Floating Mine.
Here is a little picture of what is known as a floating mine. It consists of a hollow, pear-shaped case, containing an electric battery and a large amount of gun-cotton, or some other high explosive. This mine is thrown into the sea, and by means of an iron weight is made to float three or four feet below the surface. If the mine is struck hard, it will cant over sixty-five or seventy degrees. Then the mercury in a little cup would overflow, and by so doing would complete an electric circuit and explode the gun-cotton. So terrible is the explosive force of gun-cotton, that it will tear asunder the biggest ship, and either cripple it or send it to the bottom. Never before has any nation strewn the open seas with such floating mines, and their use in this way is against all the laws of war which are observed by civilized nations.
Sweeping up mines in the North Sea.
The Germans soon discovered that large mine-layers ran a great risk of being sunk by the guns of our warships, so they employed fishing-boats and other small craft to lay these deadly engines in the sea. Many of these ships flew the flag of a neutral Power, and thus pretended that they were engaged on lawful and peaceful business. The North Sea became a death-trap, and our Admiralty had to meet the danger by employing a large number of trawlers to sweep up the mines.
The work is done in the following way. Two trawlers sailing parallel with each other drag through the sea a steel hawser which is attached to each of them. The hawser drags the mines along, and they are then picked up. You can readily understand how dangerous this work is. The trawlers themselves may strike a mine, and be blown up; or two mines drawn along by the hawser may collide when they are near to the trawlers, in which case the same result follows. Many gallant smacksmen have lost their lives in trying to free the sea from this terrible peril. We ought to think of them as heroes of the best and highest type. Always remember that it is more glorious to save life than to destroy it.
On the 6th of August a flotilla of British destroyers, accompanied by the light cruiser[176] Amphion,[177] sighted a German vessel off the Dutch coast engaged in throwing out floating mines. The Lance, a British destroyer, at once attacked this vessel, and in four shots destroyed her bridge, tore away her stern, and sank her—all within the space of six minutes. Some fifty members of the crew were saved by the British boats. Though the mine-layer was at the bottom of the sea, she had done her deadly work, and was soon to achieve a victory. As the Amphion was steaming towards Harwich, and was about thirty miles off Aldeburgh, she struck one of the mines laid by the sunken ship, and was instantly blown up. The bow of the ship was shattered, and in less than twenty minutes she sank, with a loss of 131 lives. The captain, sixteen officers, and 135 men were saved; but twenty German prisoners confined in the bow were killed by the explosion of their own mine. Since the Amphion went down, many peaceful merchant ships and trawlers, both British and neutral, have been sunk by these mines, as well as two other British warships.
Here is a section of a submarine, a type of vessel which is now being used for the first time in warfare. You see that it is shaped like a rather fat cigar, tapering towards its after or tail end. In the centre of the top of the hull we see a small conning-tower. At the stern there is a propeller, and also a series of rudders which enables it to steer to and fro, or up and down. If you study the picture, you will see what the interior of a submarine is like. By means of tanks, which can be filled with water or emptied, the submarine can sink or rise at will. When she comes near an enemy, she sinks until only a short mast appears above the surface. This mast is a hollow tube fitted with a lens and mirrors, so arranged that images of objects outside the boat and above the surface are thrown on to another mirror, where they are examined by means of a magnifying glass. This "periscope," as the hollow mast is called, is the eye of the submarine. It enables her to see when her hull is beneath the waves. If she sinks altogether, or if the periscope should be carried away, she is blind and can see nothing.