The Kidjel Ratio System Instruction Manual

The citation information for this spiral-bound book is: Maurice Kidjel, The Kidjel Ratio System 5.333/1 (Honolulu, 1962). It was received with an example of Kidjel's Cali-Pro proportional dividers (MA*333876), and a warranty card for the Cali-Pro is inside the front cover of the book. After a biographical note, Kidjel provided supposed solutions to the three classic construction problems of Greek antiquity (trisecting the angle, squaring the circle, and doubling the cube).
Although the Cali-Pro was not needed for these attempted solutions, in part two of the book Kidjel explained how to make these and other, more standard, solutions with the device. Next, he discussed how his ratio applied to the human body. Finally, he explained how to use the Cali-Pro in various fields of industrial design, such as architecture and publishing. A brief biography of Kidjel's business partner, Kenneth W. K. Young, is found inside the back cover. The back cover reproduces a portion of then-U.S. Representative Daniel Inouye's remarks about the Kidjel ratio system, read into the Congressional Record of the 86th Congress.
Currently not on view
Object Name
date made
Kidjel, Maurice
Young, Kenneth W. K.
Physical Description
paper (overall material)
plastic (overall material)
overall: 23.3 cm x 16 cm; 9 3/16 in x 6 5/16 in
Place Made
ID Number
accession number
catalog number
Science & Mathematics
Drawing Instruments
Mathematical Cranks
Dividers and Compasses
See more items in
Medicine and Science: Mathematics
Dividers and Compasses
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Transfer from U.S. Department of the Treasury, Internal Revenue Service, Publications Department
Additional Media

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