Moist was fidgeting at this point, and he chimed in with, ‘Excuse me, I know you said that Simnels have been working on steam for years and that other people might have been too, but do you know if anybody else has anything like this? Might they steal a march on you even if they don’t have your secrets?’

To his surprise Simnel said cheerfully, ‘Oh yes, sir, about four or five of them, but none of them have yet produced even a working concept like Iron Girder. They’re making all t’mistakes my dad did, and making a few others of their own an’ all, from what I hear. Superheated steam doesn’t give you a chance. Get it wrong and it’ll tek t’flesh off your bones. Now me, sir, well, I’m a stickler for measurements, tiny teeny weeny measurements. They ain’t very exciting but that’s the soul and centre of being an engineering artificer.

‘Unfortunately, my granddad and my dad were a bit slapdash about them, seeing as they didn’t have the proper knowing of them, but measurements is your saving grace if you want to raise steam. Me mum paid for me to get a better learning, being as ’er side of the family had money from …’ he paused, ‘fishing, and one of my uncles made theodolites and other delicate instruments, and I thought to meself, well, this is very helpful, especially when he taught me ’ow to blow glass, and what I need glass for is my own little secret …’

Simnel looked anxious for a moment and said, ‘I’ll need a shedload of iron, especially for t’tracks themselves. And, of course, then there’s the question of laying t’tracks through people’s land … someone’ll have to talk to the landowners. I’m an engineer, always will be, and I’m not sure I know how to ’aggle with the big nobs.’

‘Ah, as it happens we have a born haggler with us right now,’ said Harry. ‘What do you say, Mister Lipwig? Do you want to be a part of it?’

Moist opened his mouth to speak.

‘There you are, then, young Dick. We’ll use Mister Lipwig for any negotiations. He’s the kind of man who’d follow you into a revolving door and still come out in front. And he speaks posh, when necessary. Of course, he’s a bit of a scoundrel, but aren’t we all in this business?’

‘I don’t think I am, sir,’ said Simnel cautiously, ‘but I know what you mean. If you don’t mind, I’d like to suggest that my first track is laid all the way back to Sto Lat. Well, not exactly Sto Lat, it’s a place on the outskirts called Swine Town, there being so many pigs in the area. That’s where the rest of my gear and machinery is stored.’

Simnel looked nervously at Sir Harry, who was pursing his lips. ‘It’s a long way, lad, must be twenty-five miles or more, and you’d be right out in the sticks there.’