Frames for the Cantilever Bridge.

[Illustration:  Fig. 305.  A Frame (make four).]

[Illustration:  Fig. 306.  B Frame (make four).]

[Illustration:  Fig. 307.  C Frame (make four).]

[Illustration:  Fig. 308.  D Frame (make four).]

[Illustration:  Fishing off the Cantilever Bridge.]

[Illustration:  The Cantilever Bridge in Reddy’s Back Yard.]

[Illustration:  Fig. 309.  E Frame (make four).]

[Illustration:  Fig. 310.  F Frame (make two).]

[Illustration:  Fig. 311.  G Frame (make two).]

[Illustration:  Fig. 312.  H Frame (make one).]

[Illustration:  Fig. 313.  I Frame (make one).]

[Illustration:  Fig. 314.  J Frame (make one).]

The frames with which the cantilever bridge was built were made of saplings from 3 to 4 inches in diameter.  We procured them from Mr. Schreiner’s lands up the river.  In making the frames the sticks were fastened together with 1/2-inch bolts 6 inches long.  It was quite a strain on our pocketbooks to buy these bolts, but Uncle Ed had written that nails or spikes would be useless to stand the strains of so large a bridge, and that if we could not get any bolts we had better give up the idea of building a cantilever bridge.  To make sure that we made no mistakes, Uncle Ed had made a drawing of each different size of frame we would need, designating each with a different letter, and then these same letters were marked on a general view of the bridge, so that we would know exactly where the frames belonged.  These drawings are reproduced here in Figs. 305 to 316 and 318.  We had to make four frames each, of the A, B, C and E sizes, two each of the F, G and I sizes and one each of the H, I, J and K sizes.  Of the D frames two were made with the ends cut away on the outer half, as illustrated in Fig. 308, and two were cut away at the inner side, the reason for which will appear presently.  When fastening the timbers together we cut notches in each stick, as shown in Fig. 317.  The depth of each notch was just one-quarter the diameter of the stick; that is, the notch was 3/4 of an inch deep in a 3-inch stick and 1 inch deep in a 4-inch stick.  Care was taken not to exceed this depth, for fear of weakening the sticks.  In the case of frame D, the sticks were not notched or mortised together.  It will be noticed that the measurements are given to the inner edges of the sticks in some cases, and to the outer edges in others.  The reason for this, as Uncle Ed explained it, was because the thickness of our sticks would vary considerably, and it was important that many of the measurements be exact, otherwise the frames would not fit into each other as they should.  Another thing to which he called our attention was the fact that frames A, B, E, F, H, K and L were stiffened with cross braces, while the rest were not.  The braced frames, he wrote, were those which would be under a compression strain, while the others would