But Leeger had disappeared from view. Back of us now was the wilderness of scales, their curved surface glistening and alive with color as the endless crawling spine followed us out of the distant blue haze. Miles of Kao-Wagwattl, and nothing showing on the surface. We were down, now, almost out of sight, yet peering over. Suddenly the form of Leeger bobbed up again, only a few feet from us. "Go back!" Leeger cried, flinging a hand at us. "Go back! He's coming!" It all happened in less time than it can be told. Leeger rose up to warn us. We saw the knife fly through the air at him. He fell with the blade through his throat. On the instant we saw the dark muscular form of Gravgak rearing up among the scales. The green-and-black diamond-shaped markings on his arms and legs glinted in the light. He had hurled his knife true. Triumph shone in his murderous eyes. He had killed the man who had stalked him to protect Vauna and Tomboldo. And now he must have believed that one of his prizes was within easy reach. His arm flashed upward. It held one of those rockstrung clubs that the savages used so skillfully. The weighted club whizzed through the air. I swung Vauna off her feet. I'll swear the rolling movement of Kao-Wagwattl helped me or I wouldn't have succeeded. We tumbled into the crevice. Then I scrambled upward. Another glimpse of Gravgak. He dived down among the crevices, moving in our direction. A moment of darkness. The scale-tops closed out the light. When they opened, he was there, coming at us. I locked with him. We fought. The movement of the surfaces gave us an upward thrust. I kicked and tumbled to the surface. He caught my wrist, but the upthrust of the Kao favored me and I jerked him upward, onto the top of the scales. We fought in the open. The rubbery footing was deadly, but it played no favorites. I struck a heavy blow that made the green-and-black lined arms shudder. Gravgak's eyes flashed as he plunged back at me. I struck him again, with the full force of my body. He bounced and tumbled. He rolled out of sight. But not for long. It was an intentional trick. He disappeared in the crevice where Leeger had fallen. When he came up, the bloody knife was in his hand. I heard Vauna's warning cry. I leaped down into the crevice. She was trying to get my coat. She knew there were explosives in it, if she could only get them into my hands. No time for that. Gravgak leaped down at me. The knife was rigid from his hand, coming down with a plunge. I kicked back, floundering against the tricky walls of the scales, and Gravgak fell down deep where I had been. I saw it happen. A sight I never expect to see repeated.