Omicron Bow Compass

This aluminum and metal bow pencil has a ring connecting the instrument to its cylindrical handle, which has a honeycomb pattern. Its width is adjusted by a metal disc between the legs, but the pin holding the disc extends through only one leg of the compass. A ball is on the end of the pin. A rusted lever is on the pin between the legs. The legs are open and hollow. Thumbscrews on the front of one leg and the back of the other adjust the pencil and needle points. The needle point is only pointed on one end; i.e., it is not reversible. Inside each leg is engraved: OMICRON GLENDALE CAL.
Omicron manufactured drawing instruments, such as ellipsographs, in Glendale, Calif., in the 1940s and 1950s. Robert Behrens Condon studied engineering at the University of Vermont and Columbia University in the late 1940s and early 1950s, which is probably when he purchased this instrument. He operated the New Englander Motor Inn with his politically active wife, Marie, from 1955 to 1978.
Reference: "April Milestones 2012," Friends Journal,
Currently not on view
date made
mid 20th century
place made
United States: California, Glendale
Physical Description
steel (overall material)
aluminum (overall material)
overall: 18.4 cm x 6.9 cm x 1.4 cm; 7 1/4 in x 2 23/32 in x 9/16 in
ID Number
accession number
catalog number
Credit Line
Gift of Robert B. Condon
Drawing Instruments
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Dividers and Compasses
Data Source
National Museum of American History


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