The navy sent over a small man named Shrenkly, who brought a large case of records. He was head of the code department, and a cipher and puzzle enthusiast as well. This was the greatest challenge of his long and undistinguished career. He hurled himself into the work with growing enthusiasm.
"Wonderful opportunity, wonderful. The ascending and descending series are going out steadily. In the meantime I am taping permutations and substitutions of signals which will—"
"That's fine, keep at it," Jason said, smiling enthusiastically and patting the man on the back. "I'll get a report from you later, but right now we have a meeting to attend. Kerk, Meta, time to go."
"What meeting?" Meta asked as he tried to get her through the door.
"The meeting I just made up to get away from that monomaniacal enthusiast," he said when he finally got her into the corridor. "Let him do his job while we see if we can find another way in."
"I think what he has to say is very interesting."
"Fine, you talk to him — but not while I am around. Let us now spur our brains into action and see what we can come up with."
What they came up with was a number of ideas of varying quality but uniform record of failure. There was the miniature-flying-robot fiasco, where smaller and smaller robots were sent and blasted out of existence, right down to the smallest, about the size of a small coin. Obsessed by miniaturization, they constructed a flying-eye apparatus no larger than the head of a pin. It dragged a threadlike control wire after it that also supplied current for the infinitesimal ion drive. This device sparked and sizzled its way to within fifteen kilometers of the Indestructible before the sensors detected it and neatly blasted it out of existence with a single shot.
There were other suggestions and brilliant plans, but none of them worked out in practice. The great ship floated serenely in space, reading seven hundred numbers a second and, in its spare time, blowing into fine dust any object that approached it. Each attempt took time; the days drifted by steadily. Jason was beginning to have a chronic headache and had difficulty sleeping. The problem seemed insoluble. He was feeding figures about destruction distances into the computer when Meta looked in on him.
"I'll be with Shrenkly if you need me," she said.
"Wonderful news."
"He taught me about frequency tables yesterday, and today he is going to start me on simple substitution ciphers."
"How thrilling."
"Well, it is to me. I've never done anything like this before. And it has some value: we are sending signals and one of them could be the correct one. It certainly is accomplishing more than you are with all your flying rocks. And there are only two days to go, too."
She stalked out and slammed the door. Jason slumped with fatigue, aware that failure was hovering close. He was pouring himself a huge glass of Old Fatigue Killer when Kerk came in.
"Two days to go," Kerk said.
"Thanks. I wouldn't have known if you hadn't told me. I am well aware that a Pyrran never gives up, but I am getting the sneaking suspicion that we are licked."
"We are not beaten yet. We can fight."
"A very Pyrran answer — but it won't work this time. We just can't barge in there in battle armor and shoot the place up."
"Why not? Small-arms fire would just bounce off of us — as well as the low-powered rays. All we have to do is dodge the big stuff and bull through."
"That's all! Do you have any idea how we are going to arrange that?"
"No. But you will figure something out. And you better hurry."
"I know, two days. I suppose it's easier to die than admit failure. We suit up, fly at the battleship behind a fleet of rocks that are blasted by the heavy stuff. Then we tell the enemy discrimination circuits that we are not armored space suits at all, but just a couple of jettisoned plastic beer barrels that they can shoot up with the small caliber stuff. Which then bounces off us like hail and we land inside and get a billion credits and live happily ever after."
"That's the sort of thing. I'll go and get the suits ready."
"Before you do that, just consider one thing in this preposterous plan. How do we tell the discrimination circuitry. " Jason's voice ran down in mid sentence, and his eyes opened wide — then he clapped Kerk on the back. Heavily too, he was so excited, but the Pyrran seemed completely unaware of the blow.
"That's it, that's how we do it!" Jason chortled, rushing to the computer console. Kerk waited patiently while Jason fed in figures and muttered over the pages of information that poured from the printer. The answer was not long in coming.
"Here it is!" Jason held up a sheet. "The plan of attack— and it's going to work. It is just a matter of remembering that the computer on that battleship is just a big dumb answering machine that counts on its fingers. But it does it very fast. It always performs in the same manner because it is programmed to do so. So here is what happens. Because of the main drive tubes the area with the least concentration of fire power is dead astern. Only one hundred and fourteen gun turrets can be trained that way. Their slew time varies."
"Slew time?"
"The time it takes a turret to rotate one hundred and eighty degrees in azimuth. The small ones do it in less than a second. This is one factor. Other factors are which targets get that attention. Fastest-moving rocks get blasted first, even if they are farther away than a larger, slower-moving target. There are other factors like rate of fire, angle of depression of guns, and so forth. Our computer has chomped everything up and come up with this!"
"What does it reveal?"
"That we can make it. We will be in the center of a disk of flying rocks that will be aimed at the rear of the Indestructible. There will be a lot of rock, enough to keep all the guns busy that can bear on the spot. Our suits will be half the size of the smallest boulder. We will all be going at the same speed, in the same direction, so we should get the small-caliber stuff. Now, another cloud of rock, real heavy stuff, will converge on the stern of the ship from a ninety-degree angle, but it will not hit the two-hundred-kilometer limit until after the guns start blasting at us. The computer will track it and as soon as our wave is blasted will slew the big guns to get rid of the heavy stuff. As soon as these fire, we accelerate toward the stern tubes. We will then become prime targets, but, before the big guns can slew back, we should be inside the tubes."
"It sounds possible. What is the time gap between the instant we reach the tubes and the earliest the guns can fire?"
"We leave their cone of fire exactly six-tenths of a second before they can blast us."
"Plenty of time. Let us go."
Jason held up his hand. "Just one thing. I'm game if you are. We carry cutting equipment and weapons. Once inside the ship there should not be too many problems. But it is not going to be that easy. I say that the two of us go. If we don't tell Meta she will stay here."
"Three have a better chance than two to get through."
"And two have a better chance than one. I'm not going unless you agree."
"Agreed. Set the plan up."
Meta was busy with her newfound interest in codes and ciphers; it was a perfect time. The Earth navy ships were well trained in precision rock-throwing — as well as being completely bored by it. They let the computers do most of the work. While the preparations were being made, Kerk and Jason suited up in the combat suits: more tanks than suits, heavy with armor and slung about with weapons. Kerk attached the special equipment they would need while Jason short-circuited the airlock indicator so that Meta, in the control room, would not know they had left the ship. Silently they slipped out.