"Finding the crew of the patrol could take care of themselves in their small boats and learning that the submarine had run over to the westward, where we knew chain net traps to be laid, we circled in that direction. "Our powerful motors thrummed evenly. The water seemed to part ahead of us, and the gunners squinted along the surface, looking for the glimpse of a periscope or the first sign of the hull of the U-boat if she should be proceeding awash. CREW THRILLED WITH JOY. "Suddenly, off to the west, we made out her periscope. Intense joy thrilled our little crew. She was inshore from us. She was between our circular course and the chain nets--in the trap. The periscope we had seen might be a dummy, for a submarine frequently casts loose a phoney periscope to draw fire, but, at any rate, she must have been between us and the nets if she cut it loose. "Presently, probably after a look around, the periscope suddenly disappeared, and we knew it was a real one with a German U-boat on the end of it. Like a flock of falcons we were swooping down on the prey. "Abruptly the lead boat comes to a dead stop and lists heavily to starboard. Evidently something is wrong. We see men crawl out over the stern and fish around with boat hooks and poles. Cold as it is, one man goes overboard and remains under water so long we could not believe he would come up alive. The boat had fouled the chain nets. "Circling round in an ever smaller radius, we search the water for a periscope, a shadow, or the conventional 'streak of dirty grease' or 'line of bubbles.' "All of us have towing torpedoes out. These are bombs on long cables which are towed astern and sink to a certain specified depth. If the cable fouls anything at all, as the boat goes ahead, the bomb pulls up to it, and, when it bumps, it explodes. "We are in line. Suddenly there is a crash and a roar just ahead of us. I am thrown off my feet. Barrels of water splash down into our cockpit and roll off the decks. The bow lifts itself clean for a second. I think that the submarine has blown us up. Perhaps I am dead already. "Then we settle down again, and except for a scared look on the faces of a couple of men and rather nervous, forced jests on the lips of others, we are plowing ahead just as before. "Nothing has happened except the towing torpedo of the boat in front of us in the line fouled a submerged spar, or a bit of wreckage, and exploded right under our bow. 'If we had been a few yards closer we would never have been there any more.' FOULS A SUBMERGED SPAR. "As we realized what had happened, our tongues were loosened, and, if the crew of the boat ahead could have heard what we said about them, we would have lost their friendship most assuredly. "Way inshore, after a circling chase of perhaps twenty minutes, the submarine came up. She was in such shallow water that she probably was having trouble in operating submerged. She was gone then.