I cannot remember following Pollard and Dutton to the laboratory, my thoughts were spinning so at the time. It was not until we stood before the great cube from which the huge metal cylinder towered that I was aware of the reality of it all.

Pollard had gone into the dynamo-room and as Dutton and I stared wordlessly at the great cube and cylinder, at the retorts and flasks of acids and strange equipment about us, we heard the hum of motor-generators. Pollard came back to the switchboard supported in a steel frame beside the cube, and as he closed a switch there there came a crackling and the cylinder glowed with white light.

Pollard pointed to it and the big quartz-like disk in the cubical chamber's ceiling, from which the white force-shafts shot downward.

"The cylinder is now gathering cosmic rays from an immense area of space," he said, "and those concentrated rays are falling through that disk into the cube's interior. To cut off the rays it is necessary only to open this switch." He reached to open the switch, the light died.

THE MAN WHO EVOLVED

Quickly, while we stared, he removed his clothing, donning in place of it a loose white running suit.

"I will want to observe the changes of my own body as much as possible," he explained. "Now, I will stand inside the cube and you will turn on the rays and let them play upon me for fifteen minutes. Roughly, that should represent a period of some fifty million years of future evolutionary change. At the end of fifteen minutes you will turn the rays off and we will be able to observe what changes they have caused. We will then resume the process, going forward by fifteen-minute or rather fifty-million-year periods."

"But where will it stop — where will we quit the process?" Dutton asked.

Pollard shrugged. "We'll stop where evolution stops, that is, where the rays no longer affect me. You know, biologists have often wondered what the last change or final development of man will be, the last mutation. Well, we are going to see tonight what it will be."

He stepped toward the cube and then paused, went to a desk and brought from it a sealed envelope he handed to me.