Gilson Midget Circular Slide Rule
date: label: date made
content: ca 1940
name: label: maker
content: Gilson Slide Rule Company
notes: label: Description
content: This two-sided circular slide rule is a white plastic disc with two transparent, pivoting green plastic arms on one side and a third arm on the back. On the front, from the edge to the center, there is a C scale, CI scale, a scale of logarithms, a scale of squares, a "binary" scale, a log-log scale, a scale for the decimal equivalent of fractions, a scale of drill sizes, and a scale of thread sizes. The rule is marked: MADE IN U.S.A. (/) Copyrighted 1936 (/) Patented.
label: Description
content: Three concentric circles forming a scale of degrees, sines, and tangents are on the back. Inside this scale is a scale of decimal equivalents for fractions. The back of the instrument is marked: COPYRIGHTED (/) 1931.
label: Description
content: The rule has a green synthetic leather case. On the inside of the flap, it is marked in ink: Donald Mela, and stamped in red: Gordon's (/) DRAFTING MATERIALS (/) 162 W. Madison St. Chicago. The instrument was received with a small paper manual, 1998.0119.03. See also 1989.0032.01.
label: Description
content: Claire A. Gilson founded the Gilson Slide Rule Company in Niles, Mich., in 1915. The firm moved to Stuart, Fla., in 1927 and remained in business until about 1975. This example of the firm's Midget model was probably manufactured around 1940.
label: Description
content: References: Henry Aldinger and Ed Chamberlain, "Gilson Slide Rules," <i>Journal of the Oughtred Society</i> 9, no. 1 (2000): 48–60 and 9, no. 2 (2000): 47–58; Bobby Feazel, "[Letters of] Richard A. Gilson," <i>Journal of the Oughtred Society</i> 2, no. 2 (1993): 8–12; Ross Grable, "Analysis of a Gilson Circular Rule," <i>Journal of the Oughtred Society</i> 7, no. 1 (1998): 53–55; International Slide Rule Museum, "Time Line for Gilson Slide Rule Company," http://sliderulemuseum.com/SR_Dates.htm#Gilson.
label: Location
content: Currently not on view
place: label: place made
content: United States: Florida, Stuart
topic: label: Subject
content: Rule, Calculating
label: Subject
content: Mathematics
label: Subject
content: Manufacturing
setName: label: See more items in
content: Medicine and Science: Mathematics
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content: Science & Mathematics
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content: Trigonometry
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content: Slide Rules
creditLine: label: Credit Line
content: Gift of Donald F. Mela
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1998.0119.01
label: catalog number
content: 1998.0119.01
label: accession number
content: 1998.0119
objectType: label: Object Name
content: calculating rule
label: Object Name
content: slide rule
physicalDescription: label: Physical Description
content: metal (part material)
label: Physical Description
content: plastic (overall material)
label: Physical Description
content: cloth (case material)
label: Measurements
content: overall: 11.6 cm x 12.4 cm x .5 cm; 4 9/16 in x 4 7/8 in x 3/16 in