“I’d like to know what the Rama Committee make of that,” Norton muttered to no one in particular. “Has anyone here got any theories?”
There was no time for an answer, because at that moment Hub Control called in great excitement.
“Resolution! Are you OK? Did you feel that?”
“Feel what?”
“We think it was an earthquake—it must have happened the minute those fireworks stopped.”
“Any damage?”
“I don’t think so. It wasn’t really violent but it shook us up a bit.”
“We felt nothing at all. But we wouldn’t, out here in the Sea.”
“Of course, silly of me. Anyway, everything seems quiet now… until next time.”
“Yes, until the next time,” Norton echoed.
The mystery of Rama was steadily growing; the more they discovered about it, the less they understood.
There was a sudden shout from the helm.
“Skipper—look—up there in the sky!”
Norton lifted his eyes, swiftly scanning the circuit of the Sea. He saw nothing, until his gaze had almost reached the zenith, and he was staring at the other side of the world.
“My God,” he whispered slowly, as he realized that the “next time” was already almost here.
A tidal wave was racing towards them, down the eternal curve of the Cylindrical Sea.
32. The Wave
Yet even in that moment of shock, Norton’s first concern was for his ship.
“Endeavour!” he called. “Situation report!”
“All OK, Skipper,” was the reassuring answer from the Exec. “We felt a slight tremor, but nothing that could cause any damage. There’s been a small change of attitude—the bridge says about point two degrees. They also think the spin rate has altered slightly—we’ll have an accurate reading on that in a couple of minutes.”
So it’s beginning to happen, Norton told himself, and a lot earlier than we expected; we’re still a long way from perihelion, and the logical time for an orbit change. But some kind of trim was undoubtedly taking place—and there might be more shocks to come.
Meanwhile, the effects of this first one were all too obvious, up there on the curving sheet of water which seemed perpetually falling from the sky. The wave was still about ten kilometres away, and stretched the full width of the Sea from northern to southern shore. Near the land, it was a foaming wall of white, but in deeper water it was a barely visible blue line, moving much faster than the breakers on either flank. The drag of the shoreward shallows was already bending it into a bow, with the central portion getting further and further ahead.
“Sergeant,” said Norton urgently. “This is your job. What can we do?”
Sergeant Barnes had brought the raft completely to rest and was studying the situation intently. Her expression, Norton was relieved to see, showed no trace of alarm—rather a certain zestful excitement, like a skilled athlete about to accept a challenge.
“I wish we had some soundings,” she said. “If we’re in deep water, there’s nothing to worry about.”
“Then we’re all right. We’re still four kilometres from shore.”
“I hope so, but I want to study the situation.”
She applied power again, and swung Resolution around until it was just under way, heading directly towards the approaching wave. Norton judged that the swiftly moving central portion would reach them in less than five minutes, but he could also see that it presented no serious danger. It was only a racing ripple a fraction of a metre high, and would scarcely rock the boat. The walls of foam lagging far behind it were the real menace.
Suddenly, in the very centre of the Sea, a line of breakers appeared. The wave had clearly hit a submerged wall, several kilometres in length, not far below the surface. At the same time the breakers on the two flanks collapsed, as they ran into deeper water.
Anti-slosh plates, Norton told himself. Exactly the same as in Endeavour’s own propellant tanks—but on a thousand-fold greater scale. There must be a complex pattern of them all around the Sea, to damp out any waves as quickly as possible. The only thing that matters now is: are we right on top of one?
Sergeant Barnes was one jump ahead of him. She brought Resolution to a full stop and threw out the anchor. It hit bottom at only five metres.
“Haul it up!” she called to her crewmates. “We’ve got to get away from here!”
Norton agreed heartily; but in which direction? The Sergeant was headed full speed towards the wave, which was now only five kilometres away. For the first time, he could hear the sound of its approach—a distant, unmistakable roar which he had never expected to hear inside Rama. Then it changed in intensity; the central portion was collapsing once more and the flanks were building up again.
He tried to estimate the distance between the submerged baffles, assuming that they were spaced at equal intervals. If he was right, there should be one more to come; if they could station the raft in the deep water between them, they would be perfectly safe.
Sergeant Barnes cut the motor, and threw out the anchor again. It went down thirty metres without hitting bottom.
“We’re OK,” she said, with a sigh of relief. “But I’ll keep the motor running.”
Now there were only the lagging walls of foam along the coast; out here in the central Sea it was calm again, apart from the inconspicuous blue ripple still speeding towards them. The Sergeant was just holding Resolution on course towards the disturbance, ready to pour on full power at a moment’s notice.
Then, only two kilometres ahead of them, the Sea started to foam once more. It humped up in white-maned fury, and now its roaring seemed to fill the world. Upon the sixteen-kilometre-high wave of the Cylindrical Sea, a smaller ripple was superimposed, like an avalanche thundering down a mountain slope. And that ripple was quite large enough to kill them.
Sergeant Barnes must have seen the expressions on the faces of her crewmates. She shouted above the roar: “What are you scared about? I’ve ridden bigger ones than this.” That was not quite true; nor did she add that her earlier experience had been in a well-built surfboat, not an improvised raft. “But if we have to jump, wait until I tell you. Check your lifejackets.”
She’s magnificent, thought the Commander—obviously enjoying every minute, like a Viking warrior going into battle. And she’s probably right—unless we’ve miscalculated badly.
The wave continued to rise, curving upwards and over. The slope above them probably exaggerated its height, but it looked enormous—an irresistible force of nature that would overwhelm everything in its path.
Then, within seconds, it collapsed, as if its foundations had been pulled out from underneath it. It was over the submerged barrier, in deep water again. When it reached them a minute later Resolution merely bounced up and down a few times before Sergeant Barnes swung the raft around and set off at top speed towards the north.
“Thanks, Ruby—that was splendid. But will we get home before it comes round for the second time?”
“Probably not; it will be back in about twenty minutes. But it will have lost all its strength then; we’ll scarcely notice it.”
Now that the wave had passed, they could relax and enjoy the voyage—though no one would be completely at ease until they were back on land. The disturbance had left the water swirling round in random eddies, and had also stirred up a most peculiar acidic smell—“like crushed ants”, as Jimmy aptly put it. Though unpleasant, the odour caused none of the attacks of seasickness that might have been expected; it was something so alien that human physiology could not respond to it.
A minute later, the wave front hit the next underwater barrier, as it climbed away from them and up the sky. This time, seen from the rear, the spectacle was unimpressive and the voyagers felt ashamed of their previous fears. They began to feel themselves masters of the Cylindrical Sea.