Azimuth compass

This dry card compass has a paper card (diameter 8.25 inches) marked in points and degress (0-90 in each quadrant). In addition there is a metal rim, also marked in degrees. The card is printed with the name of the inventor, Thomas Smith, and of the maker, George Adams. In addition, the name of a retailer, T. Blunt, has been pasted onto the bottom of the card. The needle is an ordinary flat bar magnet with a sliding weight for balancing. The bowl is fitted with an adjustable stop for checking the movement of the card, this having some vertical lines engraved on it, apparently for use as lubber lines.

Object Details

ID: ACO0003
Collection: Astronomical and navigational instruments
Type: Azimuth compass
Display location: Not on display
Creator: Adams, George
Date made: 1791
Credit: National Maritime Museum, Greenwich, London, Admiralty Compass Observatory
Measurements: Overall: 339 mm x 340 mm x 297 mm; Diameter: 273 mm