“Great Snell!” he gasped. “So that was it! I ran into a temporal snag!”

Looking backward later, Oliver thought that in that moment, for the first time clearly, he began to suspect the truth. But he had no time to ponder it, for after the brief instant of enmity the three people from—elsewhere—began to speak all at once, as if in a belated attempt to cover something they did not want noticed.

It was sensitive enough to pick up the “fingerprints” of light and sound waves imprinted on matter, descramble and screen them, and reproduce the image of what had happened.

But lots of things were crazier and some bigger, nd now they’re commonplace.