Urn selected a short crowbar from his belt and inserted it between the grille and the stonework. Give me a foot of good steel and a wall to brace . . . my . . . foot . . . against-the grille ground forward and then popped out with a leaden sound-and I can change the world . . .
He stepped inside the long, dark, damp room, and gave a whistle of admiration.
No one had done any maintenance for-well, for as long as it took iron hinges to become a mass of crumbling rust-but all this still worked?
He looked up at lead and iron buckets bigger than he was, and a tangle of man-sized pipes.
This was the breath of God.
Probably the last man who knew how it worked had been tortured to death years before. Or as soon as it was installed. Killing the creator was a traditional method of patent-protection.
There were the levers and there, hanging over pits in the rock floor, were the two sets of counterweights. Probably it'd only take a few hundred gallons of water to swing the balance either way. Of course, the water'd have to be pumped up-
“Sergeant?”
Fergmen peered round the door. He looked nervous, like an atheist in a thunderstorm.
“What?”
Urn pointed.
“There's a big shaft through the wall there, see? At the bottom of the gear-chain?”
“The what?”
“The big knobbly wheels?”
“Oh. Yeah.”
“Where does the shaft go to?”
“Don't know. There's the big Treadmill of Correction through there.”
Ah.
The breath of God was ultimately the sweat of men. Didactylos would have appreciated the joke, Urn thought.
He was aware of a sound that had been there all the time but was only now penetrating through his concentration. It was tinny and faint and full of echoes, but it was voices. From the pipes.
The sergeant, to judge by his expression, had heard them too.
Urn put his ear to the metal. There was no possibility of making out words, but the general religious rhythm was familiar enough.
“It's just the service going on in the Temple,” he said. “It's probably resonating off the doors and the sound's being carried down the pipes.”
Fergmen did not look reassured.
“No gods are involved in any way,” Urn translated. He turned his attention to the pipes again.
“Simple principle,” said Urn, more to himself than to Fergmen. “Water pours into the reservoirs on the weights, disturbing the equilibrium. One lot of weights descends and the other rises up the shaft in the wall. The weight of the door is immaterial. As the bottom weights descend, these buckets here tip over, pouring the water out. Probably quite a smooth ac?tion. Perfect equilibrium at either end of the move?ment, too. Nicely thought out.”
He caught Fergmen's expression.
“Water goes in and out and the doors swing open,” he translated. “So all we've got to do is wait for . . . what did he say the sign would be?”
“They'll blow a trumpet when they're through the main gate,” said Fergmen, pleased to be of service.
“Right.” Urn eyed the weights and the reservoirs overhead. The bronze pipes dripped with corrosion.