He lunched at the Merchants’ Association Club, often sitting alone at a corner table. A week before Christmas, he moved out of the Tuckers’s house and rented the second-storey rooms of a house on J Street, within sight of Sutter’s Fort. Some evenings he spent alone, reading and smoking and drinking whisky; but two or three times a week he went to the Auburn Saloon on H Street or the Duffy House on I, where he played faro until two or three in the morning.

There was a passable whorehouse on the corner of Eighth and L Streets, Mrs Pangborn’s, a four-storey frame building painted ochre-red, with green blinds that were always drawn. Collis went there once or twice a month, following along the musty corridors the firm buttocks of some girl dressed in nothing but a silk-panelled corset, and then lying in bed afterwards breathing in the smell of musk and sweat and listening to the distant repetitive banging of the house pianist’s heel on the worn-out rugs downstairs.

He spent Christmas with Theodore and Annie Jones. It was a gentle, emotional day, and he found he was beginning to understand and love them both. Theodore carved the goose, and after their dinner they exchanged gifts. Collis had bought Theodore a bound monograph on the rolling of permanent way at Mount Savage, in Maryland, and a bottle of rose-scented toilet water for Annie. In return, the Joneses gave him a travelling-case with razor and scissors and hairbrushes, all engraved ‘CE’. They stood in front of the fire and sang Christmas carols, unselfconsciously and with joy.

As 1858 began, Collis also began to deepen his friendship with Wang-Pu. They rarely dined out together, since a merchant of Collis’s standing was considered eccentric and even anti-social if he ate with a Chinese, and both Collis and Wang-Pu decided that the interests of the Sierra Pacific railroad would be better served if Collis kept up his local respectability. But they spent many evenings in the calm simplicity of Wang-Pu’s apartment, where Collis learned to sit on the floor crosslegged and eat with chopsticks, and where he learned the subtle pleasures of wind-dried ducks, kai-choy, and pig’s-trotter jelly.

Wang-Pu talked about the summers in North China, and of outdoor feasts with his family, when they would eat so many river crabs that they would be sitting ankle-deep in empty shells. He talked of Buddhism, and of Chinese funerals and marriages. He tried to explain the visions in his mind.

These evenings always left Collis feeling peaceful and whole, and although he was still determined to press ahead with his railroad, as hard and as fast as he could, he began to see himself more clearly, and his ambition took on a shape that was as unmistakable as the distant peaks of the Sierra Nevada.