细节
An oxidised-brass Abney-type surveying level and clinometer,
by E. SPRENGER BERLIN No. 6814, with bubble-level, fine rack and pinion adjustment, silvered quadrant scale, the telescope with pin-hole sight and cross-wires and prism arranged so that the horizontal bubble may be used in the vertical plane, on hinged support and staff mounting engraved with a horizontal circle and vernier, in leather carrying case -- 8.1/2in. (21.6cm.) wide
See Illustration
by E. SPRENGER BERLIN No. 6814, with bubble-level, fine rack and pinion adjustment, silvered quadrant scale, the telescope with pin-hole sight and cross-wires and prism arranged so that the horizontal bubble may be used in the vertical plane, on hinged support and staff mounting engraved with a horizontal circle and vernier, in leather carrying case -- 8.1/2in. (21.6cm.) wide
See Illustration