Open Triangle

This unmarked 8" 30°-60°-90° triangle with an open interior is made of two different woods, with a section of darker wood laid between two sections of lighter wood. The dating of other objects from this donor suggests the triangle was made around 1900. Compare to MA.335330. Neither Keuffel & Esser nor the Eugene Dietzgen Company advertised triangles like this one. James W. Queen of Philadelphia did offer walnut or mahogany triangles with a maple inlay, but the firm did not sell the instrument in the 8-inch size.
Reference: James W. Queen & Co., Priced and Illustrated Catalogue of Mathematical Instruments (Philadelphia, 1883), 51.
Currently not on view
date made
ca 1900
Physical Description
wood (overall material)
overall: 11.7 cm x 20 cm x .5 cm; 4 19/32 in x 7 7/8 in x 3/16 in
ID Number
catalog number
accession number
Credit Line
Gift of Eunice L. Hoffman
Drawing Instruments
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Squares and Triangles
Data Source
National Museum of American History


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