With a smiling bow, Patty stepped down from the platform, and taking a seat by old Mrs. Cromarty, nestled in that lady’s loving arms. The two boys made a spring for the mantel, but paused simultaneously to grasp both Patty’s hands in theirs and nearly shake her arms off. Then they left the heroine of the hour to Mabel and Mrs. Hartley and began to investigate the chimney piece.

“‘Between the fir trees and the oak’!” exclaimed Bob. “Great, isn’t it! And here for thirty-five years we Cromarty dubs have thought that meant real trees! To think it took a Yankee to tell us! Oh, Patty, Patty, we’ll take down that historic painting and put up a tablet to the honour of Saint Patricia. For you surely deserve canonisation!”

“‘Between the bedhead and the wall,’” ruminated Sinclair. “Well, here goes for finding an opening.”

Clambering up on stools, both boys examined the place where the mantel shelf touched the wall. The ornate carvings of the mantel left many interstices where coins or notes might be dropped through, yet they were by no means conspicuous enough to attract the attention of any one not looking for them.

“Crickets!” cried Bob. “There’s a jolly place for the precious poke to be located. I’m going down cellar to see if I can find traces of that mason’s work. Come on, Clair.”

The two boys flew off, and the ladies remained discussing the wonderful discovery, and examining the old chimney-piece.

“I can see it was a bedhead now,” said Mabel; “but I never suspected it before. What a splendid mantel it makes. Didn’t you ever hear its history, Grandy?”

“No, dear. It must have been put there when the house was built, I think. Though, of course, it may have been added later. But it was all before my time. I married your grandfather Cromarty and came here to live in 1855. The building and decorations then were all just as they are now, except for such additions as Marmaduke made. He may have had that mantel set up in earlier years—I don’t know. He was very fond of antique carvings.”

Back came the boys from the cellar.

“The whole chimney is bricked up,” Sinclair explained. “We couldn’t get into it without tearing it all down. And do you know what I think, Grandy? I think it would be wiser to take away the chimney-piece up here, and do our investigating from this end. Then, if we find anything, it will all be in this room, and not in the cellar, where the servants can pry about.”