The practical draughtsman's book of industrial design and machinist's and engineer's companion : forming a complete course of mechanical, engineering and architectural drawing (1866)
Armengaud, M. (Jacques Eugène), 1810-1891, Armengaud, M. (Charles), 1813-1893, Amouroux, M. (Jules), Johnson, William, 1823-1846 · Philadelphia : H.C. Baird · leaf 202
Fig. 30. an uneven outline. In the instrument represented in figs. 29 and30, the parts which traverse the guide-grooves in the plate, q, con-sist of small steel wheels, o, p, carried in the forked ends of the * See page 17. steel spindles, o, p, which are entered loose into the socket legs,o, p.… … Fig. 32 tion with regard to the grooves, whatever be the position of the bar,e, and pen, s. In adjusting the instrument, it is simply necessaryto set the pen and centre legs, so that the distance of the twolatter from the former shall correspond respectively with thesemi-transverse and…
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