"Mr. Atkins," said Baker. "Yes, Dr. Baker," said Sam Atkins. "If you hear me, wave your hands. I will observe you through the field glasses." "The field glasses won't be necessary." Both the image before them, and the distant figure on the knoll were seen to wave arms and gyrate simultaneously. For good measure, Sam Atkins turned a cartwheel. Baker seemed to have partly recovered. "There seems to be a very remarkable effect present here," he said cautiously. "Dr. Baker," Jim Ellerbee spoke earnestly, "I know you're skeptical. You don't think the crystals do what I say they do. Even though you see it with your own eyes you doubt that it is happening. I will do anything possible to test this device to your satisfaction. Name the test that will dispel your doubts and we will perform it!" "It's not entirely a question of demonstration, Mr. Ellerbee," said Baker. "There are the theoretical considerations as well. The mathematics you have submitted in support of your claim are not, to put it mildly, sound." "I know. Sam keeps telling me that. He says we need an entirely new math to handle it. Maybe we'll get around to that. But the important thing is that we've got a working device." "Your mathematical basis _must_ be sound!" Baker's fervor returned. Fenwick felt a sudden surge of pity for the director. The demonstration was repeated a dozen times more. Fenwick went over on Sam Atkins' hill. He and Baker conversed privately. [Illustration: ... _"Presence," with the crystals, was not a physical thing_ ...] "Do you see it yet?" Fenwick asked. "No, I'm afraid I don't!" Baker was snappish. "This is one of the most devilish things I've ever come across!" "You don't think it's working the way Jim and Sam say it is?" "Of course not. The thing is utterly impossible! I am convinced a hypnotic condition is involved, but I must admit I don't see how." "You may figure it out when you go through Ellerbee's lab." * * * * * Baker was obviously shaken. He spoke in subdued tones as Ellerbee started the tour of the crystal lab again. Baker's eyes took in everything. As the tour progressed he seemed to devour each new item with frenzied intensity. He inspected the crystals through a microscope. He checked the measurements of the thickness of the growing crystal layers. The rain began while they were in the crystal lab. It beat furiously on the roof of the laboratory building, but Baker seemed scarcely aware that it was taking place. His eyes sought out every minute feature of the building. Fenwick was sure he was finding nothing to confirm his belief that the communicator crystals were a hoax. Fenwick hadn't realized it before, but he recognized now that it would be a terrific blow to Baker if he couldn't prove the existence of a hoax.