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 instrument consists of a wooden beam and a single German silver trammel with a micrometer and needle point. A large round hole in one end of the beam allows the instrument to be hung. The other end of the beam is marked in pencil at each of the first six inch points. The trammel is similar but not fully identical to Dietzgen's model number 646, which sold with a pair of trammels, two needle/pencil points, and a pen point for $9.20 in 1904–1905. This instrument was owned by the renowned American designer of steam engines, Erasmus Darwin Leavitt Jr. (1836–1916), and donated by his granddaughter, Margaret van D. Rice.
- Reference: Catalogue & Price List of Eugene Dietzgen Co., 7th ed. (Chicago, 1904), 71.
- Currently not on view
- date made
- ca 1900
- ID Number
- accession number
- catalog number
- Data Source
- National Museum of American History, Kenneth E. Behring Center