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Model of a Twisted Cubic by Richard P. Baker, Baker #72 (a Ruled Surface)

Model of a Twisted Cubic by Richard P. Baker, Baker #72 (a Ruled Surface)

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This string model was constructed by Richard P. Baker, possibly before 1905 when he joined the mathematics faculty at the University of Iowa. Baker believed that models were essential for the teaching of many parts of mathematics and physics, and over one hundred of his models are in the museum collections. Baker mentioned the model in a 1905 listing of one hundred models he had constructed as well as in a 1931 catalog.
A typed paper label on the top of the wooden base of this model reads: No. 72 (/) TWISTED CUBIC (/) (by cone and cylinder).
Like several other models Baker made, this shows ruled surfaces, also called scrolls. Such a surface is swept out by a moving line. The two ruled surfaces shown here are a cylinder, indicated with red threads, and a double cone, indicated in yellow. The points where the surfaces intersect are indicated by a wire. The curve of intersection is of degree three and is known as a twisted cubic.
The model sold for $4.00.
R. P. Baker, A List of Mathematical Models, [1905], p. 13.
R. P. Baker, Mathematical Models, Iowa City, Iowa, 1931, p. 72.
R. P. Baker Papers, University of Iowa, Iowa City, Iowa.
George Salmon, A Treatise on the Analytic Geometry of Three Dimensions, Dublin: Hodges, Foster, and Company, 1874, esp. pp. 303-313.
Currently not on view
Object Name
geometric model
date made
ca 1900-1935
Baker, Richard P.
Physical Description
thread (overall material)
wood (overall material)
metal (overall material)
red (overall color)
black (overall color)
yellow (overall color)
screwed and threaded (overall production method/technique)
average spatial: 13.9 cm x 25.9 cm x 20.2 cm; 5 15/32 in x 10 3/16 in x 7 15/16 in
ID Number
accession number
catalog number
Credit Line
Gift of Frances E. Baker
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Data Source
National Museum of American History
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