Yet for just a second he hesitated. He could not guess what it was that chilled his hand; that restrained for a moment his desire for the magical substance. Was it some voice of hidden warning? He could not say. He only knew that he laughed silently at himself; then, with reviving eagerness, shot his hand into the pale-blue dust. The substance was downy soft to the touch, yet was cold as stone, and caused a tingling, faintly stinging sensation to creep along his skin. Hungrily his fingers closed over it; then, with a good handful in their clutch, began to withdraw. But, as they did so, Gates was startled by a sudden grating noise, followed by a sharp click. And a violent pain shot through his wrist. Teeth of steel dug into his flesh; and, in horrible realization, he knew that he was caught! [Illustration: The sharp jaws of the thing closed on Gates' hand.] Yes, caught like a wild beast snared in a wolf-trap! It is hard to say whether, in that first stunned instant, his pain or his alarm was the greater. Yet his mind at once took in the full dread import. The pouch was but a ruse; it was equipped with hidden jaws, which would close at the faintest touch, seizing the unwary intruder. Oh, why had he not had the brains to beware? From the first, he saw that escape would be impossible. Those cruel jaws were so made that the more he struggled, the more tightly his arm would be wedged between them, and the more intense his agony--if he were not careful, his other wrist would be caught too! Knowing that he would be fettered here until his masters revived from their intoxication; and knowing also the terrible tempers of the tribe, he concluded that he would be better off dead. It was as this thought bored at his brain that he heard a sound to his left. Low, stealthy, secretive, it yet had a vaguely familiar whirr. "Earthling, listen to me!" His heart gave a convulsive leap. He felt that his last moment had come. So he had not been alone after all, had not been unguarded! One of his captors, garbed in invisibility, had been watching him, following his every movement, gloating in his helplessness as a cat gloats in the sufferings of a mouse! "Earthling, listen to me!" The words had been repeated, in the same stealthy manner. "For God's sake, who are you?" the prisoner found courage to gasp. "Soon I shall say. First, let me free you from your misery." * * * * * There came a snapping sound; the steel jaws clattered apart; and Gates, to his astonishment, withdrew a bruised and bleeding wrist. "The lower animals should not meddle with tools they do not understand!" mumbled the unseen. "By my home-world's outer ring! you did not pull down the safety clasp before sticking in your hand!" "But who--who in blazes are you?" repeated the captive, becoming bolder, although he could not believe that he had been freed for any good purpose.