Integraph by G. Coradi
date: label: date made
content: ca 1910
name: label: maker
content: Coradi, Gottlieb
notes: label: Description
content: This instrument draws the integral of a function that is plotted when the curve representing the function is traced with the tracer. It rests on two German silver rollers attached to a common axle. A framework above the axle carries the tracer arm, the integrating mechanism, and the plotter. A pen point, a pencil point, a calibration bar, a brush, what may be a tracer point and a head for the pencil point are stored in the case.
label: Description
content: An inscription on the support for one wheel reads: G. Coradi Zurich. An inscription on the support for the other wheel reads: John R. Freeman (/) No. 121. A paper shed glued to the inside of the lid of the wooden case gives the value in centimeters of the ordinates for curves plotted using different bases.
label: Description
content: The integraphs sold by Coradi before about 1903 had a much larger framework surrounding the axle. A similar instrument in the collections of the Science Museum has serial number 173 and dates from 1911. Compare MA.336877.
label: Description
content: This instrument may well have been owned by the hydraulic and civil engineer and insurance executive John Ripley Freeman (1855-1932), an 1876 graduate of MIT. Freeman was president of Manufacturer's Mutual Fire Insurance Company of Providence, Rhode Island from the 1890s and also consulted on water power and municipal water supply projects.
label: Description
content: References:
label: Description
content: <I>Dictionary of American Biography</I>, Supplement 1 (1944).
label: Description
content: G. Coradi, <I>Catalogue of Mathematical Precision Instruments</I>, Zurich: Mathematical-Mechanical Institute of G. Coradi</I>, 1915, pp. 27-30. The integraph shown on page 28 is not precisely like this one.
label: Location
content: Currently not on view
place: label: place made
content: Switzerland: Zürich, Zurich
topic: label: Subject
content: Mathematics
setName: label: See more items in
content: Medicine and Science: Mathematics
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content: Mechanical Integrators and Analyzers
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content: Science & Mathematics
creditLine: label: Credit Line
content: Gift of Brown University Department of Mathematics
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: MA.304722.13
label: catalog number
content: 304722.13
label: accession number
content: 304722
objectType: label: Object Name
content: integraph
physicalDescription: label: Physical Description
content: German silver (parts material)
label: Physical Description
content: brass (parts material)
label: Physical Description
content: wood (case material)
label: Physical Description
content: cloth (lining material)
label: Measurements
content: overall: 18.3 cm x 48 cm x 31 cm; 7 7/32 in x 18 29/32 in x 12 7/32 in