During the last three weeks of August and the first week of September ships of all sorts were sunk at the rate of about sixteen a week. Then came a rapid falling off, and during the week ending 10th October only two ships were sent to the bottom. The submarine blockade was fizzling out. The Germans had changed their policy, not because of the protests of the Americans, but because they had discovered that the game was not worth the candle. Mr. Balfour, in a letter to a correspondent, gave the true reason why the Germans were bringing the blockade to an end. He said that while the losses of German submarines had been very great, the British merchant navy was stronger than when the blockade began. Though many innocent persons, women and children as well as men, had been robbed and killed, the criminals had paid a heavy toll. The reason why the Germans had changed their policy was not because the United States had protested, not because the Germans had revolted against lawless cruelty. "No. The reason is to be found elsewhere. It is to be found in the fact that the authors of the submarine policy have had time to measure its effects, and that deeds which were merely crimes in May, in September were seen to be blunders."
By the month of June the British navy had learnt the art of capturing the submarines of the enemy; and so expert had it become in this work that a U boat, once discovered, had but little chance of escape. Submarine-hunting became the great sport of the navy, and every young officer and bluejacket was eager to engage in it. We do not know how many German submarines were destroyed, but we were informed, through America, that seventy-eight of them had been seized or sunk, and that in December 1915 at least five of the Kaiser's submarines, manned by British seamen, were doing splendid work against his ships in the Baltic. The British only rarely announced their successes, and the German submarine crews were always in doubt as to the fate of their fellows. Before long their nerve failed them, and even at the beginning of their voyages they were disheartened and hopeless.
The methods by which the enemy's submarines were captured or destroyed were not revealed, but we know that fast motor boats, each armed with a powerful gun, were employed in the hunt, and that steel nets were sometimes used. When a big fish was caught the floats of the nets gave warning, and destroyers promptly arrived to deal with it. Innocent-looking patrol boats were sometimes attacked, and, too late, the biter discovered that he was bitten. There is a story that a submarine commander, approaching one of these patrols, called out, "I give you ten minutes to take to your boats;" whereupon the skipper, whipping a concealed gun round and preparing to fire, returned answer, "And I give you three minutes to go to the bottom."