Presently comes a dull explosion. The destroyer arriving over the spot where the undersea boat was last seen, has dropped a depth-bomb, which has exploded under the surface at a predetermined depth. The submarine commander grins. The bomb was too far away to do damage, although the craft has trembled under the shock. There comes another shock, this time not so palpable. Eventually all is quiet. For an hour the submarine proceeds blindly under water, and then cautiously her periscope is thrust above the surface. Nothing in sight. Orders sound through the vessel and she rises to the surface. She could have remained below, running under full headway, for six hours before coming to the surface. So the day goes on. Toward nightfall smoke again is seen on the horizon. It proves to be a large freighter ladened, apparently, with cattle. Two destroyers are frisking about her, crossing her bow, cutting around her stern. The steamship herself is zigzagging, rendering accurate calculations as to her course uncertain. By this time, of course, the submarine has submerged. The watch-officer and the commander stand by the periscope, watching the approaching craft. The periscope may not be left up too long; the watchers on the destroyers and on the deck of the vessel, which is armed, are likely to spy it at any time. So the periscope is alternately run down and run up. The submarine has moved so that the steamship will pass her so as to present a broadside. Up comes the periscope for one last look. The observer sees a puff of smoke from the deck of a destroyer and a quick splash of water obscures the view momentarily. "They have seen us and are firing." But the steamship is now within a mile, within fairly accurate torpedo range. An order rolls into the torpedo-room and the crew prepare for firing. In the meantime a shower of shells explode about the periscope. There comes a sudden vagueness on the glass into which the observer has been gazing. "The periscope has been hit." Thoughts of launching the torpedo vanish. Safety first is now the dominant emotion. Additional water flows into the tanks and the craft begins to settle. But as she does so there is a sudden flood of water into the control-room; a hoarse cry goes up from the crew. The officers draw their revolvers. Evidently the injured periscope has caused a leak. Before anything can be done there is a tremendous grinding, rending explosion; the thin steel walls contract under the force of the released energy. Above them the destroyer crew gazing eagerly at the geyser-like volume of water arising from the sea descry pieces of metal, dark objects of all sorts. The sea quiets and up from the depths arise clouds of oil, spreading slowly over the waves. The U-47-1/2 has joined many a nobler craft upon the wastes of subaqueous depths.