In 1688, the Frenchman Louis Lucas de Nehou, in conjunction with Abraham Thevart, succeeded in perfecting the process of casting plate-glass.
Mirror plates prior to the invention had been made from blown "sheet" glass, and were consequently very limited in size.
De Nehou's process of rolling molten glass poured on an iron table rendered the manufacture of very large plates possible.
[2] In 1773 English polished plate (by the French process) was produced at Ravenhead.
By 1800 a steam engine was used to carry out the grinding and polishing of the cast glass.