Mandelbrot climbed up the ladder from the office to the top of the Compass Tower with Wolruf clinging to his back. They got through the trapdoor without incident. Then the robot began the long but simple task of descending the narrow line of footholds down the steep front face of the pyramid.

He almost certainly could have found his way down the labyrinth within the Compass Tower to the main entrance. However, he did not want to be questioned by security robots about his presence if he was found there. Derec had pointed out that if he was questioned about climbing down the outside of the Compass Tower, he would not have to reveal his knowledge of a secret entrance.

Derec had also told him of how he and Ariel had painstakingly climbed down these small hand and footholds when they had first arrived on the planet. They were only as large as a hand or foot might require, and the severe angle of the pyramid face offered little margin for error. For a robot, of course, the descent presented no significant challenge.

Mandelbrot spent the time of the descent considering how best to proceed. When they reached the ground, Wolruf let out a long sigh and collapsed in relief to the ground.

“Are you harmed?” Mandelbrot asked her.

“No.” The little alien shook her caninoid head back and forth. “Don’t like rride.”

Mandelbrot looked around. A number of humanoid robots were walking briskly on their way; among them, a much larger number of function robots, of all sizes and varied shapes, pursued their own duties. In spite of the unfamiliar architecture, this was basically the Robot City he remembered from his other visit here.

“What arr ‘u going to do now?” Wolruf inquired.

“I must take a calculated risk,” said Mandelbrot. In a space of time too quick for the alien even to notice, he made contact with the central computer and said, “I am a humanoid robot requesting duty assignment in the city matrix.”

“WHAT IS YOUR PRESENT ASSIGNMENT?”

“None.”

“WHAT WAS YOUR PREVIOUS ASSIGNMENT?”

“None.”

“YOU ARE IN ERROR. ALL ROBOTS IN ROBOT CITY HAVE BEEN ASSIGNED DUTIES. IF YOU HAVE RECENTLY BEEN RELEASED FROM A REPAIR FACILITY, YOU SHOULD GO THROUGH NORMAL REASSIGNMENT CHANNELS AT THAT FACILITY. “

“I have not been recently released from a repair facility. I am prepared to undertake duty assignment.”

“WHAT IS YOUR SERIAL NUMBER?”

Mandelbrot invented one that fit the pattern of other serial numbers he had noticed on his last visit.

“IT IS NOT ON FILE. ARE YOU A VISITOR TO ROBOT CITY?”

That was the question for which Mandelbrot was waiting. The way the computer responded to his answer might determine whether or not he would become a fugitive. “You should have me on record. I have past history on Robot City.” It was not a falsehood, but it was deliberately misleading. He didn’t add that he was on record by the names Alpha and Mandelbrot, not by the number he had just made up. The need to protect himself and his human companions allowed him to feel comfortable with the misdirection.

“YOUR NUMBER IS NOW ON FILE. YOU ARE NOW INCORPORATED INTO THE CITY MATRIX. YOU ARE ASSIGNED TO DUTY AT THE PRIORITY 4 REGIONAL CONTINGENCY POWER STATION. REPORT IMMEDIATELY.” The computer proceeded to give city coordinates for its location.

Mandelbrot waited to see if the computer would attempt a, shift in his programming, but it did not. No matter how paranoid Avery was, he had not programmed suspicion of unemployed robots into the central computer. Now Mandelbrot was relieved.

“I have been assigned a duty in the city matrix,” he said to Wolruf. “This will aid me in gathering information.” He was aware that the little alien had hardly had time to blink while he had conducted his exchange with the central computer.

“Wherr do we go?” She asked.

“We are going to Priority 4 Regional Contingency Power Station. This way.”

“What is it?” Wolruf asked as she ambled along beside him, gazing around at the sights.

“I surmise from its name that it supplies power to a limited portion of the city in the event of a failure in the main system. Priority 4 suggests a relatively important part of the city.”

“Long walk?”

“It is a greater distance than you would care to walk. However, I believe we will find a tunnel stop shortly along this street. Certainly one will be near the Compass Tower.”

Mandelbrot did not want to consult the central computer again so soon for anything he could learn himself. The current location of tunnel stops was an example. Every time he asked a question that a Robot City robot should already know, he would increase the chances of being investigated or even forcibly repaired.

They located a tunnel stop promptly, and rode down the moving ramp into the tunnel itself. Mandelbrot again placed Wolruf on his back, before stepping into the cramped platform booth. There was just enough room for both of them. He gave his destination to the console and let it figure out the nearest tunnel stop. Then they were off, riding the upright booth as it slid forward on the siding.

A moment later, the booth swung into one of the trunk lines with the other moving platforms. Humanoid robots rode with them on all sides, as motionless as Mandelbrot within their booths. The computer sped them up, slowed them down, and changed them from one parallel trunk line to another as the traffic flow changed as a result of some booths entering from sidings and others exiting onto them.

The booth they rode slowed smoothly, swung onto a siding, and glided to a stop. Mandelbrot stepped out and rode the ramp up to the street before setting Wolruf down again.

This area of the city was not noticeably different from the one they had just left. The city was too new to have old and new neighborhoods as such. It was highly organized, of course, but much of the pattern was not readily visible, such as the power grid or the tunnel system.

Mandelbrot oriented himself and led Wolruf to the power station. It was hardly more than a door in a very tall, narrow building wedged between others on three sides. Just as he entered, he used his comlink to report his assumed serial number, his name, and a request that communication be spoken aloud. In work stations of this kind, robots in Robot City often used their comlinks exclusively.

“I am the Station Supervisor,” said a humanoid robot inside the door. “My name is Tamserole. I was told to expect you, Mandelbrot. Why do you wish to speak aloud?”

“I have a personal preference for this.” Mandelbrot did not draw attention to Wolruf by looking at her or mentioning her. He knew she would listen carefully to any conversation. “What are my duties here?” He waited to see if Tamserole would require the use of comlinks.

“Come with me.” Tamserole had glanced at Wolruf, but apparently had no interest in her.

Mandelbrot and Wolruf followed Tamserole into the building. The inside was quite narrow and its single impressive feature was a pillar of shiny metal alloy, one meter thick, rising into the ceiling. A console of some kind was set into its base.

“Our task,” said Tamserole, “is to make this unit fully automated so that l-and now you, of course-may discontinue our duties here and accept our migration programming.”

Mandelbrot had no idea what migration programming was, but Tamserole obviously assumed he knew. At the moment, Mandelbrot did not dare reveal his ignorance.

“I do not understand why I have been given an assistant by the central computer, when I have been told to reduce staff here to zero, not to increase it,” said Tamserole. “Do you know why?”

“I believe so,” said Mandelbrot. “The central computer could not locate any past duty file on me. I think it decided to give me a redundant position until I prove my efficiency.”