Safe-T Semicircular School Protractor

Social Media Share Tools

Object Details

Safe-T Products, Inc.

Description: 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.
Location: Currently not on view

Credit Line: Collected at the American Mathematical Society annual meeting, 8 January 1998

1998

Physical Description: plastic (overall material)
Measurements: overall: .1 cm x 15.8 cm x 8.5 cm; 1/32 in x 6 7/32 in x 3 11/32 in

See more items in: Medicine and Science: Mathematics; Science & Mathematics; Protractors

National Museum of American History

GUID (Link to Original Record): http://n2t.net/ark:/65665/ng49ca746a5-1caf-704b-e053-15f76fa0b4fa