science (1) American Petroleum Institute. (1) American Railway Express Agency (1) American Telephone and Telegraph Company (1) Ames Manufacturing Company (1) Amoskeag Manufacturing Company. (1) Apollo Piano Company (1) Arthur Lodge Productions. (1) Atlantic Cotton Mills (1) Ayer (N W) Incorporated. (1) Ayer, Francis Wayland (1) Baring Brothers Company (1) Beach-Carlisle Violin Company (1) Boston and Lowell Railroad Corporation (1) Boston and Roxbury Mill Corporation (1)

Ivoryton (Conn.) (2) New York (N.Y.) (2) Pennsylvania (2) Africa (1) Baltimore (Md.) (1) Benin (1) Beverly (Mass.) (1) Boston (Mass.) (1) Brandon (Vt.) (1) Brookline (Mass.) (1) Burkina Faso (1) Central African Republic (1) Charlestown (Boston, Mass.) (1) Chesapeake and Ohio Canal (1) Cincinnati (Ohio) (1) Congo (Democratic Republic) (1) Corinth (Miss.) (1) Côte d'Ivoire (1) DeKalb (Ill.) (1) Egypt (1) Foxborough (Mass. : Town) (1) France (1) Georgetown (Washington, D.C.) (1) Ghana (1) Great Britain (1) Harrisburg (Penn.) (1) Hudson River (1) Hudson River Tunnel (1) Janesville (Wis.) (1) Kanawha River Canal (1) Kenya (1)

Archives Center, National Museum of American History (42) Smithsonian Institution Archives (12) National Air and Space Museum Archives (9) Eliot Elisofon Photographic Archives, National Museum of African Art (1)