Geometrical drawing, projection drawing, freehand and ornamental drawing, wash work and brush drawing, elementary perspective drawing, architectural drawing (1921)
International Correspondence Schools · Scranton, PA : International Textbook Co. · leaf 283
les and are of the same length, but their apparent sizeson the picture plane fghj, as viewed by the eye at c, aredifferent; the line cd. being nearer the eye, appearing larger,as shown at c d. From this, the following rules may bededuced: Rule I.—The length of any line seen on the picture… … Fig. 3 Thus, in Fig. 3, a b being double the distance from e thatc d is, appears only one-half the size of cd on the pictureplane f ghj, as shown at a d; and the area of the rectangleah Ik appears on the picture plane only one-fourth the areaof the rectangle c d n m, as shown at a d I ¥, as each of
