BornMoor Lane, Bolton, (Greater Manchester), England, 18 June 1799
DiedMaidenhead, Berkshire, England, 5 October 1880
William Lassell constructed the first large equatorially mounted reflecting telescopes and proved both the viability and the utility of such large instruments. Using his large reflectors, Lassell discovered several satellites of the outer planets.
The son of Nathaniel Lassell, a timber merchant and Hannah (née Gregson) Lassell, William was raised in middle-class comfort in a distinctly commercial extended family. He began his education at an elementary school in Bolton and then, at the age of about nine, he entered an academy in Rochdale, Lancashire where Lassell remained for one and a half years. His father died in 1810 while he was still attending school. He started an apprenticeship as a commercial trader in 1814, and by about 1825 he had established himself as a partner in a Liverpool brewing business. Soon afterward, in 1827, he married Maria King of Toxteth.