Russell Page squinted thoughtful eyes at the thing he had created--a transparent cloud, a visible, sharply outlined cloud of _something_. It was visible as a piece of glass is visible, as a globe of water is visible. There it lay, within his apparatus, a thing that shouldn't be. "I believe we have something there, Harry," he said slowly. Harry Wilson sucked at the cigarette that drooped from the corner of his mouth, blew twin streams of smoke from his nostrils. His eyes twitched nervously. "Yeah," he said. "Anti-entropy." "All of that," said Russell Page. "Perhaps a whole lot more." "It stops all energy change," said Wilson, "as if time stood still and things remained exactly as they were when time had stopped." "It's more than that," Page declared. "It conserves not only energy _in toto_, not only the energy of the whole, but the energy of the part. It is perfectly transparent, yet it has refractive qualities. It won't absorb light because to do so would change its energy content. In that field, whatever is hot stays hot, whatever is cold can't gain heat." He scraped his hand over a week's growth of beard, considering. From his pocket he took a pipe and a leather pouch. Thoughtfully he filled the pipe and lit it. It had started with his experiments in Force Field 348, an experiment to observe the effects of heating a conductor in that field. It had been impossible to heat the conductor electrically, for that would have upset the field, changed it, twisted it into something else. So he had used a Bunsen burner. Through half-closed eyes, he still could see that slender strand of imperm wire, how its silvery length had turned to red under the blue flame. Deep red at first and then brighter until it flamed in almost white-hot incandescence. And all the while the humming of the transformer as the force field built up. The humming of the transformer and the muted roaring of the burner and the glowing heat in the length of wire. Something had happened then ... an awesome something. A weird wrench as if some greater power, some greater law had taken hold. A glove of force, invisible, but somehow sensed, had closed about the wire and flame. Instantly the roaring of the burner changed in tone; an odor of gas spewed out of the vents at its base. Something had cut off the flow of flame in the brass tube. Some force, _something_ ... The flame was a transparent cloud. The blue and red of flame and hot wire had changed, in the whiplash of a second, to a refractive but transparent cloud that hung there within the apparatus. * * * * *