This achromatic telescope has a tapering leather-covered barrel and silvered-brass fittings, including a single draw tube, a sliding sunshade and a pivoted eyepiece cover. The objective lens cap is missing and the leather covering is now badly damaged.

The maker's name is inscribed on the draw tube as 'Gieves Ltd. No. 8890', with the owner's name engraved on the collar of the barrel. In addition, the number XII is roughly inscribed in a number of areas, presumably as part of the manufacturing and assembly of the item.

The telescope formerly belonged to Terence Thornton Lewin (1920-99). Lewin entered the Royal Navy in 1939 and served in the Home and Mediterranean Fleets, Malta and North Russian convoys and the invasion of North Africa. Among other commands after the Second World War, he was Commander, HM Britannia (1957-58), commanded HMS 'Hermes' (1966-67), subsequently becoming First Sea Lord. He was Chief of Defence Staff during the Falklands War, 1982. Lord Lewin later served as Chairman of the Trustees of the National Maritime Museum (1987-95).