"Trouble?" Hanlon asked naively. "Was I supposed to have some?" Then he couldn't help grinning. "Thanks for the info," and went to his room, took a shower to cool off after that muggy heat in the mine, then tumbled onto his bunk for a nap until dinner-time.

Those first days so thoroughly disgusted George Hanlon as he saw the continued and senseless brutality the guards used toward their native "slaves," that he had trouble concealing his feelings. He continued to treat his Greenies with the respect he felt was due them, and he could not help but notice they seemed to look on him more and more as their friend. They always smiled when he looked at them, and before many days he discovered that his crew was doing more work than any of the others. His mind-probing had convinced him they were high enough in the scale of evolution to know the meaning of gratitude, and he could tell they were repaying his kindness with co-operation.

He had begun to make much more sense out of the pictures he saw in their minds, and to get some glimmerings of understanding about their alien concepts. Also, it was increasingly borne in upon him that they did "talk" to each other, and he guessed shrewdly that the reason no one could hear them was because their voices were above ... or below? ... the range of human hearing. "Above," he finally deduced.

That gave him the idea for an experiment, and he started whistling as loud as he could, gradually raising his tones until he was at the top of his range. He saw with interest and excitement that the last one or two shrillest notes seemed to attract their attention. Their silly-looking little triangular ears perked up and began twitching. They turned about, as though seeking the source of that sound, while every mouth began working with signs of utmost excitement, and his mind caught concepts of surprise and wonder.

That convinced him and so, in his next several off-hours, he surreptitiously collected various articles and pieces of material, and in his room started the construction of a little machine. His course in the Corps school had included considerable mechanics and electronics, and the tearing down and rebuilding of many of the machines and instruments the Corps used.

What he was trying to make now was a "frequency-transformer." If it would do what he was sure it would, and if he was right about the Algonians having vocal ability, they should be able to hear each other, and some day he might learn their language well enough to converse with them.

He finished it and smuggled the little box-like machine into his place in the mine. When he had his crew down there and working at their tasks, he got out the little box. He turned on the current from the small battery installed in it, then began talking at the same time he was turning a rheostat higher and higher. Finally he noticed those mobile ears began to twitch, and as he turned the tones higher and still higher, more and more of the natives stopped work and turned toward him. Finally he noticed an intenser excitement among them, and they dropped their tools and came crowding closer to him and his machine, their little eyes almost emitting sparks of excitement.

He thrilled with the realization that it worked. Now he turned another knob more and more, and gradually from the speaker came a jumble of sounds much like "mob-mutter," but very low. He kept on turning the rheostat until the incoming voices seemed about the same pitch as his own voice.

The excitement of the natives had grown to tremendous proportions, and his own equalled theirs. Their little mouths were working faster, and an expression almost like laughter came onto their peculiar little faces, as they heard his voice and knew he could now hear theirs.

Hanlon's own smile almost cracked his face. He realized he had learned something none of the greedy, power-mad Simonideans knew, and felt that here was the possible beginning for his campaign to free these poor native slaves.