1-158-367 - Oxford Science Archive/Heritage Images

Lord Rosse's 72 in/1.8m reflecting telescope, 1849. William Parsons, 3rd Earl of Rosse (1800-1867), Irish astronomer and engineer, built what was then the largest telescope in the world on his estate at Parsonstown, Ireland. With it he discovered 15 spiral nebulae, and named the Crab nebula. From his paper On the Construction of Specula [mirrors] of Six-feet Aperture ... from Philosophical Transactions of the Royal Society. (London, 1849).