He walked straight ahead and then he couldn't go any further. He could not walk through the air before him!

He threw a rock at it. The rock bounced! He tried again, throwing harder. Same result.

He had Angus open the bus bar again. No barrier! Closed. Barrier!

For the next two hours, by opening and closing the first and second row of bus bars and throwing rocks, they found that the dam itself was surrounded by a protective screen. The bowl had a screen all around its top and was completely enclosed!

Riflemen even fired shots at it and they glanced off.

At Stage Two the air got a bit shimmery, and Angus reported the power output meters were lower. At Stage Three there was a strange electrical smell in the air and the output meters of the total dam power dropped way down.

Defense and more defense. A transshipment platform operating in that bowl could not be interfered with by attack. Not from the sides and not from above. And neither could the dam.

The amount of raw power it took to operate it was a large portion of the total output of this huge dam, and Jonnie surmised that they changed stages of output to repel extreme attack and then eased them off to Stage One when they needed power to transship.

Jonnie had them booby-trap the entrances in case their visitors upstairs came down for a look and prowl. And they took off in the early afternoon for home.

A glimmer of hope. Not much, but a glimmer, Jonnie told Sir Robert on the way home.

He wanted Sir Robert, Jonnie said, to take charge in the African area for the moment for Jonnie had some other things to look into elsewhere. He rebriefed the grizzled War Chief on the existing situation: they were threatened by a possible counterattack from Psychlo; the visitors upstairs were waiting for something– he did not know what, but he was certain they would eventually strike; the political scene in America was a lesser menace but existed and they had to let it go on for now. The thing that would solve their troubles, Jonnie said, was to get control of teleportation or at least an operating console; with that they could operate far more widely, but it seemed to be the most closely guarded secret the Psychlos had, and avenues to cracking it were not very hopeful.

The main problem, Jonnie said, was protecting what was left of the human race; they were no longer very numerous; a wide attack by the visitors or a counterattack by Psychlo could, either one, finish them as a race forever. Jonnie, as soon as they landed, was going to leave for Russia to begin to handle this point.

Would Sir Robert, Jonnie concluded, take a few local protective measures which Jonnie then named.

Robert the Fox said he was honored and certainly would. Such things were easily done, but did Jonnie much care what happened to any visitors who might wander down?

Jonnie said no. And Sir Robert smiled.

The Bolbod punchcraft was quite clear on the screen. Cylindrical, a small miniature of the Bolbod war vessel from which it came, it was about to make its landing near the dam.

The small gray man sat in his small gray office and watched. He was mildly interested in a detached sort of way.

He was very glad he had asked his communications officer to install the racks and extra screens. A Jambitchow war vessel had joined them– commanded by an officer in glittering gold scales and eyes where his mouth ought to be– had been informed of the situation, had been told that they didn't know yet whether this was the one, had agreed to join the combined force, and was now in orbit with the rest. The Jambitchow face was now on its own viewscreen, watching, like the rest, the outcome of this “punch” as the Bolbod called it. Six screens, five of them with intent faces, the sixth carrying the long-range view of this raid.

For the last few days the small gray man had felt much better. It had been a good idea to go down and see that old woman again. She was certain it could not have been her yarb tea that had caused his indigestion. Had he drunk anything in some heathen country? Well, never mind, drink this “buttermilk.”

He had drunk the buttermilk. It was quite cold and good to taste and shortly his indigestion had greatly eased. But the old woman had not let it go at that. A cousin in some distant past had sent some plants to some ancestors of hers and they were still flourishing up the hill near the spring. It was called “peppermint” and she would go get some, and she had, steering a bit wide around the parked spaceship. The green leaves had a pleasant aroma and he had chewed some, and astonishingly, his indigestion eased even more! She had given him a whole pocketful of the leaves.

The small gray man had tried to pay her but she wouldn't have it; she said it was just the neighborly thing to do. He had persisted however, and she finally said, well, there was a Swedish colony up the coast she was never able to talk to, and that thing around his neck, the one he talked into and it talked English, would it talk Swedish? He'd been happy to give it to her– he had several– and had changed its microplates while sitting pleasantly on a bench outside her door with both the dog and the cow seemingly quite interested in what he was doing. It had been a pleasant afternoon.

The Bolbod punchcraft banged down near the overgrown walkway at the dam. They were carrying a demolition kit.

“I thought this was just a probe,” said the Hawvin. “Didn't we agree they were just to discover what those people had done down at that dam?” They had watched the terrestrial antics around them, had seen them blow up a bunch of trees, and their curiosity had been greatly aroused.

No heat had accompanied the eruption of trees and nothing had burned. "If we use demolition on the dam, it could become political.”

“I command my own crew,” rumbled the Bolbod on his screen. That was the trouble with combined forces, everyone tried to run everybody else's ship! But combined force had been his idea so he couldn't say much more.

There had been three Bolbod crewmen in the punchcraft. The first one, carrying the demolition kit, was followed at some distance by the other two.

The faces on the viewscreens were very intent as they followed this operation. It was their first probe down to the surface. The small gray man had tended to advise against it but this was a military matter. They all knew that one must test the enemy's defenses.

The leading Bolbod was now about fifty feet from the powerhouse door. The roar of the spillway was coming back up the infrabeam, very strong. That was an awfully big dam.

Abruptly there was a flash!

A rolling ball of flame rocketed skyward.

The image on the screen jittered from the concussion.

The first Bolbod had vanished, blown to bits. Whatever he tripped had also detonated his own demolition kit.

The other two Bolbods who had been well behind him had been knocked flat.

“Aha!” said the Hockner super-lieutenant as though he had known it all the time.

But the “aha!” wasn't for the explosion. A marine attack plane that a moment before hadn't been on their screens landed clear of the explosion area. A small unit of people leaped out.

Swedes, thought the small gray man, seeing their blonde hair. Led by a black-bearded young officer in kilts who carried a claymore and a blast pistol.

A ramp went down on the attack plane's side and a forklift rolled to the ground.

The Swedes had some chains in their hands and were wrapping up the two recumbent Bolbods. Thin little shouts of command were coming back up the infrabeam, almost engulfed by the roar of the dam spillway.