Mechanical drawing. Elementary and advanced (1910)
Reid, John S. (John Simpson), 1856- · New York, J. Wiley & sons; [etc, etc.] · leaf 125
Fig. 151. Fig. 152. The mixed appearance of the lines near the apex of thecone on Fig. 151 can usually be avoided by letting each linedry before drawing another through it, or as some draftsmendo, stop the lines just before they touch. Prob. 2j.—To shade the concave surface of a section of a hollow… … ORTHOGRAPHIC PROJECTION. Ill SHADOWS. Let Ry Fig. 154, be the direction of the rays of lightand C an opaque body between the source of light and a
