As soon as he was on foot, he began looking for the right place to hole up while working on the suit. He did not need sunlight for what he had to do, since the augment had its own worklamps. A shadowed hollow, a darkened crevice, a pitch-black ice cave-any of those would hide him without hindering his efforts. But the better hidden he was, the less warning he would have about the approach of the robots or the raiders. There was no having it both ways.
While Derec hiked across the frozen terrain and equivocated, he used the augment’s omnidirectional radio to send a series of distress calls. Derec did not know if the signals would carry over the horizon to the raider, and he feared that they would lead the robots to him. But he had to try, had to give the raiders a chance and a reason to save him.
“Clear channel, code 1. To all ships: pilot marooned, requires pickup. Respond if in range. To all ships-”
Eventually Derec settled on a fissure in an ice cliff that faced back the way he had come. From there, he had a fair view of the terrain, except for what was blocked by the larger crags and mounds. And he had a clear view of the sky from the horizon on the northwest to the horizon on the northeast.
“Diagnostic library,” he said.
The lower half of the bubblelike viewport turned opaque and a list of subsystems appeared on it in bright yellow letters. He scanned down the list quickly.
“Motive systems.”
One of the items near the middle of the list flashed twice, and then the entire list was replaced by another. In the same manner, Derec worked his way through the help screens until the circuit and logic paths of the subcontroller filled the half-display with a maze of fine tracings. Derec studied the system carefully, his lips pursed into a frown.
“Frost,” he muttered finally.
It was as he had feared. The governor was not a physical device that could be readily disconnected. It was a feedback loop in the leg servo circuits. The loop told the suit controller, “Do not allow the force applied by the drivers to exceed a force ofx number of dynes persecond.” Small forces applied quickly were acceptable, as were large forces applied slowly. But large forces applied quickly, which was what he needed, were forbidden.
If he had had more time, there might have been a chance to reprogram the subcontrollers. But under the circumstances, it would have to be radical surgery. Fortunately, augments were designed to be field-repairable, a practice which had saved more than one laborer’s life.
The various “hands” which the augment could use were located in bulging closures on the suit’s thighs. Derec selected an illuminated micromanipulator for the right, and a spotweld laser for the left.
Just then the ground under and around him shook suddenly, bringing a minor avalanche of slow-falling particles down on the crown of the suit. “Clear,” he ordered. The bubble became a window again, revealing to Derec a chilling sight. The attacking spacecraft had climbed above the western horizon. It was still firing randomly, still carving out a path of destruction on the asteroid’s surface. Time was running out.
“Shut down subsystem twenty-four.” That was it: he was committed. With the leg controllers powered down, Derec could no longer walk.
The modifications included burning through three circuit traces and fusing a fourth to a neighboring circuit as a shunt. Accuracy with the tiny laser was absolutely critical. A misfire could destroy enough circuits to cripple the augment permanently.
With the help of the augment’s pointing guide, Derec completed the work on the right leg without mishap. But by the time he was ready to start on the left, the vibrations from the more powerful explosions were more than strong enough to disturb his aim. As he stood trying to outguess the shaking ground, a familiar voice intruded:
“Derec, please listen. Derec, you must stop. This is madness-”
Two hundred meters away on the slope of the mound due north of him was a robot. It was Monitor 5, waving its arms and advancing directly toward where Derec stood. It was walking easily, with no sign of the damage Derec had inflicted on its leg.
In the same glance, Derec saw that the reason the shaking was stronger was that the raider ship was much closer, more nearly overhead than he had expected. Once again he was trapped between the raiders, who would rescue him by killing him, and the robots, who would kill him by rescuing him.
“Go away!” Derec hissed.
“Derec, you must return to the compound. You are in danger here.”
The raider ship seemed to have taken notice of the robot, for the plain between Monitor 5 and the cliff where Derec stood suddenly came under a barrage of pinpoint laser impacts.
These were not the high-intensity weapons which were shaking the ground, and mercifully, the gunners did not seem to be targeting Derec. But the surface in this area was nearly all ice, and volatile. One blast boiled away the top of the mound behind the robot. Another gouged a deep trench between the robot and Derec.
Derec did not think that would stop Monitor 5, and he was right. The robot scrambled down into the trench before the billow of gas could even dissipate, and Derec lost sight of it.
He could not afford to worry about the robot. Setting his jaw determinedly, Derec went back to work on the left subcontroller. Using the body rigidity and autocontrol of the augment to the fullest, he made short work of it. The three unwanted circuits vaporized in tiny puffs of atomic metal. The two parallel traces melted and merged into one.
“Derec!” Monitor 5 called suddenly. “It’s here! In the ice! I’ve found it!”
Derec looked up. The firing had stopped, and there was no sign of the robot. “Close the panels,” he said, then tongued the radio switch. “Monitor 5, go back to the installation. There’s nothing you can do for me out here.”
Just then, a metallic arm appeared above the lip of the trench, the hand clutching a small silver object. A moment later Monitor 5 struggled out of the trench. Starting toward Derec, Monitor 5 raised the silver object triumphantly overhead in one hand.
“The key is here, Derec. You must take it-”
The robot’s triumph did not last long. The raider ship was now a great ominous mass directly overhead. Monitor 5 had barely taken a step when the laser fire started up again. Red targeting beams danced like spotlights on a stage on the ice around it.
For a moment it seemed as though the robot was going to escape destruction. Then, a dozen strides from the foot of the cliff, a laser tracked a fiery line across the robot’s torso. An instant later, Monitor 5 disappeared in a silent explosion, all blue-green flame and disintegrating metal.
Disappeared-but not completely. The explosion sent pieces flying in all directions. One of the largest, spinning so rapidly Derec could not tell what it was, came cartwheeling toward him. As it struck the ground and skidded to a stop, Derec saw what it was: Monitor 5’s right arm, from the shoulder joint to the fingers.
And still gripped tightly in those fingers was the shining silver object-a rectangle perhaps five centimeters by fifteen centimeters, the size of a remote controller or a memory cartridge.
Could this be the object that the robots were so obsessively searching for all this time? If so, then why had Monitor 5’s last act been to try to give it to Derec?
For a moment Derec hesitated. To retrieve the object was an additional risk in an enterprise which was already too risky. But he knew that it was impossible for him to simply leave it lying there. Ripping the specialized end effectors from the augment’s arms, Derec slapped the general-purpose grapples back in place.
“Power up system twenty-four,” he snapped, and the sole red lamp on the augment’s status board turned to green.