Scientific American, Vol. 21, No. 18 (1869)
Scientific American, volume 21, number 18, a weekly American periodical of 1869 that printed technical inventions and mechanical engineering news for a general readership of inventors and mechanics. The pictures are line-engraved mechanical diagrams: a sectioned valve or pump body, a wheel-and-hub assembly, a locomotive-style frame, and a hand-held apple peeling tool, all drawn with dense hatching and lettered reference marks. A designer could draw on their crisp hatching patterns and the precise, labelled cutaway style of Victorian technical drawing.
