"And now," Ggaran put in, "I think it's time for you to tell us something about how you get across light-years of space in a few hours, without leaving any traces for us to detect." He raised a tentacle to still Crownwall's immediate exclamation of protest. "Oh, nothing that would give us a chance to duplicate it--just enough to _indicate_ how we can make use of it, along with you--enough to allow us to _begin_ to make intelligent plans to beat the claws off the Master Race." * * * * * After due consideration, Crownwall nodded. "I don't see why not. Well, then, let me tell you that we don't travel in space at all. That's why I didn't show up on any of your long-range detection instruments. Instead, we travel in time. Surely any race that has progressed as far as your own must know, at least theoretically, that time travel is entirely possible. After all, we knew it, and we haven't been around nearly as long as you have." "We know about it," said Ffallk, "but we've always considered it useless--and very dangerous--knowledge." "So have we, up until the time you planted that bomb on us. Anyone who tried to work any changes in his own past would be almost certain to end up finding himself never having been born. So we don't do any meddling. What we have discovered is a way not only of moving back into the past, but also of making our own choice of spatial references while we do it, and of changing our spatial anchor at will. "For example, to reach this planet, I went back far enough, using Earth as the spatial referent, to move with Earth a little more than a third of the way around this spiral nebula that is our Galaxy. Then I shifted my frame of reference to that of the group of galaxies of which ours is such a distinguished member. "Then of course, as I continued to move in time, the whole Galaxy moved spatially with reference to my own position. At the proper instant I shifted again, to the reference frame of this Galaxy itself. Then I was stationary in the Galaxy, and as I continued time traveling, your own mighty sun moved toward me as the Galaxy revolved. I chose a point where there was a time intersection of your planet's position and my own. When you got there, I just changed to the reference plane of this planet I'm on now, and then came on back with it to the present. So here I am. It was a long way around to cover a net distance of 26 light-years, but it was really very simple. "And there's no danger of meeting myself, or getting into any anachronistic situation. As you probably know, theory shows that these are excluded times for me, as is the future--I can't stop in them." "Are you sure that you haven't given us a little too much information for your own safety?" asked Ffallk softly.