细节
An oxcidised brass "Hezzaninth"-pattern sextant
the arc signed Heath & Co. Ltd. Crayford, London, N187 , further engraved J.G.G. Dugdale, R.N., with silvered scale, the 'bell' frame with adjustable telescope mounting socket, seven shades, mirror with glare reflector, the index arm with vernier and magnifier, tangent screw fine adjustment with clamp, mahogany handle, four telescopes, accessories and instruction leaflet in mahogany case -- 10.7/8in. (27.7cm.) wide
See illustration
the arc signed Heath & C
See illustration