gimballed magnetic compass with arm
Date: 19th Century
Inventory Number: DW0135
Classification: Magnetic Compass
Subject:
Cultural Region:
Dimensions:
24.6 × 10.8 × 3.7 cm (9 11/16 × 4 1/4 × 1 7/16 in.)
Description:
Gimballed brass compass in round frame with a rectangular arm.
The compass needle is thin, with a split tail and an arrow-shaped point. Engraved on the silvered face are two perpindicular lines whose ends are marked: M, P, T, and L.
Engraved on the frame are two lines: the center line, lengthwise, and a horizontal line near the compass end. There are two holes in the arm along the center line near the compass end.
Visible on the back of the arm are two bolts attaching the arm to the round frame, as well as two bolts behind the compass. At the center of the back of the compass is a screw with an oval knob.
The compass needle is thin, with a split tail and an arrow-shaped point. Engraved on the silvered face are two perpindicular lines whose ends are marked: M, P, T, and L.
Engraved on the frame are two lines: the center line, lengthwise, and a horizontal line near the compass end. There are two holes in the arm along the center line near the compass end.
Visible on the back of the arm are two bolts attaching the arm to the round frame, as well as two bolts behind the compass. At the center of the back of the compass is a screw with an oval knob.
Signedunsigned
FunctionFor determining direction with respect to the earth's magnetic poles. The compass is hung in gimballs, allowing it to remain flat despite changes in the frame's inclination.
Curatorial RemarksIt is unclear whether this compass was used for surveying or navigation. See two similar compasses, DW0134, DW0136.