“It occurred to me” – Arthur leaned sideways and very carefully dusted the ash of his cigar into a silver tray on the library table – “it occurred to me that you might care to give me proof and evidence of your good feeling.”

“I don’t understand you,” said Gilder.

Arthur hesitated.

“I wondered whether you would write me a letter, to the effect that you are lending me this very large sum. You see, Gilder, although you plan to marry my sister, I am vain enough to wish that it should not be regarded as a gift or the price – the price of her marriage – but as a loan to me.” He laughed. “Don’t look at me like that, my dear fellow. I am not asking you for money, I am seeking a salve to my conscience. I don’t want people to say, ‘Leslie Gine was sold for fifty thousand pounds.’ I want to produce evidence that you did no more than lend me the money.”

A slow smile dawned on Gilder’s face.

“There’s no objection to that,” he said. “I’ll give it to you now, if you like. Do you mind if I address you as ‘Dear – Arthur’?”

“Charmed,” murmured Arthur.

“One has to keep up the pretence of friendliness,” said Gilder as he wrote rapidly; “and really I’ve no strong feeling against you, Gine. You’ve been a useful man to me.”

“Damned useful,” said Arthur, without heat.

The man blotted the letter, brought it across, and Arthur Gine read it carefully.

“Thank you,” he said, folded and put it into his pocket. “You may think I’m rather weak – which of course I am – and vain: I’m afraid there’s no doubt about that! You will hear from Leslie when the mailbox is cleared – that is, if the letters are intact. There is some suspicion that our friend Thomas, baffled in his attempt to open the box, and inspired with that instinct for destruction which is one of the characteristics of the unbalanced criminal, threw in a couple of lighted matches. I had the curiosity to smell at the letter slot, and I think it is very likely that the police theory is correct.”

He rose, took up his silk hat and stifled a yawn.

“We’ve had rather an exciting night in my part of the world. You’ve probably read all about it in the newspapers?”

“Has Lord Chelford been found?”

Arthur shook his head.

“Not at the time I left,” he said. “Unfortunately Leslie was a witness, if not to the murder, to the finding of the first body. The poor little girl was knocked all to pieces. Don’t bother her for a day or two – do you mind?”

He held out his hand and Gilder took the soft, cool palm in his.

“I think we shall get on together, Gine.”