It was also quite monotonous, walking forward in the beam of the searchlight through the anechoic darkness of Rama. As the pool of light advanced with them, it slowly elongated into a long, narrow ellipse; this foreshortening of the beam was the only visible sign of progress. If the observers up on the Hub had not given them continual distance checks, they could not have guessed whether they had travelled one kilometre, or five, or ten. They just plodded onwards through the million-year-old night, over an apparently seamless metal surface.
But at last, far ahead at the limits of the now-weakening beam, there was something new. On a normal world it would have been a horizon; as they approached, they could see that the plain on which they were walking came to an abrupt stop. They were nearing the edge of the Sea.
“Only a hundred metres,” said Hub Control. “Better slow down.”
That was hardly necessary, yet they had already done so. It was a sheer straight drop of fifty metres from the level of the plain to that of the Sea—if it was a sea, and not another sheet of that mysterious crystalline material. Although Norton had impressed upon everyone the danger of taking anything for granted in Rama, few doubted that the Sea was really made of ice. But for what conceivable reason was the cliff on the southern shore five hundred metres high, instead of the fifty here?
It was as if they were approaching the edge of the world; their oval of light, cut off abruptly ahead of them, became shorter and shorter. But far out on the curved screen of the Sea their monstrous foreshortened shadows had appeared, magnifying and exaggerating every movement. Those shadows had been their companions every step of the way, as they marched down the beam, but now that they were broken at the edge of the cliff they no longer seemed part of them. They might have been creatures of the Cylindrical Sea, waiting to deal with any intruders into their domain.
Because they were now standing on the edge of a fifty-metre cliff, it was possible for the first time to appreciate the curvature of Rama. But no one had ever seen a frozen lake bent upwards into a cylindrical surface; that was distinctly unsettling, and the eye did its best to find some other interpretation. It seemed to Dr. Ernst, who had once made a study of visual illusions, that half the time she was really looking at a horizontally curving bay, not a surface that soared up into the sky. It required a deliberate effort of will to accept the fantastic truth.
Only in the line directly ahead, parallel to the axis of Rama, was normalcy preserved. In this direction alone was there agreement between vision and logic. Here—for the next few kilometres at least—Rama looked flat, and was flat… And out there, beyond their distorted shadows and the outer limit of the beam, lay the island that dominated the Cylindrical Sea.
“Hub Control,” Dr. Ernst radioed, “please aim your beam at New York.”
The night of Rama fell suddenly upon them, as the oval of light went sliding out to sea. Conscious of the now invisible cliff at their feet, they all stepped back a few metres. Then, as if by some magical stage transformation, the towers of New York sprang into view.
The resemblance to old-time Manhattan was only superficial; this star-born echo of Earth’s past possessed its own unique identity. The more Dr. Ernst stared at it, the more certain she became that it was not a city at all.
The real New York, like all of Man’s habitations, had never been finished; still less had it been designed. This place, however, had an overall symmetry and pattern, though one so complex that it eluded the mind. It had been conceived and planned by some controlling intelligence and then it had been completed, like a machine devised for some specific purpose. After that there was no possibility of growth or change.
The beam of the searchlight slowly tracked along those distant towers and domes and interlocked spheres and crisscrossed tubes. Sometimes there would be a brilliant reflection as some flat surface shot the light back towards them; the first time this happened, they were all taken by surprise. It was exactly as if, over there on that strange island, someone was signalling to them…
But there was nothing that they could see here that was not already shown in greater detail on photographs taken from the Hub. After a few minutes, they called for the light to return to them, and began to walk eastwards along the edge of the cliff. It had been plausibly theorized that, somewhere, there must surely be a flight of steps, or a ramp, leading down to the Sea. And one crewman, who was a keen sailor, had raised an interesting conjecture.
“Where there’s a sea,” Sergeant Ruby Barhes had predicted, “there must be docks and harbours—and ships. You can learn everything about a culture by studying the way it builds boats.” Her colleagues thought this a rather restricted point of view, but at least it was a stimulating one.
Dr. Ernst had almost given up the search, and was preparing to a descent by rope, when Lt. Rodrigo spotted the narrow stairway. It could easily have been overlooked in the shadowed darkness below the edge of the cliff, for there was no guardrail or other indication of its presence. And it seemed to lead nowhere; it ran down the fifty-metre vertical wall at a steep angle, and disappeared below the surface of the Sea.
They scanned the flight of steps with their helmet-lights, could see no conceivable hazard, and Dr. Ernst got Commander Norton’s permission to descend. A minute later, she was cautiously testing the surface of the Sea.
Her foot slithered almost frictionlessly back and forth. The material felt exactly like ice. It was ice.
When she struck it with her hammer, a familiar pattern of cracks radiated from the impact point, and she had no difficulty in collecting as many pieces as she wished. Some had already melted when she held up the sample holder to the light; the liquid appeared to be slightly turbid water, and she took a cautious sniff.
“Is that safe?” Rodrigo called down, with a trace of anxiety.
“Believe me, Boris,” she answered, “if there are any pathogens around here that have slipped through my detectors, our insurance policies lapsed a week ago.”
But Boris had a point. Despite all the tests that had been carried out, there was a very slight risk that this substance might be poisonous, or might carry some unknown disease. In normal circumstances, Dr. Ernst would not have taken even this minuscule chance. Now, however, time was short and the stakes were enormous. If it became necessary to quarantine Endeavour, that would be a very small price to pay for her cargo of knowledge.
“It’s water, but I wouldn’t care to drink it—it smells like an algae culture that’s gone bad. I can hardly wait to get it to the lab.”
“Is the ice safe to walk on?”
“Yes, solid as a rock.”
“Then we can get to New York.”
“Can we, Pieter? Have you ever tried to walk across four kilometres of ice?”
“Oh—I see what you mean. Just imagine what Stores would say, if we asked for a set of skates! Not that many of us would know how to use them, even if we had any aboard.”
“And there’s another problem,” put in Boris Rodrigo. “Do you realize that the temperature is already above freezing? Before long, that ice is going to melt. How many spacemen can swim four kilometres? Certainly not this one…”
Dr. Ernst rejoined them at the edge of the cliff, and held up the small sample bottle in triumph.
“It’s a long walk for a few cc’s of dirty water, but it may teach us more about Rama than anything we’ve found so far. Let’s head for home.”
They turned towards the distant lights of the Hub, moving with the gentle, loping strides which had proved the most comfortable means of walking under this reduced gravity. Often they looked back, drawn by the hidden enigma of the island out there in the centre of the frozen sea. And just once, Dr. Ernst thought she felt the faint suspicion of a breeze against her cheek. It did not come again, and she quickly forgot all about it.