Universal ring dial, by Adams; in mahogany case, no key, engraved made by Geo Adams at tycho brake's head in Fleet Street, London brass with silvered scales, diams of vertical divided circle 9" horizontal and vertical circles divided in degrees, and reading to vernier by 5' hour circle divided to 2 min, 3 levelling screws hole sights fixed to vertical circle, slow motion by pinion for both vertical and horizontal circles Universal ring dial 1734-1796