ship that did not sink very soon after being torpedoed, and that, in nearly every case, it discovered, after emerging, that it had been dealing with a real merchantman. Already this same submarine had wasted hours and immense stores of ammunition on vessels that were not mystery ships, but harmless tramps, and all these false alarms had made it impatient and careless. In most cases, therefore, the crew had only to bide its time. The captain knew that his hidden enemy would finally rise.
"Stand by!"
This command would come softly through the speaking tubes to the men at the guns. The captain on the bridge had noticed the preliminary disturbance on the water that preceded the emergence of the submarine. In a few seconds the whole boat would be floating on top, and the officers and crews would climb out on the deck, eager for booty. And this within a hundred yards of four or five guns!
"Let go!"
This command came at the top of the voice, for concealment was now no longer necessary. In a twinkling up went the battle flag, bulwarks fell down, lifeboats on decks collapsed, revealing guns, sides dropped from deckhouses, hen-coops, and other innocent-looking structures. The apparently sinking merchantman became a volcano of smoke and fire; scores of shells dropped upon the submarine, punching holes in her frail hull, hurling German sailors high into the air, sometimes decapitating them or blowing oft their arms or legs. The whole horrible scene lasted only a few seconds before the helpless vessel would take its final plunge to the depths, leaving perhaps two or three survivors, a mass of oil and wood, and still more ghastly wreckage, to mark the spot where another German submarine had paid the penalty of its crimes.
IV
It was entirely characteristic of this strange war that the greatest exploit of any of the mystery ships was in one sense a failure that is, it did not succeed in destroying the submarine which attacked it.
