Beschreibung:

the circular brass base plate with centrally-pivoted rotating brass diametrical rule fixed with removable pin, a glazed circular recess for compass to lower part, the base plate finely engraved and chased with an elliptical grid overlaid with inscriptions in thuluth naming the geographical locations on the grid, vertical and horizontal axis denoting longitude and latitude, the elliptical grid surrounded by four cartouches filled with fine inscriptions in thuluth on stippled grounds with scrolling tendrils, the border with a series of further inscription-filled cartouches denoting the bearings, applied hinged sundial to upper edge, hinged latitude arc to left hand side, two applied splayed brass feet to upper side of reverse, the hexadecagonal wood box with hinged lid, silver hinges and clasp, entirely clad in rayskin, the interior with green velvet lining, further fitted museum archive box inscribed with inventory number 44.2014
22.5 cm. diam.; the box 25.5 cm. diam.