Open Triangle

This 12" 45°-45°-90° triangle with an open interior is made of three different woods, with two sections of lighter wood (0.5 cm wide) around two sections of darker wood (0.8 cm wide) around one section of reddish wood (1 cm wide). Three horizontal splines made from the lighter wood reinforce each corner. The back of the object has a sticker marked: 364.
Neither Keuffel & Esser nor the Eugene Dietzgen Company advertised triangles like this one. James W. Queen of Philadelphia offered only two-toned triangles, of walnut or mahogany with a maple or ebony inlay. Additionally, the firm did not sell inlaid triangles in a 12-inch size. The previous owner of this instrument collected more than 1,200 hand tools and machine tools and displayed them at his family's building company in Baltimore, Md. This object was item number 364 in his collection.
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
pearwood (overall material)
mahogany (overall material)
walnut (overall material)
overall: 30.5 cm x 30.5 cm x .3 cm; 12 in x 12 in x 1/8 in
ID Number
catalog number
accession number
Credit Line
The John R. Gerwig, Jr., Collection
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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