LASSELL; William; 1799-1880; GBR

He made his fortune as a brewer and invested his resources in his new passion for astronomy and started constructing telescopes in 1820. Attracted by the planets, he made equatorial instruments: 11-inch reflector (F/12.5) in 1833, 24-inch reflector (F/10.6) in 1845 and a huge 48-inch in 1858. For these last two instruments, he built with NASMYTH's help a grinding machine to manage the weight of the metal mirrors. From Liverpool, he discovered Neptune's satellite Triton in 1846, and then two Uranus' satellites in 1851. Then, "competed" by William BOND, he decided to serach for better skies in the island of Malta with his 24-inch in winter 1852 and then with the 48-inch between 1861 and 1865. Lassel allowed his assistant MARTH to use the 48-inch when planets were invisible and the latter discovered 600 nebulae.