"No beach, sir, and the cliff's like the side of a ship. Looks to be deep water right into the cave's mouth." "Back to the boat, then. Bring that flag along." The descent was swift, at times reckless, but the party embarked without accident. Soon they were forging through the water at racing speed, the boat leaping to the impulsion of the sailorman's strongest motives, curiosity and the hope of saving a life. IV THE TWIN SLABS Within half an hour the gig had reached the mouth of the cave. As the coxswain had predicted, the seas ran into the lofty entrance. Elsewhere the surf fell whitely, but through the arch the waves rolled unbroken into a heavy stillness. Only as the boat hovered for a moment at the face of the cliff could the exploring party hear, far within, the hollow boom that told of breakers on a distant, subterranean beach. "Run her in easy," came the captain's order. "Keep a sharp lookout for hidden rocks." To the whispering plash of the oars they moved from sunlight into twilight, from twilight into darkness. Of a sudden the oars jerked convulsively. A great roar had broken upon the ears of the sailors; the invisible roof above them, the water heaving beneath them, the walls that hemmed them in, called, with a multiplication of resonance, upon the name of Darrow. The boat quivered with the start of its occupants. Then one or two laughed weakly as they realised that what they had heard was no supernatural voice. It was the captain hailing for the marooned man. No vocal answer came. But an indeterminable space away they could hear a low splash followed by a second and a third. Something coughed weakly in front and to the right. Trendon's hand went to his revolver. The men sat, stiffened. One of them swore, in a whisper, and the oath came back upon them, echoing the name of the Saviour in hideous sibilance. "Silence in the boat," said the captain, in such buoyant tones that the men braced themselves against the expected peril. "Light the lantern and pass it to me," came the order. "Keep below the gunwale, men." As the match spluttered: "Do you see something, a few rods to port?" asked the captain in Trendon's ear. "Pair of green lights," said Trendon. "Eyes. _Seals!_" "_Seals! Seals! Seals_!" shouted the walls, for the surgeon had suddenly released his voice. And as the mockery boomed, the green lights disappeared and there was more splashing from the distance. The crew sat up again.