Physical description

Thorpe’s Transparent replica of Rowland Metal Diffration Grating; 14,484 lines/inch. Consisting of glass rectangular specimen, approx. 5 x 3.5 cm stored in hinged black velvet lined box . Grating = 98.1 Box = 98.2

Inscriptions & markings

Label on grating: “The Surface of the grating must not be touched”. “THORP’s Transparent Replica of Rowland Metal Diffraction Grating 1st Q 14484 lines to the inch”