This telescope has a tapering mahogany barrel and a single brass draw tube. The other fittings are also made of brass and include sliding objective and eyepiece lens covers, although the slide from the objective cover is now missing. A black stop line marked on the draw tube indicates the optimum working length of the telescope.

This telescope has an achromatic objective lens. The achromatic lens eliminated the problem of coloured fringes caused by the distortion of the light as it passes through the lens (chromatic aberration).

The London instrument maker John Dollond (1706-61) first took out a patent for this type of lens in 1758, having begun to make achromatic telescopes in 1757. Dollond's firm held the patent for 14 years, so this is a fairly early example of an achromatic telescope by a rival London firm. The maker's name is engraved on the draw tube: 'GREGORY & WRIGHT'S / Improved Telescope / LONDON'. The name 'Improved Telescope' refers to the fact that it incorporates an achromatic lens.