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Cubes, Conic Sections, and Crockett Johnson

Author(s): 
Stephanie Cawthorne (Trevecca Nazarene University) and Judy Green (Marymount University)

Or:  “What do the straightedge lines and compass arcs do when two parabolas and a hyperbola double a cube, just stand watching?”


In the early 1970s Crockett Johnson, author of the children’s book Harold and the Purple Crayon, sent a geometric diagram to a friend noting that the diagram “answers the question in so many minds ‘What do the straightedge lines and compass arcs do when two parabolas and a hyperbola double a cube, just stand watching?’” [Crockett Johnson to Mickey Rosenau, n.d., Rosenau Collection, Smithsonian Institution].  The diagram and the answer to this question are addressed at the end of this paper.

Stephanie Cawthorne (Trevecca Nazarene University) and Judy Green (Marymount University), "Cubes, Conic Sections, and Crockett Johnson," Loci (March 2014)

Dummy View - NOT TO BE DELETED