Then they saw that it was not alone. Swimming round it, and snapping at its feebly moving limbs, were two small beasts like overgrown lobsters. They were efficiently chopping up the monster, and it did nothing to resist, though its own claws seemed quite capable of dealing with the attackers.

Once again, Jimmy was reminded of the crab that had demolished Dragonfly. He watched intently as the one-sided conflict continued, and quickly confirmed his impression.

“Look, Skipper,” he whispered. “Do you see—they’re not eating it. They don’t even have any mouths. They’re simply chopping it to pieces. That’s exactly what happened to Dragonfly.”

“You’re right. They’re dismantling it—like—like a broken machine.” Norton wrinkled his nose. “But no dead machine ever smelled like that!”

Then another thought struck him.

“My God—suppose they start on us! Ruby, get us back to shore as quickly as you can!”

Resolution surged forward with reckless disregard for the life of her power cells. Behind them, the nine spokes of the great starfish—they could think of no better name for it—were clipped steadily shorter, and presently the weird tableau sank back into the depths of the Sea.

There was no pursuit, but they did not breathe comfortably again until Resolution had drawn up to the landing stage and they had stepped thankfully ashore. As he looked back across that mysterious and now suddenly sinister band of water, Commander Norton grimly determined that no one would ever sail it again. There were too many unknowns, too many dangers…

He looked back upon the towers and ramparts of New York, and the dark cliff of the continent beyond. They were safe now from inquisitive man.

He would not tempt the gods of Rama again.

From now on, Norton had decreed, there would always be at least three people at Camp Alpha, and one of them would always be awake. In addition, all exploring parties would follow the same routine. Potentially dangerous creatures were on the move inside Rama, and though none had shown active hostility, a prudent commander would take no chances.

As an extra safeguard, there was always an observer up on the Hub, keeping watch through a powerful telescope. From this vantage point, the whole interior of Rama could be surveyed, and even the South Pole appeared only a few hundred metres away. The territory round any group of explorers was to be kept under regular observation; in this way, it was hoped to eliminate any possibility of surprise. It was a good plan—and it failed completely.

After the last meal of the day, and just before the 22.00 hour sleep period, Norton, Rodrigo, Calvert and Laura Ernst were watching the regular evening news telecast specially beamed to them from the transmitter at Inferno, Mercury. They had been particularly interested in seeing Jimmy’s film of the Southern continent, and the return across the Cylindrical Sea—an episode which had excited all viewers. Scientists, news commentators, and members of the Rama Committee had given their opinions, most of them contradictory. No one could agree whether the crablike creature Jimmy had encountered was an animal, a machine, a genuine Raman—or something that fitted none of these categories.

They had just watched, with a distinctly queasy feeling, the giant starfish being demolished by its predators when they discovered that they were no longer alone. There was an intruder in the camp.

Laura Ernst noticed it first. She froze in sudden shock, then said: “Don’t move, Bill. Now look slowly to the right.”

Norton turned his head. Ten metres away was a slender-legged tripod surmounted by a spherical body no larger than a football. Set around the body were three large, expressionless eyes, apparently giving 360 degrees of vision, and trailing beneath it were three whiplike tendrils. The creature was not quite as tall as a man, and looked far too fragile to be dangerous, but that did not excuse their carelessness in letting it sneak up on them unawares. It reminded Norton of nothing so much as a three-legged spider, or daddy-long-legs, and he wondered how it had solved the problem—never challenged by any creature on Earth—of tripedal locomotion.

“What do you make of it, Doc?” he whispered, turning off the voice of the TV newscaster.

“Usual Raman three-fold symmetry. I don’t see how it could hurt us, though those whips might be unpleasant—and they could be poisonous, like a coelenterate’s. Sit tight and see what it does.”

After regarding them impassively for several minutes, the creature suddenly moved—and now they could understand why they had failed to observe its arrival. It was fast, and it covered the ground with such an extraordinary spinning motion that the human eye and mind had real difficulty in following it.

As far as Norton could judge—and only a high-speed camera could settle the matter—each leg in turn acted as a pivot around which the creature whirled its body. And he was not sure, but it also seemed to him that every few “steps” it reversed its direction of spin, while the three whips flickered over the ground like lightning as it moved. Its top speed—though this also was very hard to estimate—was at least thirty kilometres an hour.

It swept swiftly round the camp, examining every item of equipment, delicately touching the improvised beds and chairs and tables, communication gear, food containers, Electrosans, cameras, water tanks, tools—there seemed to be nothing that it ignored, except the four watchers. Clearly, it was intelligent enough to draw a distinction between humans and their inanimate property; its actions gave the unmistakable impression of an extremely methodical curiosity or inquisitiveness.

“I wish I could examine it!” Laura exclaimed in frustration, as the creature continued its swift pirouette. “Shall we try to catch it?”

“How?” Calvert asked, reasonably enough.

“You know—the way primitive hunters bring down fast-moving animals with a couple of weights whirling around at the end of a rope. It doesn’t even hurt them.”

“That I doubt,” said Norton. “But even if it worked, we can’t risk it. We don’t know how intelligent this creature is—and a trick like that could easily break its legs. Then we would be in real trouble—from Rama, Earth and everyone else.”

“But I’ve got to have a specimen!”

“You may have to be content with Jimmy’s flower—unless one of these creatures cooperates with you. Force is out. How would you like it if something landed on Earth and decided that you would make a nice specimen for dissection?”

“I don’t want to dissect it,” said Laura, not at all convincingly. “I only want to examine it.”

“Well, alien visitors might have the same attitude towards you, but you could have a very uncomfortable time before you believed them. We must make no move that could possibly be regarded as threatening.”

He was quoting from Ship’s Orders, of course, and Laura knew it. The claims of science had a lower priority than those of space diplomacy.

In fact, there was no need to bring in such elevated considerations; it was merely a matter of good manners. They were all visitors here, and had never even asked permission to come inside…

The creature seemed to have finished its inspection. It made one more high speed circuit of the camp, then shot off at a tangent towards the stairway.

“I wonder how it’s going to manage the steps?” Laura mused. Her question was quickly answered; the spider ignored them completely, and headed up the gently sloping curve of the ramp without slackening its speed.

“Hub Control,” said Norton. “You may have a visitor shortly; take a look at the Alpha Stairway Section Six. And incidentally, thanks a lot for keeping such a good watch on us.”

It took a minute for the sarcasm to sink in; then the Hub observer started to make apologetic noises.