Their problem was really bugging the place more thoroughly than any place had ever been bugged while still preventing the bugs from being discovered by one who, although quite mad, was one of the sharpest security chiefs ever to walk out of the mine schools.

If they did this well, they would have a total record of the technology of

teleportation and its mathematics. They would know what happened to Psychlo because they would be able to cast out picto-recorders. They would know the whereabouts and possibly the intentions of other races. They would be in communication with the stars and universes and could defend themselves on Earth.

Terl would have to work out and build from scratch a whole transshipment console, for the one out there near the old platform was a burned-out ruin.

They needed devices that could read over his shoulder every book he opened, every page of figures he made. They needed to fix up his workroom in his office and rig it so that every resistor he picked up, every wire he put in, would be recorded exactly.

It was certain that he would sweep the place with a probe before every work period and possibly after every day of toil. He would be meticulous in his bug detection.

If Terl had any inkling the technology would be observed he would not start. If he thought it had been taken away by an alien, he would commit suicide. For there was no doubt that Terl had in his skull both the devices they had found in the dead Psychlos.

Before they had left Africa, Dr. MacKendrick had been very pessimistic about being able to remove such brain devices from all that bone and still have a live, functioning Psychlo on his hands. That chance was not entirely gone. But it was nothing to be counted on.

Angus had lately begun to understand why Jonnie had kept Terl alive, why they didn't just get out some battle planes and wipe this new political mess out. It was a very delicate situation. It was a thin chance. It had to work. But with what risks! Angus had no doubt whatever that Jonnie was holding his own life at stake. A huge and dangerous risk. But what a prize! The Psychlo technology of teleportation. Earth depended upon it.

Jonnie was a cool one, Angus thought. He himself would never have that much patience or be able to retain that detached an overview of the entire scene without permitting personal considerations from entering in.

Angus looked up from the locks. He was in awe of Jonnie as he thought about what they were doing. These people or Terl would kill Jonnie in a flash if they found him or knew what he was up to. Robert the Fox had denounced it as folly and a hopeless, unwarranted risk. Angus didn't think so. It was a brand of courage he had never seen before.

He got the cabinets opened. They contained all the paraphernalia a security chief ever thought he would need. They contained papers and records Terl would consider vital.

Jonnie was looking for superconfidential notes on teleportation or its odd mathematics. On his inspection he did not find anything on those subjects beyond normal tests. But he did find an item of interest.

It was a record of all the mineral deposits left on Earth. The company had not made a mineral survey for itself for centuries, content with their originals. But Terl had.

Jonnie smiled. There were sixteen lodes of gold on the planet almost as good as the one they had mined! In the Andes and the Himalayas– they just weren't that close to home and it would have been more public to have mined them. Ah, yes. All these other lodes were also associated with uranium.

There were thick records of Earth's existing mineral resources. Hundreds of years of security chiefs had continued to log the findings of the drones, which were used for security but were essentially mineral spotters.

The company, with its "semicore" methods of mining, could go down almost to the molten core, to the very bottom of the crust without breaking through. And they were content to mine what they had and conserve their assets of unmined wealth.

Terl had simply removed the records from company view for his own purposes.

Ores, metals! The planet was still wealthy in resources.

Jonnie recorded every page rapidly. This was not what he was here for, but it was nice to know their planet had not been bankrupted of minerals. They would need them.

Angus had found what they were really looking for just now-Terl's bug probe. It was an oblong box with an aerial sticking out of it and a disc cup on the tip of the aerial. It had on/off switches for various frequencies and light domes and buzzers.

Jonnie had done his apprenticeship well in the electronics shop. He knew that no wave this could detect would pass through lead or a lead alloy. Ordinarily this would not be a factor since any bug of any kind whatsoever would also not pass through lead. Therefore, why detect it since it wouldn't work as a bug or button camera if it had lead over it?

The first job was to rig these switches.

Jonnie made a trip to electronics stores and got what he wanted. He came back to find that Ker had swept the area for bugs and found none.

They chose where Terl would do his shopwork: in Chirk's former reception office. It was big enough to work in and the size console it would be would go in and out of the door.

While Jonnie, at his desk, worked on the bug probe, the other two rigged a workbench out of a metal slab and welded it to the floor and then armor annealed the welds so it would be an awful lot of trouble to move. They even got a stool and put it in front of it. When they had finished, they had a very nice layout. Jonnie moved his work over to it.

He had made excellent progress. Using microbutton transmitters employed normally in remote controls, he had rigged every switch in the probe so that when it was turned on it would send out an impulse from the remote relay. These relays took a microscope to see properly. They were fastened in with a small molecular spray. The worst part was getting them to stay where one wanted them while spraying them down. But the eye that could detect them unaided had never been made.

Using a scope set at a distance from the probe, he clicked each switch on in turn and the scope bounced in response.

The next part was hard because it involved the adaption of iris leaves taken from tubes of plane viewers. These were small devices that automatically adjusted the volume of a light path. They would close their concentric leaves from wide open to shut.

They had to take these delicate things apart and spray them, molecules thick, with lead and reassemble them so they would not only work but would go on working, opening and closing. Angus was the best at this sort of work.

They then got some contraction rings and put them around these leaded irises and installed microbuttons in them to activate them.

When they had built about fifteen of these, they made a thorough and extensive test. When the probe was clicked on the iris instantly closed. When the probe was turned off the irises sprang open.

In other words, the leaded irises would be shut whenever the probe was on, thus putting a lead screen over any bug and making it undetectable and for the moment unable to “see” and “hear.” But when the probe was off, the screen would be off and any bug or device could “see” and “hear.”

So far so good. They now went on an extensive tour of storerooms– telling Lars, who showed up, that they were looking for "spindle-buffers"-and located not only every other bug probe in the compound but also every other key component it took to make a bug probe. They put these in a box and put the box in their car to be transported out of the country.