Details
Ertel & Sohn
A 19th century oxidised brass plane table surveying level, signed on the parallel rule Ertel & Sohn in München, the telescope with rack-and-pinion focusing, graduated bubble level, lens hood to the 1½in. (3.8cm.) object glass, the trunnion clamp with marbled finish, the axis with vertical semi-circular scale divided in silver 60°-0°-60°, the vernier arranged to swivel, the tapering vertical column with clamp, fine adjustment screws and cross-bubble level, the parallel rule with clamp and supplementary plane table graduated bubble - overall length 28 7/8in. (73.3cm.) (2)
A 19th century oxidised brass plane table surveying level, signed on the parallel rule Ertel & Sohn in München, the telescope with rack-and-pinion focusing, graduated bubble level, lens hood to the 1½in. (3.8cm.) object glass, the trunnion clamp with marbled finish, the axis with vertical semi-circular scale divided in silver 60°-0°-60°, the vernier arranged to swivel, the tapering vertical column with clamp, fine adjustment screws and cross-bubble level, the parallel rule with clamp and supplementary plane table graduated bubble - overall length 28 7/8in. (73.3cm.) (2)