The instrument consists of a hinged lid and a box with a suspension ring which also serves as a lock for retaining the lid.
The outer face of the cover is decorated with an engraved urn, flowers and foliage. Its sides carry a leaf pattern.
The inner face of the cover has the signature '15 [star] M [star] P [star] 97' and the edges of the plate identify the cardinal directions as 'SEPTENRIO', 'ORIENT', 'MERIDIES' and 'OCCIDENT'. A circular scale of hours 1 to 12, 1 to 12, divided to 1/2 surrounds a wind rose star and a rotating index is fixed at the centre. The purpose of the hour scale is uncertain.
The main box carries a horizontal string-gnomon sundial with a decorated folding gnomon support which is sprung to the vertical and incorporates a plummet. Two soldiers with lances appear on one side of the support. The hours on the dial plate run from 4 to 12 to 8 with additional lines for the half hours. The latitude of use is given as 'P: 48 G:'. The inset compass is 21 mm in diameter and its slivered bowl is marked for the variation.
The sides and base of the main box are decoratively engraved.
Provenance: Lewis Evans Collection G. 363.