Scientific American, Vol. 25, No. 9 (1871)
Scientific American, volume 25, number 9, published in New York in 1871, is a weekly American periodical written for engineers, inventors and mechanics. Its pages here carry wood-engraved line drawings of a tunnel or drainage section, a magazine breech-loading rifle with numbered figures, and a clamping device with three views. Designers can draw on the precise figure-numbered diagram style, with lettered callouts and clean hatching for showing internal mechanisms.







