J. L. Hammett Co. Open Triangle

This 17-1/4" 45°-45°-90° maple triangle is formed from three pieces of wood and has an open interior. The hypotenuse is marked: J. L. HAMMETT CO. (/) CAMBRIDGE. MASS. John Hammett began selling erasers and slating paint for chalkboards in Rhode Island in 1863, moving to Boston in 1865. In 1890 new owners expanded the firm into all forms of paper school supplies. J. L. Hammett operated over 50 retail stores from 1974 to 2005. The Department of Mathematics at Brown University gave this object to the Museum in 1973.
References: Bill Lane, "School Supplier J. L. Hammett to Close Stores," Boston Business Journal, January 4, 2005, http://www.bizjournals.com/boston/stories/2005/01/03/daily12.html; "J. L. Hammett Company," The Play and Playground Encyclopedia, http://www.pgpedia.com/j/jl-hammett-company.
Currently not on view
Object Name
date made
20th century
J. L. Hammett Co.
Physical Description
maple (overall material)
overall: 62 cm x 31.5 cm x .7 cm; 24 13/32 in x 12 13/32 in x 9/32 in
place made
United States: Massachusetts, Cambridge
ID Number
catalog number
accession number
Squares and Triangles
Science & Mathematics
Drawing Instruments
See more items in
Medicine and Science: Mathematics
Squares and Triangles
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Gift of Brown University Department of Mathematics
Additional Media

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