"These two"ll unscramble that broadcast," said Sergeant Bellews, with tranquil confidence. "Al"s learned how to make a tape and switch frequencies expert. Gus, here, he"s a unscrambler that can make any kinda scanning pattern. Together they"ll have a party doing what they"re special trained for. We"ll hook "em to Betsy"s training-terminals."
He regarded the two machines warmly. Connected, now, their standby lights flickered at a new tempo. They synchronized, and broke synchrony, and went back into elaborate, not-quite-resolvable patterns which were somehow increasingly integrated as seconds went by.
"Those lights look kinda nice, don"t they?" asked the sergeant admiringly. "Makes you think of a coupla dogs gettin" acquainted when they"re goin" out on a job of hunting or something."
But Lecky said abruptly, in amazement:
"But, Sergeant! In the Pentagon it takes days to unscramble a received broadcast such as Betsy receives! It requires experts--"
"Huh!" said Sergeant Bellews. He picked up the two machines. "Don"t get me started about the kinda guys that w.a.n.gle headquarters-company jobs!
They got a special talent for fallin" soft. But they haven"t necessarily got anything else!"
Lecky followed Sergeant Bellews as the sergeant picked up his new combination of devices and headed out of the Rehab Shop. Outside, in the sunshine, there were roarings to be heard. Lecky looked up. A formation of jets swam into view against the sky. A tiny speck, trailing a monstrous plume of smoke, shot upward from the jet-field. The formation tightened.
The ascending jet jiggled as if in pure exuberance as it swooped upward--but the jiggle was beautifully designed to throw standard automatic gunsights off.
A plane peeled off from the formation and dived at the ascending ship.
There was a curious alteration in the thunder of motors. The rate-of-rise of the climbing jet dwindled almost to zero. Sparks shot out before it. They made a cone the diving ship could not avoid. It sped through them and then went as if disappointedly to a lower level. It stood by to watch the rest of the dog-fight.
"Nice!" said Sergeant Bellews appreciatively. "That"s a Mahon jet all by itself, training against regular ships. They have to let it shoot star-bullets in training, or it"d get hot and bothered in a real fight when its guns went off."
The lower jet streaked skyward once more. Sparks sped from the formation. They flared through emptiness where the Mahon jet had been but now was not. It scuttled abruptly to one side as concerted streams of sparks converged. They missed. It darted into zestful, exuberant maneuverings, remarkably like a dog dashing madly here and there in pure high spirits. The formation of planes attacked it resolutely.
Suddenly the lone jet plunged into the midst of the formation, there were coruscations of little shooting stars, and one-two-three planes disgustedly descended to lower levels as out of action. Then the single ship shot upward, seemed eagerly to shake itself, plunged back--and the last ships tried wildly to escape, but each in turn was technically shot down.
The Mahon jet headed back for its own tiny airfield. Somehow, it looked as if, had it been a dog, it would be wagging its tail and panting happily.
"That one ship," said Lecky blankly, "it defeated the rest?"
"It"s got a lot of experience," said the sergeant. "You can"t beat experience."
He led the way into Communications Center. In the room where Betsy stood, Howell and Graves had been drawing diagrams at each other to the point of obstinacy.
"But don"t you see?" insisted Howell angrily. "There can be no source other than a future time! You can"t send short waves through three-dimensional s.p.a.ce to a given spot and not have them interceptible between. Anyhow, the Compubs wouldn"t work it this way! They wouldn"t put us on guard! And an extra-terrestrial wouldn"t pretend to be a human if he honestly wanted to warn us of danger! He"d tell us the truth!
Physically and logically it"s impossible for it to be anything but what it claims to be!"
Graves said doggedly:
"But a broadcast originating in the future is impossible!"
"Nothing," snapped Howell, "that a man can imagine is impossible!"
"Then imagine for me," said Graves, "that in 2180 they read in the history books about a terrible danger to the human race back in 1972, which was averted by a warning they sent us. Then, from their history-books, which we wrote for them, they learn how to make a transmitter to broadcast back to us. Then they tell us how to make a transmitter to broadcast ahead to them. They don"t invent the transmitter. We tell them how to make it--via a history book. We don"t invent it. They tell us--from the history book. Now imagine for me how that transmitter got invented!"
"You"re quibbling," snapped Howell. "You"re refusing to face a fact because you can"t explain it. I say face the fact and then ask for an explanation!"
"Why not ask them," said Graves, "how to make a round square or a five-sided triangle?"
Sergeant Bellews pushed to a spot near Betsy. He put down his now-linked Mahon machines and began to move away some of the recording apparatus focused on Betsy.
"Hold on there!" said Howell in alarm. "Those are recorders!"
"We"ll let "em record direct," said the sergeant.
Lecky spoke feverishly in support of Bellews. But what he said was, in effect, a still-marveling description of the possibilities of Mahon-modified machines. They were, he said with ardent enthusiasm, the next step in the historic process by which successively greater portions of the cosmos enter into a symbiotic relationship with man. Domestic animals entered into such a partnership aeons ago. Certain plants--wheat and the like--even became unable to exist without human attention. And machines were wrought by man and for a long time served him reluctantly.
Pre-Mahon machines were tamed, not domestic. They wore themselves out and destroyed themselves by accidents. But now there were machines which could enter into a truly symbiotic relationship with humanity.
"What," demanded Howell, "what in h.e.l.l are you talking about?"
Lecky checked himself. He smiled abashedly:
"I think," he said humbly, "that I speak of the high destiny of mankind.
But the part that applies at the moment is that Sergeant Bellews must not be interfered with."
He turned and ardently a.s.sisted Sergeant Bellews in making room for the just-brought devices. Sergeant Bellews led flexible cables from them to Betsy. He inserted their leads in her training-terminals. He made adjustments within.
It became notable that Betsy"s standby light took up new tempos in its wavering. There were elaborate interweavings of rate and degree of brightening among the lights of all three instruments. There was no possible way to explain the fact, but a feeling of pleasure, of zestful stirring, was somehow expressed by the three machines which had been linked together into a cooperating group.
Sergeant Bellews eased himself into a chair.
"Now everything"s set," he observed contentedly. "Remember, I ain"t seen any of these broadcasts unscrambled. I don"t know what it"s all about.
But we got three Mahon machines set up now to work on the next crazy broadcast that comes in. There"s Betsy and these two others. And all machines work accordin" to the Golden Rule, but Mahon machines--they are honey-babes! They"ll bust themselves tryin" to do what you ask "em. And I asked these babies for plenty--only not enough to hurt "em. Let"s see what they turn out."
He pulled a pipe and tobacco from his pocket. He filled the pipe. He squeezed the side of the bowl and puffed as the tobacco glowed. He relaxed, underneath the wall-sign which sternly forbade smoking by all military personnel within these premises.
It was nearly three hours--but it could have been hundreds--before Betsy"s screen lighted abruptly.
The broadcast came in; a new transmission. The picture-pattern on Betsy"s screen was obviously not the same as other broadcasts from nowhere. The chirps and peepings and the rumbling deep sounds were not repet.i.tions of earlier noise-sequences. It should have taken many days of finicky work by technicians at the Pentagon before the originally broadcast picture could be seen and the sound interpreted. But a play-back recorder named Al, and a picture-unscrambler named Gus were in closed-circuit relationship with Betsy. She received the broadcast and they unscrambled the sound and vision parts of it immediately.
The translated broadcast, as Gus and Al presented it, was calculated to put the high bra.s.s of the defense forces into a frenzied tizzy. The anguished consternation of previous occasions would seem like very calm contemplation by comparison. The high bra.s.s of the armed forces should grow dizzy. Top-echelon civilian officials should tend to talk incoherently to themselves, and scientific consultants--biologists in particular--ought to feel their heads spinning like tops.
The point was that the broadcast had to be taken seriously because it came from nowhere. There was no faintest indication of any signal outside of Betsy"s sedately gray-painted case. But Betsy was not making it up. She couldn"t. There was a technology involved which required the most earnest consideration of the message carried by it.
And this broadcast explained the danger from which the alleged future wished to rescue its alleged past. A brisk, completely deracialized broadcaster appeared on Gus"s screen.
In clipped, oddly stressed, but completely intelligible phrases, he explained that he recognized the paradox his communication represented.
Even before 1972, he observed, there had been argument about what would happen if a man could travel in time and happened to go back to an earlier age and kill his grandfather. This communication was an inversion of that paradox. The world of 2180 wished to communicate back in time and save the lives of its great-great-great-grandparents so that it--the world of 2180--would be born.
Without this warning and the information to be given, at least half the human race of 1972 was doomed.