Monsieur Jean Saint Rocheville lived by his wits, and, being rather witty, he lived rather well. In the beginning he hadn’t been Monsieur Jean St. Rocheville at all. Born Jones, christened James Aloysius, nicknamed Jimmie, he had been, first, a pickpocket. Sheer ability lifted him above that; and it came to pass that he graduated from all the cruder professions — second-story work, burglary, and what not — until now, when we meet him, he was a social brigand famous under many names.

For instance, in two cities of the West he was being industriously sought as Wilhelm Van Der Wyde, and was described as of the aesthetic, musical type — young, thick-spectacled, clean-shaven, long-haired, and pale blond, speaking English badly and profusely.

In New York, the police knew him as Hubert Montgomery Wade, card sharp and utterer of worthless checks; and described him as taciturn, past middle age, with fluffy, iron-gray hair, full iron-gray beard, and a singularly pallid face. As we see him, he seemed about thirty, slim, elegant, aristocratic of feature, with close-cut brown hair, carefully waxed mustache, and a suggestion of an imperial. Also, he spoke English with a slight accent.

Monsieur St. Rocheville was smiling as he strode through the spacious estate of Idlewild, whipping his light cane in the early-morning air of a balmy June day. On the whole, he had little to complain of in the way the world was wagging. True, he had failed, at his first attempt, to possess himself of the superb diamond necklace of his hostess, Mrs. Wardlaw Browne; but it had not been a discreditable failure; there had been no unpleasant features connected therewith, no exposure; not even a shadow of suspicion. Perhaps, after all, he had been hasty. His invitation had several weeks to run; and meanwhile here were all the luxuries of a splendid country place at his command — motors, horses, tennis, golf, to say nothing of a house full of charming women and several execrable players of auction, who insisted on gambling for high stakes. And auction, Monsieur St. Rocheville might have said, was his middle name.

Idly meditating upon all these pleasant things, St. Rocheville dropped down upon a seat in the shade of a hedge overlooking the rose garden, lighted a cigarette, and fell to watching the curious evolutions of three great velvet-black birds swimming in the air above him. Now they rose in a vast spiral, up, up until they were mere specks against the blue void, only to drop sheerly almost to the earth before their wings stayed them; now with motionless pinions, floating away in immense circles; again darting hither and yon swiftly as an arrow flies, weaving strange patterns in the air. Something here for the Wright brothers to learn, Monsieur St. Rocheville thought lazily.

Came finally an odd whistle from the direction of the house behind him. The three birds swooped down with a rush and vanished beyond the hedge. Curiously St. Rocheville peered through the thick-growing screen. On a second-story balcony stood a girl with one of the birds perched upon each shoulder, and the third at rest on her hand.

“Well, by George!” exclaimed St. Rocheville.

As he looked, the girl flipped something into the air. The birds dived for it simultaneously, immediately returning to their perches. Fascinated, he looked on as the trick was repeated. So this was she, to whom he had heard some one refer as the Jackdaw Girl — the young lady he had caught staring at him so oddly the night before, just after her arrival. He had been introduced to her between rubbers — a charming, piquant wisp of a creature, with big, innocent eyes and cameo features, much given to gay little bursts of laughter. Her name? Oh, yes. Fayerwether — Drusila Fayerwether.

St. Rocheville ventured into the open. Miss Fayerwether smiled, and flung a titbit of some sort directly at his feet. The birds came for it like huge black projectiles. Involuntarily he took a step backward. She laughed.

“They won’t hurt you, really,” she assured him mockingly. “They are quite tame. Let me show you.” She held aloft a slice of toast; the powerful black wings quivered expectantly. “No,” she commanded. The toast fell at St. Rocheville’s feet. Neither of the birds stirred. “Hold it in your left hand,” she directed. Mechanically the astonished young man obeyed. “Extend your right and keep it steady.” He did so. “Now, Blitz!”

It was a command. The bird from her left shoulder, the largest of the three, came hurtling toward St. Rocheville with a shrill scream. For an instant the giant wings beat about his ears, then the talons closed on his right hand in no gentle grip, and man and bird stared at each other. To the young man there was something evil and cruel in the beady, fixed eyes; in the poise of the head on the glistening, snakelike neck; in the merciless claws. And, gad, what a beak! It was a thing to tear with, to mutilate, destroy.

St. Rocheville shuddered. The whole performance was creepy and uncanny. It chilled his blood. It seemed out of all proportion, this exquisite, dainty, pink-and-white girl, and the sinister, somber, winged things —

He drew a breath of relief when Blitz, having solemnly gobbled up his toast, flew away to his mistress.

“They are my pets,” she said affectionately. “Aren’t they beautiful? Blitz and Jack and Jill I call them.”

“Strange pets they are, mademoiselle,” remarked St. Rocheville gravely. “How did you come to choose them?”

“Why, I’ve known them always,” she replied. “Blitz here is old enough, and I dare say wise enough, to be my grandfather. He is nearly sixty, and was in my family thirtyfive years before I was born. He used to stalk solemnly around my cradle like a soldier on guard, and swear dreadfully. He talks a little when he will — half a dozen words or so. Jack and Jill are younger. From their conduct, I should say they haven’t yet reached the age of discretion.”

“Would you mind telling me,” he questioned curiously, “how a person would proceed to tame a — a flock of flying machines like that?”

“Sugar,” replied Miss Fayerwether tersely. “They will do anything for sugar.”

“Sugar!” Blitz screamed harshly, ruffling his silky plumage. “Sugar!”

Monsieur St. Rocheville went away to keep a tennis engagement. Miss Fayerwether disappeared into her room, leaving the three birds perched on the rail of the balcony. On the court, Rex Miller was waiting for St. Rocheville with a question:

“Meet the new girl last night? Miss Fayerwether?”

“Yes.”

“They say she’s a bird charmer,” Rex went on. “She charmed me, all right. Gad, I always knew I was a bird!”

In his own apartments again, St. Rocheville, hot from his exertions on the tennis court, was preparing for a cold plunge, when Blitz fluttered in at the window and perched himself familiarly on the back of a chair.

“Hello!” said St. Rocheville.

“Hello!” Blitz replied promptly.

Astonished, the young man burst out laughing — a laugh which died under the steady glare of the beady eyes. Again, for some unaccountable reason, he was possessed of that singular feeling off horror he had felt at first. He shook it off impatiently and entered the bathroom, leaving Blitz in possession.

He returned just in time to see the big bird darting through the window with something bright dangling from the powerful beak. He knew instantly what it was — his watch! He had left it on a table, and the bird had taken advantage of his absence to steal it. He started toward the window on a run; but, struck by a sudden thought, he stopped, and stood staring into the open, the while he permitted an idea to seep in. Finally he dropped into a chair, his agile mind teeming with possibilities.

Suppose — just suppose — Blitz had been taught to steal? Absurd, of course! Blitz was probably an upright, moral enough bird according to his own lights; but couldn’t he be taught to steal? Either Blitz or another bird like him? He had heard somewhere that magpies would filch any glittering thing and secrete it. Why not jackdaws? Weren’t they the same thing, after all? He didn’t know.

A tame bird, properly trained, cunning, wary, with an innate faculty of making acquaintances, and powerful on the wing!

St. Rocheville forgot all about his watch in contemplation of a new idea. By George, it was worth an experiment, anyway!

There was a light tapping at his door.

“Monsieur St. Rocheville!” some one called.

“Yes?” he answered.

“It is I, Miss Fayerwether. I think I have your watch here. One of my birds came in my window with it from this direction. Your window was open, so I imagine he — he stole it.”

St. Rocheville pulled his bath robe about him and peered out. Miss Fayerwether, with disturbed face, held the watch toward him — the great, solemn-looking bird was perched upon one shoulder.

“Hello!” Blitz greeted him socially.

“It is my watch, yes,” said St. Rocheville. “Blitz paid me a visit and took it away with him.”

“Naughty, naughty!” and Miss Fayerwether shook one rosy finger under the bird’s nose. “He embarrasses me awfully sometimes,” she confided. “I can’t keep him confined all the time; and he has a trick of picking up any bright thing and bringing it to me.”

“Please don’t let it disturb you,” St. Rocheville begged. “As for you, Monsieur Blitz, I’ll keep my eye on you.”

Miss Fayerwether vanished down the hall, scolding.

So Blitz had a trick of picking up bright things, eh? Monsieur St. Rocheville was pleased to know it. It was only a question, then, of training the bird to bring the thing he picked up to the right place. Assuredly here was an experiment worth while. In failure or success he was safe. No sane person could blame him for the immoral acts of a bird.

St. Rocheville seemed to have conquered his aversion to Blitz and Jack and Jill, for during the next week he spent hours with them; and hours, too, with their charming mistress. Sometimes he would play games with the birds — curious games — always in the absence of Miss Fayerwether. He would toss bright bits of glass, or even a finger ring, into the grass, or into the open window of his room, and the birds would go hurtling off to search. At length they came to know that there would be a lump of sugar for each on their return, with two pieces for the bird who brought the ring. St. Rocheville found it an absorbing game. He played it for hour after hour, for day after day.

All these things immediately preceded the first public knowledge of that series of robberies within a district of which Idlewild was the center. Miss Fayerwether, it seemed, was the first victim. She had either lost, or mislaid, she said, a diamond and ruby bracelet, and asked Mrs. Wardlaw Browne to have her servants look for it. She pooh-poohed the idea of theft. She had been careless, that was all. Yes, the bracelet was quite valuable; but it would doubtless come to light. She wouldn’t have mentioned it at all except for the fact that it was an heirloom.

This politely phrased request opened the floodgates of revelation. Rex Miller had lost a rare scarab stickpin; the elderly Mrs. Scott was minus three valuable rings and an aquamarine hair ornament; Claudia Chanoler had been robbed of a rope of pearls worth thousands — robbed was the word she used; an emerald cameo, the property of Agatha Blalock, was missing. Following closely upon these mysterious happenings came word to Mrs. Wardlaw Browne of similar happening at the near-by estates of friends. A dozen valuable trinkets had vanished from the Willows where the Melville Pages had a house party; and at Sagamore, Mrs. Willets was bewailing the loss of an emerald bracelet which represented a small fortune.

The explosion came the night Mrs. Wardlaw Browne’s diamond necklace was stolen. There had been an unpleasant scene of some sort in the card room. Rex Miller seemed to think that there was more than luck in the cards Monsieur St. Rocheville held; and he intimated as much. All things considered, Monsieur St. Rocheville behaved superbly. Being the only winner at the table, he tore the score into bits, and it fluttered to the floor. The other gentlemen understood that he disdained to accept money so long as a doubt remained. So the game ended abruptly, and they joined the ladies in the drawing-room. Ten minutes later Mrs. Wardlaw Browne’s necklace vanished utterly.

So ultimately it came to pass that The Thinking Machine — more properly, Professor Augustus S. F. X. Van Dusen, Ph. D., F. R. S., M. D., LL. D., et cetera, et cetera, logician, analyst, and master mind in the sciences — turned his crabbed genius upon the problem. He consented to do so at the request of Hutchinson Hatch, newspaper reporter; and, singularly enough, it was Monsieur Jean St. Rocheville in person who brought the matter to the reporter’s attention. Together they went to The Thinking Machine.

“You know,” St. Rocheville took the trouble to explain, “every time I read of a robbery of this sort, either in a newspaper or in fiction, some foreign nobleman is always the villain in the piece.” He shrugged his shoulders. “It is an honor I do not desire.”

“You are a nobleman, then?” queried The Thinking Machine. The narrowed, pale-blue, squinting eyes were fixed tensely upon the young man’s face.

“No.” St. Rocheville smiled.

“Extraordinary,” murmured the little scientist. “And who are you?”

“My father and my father’s father are bankers in France.” St. Rocheville lied gracefully. “The situation at Idlewild is —”

“Where?” The Thinking Machine interrupted curtly.

“Idlewild.”

“I mean, where is your father a banker?”

“Paris.”

“In what capacity? What’s his position?”

“Managing director.”

“What bank?”

“Credit Lyonnaise.”

The Thinking Machine nodded his satisfaction and dropped his enormous head, with its thick, straw-colored thatch, back against the chair comfortably, his slim fingers coming to rest precisely tip to tip. Monsieur St. Rocheville stared at him curiously. Obviously here was a person who was not to be trifled with. However, he felt he had passed his preliminary examination, unexpected as it was, with great credit. Not once had he forgotten his dialect; not for a fraction of a second had he hesitated in answering the abrupt questions. Ability to lie readily is a great convenience.

“Now,” The Thinking Machine commanded, his squinting eyes turned upward, “what happened at Idlewild?”

Inadvertently or otherwise, St. Rocheville failed to refer, even remotely, to the three great velvet-black birds — Blitz and Jack and Jill — in his narrative of events at Idlewild. It was rather a chronological statement of the thefts as they had been reported, with no suggestion as to the manner in which they might have been committed.

“Now,” and St. Rocheville spoke slowly, as one who wanted to be certain of his words, “I come down to those things which happened immediately before the disappearance of Mrs. Wardlaw Browne’s necklace. Frankly my own statement will place me in rather a compromising position — that is, my real motive may not be understood — but it is better that I should tell you in the beginning things that you will surely find out.”

“Decidedly better,” The Thinking Machine agreed dryly. He didn’t alter his position.

“Well, you must know that at Idlewild the men play auction a great deal, and —”

“Auction?” The Thinking Machine repeated. “What is auction, Mr. Hatch?”

“Auction bridge,” the reporter told him. “A game of cards — a variation of whist.”

Monsieur St., Rocheville stared from the wizened little scientist to the reporter incredulously. He would not have believed a person could have lived in a civilized country and not know what auction was. Perhaps he wouldn’t have believed, either, that The Thinking Machine never read a newspaper. So circumscribed is our own viewpoint.

“At Idlewild the men play auction a great deal,” The Thinking Machine prompted. “Go on.”

“Auction, yes,” St. Rocheville resumed. “It happens sometimes that the stakes are rather high. On the night Mrs. Wardlaw Browne’s necklace was stolen, four of us were playing in the card room — a Mr. Gordon and myself as partners against a Mr. Miller and Franklin Chanoler, the financier.” He hesitated slightly. “Mr. Miller had been losing, and in a burst of temper he intimated that — that I— that I— er —”

“Had been cheating,” The Thinking Machine supplied crabbedly. “Go on.”

“As a result of that little unpleasantness,” St. Rocheville continued, “the game ended, and we joined the ladies. Now, please understand that it is not my wish to retaliate upon Mr. Miller. I have explained my motive — I don’t want to be made a scapegoat. I do want the actual facts to come out.” Some subtle change passed across his face. “Mr. Miller,” he said measuredly, “stole Mrs. Wardlaw Browne’s necklace!”

“Miller,” Hatch repeated. “Do you mean Rex Miller?”

“That’s his name, yes — Rex Miller.”

“Rex Miller? The son of John W. Miller, the millionaire?” Hatch came to his feet excitedly.

“Rex Miller is his name, yes,” St. Rocheville shrugged his shoulders.

“Oh, that’s impossible!” Hatch declared.

“Nothing is impossible, Mr. Hatch,” interrupted The Thinking Machine tartly. “Sit down. You annoy me.” He shifted his pale-blue eyes, and squinted at Monsieur St. Rocheville through his thick spectacles. “How do you know Mr. Miller stole the necklace?”

“I saw him slip it into the pocket of his dress coat,” St. Rocheville declared flatly. “Naturally, I had an idea that, when he drew Mrs. Wardlaw Browne aside immediately after we came out of the card room, it was his intention to — to denounce me as a card sharp. You may imagine that I was watching them both closely, because my honor was at stake. I wanted to see how she took it. It seems that he said nothing whatever to her about the card game; but he did steal the necklace. I saw him hiding it.”

Fell a long silence. With inscrutable face The Thinking Machine sat staring at the ceiling. Twice St. Rocheville shifted his position uneasily. He was wondering if his story had been convincing. Adroit mixture of truth and falsehood that it was, he failed to see a single defect in it. Hatch, too, was staring curiously at the scientist.

“I understand perfectly your hesitation in going into details,” said The Thinking Machine at last. “Under all the circumstances your motive might be misconstrued; but I think you have made me understand.” He rose suddenly. “That’s all,” he said. “I’ll look into the matter tomorrow.”

Monsieur St. Rocheville was about to take his departure, when The Thinking Machine stopped him for a last question.

“You used a phrase just now,” he said. “I am anxious to get it exactly — something about your father and your father’s father —”

“Oh! I said”— Monsieur St. Rocheville obliged —“that my father and my father’s father were bankers in Paris.”

“That’s it,” said the little scientist. “Thanks. Good day.”

Monsieur St. Rocheville went out. The Thinking Machine scribbled something on a sheet of paper and handed it to the reporter.

“Attend to that when you get to your office,” he directed. Hatch read it, and his eyes opened wide. “Also, do you happen to know a native Frenchman who speaks perfect English?”

“I do; yes.”

“Look him up, and ask him to repeat the phrase, ‘My father and my father’s father.’”

“Why?” inquired the reporter blankly.

“When he says it you’ll know why. Immediately this other matter is attended to come back here.”

Monsieur St. Rocheville’s troubled meditations were disturbed by the appearance of Miss Fayerwether around a bend in the walk. Fluttering ............