KITE flying dates back to very ancient history. The Chinese, both children and grown people, have been flying kites for ages. In this amusement the people of China and Japan are unquestionably far ahead of us in many respects, but judging by the progress made in two years by the boys of Los Angeles, California, it may be safely predicted, that in a short time we may expect to see some wonderful aerial crafts of Yankee invention that will far excel the Oriental.

Kite making and kite flying has received a great impetus the last few years as the result of the efforts of some of the boys who have "older grown." Men of science have found some very practical uses for the frail structures of the air. These men have not only performed certain experiments by means of kites, but have developed considerable aerial craftsmanship. All these developments have been of decided advantage to the small boy, for boys keep their eyes open and are apt scholars when interesting possibilities come their way; so they are no longer limited to the English bow-kite with its long suspended tail; they have turned kite-surgeon, and amputated this appendage.

The kites of to-day are more scientific and more difficult of construction as well, but when a boy sees they are possible to construct, and that other boys have constructed them, he is tempted to try. "What another boy has done, I can do." It is an old saying, and one not sufficiently used, "It is good to put temptation to work in the boy's way." In kite making the boy has an incentive to do some good, hard, original thinking in working out plans already prepared, and as he works on these, new suggestions, vague perhaps at first, pass before his mental vision, which he pursues, sometimes to failure, but very often to successful construction and operation.

All boys who have had some experience in kite flying probably know that

It takes the wind to make the kite go; Just how, they don't quite know.

Without going too deeply into the physics of the various problems of kite construction, the consideration of a few of the simpler ones may not be out of place. If a boy undertakes to fly a tightly stretched, plain-surface kite, he will soon find he has about as foxy a problem as he wants to tackle. He will soon discover that he needs ballast, but the ballast needed is not mere weight. A piece of lead suspended to a string will not answer the purpose - will not give poise to a darting kite. It finds its vertical position too quickly. If we had a very steady breeze, we might work out the right attachment of bridle, and add just the right ballast here and there to make a partial success, but we must consider cross-currents, whirls and calms, and all such disturbances that a boy encounters in all kite-flying. The boys use a tissue paper tail for ballast. The tail steadies the kite, not so much by its actual weight, as by the pull due to the resistance it offers in being drawn through the air. It takes much longer for a tail of this kind to drop to its normal position and is a constant balancer during that time, being sufficient to carry the kite through a temporary disturbance, or to the adjustment of a contrary breeze. It is the same principle as the one employed by the rope walkers who poise themselves by the use of fans. So much for kites with tails.

The tailless kite must have some recompense for the loss of its tail, and this is to be found in its construction. Instead of the tight-covered surface, the cover is put on loosely, Fig. A. The cross piece of the frame is bowed, and this throws the vertical stick, called the spine, well forward. The projection of the spine to the front, forms a ridge on the front surface, like the keel of a bird, and may be likened to the keel of a canoe, also. The first canoes were hollowed out of logs and were round on the bottom. Such a one would soon leave the uninitiated on the wrong side - the under side - but later there was a keel extending down deep into the water which gave greater poise. Just so with the kite. The boat is not square to the front or to the rear, so the tailless, the best of all flyers, tapers at the top and bottom. The keel is sometimes projected straight out from a flat surface, Fig. B. Kites with keels will ride a rather turbulent atmosphere, and very soon recover their equilibrium. Box kites have vertical or oblique surfaces that keep the kite in poise without the assistance of tail or special keel.

What makes the kite rise? The same thing that causes the windmill to turn; and this is true with a box kite, as well a plain one. The windmill fan turns at an angle to the breeze, and the surface of the kite does the same. Fig. C will help to demonstrate this principle. The air in moving against the kite, has a tendency to push the obstacle out of the way, and would carry it on away with it but for the fact that there is usually a boy attached to the other end of the anchor line. The air must then get by some way, as there is other air pushing from behind. The attachment of the bridle is such as to throw the upper part far forward and so cause most of the air to escape by the under route, as shown by the congestion of arrows, Fig. C. But the thickening of the arrows has a double meaning: it means compression, and compression means resistance; but that resistance is nearly all on the under side of the kite and is just so much more of a lifting force. The force of gravity has all the while to be overcome, but in addition to the lifting power, if the kite is not well balanced, the air will pass too much to one side or the other, and if the bridle should not be well adujsted the kite will dodge and dive and cut up antics sufficient to try the most patient. One boy tried to make a "Foxy Grandpa" kite, but he said the grandpa proved so foxy that he would stand on his head. It lacked poise somewhere.

The Construction And Flying Of Kites 5