with a small screw passed through a hole punched near its end, and through the hole near the folded end of plate C. Fasten plate B with a rug-tack (F) so the lever will come in contact with it. Screw-eyes E form the binding-posts.
Instead of using a separate base, the switch can be mounted as shown in Fig. 176, upon the base of
The Derrick. Cut the base about 8 inches wide and 10 inches long (A, Fig. 176). The mast (B) is a piece of broom-handle or curtain-pole 16 inches long, and fits loosely in a hole bored in the base. Figure 183 shows a detail of the mast. The pulley upon its upper end (C) is made of two spool-ends nailed together (Fig. 184), and it turns upon the axle D, which slips through holes in the plates E nailed to the end of the mast.
Fig. 183.—Detail of Mast.
Fig. 184.—Detail of Pulley.
Fig. 185.—Detail of Boom.
The lever F sticks in a hole in the mast, close to the platform. This is used to swing the boom from side to side. Screw-eye G is placed several inches above F to serve the purpose of a pulley to guide the hoisting cables.
