But Thorn only nodded.
"I thought of that!” he said hoarsely. “I built an automatic modulator into the thing. It will start projecting waves of frequency down in the sixteenth octave, and run up to the forty-fifth, by steps of twenty vibrations each. You know all wave-locks are keyed in those octaves, for above them you get heat radiations."
"It might work,” Sual Av agreed. “Most locks have an error-margin of ten vibrations per second, so your automatic step-ups ought to overlap all frequencies in those octaves."
Thorn was already at the door. He held the end of his little makeshift projector against the inertrum door just inside the wave-lock. He was counting on the high power of his vibrations to penetrate the inertrum from inside, and reach the lock.
The little projector hummed as he touched its switch. Invisible waves were shooting from it into the lock, changing frequency by 20-vibration jumps each fraction of a second.
In a moment came a click from the wave-lock! The bolt had drawn back, as the right frequency released the lock.
"By heaven, it worked!” Gunner Welk exclaimed hoarsely, his eyes lighting with wild hope now.
Thorn peered tautly out through the door-grating. The two SP guards on duty were standing a few yards down the corridor, evidently discussing the storm that roared above.
Gunner and Sual Av now removed the needlelike electrodes of the psychophones from the tiny incisions, at the back of their skulls. They staggered stiffly from the chairs to Thorn's side, as he gently opened the unlocked door.
One of the SP men, seeing the cell door open from the corner of his eye, yelled and reached for his atom-pistol.