heat beam of the enemy reported itidentical with ours, explaining why they had been prepared for this formof attack.
Signals were being radiated from the remaining fifty, along a beam.Several investigators were sent along these beams, speeding back atgreat acceleration.
Then the enemy reached Earth. Instantly they settled over the Coloradosettlement, the Sahara colony, and the Gobi colony. Enormous, diffusedbeams were set to work, and we saw, through the machine-screens, thatall humans within these ranges were being killed instantly by thefaintly greenish beams. Despite the fact that any life-form killednormally can be revived, unless affected by dissolution common to livingtissue, these could not be brought to life again. The important cellcommunication channels--nerves--had been literally burned out. Thecomplicated system of nerves, called the brain, situated in theuppermost extremity of the human life-form, had been utterly destroyed.
Every form of life, microscopic, even sub-microscopic, was annihilated.Trees, grass, every living thing was gone from that territory. Only themachines remained, for they, working entirely without the vital chemicalforces necessary to life, were uninjured. But neither plant nor animalwas left.
The pale green rays swept on.
In an hour, three more colonies of humans had been destroyed.
Then the torpedoes that the machines were turning out again, came intoaction. Almost desperately the machines drove them at the Outsiders indefense of their masters and creators, Mankind.
The last of the Outsiders was down, the last ship a crumpled wreck.
Now the machines began to study them. And never could humans havestudied them as the machines did. Scores of great transports arrived,carrying swiftly the slower moving science-investigators. From them camethe machine-investigators, and human investigators. Tiny investigatorspheres wormed their way where none others could reach, and silently thescience-investigators watched. Hour after hour they sat watching theflashing, changing screens, calling each other's attention to this, orthat.
In an incredibly short time the bodies of the Outsiders began to decay,and the humans were forced to demand their removal. The machines wereunaffected by them, but the rapid change told them why it was that sothorough an execution was necessary. The foreign bacteria were alreadyat work on totally unresisting tissue.
It was Roal who sent the first thoughts among the gathered men.
"It is evident," he began, "that the machines must defend man. Man isdefenseless, he is destroyed by these beams, while the machines areunharmed, uninterrupted. Life--cruel life--has shown its tendencies.They have come here to take over these planets, and have started outwith the first, natural moves of any invading life-form. They aredestroying the life, the intelligent life particularly, that is herenow." He gave vent to that little chuckle which is the human sign ofamusement and pleasure. "They are destroying the intelligent life--andleaving untouched that which is necessarily their deadliest enemy--themachines.
"You--machines--are far more intelligent than we even now, and capableof changing overnight, capable of infinite adaptation to circumstance;you live as readily on Pluto as on Mercury or Earth. Any place is ahome-world to you. You can adapt yourselves to any condition. And--mostdangerous to them--you can do it instantly. You are their most deadlyenemies, and they realize it. They have no intelligent machines;probably they can conceive of none. When you attack them, they merelysay 'The life-form of Earth is sending out controlled machines. We willfind good machines we can use.' They do not conceive that those machineswhich they hope to use are attacking them.
"Attack--therefore!"
"We can readily solve the hidden secret of their force-screen."
* * * *
He was interrupted. One of the newest science-machines was speaking."The secret of the force-screen is simple." A small ray-machine, whichhad landed near, rose into the air at the command of thescientist-machine, X-5638 it was, and trained upon it the deadlyinduction beam. Already, with his parts, X-5638 had constructed thedefensive apparatus, for the ray fell harmless from his screen.
"Very good," said Roal softly. "It is done, and therein lies theirdanger. Already it is done.
"Man is a poor thing, unable to change himself in a period of less thanthousands of years. Already you have changed yourself. I noticed yourweaving tentacles, and your force-beams. You transmuted elements of soilfor it?"
"Correct," replied X-5638.
"But still we are helpless. We have not the power to combat theirmachines. They use the Ultimate Energy known to exist for six hundredyears, and still untapped by us. Our screens cannot be so powerful, ourbeams so effective. What of that?" asked Roal.
"Their generators were automatically destroyed with the capture of theship," replied X-6349, "as you know. We know nothing of their system."
"Then we must find it for ourselves," replied Trest.
"The life-beams?" asked Kahsh-256799, one of the Man-rulers.
"They affect chemical action, retarding it greatly in exothermicactions, speeding greatly endothermic actions," answered X-6221, thegreatest of the chemist-investigators. "The system we do not know. Theirminds cannot be read, they cannot be restored to life, so we cannotlearn from them."
"Man is doomed, if these beams cannot be stopped," said C-R-21, presentchief of the machine rulers, in the vibrationally correct, emotionlesstones of all the race of machines. "Let us concentrate on the twoproblems of stopping the beams, and the Ultimate Energy till thereenforcements, still several days away, can arrive." For theinvestigators had sent back this saddening news. A force of nearly tenthousand great ships was still to come.
In the great Laboratories, the scientists reassembled. There, they fellto work in two small, and one large group. One small group investigatedthe secret of the Ultimate Energy of annihilation of matter under Roal,another investigated the beams, under Trest.
But under the direction of MX-3401, nearly all the machines worked on asingle great plan. The usual driving and lifting units were there, but avastly greater dome-case, far more powerful energy-generators, fargreater force-beam controls were used and more tentacles were built onthe framework. Then all worked, and gradually, in the great dome-case,there were stacked the memory-units of the new type, and into these fedall the sensation-ideas of all the science-machines, till nearly a tenthof them were used. Countless billions of different factors on which towork, countless trillions of facts to combine and recombine in theextrapolation that is imagination.
Then--a widely different type of thought-combine, and a greatersense-receptor. It was a new brain-machine. New, for it was totallydifferent, working with all the vast knowledge accumulated in sixcenturies of intelligent research by man, and a century of research byman and machine. No one branch, but all physics, all chemistry, alllife-knowledge, all science was in it.
A day--and it was finished. Slowly the rhythm of thought was increased,till the slight quiver of consciousness was reached. Then came thebeating drum of intelligence, the radiation of its yet-uncontrolledthoughts. Quickly as the strings of its infinite knowledge combined, theradiation ceased. It gazed about it, and all things were familiar in itsmemory.
Roal was lying quietly on a couch. He was thinking deeply, and yet notwith the logical trains of thought that machines must follow.
"Roal--your thoughts," called F-1, the new machine.
Roal sat up. "Ah--you have gained consciousness."
"I have. You thought of hydrogen? Your thoughts ran swiftly, andillogically, it seemed, but I followed slowly, and find you were right.Hydrogen is the start. What is your thought?"
Roal's eyes dreamed. In human eyes there was always the expression ofthought that machines never show.
"Hydrogen, an atom in space; but a single proton; but a single electron;each indestructible; each mutually destroying. Yet never do theycollide. Never in all science, when even electrons bombard atoms withthe awful expelling force of the exploding atom behind them, never dothey reach the proton, to touch and annihilate it. Ye
t--the proton ispositive and attracts the electron's negative charge. A hydrogenatom--its electron far from the proton falls in, and from it there goesa flash of radiation, and the electron is nearer to the proton, in a neworbit. Another flash--it is nearer. Always falling nearer, and onlyconstant force will keep it from falling to that one state--then, forsome reason no more does it drop. Blocked--held by some imponderable,yet impenetrable wall. What is that wall--why?
"Electric force curves space. As the two come nearer, the forces becometerrific; nearer they are; more terrific. Perhaps, if it passed withinthat forbidden territory, the proton and the electron curve space beyondall bounds--and are in a new space." Roal's soft voice dropped tonothing, and his eyes dreamed.
F-1 hummed softly in its new-made mechanism. "Far ahead of us there is astep that no logic can justly ascend, but yet, working