This achromatic telescope has a mahogany barrel and three brass draw tubes. The other brass fittings include an objective lens cap. The original case, made of card, still survives, although it has clearly been repaired at some time. The maker's name is inscribed on the smallest draw tube as 'GILBERT & CO LONDON'.

A piece of paper inside the case claims that this was a 'Telescope used during Captain Cook's last voyage by Lieut Gilbert (Gilbert Islands) - my mother's great uncle'. It is more likely, however, that the telescope was made after the date of Cook's third, and final, voyage (1776-9).