“Did he tell you that?” she said, with a little catch in her voice. “I hope you don’t think, Mr Gilder, that I’ve thrown myself at his head? That I wouldn’t do for the best man in the world.” She looked at him thoughtfully, and added: “Old or young. I trust Arthur as a gentleman to fulfil any promise he has made. I am going to do something for him that will make all the difference in the world–”

“When is he going to marry you? After the treasure is discovered, I suppose?”

She nodded.

“He will have to marry me then,” she said.

“I realise that. You’re a girl that has to make her way in the world without influence, and possibly without friends.” Mr Gilder knew he was on the right tack here. “He can offer you a position and you can offer him money. After all, that is exactly what his sister is doing, and nobody thinks any worse of her for that.”

“Exactly,” murmured Miss Wenner, who had never seen the matter in that light before.

“The point I want to make is this,” he went on. “What bond has he given you?”

“His word of honour,” said Miss Wenner dramatically.

“I daresay. But what valuable bond has he given you?”

“I’ll show you.”

She went into the next room, which was evidently her bedroom, and, returning with her bag, placed it on her knee, opened the flap and took out, amongst other things, a slip of paper, which she passed across to Mr Gilder. He read it at a glance, noted the careful emendation which Arthur had made, and passed it back.

“That is valueless,” he said, and her face fell. “What is to prevent his going to Chelford and striking a bargain with him? Where do you come in then? Besides, this is what is known in law as a promise under duress – that is to say, under compulsion. If he is acting in the interests of his client, he can plead that he had to make this promise in order to secure information which you were illegally withholding.”

She stared at him.

“It’s not illegal to know and not to tell?”

He nodded.

“To know of the existence of hidden treasure and to withhold your information is a crime in some countries, and I daresay it is in England. But that’s beside the point. Where do you come in, Miss Wenner?”

She bit her lip thoughtfully.

“I never saw it in that way,” she confessed. “What can I do, Mr Gilder?”

“Get him to marry you first.” He felt inclined to offer the obvious solution, but changed his mind. Mary Wenner married would be a useless ally.