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Dissected Rhomboid, Ross Surface Form #5 (incomplete)

Dissected Rhomboid, Ross Surface Form #5 (incomplete)

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This is the fifth in a series of models of plane figures (surface forms) designed by William Wallace Ross, a school superintendent and mathematics teacher in Fremont, Ohio. The unpainted wooden model is divided into two pieces, with the smaller piece missing.
With the smaller piece, the model could be arranged either as a parallelogram or a rectangle. A paper label attached to the model reads: Dissected Rhomboid 4x6.
Ross argued that the parallelogram (or, in his terminology, rhomboid), like the rectangle, was the product of its length and its altitude.
Compare models 1985.0112.190 through 1985.0112.202.
For further information about Ross models, including references, see 1985.0112.191.
Currently not on view
Object Name
geometric model
date made
ca 1895
Ross, W. W.
place made
United States: Ohio, Fremont
Physical Description
wood (overall material)
overall: 1 cm x 15 cm x 10 cm; 13/32 in x 5 29/32 in x 3 15/16 in
ID Number
accession number
catalog number
Credit Line
Gift of Wesleyan University
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Arithmetic Teaching
Data Source
National Museum of American History
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