US Patent 908.519, Type-Casting Machine
This is a US patent specification, number 908,519, filed by John S. Thompson in 1908 and granted in 1909, describing a type-casting machine for printing type and sorts. The pictures are black-and-white mechanical patent drawings with numbered reference lines and figure labels, showing assemblies of levers, moulds, and gears in several views. A designer can take from them the schematic conventions of early engineering drawing: leader lines, lettered callouts, and clean line work on a white ground.
