At the present time kites are used to obtain information about the temperature and humidity of the air above us, and efforts are being made to construct a flying machine capable of carrying one or more persons.

At first sight it might appear as though there were no relation between these two matters, but they are, in reality, very closely connected. The kite is held by a string or wire, and the wind passing over the kite supports it and at the same time causes it to exert an upward pull upon the wire. To fly a kite in the ordinary way the first requisite is sufficient wind, but if the lower end of the string to which the kite is attached can be moved forward with sufficient rapidity, by fastening it, for example, to a fast steamer or motor car, the kite can be flown when there is no wind.