And so young Bill Norton had found himself bowling along, at an exhilarating hundred kilometres an hour, while he furiously shovelled precious coal into the firebox of a locomotive that looked two hundred years old, but was actually younger than he was. The thirty-kilometre stretch of the Great Western Railway, however, was quite genuine, though it had required a good deal of excavating to get it back into commission.

Whistle screaming, they had plunged into a hillside and raced through a smoky, flame-lit darkness. An astonishingly long time later, they had burst out of the tunnel into a deep, perfectly straight cutting between steep grassy banks. The long-forgotten vista was almost identical with the one before him now.

“What is it, Skipper?” called Lt. Rodrigo. “Have you found something?”

As Norton dragged himself back to present reality, some of the oppression lifted from his mind. There was mystery here—yes; but it might not be beyond human understanding. He had learned a lesson, though it was not one that he could readily impart to others. At all costs, he must not let Rama overwhelm him. That way lay failure—perhaps even madness.

“No,” he answered, “there’s nothing down here. Haul me up—we’ll head straight to Paris.”

“I’ve called this meeting of the Committee,” said His Excellency the Ambassador of Mars to the United Planets, “because Dr. Perera has something important to tell us. He insists that we get in touch with Commander Norton right away, using the priority channel we’ve been able to establish after, I might say, a good deal of difficulty. Dr. Perera’s statement is rather technical, and before we come to it I think a summary of the present position might be in order; Dr. Price has prepared one. Oh yes—some apologies for absence. Sir Lewis Sands is unable to be with us because he’s chairing a conference, and Dr. Taylor asks to be excused…”

He was rather pleased about that last abstention. The anthropologist had rapidly lost interest in Rama, when it became obvious that it would present little scope for him. Like many others, he had been bitterly disappointed to find that the mobile worldlet was dead; now there would be no opportunity for sensational books and viddies about Raman rituals and behavioural patterns. Others might dig up skeletons and classify artifacts; that sort of thing did not appeal to Conrad Taylor. Perhaps the only discovery that would bring him back in a hurry would be some highly explicit works of art, like the notorious frescoes of Thera and Pompeii.

Thelma Price, the archaeologist, took exactly the opposite point of view. She preferred excavations and ruins uncluttered by inhabitants who might interfere with dispassionate, scientific studies. The bed of the Mediterranean had been ideal—at least until the city planners and landscape artists had started getting in the way. And Rama would have been perfect, except for the maddening detail that it was a hundred million kilometres away and she would never be able to visit it in person.

“As you all know,” she began, “Commander Norton has completed one traverse of almost thirty kilometres, without encountering any problems. He explored the curious trench shown on your maps as the Straight Valley; its purpose is still quite unknown, but it’s clearly important as it runs the full length of Rama—except for the break at the Cylindrical Sea—and there are two other identical structures 120 degrees apart round the circumference of the world.”

“Then the party turned left—or East, if we adopt the North Pole convention—until they reached Paris. As you’ll see from this photograph, taken by a telescope camera at the Hub, it’s a group of several hundred buildings, with wide streets between them.”

“Now these photographs were taken by Commander Norton’s group when they reached the site. If Paris is a city, it’s a very peculiar one. Note that none of the buildings have windows, or even doors! They are all plain rectangular structures, an identical thirty-five metres high. And they appear to have been extruded out of the ground—there are no seams or joints—look at this close-up of the base of a wall—there’s a smooth transition into the ground.”

“My own feeling is that this place is not a residential area, but a storage or supply depot. In support of that theory, look at this photo.”

“These narrow slots or grooves, about five centimetres wide, run along all the streets, and there’s one leading to every building—going straight into the wall. There’s a striking resemblance to the streetcar tracks of the early twentieth century; they are obviously part of some transport system.”

“We’ve never considered it necessary to have public transport direct to every house. It would be economically absurd—people can always walk a few hundred metres. But if these buildings are used for the storage of heavy materials, it would make sense.”

“May I ask a question?” said the Ambassador for Earth.

“Of course, Sir Robert.”

“Commander Norton couldn’t get into a single building?”

“No; when you listen to his report, you can tell he was quite frustrated. At one time he decided that the buildings could only be entered from underground; then he discovered the grooves of the transport system, and changed his mind.”

“Did he try to break in?”

“There was no way he could, without explosives or heavy tools. And he doesn’t want to do that until all other approaches have failed.”

“I have it!” Dennis Solomons suddenly interjected. “Cocooning!”

“I beg your pardon?”

“It’s a technique developed a couple of hundred years ago,” continued the science historian. “Another name for it is mothballing. When you have something you want to preserve, you seal it inside a plastic envelope, and then pump in an inert gas. The original use was to protect military equipment between wars; it was once applied to whole ships. It’s still widely used in museums that are short of storage space; no one knows what’s inside some of the hundred-year-old cocoons in the Smithsonian basement.”

Patience was not one of Carlisle Perera’s virtues; he was aching to drop his bombshell, and could restrain himself no longer.

“Please, Mr. Ambassador! This is all very interesting, but I feel my information is rather more urgent.”

“If there are no other points—very well, Dr. Perera.”

The exobiologist, unlike Conrad Taylor, had not found Rama a disappointment. It was true that he no longer expected to find life but sooner or later, he had been quite sure, some remains would be discovered of the creatures who had built this fantastic world. The exploration had barely begun, although the time available was horribly brief before Endeavour would be forced to escape from her present sun-grazing orbit.

But now, if his calculations were correct, Man’s contact with Rama would be even shorter than he had feared. For one detail had been overlooked—because it was so large that no one had noticed it before.

“According to our latest information,” Perera began, “one party is now on its way to the Cylindrical Sea, while Commander Norton has another group setting up a supply base at the foot of Stairway Alpha. When that’s established, he intends to have at least two exploratory missions operating at all times. In this way he hopes to use his limited manpower at maximum efficiency.”

“It’s a good plan, but there may be no time to carry it out. In fact, I would advise an immediate alert, and a preparation for total withdrawal at twelve hours’ notice. Let me explain…”

“It’s surprising how few people have commented on a rather obvious anomaly about Rama. It’s now well inside the orbit of Venus yet the interior is still frozen. But the temperature of an object in direct sunlight at this point is about five hundred degrees!”