Butterfield dial for latitudes 40°-60° North. Standard four-scale dial (see related terms) except for the following details:-

The scales are for 55°, 50°, 45° and 40°. The compass is offset 17° West of North to allow for magnetic variation, and the cardinal and quadrantal points are marked in French. A line is scratched further west, possibly for a new magnetic variation. The glass plate over the compass is chipped. The gnomon is detached at the centre of the dial. On the compass base (which is very badly scratched) and the reverse side of the dial-plate is a table of latitudes, on which are places such as 'Varsovie (Warsaw) 52', 'Vienne 48' and 'Rome 42'.

The dial has an unusually large black leather case with red velvet, red and white damask lining and two brass hook fasteners. It is clearly not that which was supplied with the sundial. All other existing cases are close-fitting and echo the shape of the sundial itself. This one was probably made at a later date. The inclusion on the dial of a scale for a latitude of 55° is not common on Butterfield dials and perhaps reflects the inclusion of some high latitude towns in the table (Gdansk and Hamburg). It is signed 'N Bion A Paris'.

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