"There is evidence that the poles of our world have changed and that this northern region was once close to being tropical. Any catastrophe violent enough to bring about a switch in the poles of this planet might well have wiped out all traces of a civilization, no matter how superior. We have good reason to believe that such a people must have existed, but we must find them.

"And Ashe is a convert from the skeptics—" the major slipped down from his perch on the wall shelf—"he is an archaeologist, one of your tomb discoverers, and knows what he is talking about. We must do our hunting in time earlier than the first pyramid, earlier than the first group of farmers who settled by the Tigris River. But we have to let the enemy guide us to it. That's where you come in."

"Why me?"

"That is a question to which our psychologists are still trying to find the answer, my young friend. It seems that the majority of the people of the several nations linked together in this project have become too civilized. The reactions of most men to given sets of circumstances have become set in regular patterns and they cannot break that conditioning, or if personal danger forces them to change those patterns, they are afterward so adrift they cannot function at their highest potential. Teach a man to kill, as in war, and then you have to recondition him later.

"But during these same wars we also develop another type. He is the born commando, the secret agent, the expendable man who lives on action. There are not many of this kind, and they are potent weapons. In peacetime that particular collection of emotions, nerve, and skills becomes a menace to the very society he has fought to preserve during a war. He is pressured by the peaceful environment into becoming a criminal or a misfit.

"The men we send out from here to explore the past are not only given the best training we can possibly supply for them, but they are all of the type once heralded as the frontiersman. History is sentimental about that type—when he is safely dead—but the present finds him difficult to live with. Our time agents are misfits in the modern world because their inherited abilities are born out of season now. They must be young enough and possess a certain brand of intelligence to take the stiff training and to adapt, and they must pass our tests. Do you understand?"

Ross nodded. "You want crooks because they are crooks——"

"No, not because they are crooks, but because they are misfits in their time and place. Don't, I beg of you, Murdock, think that we are operating a penal institution here. You would never have been recruited if you hadn't tested out to suit us. But the man who may be labeled murderer in his own period might rank as a hero in another, an extreme example, but true. When we train a man he not only can survive in the period to which he is sent, but he can also pass as a native born in that era——"

"What about Hardy?"

The major gazed into space. "There is no operation which is foolproof. We have never said that we don't run into trouble or that there is no danger in this. We have to deal with both natives of different times, and if we are lucky and hit a hot run, with the Reds. They suspect that we are casting about, hunting their trail. They managed to plant Kurt Vogel on us. He had an almost perfect cover and conditioning. Now you have it straight, Murdock. You satisfy our tests, and you'll be given a chance to say yes or no before your first run. If you say no and refuse duty, it means you must become an exile and stay here. No man who has gone through our training can return to normal life; there is too much chance of his being picked up and sweated by the opposition."