“But you think that they didn’t?” Regulo was rubbing at his scarred chin.
“I know they didn’t. The pod made it to the Moon, but they were dead when it got there.”
“So how did you find out all this?” Corrie was very close to Rob, reloading the spray injector. “And what about progeria? Where did you find that out? You’re not a biologist.”
“I had help, too.” Rob rubbed his right hand gingerly along his aching left forearm. The pain was increasing again, and Corrie could probably see it in his face. “I got most of this information from a source back on Earth. The thing I couldn’t find out there was the reason for the whole thing. To understand that, I had to return here.” He looked back to Regulo. “The Goblins were launched from Atlantis — an unauthorized launch, but one that was flagged in the system monitors. Then they died on the way to the Earth-Moon system. They ran into an acceleration too big for them to endure.”
“From a Mischener Drive ?” Regulo had begun to play with the control keys on the desk in front of him. He glanced up at Rob. “You know better than that. The Mischeners can’t go better than half a gee. Are you saying your Goblins can’t stand that much?”
“I don’t know what they can stand. But they were given about thirty or forty gee, enough to kill any of us. And they didn’t get it from the Mischeners.”
“From what, then? You know the regulations on drive accelerations. There’s not a thing in the System that can give forty gees.”
“That’s what I told Howard Anson.” Rob watched Regulo closely. He saw no reaction to Anson’s name. “But then I realized I was wrong. On my way out here from Earth I decided that there is a way to get that acceleration, one that doesn’t depend on tampering with a ship’s drive. And it’s one that would appeal to Darius Regulo more than anyone else.”
Rob looked up to the big display screen. Despite Regulo’s earlier words, Lutetia still loomed larger and larger.
“And what do you think appeals to Darius Regulo?” The quiet words interrupted Rob’s inspection of the display.
“You gave me a hint, last time I was here.” Rob’s tone was bitter. “I was just too stupid to see it. You gave me a lot of talk about matter transmitters, and the problem of transit times around the System. You had your method working even then. I should have realized what you were up to when you paid to use extra Spiders, and asked me to build the beanstalk instead of using Sala Keino. He was on your payroll, and he was your expert on space construction. But you had a better use for him.”
“No, Rob, don’t get that wrong.” Regulo’s voice showed an odd mixture of pride and reproof. “You are a better construction man than Keino will ever be. I picked you for the hard job, not the easy one. How far have you thought it through?”
That was a touch of the old Regulo. Rob wondered if his exhausted brain had jumped to a wrong conclusion about the old man. Well, a few more minutes and he could collapse.
“Just the general idea. It starts with the Spider again. Now it’s spinning a different kind of web. Rockets are wrong. That’s sitting there in your desk as we talk, but I didn’t follow it far enough. I should have known you wouldn’t stop with the beanstalk, that just gets us up and down from Earth. You wanted a way of moving materials around the whole System without using drives. And the Spider could give you that.”
Rob paused for a few seconds, to examine again his left forearm. The pain was mounting, from acute to intolerable. He checked once more that the power input was disconnected. No doubt about that. He massaged the arm again with his right hand, unable to imagine any possible explanation. He motioned to Corrie to use the injector a second time. What was the maximum permitted dose?
“Spin another cable,” he went on. “Make it like the beanstalk, with superconducting cables and drive train attached to the load cable. This time, put the powersat at the center of the cable, with an equal length on each side of it. Fabricate it in space, but don’t ever plan to fly it in and tether it. Leave it out near the orbit of Mars, or in the Belt, or in near Earth — key places in the System. Then start it rotating about its center, like a couple of spokes on a wheel. I assume that you began with just a couple of them, one in the Belt and one near Earth?”
Regulo nodded calmly. He had finished fiddling with the control panel and now seemed oddly relaxed. “We started with two. That’s just the beginning. The more you have, the better the efficiency of the whole operation. I’ve been thinking we’d build about five thousand of them through the Earth-Belt region.”
“You could handle that many?”
“With Sycorax? Easily. We can track that number, and more — there are millions of orbits in the data banks already. This is just a few extra ones.” Regulo’s tone was that of a patient teacher. “I’ve told you before, Rob,” he went on. “Think big. The System’s a big place. You have to scale your thinking to match it.”
Rob would normally have found the conversation totally fascinating. Now it felt increasingly surrealistic. Was Regulo on his own kind of tranquilizers? The image of Morel’s body had gone from the screen, and with it any interest by Regulo in Rob’s accusation. He seemed happy to talk engineering.
Apparently Corrie was having the same reaction. “Don’t you two have any feelings?” she broke in. “Joseph Morel is dead, Caliban seems to have gone mad, and you sit there talking about spinning beanstalks. What about the Goblins, Rob? First you tell us there are children in Morel’s lab. Then you start talking about something completely different.”
As she spoke she realized that she was not getting through to them. They both ignored her. Some invisible cord of tension bound them to each other, some other level of communication was taking place deep below the surface.
“So how would you work it, Rob?” said Regulo. His bright eyes were fixed on the other man’s pale face.
Rob hesitated, but the urge to explain was too strong.
“Just as you did. You have a rotating cable out in a free orbit — thousands of kilometers of it.” He leaned forward, at the same time as Regulo moved his chair farther away from the desk.
“Now suppose you want to move a space pod from the Belt to the Moon,” Rob went on. “You make it rendezvous with the center of the cable, where the powersat sits. The center of mass of the cable would be moving in a free-fall orbit, travelling about the sane speed as the pod, so you use hardly any reaction mass to make the rendezvous. You don’t need much acceleration from the pod’s drives, either, just a fraction of a gee will be enough. Once you have the pod at the middle of the cable, you let it move out along the drive train. As the pod moves from the center it feels a centripetal acceleration. You need to use the drive train on the cable to restrain it. When it reaches the end of the cable, you release it to move in free fall. You’ve given it a big velocity boost. But the trouble from the point of view of a human on the pod is the acceleration. Out at the end of the cable, it’s huge. I looked at a couple of examples. A cable four thousand kilometers long, with end velocity of twenty-four kilometers a second, would give thirty gees at each end. That’s what killed the Goblins.”
“They were unlucky.” Regulo had moved his chair farther and farther from the desk, until it was almost back to the wall. “If you like, you could even say that it was Caliban’s fault. He received no inputs on space operations for passenger transfer, and intelligence can’t replace experience. He put the space pod to a cable rendezvous with a cargo Slingshot — one with high accelerations, never intended for people.”