Standing universal equinoctial ring dial for all latitudes. Standard universal equinoctial ring dial (see related terms) except for the following details:-

The dial is mounted on a circular base, supported by three turned levelling screws. A silvered compass is set into the base along with two brass bubble levels. Two small supports hold the collar of the meridian ring, within which the meridian ring is free to move, to adjust it for latitude or to make altitude observations. On the bridge, the equinoxes are marked at 21 March and 23 September. The maker's signature: 'Thos. Heath Strand Londini Fecit', can be found on the base.

This 'standing' dial is similar to ordinary universal equinoctial ring dials, but can be oriented by means of the compass if the magnetic variation is known. Alternatively, the self-orienting nature of the dial means that it can be used to find the variation once the dial is correctly oriented. Two similar instruments are in the Whipple Museum (accession nos. Wh: 0968 and Wh: 0151) and one also in the MHS, Oxford (new inventory no. 78442).

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