Telescope speculum grinding tool for Lord Rosse's 72-inch telescope at Birr Castle, Ireland mb-artistname William Theed the centaur

the centaur

Bloomsbury Way

the Conservatives Lord Derby (with the glasses) and Disraeli have come to pay a social call on the Liberal Prime Minister

pictured at the Royal Ballet rehearsal rooms

Telescope speculum grinding tool for Lord Rosse's 72-inch telescope at Birr Castle, Ireland mb-artistname William Theed the centaurPlate 24 figure 4 from the paper "On the construction of specula of six feet aperture; and a selection from the observations of nebulae made with them", by William Parsons, 3rd Earl of Rosse, Philosophical Transactions of the Royal Society, volume 151 (1861) pp. 681 746. A front view of the cast iron grinding tool used to produce the speculum of the reflecting telescope at Birr Castle, Parsonstown. The face has straight cast grooves forming squares