Apprenticed in a merchant's office in Liverpool and in 1835 set up as a brewer. In 1820 he began to construct telescopes and in 1840 built an observatory at Starfield near Liverpool. He ground and polished a speculum of rare perfection two feet in diameter and in 1846 discovered the solitary satellite revolving round Neptune. In 1848 he discovered Hyperion the 8th satellite of Saturn. F. R. S. 1849. Royal Medal 1858. The composition of the Uranian system was first clearly ascertained by Lassel. Erected a large telescope at Valetta, Malta and made valuable observations with it. On returning to England he set up an observatory near Maidenhead.
From the description of Items in various series of The Royal Society, 1842-1875. (Unknown). WorldCat record id: 83343143
