The Sign at Six

by Stewart Edward White

  CHAPTER XVI

  THE PROFESSOR'S EXPERIMENT

  Throughout all this excitement Percy Darrow did absolutely nothing. Hespent all his time, save that required for meals and the shortestnecessary sleep, in a round-armed wooden chair in the wireless station ofthe Atlas Building. Jack Warford sat with him. Darrow rarely opened hismouth for speech, but smoked slowly a few cigarettes, and rolled manymore, which he held unlighted in the corner of his mouth until theydropped to pieces. He watched quietly all that went on; glanced throughsuch messages as came in from Monsieur X, read the papers, and dozed. Toreporters he was affable enough in his drawling slow fashion, but hadnothing to say.

  "Eldridge is doing this," he said to them; "I'm only in the position of aninterested spectator."

  Eldridge had taken hold in a thoroughly competent way. Back of the coldprecision of his undoubted scientific attainments lurked, unexpected bymost, a strong ambition and a less admirable hankering for the lime-light.His opportunity to gratify all these appetites--science, advancement, andfame--was too good not to cause him the deepest satisfaction.

  "I have determined," he told the reporters, "that this particularinstrument alone receives the messages from the unknown perpetrator. Ourinvestigations must be initiated, therefore, in this apartment."

  "How do you explain it?" asked one of the reporters.

  "I can not explain it scientifically," admitted Eldridge, "but I cansurmise that the fact either purposely or accidentally has to do eitherwith this instrument's location or with some slight and undeterminedpeculiarity of its tuning."

  "You could easily tell which by moving the instrument to another stationwhere they aren't getting the messages now," suggested Darrow lazily.

  "Certainly," snapped Eldridge, "any child could deduce that. But I fail tosee the use or necessity for the determination at all unless in a spiritof frivolous play. Our task is not to discover where the messages can bereceived, but whence they are sent."

  He gazed frostily at the man who had interrupted him. Darrow smiled softlyback.

  "How far will your instrument carry in sending?" Eldridge asked Simmons.

  "Its extreme is about two hundred miles."

  "Then we can safely assume that a circle drawn with a two-hundred-mileradius would contain this man you call Monsieur X"--the newspapers hadadopted Darrow's nickname for the Unknown--"since you have succeeded incommunicating with him."

  "Marvelous," said Darrow to Jack--but under his breath.

  "As the sending of Monsieur X is faint, it follows that he is somewherenear the periphery of this circle, or that he is possessed of a primitiveor weak instrument. By the doctrine of probabilities we should bejustified in concluding against the latter supposition."

  "How's that, Professor?" asked the _Morning Register_ man. "It doesn't getto me."

  "He is evidently a man not only of scientific attainments, but of immensescientific possessions--as is evidenced by these phenomenal results he isable to accomplish. But we are not justified in reasoning according to thedoctrine of probabilities. Therefore, we shall proceed methodically. Ihave already made my preparations."

  Eldridge looked about him with an air of triumph.

  "I am fortunate enough to have, in the present crisis, unlimited financialbacking," he said. "Therefore, I am in a position to carry out the mostexhaustive of experiments."

  He stretched his hand out for a long roll, which he laid flat upon thetable, pinning down the corners.

  "Here is a map of the Eastern States," said he. "I have drawn a circle onit with a two-hundred-miles radius. At this moment a private instrumentwith a full crew to string sending and receiving wires is two hundredmiles from here on the New York Central Railroad. It has for itstransportation a private train, and it will be given a clear right ofway." He turned to Simmons. "Have you found yourself able to communicatewith this Monsieur X at any time?"

  "Communicate!" echoed Simmons. "Why, he's easier to talk to than a girlwho wants an ice-cream soda!"

  "Then send this: 'Your messages have been communicated to the people. Bepatient.'"

  Simmons touched the key. The spark leaped crashing.

  "What do you get?" asked Eldridge, after a moment.

  "Oh, a lot of the same sort of dope," answered Simmons wearily. "Do youwant it?"

  "No, it is not necessary," replied Eldridge. "But listen for anothermessage from about the same distance when he has finished."

  Silence fell on the room. At the end of ten minutes Simmons raised hishead.

  "I get 'O K Q' over and over," said he. "Want that?"

  "That," replied Eldridge with satisfaction, "indicates that my crew on thespecial train in the Adirondacks two hundred miles away has heard yourmessage to Monsieur X." He glanced at his watch. "Now, if you would be sogood as to afford me a moment's assistance," he requested Simmons, "I wishto disconnect from your battery one of your powerful Leyden jars, and tosubstitute for it one of weaker voltage. I ventured to instruct mydelivery man to leave a few in the outer hall."

  "That will weaken the sending power of my instrument," objected Simmons.

  "Exactly what I wish to do," replied Eldridge.

  "He's clever all right," Darrow murmured admiringly to Jack. "See whathe's up to?"

  "Not yet," muttered Jack.

  The substitution completed, Eldridge again glanced at his watch.

  "Now," he instructed Simmons, "send the letters 'Q E D,' and continue todo so until you again hear the letters 'O K Q.'"

  Simmons set himself to the task. It was a long one. At last he reportedhis answer.

  "He sends 'O K Q ten,'" he said.

  Eldridge turned to the reporters.

  "That means that the substitution of the smaller Leyden jar for one of thelarger reduced the sending power of this instrument just ten miles," saidhe. "My crew has quite simply moved slowly forward until it caught oursending here."

  "Next," he instructed Simmons, "see if you can communicate with MonsieurX."

  The operator speedily reported his success at that. Eldridge removed hisglasses and polished their lenses.

  "Thus, gentlemen," said he, "from our circle of two-hundred-mile radius wehave eliminated a strip ten miles wide. Naturally if this weakened sendingreaches only one hundred and ninety miles, and our antagonist receives ourmessages, he must be nearer than one hundred and ninety miles. We will nowfurther reduce the strength of our sending and try again."

  The younger men present broke into a shout,

  "Good work!" somebody cried. They crowded about, keenly interested in thisnew method of man-hunting. Only Darrow, tipped back in his chair againstthe wall, seemed unexcited.

  To Jack's whispered question he shook his head.

  "It's ingenious," he acknowledged, "but he's on the wrong track." That wasas far as he would explain, and soon dropped into a slight doze.

  Throughout the greater part of the night the experiment continued. Batteryby battery the sending power of the instrument was weakened. Mile by milethe special train drew nearer until, by catching the prearranged signal,it determined just how far the new sending reached. Then Simmons triedMonsieur X. As the latter invariably answered, it was, of course, evidentthat he remained still in the narrowing zone of communication. It wasfascinating work, like the drawing of a huge invisible net.

  The reporters on the morning papers mastered only with difficulty theirinclination to stay. They had to leave before their papers went to press,but were back again in an hour, unwilling to lose a moment of the game. Atension vibrated the little office. Only Percy Darrow dozed alone in thecorner, leaning back in his wooden armchair.

  At near four o'clock in the morning Simmons raised his head after a longbout of calling to announce that he could get no reply from Monsieur X.

  "He's got tired of your fool messages," remarked the _Register_ man. "AndI don't wonder! Guess he's gone to bed."

  Eldridge said nothing, but replaced the Leyden jar he had but justremoved.

  "Try one," said
he.

  "I get him," reported Simmons, after a moment.

  "Send him anything plausible and reassuring," commanded Eldridge hastily.He turned to his small and attentive audience in triumph. "Thus,gentlemen," he announced, "we have proven conclusively that our man islocated between forty and fifty miles from New York. If we draw twocircles, with this building as center, the circumference of one of whichis fifty, the other forty miles away, we define the territory within whichthe malefactor in question is to be found."

  The people in the room crowded close about the table to examine the mapupon which Professor Eldridge had drawn the circles.

  "There's an awful lot of country--some of it pretty wild," objected the_Bulletin_ man. "It will be a long job to hunt a man down in thatterritory."

  "Even if it were as extensive a task as a hasty review of the facts mightindicate," stated Eldridge, "I venture to assert that enough men would beforthcoming to expedite such a search. But modifying circumstances willlighten the task."

  "How's that?" asked the _Banner_ man, speaking for the others' evidentinterest.

  "We have no means of surmising the method by which this man succeeds inarresting vibratory motions of certain wave-lengths," said Eldridgedidactically, "any more than we are able to define the precise nature ofelectricity. But, as in the case of electricity, we can observe the actionof its phenomena. Two salient features leap out at us: one is that thesephenomena are limited in time; the other that they are limited in space.The latter aspect we will examine, if you please, gentlemen.

  "The phenomena have been directed with great accuracy (a) at the AtlasBuilding; (b) at this city and some of its immediate suburbs. Thepeculiarity of this can not but strike an observant mind. How is this manable, at forty or fifty miles distance, to concentrate his efforts on onecomparatively small objective? We can only surmise some system ofinsulating screens or focal mirrors. I might remark in passing that theexistence of this power to direct or focus the more rapid etherealvibrations would be a discovery of considerable scientific moment. But ifthis is the method employed, why do we not cut a band of vibratorynullifications, rather than touch upon a focal point?"

  "Repeat softly," murmured the irrepressible _Register_ man.

  "Why," explained Eldridge patiently, "are not the people and buildingsbetween here and the unknown operator affected? The only hypothesis we arejustified in working upon is that the man's apparatus is at a heightsufficient to carry over intervening obstacles. This hypothesis isstrengthened by the collateral fact that the territory we have justdetermined as that within which he must be found lies in the highlands ofour own and neighboring states. We may, therefore, eliminate the low-lyingdistricts within our radius."

  Percy Darrow opened one eye.

  "Perhaps he's up in a balloon," he drawled languidly; "better take alongan aeroplane."

  Eldridge cast on him a look of cold scorn. Darrow closed the eye.