This time it was seen by all who stood by. The periscope was extraordinarily small, hardly larger than a stout hoe handle, and not more than two feet above the choppy sea. "Full speed ahead," said the captain. "Sound general quarters." I do not think there was a heart there that was not beating high, but outwardly things went on just as calmly as they had before the periscope had been sighted. The fans of the extra boilers began to roar. The general quarters alarm, a continuous ringing, sounded its shrill call. Men tumbled to their stations from every corner of the ship, some going to the torpedo tubes, some to the guns, others to the depth charges at the stern. The wake of the destroyer, now tearing along at full speed, resembled a mill race. And now the destroyer began a beautiful manoeuvre. She became the killer, the avenger of blood. Leaving her direct course, she turned hard over to port, and at the point where her curve cut the estimated course of the German, she tossed over a buoy to mark the spot at which the German had been seen and released a depth bomb. The iron can rolled out of its chocks, and fell with a little splash into the foaming wake. The buoy, a mere wooden platform with a bit of rag, tied to an upright stick wobbled sillily behind. For about four seconds nothing happened. Then the seas behind us gave a curious, convulsive lift, one might have thought that the ocean had drawn a spasmodic breath; over this lifted water fled a frightful glassy tremor, and an instant later there broke forth with a thundering pound a huge turbid geyser which subsided, splashing noisily into streaks and eddies of foam and purplish dust. The destroyer then dropped three more in a circle round the first--a swift cycle of thundering crashes. Meanwhile the convoy, warned by our signal and by the uproar turned tail and fled from the spot. Great streamers of heavy black smoke poured from the many funnels, revealing the search for speed. In the area we had bombed, a number of dead fish began to be seen floating in the scum. By this time some of the vessels from the escort of the convoy had rushed to our assistance, and round and round the buoy they tore, dropping charge after charge. The ocean now became literally speckled with dead whiting, and I saw something that looked like an enormous eel floating belly upwards. [Illustration: The last of a German U-boat. The depth bomb that destroyed her was dropped by the destroyer shown in a corner of the picture] The convoy disappeared in a cloud of smoke. Little by little the excitement died away. Finally the only vessel left in sight on the broad shield of the sea was another American destroyer, our partner on patrol. The 305 was fitted with listening devices, and she agreed to remain behind to keep an eye and ear open. We were to have a word from her every half hour.