The extension Ladder illustrated in Figs. 1 to 3 will be found useful for light work. Three to four 8-ft. to 12-ft. lengths of straight-grained red deal, about 3 in. by 2 in., can be punted together, the wood being free from knots and oval in section. Oak or ash is suitable for the rounds, old wheel spokes often being used for this purpose. The iron (Fig. J) should he about | in. thick and 2 1/4 in. wide. These irons should be welded, and prepared with screw holes as shown. They are fixed with screws on the sides about three rounds from the top before the sides and rounds are fixed together. So that the ends of the lengths shall fit tightly into the irons, and at the same time be easy to release, they should be tapered a little, as shown at A and C (Fig. 1). To allow for this, the long dimension of the iron should be about Jin. less than that of the two sides.

Fig. 4.

Fig. 3. Making an Extension Ladder.