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.

Date Made: 1937

Teacher Of Maker: Wheeler, Albert HarryMaker: Chaffe, Robert

Location: Currently not on view

Place Made: United States: Massachusetts, Worcester

Subject: Mathematics


See more items in: Medicine and Science: Mathematics, Science & Mathematics, Mathematical Association of America Objects


Exhibition Location:

Credit Line: Gift of Helen M. Wheeler

Data Source: National Museum of American History

Id Number: MA.304723.180Accession Number: 304723Catalog Number: 304723.180

Object Name: geometric model

Physical Description: wood, balsa (overall material)tan (overall color)cut and glued (overall production method/technique)Measurements: 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


Record Id: nmah_1066641

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