Dividers & CompassesBeam Compasses
Mechanical and architectural drawings have sometimes required circles with diameters of several feet instead of the several inches possible with a standard drawing compass. A beam compass was usually sold with just the points, which the user attached to the ends of a metal rod or wooden slat the length of the desired radius of the circle. One end was held in place, and the other end was pivoted around that end, maintaining contact with the paper. The patent model in the collection is a beam compass.
"Dividers & Compasses - Beam Compasses" showing 1 items.
- This steel instrument is plated with chromium and stored in a leatherette pocketbook case lined with purple velvet. The inside of the flap is marked: DIETZGEN. The back of the case is marked: GERMANY. The beam compass consists of a solid tubular beam, 13" long and 3/16" in diameter; a second solid tubular beam, 6" long and 3/16" in diameter; a coupling for joining the beams with a thumbscrew; a needle point with a micrometer adjustment; a second needle point; a pencil point; a pen point; and a cylindrical case holding one extra lead and two additional needles. The handles on the points are cylindrical with a honeycomb pattern. The thumbscrew on the needle point with micrometer is marked: DIETZGEN GERMANY.
- The Eugene Dietzgen Co., a Chicago manufacturer and retailer of mathematical instruments, advertised the model 967A "Champion" brand beam compass and case in the late 1930s for $8.50. Dietzgen may have purchased instruments in the Champion line from Bayerische Reisszeugfabrik, a company in Nuremberg, Germany, that was owned by Joseph Dietzgen and made ECOBRA brand slide rules. See 1984.1071.04.
- References: Catalog of Eugene Dietzgen Co., 15th ed. (Chicago, 1938), 141; Dietzgen Essential Drawing Instruments and Materials, cat. no. 38A (Chicago, ), 11.
- Currently not on view
- date made
- ca 1938
- ID Number
- accession number
- catalog number
- Data Source
- National Museum of American History, Kenneth E. Behring Center