Speculum; the Latin word for mirror. Ancient mirrors were made from this alloy (70%Cu, 30% Sn). Sir Issac Newton, in 1668, turned to this alloy when he developed his reflecting telescope design. This mirror was made from bronze that was originally sourced from a bell that was made by Thomas Lester (now Whitechapel Bellfoundry) in 1728. It was this same Lester, with Pack, that cast our first Liberty Bell in 1752.