Part 18 (1/2)
THE ELASTIC BELLY BAND.
An important change was made in the belly band of the kite. The lower strand was made elastic by tying it fast to a number of heavy rubber bands, as in Fig. 242. When flying the kite, if a sudden, strong puff of wind struck it, the elastic belly band would give, tilting up the lower end of the kite so that the wind pa.s.sed under; but as soon as the gust had pa.s.sed the rubber bands would draw the lower end of the kite back against the wind. The elastic belly band had the effect of making the kite rise almost vertically. Sometimes it would even sail square overhead. The 8-foot kite was a very powerful one. To hold it we had to use a very strong cord, the kind used by upholsterers for tying down the springs in a chair or a sofa.
PUTTING THE KITES TO WORK.
Bill tested the strength of the kite once by hooking a spring scale to the kite string. The scale was made to register weights up to 25 pounds.
But our kite yanked the pointer immediately past the 25-pound mark as far as it would go. We judged from this that the kite would lift at least 40 pounds. Such a pull as this it seemed a pity to waste, but how to utilize the power was a problem until one day, when the kite was soaring up on a south wind, Dutchy suggested that we tie it to one of the canoes and go sailing up-stream. We tried the trick at once, but it didn't work very well, because the canoe was too light. The kite would drop unless there was a heavy pull on the string. We had better success with the scow, however, which provided a sufficient drag on the kite, and with the two kites to pull us we sailed a long ways up-stream, drifting down with the current when we had gone as far as we cared to.
THE DIAMOND BOX KITE.
[Ill.u.s.tration: Fig. 243. The Scow Towed by Kites.]
[Ill.u.s.tration: Fig. 244. Cleat for Spreader.]
[Ill.u.s.tration: Fig. 245. Corner Stick and Spreader.]
[Ill.u.s.tration: Fig. 246. The Narrow Frame.]
[Ill.u.s.tration: Fig. 247. Tacking on the Cloth.]
[Ill.u.s.tration: Fig. 248. Forked End of Long Spreader.]
Professor Keeler also gave us instructions for making a diamond-shaped box kite, and though we never built one, it may not be amiss to publish his instructions here. I quote from the chronicles of the S. S. I. E. E.
of W. C. I.:
”Materials: Four sticks, 1/4 inch thick by 5/8 inch wide by 44 inches long, for the corner sticks. Two sticks, 1/4 inch thick by 5/8 inch wide by 15 inches long, for the short spreaders. Two sticks, 1/2 inch square by about 38 inches long, for the long spreaders. Two strips of cloth 81 inches long, hemmed at each edge to a width of 13 inches. Whittle out twelve cleats to the form shown in Fig. 244. At the ends of the 15-inch spreaders nail cleats on each side with long wire brads, so as to form forks, as shown in Fig. 245, in which two of the corner sticks are held.
The short spreaders are fastened to the corner sticks, 7 inches from the ends, with brads driven through the cleats, making the frame (as in Fig.
246). To prevent the frame from skewing off sidewise it should be braced with wire running diagonally across from one corner stick to the other.
Ordinary soft stovepipe wire will do. Care must be taken to have the spreaders meet the corner sticks squarely or at right angles. Now take one of the cloth strips and sew its ends together to form a band. The end should be lapped about an inch and fastened with the sailor st.i.tch (see Fig. 223). The same should be done to the other cross strip, and then each band should be marked off with pencil lines at four points, all equidistant from each other. The two bands may now be tacked to the two ends of the frame with opposite pencil lines over the edges of the corner sticks, as in Fig. 247. The two remaining corner sticks are then nailed to the bands at the two other pencil lines. These corner sticks will now be braced apart by the long spreaders, which are notched to the right length to stretch the cloth taut. A cleat is nailed over each notch, as shown in Fig. 248, forming forks to hold the corner pieces.
The long spreaders are now forced down until they meet the short spreaders, to which they are tied with waxed string. The long spreaders may be nailed to the corner sticks by driving brads right through the cloth into the cleats and the sticks. The belly band may be fastened to any one of the corner sticks at the spreaders, and from the points where it is tied it should measure about 45 inches in length. The point where the main string should be attached to the belly band may be best determined by experiment.”
[Ill.u.s.tration: Fig. 249. The Diamond Box Kite.]
CHAPTER XXI.
THE WATER WHEEL.
Summer found us again on Willow Clump Island with heads full of new ideas. Bill had come across an old copy of Ewbanks' ”Hydraulics” in the school library. It was a book describing machines of the ancients--princ.i.p.ally devices for raising water. Rather dry reading, I thought, even though it was a wet subject; but Bill seemed to find it absorbingly interesting. I came in late one afternoon, after a glorious game of baseball, only to find Bill poring over the yellowed leaves of the ”Hydraulics” as fascinated as most fellows would be over a detective story. It exasperated me to note that he thought more of this old book than he did of our baseball team.
”Bill,” I exclaimed, ”what's got into you? I can't for the life of me see what is so entertaining in that prehistoric book.”
”Oh, go way. Don't bother me,” was the surly reply.