If Corinne thought to create a sensation by her last disclosure, she
was gratified beyond her wildest expectations. It was not, however,
what they all _said_ (for they were rendered literally speechless by
surprise), but the way they _looked_ that caused her to go almost
into hysterics of laughter. If she had informed them that there was a
lighted bomb about to go off in the cellar, they could not have assumed
more open-mouthed, startled expressions!

“Oh, don’t look so stunned!” she panted, at length, weak with laughter.
“It won’t hurt you!”

“But—b-but—” stammered Margaret, and at last brought out the eternal
question, “how—how do you know?”

“The way I know is this, and in order to explain it, I might as
well tell you the whole history of the place. It won’t take long,
and it will make you understand better. We know how Richmond Hill
began, so I won’t go over that. After the battle of Long Island and
Washington’s retreat from New York, we don’t hear a thing about it
till the end of the war. About that time it was the headquarters of
the British general, Sir Guy Carleton. After the war, when Washington
became President and New York the capital, Richmond Hill was taken by
Vice-President John Adams as his residence till the capital was removed
to Washington.

“Then Aaron Burr took it, lived there a number of years, improved the
place a lot, and made the grounds very beautiful. I must tell you right
now that the place was a _hill_ at that time, about a hundred feet
high, and had a fine view over the Hudson. The river was nearer too,
just a few feet beyond Greenwich Street. That hardly seems possible,
for it’s blocks farther off now. But in later years they filled it in
and made a lot more space to build on, and that has moved the river
banks farther away. Well, Burr lived here with his wife and a lovely
little daughter, Theodosia, till after he killed Hamilton in the duel.
Then he had to give the place up, and it was sold.

“After that, a number of different people lived there till 1817. Then
the city began to reach up this way, and they decided to put regular
streets through here and make city blocks. Of course they couldn’t
leave a high hill like that standing, so they leveled it and lowered
the house gradually to the street, and it stood somewhere right about
here. I can’t make out the _very_ spot, for some books say it was on
the north side of Charlton Street, and others, on the south side. And
one even said it faced on Varick Street. But anyway, right near this
spot it stood; and as no one seemed to want such a big place for a
residence any more, it became a sort of hotel or tavern.

“Then, some one else bought it and turned it into a theater, and for
several years it was called the Richmond Hill Theater. But it wasn’t
very successful, so after a while it was sold again, and this time
became a menagerie and circus. Later it was turned into a tavern
again. But at last, in 1849, it was so old and rickety that they tore
it down and put up these nice little houses over the place where it
stood. That’s all there is about it. Now are you convinced that I
wasn’t crazy?”

“It seems too wonderful to be true!” sighed Margaret. “To think we’re
living right on the spot where all these strange things happened to
Alison! I can scarcely believe I’m not asleep and dreaming all this.
But, oh, there are so many questions I want to ask! For instance, I
can’t yet understand how it was that if Madame Mortier was a Tory,
Washington could have his headquarters at her house. Couldn’t she have
forbidden it?”

“Why, it seems to be this way,” answered Corinne. “In war time then,
as well as now, the army that was occupying a city could do about as
it pleased—used all the houses and food and so forth that it felt
inclined to, whether the things belonged to the enemy or not. Sometimes
they would pay the people for them, and sometimes they didn’t—just
_took_ them. I suppose Washington had to have headquarters out of town
for some reason, and the only available place was Richmond Hill. He was
probably sorry enough to cause Madame Mortier any inconvenience, and
no doubt he offered her all reasonable compensation. For I read in one
book that Washington made it a rule that this should be done whenever
it was necessary to use any one’s house or goods. If she didn’t like
it, he couldn’t help that. Matters were too serious for him to quibble
about such things.

“That’s my only explanation of your question, Margaret. But what
puzzles me even more is how did Alison come to be there at all? Who was
she? Why did she leave Bermuda, and what did she do before she left it
that caused her to be under suspicion?”

As no one could throw any light on these mysteries, they all remained
silent a moment. Suddenly Jess, who had been turning the pages of the
blank-book in which Margaret had copied the journal, broke out with
this demand:

“What _I’d_ like to know is the explanation of this: ‘A strange thing
happened last night. At midnight I awoke. I heard confused sounds on
the road without—carts creaking by, men shouting, women crying, and
babies screaming.’ Now what do you suppose it was all about?”

“I think I can explain that,” answered Corinne, who seemed literally
saturated with historical information since her recent researches. “In
February of 1776, while Washington was still besieging the British at
Boston, he sent General Lee down to New York to begin fortifying it.
Lee and his forces arrived in the city on the very day that Sir Henry
Clinton, the British commander, sailed into the harbor with a fleet of
vessels. Well, the city just about went into a panic, for every one
was certain there would be a big battle right off! And the histories
say just what Alison did—that they all began to pack up and move out
of the way as quick as they could, and all night the roads were filled
with carts, and coaches, and crying women and children. Every one was
scared to death! It proved to be a false alarm, for Clinton sailed
right off again, and Lee only tended to the business of fortifying.

“But, you notice, Alison says that was when all the servants ran away
but two, and Madame Mortier got sick and went to bed. She must have
been sick a long time, for Washington didn’t get there till April or
May, and she was still in bed then. Perhaps she was quite an old lady
and had had a severe shock. Maybe she was delicate anyway. And she
evidently must have heard that her house was to be made use of, because
she sent for Alison and warned her about it, and that she wasn’t to
have any communication with the rebels. Madame Mortier must have been a

“But tell us more about the plot!” cried Margaret. “That’s the main
thing, after all. How did they intend to kill Washington?”

[Illustration: “Madame Mortier warned Allison that she wasn’t to have
any communication with the rebels”]

“Why, I read in one book that some one was to put poison in a dish
of peas, but somehow Washington was warned about it ahead of time
and didn’t eat them, of course. But he learned all about the plot,
and he had a lot of the conspirators arrested. One of them was
courtmartialed and hanged, as a proof that such performances didn’t
pay. I’m glad _somebody_ was punished for trying to do such an
abominable thing, anyway!”

“Well, one thing I’m convinced of!” declared Bess. “That wicked old
steward had a lot to do with the scheme. Don’t you think so?”

“He certainly must have,” agreed Corinne. “But what do you suppose he
was doing down there in the cellar when Alison saw him that night, and
why did he hide things in that place in the beam? And what part did
Alison take in the plot, anyway? Isn’t it simply distracting that her
journal is torn off right there! And where _can_ the rest of it be, and
why was it torn at all? And why was this part saved so carefully? And
what became of the sapphire signet? Seems to me as though I’d go crazy
with all these unanswered questions pounding away in my brain!”

Nobody having any solutions to offer, again they all sat quietly for a
while, till Margaret’s eye happened to light on the pile of books that
Corinne had laid on the floor.

“What are those, Corinne?”

“Oh, they are some books on New York City history that I got out of the
library to read up. Each one has something about Richmond Hill in it.
And this one even has a picture of the house. See! here it is.”

They all crowded around her to look. “What a fine-looking place!” was
the general comment. And Bess added:

“Does it seem possible that this shabby old neighborhood ever looked
like that delightful country-place!”

“It was the most beautiful residence anywhere around New York for
a long while,” said Corinne. “The grounds were fine too, and the
big gateway to the estate was right where the corner of Spring and
Macdougal streets is now. I thought you might like to read these books,
Margaret, so I brought them for you. But oh, girls!” she ended; “right
here and now I take the solemn determination that I will clear up this
mystery if it takes me the rest of my life! I’ll never be content till
I know the explanation of it all. And, Margaret, I want you, if you
will, to make a copy of the journal for me—not the cipher, but the
plain English—so that I can refer to it whenever I want. Will you?”

“Indeed I will!” agreed Margaret. “We’ll all help you in every way
we can. And here’s something else I’ve decided on. I’m going to
change your office in this Antiquarian Club, Corinne, from just plain
secretary to Chief Investigator!”

The Antiquarian Club continued to meet two or three times a week,
but for some time the meetings were not enlivened with any further
discoveries. Corinne grew quieter and more uncommunicative, Margaret
restless and discontented. And as for the twins, now that the
excitement had subsided and nothing further on that order appeared
to be forthcoming, they became frankly bored with the proceedings of
their society and were claimed once more by their basket-ball and
tennis-playing companions.

Several afternoons Corinne went alone to the Charlton Street house and
sat long with Margaret, going over and over the old account-book story.
For neither of them did interest in the matter ever wane. And even
though they appeared to have reached an insurmountable barrier, it
did not utterly discourage them. The mystery was always there, and the
unsolved riddle proved a constant lure.

Then one day Corinne came in, accompanied by the twins, and all seemed
in rather high spirits.

“What’s the news?” demanded Margaret at once. “Have you discovered
something, Corinne?”

“Yes, I have. And while it may not be of any _great_ help, at least
it’s another link in the chain.”

The twins, once more condescending to interest themselves in the
affair, exclaimed: “Do tell us about it! We cut a basket-ball match to
come home this afternoon!”

“Well, as I said, it isn’t much, but it’s something. Yesterday I was
up at the Forty-second Street Library, browsing around among the old
reference-books on New York City history, when I suddenly came across
this. You remember, several times Alison spoke about the housekeeper,
‘Mistress Phœbe’? Well, I’ve found out who _she_ is!”

“You have!” they chorused.

“Yes, and I guess it’s positive, for two books mention it. She was
Phœbe Fraunces, the daughter of Sam Fraunces who kept the famous
‘Fraunces’ Tavern.’ The building, by the way, is still in existence
down on Pearl and Broad Streets. It has been restored to look just the
way it used to, and is the headquarters of the Sons of the Revolution.
Sam Fraunces was a fine man and a great admirer of Washington—”

“Yes, Alison said so!” interposed Margaret, half under breath.

“—and he was afterward the household steward for Washington when he
lived in New York as President. One book says Phœbe played quite a part
in the plot—preventing it, that is! That’s all I found out, but it’s

“It certainly is!” assented Bess, after a moment’s thought, “and it’s
just one more proof that we’re on the right track. But still I don’t
see that it helps very much in finding out what became of Alison, or
anything about her!”

“No, it doesn’t!” agreed Corinne ruefully. “And that’s just where
it’s so disappointing. But there’s this about it. In a puzzle like
this, every little bit helps along. Sometimes, what really doesn’t
seem to amount to anything at all, leads at last to the most important
discovery. For instance, that song—’The Lass of Richmond Hill.’ _That_
didn’t impress us so much when we came across it, yet it really led to
all the discoveries we’ve made. I propose that this afternoon we go
over the whole thing again, just as carefully as we can, and see if
there isn’t some little clue that we _may_ have constantly overlooked.
Of course, I’ve done that by myself dozens of times, and so has
Margaret. But four heads are better than one! Who knows but _this_ time
we may light on the very thing?”

She was so hopeful and enthusiastic about it that they all settled down
to the work, reading over the old diary very slowly and discussing
every point that seemed to offer the least suggestion of a clue. They
had reached the entry which announced Washington’s arrival, and were
hotly debating the question whether or not Madame Mortier could be
concerned in the plot against him, when suddenly they were electrified
by hearing the loud crow of a rooster, coming apparently from the
darkness at the far end of the room. (They had been talking and reading
by the light of the open fire only.) Every one jumped, and Margaret
caught her hand to her heart. But Bess instantly recovered herself,
darted across the room, dived behind the curtains, and returned
dragging into the circle a grinning, giggling small boy.

“It’s Alexander, of course!” was her brief remark. Her captive was
certainly an extraordinary-looking youngster! Wiry, and undersized
for his age (he was thirteen), he possessed a snub-nose, a shock of
brilliant red hair, and a quantity of freckles that literally “snowed
under” his grinning countenance. His appearance was rendered all the
more remarkable by the fact that he had cut a series of holes in an
old, round, soft hat, and his brilliant hair stuck straight up through
these in astonishing red bunches. Not one whit did he seem to resent
the publicity into which his recent exploit had brought him! Rather did
he appear to glory in the situation.

“Aren’t you ashamed to be eavesdropping behind the curtains?” demanded
Bess, shaking him by his collar, of which she still retained her hold.

Alexander straightened himself and made this cryptic reply:

“I don’t get yer! But if yer mean piking off this chinning
contest,—no, I ain’t!”

At the foregoing remarkable explosion of slang, Corinne suddenly went
off into a peal of laughter.

“Oh, Alexander, you’re _rich_!” she exclaimed. “I’m glad to make your
acquaintance. Teach me some of that, will you!”

The boy turned to her with an appreciative and understanding twinkle in
his eye: “Sure thing! I’ll put you wise, any old time!”

But Jess suddenly broke into this exchange of amenities. “Do you girls
realize what has happened? Alexander Corwin has been listening to all
the proceedings of our secret society, and now he knows just as much as
we do! Oh, I could _scalp_ you!” she ended, making a sudden dart at her
cousin, who, though still in the grasp of Bess, ducked and evaded her.
There had been unceasing warfare between Alexander and the twins ever
since he came to reside with them. He teased them unmercifully, and
they sought frantically, and always in vain, to retaliate. There seemed
nothing they could devise that affected him in the slightest. This, the
most recent outrage, constituted to them, therefore, the last straw!
Suddenly Margaret intervened:

“Wait a minute! Maybe Alec wasn’t _really_ trying to overhear what we
said. Perhaps he only meant to give us a scare. How about it, Alec?”

“You got the right dope!” affirmed the young rascal. “D’ye think I’d
waste my valuable time listening to the chatter of a lot of Sadies? Nix
on that! I just crept in there to give the glad whoop and raise you out
of your chairs!”

Alexander never teased Margaret. Her pathetic confinement to her
invalid-chair appealed to his rowdy little soul, and between them there
had always been an unspoken compact of peace.

“But how much _did_ you hear?” reiterated Jess.

“Well, I couldn’t help getting wise to _some_!” admitted Alexander
wickedly, conscious that this same admission was gall and wormwood to
the souls of the twins. “Heard a lot of stuff about finding a book
in our attic, and George Washington, and a swell guy called Madame
something-or-other and some kind of a dinky sapphire thing, and a kid
called Alison. Say! she must have been _some_ girl! But, gosh!—you
needn’t think I _wanted_ to hear it! I was only waiting for the chance
to give you the merry ha-ha!”

Dismay fell once more on the circle. Bess had now released him, and he
stood upright, jammed his hands in his pockets, and grinned on them
with a curious mixture of triumph, defiance, and pure impishness. It
was Corinne who became suddenly inspired with a brilliant idea.

“Look here, girls! I vote that we make Alexander a member of the club!
What do you say?”

“Gee! I don’t _want_ to be!” exclaimed the boy in a panic, making a
sudden dive to escape.

“Oh, yes you would, if you knew all about it! Wouldn’t he, Margaret?
It’s just the kind of thing a boy would go crazy about. There’s so much
_adventure_ in it!”

At the word “adventure,” Alexander pricked up his ears.

“What’s a lot of _girls_ got to do with adventures?” he inquired

“Just wait till you hear!” declared Corinne, and Margaret seconded her

“Oh, dear, Alec, you’ll just go wild over this! And it ought to have a
boy in it, too! Oughtn’t it, girls?” But the twins remained obdurate.
To allow their declared enemy to share their most cherished secret
seemed to them the height of madness. But while Margaret was reasoning
with Alexander, Corinne whispered to them:

“You’d better do it, I tell you! He knows too much already, and you
don’t know but what he might give the whole thing away to Sarah
sometime!” And this final argument brought them speedily round to her
point of view.

“All right!” they agreed. “Alexander, you can become a member of our
secret society if you want to, and Corinne will tell you all about it.”

And Alexander, his curiosity now thoroughly aroused, offered no further
objection to the honor thus thrust upon him.

Corinne undertook to explain the whole matter to him, showed him
their discovery, explained how they had deciphered the code, and then
proceeded to read him the translation. His pat, slangy comments on it
often moved her to laughter, and when it came to the mention of the
song, he immediately wanted to hear it, for—it was Alexander’s chief
merit—he loved music with the appreciation of a born musician. It
happened that among the books Corinne had brought Margaret was the
collection of old songs, containing the one in question. She hunted
this up now, and, going to the piano, played it over for him, while he
stood at her side whistling the air.

“Say, I like that!” he commented when she had finished. “That’s a great
old tune! The words are a back-number of course, but they go with it
fine!” He hummed it over again.

“Isn’t it queer!” exclaimed Corinne. “Alexander is the only one who has
exhibited the least interest in learning or even _hearing_ that song!”

After this intermission, the story proceeded, the boy growing more and
more absorbed with every word. But when it came to the disclosure that
Richmond Hill had stood just about where they were now sitting, he
leaped to his feet with a whoop.

“Say! Wouldn’t that jolt you! Gee! I didn’t have any hunch that you
girls had a thing like _this_ up your sleeve!” Then, with snapping
eyes, he settled down to hear the remainder of the tale. When Corinne
had finished, he sat cross-legged before the fire for several minutes,
chewing meditatively the cap he had riddled with air-holes.

So long was he silent, that Margaret exclaimed, finally: “Well?” Then
he got up, stretched his legs, and inquired: “When you going to have
the next meeting of this joint?”

“The day after to-morrow,” answered Margaret, who was disappointed that
after all he did not seem to have any interested comments to make. “Why?”

“Because,” he answered in his remarkable jargon of slang, “you can ring
me in on the fest, and—I _may_ have a new piece of dope!”

When the meaning of this remark had dawned on them, they all demanded
eagerly: “What? What? Can’t you tell us, Alec?”

“Nothing doing—till the day after to-morrow!” he called back as he
made a hasty exit down the hall.

And after his departure they all agreed that they had possibly done
a rather good day’s work in admitting the rowdy Alexander to the
Antiquarian Club!

Two afternoons later all the girls were gathered in the parlor promptly
at three, but Alexander had not yet put in an appearance. He attended
the public school, which did not dismiss as early as high school, and
he would probably be at least three quarters of an hour late, as he
was usually kept in for misbehavior. During his absence, the girls
discussed him eagerly.

“Do you know,” vouchsafed Corinne, “I think he is the _cleverest_
little rascal, and so comical that I want to laugh whenever I look at
him! How is it I’ve never seen him before?”

“Why, the explanation is,” answered Bess, “that he never stays in the
house afternoons if he can possibly help it. He’s always out running
the streets or playing baseball in the vacant lots. But the other
day it was cold and damp, and Sarah discovered that he had a bad sore
throat and insisted that he stay indoors. He’s rather afraid of Sarah,
though he does tease her frightfully. That’s why he was around trying
hard to annoy us—he hadn’t anything else to do!”

“Well, he’s a little trump, anyway!” insisted Corinne. “And did you
ever hear such a glorious collection of slang!”

“Isn’t it _awful_!” sighed Margaret. “Mother is terribly worried about
him and the way he talks. And yet she can’t help laughing, herself,
sometimes, at the funny things he says. Really, he often seems to be
speaking in some foreign language that I can’t understand a word of!”

“What does he mean by ‘dope,’ anyway?” mused Corinne. “I can’t imagine,
unless it’s ‘news’ or ‘information.’ You just have to _construe_ his
remarks, as you do the Latin! I think we’ll have to get a dictionary of
slang if he keeps on like this!”

“But, oh, what _do_ you suppose he is finding out!” exclaimed
Margaret. “What can he possibly know that can have anything to do with
our secret?”

“You never can tell!” said Bess. “He goes snooping around this
neighborhood in all sorts of places, and talks with all sorts of
people. Perhaps he _has_ stumbled on something, though I have my
doubts. But here he comes now!”

Alexander entered the house, slamming the basement door and singing at
the top of his high sweet voice:

“On Richmond Hill there lived a lass,
More bright than May-day morn!”

After a preliminary scuffle and dispute with Sarah in the kitchen,
probably over the question of cake, he came galloping upstairs, and
burst in upon them with a military salute and:

“Hullo, pals! Do I have to give the high sign and the grand salaam?”

“Never mind that!” laughed Corinne. “Hurry up and tell us about this
wonderful thing you know. We’re crazy to hear!”

Alexander was visibly flattered, and drew a chair to the group by the
fire, with an air of great importance.

“Well, it’s this way,” he began. “It hit me all of a sudden the other
day, that I had the dope on something that might be right in your line
o’ goods. But I wasn’t sure, and I wanted to nail it. Now I _have_
nailed it—and it’s O.K.!”

“Tell us, quick! Quick!” cried Margaret.

“Hey! put on the brakes a minute, kid!” he commented. “If you go so fast,
you’ll bust your speedometer! Do you know where McCorkle’s stable is?”

All but Corinne nodded. For her enlightenment, he explained: “It’s
around on Varick Street between Charlton and Van Dam, on this side of
the way.”

“It’s a funny old place, isn’t it!” interrupted Margaret. “Sarah
sometimes wheels me past it. The building looks awfully ramshackly. But
what about it? Surely it can’t have anything to do with _our_ affair!”

“Just you douse your sparker and save gasoline!” chuckled Alexander.
“Shows how much _you_ know about things! You _needed_ a man on this
job! As I was going to say, I know Tim Garrity pretty well—he has
charge of the horses. We’re pretty good pals, and he gives me a whole
lot of interesting dope, off and on. Last summer he told me something
that stuck in my crop, but I didn’t think of it again till the other
day. Then I thought I’d go and nail it for certain, before I told you
kids, and I got him to reel it off again yesterday. It’s the dope, all
right! I saw it myself!”

“For gracious sake, Alexander, don’t keep us in suspense another
minute!” implored Corinne. “Tell us quick!”

“All right! Now I’m going to shoot! You remember telling me about the
theater that old house was turned into? Well, Tim once told me that the
stable was built right over where an old theater had stood,—on the
very foundations,—and in the back, where the stalls are, you could see
a part of the old stage, the paintings on the beams, and frescoes—he
called ’em! He was quite proud of it!”

The listening four were now sitting up straight and tense. He went on:

“I didn’t pay much ‘tention to it at the time. Didn’t interest me!
Rather be talking about baseball! But the other day, after all you told
me, I fell for it again. Yesterday I went round and made him tell me
all over again and show it to me, too. I guess we’ve hit the trail,
kids! It was there, all right! Funny old gilt do-dabs, and you could
just make out the shape of the stage, curved, the way they have ’em in
the theaters now.”

He stopped, and every one drew a long breath.

“Alexander, you are certainly a trump!” sighed Corinne. “This is the
best discovery yet. But I’m surprised that the site of the house should
be on Varick Street. Most books said it faced on Charlton.”

And Bess added her say:

“This is certainly awfully interesting, but I’m blest if I can see how
it’s going to be of the slightest _help_!”

“Say, you’re what us baseball fans call a bonehead,” and Alexander
chuckled derisively. “I’ll bet Corinne’s fallen for it already, without
being told!”

“I confess, I don’t see _just_ how it helps,” admitted Corinne,
“unless—unless—there’s some part of the old, original house left.”

“That’s the line o’ talk!” shouted the boy, triumphantly. “I knew you’d
hit the bull’s-eye if any one did! There sure _is_ something of the old
house left, and that is—the _beams_ that supported the cellar ceiling!
They make the foundation of the stage!”

This time Alexander certainly scored a sensation.

“The beams—_the beams_!” cried Margaret.

“Then there must be the one that had the secret hiding-place in it!”

“Now you’re talking!” remarked Alexander.

“But did you _see_ it? Can you get _at_ it?” demanded Corinne.

“There’s where Central cuts you off! I examined the thing carefully,
and got Tim to tell me all he knew. But we found that the stable only
went part of the way through the old cellar of the house; the two ends
are cut off and underground—or at least they’re behind the side walls
of the stable. Can you beat it?”

“Then we can’t get at it after all!” wailed Margaret, disappointed all
the more keenly for the high hope that had been raised.

“Nope! We just can’t get at it—as things stand now!”

“Isn’t there _any_ way you can think of, Alexander?” demanded Corinne.
“Think what we might find in that secret nook—gold, jewels, papers of
great value,—oh! this is exasperating! Can’t you think of _some_ way?”

Alexander, however, only appeared to lapse into deep reverie.

“I haven’t showed you my whole line o’ goods yet!” he confessed, after
submitting them to an interval of soul-satisfying suspense.

“You haven’t—what?” echoed Corinne uncertainly.

“Told you—all—I know!” he translated obligingly.

“Well, for goodness’ sake, go on! How you do tease!”

“Here it is: in a few weeks they’re goin’ to begin to widen Varick
Street and put a subway through.”

They only gazed at him, after this statement, in uncomprehending

“You don’t get me yet?” he went on. “Well, that means they’re going to
do a good deal of altering.”

Still they appeared unenlightened.

“Gee! but you four are _thick_!” he cried at last. “The only way they
can widen it is by tearing down all the houses on one side. And that’s
just what they’re going to do on _this_ side! McCorkle’s stable has got
to go. Now are you on?”

“Then—then—” stuttered Corinne.

“_Then_ we can get at the secret beam!” announced Alexander in triumph.