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This gun is only one of the hundreds that England is carrying to the battlefields to replace those captured or destroyed.

COPYRIGHT UNDERWOOD & UNDERWOOD

NO FAVORITES RECOGNIZED

This horse is swung on deck in the same unceremonious way that artillery and supplies are handled.

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Although they are now engaged in the serious business of war, these French soldiers are giving a recruit the customary

"peace-time initiation".

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The combination of spray, winter, and snow has converted this vessel into what seems to be a block of ice

supporting guns.

MAKING THE OCEAN

WARN OF ITS PERILS

By Chester Carton

FTER baffling the inventors of two continents for more than a generation, the problem of submarine signaling has

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been solved by American genius. Beginning where the others left off, Professor Reginald A. Fessenden, a former chief chemist of the Edison laboratories, has produced an apparatus which promises to become the most important aid to navigation since the invention of the compass. So important, indeed, are Professor Fessenden's achievements regarded, that the Government has co-operated with him by lending freely the use of revenue cutters, submarines, and battleships for his experiments.

Professor Fessenden's device sends messages in the Morse code thirty-one miles through the depths of the ocean, sends and receives signals at a distance of one hundred and twelve miles, enables one to carry on telephone conversations beneath the waves for a distance of half a mile, and has been used to direct submarines, submerged to a depth of a hundred feet, through a complicated series of maneuvers. The same apparatus has announced the proximity of icebergs, their direction and distance from the ship, and it has been used instead of the lead line for sounding. Finally, Commander F. A. Sawyer, of the United States Navy, has produced an adaptation of Fessenden's apparatus which will abolish the greatest peril of the sea remaining unconquered the peril from fog.

Every boy who has held his head. under water, while a chum on the far

ther side of the "swimmin' hole" struck two stones together beneath the surface, knows to what a remarkable degree water conveys sound. Nearly a century ago scientific experimenters. heard the sound of a submerged bell across Lake Geneva, Switzerland—a distance of twenty miles—and measured the speed at which the sound traveled, finding the rate to be about forty-seven hundred feet a second, as compared with about eleven hundred feet a second for air. While the atmosphere is erratic and unreliable as a medium for the transmission of sound, water is absolutely steady and trustworthy when used for the same purpose, and carries impulses four times more rapidly than air. Eddies, air currents, fog banks, and other similar factors may distort or divert sounds in air, so that it is impossible for one to tell with certainty from what direction they come; and under certain circumstances, especially in fogs, there may even be "zones of silence" in the air, in which sounds that, under normal conditions should be clear and distinct, cannot be heard at all, though they may be audible at greater distances. But a given volume of sound beneath the surface of water can be depended upon to travel in a straight line for a uniform distance, and inventors, knowing this, have always hoped to make use of this property.

The great difficulty encountered has been due to the fact that water is so much denser than air that it seemed impossible to find a way to produce a sound that would carry a useful distance. In fact, for many years, no one

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