'I call it a Nextahedron,' announced Mycroft, picking up the solid and placing it on the floor, where it continued its random perambulations, watched by Pickwick, who thought it might be chas
ing her, and ran away to hide. 'Most irregular solids are only unstable on one or two faces. The Nextahedron is unstable on all its faces - it will continue to fall and tip until a solid object impedes its progress.'
'Fascinating!' I murmured, always surprised by the ingenuity of Mycroft's inventions. 'But what's the point?'
'Well,' explained Mycroft, warming to the subject, 'you know those inertia! generator things that self-wind a wristwatch?'
'Yes?'
'If we have a larger one of those inside a Nextahedron weighing six hundred tons, I calculate we could generate as much as a hundred watts of power.'
'But. . . but that's only enough for a light bulb!'
'Considering the input is nil, I think it's a remarkable achievement,' replied Mycroft somewhat sniffily. 'To generate significant quantities of power we'd have to carve something of considerable mass - Mars, say — into a huge Nextahedron with a flat plate falling around the exterior, held firm by gravity. The power could be transmitted to earth using Tesla beams and . . .'
His voice trailed off as he started to sketch ideas and equations in a small notebook. I watched the Nextahedron fall and rock and jiggle across the floor until it fell against a roll of wire.
'On a more serious note,' confided Polly, putting down her tea, 'you could help us identify some of the devices in the workshop. Since both Mycroft and I have taken the Big Blank you might be able to help.'
'I'll try,' I said, looking around the room at the bizarre devices. 'That one over there guesses how many pips there are in an unopened orange, the one with the horn is an Olfactrograph for measuring smells, and the small box thing there can change gold into lead.'
'What's the point of that?'
'I'm not entirely sure.'
Polly made notes against her inventory and I spent the next ten minutes trying to name as many of Mycroft's inventions as I could. It wasn't easy. He didn't tell me everything.
'I'm not sure what this one is, either,' I said, pointing at a small machine about the size of a telephone directory lying on a workbench.
'Oddly enough,' replied Polly, 'this is one we do have a name for. It's an ovinator.'
'How do you know if you can't remember?'
'Because,' said Mycroft, who had finished his notes and now rejoined us, 'it has "ovinator" engraved on the case just there. We think it's either a device for making eggs without the need of a chicken, or for making chickens without the need of an egg. Or something else entirely. Here, I'll switch it on.'
Mycroft flicked a switch and a small red light came on.
'Is that it?'
'Yes,' replied Polly, staring at the small and very unexciting metallic box thoughtfully.
'No sign of any eggs or chickens,' I observed.
'None at all.' Mycroft sighed. 'It might just be a machine for making a red light come on. Drat my lost memory! Which reminds me: any idea which device actually is the memory eraser?'
We looked around the workshop at the odd-looking and mostly anonymous contraptions. Any one of them may have been used to erase memories, but then any one of them may have been a device for coring apples, too.
We stood in silence for a moment.
'I still think you ought to have Smudger on defence,' said Polly, who was probably the biggest croquet fan in the house.
'You're probably right,' I said, suddenly feeling that it would be easier just to go with the flow. 'Uncle?'
'Polly knows best,' he replied. 'I'm a bit tired. Who wants to watch Name That Fruit on the telly?'
We all agreed that it would be a relaxing way to end the day and I found myself watching the nauseating quiz show for the first time in my life. I realised just how bad it was halfway through, and went to bed, temples aching.
30