But Sinclair’s search for the old mason in Leicester was absolutely unsuccessful. He learned that Martin Campbell had died many years ago, and had left no direct descendants. A cousin of the old mason told Sinclair all this, and said, too, that there were no books or papers or accounts of the dead man left in existence.

So Sinclair returned home, disappointed but not entirely discouraged.

“We’ll find it yet,” he said to Patty. “We have proof of a hiding-place, now we must discover it.”

“We will!” declared Patty. “But it’s so exasperating not to know whether the old mason built that ‘pocket’ indoors or out.”

“Out, I think,” said Sinclair. “It’s probably a sunken bin or vault of brick, made water-tight, and carefully concealed.”

“Yes, it’s certainly carefully concealed,” Patty agreed.

Sinclair was entitled to a fortnight’s vacation from his law studies, and he arranged to take it at this time. For now that the interest was revived, all were eager to make search all the time.

“Let’s be systematic about it,” said Bob, “and divide the estate up into sections. Then let’s examine each section in turn.”

This sounded well, but it was weary work. In the wooded land, especially, it was hopeless to look for any indicatory mark beneath the undergrowth of forty years. But each morning the four young people started out with renewed determination to keep at it, at any rate.

On rainy days they searched about the house. Having found one secret panel, they hoped for more, and the boys went about tapping the walls or carved woodwork here and there, listening for a hollow sound.

Bob and Patty went on searching the books. But though a number of old papers were found they were of no value. Incidentally, Patty was acquiring a store of information of various sorts. Though too eager in her work to sit down and read any book through, she scanned many pages here and there, and learned much that was interesting and useful. Especially did she like books that described the old castles and abbeys of England. There were many of these books, both architectural and historical, and Patty lingered over the illustrations, and let her eyes run hastily over the pages of description.

One afternoon she sat cross-legged, in Turk fashion, on the library floor, absorbed in an account of the beautiful old mansion known as “Audley End.” The description so interested her that she read on and on, and in her perusal she came to this sentence:

“There are other curious relics, among them the chair of Alexander Pope, and the carved oak head of Cromwell’s bed, converted into a chimney-piece.”

Anything in reference to the headboard of a bedstead caught Patty’s attention, and she read the paragraph over again.

“Sinclair,” she called, but he had gone elsewhere, and did not hear her.

Patty looked around at the mantel or chimney-piece in the library, but it was so evidently a part of the plan of wall decoration, that it could not possibly have been anything else.

Patty sighed. “It would have been so lovely,” she thought to herself, “if it only had been a bedhead, made into a mantel, for then that bothering old man could easily have tucked his money between it and the wall.”

And then, though Patty’s thoughts came slowly, they came surely, and she remembered that in the great hall, or living-room, the mantel was a massive affair of carved oak.

Half bewildered, Patty dropped the book, jumped up, and went to the door of the hall. No one was there, and the girl was glad of it, for if she really was on the eve of a great discovery she wanted to be alone at first.

As she entered the room, the lines came to her mind:

and she noticed that the chimney-piece stood on a sort of wide platform, which extended across that whole end of the hall. Could it be that Mr. Marmaduke had meant above this platform, calling it a stair, which ran across the great hall? For years they had taken the direction to mean “up the staircase,” and “across the corridor,” or hall which led to the bedrooms.

Slowly, almost as if afraid, Patty crossed the hall, stepped up on the platform, and examined the old chimney-piece. She couldn’t tell, positively, but surely, surely it looked as if it might once have been the headboard of an ancient bed. It certainly was different in its workmanship from the wood carving that decorated the apartment.

The top of it was well above her head, but might it not be that the old rhyme meant between this bedhead and the wall?

Here they had never looked. It must be that it was not generally known that this mantel was, or had been, a bedhead.

Still, as if in a daze, Patty went and sat in a chair facing the old chimney-piece, and wondered. She intended to call the others in a moment, but first she wanted to enjoy alone the marvel of her own discovery.

As she sat there, scrutinising every detail of the room, the lines kept repeating themselves in her brain:

“Above the stair, across the hall, Between the bedhead and the wall.”

If the secret pocket was between that bedhead and the wall, it was certainly above the stair across the hall! Why had that stair or platform been built across the hall? It was a peculiar arrangement.

This question Patty gave up, but she thought it might well have been done when the bedhead was set up there, in order to make the chimney-piece higher and so more effective.

Patty had learned something of architecture in her library browsings.

Above the high mantel was a large painting. It was a landscape and showed a beautiful bit of scenery without buildings or people. In the foreground were several distinct trees of noble proportions.

“They’re firs,” said Patty to herself, for she had become thoroughly familiar with fir trees.

And then, like a flash, through her brain came the words:

“Great treasure lieth in the poke Between the fir trees and the oak.”

The secret was revealed! Patty knew it!

Beside the bedhead evidence, it was clear to her mind that “Between the fir trees and the oak,” meant between these painted fir trees and the old carved oak mantel. Grasping the arms of her chair, she sat still a minute trying to take it all in, and then looked about for something to stand on that she might examine the top of the old mantel-shelf.

But her next quick thought was, that that was not her right. Those to whom the fortune belonged must make the investigation themselves.

“Sinclair,” called Patty, again; “Mabel, Mrs. Hartley, where are you all?”

Bob responded first, and seeing by Patty’s excited face that she had discovered something important, he went in search of the others.

At last they were all gathered in the great hall, and Patty’s sense of the dramatic proved too strong to allow her to make her announcement simply.

“People,” she said, “I have made a discovery. That is, I think I have. If I am right, the Cromarty fortune is within your grasp. If I am wrong—well, in that case, we’ll begin all over again.”

“Tell us about your new find,” said Sinclair, selecting a comfortable chair, and sitting down as if for a long session. “Is it another mason’s bill?”

Nobody minded being chaffed about searching or finding, for the subject was treated jocosely as well as seriously.

Patty stood on the platform in front of the carved oak chimney-piece, and addressed her audience, who listened, half laughing, half eager.

“What is this on which I stand?” she demanded.

“A rug,” replied Mabel, promptly.

“I mean beneath the rug?”

“The floor.”

“No, it isn’t! What is this—this construction across the room?”

“A platform,” put in Bob, willing to help her along.

“Yes. But what else could it be called? I’m in earnest.”

“A step,” suggested Sinclair.

“Yes, a step; but couldn’t it be called a stair?”

“It could be,” said Bob, “but I don’t believe it is one.”

“But suppose your erratic uncle chose to call it that.”

“Oh,” laughed Bob, “you mean the stair in the poem.”

“I do. I mean the stair across the hall.”

“What! Oh, I say, Patty, now you’re jumbling up the sense.”

“No, I’m not. I’m straightening out the sense. Suppose Mr. Marmaduke meant ‘above the stair across the hall,’ and meant this stair and this hall.”

“Yes, but go on,” said Sinclair; “next comes the bedhead.”

“That’s my discovery!” announced Patty, with what was truly forgivable triumph.

“This carved oak chimney-piece is, I have reason to believe, the headboard of some magnificent, ancient bed.”

“Patty Fairfield!” cried Sinclair, jumping up, and reaching her side with two bounds. “You’ve struck it! What a girl you are!”

“Wait a minute,” said Patty, pushing him back; “I’m entitled to a hearing. Take your seat again, sir, until I unfold the rest of the tale.”

Patty was fairly quivering with excitement. Her cheeks glowed, and her eyes shone, and her voice trembled as she went on.

Mabel, with clasped hands, just sat and looked at her. The elder ladies were plainly bewildered, and Bob was trying hard to sit still.

“I read in an old book,” Patty went on, “how somebody else used a carved headboard for a chimney-piece, and I wondered if this mightn’t be one. And it surely looks like it. And then I wondered if ‘above the stair across the hall’ mightn’t mean this platform across this hall. And I think it does. But that’s not all. My really important discovery is this.”

Patty’s voice had sunk to a thrilling whisper, and she addressed herself to Mrs. Cromarty, as she continued.

“I think the other rhyme, the one that says the fortune is concealed ‘between the fir trees and the oak,’ refers to this same place, and means between the painting of fir trees, which hangs over the mantel, and—the oak mantel itself!”

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.”

“I quite agree with you,” said Mrs. Cromarty, “and I put the whole matter in your hands. You and Robert are the sons of the house, and it is your right to manage its affairs.”

“Then I say, tear it down at once,” cried Bob. “We needn’t damage the carving itself, and all that we break away of plaster or inner woodwork can easily be repaired, whatever our success may be.”

“Shall we begin now?” asked Sinclair, doubtfully. He was not so impetuous as Bob, and would have been quite willing to study over the matter first.

“Yes, indeed!” cried his impatient brother. “I’m not going to waste a minute. I’m glad I’m a bit of a carpenter. Though not an expert, I can tear down if I can’t build up.”

“But we must take it down carefully,” said Sinclair. “These screws must come out first.” But Bob had already gone for tools, and soon returned with screw-drivers, chisels, gimlets, and all the paraphernalia of a carpenter’s well-appointed tool-chest.

“Here goes!” he cried, as he put the big screw-driver in the first screw. “Good luck to the Cromartys and three cheers for Uncle Marmaduke and Patty Fairfield!”