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Irregular or French Curve

Irregular or French Curve

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This flat wooden drawing instrument has curves on the outside and in an inner opening. It also has two small holes.
The previous owner of this object collected more than twelve hundred hand and machine tools, displaying them at his family's building company in Baltimore, Md. This device came in a tool chest along with several others.
The shape of the curve (though not the holes) is similar to an instrument shown in a Reeves & Sons catalog from 1904. It also resembles one shown in Wallis and in McAllister as early as 1881 (there with one small hole). Hence the very rough date assigned.
Compare 1977.1101.0095.
Maya Hambly, Drawing Instruments, London: RIBA Drawings Collection, 1982, p. 32.
Accession File.
Roland S. Wallis, Industrial Education Notes on Mechanical Drawing, Ames, Iowa: Engineering Extension Department Iowa State College, 1922, p. 15.
William Y. McAllister, Priced and Illustrated catalogue..., Philadelphia, 1881, pp. 43-44.
Currently not on view
Object Name
date made
Physical Description
wood (overall material)
overall:.2 cm x 21.3 cm x 7.4 cm; 3/32 in x 8 3/8 in x 2 29/32 in
ID Number
accession number
catalog number
Credit Line
The John R. Gerwig, Jr., Collection
Drawing Instruments
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Data Source
National Museum of American History
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