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:

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 bewilderment.

"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.