Jason Clarke Antiques has dated this piece to the 1800s.
The telescope has a 2” objective lens with screw on dust-cap with slide opening and an extending sun-shade which pulls from the barrel end. The eyetube has a typical period bell-shaped eyepiece with incorporated dust-slide and the first draw is engraved to the maker, Thomas Rubergall, Optician to His Majesty, 24 Coventry Street, London.
The maker Thomas Rubergall was active from 1802 until 1854 in London and traded from three different addresses throughout those 52 years. Princes St, Soho from 1802 to 1805, 27 Coventry Street from 1805 to 1823 and then thereafter to number 24 Coventry Street. Rubergall seems to have been from Huguenot French descent and may be related to earlier well-known Chelsea market gardeners of the eighteenth century with the same name. He was renowned enough to have been appointed optician to George III and mathematical instrument maker and optician to the Duke of Clarence (later William IV) and to Queen Victoria.
The site of the Rubergall’s shop was situated between Piccadilly and Leicester Square.
A superbly executed instrument from one of the most prominent scientific instrument retailers of the first half of the nineteenth century. The dating of this instrument can be reduced to a fourteen year period between 1823 & 1837 which relate to the dates that Rubergall began trading from the 24 Coventry Street address and the death of William IV (note the ‘His Majesty’ inscription). Given the trading address dates, the reference to His Majesty could very well mean George IV but I suspect slightly later due to the style of the eyepiece and also the fact that Rubergall from the various examples that I have come across, seems to have maintained a very close relationship with William IV as a patron.
Circa 1830
Jason Clarke Antiques has dated this piece to the 1800s.
You can view the stock and full dealer information on the Jason Clarke Antiques Profile Page
William IV Two Draw Telescope by Thomas Rubergall London
