Page:Popular Science Monthly Volume 8.djvu/109

Rh To proceed, make a rod, like an ordinary ruler, 13½ inches long, and of the diameter of Fig. 4. Now turn, or get turned, a tube, 4½ inches long, the walls of which shall be ¼ of an inch thick; Fig. 5 will give the diameter.

A part which I call the cradle can now be made; the form is shown in section, at Fig. 6; its length must be 3¾ inches.

The support for the stage requires no special explanation; a full-sized drawing is given at Fig. 7.

The stage itself can be made of wood, but gutta-percha is better,



and, if placed in hot water, it can afterward be easily moulded to the pattern given at Fig. 9.

Smooth the surface while still warm with glass plates, and steady the back with two strips of wood. The shaded part at the lower edge shows a piece of wood fixed thereon to support a zoöphite trough or glass slides. Fig. 10 represents the upper and lower parts of a leg, two of which are required, 9¾ inches long, and the size shown in cut. On the upper portion the brass hinged attachment is fixed.

The appearance of the paper tube, with eye-piece and object-glass in position, can be seen at Fig. 11.