Safe-T Semicircular School Protractor
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- Safe-T Products, Inc.
- This clear plastic semicircular protractor arrived at the Smithsonian in a clear plastic wrapper, which is stored with it. Designed for use by schoolchildren, it contains four sets of divisions, three to single degrees and the innermost one to ten degrees.
- The outer two divisions are marked by tens for reading left-opening angles, from 0° to 180°. The inner two divisions are marked by tens for reading right-opening angles, from 170° to 0°. A semicircular slot separates the two scales.
- The interior of the protractor is open. A scale along the bottom edge of the opening is divided to millimeters and marked by centimeter from 0 to 10. The outer bottom edge of the protractor is divided to sixteenths of an inch and is marked by inches from 1 to 6. The corners are slightly rounded.
- The object bears several marks along its diameter edge: PAT. [/] PENDING; SAFE-T TM [/] PRORUCTS [sic] Inc.; Angles Opening Left (>) [/] Use Upper Scale; VIEW-THRU TM [/] SAFE-T PLASTIC TM [/] #45780; Angles Opening Right (<) [/] Use Lower Scale; La Grange, IL [/] 60525-0692.
- Reference: SAFE-T Products, Inc., Innovative Safe Drawing and Measuring Instruments, about 1998. According to this catalog, these protractors sold individually for 75 cents. In 2006, the company became a subsidiary of A. Daigger & Company and its name changed to Classroom Products Warehouse.
- Currently not on view
- Credit Line
- Collected at the American Mathematical Society annual meeting, 8 January 1998
- ID Number
- catalog number
- accession number
- Object Name
- Physical Description
- plastic (overall material)
- overall: .1 cm x 15.8 cm x 8.5 cm; 1/32 in x 6 7/32 in x 3 11/32 in
- place made
- United States: Illinois, La Grange
- See more items in
- Medicine and Science: Mathematics
- Science & Mathematics
- National Museum of American History
- Education, High School
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