Jonathon Sisson (1690-1747) was Mathematical Instrument Maker to His Royal Highness Frederick, Prince of Wales, father of George III. He worked at The Sphere, Corner of Beaufort Buildings, Strand, London, and in 1731 he made the original of this armillary sphere for the Prince of Wales. It is the only known instrument to have a direct connection with Prince Frederick. It was deposited in the observatory by Queen Charlotte some time in the late eighteenth century. Until recently it was in poor condition, but has been conserved and is now on show in the Science Museum in London as part of the George III collection.