Dietzgen Limb Protractor
date: label: date made
content: ca 1900
name: label: maker
content: Eugene Dietzgen Company
notes: label: Description
content: This German silver protractor is in the shape of a quarter-circle. It is divided by half-degrees and marked by tens from 0° to 90°. Flat bars extend on both sides of the protractor. A movable arm extends from the vertex of the quadrant. A tab is cut out from this limb to permit reading the angle markings. The arm is secured by a brass thumbscrew that is near the origin point for the angle markings. The protractor is noticeably rusted and tarnished.
label: Description
content: There is a signature on the bottom edge: E. D. – Co. (/) NEW YORK & CHICAGO. Around 1880, Eugene Dietzgen emigrated from Germany and became a sales distributor for Keuffel & Esser in New York. In 1885, he began to sell mathematical instruments on his own in Chicago. In 1893, his firm started manufacturing instruments under the name Eugene Dietzgen Company. However, this protractor was not advertised in Dietzgen catalogs that were published between 1902 and 1947.
label: Description
content: Leslie Leland Locke (1875–1943) originally owned this protractor. A student at Grove City College, he earned a bachelor's degree in 1896 and a master's degree in 1900. He taught mathematics at Michigan State College, Adelphi College, and Brooklyn College and its Technical High School. He was interested in Peruvian <i>quipu</i>, mysterious and ancient systems of knotted strings used to store and communicate information and data. He donated his collection of early calculating machines to the Smithsonian and his early American textbooks to the University of Michigan.
label: Description
content: Reference: Louis C. Karpinski, "Leslie Leland Locke," <I>Science</I> n.s., 98, no. 2543 (24 September 1943): 274–275.
label: Location
content: Currently not on view
topic: label: Subject
content: Mathematics
label: Subject
content: Protractor
setName: label: See more items in
content: Medicine and Science: Mathematics
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content: Science & Mathematics
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content: Protractors
creditLine: label: Credit Line
content: Gift of Grove City College
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 2011.0129.01
label: accession number
content: 2011.0129
label: catalog number
content: 2011.0129.01
objectType: label: Object Name
content: protractor
physicalDescription: label: Physical Description
content: german silver (overall material)
label: Measurements
content: overall: 1.5 cm x 17.5 cm x 17.7 cm; 19/32 in x 6 7/8 in x 6 31/32 in