It was with impatience indescribable that the members of the Antiquarian Club awaited the demolition of McCorkle's stable. Now that Alexander had enlightened them as to the approaching changes in Varick Street, the girls watched with absorbing interest the slow, gradual approach of the house-wrecking throng which had sometime before invaded the upper portion of the street. For weeks they had been passing unheeded the frenzied scene of tearing down, digging up, and general destruction that had suddenly changed peaceful Varick Street into an unsightly heap of ruin and scaffolding. It had meant nothing to them, so absorbed were they in their own affairs. And now they found, quite to their amazement, that it was going to have a very direct bearing on these same affairs!

House by house, block by block, it drew nearer. Every day that was pleasant enough for Margaret to be out she commanded Sarah to wheel her past the work of demolition, much to Sarah's disgust, who infinitely preferred the quiet, sunny, unobstructed walks of peaceful Charlton Street. Then, before turning the corner homeward, Margaret would beg to be wheeled past McCorkle's stable, at which she would gaze hard and rapturously as long as it was in sight. This also deeply annoyed and bewildered Sarah.

"Bedad!" she would exclaim impatiently, "it does beat me what ye see in that dur-rty owld rookery! 'Tis fit only fur th' scrap-heap, and ye look at it as if it was hung wid diamonds! What's got into ye these days, Margie macushla! 'Tis that quare Corinne gur-rl that has bewitched ye!"

Margaret could easily see that Sarah was very, very jealous of her new friend, so she would say nothing, but only smile her slow, mysterious little smile. "That queer Corinne girl" had indeed bewitched her, and had brought into her pain-ridden, colorless existence something worth living for! But this, of course, she could not admit to Sarah.

At last, one cold, blustery afternoon, the twins burst in with the exciting information that the house-wrecking had actually commenced on their own block, up at the King Street corner. After that the interest became concentrated and intense. And by the time the little old dormer-windowed shanty on their own corner was leveled to the ground, they had reached the tiptoe of excitement.

Fully two weeks before this McCorkle's stable had been vacated and left ready for its destruction. And since then Alexander had spent much time crawling around its foundations and examining it in every nook and cranny.

When the little building next to it came down, and the day before the stable was to have its turn, the Antiquarian Club held an important meeting, called at the request of Alexander.

"This is going to be ticklish business!" he announced; "getting at that beam, I mean. And I ain't so sure it's going to pan out all right, either. Good thing to-morrow's Saturday, so I can be on the job all day. But I've been laying my pipes pretty slick! I've got on the soft side of a lot of those workmen, and the night-watchman loves me as if I was his little nephew Willie! It's the night-watchman I'm depending on most. He's agreed to let me in there to grub around any night I want—so long as I don't do any damage. But, see here, you kids! Don't be setting your hopes on me getting at anything to-morrow, 'cause more'n likely they won't touch the foundation before next week!"

The next day saw the demolition of McCorkle's stable. It being Saturday, the Antiquarian Club was able to be present in full force (on the opposite side of the street) to see it go. Margaret's chair was wheeled by the twins and Corinne in turn. But Alexander, across the street in the danger-zone, gyrated, imp-like, up and down the sidewalk and was twenty times ousted from imminent peril by the half-indignant, half-laughing workmen.

Piece by piece the boards and bricks fell, story by story the old building came down, till at last it was level with the very sidewalk, and carts began to remove the debris. Then was visible the strange thing that Alexander had long before told them about.

"See! see!" he cried, running across to them and pointing back excitedly. "There it is! Didn't I tell you so?" And looking toward the back, they could plainly discern the queer, curved outline of the old stage, with a few cracked and tarnished bits of gilt cornice still clinging to it.

"But when are they going to reach the beams underneath?" demanded Margaret, in an excited whisper.

"Not before Monday! At least, they can't get to uncovering the ones we want before then. The rest are almost bare now."

"Oh! how can we wait till Monday!" wailed Margaret.

"I gave you the tip we might have to!" admonished Alexander. "You're entirely too light and speedy! You ought to go into the house-wrecking business yourself—then you'd see!"

The interval between Saturday and Monday seemed simply interminable to every one of the five. On Sunday, Alexander spent much time haunting the ruins, Corinne was obliged to be in her own home, Mrs. Bronson was visiting a sick friend, and Margaret and the twins, left alone, whispered together most of the day about the impending event.

"What do you suppose we'll find in that beam?" Margaret would inquire for the hundredth time.

"Probably nothing!" Bess would reply, for she was always inclined to look on the dark side of things.

"Oh, that's not possible!" Margaret would retort. "I think it may be some important papers. I don't expect there'll be gold, or jewels, or anything of that kind. But just suppose it was the sapphire signet!"

"Do you know, dear," said Jess, once, "I'd be pretty well satisfied if we even found just the hole! That would show, at least, that Alison's account was correct, and we had worked things out right, so far."

"Yes, but it wouldn't help us out any with solving the mystery," objected Margaret. "When do you suppose it will be get-at-able, anyway?"

"Alexander says he's going to be there before school in the morning, and again at noon, and in the afternoon too. He says he's almost tempted to play hookey and be there all day! But I told him Sarah and Mother would have a fit if he did! The club is to be all together here in the afternoon, and he'll come right in and tell us the minute he discovers anything."

"Wouldn't it be simply awful," moaned Margaret, "if any one got in ahead of us and looted the place in the beam!"

"Alexander doesn't think that likely," declared Jess. "I asked him about that, too, but he says it's probably so well concealed that nobody would think of such a thing—unless the beam were to be chopped up, and that won't happen for a good while yet."

So they were all forced to possess their souls in patience till Monday afternoon. Then, with fast-beating hearts, the girls gathered in the Charlton Street parlor. Alexander, of course, was not with them, and they did not expect him for some time. But, to their utter amazement, he strolled in about three-thirty, hands in his pockets, whistling "The Lass of Richmond Hill" as unconcernedly as though this were not the day of days for the Antiquarian Club!

"Good gracious, Alexander, what's wrong?" demanded Corinne.

"Wrong? Nothing at all! Everything O. K., A., number one!" he replied airily.

"But why aren't you over at the stable as you said you'd be?"

"Oh, I didn't think it worth while!" he answered indifferently, ambling over to gaze out of the window.

"But, Alec!" cried Margaret. "Have you gone back on us like this? And after all you said! And you seemed so interested, too! I just can't believe it of you!" Her great, beautiful gray eyes filled with sudden tears, and Alexander, turning from the window, observed it.

"Aw! turn off the weeps!" he exclaimed gruffly, but contritely. "Can't you all take a bit of kidding? It ain't worth while for me to be over there any more—because I've found the beam already—and explored it!"

At this astonishing revelation they sprang upon him literally in a body—all but Margaret.

"Oh, Alec! You didn't! When? Tell us all about it? What did you find? How did you do it?" The questions rained thick and fast.

"Well, just unhand me, and sit down, and I'll tell you all about it! Saturday night I was crawling round a bit after the work was all over, and only the night-watchman there. I found that the two beams on this north end were really pretty well uncovered, in spots, and what was left over them could be easily scraped off. It was mostly dirt and loose mortar. I didn't have time to do anything that night, but I gave the watchman the tip that I'd be back the next night and poke around a bit. He likes me, and he thinks I'm collecting wood to build an Indian wigwam in that vacant lot on Hudson Street. And us fellows are building one, too, so it's no lie!" Alexander, to do him justice, was scrupulously truthful.

"So I beat it out, last night, after borrowing the twins' door-key, so I wouldn't have to wake up that lallypaloozer, Sarah, when I came in. Of course I took a chance of not striking the right beam,—it might be the one at the south end, for all I knew. However, I doped out the one I thought it was, shoveled off the bricks and mortar softly, so's not to attract attention, and measured off ten feet from the west end with a tape-line. You know the kid, Alison, said the steward stood about ten feet from the wall of the house, along the beam.

"Then I opened my big-bladed pocket-knife and poked and poked and poked around it, top, bottom, and sides. But never a sign of an opening did I find. After I'd been at the job about an hour, I gave it up and scooted for the east end of the beam, and began the same thing all over. Nothing doing for about half an hour! Then all at once, my blade slipped into a crack! I gave a hard pull, and—jumping Jupiter!—there I was! The thing came open like a door on a rusty hinge, and there was a hole about a foot and a half long!

"You bet I didn't do a thing but shove my hand in and feel all around in the hole! I didn't dare even to light a match, for fear a cop might see me. Just then, all of a sudden, the watchman called out softly that the roundsman was coming and I'd better beat it while the going was good! I just had time to duck off that beam, crawl along the darkest side of the wall, and sneak out as the roundsman came along and stood talking to the watchman, as he always does, for about fifteen minutes. I got into the house all hunky,—and that's why it ain't any use for me to be there this afternoon!" he ended abruptly.

"But, Alec, what did you find? Did you find anything?" demanded the four in one breath.

Alexander nodded impressively. "Yep! I found something all right!" Then he suddenly took an object from under his coat and laid it carefully in Margaret's lap.

"I found this!"