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Geometric Model, L. Brill No. 136. Ser. 8 No. 20, Surface of Rotation of Constant Negative Curvature (Kuen's Surface)

Geometric Model, L. Brill No. 136. Ser. 8 No. 20, Surface of Rotation of Constant Negative Curvature (Kuen's Surface)

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This plaster model is was originally constructed under the supervision of Alexander Brill by J. Mack, a student at the technical high school in Munich, along ideas of L. Bianchi, A. Enneper and Th. Kuen. It was first published in 1882. This example of the model is presently in two pieces.
A paper tag on the model reads: 136. Another paper tag reads: Fläche const. negat. Krűmung. (/) verl. V. L. Brill 8 Ser. Nr. XX.
This example of the model was exhibited at the German Educational Exhibit at the Columbian Exposition, a World’s Fair held in Chicago in 1893. It there was purchased by Wesleyan University in Connecticut, and subsequently was donated to the Smithsonian.
The surface has attracted the attention of artists as well as mathematicians.
L. Brill, Catalog mathematischer Modelle..., Darmstadt: L. Brill,1892, p. 17, 82.
Accession file.
G. Fischer, Mathematical Models, I, p. 82 (photograph 86), vol. 2, p. 38.
Currently not on view
Object Name
geometric model
geometric model
date made
L. Brill
place made
Germany: Hesse, Darmstadt
Physical Description
plaster (overall material)
overall: 25.5 cm x 16 cm x 18 cm; 10 1/32 in x 6 5/16 in x 7 3/32 in
ID Number
catalog number
accession number
Credit Line
Gift of Wesleyan University
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Medicine and Science: Mathematics
Science & Mathematics
Data Source
National Museum of American History
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