Telescope speculum for Lord Rosse's 72-inch telescope at Birr Castle, Ireland Size:L: 70 x 70cm Sir John Whittaker Ellis

Sir John Whittaker Ellis

A rooftop view looking down on the Statue of Eros

with the monocle

December 1971

Telescope speculum for Lord Rosse's 72-inch telescope at Birr Castle, Ireland Size:L: 70 x 70cm Sir John Whittaker EllisPlate 24 figure 1 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 view of the speculum on supporting levers supported on a cast iron rail carriage. The carriage is shown on a turntable situated to the north side of the 72 inch reflecting