This page needs to be proofread.
The height of a cylinder is the length of the axis, or the distance from one base to the other. If the axis be perpendicular, the cylinder is said to be upright.
Here, as in the cone, the laws of perspective change the circles into ellipses. The axes of the ellipses, and that of the cylinder, may be given in inches by the monitor.
(12)
19. Draw an upright cylinder. (fig. 12.)
20. Cut a cylinder by a section parallel to its base. (figs. 11 and 12v)
21. Make a cylinder whose axis shall be horizon- tal. (fig. 13.)
