lay one of the small Subterranean shoulder flyers. He gave Larkin a blank look.
"I don't know how to work the thing" he hissed.
"It's easy!" whispered Larkin. "Here!"
He pointed to a row of small buttons arranged on a metal strap that extended from the device. Bob had already observed on studying the flying warriors how the strap fitted. It was to fit across the left shoulder, down across the chest and under the right arm where it hooked firmly to the machine. Another strap ran from the right shoulder in the same fashion. The flyer fitted to the shoulders somewhat like a knapsack.
"These buttons control the thing, Allen," Larkin continued in whispers. "By pressing the topmost one, the one nearest to your throat, you start the propellers whirling. In rising you press the buttons from the top on down according to the speed you want. When descending you merely press them from the bottom up. This reverses the screw and lets you down slow and easy like. Now here's the taas tube, should you need it, old man"
He glanced anxiously at the guards. Leaning as they were against the thick walls at the door, they seemed dozing. He continued:
"This tube also has control buttons on it," he said. "Number one, that closest to the business end, projects the brillia-ray. Number two shoots the hideo-beam and here—this one will strip a man clean of his flesh! Each button releases a more powerful beam than the one ahead of it. When you want to shoot a man off the earth entirely, you press the last button. There won't be even a fragment left of the target if you hit it with the ray this button releases! So there you are, Skipper. The rest is up to you. All I can do is to start a fight and attract the guards from the door. The rest is up to you. Good luck, old man!"
WITH that Larkin rose to his feet, hunched his shoulders forward and stalked toward the far end of the long room. Bob grasped the flight motor and taas tube tensely, careful not to let his palm or fingers press down any of the control buttons on either. He saw the engineer halt abruptly in the center of the room. Larkin glared at his comrades for a few seconds and then Bob heard his voice rising above the buzz of conversation. He called for silence and got it with difficulty.
"Listen, you guys!" he roared. "You talk like a bunch of half-wits! You'll be wiped out if you try a break! You ought to know you ain't got a chance. The time's not ready yet. Now don't start anything. Something's gonna break for us soon and I'm warning you to wait. Hear that? Wait! Don't do anything! Just watch and wait! What I'm going to do now is for a reason. Get that? A good reason! I want Jimson, Craig and Barlow to step forward! Lively now!"
Bob saw three skeletons detach themselves from a group that lay close together at the far corner of the barracks. Scarcely had they started forward than Larkin hurled himself at them, snarling fiercely. They seemed taken aback by surprise. Larkin's right arm shot forward. Bob heard the sharp smack of flesh striking flesh. One of the skeletons toppled over backward.
"Fight, you guys!" Larkin snarled at them. "Fight! It’s for a reason! Come on!"
The two skeletons, sensing something of vital importance in the air, came toward Larkin eagerly now. Snarling and yelling curses, they went at it like hell-possessed demons. Instantly the four guards, seeing the commotion, rushed into the barracks, holding their taas tubes up like black-jacks.
Without waiting to see the results of the forced fight. Bob leaped to his feet, stepped over Dr. Marsden's silent form and slipped into the corridor, carrying his taas motor and tube. Nor did he pause near the door of the barracks. Instead he continued on until he encountered an abrupt turn in the tunnel. Here he paused and as if he had planned his movements to the second, he quickly slipped the motor straps over his shoulders and snapped the device into place on his back. It was so light in weight that he wondered suddenly if it had the power to cary him aloft when he would reach the open crater.
With his heart thudding against his ribs, he pressed the first button as Larkin had directed him. Instantly the small propellers began to spin. He felt them vibrating, giving him a peculiar feeling of buoyancy, lifting him to his toes. To test the device for his own satisfaction and safety, he gave a slight bound upward.
Instead of going up only a few inches, the machine lifted him almost to the roof of the glowing tunnel, letting him down again lightly. He was jubilant, knowing that with the additional power sent into it by the pressing of the remaining buttons, the machine would transport him into the air with perfect ease and rapidity. It made no sound beyond a low, almost inaudible hum of the radon motors incased within it.
Tensely gripping his taas tube, thumb placed lightly over the button that would release the weapon's most deadly ray, he went cautiously forward. As he went, he felt the machine grow warm against the bare flesh on his shoulder-blades. But he paid no attention to such trivials now. He was on his way at last to the crater's rim to learn what he might about Patti Marsden.
With utmost caution he proceeded along the corridor. The tunnel was a large one and went weaving snake-like toward the abyss. Others branched off occassionally and as he hugged the walls he passed a great room in which lolled a number of silent Subterraneans. His heart stood still when he encountered the door and it was a good minute before he continued on past it
Otherwise, the corridors seemed deserted. He heard no sound from the barracks he had left in a turmoil. But he craved darkness to hide him from the view of any alert Subterranean. There was only the blue glow that illuminated the underground world constantly. He proceeded carefully, tensely, in full view of any Inner World creature he might encounter.
But he was not afraid. All fear had long since left him. His eyes blazed with the determination to get to the crater edge at any cost. Three human skeletons lay up there. One of them might have held the flesh of Patti. He hoped to find the truth, perhaps in scattered fragments of clothing, perhaps by a more gruesome means—that of comparing the skeletons with one another and judging by the sizes. As a last resort he had resolved to count the ribs. Then if Patti had been killed by the murderous Subterraneans, well, he might settle a double score, before they assassinated him.
Silence beat down upon him like the roar of a Niagara as he continued onward. He was like a lion stalking a kill, his taas tube held in readiness, every nerve taut to
