Simony looked at the skeleton of the steam car and the pile of plates stacked beside it.
“Ever been in a battle, Urn?” he said.
“No. I've got flat feet. And I'm not very strong.”
“Do you know what a tortoise is?”
Urn scratched his head. “Okay. The answer isn't a little reptile in a shell, is it? Because you know I know that.”
“I mean a shield tortoise. When you're attacking a fortress or a wall, and the enemy is dropping everything he's got on you, every man holds his shield overhead so that it . . . kind of . . . slots into all the shields around it. Can take a lot of weight.”
“Overlapping,” murmured Urn.
“Like scales,” said Simony.
Urn looked reflectively at the cart.
“A tortoise,” he said.
“And the battering-ram?” said Simony.
“Oh, that's no problem,” said Urn, not paying much attention. “Tree-trunk bolted to the frame. Big iron rammer. They're only bronze doors, you say?”
“Yes. But very big.”
“Then they're probably hollow. Or cast bronze plates on wood. That's what I'd do.”
“Not solid bronze? Everyone says they're solid bronze.”
“That's what I'd say, too.”
“Excuse me, sirs.”
A burly man stepped forward. He wore the uniform of the palace guards.
“This is Sergeant Fergmen,” said Simony. “Yes, sergeant?”
“The doors is reinforced with Klatchian steel. Because of all the fighting in the time of the False Prophet Zog. And they opens outwards only. Like lock gates on a canal, you understand? If you push on 'em, they only locks more firmly together.”
“How are they opened, then?” said Urn.
“The Cenobiarch raises his hand and the breath of God blows them open,” said the sergeant.
“In a logical sense, I meant.”
“Oh. Well, one of the deacons goes behind a curtain and pulls a lever. But . . . when I was on guard down in the crypts, sometimes, there was a room . . . there was gratings and things . . . well, you could hear water gushing . . .”
“Hydraulics,” said Urn. “Thought it would be hydraulics.”
“Can you get in?” said Simony.
“To the room? Why not? No one bothers with it.”
“Could he make the doors open?” said Simony.
“Hmm?” said Urn.
Urn was rubbing his chin reflectively with a hammer. He seemed to be lost in a world of his own.