Model of a Keil Trapezoid by Richard P. Baker, Baker #437

Model of a Keil Trapezoid by Richard P. Baker, Baker #437

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This is a model of trapezoidal wedge, a surface with two triangular and three trapezoidal faces.Here two triangular faces and two trapezoidal faces of a wedge are shown in sheet metal. Two interior intersecting triangles that bisect the wedge and join opposite sides of the triangles are also shown in sheet metal - the trapezoidal face that would cover them is not shown. Wires rising from two edges of one of these bisecting triangles aand from the line of intersection of the bisectors form two sides and the diagonal of a parallelogram.
Baker based this model on a diagram from a volume on dynamics by the German Eduard Study.
Baker, R. P., Mathematical Models, Iowa City, Iowa, 1931, p. 16.
Study, E., Geometrie der Dynamen: Die Zusammensetzung von kräften und verwandte Gegenstände der Geometrie, Leipzig: B.G. Teubner, 1901, esp. Figure 5 , p. 33.
Currently not on view
Object Name
geometric model
date made
ca 1906-1935
Baker, Richard P.
Physical Description
metal (overall material)
beige (overall color)
soldered. (overall production method/technique)
average spatial: 5.3 cm x 31 cm x 10.7 cm; 2 3/32 in x 12 7/32 in x 4 7/32 in
ID Number
catalog number
accession 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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