"You're entirely justified, Dr. Lowry, in protesting against an apparently arbitrary act of interference with the work you've carried out so devotedly at the request of your government." One of Mr. Green's better-known characteristics was his ability to interrupt without leaving the impression of having done it. "Now, would it satisfy you to know that Colonel Weldon has been acting throughout as my personal deputy in connection with the project--and that I was aware of the conditions you mention before they were made?" * * * * * Dr. Lowry hesitated, said, "I'm afraid not. As a matter of fact, I do know Weldon well enough to take it for granted he wasn't simply being arbitrary. I...." "You feel," said Mr. Green, "that there are certain extraneous considerations involved of which you should have been told?" Lowry looked at him for a moment. "If the President of the United States," he said drily, "already has made a final decision in the matter, I shall have to accept it." The image in the phone field said, "I haven't." "Then," Lowry said, "I feel it would be desirable to let me judge personally whether any such considerations are quite as extraneous as they might appear to be to...." "To anybody who didn't himself plan the diex thought projector, supervise its construction in every detail, and carry out an extensive series of preliminary experiments with it," Mr. Green concluded for him. "Well, yes--you may be right about that, doctor. You are necessarily more aware of the instrument's final potentialities than anyone else could be at present." The image's mouth quirked in the slightest of smiles. "In any event, we want to retain your ungrudging co-operation, so Colonel Weldon is authorized herewith to tell you in as much detail as you feel is necessary what the situation is. And he will do it before any other steps are taken. Perhaps I should warn you that what you learn may not add to your peace of mind. Now, does that settle the matter to your satisfaction, Dr. Lowry?" Lowry nodded. "Yes, sir, it does. Except for one detail." "Yes, I see. Weldon, will you kindly cut yourself out of this circuit. I'll call you back in a moment." Colonel Weldon's room vanished from the phone field. Mr. Green went over to a wall safe, opened it with his back to Dr. Lowry, closed it again and turned holding up a small, brightly polished metal disk. "I should appreciate it incidentally," he remarked, "if you would find it convenient to supply me with several more of these devices." "I'll be very glad to do it, sir," Dr. Lowry told him, "after I've been released from my present assignment." "Yes ... you take no more chances than we do." Mr. Green raised his right hand, held the disk facing the phone field. After a moment, the light in Dr. Lowry's living room darkened, turned to a rich, deep purple, gradually lightened again. Mr. Green took his hand down. "Are you convinced I'm the person I appear to be?"