The Secretary-General of the United Nations beamed. "Thus preventing the Blight, making it nonexistent, as it were, producing a present-day world in which the Blight never occurred. That is correct, is it not, gentlemen?" he asked, turning anxiously again. * * * * * None of the half-dozen men on couches deigned to answer him. And Alben kept his eyes deferentially in their direction, too, as he had throughout this period of last-minute instruction. He knew who ruled his world--these stolid, well-fed men in clean garments with a minimum of patches, and where patches occurred, at least they were the color of the surrounding cloth. Sadha might be Secretary-General of the United Nations, but that was still a civil-service job, only a few social notches higher than a chicken guard. His clothes were fully as ragged, fully as multi-colored, as those that Alben had stepped out of. And the gnawing in his stomach was no doubt almost as great. "You understand, do you not, young man, that if anything goes wrong," Abd Sadha asked, his head nodding tremulously and anticipating the answer, "if anything unexpected, unprepared-for, occurs, you are not to continue with the experiment but return immediately?" "He understands everything he has to understand," Gomez told him. "Let's get this thing moving." The old man smiled again. "Yes. Of course, Mr. Gomez." He came up to where Alben stood in the entrance of the time machine and handed the sealed metal cylinder to him. "This is the precaution the scientists have just added. When you arrive at your destination, just before materializing, you will release it into the surrounding temporal medium. Our purpose here, as you no doubt--" Levney sat up on his couch and snapped his fingers peremptorily. "I just heard Gomez tell you to get this thing moving, Sadha. And it isn't moving. We're busy men. We've wasted enough time." "I was just trying to explain a crucial final fact," the Secretary-General apologized. "A fact which may be highly--" "You've explained enough facts." Levney turned to the man inside the time machine. "Hey, fella. You. _Move!_" Max Alben gulped and nodded violently. He darted to the rear of the machine and turned the dial which activated it. _flick!_ * * * * * It was a good job and Mac Albin knew whom he had to thank for it--his great-grandfather. "Good old Giovanni Albeni," he laughed as he looked at the morose faces of his two colleagues. Bob Skeat and Hugo Honek had done as much as he to build the tiny time machine in the secret lab under the helicopter garage, and they were fully as eager to go, but--unfortunately for them--they were not descended from the right ancestor.