“What sort of protection have you in mind?”
“Electrical discharges in the outer part of the Cloud causing sufficient ionization to prevent the entry of external radio waves. Such a protection would be as essential as the skull is to the human brain.”
Aniseed smoke was rapidly filling the room. Marlowe suddenly found his pipe too hot to hold and put it down gingerly.
“My God, you think this explains the rise of ionization in the atmosphere, when we switch on our transmitters?”
“That’s the general idea. We were talking earlier on about a feedback mechanism. That, I imagine, is just what the beast has got. If any external waves get in too deeply, then up go the voltages and away go the discharges until the waves can get in no farther.”
“But the ionization takes place in our own atmosphere.”
“For this purpose I think we can regard our atmosphere as a part of the Cloud. We know from the shimmering of the night sky that gas extends all the way from the Earth to the denser parts of the Cloud, the disk-like parts. In short we’re inside the Cloud, electronically speaking. That, I think, explains our communication troubles. At an earlier stage, when we were outside the Cloud, the beast didn’t protect itself by ionizing our atmosphere, but through its outer electronic shield. But once we got inside the shield the discharges began to occur in our own atmosphere. The beast has been boxing-in our transmissions.”
“Very fine reasoning, Chris,” said Marlowe.
“Hellish fine,” nodded Alexandrov.
“How about the one-centimetre transmissions? They went through all right,” Weichart objected.
“Although the chain of reasoning is getting rather long there’s a suggestion that one can make on that. I think it’s worth making because it suggests the next action we might take. It seems to me most unlikely that this Cloud is unique. Nature doesn’t work in unique examples. So let’s suppose there are lots of these beasts inhabiting the Galaxy. Then I would expect communication to occur between one cloud and another. This would imply that some wave-lengths would be required for external communication purposes, wave-lengths that could penetrate into the Cloud and would do no neurological harm.”
“And you think one centimetre may be such a wave-length?”
“That’s the general idea.”
“But then why was there no reply to our one-centimetre transmission?’ asked Parkinson.
“Perhaps because we sent no message. There’d be no point in replying to a perfectly blank transmission.”
“Then we ought to start sending pulsed messages on the one centimetre,” exclaimed Leicester. “But how can we expect the Cloud to decipher them?”
“That’s not an urgent problem to begin with. It will be obvious that our transmissions contain information — that will be clear from the frequent repetition of various patterns. As soon as the Cloud realizes that our transmissions have intelligent control behind them I think we can expect some sort of reply. How long will it take to get started, Harry? You’re not in a position to modulate the one centimetre yet, are you?”
“No, but we can be in a couple of days, if we work night shifts. I had a sort of presentiment that I wasn’t going to see my bed tonight. Come on, chaps, let’s get started.”
Leicester stood up, stretched himself, and ambled out. The meeting broke up. Kingsley took Parkinson on one side.
“Look, Parkinson,” he said, “there’s no need to go gabbling about this until we know more about it.”
“Of course not. The Prime Minister suspects I’m off my head as it is.”
“There is one thing that you might pass on, though. If London, Washington, and the rest of the political circus could get ten-centimetre transmitters working, it’s just possible that they might avoid the fadeout trouble.”
When Kingsley and Ann Halsey were alone later that night, Ann remarked:
“How on earth did you come on such an idea, Chris?”
“Well, it’s pretty obvious really. The trouble is that we’re all inhibited against such thinking. The idea that the Earth is the only possible abode of life runs pretty deep in spite of all the science fiction and kids’ comics. If we had been able to look at the business with an impartial eye we should have spotted it long ago. Right from the first, things have gone wrong and they’ve gone wrong according to a systematic sort of pattern. Once I overcame the psychological block, I saw all the difficulties could be removed by one simple and entirely plausible step. One by one the bits of the puzzle fitted into place. I think Alexandrov probably had the same idea, only his English is a bit on the terse side.”
“On the bloody terse side, you mean. But seriously, do you think this communication business will work?”
“I very much hope so. It’s quite crucial that it should.”
“Why do you say that?”
“Think of the disasters the Earth has suffered so far, without the Cloud taking any purposive steps against us. A bit of reflection from its surface nearly roasted us. A short obscuration of the Sun nearly froze us. If the merest tiny fraction of the energy controlled by the Cloud should be directed against us we should be wiped out, every plant and animal.”
“But why should that happen?”
“How can one tell? Do you think of the tiny beetle or the ant that you crush under your foot on an afternoon’s walk? One of those gas bullets that hit the Moon three months ago would finish us. Sooner or later the Cloud will probably let fly with some more of ’em. Or we might be electrocuted in some monstrous discharge.”
“Could the Cloud really do that?”
“Easily. The energy that it controls is simply enormous. If we can get some sort of a message across, then perhaps the Cloud will take the trouble to avoid crushing us under its foot.”
“But why should it bother?”
“Well, if a beetle were to say to you, “Please, Miss Halsey, will you avoid treading here, otherwise I shall be crushed,” wouldn’t you be willing to move your foot a trifle?”
Communication Established
Four days later after thirty-three hours of transmission from Nortonstowe the first communication from the Cloud came through. It would be idle to attempt to describe the prevailing excitement. Suffice it to say that frenzied attempts were made to decode the incoming message, for message it obviously was, judging from regular patterns that could be discovered among the rapid pulses of radio signal. The attempts were not successful. Nor was this surprising, for, as Kingsley remarked, it can be difficult enough to discover a code when the message has initially been thought out in a known language. Here the language of the Cloud was entirely unknown.
“That seems good sense to me,” remarked Leicester. “Our problem isn’t likely to be any easier than the Cloud’s problem, and the Cloud won’t understand our messages until it’s discovered the English language.”
“The problem’s probably a great deal worse than that,” said Kingsley. “We’ve every reason to believe that the Cloud is more intelligent than we are, so its language — whatever it may be — is likely to be a lot more complicated than ours. My proposal is that we stop bothering trying to decipher the messages we’ve been receiving. Instead I propose we rely on the Cloud being able to decipher our messages. Then when it’s learned our language it can reply in our own code.”
“Dam’ good idea. Always force foreigner to learn English,” said Alexandrov to Yvette Hedelfort.
“To begin with, I think we should stick as much as possible to science and mathematics because these are likely to be the best common denominator. Later on we can try sociological stuff. The big job will be to record all the material we want to transmit.”
“You mean that we ought to transmit a sort of basic course in science and mathematics, and in basic English?’ said Weichart.
“That’s the idea. And I think we ought to get down to it right away.”
The policy was successful, too successful. Within two days the first intelligible reply was received. It read:
