Compass dial for latitude 48° North. This is a round gilt-copper fob sundial with a suspension ring for attachment to the fob chain. The back of the instrument is blue enamel. Convex glass covers both the compass and the dial-plate, which is supported by three equidistant radial gilt-copper struts. The plate and the compass are both made of white enamel with black enamel markings. On the plate is an hour scale numbered clockwise VI-XII, I-VI, and a silvered brass shaped gnomon.

The compass has eight points, marked by French initials, and a magnetic variation scale, divided anticlockwise 10°-[35°]. The variation scale starts at 5° West of North, not 10° as marked. The Meridian line is also marked. The needle, blued at its North end, has a crosspiece to further indicate North, and is surmounted by a brass pyramidal pivot. The enamel is chipped in two places revealing the copper beneath. The cover is hinged and can be opened. The dial is signed 'Armand AParis'.

This is the only known surviving instrument by Armand, who was active in the Founders' Corporation of Paris between 1755-80. The use of copper in sundials is uncommon but seems to have had some popularity with French (see AST0160) and Italian makers.

For more information regarding this dial please refer to the OUP & NMM catalogue, 'Sundials at Greenwich'.