A rare small sized vernier 'A' frame sextant, with built-in gyroscopic artificial horizon, with barometric dial unit, below and to the left of the horizon mirror, signed on the silvered arc Hurlimann, Ponthus & Throde Succ. A Paris, 2679. the index arm with vernier, magnifier and locking clamp, sun inverting telescope on sliding attachment with five shades, mirrors, with mahogany handle in fitted mahogany case with accessories - 12in. (30cm.) wide.