But in respect to practical usefulness, of aerial transportation of as a means persons of goods, the flying flivver gives no promise of living up to the flivver reputation, in the opinion of aviation experts. The Dewoiline machine is different from a motorless glider chiefly in that it has a motor, the radiation of the engine, the wing surfaces and skeletons and the body had to be constructed more strongly than in the case of a glider. This meant additional weight, and, together with the weight of the motor itself—said to be only forty pounds—made the whole craft considerably heavier than a glider. The total "tonnage" of the flivver was about 400 pounds, without the pilot, which is double the aviéight of man-carrying gliders. The average man-carrying gliders have been made weighing even less than the average of 200 pounds. The Dewoiline craft is different from a regular airplane, mainly in that the motor is of much lower horsepower and the whole machine is smaller. The motor mounted in lighter and lighter, the flying flivver is a two-cylinder Clerguet of twelve horsepower. Ordinary small airplanes carry 100 horsepower motors, on the average; though improvements in propeller construction and wing design are gradually lowering the horsepower requisite in proportion to the weight of machines. The Sperry fast messenger plane, recently tested over Long Island, has a 60-horsepower engine. Of the smallest in the country,  This plane is one of the most powerful in the world. In point of size, the Dewonine invention measures 40 feet from wing tip to tip and 15 feet over all in length. 