College led my grandfather out onto Broadway and walked him between the walls of buildings and up to the ponds and hillocks of Central Park. Then downtown again. They hung onto the straps of a horse-drawn streetcar, bought hot chestnuts from a sidewalk vendor, watched the traffic of ships from a bench in the Battery. There were barks and barkentines, steeply raked schooner clippers designed for the Gold Rushes in Australia and California – even a whaler on its way back to New Bedford. Jonathan stood up and sat in abrupt movements, twisting to catch sight of the ships, and of the passers-by, too, any one of whom might be a man with a black beard and no lashes on one eye. After all, this is America. Everybody’s on the move.

So here he is in New York, seeking a father never to be found and knowing himself a murderer, which he is not, when all of a sudden he sees George. Right there in the Battery. There he is – plump, dark-haired, a frock coat. Of course it’s George. Jonathan makes a dash at him, grabs him by the shoulder, swings him around –

And it isn’t George at all.

That night Jonathan dreamed again the nightmare that had spurred him on to run away from Denver. Again he awoke to find himself plucking imaginary tobacco worms from his covers. But three days later the multi-colored Mogul pulled out of New York carrying the makings of an entire town, and as everybody knows – Jonathan better than most – when you move you can stop thinking: maybe even stop dreaming. They carried every nail with them, every scrap of timber, every tin of beans: every citizen, too, school teacher, preacher, saloon keeper, men, women, children. Secret reports revealed stibnite in a remote area of Nevada. Out of stibnite you can make explosives. Provided you get there first, that is. A company called Metals & Minerals of New York was getting there first.

When they reached the site of the town, they christened it Mogul in the engine’s honor, and a month after the raw materials were dumped in the desert, Jonathan and College passed through the area again, this time going east with redwood trunks from California chained to flatcars and bound for Chicago. Balancing on the trunks, they looked down on the population of the town – men, women, children – everybody sawing and hammering, fetching and carrying, a busyness as busy from the top of a train as a plague of locusts from the window of a wooden farmhouse. The hotel was already complete. So was the general store. So was the boardwalk. A saloon without walls was in business. Struts for a church spire rose up not far from struts that would become a train station. The foundations of a dozen houses clustered beyond the boardwalk.

Jonathan had plainly been a charming small child once, chattering nonsense and dancing around cracker barrels in Benbow Wikin’s store; he’d smothered this gaiety to survive, killed it, he thought, as surely as he’d killed George. He was as wrong about the one as about the other (as most people are about the certainties in their lives). The gaiety was rare, but it shows itself in the diaries sometimes, a complete surprise when it happens, as pleasurable as dashing through a sprinkler on a hot day. ‘Hey,’ he shouted in delight to College over the roar of the engine, looking down on the doings of this boom-town-to-be, ‘hey! I helped build that.’ What would such a place be in two years’ time? In ten? Could you contain it at all?