Ruled Surface with Chrome Frame, Two Perpendicular Right Circular Cylinders


This ruled surface has a chrome frame. The top and bottom of the frame have equal and opposite circular rings, with a ring of holes around both edges. Vertical yellow threads join these holes to form a cylinder. Two opposite sides of the frame also have equal and opposite circular rings, with holes around the edges of the rings. These circles are joined by horizontal red threads to form another right circular cylinder, perpendicular to the first one.

This is one of eight models of rules surfaces having a chrome frame given to the Smithsonian by Brown University (see MA.304722.35 through MA.304722.42). All these models are unsigned. Models of this general appearance were shown by Saul Pollock of Indiana State Teacher’s College in Terre Haute, Indiana, at the Century of Progress world’s fair, held in Chicago in 1934. A. Harry Wheeler, a mathematics teacher and maker of geometric models, visited the fair and noted Pollock’s models. Wheeler also communicated with mathematicians at Brown, and exhibited some of his models there. The models might be by Pollock, they might be copies by Wheeler.


Century of Progress, Official Handbook of Exhibits in the Division of the Basic Sciences Hall of Science, Chicago, 1934, p. 39-40, 43.

P.A. Kidwell, “American Mathematics Viewed Objectively: The Case of Geometric Models,” Vita Mathematica, ed. Ronald Calinger, Washington, DC: Mathematical Association of America, 1996, pp. 197-207.

Date Made: ca 1934

Location: Currently not on view

Subject: Mathematics


See more items in: Medicine and Science: Mathematics, Science & Mathematics


Exhibition Location:

Credit Line: Gift of Brown University Department of Mathematics

Data Source: National Museum of American History

Id Number: MA.304722.39Catalog Number: 304722.39Accession Number: 304722

Object Name: geometric model

Physical Description: chrome (overall material)thread (overall material)Measurements: overall: 30.8 cm x 21 cm x 21 cm; 12 1/8 in x 8 9/32 in x 8 9/32 in


Record Id: nmah_1213874

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