[{1}]

Issued Weekly. Entered as Second-class Matter at the New York Post Office, by Street & Smith, 79-89 Seventh Ave., New York. Copyright, 1915, by Street & Smith. O. G. Smith and G. C. Smith, Proprietors.

TERMS TO NICK CARTER STORIES MAIL SUBSCRIBERS.

(Postage Free.)

Single Copies or Back Numbers, 5c. Each.

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No. 148. NEW YORK, July 10, 1915. Price Five Cents.

THE MARK OF CAIN;
Or, NICK CARTER’S AIR-LINE CASE.

[{2}]

Edited by CHICKERING CARTER.

CHAPTER I.
WHAT THE GIRL DID.

The girl at the switchboard held her breath. The detective waiting in the business office saw her. The girl at the switchboard was Helen Bailey. The waiting detective was Nick Carter.

No man was ever more quick than he to rightly interpret a facial expression. The partition through which he saw her was of glass, or a portion of it, dividing the general manager’s office in the central telephone exchange from the room in which the great switchboards were stationed.

There were other girls, half a score of them, seated in front of the innumerably perforated boards. They were too busy to notice one another. Their eyes were intent upon their work. Their deft hands flew from plug to plug, withdrawing some, inserting others. Their frequent, monotonous calls, the noise of the buzzers and the snapping of the rubber-covered plugs were the only sounds to be heard in that busy room.

“Hello! hello!”

“Number, please.”

“The line is busy.”

They were like machines, those switchboard girls, human, living, palpitating machines, each a connecting link for others in every phase of life, every calling and vocation, from the gilded mansions of exclusive society to the smoke-begrimed dives of the underworld. They are the servants of all, and, in a measure, the confidantes of all.

The girl who had caught Nick Carter’s eye was striking not alone because of her facial expression at that moment, but because of her remarkable grace and beauty. She was about nineteen, a pronounced blonde, with regular features, large, blue eyes, and a sensitive mouth, a pink-and-white complexion, an abundance of wavy, golden hair, crowning a [{3}]shapely head, finely poised on a graceful, slender, yet well-developed figure, then clad in a navy-blue skirt and a dainty white waist.

It was the expression on her fair face, however, that had riveted the detective’s attention, though he could see her only in part profile.

Nick never had seen a look of more poignant anguish on a human face.

The girl was pitched forward on her high chair, her hand grasping one of the plugs which she had pushed into the switchboard—and now seemed impelled to withdraw.

That would have abruptly ended the conversation between the two persons whom she had brought into communication, and to whose intercourse she was listening.

That she really was listening, listening as one might to the reading of one’s own death warrant, was painfully apparent. Her eyes seemed to be starting from her head, but with the wildly vacant expression of one horrified, one whose mind was elsewhere. Every vestige of color had left her cheeks. Her lips were gray and drawn, her graceful figure as motionless as if every nerve and muscle was as strained and tense as a bowstring.

“Great Scott!” thought Nick, watching her. “To whom is she listening, and to what?”

The girl suddenly withdrew the plug.

Then, with a quick change of expression, with a look of heart-racking determination, she inserted it again, renewing the telephone connection.

Then she listened again, ghastly and horrified, for nearly a minute—and then her head dropped to one shoulder as if her neck was hinged, her arm fell like that of a corpse, dragging the plug out of the switchboard, while her tense form relaxed and fell from the chair, dropping with a thud upon the floor beside it.

Nick Carter had seen what was coming, and he already was on his way to the room, darting out of the manager’s office and through the adjoining corridor. He heard the screams of the frightened girls, when he en[{4}]tered, and, with quick discrimination, he turned to the least-alarmed one and said:

“She has only fainted. Bring a glass of water. Be quick about it.”

“Yes, sir.”

The girl addressed ran to a near closet and obeyed him.

Nick raised the prostrate girl a little, supporting her against his knee, and, with a wet handkerchief, he bathed her brow and cheeks, paying no attention to the fright and consternation of his observers.

The girl revived in a very few moments. A low moan, as pathetic as the facial expression which had preceded her collapse, broke from her gray lips. Her eyelids fluttered spasmodically, then were raised, and she gazed up vacantly at the detective’s kindly face.

“Did they—did they get him?” she gasped impulsively, almost frantically. “Did they—did they get him?”

Nick waved aside the several girls who had gathered near.

“Open one of the windows!” he commanded. “Give her some fresh air. Get whom, my girl?”

The last was addressed to the stricken girl, while Nick gently raised her to a sitting position on the floor.

She turned and looked at him, then suddenly seemed to realize what had occurred. She gazed at Nick again, striving to rise, and replied, more calmly:

“Get whom? What do you mean?”

“Don’t you know what I mean?” Nick inquired, helping her to a chair.

“No, I don’t,” she replied. “Thank you for assisting me. I’m sure I don’t know what you mean.”

Nick was sure of the contrary, but he did not say so. Instead, he smiled and explained his presence there by saying:

“I happened to be in the manager’s office when you fainted. I saw you fall and hurried in to aid you. Are you subject to such attacks?”

“No, sir. I don’t remember ever having fainted away before.”

“You may have heard something that alarmed you, or——”

“No, no, sir; nothing of the kind,” interrupted the girl. “I cannot account for it.”

“Do you remember what number had been called, what connection you had made?”

“No, sir.”

“Or what was being said?”

“I do not,” the girl insisted. “I remember nothing about it. I know only that I was not feeling well this morning. I awoke with a racking headache. I suddenly felt dizzy and then I fainted. That is all I know about it. Please don’t question me further. I’m able, now, to return to my work. Thank you again, sir.”

Nick knew that the girl was lying, but he alone had observed her agitation for several moments before she fainted. She still was pale and nervous, trembling visibly while she replied to his questions, but it was obvious that she was determined to admit nothing in regard to what she evidently had heard at the switchboard.

Nick decided not to press her further, therefore, and he bowed indifferently and returned to the business office.

Manager Lawton, for whom he had been waiting, came in a few moments later and Nick transacted the business[{5}] for which he had called. He then quietly told him of the incident and pointed out the girl who had fainted.

“What is her name?” he then inquired.

“Helen Bailey,” replied Lawton, smiling. “She is the most capable girl in our employ.”

“She is a very beautiful girl, too,” Nick observed.

“And as good as she is beautiful,” Lawton said, with a nod. “The man who gets her for a wife, Nick, will get a treasure.”

“Where does she live?”

“She boards in Lexington Avenue.”

“With her parents?”

“No. Both are dead. She has only a brother, I believe, who—well, I know very little about him. Why are you so interested in the girl?” Lawton added, laughing. “You’re not smitten with her beauty, Nick, are you?”

Nick smiled and shook his head; then arose to go. As he passed out he glanced again through the glass partition at the several girls at the switchboards.

Helen Bailey had resumed her work as if nothing had occurred.

Nick still had her in mind when he left the building and walked up the street. He had in mind, too, the impulsive, almost frantic words that had broken from her when, with returning consciousness, she took up her train of thoughts just where she had left them—the thoughts which had brought that terrible expression to her fair, lovely face.

“‘Did they get him?’” he said to himself. “By Jove, that was a rather significant question, asked as she asked it and under such circumstances. Get whom? Get him for what? Was some man in danger, one with whom she is in love, perhaps, and for whose sake she was so shocked and alarmed? There certainly was some serious reason for that horrified expression and her sudden collapse. I would have been glad to aid her if she would have confided in me, but she preferred to lie, and—well, it was up to her. It is barely possible that she will regret it later.”

CHAPTER II.
A FRIEND IN NEED.

Nick Carter’s intuition in regard to the telephone girl was verified much sooner than he really expected. He entered his Madison Avenue residence about an hour later and found in the library his two chief assistants, Chickering Carter and Patsy Garvan. He heard the following remarks from Patsy as he was approaching the open door.

“She certainly is a peach, Chick, and I felt dead sorry for her. She’s in wrong, all right, but I don’t half credit the charges, at that.”

“What charges, Patsy?” Nick inquired, entering. “Of whom were you speaking?”

“Of a girl I saw at police headquarters about twenty minutes ago,” said Patsy, turning from his desk. “I went down there on that Waldron case.”

“Was the girl under arrest?”

“Yes.”

“For what?”

“For helping a crook elude the police,” Patsy explained. “She denied it, chief, sobbing as if her heart would break; but they’re putting her through the third degree now, hoping to break her down and force a confession from her. My money goes on the girl, chief, all the same.[{6}]”

“Who is the girl?” Nick questioned. “Did you learn any of the circumstances?”

“Sure!” nodded Patsy. “Her name is Helen Bailey.”

“H’m, is that so?”

“She’s a telephone girl, and a sister of Barton Bailey, wanted for robbery in Mantell & Goulard’s big department store, where he was employed at the time. He got away with a diamond sunburst, you remember, and nearly cracked the skull of Gus Flint, one of the store detectives, who had seen him lift the bauble and tried to prevent his escape. That was six months ago.”

“Yes, I recall the case,” said Nick, with a more serious expression. “But what are the circumstances bearing on the girl’s arrest?”

“It seems that Bart Bailey was seen going into a house in East Forty-third Street about ten o’clock this morning,” Patsy continued. “He was in disguise, but was recognized by some one who declined to give his name to the headquarters chief, to whom he hastened to telephone.”

“He stated, I suppose, that he had seen Bailey going into the house.”

“That’s what,” said Patsy. “The chief then called up the precinct station and told the sergeant to go to the house with a couple of men and get Bailey.”

“I see.”

“Before he could finish giving his instructions, including the number of the house, the telephone connection was suddenly broken. Nearly ten minutes passed before the chief could get it renewed, and that brief delay cost the guns their man. When they arrived at the house, Bailey had been gone about three minutes.”

“Did the chief know his sister is employed in the telephone exchange?”

“Bet you!” exclaimed Patsy sententiously. “Let him alone to have learned that. He has had men out after Bailey for nearly six months. He learned, too, that Helen Bailey was the operator who connected him with the precinct station, and he noticed while talking with the sergeant that the connection was broken once and quickly renewed.”

“Precisely,” thought Nick, recalling his own observations. “He was not alone.”

“Half a minute later,” Patsy added, “it was broken completely, and the chief lost his man. It made him sore, for fair. He knows the girl must have overheard his orders to the sergeant, and he suspects that she purposely cut him off and afterward telephoned her brother to bolt.”

“Not an unreasonable inference,” Nick allowed, a bit grimly. “Nevertheless, Patsy, the girl did nothing of the kind.”

“Gee whiz!” Patsy returned, gazing. “Are you wise to something bearing on the case? Do you mean——”

“Never mind what I mean,” Nick interposed, glancing at his watch. “I’ll inform you later. I’ll knock those suspicions out of the chief’s head in about two shakes of a lamb’s tail. Helen Bailey is a heroine—much more heroic than most girls would have been under the same temptation.”

Nick did not wait to explain to Chick and Patsy. Disregarding their looks of surprise, he replaced his hat and started immediately for the police headquarters. He was so well known there, where his services were very frequently required, that no one would have thought of[{7}] opposing him. He learned that the chief still was talking with Helen Bailey in his private office, into which Nick walked without the ceremony of knocking.

The chief regarded him with a look of surprise. It became more marked, even, when Helen Bailey, pale and with eyes red from weeping, uttered a low cry and exclaimed:

“Oh, sir, here is the man who assisted me. This is the man I have told you about. He knows that my faint was not feigned. He will tell you——”

“I will tell the chief all that is necessary, Miss Bailey,” Nick interposed, smiling and shaking hands with her. “I am very glad to be able to befriend you.”

“Goodness!” said the chief, with his austerity suddenly vanished. “What do you know about this matter, Nick?”

“I know all about it, chief,” Nick replied, taking a chair. “Garvan was here when this young lady was brought in. He has told me why she was arrested and what you suspect. But you’re in wrong, chief, and I’ve come here to say a word for the girl.”

“A word from you, Carter, is usually enough,” replied the chief, while Helen Bailey, hearing the name of the famous detective, gazed at him with amazement and inexpressible relief.

“I can explain in a nutshell,” said Nick. “I was in the telephone office, chief, and saw all that occurred.”

“What did you make of it, Carter?” asked the chief.

Nick then told him all he had seen and what he had done.

“This girl did not cut you off, chief, but quite the contrary,” he added. “She knew, nevertheless, precisely what your communication signified. I saw her withdraw the plug once, then willfully reinsert it. I saw how terribly she felt, how terribly she was tempted—and I now know, too, with what heroism she resisted the temptation and stuck to her duty, though it involved the sacrifice of her own brother.”

The chief gazed for a moment at the detective, who had spoken quite feelingly.

“The girl has told me that, Nick, but I could not credit it,” he said, more gravely.

“It is true, chief. You can bank on it.”

“I’m mighty glad you have showed up, then.”

“I knew you would be.”

The chief turned to Helen Bailey and laid his hand on hers.

“Pardon me, my girl,” he said gently. “We have hard duties to perform at times, and duty leaves us no alternative. You are a good girl and a brave girl, and I’m sorry to have given you so much pain and trouble. I now believe all you have told me, and I’m very proud of you.”

Helen was sobbing again, but with mingled gratitude and relief. She turned and grasped Nick’s hand, saying brokenly:

“Oh, Mr. Carter, how can I thank you—how can I thank you?”

“By not trying to do so,” Nick replied kindly. “These little services are the bright spots in our lives. Go and wait for me in the outer office. I wish to talk with the chief a few moments and I then will join you.”

Helen dried her tear-filled eyes and obeyed him.

Nick had remained only to question the chief concerning Bart Bailey, and to find out what had been learned about him in the house he had been seen to enter.

“Nothing was known about him there, Nick,” the chief[{8}] replied. “It is a lodging house and is run by an honest, elderly woman. Bailey was there about ten days ago, remaining only two nights, and requesting the privilege of leaving a suit case until he could call for it.”

“That is why he went there this morning?”

“Yes. He remained only ten minutes.”

“He is a stranger to the landlady, I infer.”

“Yes, a total stranger. She knows nothing about him. I happen to know, however, that he’s a very bad egg, and I wanted to get him.”

Nick remained only a few moments longer, then went to the outer office and rejoined the waiting girl.

“Come with me,” he said pleasantly. “There is no occasion for you to remain here. I don’t think you will ever be wanted again, Miss Bailey.”

“I cannot express my gratitude, Mr. Carter,” she replied, while she accompanied him to the street.

“Don’t try,” smiled Nick. “Tell me something about yourself and your brother. He used to work for Mantell & Goulard, I understand.”

“Yes, sir. Young Mr. Mantell gave him a position there for—for my sake,” said Helen, blushing in a way that Nick rightly interpreted. “But Bart can’t go straight. He is bad, awfully bad. He is only my half brother, sir.”

Nick saw that the topic was a painful one for her, and he decided not to press his inquiries. He learned that the rascal had frequently threatened her, however, because of her refusals to join in his knavish projects, and that the girl stood somewhat in fear of him.

Nick took her Lexington Avenue address, therefore, and promised to aid her again if occasion required it. Smiling in response to her repeated thanks, he then placed her in a taxicab which he hailed and saw her driven rapidly away, well satisfied with the kindly deed he had done, but not supposing for a moment that it would have any further significance.

CHAPTER III.
THE MAN OF LAST RESORT.

“There are detectives, Mr. Carter, and detectives,” said Nick Carter’s visitor. “By that I mean that only half of them are worthy of the name. Half of the remainder are mediocre, and only one in a hundred of the rest is really keen and clever. You, Mr. Carter, are the recognized man of last resort. When all others have failed, it is to you that the harrowed victim of crookdom turns for aid, as the only man in Christendom who can ferret out the truth and round up the guilty. That, sir, is why I am here.”

Nick Carter laughed.

“You are complimentary, Mr. Mantell, and I appreciate your very exalted opinion of me,” he replied, a bit dryly. “All that sounds very nice and pretty, remarkably so, but it does not do what you asserted. It tells me only what impelled you to come here, not why you are here. Suppose you come to the point and tell me why.”

Nick’s visitor joined in the detective’s genial laugh, as did Chick and Patsy, who were seated with them in Nick’s attractively furnished library. It was about seven o’clock in the evening, that of the very day on which had occurred the episodes described.

He was a young man, this visitor, of remarkably frank and prepossessing appearance. He was still under thirty,[{9}] set up like an athlete and scrupulously well dressed. He was the type of man to whom others are instinctively drawn, and to whom women turn for a second look.

Nick long had known him by name and sight, the only son of wealthy Henry Mantell, of Mantell & Goulard, the owners of the vast Sixth Avenue department store to which reference already has been made, and which then was by far the largest establishment of its kind in the country. He was Frank Mantell, of whom Helen Bailey had spoken to Nick in connection with the robbery committed by her recreant brother.

“Come to the point, eh?” he replied, still smiling. “That is a very good suggestion, Mr. Carter, and I will act upon it. Mr. Goulard, the junior partner of our firm, was to have met here to discuss our business with you. Pending his arrival, however, I will do what you suggest and tell you why I am here.”

“Very good. I am all ears,” Nick remarked, knocking the ashes from his cigar.

“I am here, Mr. Carter, because of the tremendous leak in our business,” said Frank, more gravely. “I refer, of course, to the department store of Mantell & Goulard, of which I am one of the managers. My father, you know, is the senior partner.”

“I am acquainted with your father,” Nick bowed. “When was this leak discovered?”

“Six months ago, after our semiannual taking of stock. Our business showed a shrinkage of more than thirty thousand dollars. That of the past six months is even worse, running close to fifty thousand. In other words, Mr. Carter, the leakage the past year is close upon eighty thousand dollars.”

“Much too large to be charged to the profit-and-loss account,” said Nick. “Are you unable to discover the cause?”

“Quite the contrary, Mr. Carter,” said Mantell. “We know the cause.”

“Namely?”

“Robbery.”

“Money?”

“No. Merchandise.”

“You don’t mean that eighty thousand dollars’ worth of merchandise has been taken from your store in the past year, and that you are unable to discover the thieves,” said Nick.

“That is precisely what I mean,” Frank replied, a bit more forcibly. “As a matter of fact, Mr. Carter, we are up against a most extraordinary game of systematic and persistent robbery. Day after day, and frequently during the night, articles of material value disappear most mysteriously from all parts of the store. We don’t know where they go, nor how the thefts are committed. We have not the slightest clew to the identity of the robbers.”

“What kinds of goods are chiefly missing?”

“All kinds, but invariably articles of considerable value. Costly laces of every description, fine handkerchiefs, pocketbooks, and jewelry, full pieces of expensive silks and satins, fine lace draperies, and—but I could not begin to enumerate them. They disappear as if they had evaporated from our shelves, counters, and show cases.”

“Can it be the work of professional shoplifters?”

“Impossible; utterly impossible! It is much too extensive.”

“How about your help?”

“Equally out of the question,” said Mantell decidedly.[{10}] “We employ about nine hundred clerks, but they have absolutely no opportunity for thefts of such character and magnitude. It would be impossible for them to take the goods from the store without being detected. We have had them closely watched, nevertheless, since these daily robberies were first discovered, but we have failed to detect a single thief among our employees.”

“You have store detectives, of course?” said Nick inquiringly.

“Yes, on every floor.”

“Have they accomplished anything?”

“So little, Mr. Carter, that we put the case into the hands of half a dozen headquarters men about two months ago. Their work has been equally futile. Not a piece of the stolen goods has been traced. Not a clew has been found pointing to the identity of the crooks, or the way in which the thefts were committed.”

“That seems very strange,” Nick remarked.

“Strange is right, chief, and then some,” put in Patsy. “There must be a bunch of clever ginks at work along new and original lines.”

“That seems to be about the size of it,” Nick added.

“And that is precisely how the matter stands,” Frank Mantell continued. “As I said in the beginning, Mr. Carter, you are the man of last resort. All others have failed, and we now turn to you for advice and assistance. I think we should have done so at the outset. It would have saved us a barrel of money.”

“You seem to feel sure that I shall succeed in solving the mystery,” smiled Nick.

“Frankly, Mr. Carter, I do,” Mantell rejoined. “Success seems to be one of your invariable acquirements. I feel that it will prove so in this case.”

“Providing I decide to take the case.”

“I hope you will not demur over that.”

“Let me ask you a few questions,” said Nick, drawing up in his chair and dropping his burned cigar into a cuspidor. “Are any headquarters men now at work on the case?”

“No, sir. We dropped the last of them to-day.”

“Your store detectives still are at work?”

“Only in line with their customary duties. They would not in any way interfere with your work.”

“I would not permit them to do so,” Nick said, a bit dryly. “It would be even better, perhaps, if they were ignorant of my interest in the matter. Who besides you knows of your intention to employ me on the case?”

“Only my father, Mr. Goulard, and Mr. Lombard. My father and I look after the correspondence and the financial end of the business. Mr. Goulard and Mr. Lombard have entire charge of operations in the store. Goulard is, of course, the chief director. We decided this afternoon to appeal to you for aid. No one else is informed of our intention.”

“Make it a point, then, to inform no one else,” Nick replied. “I will at least look into the matter and see what I can make of it.”

“Ah. I am glad to hear that.”

“Now, Mr. Mantell, when did you first suspect this system of wholesale robbery and begin to investigate it?” Nick inquired.

“About six months ago,” Frank replied. “We knew of many thefts previous to that time, and tried in vain to discover the culprits. Not until we had taken stock and our books showed such a tremendous leakage, how[{11}]ever, did we realize how extensive a felony we were up against. We then began the investigations that have proved so futile.”

“That was about the time Bart Bailey was seen stealing a diamond sunburst, wasn’t it?”

“Yes, it was,” said Mantell, with a look of surprise. “How did you learn about that?”

“The newspapers mentioned it,” Nick said evasively.

“Ah, yes; I remember.”

“Did you at that time, or since, suspect that Bailey was in league with the gang of crooks committing the numerous robberies? I speak of them as a gang, of course, because such extensive work would require several persons and careful coöperation.”

“We suspected it, certainly, but there was no other evidence in confirmation of it,” Mantell explained. “After the escape and disappearance of Bailey, moreover, the robberies continued as frequently as before. That indicated in a measure that he was not identified with the other thieves.”

“Possibly,” Nick allowed. “I happen to know that Bart Bailey, as he is called, is a somewhat vicious character. Were you aware of that when he was employed in your store?”

Mantell colored slightly, but showed no inclination to hide the truth.

“I was aware of it,” he admitted. “I had a personal reason for giving him employment. Frankly, Mr. Carter, I am deeply in love with his sister Helen Bailey, who is as good and virtuous as he is vicious.”

“You employed him for her sake?”

“Yes. I wanted to give him a chance. I told him just what I knew about him, and gave him a talking to, man-to-man fashion, and he promised to go dead straight and do his best. It was the opportunity of a lifetime, for I would have pushed him forward for all he was worth.” Mantell earnestly added. “But I fear it isn’t in him, Carter, to be anything but a crook.”

“It appears so, Mr. Mantell, surely.”

“I would marry Helen to-morrow, with the sanction of all of my family, if she would have me,” Frank gravely asserted. “But she cannot ignore the fact that her brother is an outlaw of society, and she feels that she must not bring disgrace upon me. Dear, foolish girl! as if she were responsible for the conduct of her brother. Hang it! he’s only her half brother at that, and—ah, that should be Mr. Goulard. We will plan for your campaign against these infernal thieves.”

“There will be no planning with me, Mantell,” Nick replied, as Joseph, his butler, passed through the hall and answered the doorbell. “I do my own planning and work out problems in my own peculiar way. I will be pleased to meet Mr. Goulard, nevertheless, and hear what he has to say.”

Frank Mantell was right in that the caller was Gaston Goulard, and he was presently ushered in by the butler. He was an erect, somewhat imposing man close upon fifty. He was smooth shaved, of dark complexion, with strong features and penetrating black eyes. He had been a widower about four years, having no children, but still retaining his fine Fifth Avenue residence and a retinue of servants. He was a member of the best clubs, and a man of recognized ability, political influence, and social standing.

Mr. Mantell received him graciously and introduced him[{12}] to Chick and Patsy, while Goulard removed his kid gloves and shook hands with all.

“You are here before me, Frank,” he remarked, after greeting the detectives. “I was unavoidably detained.”

“I don’t think it matters,” Mantell replied. “I have told Mr. Carter all that you could have told him and all that he is really inclined to hear. He has consented to take the case and——”

“Very good,” Goulard interrupted, in somewhat brusque and metallic tones. “I am glad to hear it. What do you intend doing, Mr. Carter? That is the main question.”

Nick gazed at him quite intently.

“I really don’t know,” he replied.

“Don’t know?”

“Not yet.”

“You mean——”

“Only what I say—that I don’t know,” Nick put in, smiling. “I must consider the matter. I must determine what best can be done. I must visit your store and size up the opportunities for such wholesale robbery, before I can say what I will do. You can hardly expect more of me at present, Mr. Goulard.”

“Very true, perhaps,” Goulard admitted, with signs of reluctance. “We are up against such a costly game, however, and have found the efforts of other detectives so entirely useless, that I really wondered what steps you would take to discover the thieves.”

“I wonder, too, since hearing Mr. Mantell’s statements,” Nick replied, smiling again. “It appears like a difficult problem, Mr. Goulard.”

“It does, indeed, and you must keep me informed of your progress.”

“I will make it a point to do that.”

“That is all we can reasonably ask, then,” said Goulard, with an approving nod. “If we can aid you in any way, or——”

“I will inform you, Mr. Goulard, in that case.”

“Very good. When will you begin your work?”

“Just as soon as I have decided how to begin it,” said Nick. “Like Davy Crockett, I make sure I am right before going ahead. I think you may expect me, or one of my assistants, at your store to-morrow morning.”

“I would prefer that you give the matter your personal attention,” said Goulard suggestively.

“I always do that, sir, when engaged in an investigation of even the simplest kind of a case,” Nick said, with seeming indifference.

“Gee! if that gazabo gets anything out of the chief, he’ll do it with a double, back-action corkscrew,” thought Patsy, noting Nick’s suave reticence and not half liking the strong, dark face of this second visitor.

Mr. Goulard did not prolong his interview, however, save to discuss the matter in a general way and learn what information Mantell had imparted. It was eight o’clock when the two men left the detective’s residence, Nick seeing them to the door and then returning to the library.

“Well, what do you make of it?” Chick at once inquired. “I saw that you were not inclined to confide your opinions to Goulard. That convinced me that you had formed one, at least.”

“Gee! I was hit in the same spot,” declared Patsy.

Nick smiled and resumed his seat.

“I wouldn’t confide in either of them,” he replied. “I have, as you infer, come to at least one conclusion.[{13}]”

“What is that?”

“These robberies are not the work of shoplifters nor any outside crooks,” said Nick. “They have been much too numerous and varied. The crooks are among the persons employed in the store.”

“I think so, too,” Chick nodded.

“And for that reason alone, Chick, I would confide in no one in the store, from the heads of the firm down to the boy who sweeps the back stairs,” said Nick. “That is a mistake many detectives make, that of blindly confiding, perhaps, in the very culprit they are out to get.”

“Gee! that’s right, chief,” put in Patsy.

“If any inquisitive person in that store learns of my designs, it will be only when they culminate, and his curiosity may cost him something,” Nick pointedly added. “Secrecy is imperative to successful work in a case of this kind.”

“I agree with you,” said Chick, with a nod of approval.

“It sure does look like inside work,” said Patsy. “But how do they get out with the goods? The headquarters men are not lunkheads, nor are the store detectives blind. How do the crooks get out with such quantities of merchandise?”

“We must find the answer to that question,” Nick replied. “Other detectives, in their efforts to discover the crooks themselves, may have neglected to look sharply enough for it. We may meet with more success, in fact, by working backward.”

“Working backward, chief?” questioned Patsy. “What do you mean?”

“By finding out where the goods are disposed of, through what channel they reach their destination, and by working back over the same route, even to the moment of the theft,” Nick explained.

“By Jove, that plan might prove profitable,” said Chick. “The goods cannot have been pawned in this city. The headquarters men would have run them down within forty-eight hours.”

“Undoubtedly,” Nick agreed. “It is safe to assume, nevertheless, that the goods are stolen to be converted into money, which necessitates either pawning or selling them. They may have been shipped to some other city for that purpose.”

“Quite likely.”

“But how are we to learn what city, chief, assuming that you are right?” questioned Patsy.

“I have a hunch that the way will appear,” replied Nick. “There is one other point of which we can take advantage, I think, and it may start us on the case right off the reel.”

“You mean?”

“Bart Bailey’s presence in New York, and what occurred to-day.”

“What do you see in that?”

“I am convinced that Bailey was in league with the other crooks when he stole the diamond sunburst, and it’s a hundred to one that he still is in league with them in some capacity,” Nick explained. “If he had not been stealing the jewel, it probably would have gone the way of the other plunder. The circumstances forced him to bolt with it, however, and to lie low ever since.”

“But how can we take advantage of all that?” asked Chick. “I don’t quite get you.”

“We’ll take advantage of his antipathy for his half[{14}] sister,” said Nick. “He don’t like her, despite their kinship, and he already has repeatedly threatened her.”

“But how take advantage of it?”

“He will hear of what occurred to-day; that she made no intentional move to prevent the police from getting him, despite that she could easily have done so,” said Nick. “Take it from me, Chick, he’ll get after her for that. He will hate her more than before, the knavish rat, and may go even so far as to attempt violence. By keeping an eye on her, therefore, we not only may protect her, but also pick up Bart Bailey himself. Then, if he still is in league with the department-store thieves, we perhaps may trail him to the lair of the entire gang.”

“By Jove, that’s no wild-and-weird fancy,” Chick now declared, with some enthusiasm. “That realty looks good to me, Nick.”

“That being the case. Chick, you had better tackle that string to our bow,” Nick directed. “Pack a grip with what you may need for a few days, and go in disguise to the Lexington Avenue house in which Helen Bailey is boarding.”

“To remain there?”

“Yes, temporarily. Engage a room and board, if possible, and you then will have the girl right under your eye. Reveal nothing to her, however. That might queer an opportunity to pick up her brother.”

“Trust me to have foreseen that,” Chick replied, rising. “I’ll be ready to leave in ten minutes, and will phone you to-morrow morning.”

“Good enough,” Nick said approvingly. “A reference may be required by the landlady. Take the name of Fred Lamont, and say you are a nephew of Mr. Calvin Page, cashier of the Trinity Trust Company. I will presently telephone to Page and inform him of the situation. He will assure the landlady, in case she rings him up.”

“I’ve got you,” Chick nodded, turning to go.

“I will have decided by to-morrow how Patsy and I can best begin operations,” Nick added. “I think we’ll take a look at the store, for a starter, and at a few of its nine hundred clerks.”

“We may pick the crooks from the nine hundred merely by their looks,” laughed Patsy. “That would be going some, chief, for fair.”

CHAPTER IV.
PICKING UP A TRAIL.

Chick Carter appeared at the door of the Lexington Avenue lodging house about nine o’clock that evening, and his ring was answered by the landlady herself, one Mrs. Hardy, to whom he stated his mission and plausibly explained why he applied to her at that hour.

That Chick made a favorable impression upon the woman, moreover, appeared in that he was invited to enter, though Mrs. Hardy added, a bit doubtfully:

“I have only one vacant room at present, sir, and that may not please you. It is a back room on the second floor.”

“I think it will answer,” Chick said agreeably. “I can not say just how long I may remain in New York, but I will pay you liberally for the time I am here. My name is Fred Lamont. I am a nephew of Mr. Calvin Page, cashier of the Trinity Trust Company. You can talk with him by telephone, if you require a reference, and he will assure you that I am a desirable tenant.[{15}]”

“I will do so a little later, Mr. Lamont, if I think it necessary,” said the landlady. “I first will show you the room.”

Chick accompanied her to the second floor and into a small but neatly furnished back chamber.

“That in front is occupied by a young lady, Miss Helen Bailey, who is not at home this evening,” Mrs. Hardy observed, while Chick was glancing around the room. “She has gone to a picture show with a girl who lives a block south from here.”

Chick did not demur over taking the room. It was decidedly satisfactory to him, in fact, to have quarters so near the girl’s room, in that he would be easily able to keep a constant eye on her movements when at home, and to learn whether she was visited by her disreputable brother.

Chick took the room at once, therefore, paying a week in advance, and inquired, while doing so:

“Does Miss Bailey frequently have visitors in the evening? I usually retire quite early. Her room is so near mine that any loud conversation might disturb me.”

“Dear me, no!” exclaimed Mrs. Hardy, with a shrug. “Miss Bailey has only two gentlemen callers, and she always receives them in the parlor.”

“That’s all right, then,” said Chick, smiling agreeably.

“She could pick her choice from most men, Mr. Lamont, as far as that goes,” added the landlady, becoming communicative. “She is a beautiful girl. She could marry the son of one of the wealthiest merchants in New York, if she wanted to, or another one of the firm. I know that, sir, though you may think it improbable.”

“One of the firm,” thought Chick. “By Jove, that must be Goulard. Father and son would not be rivals. Besides, Mantell, senior, now has a wife and family. Goulard is a widower, however, and—h’m, this may be worth looking into.”

Chick decided not to display any undue curiosity at that time. He left his suit case in the room and accompanied Mrs. Hardy downstairs, stating that he had business outside for about an hour, when he would return, and he then left the house.

Three minutes later found him in the vestibuled doorway of a dwelling nearly opposite, from which he could see the electric-lighted avenue for a block in each direction.

Chick reasoned, in view of Nick’s suspicions, that Bart Bailey might already have heard of his sister’s conduct and might possibly be seeking her that very evening, particularly if impending danger necessitated his early departure from the city.

Chick had decided, in fact, that he would see Helen Bailey home after she parted from the girl who had accompanied her to the picture show. He knew that she would be in no danger while having a companion, and the vantage point he had selected enabled him to watch the avenue as far as the location mentioned by the landlady.

“She’ll not return later than eleven o’clock, if she has gone to the movies,” he said to himself. “There is one chance in a hundred, at least, that Bart Bailey already is out to nail her. I’ll take that one chance, having nothing else to do.”

All this was clever work on the part of the Carters, and it bore not unexpected fruit.

Chick had been waiting less than half an hour when[{16}] he saw a slender man in a dark suit coming down the avenue, whose movements immediately warranted suspicion. For he quickly crossed the avenue before arriving at the boarding house, then halted on the opposite side and gazed intently at the second-floor windows.

“By Jove, I’m in right,” thought Chick, after watching him for several moments. “That’s my man, as sure as there’s juice in a lemon. He expected to find the girl at home, but sees that her room is not lighted. He’ll lie low and wait for her, taking a chance that she’ll return alone, unless I’m much mistaken.”

Chick was not mistaken.

Bart Bailey, for the detective had rightly identified him, suddenly recrossed the avenue, and, having glanced sharply around, he slunk into a basement doorway under the rise of stone steps leading up to the front door of the boarding house.

“Does he intend to enter, or will he wait for the girl?” Chick asked himself. “I’ll remain here until she comes, at all events. If he does not then show up, I’ll cross over and enter with her. I’ll give the rat no chance to harm her, let come what may.”

Chick’s uncertainty was not of long duration.

The man under the steps, if still there, continued to lie low.

Twenty minutes passed, and the watching detective then saw two girls stop at a house nearly a block away. He could see them quite distinctly, the avenue in that locality then being deserted. They parted after a few moments, one entering the house, the other hurrying north. Half a minute brought her nearly to the boarding-house steps—from under which darted a sinister figure that immediately blocked her way.

Chick heard the half-subdued cry of alarm that broke from her, as well as what followed.

“Bart!” she cried, shrinking. “You here!”

“You bet I’m here!” The reply came with a wolfish snarl. “So you’d have let ’em get me, would you?”

“Get you! What do you mean?”

“You know what I mean. You’d have given me to the guns. You know—and I know.”

“Bart——”

“Dry up! Would you blat my name from the housetops? I believe you would do that, you infernal jade.”

The girl shrank from the miscreant’s uplifted hand, from the fierce, threatening look in his fiery eyes.

“Don’t speak to me like that,” she cried, striving to pass him and reach the steps. “Don’t you dare to strike me. I’ll scream for help. I’ll——”

“You open your mouth to scream, hang you, and I’ll close it forever,” Bailey fiercely interrupted. “You’d have given me to the guns. You’d have sent me up——”

“Let me pass!”

“And I’ll send you to the devil for it. I’ll teach you to——”

The miscreant got no farther with his vicious threats.

Chick had seen him reach into his pocket. He had caught the glint of light from a partly drawn blade. He already was nearly across the street, unobserved by either, and he now whipped out his revolver and uttered a shout, though scarce twenty feet from the couple, bent only upon causing Bart Bailey to take to his heels.

“Cut that out!” he shouted. “Let the girl alone, or——”

“Who in thunder are you?[{17}]”