Wollaston, William Hyde (1766-1828), an English chemist and physicist. In 1802 Wollaston discovered the dark lines in the solar spectrum (later named Fraunhofer lines). The following year he invented a method for producing platinum in malleable form and discovered two metallic elements: palladium and rhodium. In 1809 Wollaston invented the reflecting goniometer, a device for determining the shapes of crystals. Another of his inventions, in 1812, was the camera lucida.