Geometric Models, L. Brill No. 98. Ser. 3 No. 18, Elliptic Cones
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 particular 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: Each of these two plaster model shows an elliptic cone. 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> = 0. Here x and y are axes in the horizontal plane and z is the vertical axis. Assuming that z=0 at the apex of the cone, a plane cutting the surface parallel to the plane z = 0 produces an ellipse. Paper tags on both of the models read: Kegel. [/] Verl. v. L. Brill. 3. Ser. Nr. 18. A tag on one of them reads: 98. Both models are marked with a system of perpendicular lines of curvature.
label: Description
content: Compare 1990.0571.16.
label: Description
content: References:
label: Description
content: Ludwig Brill, <I>Catalog mathematischer Modelle. . .</I>, Darmstadt: L. Brill, 1892, p. 7, 76.
label: Description
content: Gerard Fischer, <I>Mathematical Models</I>, Braunschweig / Wiesbaden: Friedr. Vieweg & Sohn, 1986, vol. I, p. 63, 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: 1985.0112.071
label: catalog number
content: 1985.0112.071
label: accession number
content: 1985.0112
objectType: label: Object Name
content: Geometric Model
label: Object Name
content: geometric model
physicalDescription: label: Physical Description
content: plaster (overall material)
label: Measurements
content: each: 13.3 cm x 23 cm x 15 cm; 5 1/4 in x 9 1/16 in x 5 29/32 in