Perspective, a series of elementary lectures (1899)
Cone, Ada · New York, W.T. Comstock · leaf 61
55 PERSPECTIVE. sought. Draw the nearest upright line of the object, A B, resting on the ground line. From each end draw lines to the Y. P. and they will be at an angle of 75° with the Gr. L. or Picture Plane. When the angle is not known, the direction of the retreating line may be determined by… … judging its direction by the eye. This gives the Y. P. for this line and all others parallel to it. Draw a line from B to the same Y. P. But now, in com¬ pleting the cube, it will be seen that whereas in parallel perspective all the retreating lines converged to one point, here they do not ; for…
Perspective · Drawing
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