So they tidied up and buried the waste paper and set off together back across the levels and over the dikes to Rye. Once, at one of the narrow bridges, Penny pulled Jon's sleeve till they fell behind the others.

"What do you think of them, Jon? I think they're grand and we ought to ask them to help. You know we want allies."

"That chap David is all right," Jon agreed. "But those kids won't be any good. P'raps he'd join in without them."

"I don't think he would and I think you're wrong about the twins. They've had some adventures. Let's ask them at tea what they did and then I'll leave it to you to decide. But let's join up if we can, Jon! We haven't got much time left and I do want to find this treasure."

Jon nodded and hurried ahead to catch up with the others.

They managed to get a table in the window and the twins caused some consternation among the other customers as they settled down. After ten minutes even Jon thawed and discovered that Mary could not be ignored for long. She was much too entertaining.

"Aren't you going to tell us about those adventures of yours in Shropshire?" he asked.

And the stories they had to tell were worth waiting for and both Jon and Penny listened spellbound.

"It's funny how things have happened to us," David went on. "But they have. I don't see how anything much can happen here, but it's early days yet. Unless," he added as he caught Jon's eye, "you know of anything coming along? Do you?"

Jon looked across at Penny, who nodded slightly. Then he smiled.

"I think there is and I believe you can help us. Of course, we know you'll promise not to say anything to your parents or to anyone, won't you?"

David nodded, Mary smiled and Dickie said, "We swear."

"Well, we think we've got a clue to some treasure hidden by smugglers round Rye and Winchelsea, or even perhaps in the Dolphin; and we know that the artist woman you twins were baiting this afternoon is after it too, and she's got accomplices."

David's eyes were bright with excitement.

"Grand," he was saying. "Go on. Tell us more. This is like old times again. Oh, gosh! If only our friend Peter could be here."

"Send a telegram for her," Dickie said. "Stop everything till she comes. And the other members, too. We need them!"

"Members? What members?" Penny asked as David paid the bill and got up to go.

"We've got a secret society of our friends," he said. "That's what Dickie means."

"Well, I wish we were members," Penny said impulsively. "I'd be proud to be a member of that."

David looked at her thoughtfully for a moment but said no more as Jon went on to tell them of the connection between Miss Ballinger and Mr. Grandon and of the girl in the white mackintosh.