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Safe-T Semicircular School Protractor

American History Museum

Safe-T Products 45780 protractor
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Object Details

maker

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

date made

1998

ID Number

1998.0033.02

catalog number

1998.0033.02

accession number

1998.0033

Object Name

protractor

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

place made

United States: Illinois, La Grange

See more items in

Medicine and Science: Mathematics
Science & Mathematics
Protractors

Data Source

National Museum of American History

Subject

Mathematics
Education, High School

Metadata Usage

CC0

Link to Original Record

https://n2t.net/ark:/65665/ng49ca746a5-1caf-704b-e053-15f76fa0b4fa

Record ID

nmah_694146

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