[Illustration: FIG. 15.] Many kites need attachment of bridle in but two places, while others require three, some four, and some are benefited by the use of many strings to the bridle, but the last may be used for strengthening the framework of the kite more than for general poise. The Chinese say there should never be more than three strings to the bridle, while the Japanese use many. The tailless kite may have the bridle attached at the bottom and top of the spine (the vertical stick of the frame) or the bottom and at the crossing of bow and spine. In either case the bridle must be long enough so that when it is drawn over to the side of the kite, the loop will just reach the outer points of the bow, Fig. 13; _ac_ should be the same length as _ab_, and _cd_ the same length as _bd_. The normal point of attachment of kite line is at _c_, the point that just reaches _b_ or _e_ when drawn to the side. Some bird kites have a similar bridle but much shorter between attachments. More of the form kites have three and four strings to the bridle. The three string bridle is usually two strings above and a longer one below, Fig. 14. The four string bridle has two short uppers and two long lowers, Fig. 15. For the poly string bridle, see Fig. 16. Some have advocated an elastic bridle but the writer has never found it of any great advantage. [Illustration: FIG. 16.] [Illustration: FIG. 17.] A double bridle with a kite line to each, makes a dirigible kite possible, which may be useful in a number of ways and which can give much amusement in kite antics that is not possible with a single kite line. A double bridle is illustrated in Fig. 17. Such a kite can be driven at will. The kite becomes a sail and can be pulled to right and left, in circles and various contortions, out of the ordinary. =Kite Lines.= A three or four ply cotton wrapping string is used more than any other and is very satisfactory for three-foot kites and smaller. The hard twisted cotton seine twine comes from six to over a hundred ply, and is excellent for kite lines. It is strong and does not burn the hands, nor kink as much as hemp twine. For high flying or racing work, a light strong cord is necessary. A small kite can carry up a great amount of silk or linen thread but one should have a reel and gloves to handle it. Shoemakers thread and upholstering twine are also used. Some think that waxing a string makes it stronger, but by actual tests before and after waxing, there was no appreciable difference in the amount of endurance of strain before breaking. Waxing does preserve the string and prevents fraying and untwisting. When kites are put up in tandem, the string need only be as strong for the first kite as is ordinarily used for one of its size, but as other kites are added the size of the cord must be increased. This grading of the string, greatly reduces the total weight and cost of the kite line.