Scientific American, Vol. 21, No. 7 (1869)
Scientific American, volume 21, number 7 from 1869, a weekly American periodical of mechanical and scientific news aimed at inventors, engineers and general readers. The pictures are black-and-white wood engravings of machines, with plain line drawing, hatched shading and labelled parts, showing how each device is built and operated, which suits designers studying nineteenth-century mechanical diagrams.
