and thus, in a way, confirmed their calculations. One of the subchasers promptly ran ahead and began to drop depth
charges on this wake. There was not the slightest doubt that the surface boat was now directly on top of the submarine. After one of the depth charges was dropped, a black cylindrical object, about thirty inches long, suddenly rose from the depths and jumped sixty feet into the air; just what this unexpected visitant was no one seems to know, but that it came from the hunted submarine was clear.
Under such distressing conditions the U-boat had only a single chance of saving itself; when the water was sufficiently shallow—not deeper than three hundred feet—it could safely sink to the bottom and "play dead," hoping that the chasers, with their accursed listening devices, would tire of the vigil and return to port. A submarine, if in very good condition, could remain silently on the bottom for two or three days. The listeners on the chaser tubes presently heard sounds which suggested that their enemy was perhaps resorting to this manoeuvre. But there were other noises which indicated that possibly this sinking to the bottom was not voluntary. The listeners clearly heard a scraping and a straining as though the boat was making terrific attempts to rise. There was a lumbering noise, such as might be made by a heavy object trying to drag its hulk along the muddy bottom; this was followed by silence, showing that the wounded vessel could advance only a few yards. A terrible tragedy was clearly beginning down there in the slime of the ocean floor; a boat, with twenty -five or thirty human beings on board, was hopelessly caught, with nothing in sight except the most lingering death. The listeners on the chasers could follow events almost as clearly as though the inside of the U-boat could be seen; for every motion the vessel made, every effort that the crew put forth to rescue itself from this living hell, was registered on the delicate wires which reached the ears of the men on the surface.
Suddenly sharp metallic sounds came up on the wires. They were clearly made by hammers beating on the steel body of the U-boat.
"They are trying to make repairs," the listeners reported.
If our subchasers had had any more depth charges,
