Geometric Model, L. Brill No. 76. Ser. 9 No. 9, Fourth Order Surface


The design of this plaster model follows one built Edward Kummer (1810-1893), a mathematics professor in Berlin. Examples were first published by Brill in 1883.

The model represents a cross-cap, the self-intersection of a one-sided surface. It is a Dupin cyclide with a double curve, the self-intersection of the surface with two different tangential planes. A torn paper tag reads: [. . .}6. A second tag reads: Fl. 4. Ord. mit 1 Doppelgeraden. (/) Verl. v. L. Brill. 9. Ser. Nr. 9.

This example was exhibited at the Columbian Exposition, a world’s fair held in Chicago in 1893.


L. Brill, Catalog mathematischer Modelle. . ., Darmstadt: L. Brill, 1892, p. 19.

Fischer, Gerd, ed., Mathematical Models, vol. 1, Braunschweig / Wiesbaden: Vieweg, 1986, p. 108.

Fischer, Gerd, ed., Mathematical Models, vol. 2, Braunschweig / Wiesbaden: Vieweg, 1986, pp. 63-64.

Groeningen University website, accessed September 2, 2019.

Date Made: 1892

Maker: L. Brill

Location: Currently not on view

Place Made: Germany: Hesse, Darmstadt

Subject: Mathematics

See more items in: Medicine and Science: Mathematics, Science & Mathematics


Exhibition Location:

Credit Line: Gift of Wesleyan University

Data Source: National Museum of American History

Id Number: 1985.0112.056Catalog Number: 1985.0112.056Accession Number: 1985.0112

Object Name: geometric modelgeometric model

Physical Description: plaster (overall material)Measurements: overall: 3 cm x 9.5 cm x 9.5 cm; 1 3/16 in x 3 3/4 in x 3 3/4 in


Record Id: nmah_693932

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