Knickerbocker Jane had nodded. Then, with a flourish, she had sat down again, and set her glass on the wine table beside her.

‘Horace Johnson,’ she said, without any preamble, ‘is a devotee of that very special kind of sport we call “discipline”. He likes to be manacled to the bed, and abused by two or three girls at once.’

‘Horace Johnson?’ Collis had asked, raising his eyebrows.

‘It isn’t uncommon for powerful men, men who inspire fear in everyone they meet, to need an occasional moment when they are completely at the mercy of someone else. I have state senators come here from Sacramento for “discipline”. Even a Congressman once.’

Collis had rubbed his chin thoughtfully. ‘Wouldn’t Mrs Johnson give him the treatment he needs?’

Knickerbocker Jane had laughed. A laugh as dry as her sherry. ‘You still need to know a little bit more about San Francisco society, my love. Mrs Esther Harris Johnson is the daughter of Milward Harris, the chief executive of the state harbour commission. A strict, upright, churchgoing lady, not to Horace’s taste if you’re talking about sex, but one whose family connections have given Pacific Mail a tight, tight grip on the waterfront. Horace Johnson didn’t marry for love, or even for “discipline”. He comes here for that. Horace Johnson married for commerce.’

‘Well, well,’ Collis had said. Knickerbocker Jane’s worldly wisdom and complete equanimity had begun to calm him down. And for the first time since he had knelt down beside Walter West’s butchered body, he had allowed himself the callous but irresistible thought that Hannah was now a widow, respectably free, and that no divorce would be necessary.

‘Do you think I should tell Hannah?’ he had said quietly. ‘Tell her myself? About finding the body, I mean.’

Knickerbocker Jane had shrugged. ‘It’s up to you. I would have thought it more prudent to wait for someone else to bring her the bad news.’

‘Yes,’ Collis had said. The gilt clock on the mantelpiece had struck five. He had stood where he was for a moment, and then he had leaned over and kissed Knickerbocker Jane full on the mouth.

‘I’m sorry about your banker,’ he had said.

She had looked away. ‘Thank you. I’m sorry about your shopkeeper. But life goes on for the rest of us, doesn’t it?’

Collis had visited one more person before going back to Hannah at the International. Dan McReady, at the Eagle Saloon. Dan had been busy at the faro tables, relieving two bearded gold miners of seven months’ hard-earned profits, but he had asked one of the other dealers to sit in for him while he came across to the bar and talked to Collis.

‘Dan,’ Collis had said, in a quiet, confidential voice, ‘what do you know about Mr Kwang?’

Dan had knocked back a shot of whisky, coughed, and pulled a face. ‘No more than anyone, I guess. A tough son of a bitch. But a man of his word. The kind of man who knows which way the world’s going to turn.’