"Yes," replied Sir Humphrey, "and keep our weapons out of sight as if we had come upon a peaceful errand." "I'm afraid they won't understand us, sir," said the captain gruffly; "but we'll try." The current was running very gently now, so that the approach of the boats to the promontory took time; but at last it was rounded, revealing to the occupants of the boats a scene as startling as it was strange. There, a couple of hundred yards away, was the canoe they had followed, while at various distances farther on no less than six more small canoes were dotted about, their feather-crowned crews all busily employed fishing, while as the boats glided round the tree-covered rocks the nearest Indians struck up a soft minor-keyed chant which was taken up by the crews of the other canoes, the whole combining in a sweet low melody which floated over the smoothly-flowing river, fully explaining the sounds heard from the cavern-mouth overnight. In all probability it was a fisher's song which the people imagined had some effect upon the fish they were trying to lure to their nets. Strangely wild and mournful, it rose and fell, and gained at times in force as it seemed to echo from the right side of the canon, which here rose up like some gigantic wall hundreds of feet in height, barred with what appeared to be terraces, and honeycombed with open doors and windows, row above row, from the lowest, upon which in two places smouldered the remains of fires, right up to the sky-line, which, roughly regular, was carved into something resembling the crenellations of a gigantic castle, extending apparently hundreds upon hundreds of yards. Brace had hardly swept the face of the strangely-worked range of cliff when the softly mournful chorus ceased, and as if moved by one impulse, on catching sight of the approaching boats, the Indians burst forth into a shrill piercing yell which echoed and re-echoed discordantly from the face of the rocks. The next moment every man had seized his paddle, and they were making the river foam and sparkle with the vigour of their strokes. There was no mistaking the effect produced on the Indians by the appearance of the boats: it was the feeling of horror and dread, every man plunging his paddle deeply into the water and striving his utmost to force the canoes to their greatest speed, so that they might escape from the strange beings. In all probability they were seeing white men for the first time in their lives. "What does that mean?" said Brace: "going to fetch help?" "No," said Lynton; "because this must be where they live." "Yes; there are their fires on the banks," added the captain. "But they are mere savages," said Sir Humphrey, who ceased to watch the retreating Indians, to sweep the front of the towering cliffs with his glass. "This palace must have been the work of a more highly civilised race." "And is it your opinion that they are at home, waiting to shoot?" asked Briscoe, stooping to pick up his gun.