Hart Combination Protractor, Rule, and Square

Hart Combination Protractor, Rule, and Square

Usage conditions apply
This paper semicircular protractor is divided by degrees and marked by tens from 10 to 170 degrees in both directions. The letter A is printed in the bottom left corner of the protractor, and B is printed in the bottom right corner of the protractor. Centered under the origin point of the protractor is printed the inventor's mark: Combination Protractor, Rule, and Square (/) W. W. Hart, University of Wisconsin.
A ruler along the top edge is divided to 1/8-inch and marked by ones from 0 to 5. A ruler along the bottom edge is divided to millimeterS and marked by ones from 0 to 12. The typeface of the inventor's mark is similar to that shown in Hart's textbooks published in the 1920s, such as Walter Wilson Hart, Junior High School Mathematics, vol. 1 (Boston: D. C. Heath & Co., 1921), vii, 131. See also MA.304722.06.
Currently not on view
Object Name
date made
ca 1925
Hart, Walter Wilson
place made
United States: Wisconsin, Madison
Physical Description
paper (overall material)
overall:.1 cm x 13.5 cm x 8.2 cm; 1/32 in x 5 5/16 in x 3 7/32 in
ID Number
accession number
catalog number
Credit Line
Gift of Brown University Department of Mathematics
Education, High School
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Data Source
National Museum of American History
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I have one of these dated Sept 9, 1925. It was my dad's.

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