-a sphere of radius r, which therefore had a volume V = (4/3)(pi) rrr, and surface area A = 4(pi) rr-
“Oh, my god . . .”
“What now?” said the voice of the tortoise.
Didactylos's face turned towards Brutha, who was clutching at his head.
“What's a pi?”
Didactylos reached out a hand and steadied Brutha.
“What's the matter?” said Om.
“I don't know! It's just words! I don't know what's in the books! I can't read!”
“Getting plenty of sleep is vital,” said Om. “It builds a healthy shell.”
Brutha sagged to his knees in the rocking boat. He felt like a householder coming back unexpectedly and finding the old place full of strangers. They were in every room, not menacing, but just filling the space with their thereness.
“The books are leaking!”
“I don't see how that can happen,” said Didactylos. “You said you just looked at them. You didn't read them. You don't know what they mean.”
“They know what they mean!”
“Listen. They're just books, of the nature of books,” said Didactylos. “They're not magical. If you could know what books contained just by looking at them, Urn there would be a genius.”
“What's the matter with him?” said Simony.
“He thinks he knows too much.”
“No! I don't know anything! Not really know,” said Brutha. “I just remembered that squids have an internal cartilaginous support!”
“I can see that would be a worry,” said Simony. “Huh. Priests? Mad, the lot of them.”
“No! I don't know what cartilaginous means!”
“Skeletal connective tissue,” said Didactylos. “Think of bony and leathery at the same time.”
Simony snorted. “Well, well,” he said, “we live and learn, just like you said.”
“Some of us even do it the other way round,” said Didactylos.
“Is that supposed to mean something?”
“It's philosophy,” said Didactylos. “And sit down, boy. You're making the boat rock. We're overloaded as it is.”
“It's being buoyed upward by a force equal to the weight of the displaced fluid,” muttered Brutha, sagging.
“Hmm?”
“Except that I don't know what buoyed means.”
Urn looked up from the sphere. “We're ready to start again,” he said. “Just bale some water in here with your helmet, mister.”
“And then we shall go again?”
“Well, we can start getting up steam,” said Urn. He wiped his hands on his toga.