His hands and feet felt too cold. Foolish, foolish. He should have done this before.

The boat jerked slowly into midstream as full night rolled over the valley. On the far bank, in response to the ancient laws, the pyramids started to light the sky.

Lights also burned late in the house of Ptaclusp Associates, Necropolitan Builders to the Dynasties. The father and his twin Sons were hunched over the huge wax designing tray, arguing.

'It's not as if they ever pay,' said Ptaclusp IIa. 'I mean it's not just a case of not being able to, they don't seem to have grasped the idea. At least dynasties like Tsort pay up within a hundred years or so. Why didn't you-'

'We've built pyramids along the Djel for the last three thousand years,' said his father stiffly, 'and we haven't lost by it, have we? No, we haven't. Because the other kingdoms look to the Djel, they say there's a family that really knows its pyramids, connysewers, they say we'll have what they're having, if you please, with knobs on. Anyway, they're real royalty,' he added, 'not like some of the ones you get these days - here today, gone next millennium. They're half gods, too. You don't expect real royalty to pay its way. That's one of the signs of real royalty, not having any money.'

'You don't get more royal than them, then. You'd need a new word,' said IIa. We're nearly royal in that case.'

'You don't understand business, my son. You think it's all book-keeping. Well, it isn't.'

'It's a question of mass. And the power to weight ratio.' They both glared at Ptaclusp IIb, who was sitting staring at the sketches. He was turning his stylus over and over in his hands, which were trembling with barely-suppressed excitement.

'We'll have to use granite for the lower slopes,' he said, talking to himself, 'the limestone wouldn't take it. Not with all the power flows. Which will be, whooeee, they'll be big. I mean we're not talking razor blades here. This thing could put an edge on a rolling pin.'

Ptaclusp rolled his eyes. He was only one generation into a dynasty and already it was trouble. One son a born accountant, the other in love with this new-fangled cosmic engineering. There hadn't been any such thing when he was a lad, there was just architecture. You drew the plans, and then got in ten thousand lads on time-and-a-half and double bubble at weekends. They just had to pile the stuff up. You didn't have to be cosmic about it.

Descendants! The gods had seen fit to give him one son who charged you for the amount of breath expended in saying 'Good morning', and another one who worshipped geometry and stayed up all night designing aqueducts. You scrimped and saved to send them to the best schools, and then they went and paid you back by getting educated.

'What are you talking about?' he snapped.

'The discharge alone . . .' He pulled his abacus towards him and rattled the pottery beads along the wires. 'Let's say we're talking twice the height of the Executive model, which gives us a mass of. . . plus additional coded dimensions of occult significance as per spec. . . we couldn't do this sort of thing even a hundred years ago, you realise, not with the primitive techniques we had then...' His finger became a blur.

IIa gave a snort and grabbed his own abacus.

'Limestone at two talents the ton. . .' he said. 'Wear and tear on tools . . . masonry charges . . . demurrage . . . breakages . . . oh dear, oh dear . . . on-cost . . . black marble at replacement prices . . .'

Ptaclusp sighed. Two abaci rattling in tandem the whole day long, one changing the shape of the world and the other one deploring the cost. Whatever happened to the two bits of wood and a plumbline?

The last beads clicked against the stops.

'It'd be a whole quantum leap in pyramidology,' said IIb, sitting back with a messianic grin on his face.

'It'd be a whole kwa-' IIa began.

'Quantum,' said IIb, savouring the word.

'It'd be a whole quantum leap in bankruptcy,' said IIa.

'They'd have to invent a new word for that too.'

'It'd be worth it as a loss leader,' said IIb.

'Sure enough. When it comes to making a loss, we'll be in the lead,' said IIa sourly.

'It'd practically glow! In millennia to come people will look at it and say “That Ptaclusp, he knew his pyramids all right”.'

'They'll call it Ptaclusp's Folly, you mean!'

By now the brothers were both standing up, their noses a few inches apart.

'The trouble with you, sibling, is that you know the cost of everything and the value of nothing!'

'The trouble with you is - is - is that you don't!'

'Mankind must strive ever upwards!'