The clock, we learned, starts when you arrive the first time, and it does not reset if you return again. He, and we, assumed at the time that he had two weeks a trip. He didn’t. So he’s there now, for all time, a meek, mild Franciscan monk in a monastery in northern Italy, a pudgy little Italian native of the time. To give you a final idea of how absolute absorption is, Dr. Small was also black—in our time.”

Ron Moosic whistled. “So then how do you get the recordings and pictures?”

“They tend to have a stronger sense of shape and substance, being inanimate. We’ve discovered that recorders and the like can be retained for almost the safety period. Weapons, on the other hand, tend to be absorbed into period weapons rather quickly. One supposes that a battery-powered recorder has a minimal chance of affecting history, while a new weapon or something else of that sort could do a great deal of damage. Why and how such judgments are made by nature we don’t know at all. Why is the speed of light so absolute even time must bend before it? We don’t know. It just is, that’s all.”

“Still, the old saw about going back and killing your own father before he met your mother still holds. How can you do that and still exist? And if you didn’t exist, you couldn’t go back.”

“But you could. We haven’t actually had a test, but this absorption phenomenon seems designed mostly to counter that sort of thing. In theory, you would in fact cease to exist in the present as soon as you committed the deed, which would snap your energy link. You would then become, immediately, this wholly new personality, this created individual. Joe would become time-frame John, and it would be John, not Joe, who shot the man who would have become Joe’s father. Of course, John would create a ripple that would then wipe out Joe, or so we believe, but the deed would still be done.”

“It would seem, then, that there’s very little to worry about in all this,” Moosic commented. “The only real risk is to our time traveler, not our present.”