Burke said, "We'll have to use tools to get it open."
"Somebody made it," said Keller, "just before the garrison went away. They made it here!"
"Quite likely," agreed Burke. "We'll get at it presently. Now listen, Keller! I came along because a message might be useful. I think Holmes has found out something, though what it may be I can't guess. Come along with me. There've been developments and I want to hold a council of war. And I think I do mean war!"
He led the way back toward the ship. When they arrived, Holmes was awake and growling because of Burke's absence.
"You win," he told Burke. "I had a dream, and it wasn't a dream. I know something about those metal globes. They've got drives in them, and they can accelerate to a hundred and sixty gees, and I don't think I'll ride one."
Wryly, he told Burke what he'd experienced.
"I'm not too much surprised," said Burke. "I've managed two cube–experiences myself. I figure that these cubes trained men to operate things, without training their brains in anything else. They'd make illiterates into skilled men in a particular line, so anybody could do the work a highly trained man would otherwise be needed for. In one of my two cube–dreams I was a gun–pointer on one of those machines up on the third level. In the second cube–dream I was a rocket–pilot."
"No rockets in my cube," protested Holmes.
"Different period," said Burke. "Maybe, anyhow. In my dream we were using rockets to fight with, and the war was close. The enemy had taken some planets off Kandu—wherever that is!—and the situation was bad. We went out of here in rockets and fought all over the sky. But then there were supplies coming from home, and fresh fighting men turning up." He stopped abruptly. "How'd they come? I don't know. But I know they didn't come in spaceships. They just came, and they were new men and we veterans patronized them. The devil! Holmes, you say the globes have a hundred–sixty–gee drive! Nobody'd use rockets if drives like that were known!"
"To stay in the party," Sandy said suddenly, with something like defiance, "I tried a cube, too. And I was a sort of supply–officer. I had the experience of being responsible for supply and being short of everything and improvising this and that and the other to keep things up to fighting standard. It wasn't easy. The men grumbled, and we lacked everything. There was no fighting in my time, and there hadn't been for centuries. But we knew the Enemy hadn't given up and we had to be ready, generation after generation, even when nothing happened. And we knew that any minute the Enemy might throw something unexpected, some new weapon, at us."
"History–cubes," said Keller interestedly. "Different periods. Right?"
"Dammit, yes!" said Burke. "We've got accounts of past times and finished battles, but we need to know who's coming and what to do about it! Maybe the rocket–dream was earliest in time. But how could a race with nothing better than rockets ever get here? And how could they supply the building of a place like this?"
There was no answer. Facts ought to fit together. When they don't, they are useless.
"We've got snatches of information," said Burke. "But we don't know who built this fort, or why, except that there was a war that lasted thousands of years, with pauses for centuries between battles." He waved a hand irritably. "The Enemy tries to think up new weapons. They do. They try them. So far, they've been countered. But we're not prepared to fight a new weapon. Maybe the fort is set to battle old ones, but we don't know how to use it even for that! We've got to—"
"I think—" began Keller.
"I'd give plenty for a service manual on the probably useless weapons we do have," said Burke angrily. "Incidentally, Keller just found what may be an explanation of how and why this place was abandoned."
Keller said suddenly, "Where would service manuals be?"
He moved, almost running, toward the air–lock. Burke started to swear, and stopped.
"A service–and–repair manual," he snapped, "would be near the equipment it described. How many little shelves with boxes on them have we seen? They're just the right size to hold cubes! And where are they? Next to those fighting machines next to the door of the room where the ten–foot globes are! There's a shelf of them in the instrument–room! Let's find out how to fight with this misbegotten shell of a space–fort! There'll be no help coming to us, but if the Enemy's held off for thousands of years while this civilization fell apart, we might as well try to hold it together for a few minutes or seconds longer! Let's go get some real instruction–cubes!"
Keller was already gone. The others followed. Once they saw Keller in the far, far distance, hastening toward the instrument–room. Behind him, after almost running down the long corridor, Burke swung into the room where hundreds of ten–foot metal globes waited for the fortress to be remanned and to go into action again. Inside the door he found the remembered shelf, with two small boxes fastened to it. He pulled down one box and opened it. There was a black cube inside it. He thrust it upon Holmes.
"Here!" he said feverishly. "Find out how those globes work! Find out what's in them, how they drive!"
He ran. To the end of the corridor and up the ramp and past the supposed bunk–rooms and mess–halls. Up to the level where the ugly metal machines stood, each in its separate cubicle. There were little shelves inside each door. Each shelf contained a single box. Burke took one, two, and then stopped short.
"They'll be practically alike," he muttered. "No need."
He put one back. And then he felt almost insanely angry. One would need at least to be able to doze, to make use of the detailed, vivid, and utterly convincing material contained in the black cubes. And how could any man doze or sleep for the purpose of learning such desperately needed data? He'd need almost not to want the information to be able to sleep to get it!
Sandy and Pam overtook him as he stood in harried frustration with a black cube in his hands.
"Listen to me, Joe," said Sandy. "We've all taken chances, but if you get recurrent dreams from every cube you doze near—"
"When that happened to me," snapped Burke, "I was eleven years old and had one moment only. And that dream wasn't affected by the others in the cubes that came after it. And anyhow, no matter what happens to Holmes and me, we have to get these things ready for use! I don't know what we'll use them against. I don't know whether they'll be any use at all. But I've got to try to use them, so I've got to try to find out how!"
Sandy opened her mouth to speak again.
"I'm going off to fret myself to sleep," added Burke. "Holmes will be trying it too. And Keller."
"I don't think it's necessary," said Sandy.
"Why?"
"You found a sort of library of cubes. How useful would they be if one had to doze off to read them? How handy would a manual about repairing a weapon be, if somebody had to take a nap to get instructions? It wouldn't make sense!"
"Go on!" said Burke impatiently.
"Why not look in the library?" asked Sandy. "As a quartermaster officer, I think I knew that there was a reading–device for the cubes, like a projector for microfilm. It might have been taken away, but also—"
"Come along!" snapped Burke. "If that's so, it's everything! And it ought to be so!"
They hastened to the vast, low–ceilinged room which was filled with racks of black cubes. They were stacked in their places. At the far corner they found a desk and a cabinet. In the cabinet they found two objects like metal skull–caps, with clamps atop them. A cube would fit between the clamps. Burke feverishly sat a cube in position and put the skull–cap on his head. His expression was strange. After an instant he took it off and reversed the cube. He put it on. His face cleared. He lifted it off.