Telescope

This Galilean telescope has the name 'IACOB CUNIGHAM' and the date '1661' stamped onto the objective lens cap, making it one of the oldest dated telescopes in Britain.

The two draw tubes are made of wood covered in marbled vellum, while the barrel and lens caps are made of wood covered in red leather with gold-tooled decoration. The eyepiece tube also has three gold-tooled extension marks identified by the German (or 'Dutchified' versions of German) words 'NAHE' (near), 'WEITH' (far) and 'OVERSICHTIG' (farsighted/hyperopic). These lines indicate different focusing lengths. Jacob Cunighamseems to have been the original owner of the telescope. The larger draw tube also has a single gold-tooled stop line.

The curious shape of the barrel is designed to accommodate a large objective glass. At this time it was easier to grind a large lens than a small one. Brass diaphragms over the end of each lens have been used to reduce their apertures.

Object Details

ID: NAV1547
Collection: Astronomical and navigational instruments
Type: Portable telescope
Display location: Display - QH
Creator: Cunigham, Jacob
Date made: 1661
Credit: National Maritime Museum, Greenwich, London, Caird Collection
Measurements: Length: 325 mm (closed, with caps), 688 mm (open, to stop lines, max); diameter: 92 mm (max)
Parts: Telescope