Description

A very unusual 6 inch square compass in flame mahogany, probably used for simple or plane table surveying by Thomas Bolton of Birmingham, England c.1820.

The thick and heavy case is perfect except for two brass hinge screws missing (see photo). It has some unusual features such as a solid brass plate on the right side and another brass plate on the bottom (probably to accommodate a Jacob’s staff head). Lately, it has been used as a pocket compass with 8 cardinal points on a near perfect silvered dial with outer raised ring from 0-360 degrees in one degree increments. The jewelled needle still points north and is locked by a pin when the lid is closed. The center of the glass has been drilled out to accommodate the pivot point when the needle is raised. Both heavy L-hooks are present. Weighs one kilo for postal consideration. Mahogany/rosewood case measures 6 x 6 x 1 1/2 inches.

Thomas Bolton was not a prolific maker of scientific instruments in Birmingham from 1810-30. An oddity.