Mechanical drawing. Elementary and advanced (1910)
Reid, John S. (John Simpson), 1856- · New York, J. Wiley & sons; [etc, etc.] · leaf 123
Fig. 148,draw a tangent to the sphere at the point T. Through Tdraw TPh per. to AhG. From the point Ph drop a per. to P\Pv is the point of shade. Prob. 24.—To shade the elevation of a sphere with gradedarcs of circles. ORTHOGRAPHIC PROJECTION. IO9 First find the brilliant point and the point of…