His eyes seemed to read us. "You need not fear now the things I threatened in my last stage of development. My mind, grown infinitely greater, would no more now want to rule you men and your little planet than you would want to rule an anthill and its inhabitants!
My mind, gone fifty million years further ahead in development, can soar out now to vistas of power and knowledge unimagined by me in that last stage, and unimaginable to you."
"Great God, Pollard!" I cried. "What have you become?"
"Pollard?" Dutton was laughing hysterically. "You call that thing Pollard? Why, we had dinner with Pollard three hours ago — he was a human being, and not a thing like this!"
"I have become what all men will become in time," the thing's thought answered me. "I have gone this far along the road of man's future evolution, and am going on to the end of that road, am going to attain the development that the last mutation possible will give me!"
"Turn on the rays," his thought continued. "I think that I must be approaching now the last possible mutation."
I snapped over the switch again and the white shaft of the concentrated rays veiled from us the great gray shape. I felt my own mind giving beneath the strain of horror of the last hour, and Dutton was still half-hysterical.
The humming and crackling of the great apparatus seemed thunderous to my ears as the minutes passed. With every nerve keyed to highest tension, I threw open the switch at last. The rays ceased, and the figure in the chamber was again revealed.
Dutton began to laugh shrilly, and then abruptly was sobbing. I do not know whether I was doing the same, though I have a dim memory of mouthing incoherent things as my eyes took in the shape in the chamber.
It was a great brain! A gray limp mass four feet across, it lay in the chamber, its surface ridged and wrinkled by innumerable fine convolutions. It had no features or limbs of any kind in its gray mass. It was simply a huge brain whose only visible sign of life was its slow twitching movement.
From it thoughts beat strongly into our own horror-weighted brains.
"You see me now, a great brain only, just as all men will be far in the future. Yes, you might have known, I might have known, when I was like you, that this would be the course of human evolution, that the brain that alone gives man dominance would develop and the body that hampers that brain would atrophy until he would have developed into pure brain as I now am!
"I have no features, no senses that I could describe to you, yet can realize the universe infinitely better than you can with your elementary senses. I am aware of planes of existence you cannot imagine. I can feed myself with pure energy without the need of a cumbersome body, to transform it, and I can move and act, despite my lack of limbs, by means and with a speed and power utterly beyond your comprehension.
"If you still have fear of the threats I made two stages back against your world and race, banish them! I am pure intelligence now and as such, though I can no more feel the emotions of love or friendship, neither can I feel those of ambition or pride. The only emotion, if such it is, that remains to me still is intellectual curiosity, and this desire for truth that has burned in man since his apehood will thus be the last of all desires to leave him!"
"A brain — a great brain!" Dutton was saying dazedly. "Here in Pollard's laboratory — but where's Pollard? He was here, too. ."
"Then all men will some day be as you are now?" I cried.
"Yes," came the answering thought, "in two hundred and fifty million years man as you know him and as you are will be no more, and after passing all the stages through which I have passed through tonight, the human race will have developed into great brains inhabiting not only your solar system, no doubt, but the systems of other stars!"
"And that's the end of man's evolutionary road? That is the highest point that he will reach?"
"No, I think he will change still from those great brains into still a higher form," the brain answered — the brain that three hours before had been Pollard! — "and I am going to find out now what that higher form will be. For I think this will be the last mutation of all and that with it I will reach the end of man's evolutionary path, the last and highest form into which he can develop!
"You will turn on the rays now," the brain's order continued, "and in fifteen minutes we will know what that last and highest form is."
My hand was on the switch but Dutton had staggered to me, was clutching my arm. "Don't, Arthur!" he was exclaiming thickly. "We've seen horrors enough — let's not see the last — get out of here…"
"I can't!" I cried. "Oh God, I want to stop but I can't now — I want to see the end myself — I've got to see.."
"Turn on the rays!" came the brain's thought-order again.
"The end of the road — the last mutation," I panted. "We've got to see — to see—" I drove the switch home.
The rays flashed down again to hide the great gray brain in the cube. Dutton's eyes were staring fixedly, he was clinging to me.
The minutes passed! Each tick of the watch in my hand was the mighty note of a great tolling bell in my ears.
An inability to move seemed gripping me. The hand of my watch was approaching the minute for which I waited, yet I could not raise my hand toward the switch!
Then as the hand reached the appointed minute I broke from my immobility and in a sheer frenzy of sudden strength pulled open the switch, rushed forward with Dutton to the cube's very edge!
The great gray brain that had been inside it was gone. There lay on the cube's floor instead of it a quite shapeless mass of clear, jelly-like matter. It was quite motionless save for a slight quivering. My shaking hand went forth to touch it, and then it was that I screamed, such a scream as all the tortures of hell's crudest fiends could not have wrung from a human throat.
The mass inside the cube was a mass of simple protoplasm! This then was the end of man's evolution-road, the highest form to which time would bring him, the last mutation of all! The road of man's evolution was a circular one, returning to its beginning!
From the earth's bosom had risen the first crude organisms. Then sea-creature and land-creature and mammal and ape to man; and from man it would rise in the future through all the forms we had seen that night. There would be super-men, bodiless heads, pure brains; only to be changed by the last mutation of all into the protoplasm from which first it had sprung!
I do not know now exactly what followed. I know that I rushed upon that quivering, quiescent mass, calling Pollard's name madly and shouting things I am glad I cannot remember. I know that Dutton was shouting too, with insane laughter, and that as he struck with lunatic howls and fury about the laboratory the crash of breaking glass and the hiss of escaping gases was in my ears. And then from those mingling acids bright flames were leaping and spreading sudden fires that alone, I think now, saved my own sanity.
For I can remember dragging the insanely laughing Dutton from the room, from the house, into the cool darkness of the night.
I remember the chill of dew-wet grass against my hands and face as the flames from Pollard's house soared higher. And I remember that as I saw Dutton's crazy laughter by that crimson light, I knew that he would laugh thus until he died.
* * *
So ends my narrative of the end that came to Pollard and Pollard's house. It is, as I said in the beginning, a narrative that I only can tell now, for Dutton has never spoken a sane word since. In the institution where he now is, they think his condition the result of shock from the fire, just as Pollard was believed to have perished in that fire. I have never until now told the truth.