“Righto. We’ll be there. So long till then.”
When Dave arrived with the professor, he found that the stage had been set for a moving-picture show. He was glad of that; it had been months since he had seen one. He was hardly prepared, however, for the type of show it was to be.
The room was darkened. Beside him, sat the professor. There came the peculiar snap-snap of the carbons as the power came on. The next instant a dazzling light fell upon the screen, and out into that light there moved a half-score of little yellow men. Some were working industriously at a machine which cut cubes of earth from the bank before them. Others were carrying the cubes away and piling them.
Professor Todd moved uneasily. He put his hands to his eyes, as if to shut out the scene. Then unexpectedly he cried out, as if in pain:
“My head! My head! He struck me.”
“Who struck you?”
Dave looked about. There was no one near them.
“The yellow man; he struck me,” cried the professor. Then he covered his face with his hands and his body swayed back and forth with suppressed emotion.
Johnny moved silently toward them.
“It’s coming back to him. When he regains control of himself, he will know everything. It was the flash of light and the familiar scene that did it. Of course, you know that is the film he sent out to us when he was a prisoner in the mine.”