Smithy had seen Rawson pull himself to the top of the great square-edged rock. Sensing that danger of some sort was threatening, he had started to run to the aid of the struggling man. Then came Rawson's cry. "Back!" he shouted. "Get back, Smithy! I'm coming--" But he did not come; and Smithy, halted by the command, was frozen to sudden, panic-stricken immobility by that which followed. He saw the leaping things, like grotesque yellow giants. They came from the sand; then red ones leaped up from the open throat that had suddenly formed. They held flame throwers, the red ones; and the green lines of fire melted the rock from beneath Rawson's feet. All in the one second's time, it was done, and Rawson's body, his arms wide flung, was hurtling downward into the waiting throat and the threatening red glow from within. Then the carriers of the flame throwers vanished again into the pit, and there was left only a huddle of giant figures that tore at the loose sand and ash with their hands. They threw the material in a continuous stream; the air was full of cascading sand. To Smithy they were suddenly inhuman--they were almost animals; men like moles. And they and their companions had captured Dean Rawson--sent him to his death. Slowly the watching man raised himself from the crouched position that had kept him hidden. They were through with their work, these great yellow-skinned naked men--or mole-men. Six of them--Smithy counted them slowly before he took aim--and two were armed with flame-throwers. Smithy rested his arm across the little hummock of gritty ash that had sheltered him and sent six flashes of flame through the night toward the cluster of bodies. * * * * * He made no attempt to aim at each individual--the shapes were too shadowy for that. And he had no knowledge of what other weapons they might have. One thing was sure: he must take no chances on facing the red ones single-handed. He rammed his empty pistol back into its holster as he turned and ran--ran with every ounce of energy he possessed to drive his flying feet across the crater floor, out through the cleft in the rocks and down the steep mountainside. He was stunned by the suddenness of the catastrophe that had overtaken them. The horror of Dean Rawson's going; the fearful reality of those "devils from hell" that old Riley had seen--it was all too staggering, too numbing, for easy acceptance. Time was required for the truth to sink in; and through the balance of the night Smithy had plenty of time to think. He dared not go back to the camp where ripping flashes of green light told him the enemy was at work. And then, even had it been possible to creep up on them in the darkness, that one chance vanished as the desert about the camp sprang into view. One after another the buildings burst into flame, and Smithy was thankful for the concealment of the vast, empty desert. * * * * *