So Miss Ross, who was Major Holt's secretary and one of his most trusted assistants, had been giving information to one group of saboteurs all the while. She was the most dangerous security leak in the whole Platform project.
But her fiancé wasn't a captive. He was the head of that group of saboteurs. He'd made love to her and proposed to her merely to prepare her to supply the information he wanted. He needed only to write a sufficiently agonized note, or gasp tormented pleas on a telephone, to get what he wanted.
Incidentally, he still had all his fingers when Joe knocked him cold.
Sally had recognized him as the subject of a snapshot she'd once seen Miss Ross crying over. Miss Ross had hidden it hastily and told her it was someone she had once loved, now dead. And this inadvertent disclosure that Miss Ross was the security leak the Major had never had a clue to could only have come about through such confusion as Mike had instigated and Haney and the Chief and Joe had organized. But Joe learned those facts only later.
At the moment, there was still the Platform to be gotten aloft. And there was plenty of work to do. There were two small rips in the plating, caused by fragments of the exploded truck. There were some bullet holes. The Platform could resist small meteorites at forty–five miles a second, but a high–velocity small–arm projectile could puncture it. Those scars of battle had to be welded shut. The rest of the scaffolding had to come down and the rest of the rocket tubes had to be affixed. And there was cleaning up to be done.
These things occupied the shift that came on at the time of the multiple sabotage assaults. At first the work was ragged. But the policy of turning the Security men into news broadcasters worked well. After all, the Platform was a construction job and the men who worked on it were not softies. Most of them had seen men killed before. Before the shift was half over, a definite work rhythm was evident. Men had begun to take an even greater pride in the thing they had built, because it had been assailed and not destroyed. And the job was almost over.
Sally went back to her father's quarters, to try to sleep. Joe stayed in the Shed. His throat was painful enough so that he didn't want to go to bed until he was genuinely tired, and he was thoroughly wrought up.
Mike the midget had gone peacefully to sleep again, curled up in a corner of the outgoing screening room. His fellow midgets talked satisfiedly among themselves. Presently, to show their superiority to mere pitched battles, two of them brought out a miniature pack of cards and started a card game while they waited for a bus to take them back to Bootstrap.
The Chief's Indian associates loafed comfortably while waiting for the same busses. Later they would put in for overtime—and get it. Haney mourned that he had been remote from the scene of action, and was merely responsible for the presence and placing and firing of the machine guns that had certainly kept the Platform from being blown up from below.
It seemed that nothing else would happen to bother anybody. But there was one thing more.
That thing happened just two hours before it was time for the shift to change once again, and when normal work was back in progress in the Shed. Everything seemed fully organized and serene. Everything in the Shed had settled down, and nothing had happened outside.
There was ample exterior protection, of course, but the outside–guard system hadn't had anything to do for a very long time. Men at radar screens were bored and sleepy from sheer inactivity and silence. Pilots in jet planes two miles and five miles and eight miles high had long since grown weary of the splendid view below them. After all, one can get very used to late, slanting moonlight on cloud masses far underneath, and bright and hostile–seeming stars overhead.
So the thing was well timed.
A Canadian station noticed the pip on its radar screen first. The radar observer was puzzled by it. It could have been a meteor, and the Canadian observer at first thought it was. But it wasn't going quite fast enough, and it lasted too long. It was traveling six hundred seventy–two miles an hour, and it was headed due south at sixty thousand feet. The speed could have been within reason—provided it didn't stay constant. But it did. There was something traveling south at eleven miles a minute or better. A mile in five–plus seconds. It didn't slow. It didn't drop.
The Canadian radarman debated painfully. He stopped his companion from the reading of a magazine article about chinchilla breeding in the home. He showed him the pip, still headed south and almost at the limit of this radar instrument's range. They discussed the thing dubiously. They decided to report it.
They had a little trouble getting the call through. The night long–distance operators were sleepy. Because of the difficulty of making the call, the radarmen became obstinate and insisted on putting it through. They reported to Ottawa that some object flying at sixty thousand feet and six hundred seventy–two miles an hour was crossing Canada headed for the United States.
There was a further time loss. Somebody in authority had to be awakened, and somebody had to decide that a further report was justified. Then the trick had to be accomplished, and a sleepy man in a bathrobe and slippers listened and said sleepily, "Oh, of course you'll tell the Americans. It's only neighborly!" and padded back to his bed to go to sleep again. Then he waked up suddenly and began to sweat. He'd realized that this might be the beginning of atomic war. So he set phone bells to jangling furiously all over Canada, and jet planes began to boom in the darkness.
But there was only one object in the sky. Over the Dakotas it went higher. It went to seventy thousand feet, and then eighty. How this was managed is not completely known, because there are still some details of that flight that have never been completely explained. But certainly jatos flared briefly at some point, and the object reached ninety thousand feet where a jet motor would certainly be useless. And then, almost certainly, rockets flared once more and well south of the Dakotas it started down in a trajectory like that of an artillery shell, but with considerably higher speed than most artillery shells achieve.
It was at about this time that the siren in the Shed began its choppy, hiccoughing series of warm–up notes. The news from Canada arrived, as a matter of fact, some thirty seconds after the outer–perimeter radar screen around the Platform gave its warning. Then there was no hesitation or delay at all. Men were already tumbling out of bed at three airfields, buckling helmets and hoping their oxygen tanks would function properly. Then the radars atop the Shed itself picked up the moving speck. And small blue–white flames began to rise from the ground and go streaking away in the darkness in astonishing numbers.
The covers of the guns at the top of the Shed slid aside. Miles away, jet planes shot skyward, and newly wakened pilots looked at their night–fighting instruments and swore unbelievingly at the speed they were told the plunging object was making. The jet pilots gave their motors everything they could take, but it didn't look good.
The planes of the jet umbrella over the Shed stopped cruising and sprinted. And they were the only ones likely to get in front of the object in time.
Inside the Shed, the siren howled dismally and all the Security men were snapping: "Radar alarm! All out! Radar alarm! All out!"
And men were moving fast, too. Some came down from the Platform on hoists, dropping with reckless speed to the floor level. Some didn't wait for a turn at that. They slid down one upright, swung around the crosspiece on the level below, and slid down another vertical pipe. For a minute or more it looked as if the scaffolds oozed black droplets which slid down its pipes. But the drops were men. The floor became speckled and spotted with dots running for its exits.