The spacemen redoubled their efforts, bounding along the narrow path. Onward, desperately, the sound of their heavy breathing filling their helmets. At length they reached a low rise of ground commanding a view of the trail ahead. Very faintly a despairing cry echoed in their earphones.
A hundred or so yards before them, a vague form in the gloom, stood Miller. His head twisted crazily from side to side, his body writhed frantically, as if seeking to break some invisible grip. Several times he leaped upward like some grotesque jumping-jack, only to settle down in the exact same spot as before. It was as though the trapped man were confined in an invisible cylinder which permitted him to move only in the vertical plane!
"Look!" Grant muttered. "So it's true! That's what happened to Kennerly until his heating unit gave out! And Allers, too, I suppose!" He raced down the slope toward Miller, heat-gun in hand.
As they neared the trapped man, he gave a cry of warning. "Stay back! You'll get caught!" His voice rose despairingly. "No ... no way to get free! Hands and feet stuck! Better to shoot me, now, than let me stay here till my heat-unit gives out!"
Helplessly they stared at the doomed man. To approach him meant they, too, might be trapped. But to stand there, useless, while his heating unit gave out, bringing death, as it had brought death to Kennerly! And what power known to man would permit a living being to move only in the vertical plane but not the horizontal? All at once Grant recalled the hole in the trail at the spot where he had found Kennerly. Dropping to his knees, he began very cautiously to circle Miller. All at once he found it, a copper wire concealed beneath dirt, pebbles. One jerk of his gloved fingers snapped the wire. A sudden cry broke from the trapped man. Weakly, uncertainly, he stepped forward.
"Free!" Miller cried. "I ... I can move my feet and hands any way I want, now! Thank God! The thought of staying there until I froze to death...!" He shuddered.
Grant was following the wire to where Miller had stood, was digging away a covering of earth. All at once he gave an exclamation of wonder. In the wan starlight a tangle of wires, wrapped about iron cores, lay exposed!
"Looks like a magnet!" A burly space-hand grunted, shaking a dazed head. "But there's no iron on our suits! And no magnet permits you to move only one way!"
"I don't know." Grant frowned. "But whatever this force is, it's got a clever, devilish mind behind it! This is the same kind of thing that trapped Kennerly, only we didn't reach him in time. When I first spotted Kennerly crouching in the trail, I didn't know who he was. Fired a warning shot at his feet. That must have fused the wires of the apparatus! And so I was able to approach Kennerly's body without being trapped myself! While I was taking his body back to the ship, the killer must have dug up the wrecked mechanism, planted this magnet further down the trail! If Harris hadn't been lagging a considerable distance behind Miller, they both would have been caught!"
"Sounds logical," one of the men nodded. "But why all these traps? And who's setting them?"