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 557
Fis. 23. letters of the bearing are alike, that is, both I^. or both S., and the last let-ters also alike, both E. or both W., the angle of deflection C B B will bethe difference of the bearings, or, in this instance, 20°.
