Transit telescope

This is an early transit telescope in lacquered brass made by Thomas Cooke and Sons of London and York. They specialised in surveying instruments and made several transit telescopes like this one some of which are in the Royal Observatory collection. It may have been acquired for the University Observatory which was on Woodhouse Moor near the old Grammar School until the second world war when it was demolished. It is in very fine condition and has very precise adjustments to enable it to be aligned correctly. Several parts are missing: the telescope eyepiece, one of the magnifiers on the vernier scale and a spirit level for which there is a mount. It is very heavy, weighing about 35 kg. Thomas Cooke later amalgamated with Troughton and Sims and formed the company Cooke, Troughton and Sims who had a factory in York and made many fine optical instruments – mostly microscopes and telescopes. They and another microscope manufacturer – Baker of High Holborn, London – were eventually subsumed in Vickers instruments in 1963 who continued manufacture in York for a number of years. York University has a museum devoted to Cooke, Troughton and Sims products.