United States: Pennsylvania, Philadelphia / 1945-ca 1952
Alteneder 1666 Beam Compass
Alteneder 1666 Beam Compass
The Smithsonian catalogs Alteneder 1666 Beam Compass as beam compass in its Mathematics records.
WHY IT’S INTERESTING
This instrument has two very tarnished flat metal bars, each 22 cm long, with tapered ends that interlock to make a beam of 40.9 cm. The two steel sliding trammels resemble pencils and are marked: T.A. & SONS. The longer trammel has a needle point, and the shorter has a pencil point. The shorter trammel has a cam wheel that allows adjustment up to 3/16". Spring tension in both trammels may be adju