Keuffel and Esser Square Root Planimeter, Model 62 0105, Made by Ott
date: label: date made
content: ca 1955
name: label: maker
content: Keuffel & Esser Co.
notes: label: Description
content: Most planimeters measure the area bounded by a closed curve. In the mid-1950s, Keuffel & Esser began selling planimeters for other purposes. This one computes the mean square root of a function graphed on a circular chart. The specific design depended on the chart. This example was made for Keuffel & Esser by the German firm of Ott for use with a Brown 12051 chart. Brown Instrument Company of Philadelphia, from 1934 a subsidiary of Honeywell, manufactured a large number of industrial control devices, including flow meters. A 1942 catalog lists the 12051 recorder chart as designed for electric flow meters. A chart of the same range (unclear whether it had the same number) was also available for Brown mechanical flow meters.
label: Description
content: The planimeter fits in a leather-covered case lined with green velvet. The case also contains a pin and pin extractor.
label: Description
content: This instrument was donated to the Smithsonian in 2016.
label: Description
content: References:
label: Description
content: Accession File.
label: Description
content: Brown Instrument Company, <I>Mechanical Meters Flow and Liquid Level</I>, Philadelphia, 1942, pp. 28-29.
label: Description
content: Keuffel & Esser Company, <I>Catalogue</I>, 1955, p. 289.
label: Description
content: Keuffel & Esser Company, <I>Catalogue</I>, 1962, pp. 6-37.
label: Description
content: Leise, Tanya. "As the Planimeter's Wheel Turns: Planimeter Proofs for Calculus Class." <I>The College Mathematics Journal</I> 38, no. 1, 2007, pp. 24-31.
label: Location
content: Currently not on view
topic: label: Subject
content: Mathematics
setName: label: See more items in
content: Medicine and Science: Mathematics
label: See more items in
content: Planimeters
label: See more items in
content: Science & Mathematics
creditLine: label: Credit Line
content: Gift of Maximilian Berktold
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 2016.0064.05
label: catalog number
content: 2016.0064.05
label: accession number
content: 2016.0064
objectType: label: Object Name
content: planimeter
physicalDescription: label: Physical Description
content: stainless steel (instrument, tack, fasteners material)
label: Physical Description
content: plastic (measuring wheels material)
label: Physical Description
content: paper (labels material)
label: Physical Description
content: cover of case (leather material)
label: Physical Description
content: lining of case (velvet material)
label: Measurements
content: overall: 5 cm x 19.9 cm x 13.5 cm; 1 31/32 in x 7 27/32 in x 5 5/16 in