Geometric Model by Robert Chaffe, a Student of A. Harry Wheeler, Hyperbolic Paraboloid

Suppose two opposite sides of a rectangle are joined by straight lines parallel to the other two sides. Lifting two opposite corners of the rectangle—and keeping the lines taut—one obtains a saddle-shaped figure known as a hyperbolic paraboloid.
This model of a hyperbolic paraboloid was made from balsa wood by Robert Chaffe, a high school student of A. Harry Wheeler in the class of 1937. It is likely that this person is Robert C. Chaffe (1918–1991) who was born in Connecticut, attended high school in Worcester, Massachusetts, graduated from the Worcester Polytechnic Institute in 1942, and seems to have spent his career as a salesman and sales engineer in Worcester and nearby Auburn.
Gerd Fischer, Mathematical Models, vol. 2, Braunschweig/Wiesbaden: Friedr. Vieweg & Sohn, 1986, pp. 3–4.
U.S. Census records.
Massachusetts city directories.
Currently not on view
Object Name
geometric model
date made
teacher of maker
Wheeler, Albert Harry
Chaffe, Robert
Physical Description
wood, balsa (overall material)
tan (overall color)
cut and glued (overall production method/technique)
average spatial: 12.5 cm x 21.6 cm x 15.5 cm; 4 29/32 in x 8 1/2 in x 6 3/32 in
place made
United States: Massachusetts, Worcester
ID Number
accession number
catalog number
Science & Mathematics
Mathematical Association of America Objects
See more items in
Medicine and Science: Mathematics
Mathematical Association of America Objects
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Gift of Helen M. Wheeler
Additional Media

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