The papers document the professional career of mechanical engineer, Charles Richardson Pratt. The papers include correspondence, patents, patent application materials, agreements, photographs, publications, and blueprints for many of Pratt's inventions, especially his work on elevators.
Scope and Contents:
These papers contain personal materials of Charles R. Pratt; letterpress copybooks; engineering notebooks; diaries; material relating to the development of the heavy-duty, high-rise electric elevator; material concerning elevator cable equalizers and safety devices, Morton-Jacobsen and other lathe chucks, lathe drives and the Pratt Driver, the hydraulic transmission of power in trucks, and ship steering gear; and studies reports, drawings, photographs, catalogs, and trade literature concerning mechanical engineering.
The collection is arranged into eight series.
Series 1: Personal Materials, 1875-1935
Series 2: Diaries, 1894, 1928-1931
Series 3: Correspondence, 1872-1920
Series 4: Notebooks, 1880, 1889, 1900
Series 5: Inventions, 1860-1927
Series 6: Photographs, 1890-1902
Series 7: Publications, 1895-1929
Series 8: Drawings, 1878-1929
Biographical / Historical:
Charles Richardson Pratt (1860-1935), was born in Massachusetts to John C. and Mary Anne Richardson. He graduated from the Hopkins School of Boston and the Massachusetts Institute of Technology in 1879. Pratt worked at Whittier Machine Company of Boston (1882-1890) where he designed and built the first electric elevator in 1888. The elevator was installed in the Tremont House, Boston. Pratt also worked as an agent and later as a consulting engineer for the Otis Elevator Company, the inventors of the hydraulic elevator.
Pratt was best known for his development of the first electrically powered elevator. In 1892, inventor Frank Sprague (1857-1934) founded the Sprague Electric Elevator Company, and with Charles R. Pratt developed the Sprague-Pratt Electric Elevator. They demonstrated that electrically powered elevators were capable of competing with hydraulic elevators. Pratt held several engineering positions and worked for the Marine Engine Company of Newark, New Jersey (1902-1905) developing elevator systems; consulting engineer to the Universal Speed Control Company of New York City (1906-1919); consultant to the American Engineering Company of Philadelphia (1912); mechanical superintendent at the Crocker Wheel Company of Ampere, New Jersey (1919); engineer for the E. Horton and Sons Company of Connecticut (1920-1923); the General Tractors Corporation (1924-1927); and was associated with the Watson Elevator Company of New York City (1928-1930). Pratt patented many of his ideas, earning over thirty-five patents related mostly to elevators,
Pratt was a member of the Masons, the Sons of the American Revolution, the American Society of Mechanical Engineers, the MIT Club of New Jersey, and the Motor Club of London. He married Mary Byron Ladd and they had two children, Gertrude Ladd Pratt and Donald Richardson Pratt.
This collection was purchased from Charles R. Pratt's daughter, Gertrude Pratt Vance, in 1973.
Collection is open for research.
Collection items available for reproduction, but the Archives Center makes no guarantees concerning copyright restrictions. Other intellectual property rights may apply. Archives Center cost-recovery and use fees may apply when requesting reproductions.