"Not on my own responsibility," replied the chief officer. "Until the captain gives the order--ah, here he is." "I cannot understand how the detector is acting," said Captain Restronguet, as he gained the group of officers. "I have most carefully tested the currents and examined the platinum contact breakers. The instrument seems in order, yet it records nothing of the presence of the ’Vorwartz.’ It is inexplicable." "The ’Vorwartz’ is doubtless beyond the field of electrical action, sir," remarked Kenwyn. "So I have been told before," replied Captain Restronguet with asperity. "All the same that theory will not hold good. We ought to have had an intimation of that craft’s presence when she torpedoed the ’Noord Brabant.’ How can you explain that?" "Don’t you think, sir, we ought to submerge the ship?" asked Devoran, anxious to change the subject. "The glass is falling----" "There is plenty of time," declared the captain, who was evidently not in his usual easy-going humour. "It certainly looks threatening, but at this moment the sea is as calm as glass. Look at those sharks, Devoran. Vicious looking brutes, aren’t they? Suppose we give the men an opportunity at rifle practice." The captain strolled off to watch the antics of the tigers of the deep, for four ferocious-looking sharks had been persistently following the "Aphrodite" as if anticipating a catastrophe. The chief officer, although he would much rather have preferred to make all snug and dive to a depth of seven or eight fathoms, was not a man to quibble. He made his way to the hatch-way, to call up the small-arms party. Kenwyn stood a few paces from his superior, while Hythe, unwilling to say anything that might lead to his being snubbed, remained by the after conning-tower. Suddenly the semi-gloom was rent by a vivid flash of lightning, that played upon the metal deck and upon the placid surface of the ominous sea. A deafening peal of thunder succeeded the flash. For a moment the sub was dazzled by the glare. When he looked aft, Kenwyn was lying on the deck, a portion of the stanchions and rails were shattered, and Captain Restronguet nowhere to be seen. Raising a shout of "Man Overboard!" Hythe took a running dive and plunged into the sea. He struck the water heavily, for the "Aphrodite" was moving at a good speed. He might very well have broken his back but for the velocity with which he executed his dive. Not till he rose to the surface did he give one thought to the dreaded sharks: it was then too late to count the risk. Fortunately the monsters, frightened by the flash of lightning, had for the time being disappeared. Hythe struck out to the spot where the bubbles indicated the captain’s position, for, winded by the shock, the unfortunate man was sinking never to rise again.