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 205
includes a varietyof pitches from | inch up to 3 inches, according to the following table,which shows the value of the circular pitches corresponding to the assignedvalues of m. Values of m. 1 2 3 4 5 6 7 8 9 10 12 14 16 20 Corresponding circular pitch in deci- \mals of an inch, f 3.142 1.571 1.047… … adopted as tlio tci-m of comparison. Tlie following are the proportionsadopted by dilfcrent workshops, some preferring one and some the other(fig. 2Cfi). 1 pitch, or = 15 parts, _3_ ii 1 0 = 5i G a 1 0 u ^ 11 u ro i^ = I u r o u ^ 12 r\ - = 7 i^- ^ - 8 DEAWING OF MACHINERY. 1G3 A C = Pitch of…
