Felsenthal Artillery Protractor


This clear plastic semicircular protractor is divided by tens and marked by hundreds from 100 to 3,100 mils and from 3,300 to 6,300 mils. Mils are units used in artillery and other military applications; 1,000 mils is equivalent to 56.25°. A pinhole is at the origin point. The bottom edge of the protractor is divided by hundreds and marked by five hundreds from 0 to 8,000 yards. A small vernier appears to the left of the scale, and the scale is labeled: 1/20,000.

The interior of the protractor has a semicircular opening with a groove parallel to the origin point. Below the opening is a maker's mark: 16 INCH (/) G. FELSENTHAL & SONS, INC. (/) -CHICAGO-. The letters U.S. are printed above the origin point. Donor Ben Rau, who worked for Felsenthal, dated the object to 1942. The form of the maker's name indicates it was probably manufactured for the U.S. Army in the 1950s.

This protractor is very similar to 1977.1141.11, although the scale for plotting the distance of fired artillery is in yards rather than in meters.

See also 1977.1141.01, 1977.1141.02, 1977.1141.03, 1977.1141.05, 1977.1141.08, 1977.1141.09, 1977.1141.10, 1977.1141.12, 1977.1141.19, 1977.1141.20, 1977.1141.21, 1977.1141.22, 1977.1141.23, 1977.1141.24, 1977.1141.30, and 1977.1141.39.

Date Attributed By Donor: 1942Date Made: 1950s

Maker: G. Felsenthal & Sons, Inc.

Location: Currently not on view

Place Made: United States: Illinois, Chicago

Subject: MathematicsProtractorArtillery


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


Exhibition Location:

Credit Line: Gift of Ben Wharton Rau and Margery Felsenthal Rau

Data Source: National Museum of American History

Id Number: 1977.1141.18Accession Number: 1977.1141Catalog Number: 336402

Object Name: protractor

Physical Description: plastic (overall material)Measurements: overall: .2 cm x 40.3 cm x 21.7 cm; 3/32 in x 15 7/8 in x 8 17/32 in

Guid: http://n2t.net/ark:/65665/ng49ca746a7-248d-704b-e053-15f76fa0b4fa

Record Id: nmah_904370

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