showingthin.gs
YOUR NEXT DISCOVERY/ArtifactsFollow your curiosity

United States: Maryland, Frederick / Date unspecified

Surveyor's Vernier Compass

Surveyor's Vernier Compass

The Smithsonian catalogs Surveyor's Vernier Compass as surveyor's compass in its Revolutionary War records.

WHY IT’S INTERESTING

The variation arc on the south arm of this surveyor's compass extends 14 degrees to either side; the vernier is moved by hand, and reads to 6 minutes. The bottom plate is not solid, as was usually the case, but has six large segments cut out, presumably to save brass and/or reduce the weight of the instrument. The compass face reads clockwise--a feature that was probably introduced at the behest o

SERENDIPITYA little unexpected
FamiliarWeird

A CLOSER LOOK

The Smithsonian lists the object under Revolutionary War.

The variation arc on the south arm of this surveyor's compass extends 14 degrees to either side; the vernier is moved by hand, and reads to 6 minutes. The bottom plate is not solid, as was usually the case, but has six large segments cut out, presumably to save brass and/or reduce the weight of the instrument. The compass face reads clockwise--a feature that was probably introduced at the behest o

FOLLOW THE EVIDENCE

Smithsonian InstitutionSurveyor's Vernier Compass

Original explanation based on the sources above. Images carry their own reuse terms.