In a flash of inspiration, he saw the open port of the dark closet-space at the rocket's tip. He climbed into it, swinging out from the ladder, hovering over the abyss, swinging his legs into the dark, padded interior. He crammed himself into it, found he fitted it neatly with very little room to spare and, grasping the circular door, pulled it toward him. It swung shut on its oiled hinges, clicked tightly into place. Robin crouched down, silent. For a while there was dead silence. Robin wondered if he would be able to hear anything that went on outside, considering the padding of the little space. For once he was thankful for being so short. If he'd been a few inches taller, he'd have found his position very uncomfortable. It was cramped, but not unbearable. He strained his ears, finally heard the vibrations of the jeep draw up to the base of the rocket and stop. He heard faint sounds which must have been the muffled voices of the jeep's riders. He lay quietly, hoping he would not be discovered. Outside, the jeep had come to a stop and the two men in the front seat stared around suspiciously. "I'd have sworn I saw a light for a moment out here," said the driver. The other scratched his head, looked around. "I'd better get out and look around, just to be certain." They both descended from the jeep. One went over and looked into the trucks and carriers, peering under them for possible hideaways. The other poked around the scaffolding at the base of the rocket. "This is the one they're firing off tomorrow, isn't it?" he asked when the other joined him after a moment. "Yeah," answered his companion, "or rather this morning. In fact in only a few hours. They've only got to load the main fuel chambers and they're ready." He shined his flashlight on the operations chart, the same one that Robin had examined earlier. "I wonder how come they loaded the other three earlier. That's odd. I thought that stuff couldn't hang around too long." "Don't you know," said the other, "this is that big top-secret experimental job they were working so fast on this week? Something to do with a new kind of fuel, fairly stable but loaded with radioactive elements. Some type of new compound which is supposed to add an atomic disintegration impetus when it goes off. Heard one of the engineers explain it as something like plutonium particles in suspension which get touched off atomically as they emerge in the rocket blast. They don't know for sure it will work." The other looked up at the towering structure. "I guess that's how come they're sending it up first with the regular loxygen fuel--so if the whole thing goes bang at once, it'll be high enough up not to blow the rest of us to kingdom come." He walked around the base a bit, stopped, flashed his light down, and picked up something. It was a cardboard sign that had been lying on the ground. He looked at it a moment. "Hey, this must have fallen from the cargo chamber," he said, showing his comrade the sign.