Ken pressed a button. A section of the glass top slid smoothly underneath, leaving the tank exposed just wide enough to admit a human body. Above it, suspended from a miniature crane, was a cradle of extremely thin, longitudinally stretched wires. At a gesture from Ken, the guards lifted the immobile body of the condemned man, deposited it carefully into the cradle.

Then he knifed a switch. There was a whir, and the cradle, with its strange burden, dipped slowly from unwinding chains into the transparent substance within the tank. Down, down, ever down, while the men in the room stared with fixed, unwilling fascination.

The jelly closed with a quiver over the descending form. Within its clear depths the cradled body showed like a prehistoric monster caught in a huge globule of ancient amber...

(Nutrient Gelatin Tank from 'The Isotope Men' by Nat Schachner)

Stubbs moved quickly to the instrument panel. For an instant his long, bony fingers clung with fierce grip to the bakelite handle of the master switch. His eyes burned through the transparency of the tank, fixed with a fanatical light on the quiescent body within.

The future of the world rested on the tug of his hand. If the experiment proved a success, his name would go rocketing down the centuries. Darwin, Newton, Einstein, Galileo would be pale, glimmering phantoms compared to him.

A TREMENDOUS current surged through the electrodes. The jelly, at their base, stirred uneasily, blurred slightly with tiny bubbles.

Jim Horty was no longer a solid, compact body. He had lost shape and substance. He was stretching out along the plane of vibration in a tenuous, ghostlike flow; he was blurred and misty and unrecognizable; he was a parallelepiped of former length and thickness, but already he was three feet wide and expanding visibly.

There was no evidence of the man they had called James Horty any more. He had been swallowed up, ingested seemingly into the horrible plasma that filled the quartzite interior, that was quivering now and bubbling in a veritable witches' broth. Faintly, halfway down the tank, was an amorphous cloud.

"It is really quite simple," the scientist explained patiently. "The human body, protoplasm, bone structure and all, is composed chiefly of six elements. Carbon, hydrogen, oxygen, nitrogen, sulphur, and calcium, with a scattering of others. Every one of these has been dissociated into its isotopes. They exist, as far as we know, in indisseverable mixture. But suppose that isn't so. Suppose that some internal mechanism exists in the human body, in each cell, which under certain rare conditions, clicks, and dissociates the isotopes. We already know much about the genes of inheritance within the cell nucleus. We know that there are present, side by side, genes of opposing inherited characters. The stronger, or dominant gene will mask the recessive characters, as if they did not exist. Yet, in the next generation, perhaps, the recessive gene, by proper association, may in turn mask the dominant characteristic."

"Why then, I thought," Stubbs went on, "might not the isotopes of the ele- ments in the human body act the same way? Those present in the largest quantity would be dominant, the others recessive. Less than one per cent are the isotopes; the other ninety-nine per cent what we had heretofore considered the entire element. Suppose, as in the case of recessive genes, something happens, and the minority isotopes suddenly mask the dominant norm. What would you have?"

The doctor's eyes bulged. "Why, 1 — I'd say you'd have a different personality. The other part of what we've called dual personalities."

"Exactly," Stubbs declared triumphantly.

"How put it into practice?" Stubbs finished for him. "Easiest thing in the world. The technique for separating isotopes is pretty well established by now. I've improved on it immensely. I've done more than merely shift isotopes within the body. I'm able to separate them entirely, make two separate human bodies, two separate entities, where one existed before, each composed of a unit set of isotopes. I've done what nature has merely fumbled at doing. I've taken the two personalities and clothed them in visible form for the first time in the history of the universe !"

"In that tank," pursued the scientist, "is a nutrient gelatin, properly treated to carry an electric current. The injection I gave Horty contained, beside a powerful narcotic, a saline solution to promote conductivity within his body. I am passing a current of extremely high amperage and low voltage through the gelatin. The body dissociates into ions, and, following the laws of electrolytic separation, these ions migrate through the gelatin very slowly from the positive to the negative electrode.