Dietzgen 1626 Triangular Open Divided Architect's Scale

This 12-inch triangular boxwood rule has indentations along each side. On one side, one edge has a scale divided to 1/16" and numbered by ones from 0 to 12. The other edge has scales for 3/32" and 3/16" to the foot. Between these scales is a scale divided to 3/32", numbered from left to right by fours from 0 to 124, and numbered from right to left by twos from 0 to 62. This side is marked: 1626 DIETZGEN U.S. ST'D.

One edge of the second side has scales for 1/2" and 1" to the foot. Between these scales is a scale divided to 1/2", numbered from left to right by twos from 0 to 20 and from right to left by ones from 0 to 10. The other edge has scales for 1/8" and 1/4" to the foot. Between these scales is a scale divided to 1/8", numbered from left to right by fours from 0 to 92 and from right to left by twos from 0 to 46.

One edge of the third side has scales for 3/8" and 3/4" to the foot. Between these scales is a scale divided to 3/8", numbered from left to right by twos from 0 to 28 and from right to left by ones from 0 to 14. The other edge has scales for 1-1/2" and 3" to the foot. Between these scales is a scale divided to 1-1/2", numbered from left to right by ones from 0 to 4 and from right to left by ones from 0 to 2. Some of the numberings are inside the indentations, similar to 1981.0933.11.

The Eugene Dietzgen Company sold model 1626 from at least 1904, when it cost 90¢, to at least 1926, when it cost $1.20. William J. Ellenberger (1908–2008), who donated this object, studied electrical and mechanical engineering at The George Washington University between 1925 and 1934. He then worked for the Potomac Electric Power Company and the National Bureau of Standards. During World War II, he served in the U.S. Army Signal Corps. He was a civilian construction management engineer for the army from 1954 to 1968, when he became a private consultant.

References: Catalogue & Price List of Eugene Dietzgen Co., 7th ed. (Chicago, 1904), 160; Catalogue & Price List of Eugene Dietzgen Co., 12th ed. (Chicago, 1926), 168; "The GW Engineering Hall of Fame 2006 Inductees," http://www.weas.gwu.edu/ifaf/hall_of_fame_inductees_2006.php.

Currently not on view