'Less than ten?'

'I think,' said Teppic, 'it would be best to say a number between zero and ten.'

'Just so long as I know. These things are important.' They strolled back to You Bastard. But now it was Teppic who seemed to have something on his mind.

'All this senate . . .' he said.

'Congress,' corrected Ptraci.

'You . . . er . . . more than fifty people?'

'There's a different name for that sort of woman,' said Ptraci, but without much rancour.

'Sorry. Less than ten?'

'Let's say,' said Ptraci, 'a number between zero and ten.' You Bastard spat. Twenty feet away the blowfly was picked cleanly out of the air and glued to the rock behind it.

'Amazing how they do it, isn't it,' said Teppic. 'Animal instinct, I suppose.'

You Bastard gave him a haughty glare from under his sweep-the-desert eyelashes and thought:

. . . Let z=ei0. cudcudcud Then dz=ie[i0]d0=izd0 or d0=dz/iz . . .

Ptaclusp, still in his nightshirt, wandered aimlessly among the wreckage at the foot of the pyramid.

It was humming like a turbine. Ptaclusp didn't know why, knew nothing about the vast expenditure of power that had twisted the dimensions by ninety degrees and was holding them there against terrible pressures, but at least the disturbing temporal changes seemed to have stopped. There were fewer sons around than there used to be; in truth, he could have done with finding one or two.

First he found the capstone, which had shattered, its electrum sheathing peeling away. In its descent from the pyramid it had hit the statue of Hat the Vulture-Headed God, bending it double and giving it an expression of mild surprise.

A faint groan sent him tugging at the wreckage of a tent. He tore at the heavy canvas and unearthed IIb, who blinked at him in the grey light.

'It didn't work, dad!' he moaned. 'We'd almost got it up there, and then the whole thing just sort of twisted!'

The builder lifted a spar off his son's legs.

'Anything broken?' he said quietly.

'Just bruised, I think.' The young architect sat up, wincing, and craned to see around.

'Where's Two-ay?' he said. 'He was higher up than me, nearly on the top-'

'I've found him,' said Ptaclusp.

Architects are not known for their attention to subtle shades of meaning, but IIb heard the lead in his father's voice.

'He's not dead, is he?' he whispered.

'I don't think so. I'm not sure. He's alive. But. He's moving - he's moving . . . well, you better come and see. I think something quantum has happened to him.'

You Bastard plodded onwards at about 1.247 metres per second, working out complex conjugate co-ordinates to stave off boredom while his huge, plate-like feet crunched on the sand.

Lack of fingers was another big spur to the development of camel intellect. Human mathematical development had always been held back by everyone's instinctive tendency, when faced with something really complex in the way of triform polynomials or parametric differentials, to count fingers. Camels started from the word go by counting numbers.

Deserts were a great help, too. There aren't many distractions. As far as camels were concerned, the way to mighty intellectual development was to have nothing much to do and nothing to do it with.

He reached the crest of the dune, gazed with approval over the rolling sands ahead of him, and began to think in logarithms.

'What's Ephebe like?' said Ptraci.