I mean by traveling between Space. We will assume a nearly two-dimensional universe in the form of a circular piece of paper three feet in diameter. There is a dot in the exact center of each side of this paper. To a two-dimensional creature, forced to travel only on the surface of the paper, the distance between the two dots can never be less than thirty-six inches. Yet by cutting between the two surfaces and going directly through the paper the dots are less than one-hundredth of an inch apart.

"Such is the case with Xollar and the planets in your universe which are our immediate neighbors in inter-dimensional Space. In order to reach those planets I had only to develop a method of using sufficient force to cut between the three dimensions of intervening Space. In solving this problem I developed both an inter-dimensional net to bring beings from your universe to mine, and an inter-dimensional gate to permit beings to pass from here back to worlds in your galaxy.

"You have already seen the workings of the net. It was the device of green fire that brought you here. The use of the net was a vital part of my plans, for without the use of a physical body from some world in your universe I could not hope to live longer than a few minutes after leaving Xollar via the inter-dimensional gate. The inherent characteristics and basic elements of your galaxy and the Andromedan universe are so different in every way that an inhabitant of either star-group cannot exist in the other. Xollar's purple atmosphere is characteristic of Andromedan worlds. Your oxygen-saturated air is typical of worlds in your galaxy. Just as Xollar's purple mists would be immediately fatal to you, so would your clear oxygen-tainted air be quickly fatal to me.

"Accordingly, my only chance of surviving in one of your worlds is to first transfer my Intelligence to the body of one of the dwellers upon that planet. Of the seven planets within reach of my net I found only two that promised to be at all suitable. One was your Earth, the other a minor planet circling the star you call Vega. I brought both you and a net-load of Vegans here to this oxygen-filled enclosure I had already prepared.

"The Vegans were the headless things with the jelly nuclei. I watched your battle with them, and waited to choose as my vehicle the planetary type that proved the stronger. You vanquished the Vegans, so it is in the body of an Earthling that I shall leave Xollar, and it is to the planet Earth that I shall be hurtled through the inter-dimensional gate.

"Aside from the slight difficulty caused by having to keep my body and yours each in its proper element during the operation, the matter of transfer into one of your bodies is a simple one. It involves none of the clumsy brain surgery of your Earthly science. We of Xollar have found that the real Intelligence of a being is an invisible force not at all dependent for existence upon the protoplasm through which it manifests. My Intelligence can function quite as well in your brain cells as in my own.

"I require no assistant in the transfer." Zehru indicated an intricate piece of apparatus on the platform behind him. It was a massive cylinder of fluorescent metal, with two long metallic cables running from its center, each cable ending in a saucer-shaped disk.

"I have only to thrust one cable through the force-wall into your enclosure and place its disk upon one of your heads, then place the other disk upon my own head. The apparatus is entirely automatic. Three seconds after both disks are in place my Intelligence will course into the Earthling brain, driving out his Intelligence and destroying it as mine enters.

"I will, of course, remove the selected body from under the paralyzing plate before I attach the disks. Then when I am safely transferred to the Earthling body I will have only to walk on through the enclosure to the silver arch at the far end and leave Xollar forever.

"That silver arch is the inter-dimensional gate to your Earth. Its operation is slightly different from that of the net. Where the net was capable of reaching under the surface of your planet, a proceeding I tried when two attempts upon the surface proved fruitless, the gate is so adjusted that it will place its passenger exactly upon the surface of your world. It requires no cooperation from this end. When I step under the arch I merely close a black lever there. Inter-dimensional force immediately catapults me to your Earth. Then the automatic mechanism of the gate will within half a minute of my departure release an explosion that will shatter everything within a radius of a mile here, and so prevent the Council of Three from even guessing the method of my escape."

"But what of the two of us whose bodies you do not need?" Blake protested. "Can you not at least take them through the arch-gate with you back to their home world?"

"Why should I do anything so foolish as that?" Zehru answered callously. "They might easily be a menace to my first attempts to establish myself upon your planet. Far better to leave them here in their present state of paralysis to be safely destroyed in the explosion of the gate."

Zehru now thrust three of his tentacles into a vat of milky fluid, and withdrew them coated with a silver sheen on the black flesh. The silver glaze seemed to be an insulation against both the oxygen of the enclosure and the paralyzing force of the overhead disk, for the Xollarian promptly thrust the three silver-coated arms through the wall and began handling the bodies of Mapes and Blake in a painstaking process of examination.

Again Blake noted that the shimmering gold-flecked wall closed quickly in and kept its surface unbroken no matter how often objects were thrust through it.

Completely ignoring Helen, Zehru lifted first Mapes, then Blake, his tentacles probing, fingering, exploring. There was enormous power in the Xollarian's grotesque body. He lifted the men as though they were wooden dolls, bringing them close to the shimmering wall to peer at them, then setting them carefully down again on their feet under the disk. Blake wondered idly why their stiff bodies did not topple over when they were left unsupported, then decided that the paralyzing force of the disk probably left the automatic muscular balancing movements unimpaired, affecting only the powers of voluntary movement.

Then, as Zehru set him down after one of the periods of examination, Blake noticed a new and startling change the moment his feet touched the ground. His right leg and right arm were no longer dead!

He hurriedly glanced down at the ground at his feet, and promptly found what seemed to be the reason for his partial freedom from the paralysis. In setting his body down the last time Zehru had moved Blake slightly. His right foot now rested upon a corner of the discarded topcoat lying half-buried there in the blue-gray dust.

The heavily rubberized cloth apparently acted as an insulating sheet that prevented the effective grounding of the paralyzing force that streamed down through Blake's body from the overhead disk. Consequently all portions of his body between the coat and the disk were free from the paralysis. For a moment Blake wondered at Zehru's carelessness. Then he realized that the insulating qualities of rubber would naturally be unknown to a Xollarian.

Noting that Zehru was busy at the moment with his work upon Mapes, Blake quickly grasped at the faint chance the presence of the rubberized cloth offered him. Working with infinite slowness and caution, he edged his right foot over an inch at a time, dragging the rest of his body with it.

Luck was with him. Zehru continued, absorbed in his work upon Mapes. The Xollarian's telepathic powers apparently functioned only with the aid of the red ray, for he remained oblivious of Blake's actions. One final cautious