Geometric Model, L. Brill No. 11. Ser. 4 No. 1, Hyperboloid of One Sheet and Double Cone

This string model with a metal frame shows two ruled surfaces, that is to say surfaces swept out by moving straight lines. On the outside, shown in gold threads, is a doubly ruled hyperboloid of one sheet with an elliptic base and top. On the inside is a doubly ruled elliptic double cone, erected on the same base and top and shown in red.
The model 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.
Ludwig Brill, Catalog mathematischer Modelle. . ., Darmstadt: L. Brill, 1892, p. 9, 58.
Henry Burchard Fine and Henry Dallas Thompson, Coordinate Geometry, New York: Macmillan Company, 1931, pp. 251-253. An example of this model is shown in Figure 6.
Currently not on view
date made
L. Brill
place made
Deutschland: Hessen, Darmstadt
Physical Description
metal (frame material)
thread (surface material)
overall: 25.5 cm x 23 cm x 14.5 cm; 10 1/16 in x 9 1/16 in x 5 11/16 in
ID Number
catalog number
accession number
Credit Line
Gift of Wesleyan University
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Data Source
National Museum of American History


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