Geometric Model, L. Brill No. 21. Ser. 3 No. 11, Elliptic Paraboloid
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. This object is 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. It was published by the firm of Ludwig Brill in Darmstadt. This example was exhibited at the German Educational Exhibit at the Columbian Exposition held in Chicago in 1893, where it was purchased by Wesleyan University.
label: Description
content: The plaster model shows elliptic paraboloid. The surface is represented by the equation: x<sup>2</sup>/a<sup>2</sup> + y<sup>2</sup>/ b<sup>2</sup> = -2z. The apex of the surface is at the origin (so that all the values of z are negative). Sections by the planes x = 0 and y = 0, as well as by planes parallel to them, are parabolas. Sections parallel to and below the plane z = 0 are ellipses that increase in size going downward.
label: Description
content: This model has twelve ellipses on it, parallel to the base. A tag at the front reads: Elliptisches Paraboloid. (/) Verl. v. L. Brill. 3 Ser. Nr. 11.
label: Description
content: Compare 1985.0112.015 , 1985.0112.016, and 1985.0112.017.
label: Description
content: References:
label: Description
content: Ludwig Brill, <I>Catalog mathematischer Modelle. . .</I>, Darmstadt: L. Brill, 1892, p. 7, 59.
label: Description
content: Henry Burchard Fine and Henry Dallas Thompson, <I>Coordinate Geometry</I>, New York: Macmillan Company, 1931, p. 242. An example of this Brill model is shown as Figure 4.
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: 1985.0112.016
label: catalog number
content: 1985.0112.016
label: accession number
content: 1985.0112
objectType: label: Object Name
content: geometric model
physicalDescription: label: Physical Description
content: paper (overall material)
label: Physical Description
content: plaster (overall material)
label: Measurements
content: overall: 20 cm x 19 cm x 12 cm; 7 7/8 in x 7 15/32 in x 4 23/32 in