And the unexpected happened sooner, much sooner, than Margaret would even have dared to dream. Something did "turn up"! But like many adventures, it came clothed in the guise of quite an ordinary, every day affair, and there was little about its beginning to suggest the remotest idea of anything startling. To be exact, it was simply that about a week after the beginning of their acquaintance the twins came home one day with the announcement that their new friend, Corinne, had expressed a decided wish to call and make Margaret's acquaintance, and that they had invited her for the following day. At first Margaret had protested strongly:

"Oh, no, girls! I can't see her. You know I never see any strangers. It's awfully nice of her. But—but I wouldn't know what to say to any one I didn't know very well. Do thank her for me, but—"

"Nonsense!" cried Bess, decidedly. "It'll do you good to see some one beside just ourselves. Mother thinks so too. And you'll like her, I know. I couldn't tell her she mustn't come, anyway! It wouldn't be polite!" And that clinched the argument.

In reality, it had seemed quite wonderful to Margaret that this interesting new friend of her sisters could possibly care to become acquainted with her, and she felt grateful for the pleasant attention. But with the unconquerable shyness of a secluded invalid she shrank from the meeting, all her longing for something new and exciting to happen being temporarily forgotten. And then the day arrived.

"Ye'll be after havin' company, this afternoon, Margie mavourneen, so I suppose ye'll be wantin' a little snack about half-past four?" Sarah had just wheeled Margaret into the front parlor by the window, raised the shades a trifle, and tucked her idol securely and cozily into her chair.

"Oh, yes, Sarah! Do have hot chocolate and those lovely drop-cakes you made this morning!"

"Who's the gur-rl that's comin', anyway? Shure it's a strange thing for you to be seein' any one!" Sarah exclaimed jealously as she turned to leave the room.

"Oh, some one named Corinne Cameron. She's a nice girl. The twins like her," replied Margaret, with assumed indifference. Not for worlds would she have allowed Sarah to read her real feelings on the subject.

"Huh!" was Sarah's only reply as she handed Margaret her book and lumbered heavily downstairs to the kitchen, while the invalid settled herself to wait for the arrival of her twin sisters and their "queer" new friend. It was only two o'clock and she couldn't possibly expect them before three or a quarter past. The time loomed long and interminable before her. First she tried to read, but even the beloved "Little Women" failed to interest her. So she rested her elbow on the arm of her chair, and, chin in hand, stared out of the window across the street at a squat little dormer-windowed house directly opposite.

Would she really, she wondered, like the girl who was coming that day? The occasion was certainly an unusual one in her uneventful life, for she saw, as a rule, almost no one outside of her own family, except the doctor. From the time she was a small baby she had suffered with an affection of the spine, and the physicians could hold out no hope that she would ever be anything but an invalid. Ever since she had grown too large to be carried about, she had spent her waking hours in this invalid-chair.

Of the outside world she saw little save the view from the parlor windows, and what passed before her each sunny day during the short hour that Sarah pushed her in her chair up and down the block. But Margaret was singularly loving and sweet-tempered, and most of the time successfully hid the pain and weariness she suffered, both in body and mind. Few realized, except the faithful Sarah, what bodily misery she often endured; and none could appreciate the unconquerable shyness that kept her from all companionship with girls of her own age, excepting that of her sisters.

Margaret envied nothing more heartily than the ability to join in the athletic sports of the robust twins. She yearned above all things to play basket-ball and wield a tennis-racket. And because such things were to be forever impossible to her, she felt that she could be of no earthly interest to her sisters' equally athletic comrades, so she shyly refused to meet any of them. But this new girl was obviously "different." Margaret felt that perhaps she would understand, that they would find much of common interest to talk about. For Margaret, too, loved books,—loved them with the passionate delight that only confirmed invalids can feel for the printed magic that takes them out of themselves and makes them forget their bodily ills. She read voraciously everything that came her way. Beside that, she had long ago insisted on studying with the twins. She kept pace with them through all their school work and often outstripped them in the quickness of her comprehension. And the twins were immensely proud of her attainments.

The home life of the Bronsons was a pleasant one, but rather different in many ways from that of ordinary families. Their father had died when Margaret was a baby. Their mother was the busy, worried, overworked director of a large French dressmaking establishment on Fifth Avenue. By her earnings she supported her family in moderate comfort and maintained the little house in Charlton Street, which had always been their home. She went away to business early every morning, and often did not arrive home till late in the evening, especially in the "rush" seasons. Thus she saw little of her children except on Sundays, and then she was usually too tired to enjoy their company, though she loved them devotedly.

It was big, loyal Sarah McKinstry who really ran and directed the household. She had lived with the family ever since Mrs. Bronson had come to the Charlton Street house, a bride, and considered it her own. Little, frail, ailing Margaret she adored with a passionate and jealous devotion. Margaret never teased her, as did the twins, and many a weary night had she spent sitting up with the little sufferer when the pain was worse than usual. Her sharp tongue she used on the others unsparingly, but never on the delicate child in the invalid-chair. Nevertheless, as a matter of fact, she was really devoted to them all. And though they, perhaps, never expressed it in quite that way, they knew that the heart of Sarah McKinstry was as a precious jewel in a setting of cast-iron.

So on this sunny afternoon sat Margaret in her window, wondering much about the coming visit,—wondering for the hundredth time if she would really like this queer Corinne Cameron, and—which was even more important—would she be liked in return.

The clock on the mantel chimed three, and Margaret began to crane her neck in order to see as far down the street as possible. They would come from the Varick Street end of the block, she knew, because they always walked down that way, in preference to the shorter but not so pleasant route through Macdougal Street.

At three-fifteen precisely they swung into view. The twins, who looked very much alike, were walking one on each side of a tall girl, who topped them by almost a head. Margaret gave a little gasp and leaned far out of her chair. In one swift glance she scanned the new acquaintance, as the three came abreast of the house.

"Oh, I'm going to like her—surely!" she whispered, as she waved in answer to the triple salute. Then she drew back suddenly behind the curtains in a new access of shyness, now that the encounter was really so close.

But if Margaret had any lingering doubts on the subject, they were quickly dispelled in the first half-hour with the "queer" girl. Corinne broke the ice at once after her introduction to the little invalid.

"What a dear, fascinating house you live in!" she began, gazing about the parlor with her dreamy, far-away look. "That carved marble mantel is just fine, and so are the pillars between the rooms, and all this white paneling."

The twins stared at each other and then at Margaret.

"Mercy! Do you think so?" cried Bess. "Why, we've always thought it the horridest, old-fashioned place—"

"That's just what I mean," interrupted Corinne. "It is old-fashioned, and that's why it's so delightful!"

"Oh, we forgot that you like old things!" laughed Bess. "Well, this is just a little, old, shabby rookery, and not a single interesting thing about it. You don't know how we've longed to move into a lovely new apartment—like the one you live in, for instance,—and have all the up-to-date fixings and everything."

"Well, I'd give a lot to change with you!" replied Corinne. "I hate apartments! I've lived in one all my life, and I've always just dreamed of living in a dear old house like this that was built fifty or a hundred years ago. Think of all the things that must have happened in it, and all the history it's seen!—Nobody ever heard of anything historical about an apartment-house!"

Margaret, who hadn't said a word all this time, leaned forward now with shining eyes and demanded:

"But—Corinne—" (she hesitated just a little over the unaccustomed name) "what can you possibly see about this place that's interesting? We've always thought it just as ordinary as—as ordinary could be,—when we've thought about it at all!" And now Corinne was in her element.

"Why, think of it!" she exclaimed. "Think what stories there must be about this house—or any old house! Think what strange things may have happened in it! Think what history it's seen! Think what mysteries there may be about it—if we only knew them! Just imagine what scenes people may have looked at out of those darling little dormer-windows, or what famous generals may have leaned against this white-pillared mantel and talked of their battles, or what traitors may have sat in this parlor and laid plots, or what secret letters may be hidden behind the woodwork in that funny little cater-cornered closet over there, or—"

She stopped suddenly from sheer lack of breath. Her three listeners were staring at her spellbound. Even the less impressionable twins were devouring her words in wide-eyed wonder.

As for Margaret, she was tingling to her finger-tips with a strange excitement. A whole new vista of wonderful things had suddenly been opened to her. She looked about on what she had always considered her perfectly ordinary, commonplace home, and her very scalp prickled to think of the many-sided mysteries its walls might contain. She felt a sudden wild desire to get to the cater-cornered closet Corinne had mentioned (though she knew it contained nothing more exciting than Sarah's dusters and some dilapidated books), rip out its white woodwork and search frantically for hidden documents. Instead, she leaned back in her chair with a long sigh, and remarked:

"Well, you are a wonder, Corinne! You've given me something new to think of. From now on, this house will always be as interesting to me as a story!"

Corinne nodded, but only said, "I know!"

Suddenly Jess sat up with a start and exclaimed:

"Oh, by the way, Corinne, as you're so interested in old things, I wonder if you'd like to see the spinning-wheel we've got up in the attic. Mother says it belonged to her grandmother in New England more than a hundred years ago!"

"Have you actually an attic?" cried Corinne, joyfully. "Oh, do let me see it—that is, if it won't be inconvenient! Actually, girls, I've never been in a real attic in my life! And I'd love to see the spinning-wheel, too."

"Well, come right along with me," said Jess, "and we'll see it while the daylight lasts. I suppose it isn't the same kind of an attic you'd find in a big old farmhouse, but it's the open space over the top floor that we've always used as an attic and storeroom, except the back part, which is finished off into a room that Sarah uses. She's our maid,—or rather, our housekeeper, and we'd better not let her catch us up there, because she's awfully particular how she keeps the attic, and never allows us to go up and disturb things."

So Jess escorted the antique-loving Corinne to the exploration of the attic, while Bess remained downstairs to keep Margaret company.

"Well?" she questioned, turning to her younger sister as soon as the others were out of ear-shot. She knew that no further explanation of her question was necessary.

"Oh, she's simply wonderful!" exclaimed Margaret, in a half-whisper. "I rather expected I'd like her, but I never dreamed she'd be as interesting as this. And she thinks the same way I do about a lot of things."

"But isn't she queer!" marveled Bess. "Actually, on the way walking down here this afternoon, I thought we'd never be able to drag her past some of the old, rickety places on Varick Street. She'd stand in front of each one and rave about it till we really began to attract the notice of people passing. But she didn't care! You'd have thought we were sight-seeing in Europe! And she was worst of all in front of that ramshackle old place on the corner of Carmine Street, that has a whole piece of the side cut off, apparently, and the front door stuck in that funny angle. True as you live, she got out a blank-book and pencil and stood there sketching it! (You know, she draws beautifully.) Said she wanted to show it to her father! I didn't think or care anything about that kind of talk then; but do you know, what she's said here this afternoon actually makes me feel kind of interested in it all! I seem to see a lot in these old things that I didn't before."

Bess gazed about the parlor again with speculative eyes, and added: "Now, that old cupboard in the corner, for instance," when they were both startled by a loud crash from upstairs.

"Gracious!—what was that?" she exclaimed, and ran out to the foot of the stairs to listen. But as there were no further alarming noises, she soon came back.

"I guess it wasn't anything serious, but I hope nothing's broken or disturbed, or Sarah'll have a fit!"

Five minutes later, Corinne and Jess came tearing down the stairs, breathless and excited, the latter carrying something in her hand.

"Did you hear that bang?" cried Jess. "It was an accident—I'll tell you about it—but we made the most wonderful discovery—you can never guess what!" she was panting for breath and stopped short at this point.

"Tell me! Tell me quick!" begged Margaret, almost wriggling out of her chair in her excitement.

"Here it is!" Corinne, equally breathless, took up the tale. "We brought it down—" At this moment there came the sound of heavy, thumping steps on the basement stairs, and Jess, running to the bookcase, hastily thrust something far behind a row of books.

"Sarah's coming!" she warned. "I've hid it. She mustn't guess what we've been up to, or she'd spoil everything!" She laid a warning finger on her lips as Sarah tramped massively into the parlor bearing a daintily spread tray.

"I hur-rd a tur-rible bangin' jest now!" she remarked suspiciously as she set it down. Then turning her eyes on the twins: "What might the pair of ye have been up to?"

"Oh, nothing, Sarah!" Jess replied sweetly. "I went up to the attic for a moment, and something fell while I was pulling it out. But there wasn't any damage done," she hastened on reassuringly, "and I put it right back!"

"I've warned ye to keep out of that attic!" grumbled Sarah, arranging the chocolate-cups. "Something always happens when ye go there. From now on, I think I'll be lockin' it up!"

"My gracious!" thought Margaret, boiling inwardly with impatience. "I do believe this is an adventure, at last! Will Sarah ever get out of this room so that I can hear all about it!"