Rendezvous With Rama - Arthur C. Clarke [35]
Up there in the sky—or what the mind still persisted in calling the sky—something extraordinary was happening. At first, it seemed to Norton that the Sea was boiling. It was no longer static and frozen in the grip of an eternal winter; a huge area, kilometres across, was in turbulent movement. And it was changing colour; a broad band of white was marching across the ice.
Suddenly a slab perhaps a quarter of a kilometre on a side began to tilt upwards like an opening door. Slowly and majestically, it reared into the sky, glittering and sparkling in the beam of the searchlight. Then it slid back and vanished underneath the surface, while a tidal wave of foaming water raced outwards in all directions from its point of submergence.
Not until then did Commander Norton fully realize what was happening. The ice was breaking up. All these days and weeks, the Sea had been thawing, far down in the depths. It was hard to concentrate because of the crashing roar that still filled the world and echoed round the sky, but he tried to think of a reason for so dramatic a convulsion. When a frozen lake or river thawed on Earth, it was nothing like this . . .
But of course! It was obvious enough, now that it had happened. The Sea was thawing from beneath as the solar heat seeped through the hull of Rama. And when ice turns into water, it occupies less volume . . .
So the Sea had been sinking below the upper layer of ice, leaving it unsupported. Day by day the strain bad been building up; now the band of ice that encircled the equator of Rama was collapsing, like a bridge that had lost its central pier. It was splintering into hundreds of floating islands that would crash and jostle into each other until they too melted. Norton's blood ran suddenly cold, when he remembered the plans that were being made to reach New York by sledge . . .
The tumult was swiftly subsiding; a temporary stalemate had been reached in the war between ice and water. In a few hours, as the temperature continued to rise, the water would win and the last vestiges of ice would disappear. But in the long run, ice would be the victor, as Rama rounded the sun and set forth once more into the interstellar night.
Norton remembered to start breathing again; then he called the party nearest the Sea. To his relief, Lieutenant Rodrigo answered at once. No, the water hadn't reached them. No tidal wave had come sloshing over the edge of the cliff. 'So now we know,' he added very calmly, 'why there is a cliff.' Norton agreed silently; but that hardly explains, he thought to himself, why the cliff on the southern shore is ten times higher . . .
The Hub searchlight continued to scan round the world. The awakened Sea was steadily calming, and the boiling white foam no longer raced outwards from capsizing ice floes. In fifteen minutes, the main disturbance was over.
But Rama was no longer silent; it had awakened from its sleep, and ever and again there came the sound of grinding ice as one berg collided with another.
Spring had been a little late, Norton told himself, but winter had ended.
And there was that breeze again, stronger than ever. Rama had given him enough warnings; it was time to go.
As he neared the halfway mark, Commander Norton once again felt gratitude to the darkness that concealed the view above—and below. Though he knew that more than ten thousand steps still lay ahead of him, and could picture the steeply ascending curve in his mind's eye, the fact that he could see only a small portion of it made the prospect more bearable.
This was his second ascent, and he had learned from his mistakes on the first. The great temptation was to climb too quickly in this low gravity; every step was so easy that it was very hard to adopt a slow, plodding rhythm. But unless one did this, after the first few thousand steps strange aches developed in the thighs and calves. Muscles that one never knew existed