The Troughton telescope Bought: 1807 Company: Troughton, London

The 5-foot telescope with the 3.5 inch achromatic objective allowed to carry out serious observations: in the years 1819-1822 it was W. Struve’s main observational instrument. The small relative aperture and unstable control limited the possibilities of use. The Moon and planets were the main objects of observation. When in 1814 the ocular micrometer was obtained, Struve began to observe binary stars with this instrument. It was good training for the future work with the Fraunhofer refractor. After the arrival of the Fraunhofer telescope it was used episodically. In 1927 it became the guide of the Petzval camera separated from the Zeiss refractor.

Edward Troughton (1753-1835). Having started his work at the workshop of his uncle John Troughton, Edward became one of the most famous apparatus builders in Europe, in the end of the 18th century. In Troughton’s workshop sextants, barometers, theodolites and other instruments necessary for a maritime country were made. Edward became known primarily for making astronomical apparatuses among which best known are the transit instruments for the Greenwich observatory and the equatorial telescope of the Armagh observatory from 1795, the predecessor of the big telescope of today – which has survived until today.

Observation register of professor Pfaff (TO)