Geometric Models, L. Brill No. 99. Ser. 3 No. 9, Two Hyperboloids of Two Sheets
date: label: date made
content: 1892
name: label: maker
content: L. Brill
notes: label: Description
content: In the nineteenth and early twentieth century, students studying technical subjects often learned about the representation of surfaces by equations in courses in solid analytic geometry. Schools in Europe, the United States, and Japan sometimes purchased models to illustrate such surfaces. These objects are part of series of models of quadric surfaces (surfaces of degree two) designed in 1878 by Rudolf Diesel, then a student at the technical high school in Munich. They were published by the firm of Ludwig Brill in Darmstadt. These examples were exhibited at the German Educational Exhibit at the Columbian Exposition held in Chicago in 1893, where they were purchased by Wesleyan University.
label: Description
content: The plaster models show a hyperboloid of two sheets. The surface can be represented by the equation x<sup>2</sup>/a<sup>2</sup> + y<sup>2</sup>/ b<sup>2</sup> + z<sup>2</sup>/c<sup>2</sup> = - 1. Sections parallel to the plane z=0 are ellipses. Sections by the planes x=0 and y=0, and planes parallel to these, are hyperbolas. Two metal rods hold together the two sheets of each model.
label: Description
content: Grids of perpendicular lines of curvature are shown. A paper tag on one models reads: 99. Paper tags on both of them read: Zweischaliges Hyperboloid. (/) Verl. v. L. Brill. 3. Ser. Nr. 9.
label: Description
content: Compare 1990.0571.07.
label: Description
content: References:
label: Description
content: Ludwig Brill, <I>Catalog mathematischer Modelle. . .</I>, Darmstadt: L. Brill, 1892, p. 7, 77.
label: Description
content: Henry Burchard Fine and Henry Dallas Thompson, <I>Coordinate Geometry</I>, New York: Macmillan Company, 1931, pp. 240-241.
label: Description
content: Gerard Fischer, <I>Mathematical Models</I>, Braunschweig / Wiesbaden: Friedr. Vieweg & Sohn, 1986, vol. I, p. 62, vol. II, pp.25-28.
label: Location
content: Currently not on view
place: label: place made
content: Germany: Hesse, Darmstadt
topic: label: Subject
content: Mathematics
setName: label: See more items in
content: Medicine and Science: Mathematics
label: See more items in
content: Science & Mathematics
creditLine: label: Credit Line
content: Gift of Wesleyan University
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1985.0112.072
label: catalog number
content: 1985.0112.072
label: accession number
content: 1985.0112
objectType: label: Object Name
content: Geometric Model
label: Object Name
content: geometric model
physicalDescription: label: Physical Description
content: metal (overall material)
label: Physical Description
content: plaster (overall material)
label: Measurements
content: each: 23.5 cm x 21 cm x 13 cm; 9 1/4 in x 8 9/32 in x 5 1/8 in