Appleton's cyclopædia of drawing, designed as a textbook for the mechanic, architect, engineer, and surveyor (1866)
Worthen, William Ezra, 1819-1897, [from old catalog] ed, Appleton, firm, publishers, New York. (1866. D. Appleton & co.) [from old catalog] · New York, D. Appleton and company · leaf 54
the given angular point,if the instrument was first correctly set. In this manner, at one setting ofthe instrument, a great number of angles may be laid off from the samepoint. It is not essential that the centre be over the given point, when appliedto the given line, provided the pricking points… … the same scale, on a reduced scale, or on an enlarged scale, as may be re-quired. It is represented (fig. 77) as in the act of copying a plan H, upon3 34: DEAWING INSTRU:MENTS. a reduced scale li. The pentagraph consists of four rulers, A, B, C, and D,made of stout brass. The two longer rulers, A…
