Page:Popular Science Monthly Volume 53.djvu/68

56 so far as 1 have learned, is in the wireless telegraph system of Signor Marconi, in which the collectors at the poles are kites of thin copper, these being connected by small copper wires to either the receiver or the transmitter, on the ground. Though Marconi claimed to have sent readable signals twelve miles. Superintendent Preece, of the English Government Telegraph System, in endeavoring to duplicate these successes, was unable to obtain a satisfactory result at a greater distance than two or three miles.

The experiments at Blue Hill have shown a difference in electrical conditions at different heights, and in different conditions of the atmosphere in respect to temperature, humidity, and movement; and there seem good reasons for confidence that ultimately this element will yield valuable results in more than one direction.

It is not improbable that if metallic kites could be sent up to the verge of some higher stratum of the atmosphere, where the contact of the diversely moving strata sometimes evolves noticeable auroras, some considerable electric charge might be obtained for telegraphic or telephonic transmission, and, possibly, by storage, for light and power.

In considering the various phenomena of kite-flying, however, we must not neglect the kites themselves. The effort of the scientists has from the first been to find a form which would give readiness of ascent, steadiness in flight, lifting power, and capacity of reaching great altitudes, together, of course, with mechanical stability and endurance under all conditions. Because of their necessary slenderness, and their delicacy of adjustment for balance and pull, all flat kites have been found precarious; consequently, not meeting