It is hard to understand nothing, but the multiverse is full of it. Nothing travels everywhere, always ahead of something, and in the great cloud of unknowing nothing yearns to become something, to break out, to move, to feel, to change, to dance and to experience—in short, to be something.

And now it found its chance as it drifted in the ether. Nothing, of course, knew about something, but this something was different, oh yes, and so nothing slid silently into something and floated down with everything in mind and, fortunately, landed on the back of a turtle, a very large one, and hurried to become something even faster. It was elemental and nothing was better than that and suddenly the elemental was captured! The bait had worked.

Anyone who has ever seen the River Ankh sliding along its bed of miscellaneous nastiness would understand why so much of the piscine food for the people of Ankh-Morpork has to be supplied by the fishing fleets of Quirm. In order to prevent terrible gastric trouble for the citizenry, Ankh-Morpork fishmongers have to ensure that their suppliers make their catches a long, long way from the city.

For Bowden Jeffries, purveyor of the very best in seafood, the two hundred miles or more which lay between the fish docks at Quirm and the customers in Ankh-Morpork was a regrettably long distance throughout the winter, autumn, and spring and a sheer penance in the summertime, because the highway, such as it was, became a linear furnace all the way to the Big City. Once you had had to deal with a ton of overheated octopus, you never forgot it; the smell lasted for days, and followed you around and almost into your bedroom. You could never get it out of your clothes.

People were so demanding, but the elite of Ankh-Morpork and, indeed, everyone else wanted their fish, even in the hottest part of the season. Even with an icehouse built by his own two hands and, by arrangement, a second icehouse halfway along the journey, it made you want to cry, it really did.

And he said as much to his cousin, Relief Jeffries, a market gardener, who looked at his beer and said, “It’s always the same. Nobody wants to help the small entrepreneur. Can you imagine how quickly strawberries turn into little balls of mush in the heat? Well, I’ll tell you: no time at all. Blink and you miss ’em, just when everybody wants their strawberries. And you ask the watercress people how difficult it is to get the damn stuff to the city before it’s as limp as a second-day sermon. We should petition the government!”

“No,” said his cousin. “I’ve had enough of this. Let’s write to the newspapers! That’s the way to get things done. Everyone’s complaining about the fruit and vegetables and the seafood. Vetinari should be made to understand the plight of the small-time entrepreneur. After all, what do we occasionally pay our taxes for?”

Dick Simnel was ten years old when, back at the family smithy in Sheepridge, his father simply disappeared in a cloud of furnace parts and flying metal, all enveloped in a pink steam. He was never found in the terrible haze of scorching dampness, but on that very day young Dick Simnel vowed to whatever was left of his father in that boiling steam that he would make steam his servant.

His mother had other ideas. She was a midwife, and as she said to her neighbors, “Babbies are born everywhere. I’ll never be without a customer.” So, against her son’s wishes, Elsie Simnel decided to take him away from what she now considered to be a haunted place. She packed up their belongings and together they returned to her family home near Sto Lat, where people didn’t inexplicably disappear in a hot pink cloud.

Soon after they arrived something important happened to her boy. One day while waiting for his mother to return from a difficult delivery, Dick walked into a building that looked interesting, and which turned out to be a library. At first he thought it was full of poncy stuff, all kings and poets and lovers and battles, but in one crucial book he found something called mathematics and the world of numbers.

And that was why, one day some ten years later, he pulled together every fibre of his being and said, “Mother, you know last year when I said I were going ’iking in the mountains of Uberwald with me mates, well, it were kind of . . . sort of . . . a kind of lie, only very small, mind you.” Dick blushed. “You see, I found t’keys to Dad’s old shed and, well, I went back to Sheepridge and did some experimenting and”—he looked at his mother anxiously “—I think I know what ’e were doing wrong.”

Dick was braced for stiff objections, but he hadn’t reckoned on tears—so many tears—and as he tried to console her he added, “You, Mother, and Uncle Flavius got me an education, you got me the knowing of the numbers, including the arithmetic and weird stuff dreamed up by the philosophers in Ephebe where even camels can do logarithms on their toes. Dad didn’t know this stuff. He had the right ideas but he didn’t have the . . . tech-nol-ogy right.”

At this point, Dick allowed his mother to talk, and she said, “I know there’s no stopping you, our Dick, you’re just like your stubborn father were, pigheaded. Is that what you’ve been doin’ in the barn? Teck-ology?” She looked at him accusingly, then sighed. “I can see I can’t tell you what to do, but you tell me: how can your ‘logger-reasons’ stop you goin’ the way of your poor old dad?” She started sobbing again.

Dick pulled out of his jacket something that looked like a small wand, which might have been made for a miniature wizard, and said, “This’ll keep me safe, Mother! I’ve the knowing of the sliding rule! I can tell the sine what to do, and the cosine likewise and work out the tangent of t’quaderatics! Come on, Mother, stop fretting and come wi’ me now to t’barn. You must see ’er!”

Mrs. Simnel, reluctant, was dragged by her son to the great open barn he had kitted out like the workshop back at Sheepridge, hoping against hope that her son had accidentally found himself a girl. Inside the barn she looked helplessly at a large circle of metal which covered most of the floor. Something metallic whizzed round and round on the metal, sounding like a squirrel in a cage, giving off a smell much like camphor.

“Here she is, Mother. Ain’t she champion?” Dick said happily. “I call her Iron Girder!”

“But what is it, son?”

He grinned hugely and said, “It’s what they call a pro-to-type, Mother. You’ve got to ’ave a pro-to-type if you’re going to be an engineer.”

His mother smiled wanly but there was no stopping Dick. The words just tumbled out.

“The thing is, Mother, before you attempt owt you’ve got to ’ave some idea of what it is you want to do. One of the books I found in the library was about being an architect. And in that book, the man who wrote it said before he built his next big ’ouse he always made quite tiny models to get an idea of how it would all work out. He said it sounds fiddly and stuff, but going slowly and being thorough is the only way forward. And so I’m testing ’er out slowly, seeing what works and what doesn’t. And actually, I’m quite proud of me’sen. In the beginning I made t’track wooden, but I reckoned that the engine I wanted would be very ’eavy, so I chopped up t’wooden circle for firewood and went back to t’forge.”

Mrs. Simnel looked at the little mechanism running round and round on the barn floor and said, in the voice of someone really trying to understand, “Eee, lad, but what does it do?”

“Well, I remembered what Dad said about t’time he were watching t’kettle boiling and noticed t’lid going up and down with the pressure, and he told me that one day someone would build a bigger kettle that would lift more than a kettle lid. And I believe I have the knowing of the way to build a proper kettle, Mother.”

“And what good would that do, my boy?” said his mother sternly. And she watched the glow in her son’s eyes as he said, “Everything, Mother. Everything.”

Still in a haze of slight misunderstanding, Mrs. Simnel watched him unroll a large and rather grubby piece of paper.

“It’s called a blueprint, Mother. You’ve got to have a blueprint. It shows you how everything fits together.”

“Is this part of the pro-to-type?”

The boy looked at his doting mother’s face and realized that a little more exposition should be forthcoming. He took her by the hand and said, “Mother, I know they’re all lines and circles to you, but once you have the knowing of the circles and the lines and all, you know that this is a picture of an engine.”

Mrs. Simnel gripped his hand and said, “What do you think you’re going to do with it, our Dick?”

And young Simnel grinned and said happily, “Change things as needs changing, Mother.”

Mrs. Simnel gave her son a curious look for a moment or two, then appeared to reach a grudging conclusion and said, “Just you come with me, my lad.”

She led him back into the house, where they climbed up the ladder into the attic. She pointed out to her son a sturdy seaman’s chest covered in dust.

“Your granddad gave me this to give to you, when I thought you needed it. Here’s the key.”

She was gratified that he didn’t grab it and indeed looked carefully at the trunk before opening it. As he pushed up the lid, suddenly the air was filled with the glimmer of gold.

“Your granddad were slightly a bit of a pirate and then he got religion and were a bit afeared, and the last words he said to me on his deathbed were, ‘That young lad’ll do something one day, you mark my words, our Elsie, but I’m damned if I know what it’s going to be.’ ”

The people of the town were quite accustomed to the clangings and bangings emanating every day from the various blacksmith forges for which the area was famous. It seemed that, even though he had set up a forge of his own, young Simnel had decided not to enter the blacksmithing trade, possibly due to the dreadful business of Mr. Simnel Senior’s leaving the world so abruptly. The local blacksmiths soon got used to making mysterious items that young Mr. Simnel had sketched out meticulously. He never told them what he was constructing, but since they were earning a lot of money they didn’t mind.

The news of his legacy got around, of course—gold always finds its way out somehow—and there was a scratching of heads among the population exemplified by the oldest inhabitant, who, sitting on the bench outside the tavern, said, “Well, bugger me! Lad were blessed wi’ an inherited fortune in gold and turned it into a load of old iron!”

He laughed, and so did everybody else, but nevertheless they continued to watch young Dick Simnel slip in and out of the wicket gate of his old and almost derelict barn, double-padlocked at all times.

Simnel had found a couple of local likely lads who helped him make things and move things around. Over time, the barn was augmented by a host of other sheds. More lads were taken on and the hammers were heard all day every day and, a bit at a time, information trickled into what might be called the local consciousness.

Apparently the lad had made a pump, an interesting pump that pumped water very high. And then he’d thrown everything away and said things like, “We need more steel than iron.”

There were tales of great reams of paper laid out on desks as young Simnel worked out a wonderful “undertaking,” as he called it. Admittedly there had been the occasional explosion, and then people heard about what the lads called “the Bunker,” which had been useful to jump into on several occasions when there had been a little . . . incident. And then there was the unfamiliar but somehow homely and rhythmic “chuffing” noise. Really quite a pleasant noise, almost hypnotic, which was strange because the mechanical creature that was making the noise sounded more alive than you would have expected.

It was noticed in the locality that the two main coworkers of Mr. Simnel, or “Mad Iron” Simnel as some were now calling him, seemed somewhat changed, more grown‑up and aware of themselves; young men, acolytes of the mysterious thing behind the doors. And no amount of bribery by beer or by women in the pub would make them give up the precious secrets of the barn. They conducted themselves now as befitted the masters of the fiery furnace.

And then, of course, there were the sunny days when young Simnel and his cohorts dug long lines in the field next to the barn and filled them with metal while the furnace glowed day and night and everyone shook their heads and said, “Madness.” And this went on, it seemed forever, until ever was finished and the banging and clanging and smelting had stopped. Then Mr. Simnel’s lieutenants pulled aside the double doors of the big barn and filled the world with smoke.

Very little happened in this part of Sto Lat and this was enough to bring people running. Most of them arrived in time to see something heading out toward them, panting and steaming, with fast-spinning wheels and oscillating rods eerily appearing and disappearing in the smoke and the haze, and on top of it all, like a sort of king of smoke and fire, Dick Simnel, his face contorted with the effort of concentration. It was faintly reassuring that this something was apparently under the control of somebody human—although the more thoughtful of the onlookers might have added “So what? So’s a spoon,” and got ready to run away as the steaming, dancing, spinning, reciprocating engine cleared the barn and plunged on down the tracks laid in the field. And the bystanders, most of whom were now byrunners, and in certain instances bystampeders, fled and complained, except, of course, for every little boy of any age who followed it with eyes open wide, vowing there and then that one day he would be the captain of the terrible noxious engine, oh yes indeed. A prince of the steam! A master of the sparks! A coachman of the Thunderbolts!