“really great criminals are never found out, for the simple reason that the greatest crimes — their crimes — are never discovered,” remarked professor augustus s. f. x. van dusen positively. “there is genius in the perpetration of crime, mr. grayson, just as there must be in its detection, unless it is the shallow work of a bungler. in this latter case there have been instances where even the police have uncovered the truth. but the expert criminal, the man of genius — the professional, i may say — regards as perfect only that crime which does not and cannot be made to appear a crime at all; therefore one that can never involve him, nor anyone else.”

the financier, j. morgan grayson, regarded this wizened little man of science — the thinking machine — thoughtfully, through the smoke of his cigar.

“it is a strange psychological fact that the casual criminal glories in his crime beforehand, and from one to ten minutes afterward,” the thinking machine continued. “for instance, the man who kills for revenge wants the world to know it is his work; but at the end of ten minutes comes fear, abject terror, and then, paradoxically enough, he will seek to hide his crime and protect himself by some transparent means utterly inadequate, because of what he has said or done in the passion which preceded the act. with fear comes panic, with panic irresponsibility, and then he makes the mistake — hews a pathway which the trained mind follows from motive to a prison cell.

“these are the men who are found out. but there are men of genius, mr. grayson, professionally engaged in crime. we never hear of them, because they are never caught, and we never even suspect them, because they make no mistake — they are men of genius. imagine the great brains of history turned to crime. well, there are today brains as great as any of those which make a profession of it; there is murder and theft and robbery under our noses that we never dream of. if i, for instance, should become an active criminal, can you see —” he paused.

grayson, with a queer expression on his face, puffed steadily at his cigar.

“i could kill you now, here in this room,” the thinking machine went on calmly, “and no one would ever know, never even suspect. why not? because i would make no mistake. in other words, i would immediately take rank with the criminals of genius who are never found out.”

it was not a boast as he said it; it was merely a statement of fact. grayson appeared to be a little startled. where there had been only impatient interest in his manner, there was now something else — fascination, perhaps.

“how would you kill me, for instance?” he inquired curiously.

“with anyone of a dozen poisons, with virulent germs, or even with a knife or revolver,” replied the scientist placidly. “you see, i know how to use poisons; i know how to inoculate with germs; i know how to produce a suicidal appearance perfectly with either a revolver or knife. and i never make mistakes, mr. grayson. in the sciences we must be exact — not approximately so, but absolutely so. we must know. it isn’t like carpentry. a carpenter may make a trivial mistake in a joint, and it will not weaken his house; but if the scientist makes one mistake the whole structure tumbles down. we must know. knowledge is progress. we gain knowledge through observation and logic — inevitable logic. and logic tells us that while two and two make four, it is not only sometimes but all the time.”

grayson flicked the ashes off his cigar thoughtfully, and little wrinkles appeared about his eyes as he stared into the drawn, inscrutable face of the scientist. the enormous, straw yellow head was cushioned against the chair, the squinting, watery blue eyes turned upward, and the slender white fingers at rest, tip to tip. the financier drew a long breath. “i have been informed that you were a remarkable man,” he said at last slowly. “i believe it. quinton fraser, the banker who gave me the letter of introduction to you, told me how you once solved a remarkable mystery, in which —”

“yes, yes,” interrupted the scientist shortly; “the ralston bank burglary — i remember.”

“so i came to you to enlist your aid in something which is more inexplicable than that,” grayson went on hesitatingly. “i know that no fee i might offer would influence you; yet it is a case which —”

“state it,” interrupted the thinking machine again.

“it isn’t a crime — that is, a crime that can be reached by law,” grayson hurried on — “but it has cost me millions, and —”

for one instant the thinking machine lowered his squint eyes to those of his visitor, then raised them again. “millions!” he repeated. “how many?”

“six, eight, perhaps ten,” was the reply. “briefly, there is a leak in my office. my plans become known to others almost by the time i have perfected them. my plans are large; i have millions at stake; and the greatest secrecy is absolutely essential. for years i have been able to preserve this secrecy; but half a dozen times in the last eight weeks my plans have become known, and i have been caught. unless you know the street, you can’t imagine what a tremendous disadvantage it is to have some one know your next move to the minutest detail, and knowing it, defeat you at every turn.”

“no, i don’t know your world of finance, mr. grayson,” remarked the thinking machine. “give me an instance.”

“well, take this last case,” suggested the financier earnestly. “briefly, without technicalities, i had planned to unload the securities of the p., q. & x. railway, protecting myself through brokers, and force the outstanding stock down to a price where other brokers, acting for me, could buy far below the actual value. in this way i intended to get complete control of the stock. but my plans became known, and when i began to unload everything was snapped up by the opposition, with the result that instead of gaining control of the road i lost heavily. the same thing has happened, with variations, half a dozen times.”

“i presume that is strictly honest?” inquired the scientist mildly.

“honest?” repeated grayson. “certainly — of course. it’s business.”

“i shall not pretend to understand all that,” said the thinking machine curtly. “it doesn’t seem to matter, anyway. you want to know where the leak is. is that right?”

“precisely.”

“well, who is in your confidence?”

“no one, except my stenographer.”

“of course, there is an exception. who is he, please?”

“it’s a woman — miss evelyn winthrop. she has been in my employ for six years in the same capacity — more than five years before this leak appeared — and i trust her absolutely.”

“no man knows your business?”

“no,” replied the financier grimly. “i learned years ago that no one could keep my secrets as i do — there are too many temptations — therefore i never mention my plans to anyone — never — to anyone!”

“except your stenographer,” corrected the scientist.

“i work for days, weeks, sometimes months, perfecting plans, and it’s all in my head, not on paper — not a scratch of it,” explained grayson. “therefore, when i say that she is in my confidence i mean that she knows my plans only half an hour or less before the machinery is put into motion. for instance, i planned this p., q. & x. deal. my brokers didn’t know of it; miss winthrop never heard of it until twenty minutes before the stock exchange opened for business. then i dictated to her, as i always do, some short letters of instructions to my agents. that is all she knew of it.”

“you outlined the plan in those letters?”

“no; they merely told my brokers what to do.”

“but a shrewd person, knowing the contents of all those letters, could have learned what you intended to do?”

“yes; but no one person knew the contents of all those letters. no one broker knew what was in the other letters — many of them were unknown to each other. miss winthrop and i were the only two human beings who knew all that was in them.”

the thinking machine sat silent for so long that grayson began to fidget in his chair. “who was in the room besides you and miss winthrop before the letters were sent?” he asked at last.

“no one,” responded grayson emphatically. “for an hour before i dictated those letters, until at least an hour afterward, after my plans had gone to smash, no one entered that room. only she and i work there.”

“but when she finished the letters, she went out?” insisted the thinking machine.

“no,” declared the financier; “she didn’t even leave her desk.”

“or perhaps sent something out — manifolds of the letters?”

“no.”

“or called up a friend on the telephone?” continued the thinking machine quietly.

“nor that,” retorted grayson.

“or signaled to some one through the widow?”

“no,” said the financier again. “she finished the letters, then remained quietly at her desk, reading a book. she didn’t move for two hours.”

the thinking machine lowered his eyes and glared straight into those of the financier. “some one listened at the window?” he went on after a moment.

“no. it is six stories up, fronting the street, and there is no fire escape.”

“or the door?”

“if you knew the arrangement of my offices, you would see how utterly impossible that would be, because —”

“nothing is impossible, mr. grayson,” snapped the scientist abruptly. “it might be improbable, but not impossible. don’t say that — it annoys me exceedingly.” he was silent for a moment. grayson stared at him blankly. “did either you or she answer a call on the phone?”

“no one called; we called no one.”

“any apertures — holes or cracks — in your flooring or walls or ceilings?” demanded the scientist.

“private detectives whom i had employed looked for such an opening, and there was none,” replied grayson.

again the thinking machine was silent for a long time. grayson lighted a fresh cigar and settled back in his chair patiently. faint cobwebby lines began to appear on the domelike brow of the scientist, and slowly the squint eyes were narrowing.

“the letters you wrote were intercepted?” he suggested at last.

“no,” exclaimed grayson flatly. “those letters were sent direct to the brokers by a dozen different methods, and everyone of them had been delivered by five minutes of ten o’clock, when ‘change begins business. the last one left me at ten minutes of ten.”

“dear me! dear me!” the thinking machine arose and paced the length of the room thrice.

“you don’t give me credit for the extraordinary precautions i have taken, particularly in this last p., q. & x. deal,” grayson continued. “i left positively nothing undone to insure absolute secrecy. and miss winthrop i know is innocent of any connection with the affair. the private detectives suspected her at first, as you do, and she was watched in and out of my office for weeks. when she was not under my eyes, she was under the eyes of men to whom i had promised an extravagant sum of money if they found the leak. she didn’t know it then, and doesn’t know it now. i am heartily ashamed of it all, because the investigation proved her absolute loyalty to me. on this last day she was directly under my eyes for two hours; and she didn’t make one movement that i didn’t note, because the thing meant millions to me. that proved beyond all question that it was no fault of hers. what could i do?”

the thinking machine didn’t say. he paused at a window, and for minute after minute stood motionless there, with eyes narrowed down to mere slits.

“i was on the point of discharging miss winthrop,” the financier went on; “but her innocence was so thoroughly proved to me by this last affair that it would have been unjust, and so —”

suddenly the scientist turned upon his visitor. “do you talk in your sleep?” he demanded.

“no,” was the prompt reply. “i had thought of that too. it is beyond all ordinary things, professor. yet there is a leak that is costing me millions.”

“it comes down to this, mr. grayson,” the thinking machine informed him crabbedly enough. “if only you and miss winthrop knew those plans, and no one else, and they did leak, and were not deduced from other things, then either you or she permitted them to leak, intentionally or unintentionally. that is as pure logic as that two and two make four; there is no need to argue it.”

“well, of course, i didn’t,” said grayson.

“then miss winthrop did,” declared the thinking machine finally, positively; “unless we credit the opposition, as you call it, with telepathic gifts hitherto unheard of. by the way, you have referred to the other side only as the opposition. do the same men, the same clique, appear against you all the time, or is it only one man?”

“it’s a clique,” explained the financier, “with millions back of it, headed by ralph matthews, a young man to whom i give credit for being the prime factor against me.” his lips were set sternly.

“why?” demanded the scientist.

“because every time he sees me he grins,” was the reply. grayson seemed suddenly discomfited.

the thinking machine went to a desk, addressed an envelop, folded a sheet of paper, placed it inside, then sealed it. at length he turned back to his visitor. “is miss winthrop at your office now?”

“yes.”

“let us go there, then.”

a few minutes later the eminent financier ushered the eminent scientist into his private office on the street. the only other person there was a young woman — a woman of twenty six or seven, perhaps — who turned, saw grayson, and resumed reading. the financier motioned to a seat. instead of sitting, however, the thinking machine went straight to miss winthrop and extended a sealed envelop to her.

“mr. ralph matthews asked me to hand you this,” he said.

the young woman glanced up into his face frankly, yet with a certain timidity, took the envelop, and turned it curiously in her hand.

“mr. ralph matthews,” she repeated, as if the name was a strange one. “i don’t think i know him.”

the thinking machine stood staring at her aggressively, insolently even, as she opened the envelop and drew out the sheet of paper. there was no expression save surprise — bewilderment, rather — to be read on her face.

“why, it’s a blank sheet!” she remarked, puzzled.

the scientist turned away suddenly toward grayson, who had witnessed the incident with frank astonishment in his eyes. “your telephone a moment, please,” he requested.

“certainly; here,” replied grayson.

“this will do,” remarked the scientist.

he leaned forward over the desk where miss winthrop sat, still gazing at him in a sort of bewilderment, picked up the receiver, and held it to his ear. a few moments later he was talking to hutchinson hatch, reporter.

“i merely wanted to ask you to meet me at my apartments in an hour,” said the scientist. “it is very important.”

that was all. he hung up the receiver, paused for a moment to admire an exquisitely wrought silver box — a “vanity” box — on miss winthrop’s desk, beside the telephone, then took a seat beside grayson and began to discourse almost pleasantly upon the prevailing meteorological conditions. grayson merely stared; miss winthrop continued her reading.

professor augustus s. f. x. van dusen, distinguished scientist, and hutchinson hatch, newspaper reporter, were poking round among the chimney pots and other obstructions on the roof of a skyscraper. far below them the slumber enshrouded city was spread out like a panorama, streets dotted brilliantly with arc lights, and roofs hazily visible through the mists of night. above, the infinite blackness hung like a veil, with star points breaking through here and there.

“here are the wires,” hatch said at last, and he stooped.

the thinking machine knelt on the roof beside him, and for several minutes they remained thus in the darkness, with only the glow of an electric flash to indicate their presence. finally the thinking machine rose.

“that’s the wire you want, mr. hatch,” he said. “i’ll leave the rest of it to you.”

“are you sure?” asked the reporter.

“i am always sure,” was the tart response.

hatch opened a small hand satchel and removed several queerly wrought tools. these he spread on the roof beside him; then, kneeling again, began his work. for half an hour or so he labored in the gloom, with only the electric flash to aid him, and then he arose.

“it’s all right,” he said.

the thinking machine examined the work that had been done, grunted his satisfaction, and together they went to the skylight, leaving a thin, insulated wire behind them stringing along to mark their path. they passed down through the roof, and into the darkness of the hall of the upper story. here the light was extinguished. from far below came the faint echo of a man’s footsteps as the watchman passed through the silent deserted building.

“be careful!” warned the thinking machine.

along the hall to a room in the rear they went, and still the wire trailed behind. at the last door they stopped. the thinking machine fumbled with some keys, then opened the way. here an electric light was going. the room was bare of furniture, the only sign of recent occupancy being a telephone instrument on the wall.

here the thinking machine stopped and stared at the spool of wire which he had permitted to wind off as he walked, and his thin face expressed doubt.

“it wouldn’t be safe,” he said at last, “to leave the wire exposed as we have left it. true, this floor is not occupied; but some one might pass up this way and disturb it. you take the spool, go back to the roof, winding the wire as you go, then swing the spool down to me over the side so i can bring it in the window. that will be best. i will catch it here, and thus there will be nothing to indicate any connection.”

hatch went out quietly and closed the door.

twice the following day the thinking machine spoke to the financier over the telephone. grayson was in his private office, miss winthrop at her desk, when the first call came.

“be careful in answering my questions,” warned the thinking machine when grayson answered. “do you know how long miss winthrop has owned the little silver box which is now on her desk, near the telephone?”

grayson glanced around involuntarily to where the girl sat idly turning over the leaves of her book. “yes,” he answered; “for seven months. i gave it last christmas.”

“ah!” exclaimed the scientist. “that simplifies matters. where did you buy it?”

grayson mentioned the name of a well known jeweler.

“good by,” came the voice of the scientist, and the connection was broken.

considerably later in the day the thinking machine called grayson to the telephone again.

“what make of typewriter does she use?” came the querulous voice over the wire.

grayson named it.

“good by.”

while grayson sat with deeply perplexed lines in his face, the diminutive scientist called upon hutchinson hatch at his office. the reporter was just starting out.

“do you use a typewriter?” demanded the thinking machine.

“yes.”

“what kind?”

“oh, four or five kinds — we have half a dozen varieties in the office. i can use any of them.”

they passed along through the city room, at that moment practically deserted, until finally the watery, blue eyes settled upon a typewriter with the name emblazoned on the front.

“that’s it!” exclaimed the thinking machine. “write something on it,” he directed hatch.

“what shall i write?” inquired the reporter, and he sat down.

“anything you like,” was the terse response. “just write something.”

hatch drew up a chair and rolled off several lines of the immortal practice sentence, beginning, “now is the time for all good men —”

the thinking machine sat beside him, squinting off across the room in deep abstraction, and listening intently. his head was turned away from the reporter, and his ear was within a few inches of the machine. for half a minute he sat there listening, then shook his head.

“strike your vowels,” he commanded; “first slowly, then rapidly.”

again hatch obeyed, while the scientist listened. and again he shook his head. then in turn every make of machine in the office was tested the same way. at the end the thinking machine arose and went his way. there was an expression nearly approaching complete bewilderment on his face, as he went out.

for hour after hour that night the thinking machine half lay in a huge chair in his laboratory, with eyes turned uncompromisingly upward, and an expression of complete concentration on his face. there was no change either in his position or his gaze as minute succeeded minute; the brow was deeply wrinkled now, and the thin line of the lips was drawn taut. the tiny clock in the reception room struck ten, eleven, twelve, and finally one. at just half past one the thinking machine arose suddenly.

“positively i am getting stupid!” he grumbled half aloud. “of course! of course! why couldn’t i have thought of that in the first place!”

so it came about that grayson did not go to his office on the following morning at the usual time. instead, he called again upon the thinking machine in eager, expectant response to a note which had reached him at his home just before he started to his office.

“nothing yet,” said the thinking machine as the financier entered. “but here is something you must do today. what time does the stock exchange close?”

“three o’clock,” was the reply.

“well, at one o’clock,” the scientist went on, “you must issue orders for a gigantic deal of some sort; and you must issue them precisely as you have issued them in the past; there must be no variation. dictate the letters as you have always done to miss winthrop; but don’t send them. when they come to you, keep them until you see me.”

“you mean that the deal must be purely imaginary?” inquired the financier.

“precisely,” was the reply. “but make your instructions circumstantial; give them enough detail to make them absolutely convincing.”

“and hold the letters?”

“hold the letters,” the other repeated. “the leak comes before you receive them. i don’t want to know or have an idea of what mythical deal it is to be; but issue your orders at one o’clock.”

grayson asked a dozen questions, answers to which was curtly denied, then went to his office. the thinking machine again called hatch to the telephone.

“i’ve got it,” he announced briefly. “i want the best telegraph operator you know. bring him along and meet me in the room on the top floor where the telephone is at precisely fifteen minutes of one o’clock today.”

“telegraph operator?” hatch repeated.

“that’s what i said — telegraph operator!” replied the scientist irritably. “good by.”

hatch smiled whimsically at the other end as he heard the receiver banged on the hook — smiled because he knew the eccentric ways of this singular man, whose mind so accurately illuminated every problem to which it was directed. then he went out to the telegraph room and borrowed the principal operator. they were in the little room on the top floor at precisely fifteen minutes of one.

the operator glanced about in astonishment. the room was still unfurnished, save for the telephone box on the wall.

“what do i do?” he asked.

“i’ll tell you when the time comes,” responded the scientist, as he glanced at the watch.

at three minutes of one o’clock he handed a sheet of blank paper to the operator, and gave his final instructions. “hold the telephone receiver to your ear and write on this what you hear,” he directed. “it may be several minutes before you hear anything. when you do, tell me so.”

there was ludicrous mystification on the operator’s face; but he obeyed orders, grinning cheerfully at hatch as he tilted his cigar up to keep the smoke out of his eyes. the thinking machine stood impatiently looking on, watch in hand. hatch didn’t know what was happening; but he was tremendously interested.

and at last the operator heard something. his face became suddenly alert. he continued to listen for a moment, and then came a smile of recognition as he turned to the scientist.

“it’s good old morse, all right,” he announced; “but it’s the queerest sort of sounder i ever read.”

“you mean the morse telegraphic code?” demanded the thinking machine.

“sure,” said the operator.

“write your message.”

within less than ten minutes after miss winthrop had handed over the typewritten letters of instruction to grayson for signature, and while he still sat turning them over in his hands, the door opened and the thinking machine entered. he tossed a folded sheet of paper on the desk before grayson, and went straight to miss winthrop.

“so you did know mr. ralph matthews after all?” he inquired.

the girl arose from her desk, and a flash of some subtle emotion passed over her face. “what do you mean, sir?” she demanded.

“you might as well remove the silver box,” the thinking machine went on mercilessly. “there is no further need of the connection.”

miss winthrop glanced down at the telephone extension on her desk, and her hand darted toward it. the silver “vanity” box was underneath supporting the receiver, so that all the weight was removed from the hook, and the line was open. she snatched the box, the receiver dropped on the hook, and there was a faint tinkle of a bell somewhere below. the thinking machine turned to grayson.

“it was miss winthrop,” he said.

“miss winthrop!” exclaimed grayson, and he arose. “i can’t believe it!”

“it doesn’t really matter whether you believe it or not,” retorted the thinking machine. “but if your doubt is very serious, you might ask her.”

grayson turned toward the girl and took a couple of steps forward. there was more than surprise in his face; there was doubt, and perhaps regret.

“i don’t know what it’s all about,” she protested feebly.

“read the paper i gave you, mr. grayson,” directed the thinking machine coldly. “perhaps that will enlighten her.”

the financier opened the sheet, which had remained folded in his hand, and glanced at what was written there. slowly he read it aloud:

“goldman. — sell ten thousand shares l. & w. at 97. mccracken co. — sell ten thousand shares l. & w., 97.”

he read on down the list, bewildered. then gradually, as he realized the import of what he read, there came a hardening of the lines about his mouth.

“i understand, miss winthrop,” he said at last. “this is the substance of the orders i dictated, and in some way you made them known to persons for whom they were not intended. i don’t know how you did it, of course; but i understand that you did do it, so —” he stepped to the door and opened it with grave courtesy. “you may go now. i am sorry.”

miss winthrop made no plea — merely bowed and went out. grayson stood staring after her for a moment, then turned to the thinking machine and motioned him to a chair. “what happened?” he asked briskly.

“miss winthrop is a tremendously clever woman,” replied the thinking machine. “she neglected to tell you, however, that besides being a stenographer and typewriter she was a telegraph operator as well. she is so expert in each of her lines that she combined the two, if i may say it that way. in other words, in writing on the typewriter, she was clever enough to be able to give the click of the machine the sounding of the morse telegraphic code, so that another telegraph operator who heard her machine could translate it into words.”

grayson sat staring at him incredulously. “i still don’t understand,” he said finally.

“here,” and the thinking machine arose and went to miss winthrop’s desk — “here is an extension telephone with the receiver on the hook. it just happens that the little silver box which you gave miss winthrop is tall enough to support this receiver clear of the hook, and the minute the receiver is off the hook the line is open. when you were at your desk and she was here, you couldn’t see this telephone; therefore it was a simple matter for her to lift the receiver, and place the silver box beneath, thus holding the line open permanently. that being true, the sound of the typewriter would go over the open wire to whoever was listening at the other end, wouldn’t it? then, if that typewriter was made to sound the telegraphic code, and an operator held the receiver at the other end, that operator could read a message written at the same moment your letters were being written. that is all. it requires extreme concentration to do the thing — cleverness.”

“oh, i see!” exclaimed grayson at last.

“when we knew that the leak in your office was not in the usual way,” continued the thinking machine, “we looked for the unusual. first i was inclined to believe that there was a difference in the sounding quality of the various keys as they were struck, and some one was clever enough to read that. i had mr. hatch make experiments, however, which instantly proved that was out of the question — unless this typewriter had been tuned, i may say. the logic of the thing had convinced me meanwhile that the leak must be by way of the telephone line, and mr. hatch and i tapped it one night. he is an electrician. then i saw the possibility of holding the line open, as i explained; but for hour after hour the actual method of communication eluded me. at last i found it — the telegraphic code. then it was all simple.

“when i telephoned to you to find out how long miss winthrop had had the silver box, and you said seven months, i knew that it was always at hand; when i asked you where you got it, i went there and saw a duplicate. there i measured the box and tested my belief that it would just support the receiver clear of the hook. when i requested you to dictate those orders today at one o’clock, i had a telegraph operator listening at a telephone on the top floor of this building. there is nothing very mysterious about it, after all — it’s merely clever.”

“clever!” repeated grayson, and his jaws snapped. “it is more than that. why, it’s criminal! she should be prosecuted.”

“i shouldn’t advise that, mr. grayson,” returned the scientist coldly. “if it is honest — merely business — to juggle stocks as you told me you did, this is no more dishonest. and besides, remember that miss winthrop is backed by the people who have made millions out of you, and — well, i wouldn’t prosecute. it is betrayal of trust, certainly; but —” he arose as if that was all, and started toward the door. “i would advise you, if you want to stop the leak, to discharge the person in charge of your office exchange here,” he said.

“was she in on the scheme?” demanded grayson. he rushed out of the private office into the main office. at the door he met a clerk coming in.

“where is miss mitchell?” demanded the financier hotly.

“i was just coming to tell you that she went out with miss winthrop just now without giving any explanation,” replied the clerk. “the telephone is without an attendant.”

“good day, mr. grayson,” said the thinking machine.

the financier nodded his thanks, then stalked back into his room, banging the door behind him.

in the course of time the thinking machine received a check for ten thousand dollars, signed, “j. morgan grayson.” he glared at it for a little while, then indorsed it in a crabbed hand, “pay to trustees home for crippled children,” and sent martha out to mail it.