Page:Popular Science Monthly Volume 64.djvu/153

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POPULAR SCIENCE MONTHLY.
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sitting in a chair suspended some yards below the machine. As the ultimate machine will probably be of tougher material than wood and silk, in time of war the operator and the motor would be protected as well as hidden, instead of being a splendid target for every shot from below.

Kites that are tetrahedral in form, as the red and white fliers shown in Figs. 6 and 9 and those used to form the superstructure of Mabel II., have perfect equilibrium, but because of their small resultant area of horizontal or sustaining surface, their lifting power, though considerable, is not as great as Dr. Bell is satisfied to obtain. His latest combinations have, therefore, been made in the hope of obtaining Fig. 20. Model of Mabel II. in Air. greater horizontal surface, and thus greater lifting power. In Figs. 21 and 22 is shown a new form of kite, Victor I., which is undoubtedly the most wonderful kite ever devised and put together.

This great H-shaped kite rose from the hand, without running, in a breeze so light that a flag on a pole fifty yards away hung limp and motionless. It glided up and up until it was flying six or seven hundred yards high, steady as a table top. The breeze at that elevation was perhaps five or six miles, though on the ground the movement of the air was so light as to be imperceptible even on the grass or trees. In a breeze of fifteen miles it flew as steadily as before, but nearer the perpendicular and with a tremendous pull.

A glance at the photographs will readily explain what makes the kite such a remarkable flier. The cells of the two wings are reversed, the keels of the cells pointing up instead of down, and the tips pointing down instead of up, while above each tier of cells stretches a wide aeroplane. This wide expanse of sustaining surface helps the winged cells tremendously and at the same time does not interfere with their working. Victor I. is three meters long, three meters wide and one meter deep and weighs only twelve pounds. The flying weight is only three hundred and fifty grams to the square meter of horizontal surface. A smaller kite of similar model has been constructed whose flying weight is about two hundred grams.