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 496
F-- … JB r 1^ ll!ll:lili|ii!J K f 0 i AJi D ^ c m ^mi SHADING AND SHADOWS. 319 perpendicular from tlie opposite point D, because it is altogether con-cealed in the vertical elevation of the solid. In order to ascertain thepoints C and D with accuracy, draw through the centre O a diameterperpendicular to…