Prototype for Willis Two-Wheeled Planimeter
date: label: date made
content: 1922-1941
name: label: maker
content: Willis, Edward Jones
notes: label: Description
content: Even after the apparent commercial success of his "improved planimeter," Edward Jones Willis (1866–1941), a steam and electrical engineer from Richmond, Va., continued to experiment with planimeter designs. On January 17, 1922, he received a patent for a planimeter that had the measuring wheel on a spindle instead of a wheeled carriage, and had a magnifying glass attachment.
label: Description
content: Willis noted that date on this instrument, but it bears little resemblance to the patent drawings. A brass arm with metal tracers at both ends moves perpendicularly to a brass frame. The arm is evenly divided in increments marked 99, 88, 77, 66, 55, 44, and 33. A metal bar at the front of the frame has a brass slide. Next are two brass wheels on spindles fastened to a brass plate in the center. At the back is a wooden triangular ruler with six scales on white celluloid. These scales divide the inch into 100, 50, 60, 30, 80, and 40 parts. The ruler is marked: J. L. ROBERTSON & SONS, N.Y. Presumably, the ruler came from one of the Improved Willis Planimeters made by Robertson between 1896 and the 1910s. The back of the frame is marked: E. J. WILLIS (/) RICHMOND, VA. (/) PAT. APL'D FOR.
label: Description
content: A metal rod has rectangular brass ends. A triangular metal plate has brass bolts holding prickers and a brass post that holds one end of the rod. A small brass clamp is loose in the crudely made wooden case, which appears to be made from a shipping crate. Handwriting on the inside of the lid reads: Edward J. Willis (/) Room 119 Mutual Bldng (/) P.O. Box 416 Richmond V<u>a</u> (/) Jany 17<sup><u>h</u></sup> 1922 (/) WILLIS TWO WHEEL PLANIMETER. There is no record of a patent that applies specifically to this apparent prototype.
label: Description
content: For information on Willis's earlier patents and planimeters, see 1994.0356.02, MA.324247, MA.323703, and MA.323704. At the same time that Willis worked on his later planimeters, he became interested in celestial navigation and published two textbooks on the subject. He invented a navigating machine and an altitude-azimuth instrument in the 1930s.
label: Description
content: According to the accession file, this instrument was received at the Smithsonian in 1982 or 1983.
label: Description
content: References: Edward J. Willis, "Planimeter" (U.S. Patent 1,404,180 issued January 17, 1922); Hyman A. Schwartz, "The Willis Planimeter," <i>Rittenhouse</i> 7, no. 2 (1993): 60–64; Willem F.J. Mörzer Bruyns, "The Willis Navigating Machine: A Forgotten Invention," <i>Rittenhouse</i> 14 (June 2000): 13–25.
label: Location
content: Currently not on view
place: label: place made
content: United States: Virginia, Richmond
topic: label: Subject
content: Mathematics
label: Subject
content: Invention
label: Subject
content: Engineering
setName: label: See more items in
content: Medicine and Science: Mathematics
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content: Planimeters
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content: Science & Mathematics
creditLine: label: Credit Line
content: Gift of John H. White, Jr.
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1983.0173.01
label: catalog number
content: 1983.0173.01
label: accession number
content: 1983.0173
objectType: label: Object Name
content: planimeter
physicalDescription: label: Physical Description
content: brass (overall material)
label: Physical Description
content: steel (overall material)
label: Physical Description
content: wood (overall material)
label: Physical Description
content: celluloid (overall material)
label: Measurements
content: case: 5.2 cm x 31 cm x 10 cm; 2 1/16 in x 12 7/32 in x 3 15/16 in