And then abruptly something clicked in his brain like a puzzle piece fitting into a slot. This chamber housed the mechanism that made the rejuvenation salts adaptable to the Kamalis. The secret was vibration, a bombardment of supersonic waves, causing a basic mutation of the crystals' molecular structure.
The Hudrites were the Venus equivalent of the Earth cricket. But where a cricket gave off vibrations of 8,000 a second, the frequency of a Hudrite had never been measured. It was said to be more than two million cycles.
The vibrations from these insects were picked up by the parabolic horn and a sensitive detector and stepped up by a cyclestat. When the sound waves struck the crystals, they responded to it at their frequency and by its vibrations gave rise to a varying voltage. The sound waves of the Hudrites were thereby converted into electrical vibrations and these electrical waves amplified with the aid of vacuum tubes.
The two were then united, and this bombardment of supersonic and electrical waves changed the structure of the Deleon crystals. No doubt the Kamali Oligarchs had discovered through long experiment just how long a vibration exposure was necessary to make the salts potent and still not effect their mental powers. The process undoubtedly took months of Venus time.
But the space-rats, Halleck and Gately, had no intention of waiting that long. They planned to expose the crystals for the shortest possible time and then sell them to unsuspecting citizens of Earth.
Another thought struck Simms. Sterns! What had killed him?
He had the answer an instant later. Up on the wall a warning bell sounded and a red light flashed off and on. From a microtone speaker sounded that same deep-toned drone. Again it began to mount swiftly up the octaves, rising steadily to a high-pitched shriek preparing the way for the supersonic vibrations of the Hudrites. The lieutenant clapped his hands to his ears, fell to the floor in writhing agony.
Stabbing lancets of pain darted through his brain. He felt his eyes protruding; his head seemed ready to explode. With a mighty effort he managed to jerk on his dehydration mask, slide the protective ear-caps into place. Even then the sensation was only partly relieved, and he stood, heart pounding, waiting for the mad vibration to stop.
When at length it came to an end, a glance at the Deleon Salts showed him they had colored from a light yellow to a deep orange. Tiny facets of irridescent flame now played over their surfaces.