*** START OF THE PROJECT GUTENBERG EBOOK 53214 *** THE MYSTERY OF THE FIFTEEN SOUNDS By Van Powell [Illustration: Title page graphic] The Goldsmith Publishing Company CHICAGO Copyright 1937 by The Goldsmith Publishing Company MANUFACTURED IN THE UNITED STATES OF AMERICA FOREWORD "_No wonder I'm blue," Roger told his father, "You're packing to head a museum expedition into the heart of Borneo._ You'll _have thrills_." "_Probably I will get my sort of excitement in plenty, Roger. It won't be what you are always dreaming about--the 'good old days' of Pirates and Cowboys and Stage-Coach Bandits._" _"No," Roger agreed, "the real thrills are all gone. But you can go on an expedition, instead of having school and_----" "_There will be vacation time--baseball_----" "_But I want real excitement. I'd like to be a Modern Pioneer. You are one, going off to Borneo for the museum just the way Columbus set out for Queen Isabella._" _His father looked up._ "_You can be a Modern Pioneer. I will show you a House of Mystery, and once you step into its door you are in a land where there are more exciting activities packed into one day than you could get being a combination cow-hand, bad man, pirate and pony express rider. You may not be able to convoy an ox-team across a prairie, carry a squirrel gun and stand off scalping Sioux; but you will help battle against Pirate Fire, and Bad Man Erosion, and Bandit Microbe._" "_You mean--work in cousin Grover's research lab?_" _That was it, he found. And under the brilliant training of his older cousin, as he came to be the supply clerk and learned more about the work of the active place, Roger saw how truly his father had spoken._ _There was fun, and mystery, and excitement, even in the work. Also, there was the feeling of being a Modern Pioneer, one who belonged to the band that had substituted electricity and wings for ox-wagon and candles, who gave the world instead of the pony rider carrying news, the radio and radio-telephone. Science was the Modern Pioneer._ _Where their forefathers sought new borderlands, these modern way-showers explore the stratosphere. As their trail-blazing ancestors fought Indians and hardship and poor crops, these men battle against disease germs, and soil erosion, and eye-straining light and every other detriment to safer, happier existence._ _As great as the feat of Columbus, Roger found the announcement that a cure had been found for a terrible disease._ _On a par with Daniel Boone's fame was the renown of the research worker who extended the range of compact radio receivers._ _In such privately owned laboratories as that of his cousin, Grover Brown, and in those associated with universities and colleges and other institutions, the work of the Modern Pioneers went on._ _They loved it, found adventure in it, and joy of achievement._ _Not always was there the sort of mystery usually read about in detective stories; but when such problems did come up, Roger realized how the equipment of scientific research could be a useful aid to the clever deductive brain in solving the puzzle._ _It is to show how much of adventure and thrill, excitement and romance can hide behind electrical transformers and tubes of germs, bags of sodium carbonate and humming motors that this experience of a boy in a scientific research laboratory is offered. Perhaps some boy, who has almost decided that the only "real" life involves guns and "rackets," will be shown how the useful life of the fellow who fights for humanity and not against it brings more thrill and joy and contentment than any of the risky, falsely stimulating adventures that only lead to discredit, sorrow and punishment._ Van Powell NOTE Names used in this story are purely fictitious and if any name is like that of a real person it is coincidence and no libel or aspersion on character is intended or implied. However, every scientific device, process and theory herein is based on electrical, chemical and other data of developed apparatus and procedure or on theories so far perfected as to be acceptable to Science. Contents PAGE Foreword 9 CHAPTERS 1. "Them Mouses Is Extraverted!" 17 2. A Creeping Thing! 23 3. A "Sound" Clue 29 4. An Electrical Trap 38 5. What Electricity Could Not Catch 44 6. A Weird Story 52 7. Science to the Rescue 60 8. Basketball and Brains 66 9. The Voice in the Silence 72 10. A Defeat for Science! 78 11. A Puzzling Thump 84 12. Detective Roger 90 13. Scientist Roger 97 14. Captive Roger 102 15. In the Lamasery 107 16. The Image Speaks 113 17. Black Silence 117 18. A Letter Roger Had Not Sent 121 19. Disquieting Deductions 127 20. Ghost Voices 131 21. Tragedy! 137 22. What Happened to the Eye of Om 143 23. The Acid Test 147 24. An Impossible Camera "Shot" 151 25. Score One for the Mystery Wizard 154 26. Roger Lists His Clues 159 27. A "Thermal" Trick 166 28. The Fuse 172 29. A Surprising Capture 176 30. The Voiceless Warning 184 31. The Hidden Menace 188 32. Science Fights Craft 191 33. A New Suspicion 195 34. Tragedy Strikes Again 201 35. The Stalking Terror 206 36. A Law of Nature 212 37. Revelation! 217 38. The Vigil 223 39. The Ape and the Kangaroo 227 40. The Mystery Wizard's Solution 235 41. Man and Beast 241 42. Closing Time 246 Chapter 1 "THEM MOUSES IS EXTRAVERTED!" Something was wrong at the laboratory! Ringing bells, long before dawn, awakened Roger Brown. Dazed at first, he became alert as a strange, cold foreboding made him leap out of bed. "Just the telephone," his thirty year old cousin, head of the laboratory, called from his room beyond the adjoining bath. Roger, who was already on his way to the downstairs library of his cousin's home, paused. "No!" Well built and athletic, sharp-eyed, keen minded, a worthy student under his brilliant scientific cousin, Roger spoke earnestly, "It wasn't just the protective beam system, or just the fire alarm, either. Grover, it was _both_!" "Impossible! Why have they stopped ringing?" Tying his robe cord, the older cousin followed Roger. He knew that "Ear Detective's" reputation for reading sounds, even if his own incisive reasoning made him feel that this time Roger had been too drowsy to live up to his nickname. Just the same, he followed. "As long as the beam was broken," he insisted, "The bells ought to continue to ring. I think your fame as a sound interpreter is done." Roger did not try to defend himself. "It was probably a wrong number on the telephone." Grover was five steps behind his younger relative, "If you are so sure it was our alarm system, especially both bells, why aren't you dressing to rush to the lab?" "I'm getting down to be ready when Tip calls." Potiphar Potts, nicknamed Tip, was handy man at the scientific research plant. He slept there. In a moment Roger expected to have him call up to report the reason for the alarm. "You will never hold your reputation now." Grover turned at the library door as Roger, inside, stared, baffled, at the annunciator panel. The reputation his cousin spoke about had come when a chemist, sent to them to help the laboratory develop a new series of dyes for a textile mill, had begun to "hear things." Deaf, wearing an Amplivox, composed of a chest microphone, batteries and an ear piece, the man had been nearly crazed by a persecuting, accusing voice picked up, it seemed, by his device. Roger, by identifying an odd click he got in a makeshift imitation Amplivox set, gave Grover the clue through which a revengeful enemy who had sought to terrify the man had been discovered. As The Ear Detective, Roger, who was in charge of the laboratory stock-room, had really been the means of solving the mystery. "I know I heard the laboratory bells," Roger insisted. "But the lights on our tell-tale are not lit." "I can't help it. Both the fire alarm bell and the system that warns us if anybody enters----" "But Potts has not called up, either. Go back to bed." Grover turned to leave the room. Roger, who was staying with his cousin while his own father headed an exploring expedition into Borneo for a museum, knew that his ears had not betrayed him. His cousin, several years before, had secured capital with which to start a scientific research laboratory for the use of small companies unable to maintain equipment and an expensive staff. Every form of research, electrical, chemical, industrial, and in one instance medical, had been successfully undertaken. The "lab" prospered, and enjoyed a reputation for scientific and human thoroughness and dependability. Priceless secrets, formulae, data and results were always in the laboratory, and its owner had devised seemingly perfect methods for safeguarding the secrets which rivals, or competing firms, might covet. A completed series of experiments to find a synthetic substitute for camphor gum, an industrial formula almost beyond price, was reposing in the safe on this early morning of Spring. The safeguards comprised two: There was a series of light-beams, interconnected with microphones and tiny speed cameras, at every possible entrance. Any broken beam, telling of wrongful entry, set off a laboratory bell in the room where Potts slept; and it also was wired to ring a bell at the owner's home; and on a panel, numbered lights would show, by the one that glowed, which entrance had been used. To protect the laboratory from fire, and warn of its existence, a bell of a higher tone with a thermostat connection in the laboratory, in each section, would give warning; and if the blaze was in the cellar, a green bulb would glow; if in the main floor, a red bulb, and for the upper section a blue bulb would be lit. Naturally, Grover felt that his younger cousin had mistaken the sound that had awakened both. Roger, still feeling his weird and unexplainable sense of hidden danger, picked up the telephone. The laboratory, when he dialed repeatedly and waited long, did not respond. Tip, trusted, loyal, paid extra salary because he was counted on not to leave the mechanical devices to give the sole protection, should have answered his extension telephone. "I tell you there is something wrong," insisted Roger. His cousin, partly convinced, taking on some of Roger's concern, began to dress. Just as he came down Roger knotted his tie. In the car kept handy in the garage, they drove the several blocks to the two-story building. Before they got near it, Grover put on speed. Fire sirens and the scream of the warning signal on a police car made both cousins wonder what terrible situation they might face. Had some one, entering the laboratory, set off the first alarm as fire broke out? Had Potts, fighting either fire or intruder, been rendered incapable of responding to their telephone call? "Oh, I hope nothing has happened to Tip." Roger was very fond of the dull-witted, but dependable man, almost an Albino with his sandy hair and light eyes, who loved to use big words whether they fitted his idea or not, and who helped in the many mechanical, photographic and other activities involved in their work. The car, racing forward, turned into the proper street and they saw fire apparatus gathering in front of the building. Roger, as the car slowed, leaped out, crouching and running to avoid being thrown down by the momentum. "Don't break in!" he shouted to firemen, "Our protective gas will prevent damage--and water would ruin our electrical things." The company captain paused as he saw, behind the youthful caller, the taller laboratory owner striding forward. His men, with a battering ram, delayed. The helmeted men, some with axes, others with scaling ladders, hose, or the rubber covers used by the emergency squad from the Fire Underwriters, paused. "What-da-ya mean, nothing more won't burn?" growled a policeman from the patrol car standing nearby. His finger pointed toward the glass panel of the main door. Roger, looking in, saw the curious orange glow and the weirdly bluish-violet splaying out across the office from the inner spaces. "Who--what set off the flouroscope and the X-rays?" he gasped, while Grover reassured the gathered people. Unobtrusively setting one foot well to the side on the top step, so that his toe, pressed forward, found the small protecting pin, he unlocked the door, careful to keep the knob turned toward the left, instead of in the natural hand-turn to the right. That, Roger knew, cut out that particular light-beam system, so that they could enter without altering the present status of the tell-tale panel inside that would reveal where entry had been made, and by which magnetized plate the marauder would be held in trying to escape. They rushed in. His first rush took Roger to the panel. Not a bulb glowed! He stared, unable to accept the story it told--somebody had set off every light-beam-trip! That put out the lights. Not one of the row connected-in with the magnetized plates was lit, either, and yet no living person should have walked or crept or climbed away through door, window, coal-chute or other exit without getting caught. But Roger did not pause. He ran to Tip's room. Tip, tied tightly to a bedpost, his lips taped shut, his eyes rolling as he sweated in his frantic effort to escape, saw him. Roger first took the tape off as gently as haste allowed. Just as soon as he was able to speak, Tip gasped: "Tell Grover them mouses ain't is." "Ain't _is?_----" He knew that Potts used queer phrases, trying to fit big words in, and this might be his way of leading up to some puzzling declaration. "What happened? Stop being smart, and tell me!" ordered Roger. "If mouses is here, you say they _is_ here?" "Well?----" "They ain't is." "Gone?" Roger stared, "The white rats. Gone?" "They done extraverted." Roger had to study that out. He knew that the psychological word was used by analysts of human minds to indicate people whose outlook on life was normal, while introverts were shy, timid people who were afraid of life. "Extraverted" must mean that the animals had turned outward toward the world--run away, or escaped. "But those white rats--Doctor Ryder's--were in a cage with a trap door on top, and they'd been inoculated with cultures of a spinal disease," cried Roger. "How do you know?" "I was up lookin' at 'em, and somethin' with a hand like a ham hit me back of the ears, and when I come to, tied, them rats was evacuated. I was drug down here by a ape and tied. An' there was somethin' else I didn't get a look at, behind the ape." Was the man crazed? It worried Roger. But a call from Grover, upstairs, quickly told him that Potts had not been talking wildly. "Roger," called his cousin, "The white rats' cage is empty!" Chapter 2 A CREEPING THING! It took Roger a moment only to realize the enormous danger that was behind the loss of those inoculated rats. When Doctor Ryder had been allotted space in which to conduct his experiments to see if he could perfect a cure for a horribly deadly spinal affliction, he had decided to experiment, first, on animals. Such experiments had been gotten under way the night before. The rats, inoculated, were carriers of the deadly germs. If some ignorant person had taken them, and the public was not warned to be careful, anything might happen! One of Grover's constantly repeated axioms about laboratory work was: "Do the first thing first!" All life, the scientific student always had insisted, was like the chemical compounds they handled. No matter what the problem might be, no matter how it looked, it could be analyzed the way compounds would be analyzed, the elements could be isolated, and the base--the guide to the whole condition--could be known. Sodium, a metal, very unstable, combined with chlorine, a gas, turned into sodium chloride, and that was a salt--common table salt, in fact. Yet the restrainer used in photography, a dissolved salt, was sodium bromide, another gas and the metal, and to find out what a compound held, one had to separate all parts by test and find the base or original element. But first, one must do the first thing--and in this situation Roger knew that the first thing was to get busy on the telephone. White rats had been inoculated with dangerous germs. A bite from such an animal was ten times more terrible than that of a plain rat, poisonous though that would be. Therefore, if those inoculated animals were now missing, Grover, up where their cage had been, would know it already; but the public, exposed to possible contamination, must be warned. Roger plugged in the upstairs telephone so that the policeman could reach his headquarters and start a widespread search of all cars on the roads, all suspicious people carrying sacks or other possible packages or cases that could hide the rats. The Health Department and news and radio agencies must be asked to broadcast public warnings. And the owner of the rats, Doctor Ryder, should be called. Therefore, when Roger went upstairs, his report made his cousin nod approvingly. Roger had done all he could to avert danger if the rats had been taken ignorantly by some idiot who might let one or more escape and spread disease germs. With his story told, Potts was busy doing what Grover had ordered as one way to secure clues: a motion picture camera using non-flam film, flashbulbs of the latest type, tripod for time exposing, and both wide-angle and micrometric lenses, to give large views of big spaces or vastly magnified details of practically invisible things, formed the kit that the handy man worked with. Because he had used his wit Grover had no orders for Roger as the firemen, police and officers departed. Nothing could be done until Potts developed his "takes" so they could be run in the laboratory screening-room. Grover, in his small, private "thinking den," would want to be left to think out and separate all the mysteries, so that he could get to the heart of the affair and thus decide what to do about it. Alone, wide-awake, with the dawn just beginning to lighten the skylight in the roof over his stock-room, Roger stood thinking. He knew that if the small, partitioned space set aside for Doctor Ryder had held clues, Grover would have told him. The germs supposed to have been injected into rats the night before could not have produced much effect that past night. The doctor had not felt that he had to observe, personally, as he would have done later. Instead, automatic "observers" had been set up. Inside the empty cage, a dictagraph microphone showed, fixed to the glass inside the cage top. That, Roger knew, led to a device like the seismograph which registers earthquake tremors. Its purpose was to show, by the vibration of a pen across a moving tape, when the rats developed any unusual excitement or stress, which was not expected but was provided for in that way. A camera of the moving picture type, but set to snap one take at minute intervals, would check also; and if the seismograph got to zig-zagging sharply, it would make contact on one side with a relay, and throw on the "continuous" mechanism of the marvelous camera. To discover by calculating how much of the tape had been unreeled when something had stopped it, was easy; and in that way Roger knew the time that the mechanism had stopped, although he did not dare fix that as the time the rats had vanished, because the tape had started at five in the afternoon, and had unreeled to the point to show that it had stopped at four in the morning; but the alarm had not sounded until half an hour or so later. The tape showed excited swerves of the recording stylus, but not apparently enough to start the continuous takes, because Grover had left the magazine as it was until Potts should be ready to develop all prints at one time. With his snapshots and time exposures of wide-angles of windows, doors, floors, air-conditioning intake, exhaust, cellar openings and floors, and his micrometric detail close-ups of parts of all these, Potts went to the dark-room adjoining Roger's stock-room. The film he had taken would fill all tanks, so he left the other till later. The authorities had been warned; and nothing more could be done. Roger, as the sun rose, telephoned for light breakfast to be sent from a nearby restaurant, taking Potts his share in the dark-room. As he ate, Roger tried to bring some sense into the baffling set of conditions: The white rats, in their cage, with the observation apparatus and chart with notations, should have been recognized by anybody who could see and who could read, as dangerous to handle, much more to remove. With the protecting system set, it should have been impossible to enter, at all, and more impossible to get out. Yet the rats had not by any magic been evaporated into thin air. Furthermore, Roger mused, why had the fluoroscope and X-ray machinery been put into operation? The entire situation seemed to be too bizarre to be true: more than all the rest, the mad story of Potts that he had felt a hand as "big as a ham," hit him before he had lost his senses! Nothing fitted anything else. Doctor Ryder, arriving, was as much a contrast to cold, unexcited Grover as could be imagined. He sputtered his fears for the public, his dismay that this should have brought discredit on the laboratory that had been known to safeguard its precious data. Roger, watching the pudgy, stout little germ experimenter who excitedly mixed wild theories with wilder plans of procedure, thought to himself that if anybody or anything would upset his cousin, the man's emotional excitement would be the thing. Grover was not stirred out of his quiet manner. The staff began to arrive. They had all seen in newspapers or had heard by radio the warnings and the brief story of the lost rats. Mr. Millman, the electrical engineer, asked immediately of Dr. Ryder: "Have you any enemies?" The experimenter thought that he might have antagonists among the scientists who disagreed with his theories; but they would not be men who would endanger the public for so small a revenge as could come from criticism of his laxness in not watching his experiment more closely. Mr. Ellison, the laboratory's electrical research specialist who worked with Mr. Millman, agreed; and so did the bio-chemist, Mr. Zendt; the analytical chemist, Mr. Hope, and Grover. They were discussing the many contradictory and unexplainable points when Potts called, from the darkroom: "Hi, Rog'--come quick!" As soon as his eyes were accustomed to the dull rosy glow after he passed the light-trap, Roger saw Tip clipping non-flam film positives to drying drums. "What have you got, Tip?" "Look!" Potts snapped a strip in place in a vision tunnel: Roger applied his eye to the lens, and saw, enlarged on the viewing-plate, what appeared to be the edge of a cellar step. With side-lighting, magnified ridges and depressions in dust looked like a range of hills and vales. "It was a snake!" "A--did you say 'snake'?" Roger gasped, "How do you get that?" Potts changed films under Roger's gaze; an enlarged wide-angle of several steps was before his eyes, and the snake-slide of some body that had dragged across just the step-edges, and had made no track of hand or foot on the level of the steps showed! "It certainly looks like something that creeps, Tip." "Well, a snake creeps. A snake! What else?" Chapter 3 A "SOUND" CLUE Without waiting for the gelatin to harden, Roger summoned the staff and his cousin to the screening room. As soon as they had set their wrist watches with the observatory time signals, a routine part of the staff's accuracy, they joined him. He had the tender emulsion-covered celluloid threaded from the top magazine through film gate and take-up sprockets down to the lower magazine of the projector. In the small, compact theatre, with its platform for lecture and demonstration procedure, its large screen, easy chairs, loud speakers and apparatus, he showed Grover and the men what caused him to agree with Tip. "It almost has to be a snake," Roger declared. No other than a creeping thing could drag over a step edge. Four footed creatures, he explained, did not disturb dust at the point indicated in close-up and wide-angle pictures, greatly enlarged by the projector. The chief electrical specialist, Mr. Ellison, agreed. "It ends the mystery. A snake ate the rats." "Then there won't be any disease epidemic," Doctor Ryder was much relieved, "It will crawl somewhere and the germs may destroy the reptile." To this Mr. Millman, electrical engineer; Mr. Zendt, bio-chemist; Mr. Hope, their analyst, and others, agreed. Roger saw that his cousin reserved opinion. But routine had to go forward, and the staff men separated. Zendt went to resume experiments in the search for a dye of a certain desired shade and quality: the two electrical men were busy developing means to find a better way to insulate high-tension cable for carrying electricity from generators to distributing stations in small communities; the others had equally absorbing work in progress. Grover, busy examining each picture projected and held on the screen without danger of the "cold" light igniting the protected film, gave Roger a dozen cellar views around the coal-chute to enlarge. "Make ten-by-twelve bromide enlargement prints," he ordered. Roger, although it seemed impossible that anyone could have moved the stiff rusted bolt inside the trapdoor of the coal chute, a trap that lifted up and out onto the street, said no word of objection. He felt that Grover would find nothing in the enlargements. Expertly he adjusted paper on the camera-stand, extended the bellows to secure most perfect focus, made his exposures, developed, and fixed the large prints, and took them to his cousin's own den. "As I expected--nothing!" he reported. "No abrasions of the bolt, or edge of the trap?" "You mean, where someone inserted a 'jimmy' to shove back the bolt?" Grover nodded. "Not a thing shows." Roger asserted. His cousin did not accept his statement; but his disappointed eyes told Roger that the examination he had made during developing work had been accurate, thorough, and had led to a correct decision. They were at a standstill. Calls to the zoo, brought from its curator the declaration that no snake was absent from its cage, that no one of his keepers had tried to "train" snakes--as the laboratory head had half-laughingly suggested. As he left the screening room, Roger met Potts. "Tip," he hailed, "Did you get anything on the 'sound' film in the one-snap-a-minute camera?" "The one that took pictures of them mouses?" "The one by the rats' cage--yes." "You know about sound, Rog'. It ain't just a lot of single pictures." Potts wanted to air his knowledge. "Sound is a maintained concession of peaks an' valleys on the sound track." "You always will use a .44 caliber word when a BB. size would hit what you aim at and not blow your idea to bits, Tip. You mean that sound is a 'sustained succession'--I know that. And single frames, if they showed any sound impression at all, would give little pops." "So I didn't bother." "But, Tip! There was a lot of wild zig-zag marking on the tape in the seismograph-like recorder; and it seemed as though the 'continuous' taking lever had been shifted before he--it--whatever was there, stopped the whole business by breaking off the wiring." "We can try." When they had developed the negative, made a print and fixed and washed it, Roger threaded the fifteen frames of continuous shots in place and projected with the speakers cut in. Then he rushed to get Grover. The staff too! He had a clue. As nearly as he could have described the brief sound made and amplified with transformer-coupled, matched metal audio tubes of the most perfect type giving the speakers power, they had picked up a sound of hot grease sputtering, hissing and clicking, as it does if sausage is fried rapidly. "Come on, Ear Detective," chaffed Mr. Millman, "Who was frizzling sausages on the cage full of inoculated rats, so that the mike inside picked it up and took it on to the sound film?" "That's not sausage frying," exclaimed the biochemist, "Someone had steam up and the mike picked up the sound the radiator valve made as air was expelled and steam arrived to close it spasmodically." "A microphone, inside of a glass cage top?" mocked Mr. Ellison. "How could a valve on a radiator across the room make all that noise?" "Let the Ear Detective explain it," urged Mr. Hope. They all turned to Roger. He shook his head. "It does sound most like the snick-snap, and sizzle, of sausage," he admitted, "But----" "It's a snake, I say," Potts defended his theory; "a snake, with hissing and his scales rattling on the glass when he was crawling up to dig his head in and grab breakfast." "What's your idea, Grover?" asked Mr. Hope. "Sounds as much like a snake as anything I can imagine, Sam." "So say I," agreed Mr. Ellison. "Are we right, interpreter?" Potts got the correct word, for once. Roger hesitated. Not that he cared if he lost his reputation as a young person able to read correctly what his sensitive ears caught; Roger was not vain or self-satisfied. He was not the sort to make a statement just to hold up his reputation. In some ways the sound might be such as a snake, with its hide striking or rubbing, as it hissed, could make; but, again, a lizard might make that sound--or a dog, scratching on a window. He stood up, excited for the moment. "_Claws on glass!_" His sharp cry died into silence. They all considered it. "A snake ain't got pedicular exuberances," objected Potts. "Pedal protuberances, eh, Tip?" chuckled Mr. Hope, "What do you say, Grover?" As Roger looked toward his cousin he saw what surprised him most of all that had so far happened. Never in his stay at home or laboratory, intimately close to the scientifically brilliant, but poised, cousin, had Roger seen him lose his calm. Now, Grover stood up, and in his eyes was the same sort of light of satisfaction and triumph that a boy would show when he had successfully smuggled in and hidden mother's birthday present. "Roger is absolutely right!" "Claws on glass? A big dog?" asked Mr. Zendt. "Remember the cellar step clue." "A lizard?" Mr. Ellison suggested. "Remember Tip's statement about how he was knocked senseless." "Oh--a man with a--a what?" Mr. Millman was not so confident of his deductive ability. He paused. "I will leave you to work it out," Grover beckoned to Roger; "I must run out to the zoo." He was as eager and elated as a boy with a new football. He beckoned to Roger who followed as his cousin got his hat. "I want you to go to all the newspaper offices. Take a taxi. Get back issues for the past two weeks, maybe you'd better get them for three weeks back." "You know?----" "I have two theories. I want to make sure which is right." "Do you really think I got the right meaning out of the hisses?" "Precisely the correct meaning." "But it doesn't tell _me_ anything, cousin Grover." "Use my formula. Dig past appearances that can be falsified, to the truth. Marshal your facts, test each one, eliminate the impossible and what you have left is the truth." Telephoning to summon a taxi for Roger, the laboratory head was busy for a moment. Roger tried to employ the method just named. Youth, inexperience in doing such consecutive and eliminative thinking, he knew, hampered him. With a mind trained, through solving chemical, electrical and other industrial experimental difficulties, Grover's clever mind had skipped many of the links that Roger, slowly, had to take up and examine. He was in the taxi, with bundles of back issues of the city papers, on his way back, and still his mind was a maze of unfitted details. In the office, combing the papers for notes about snakes, or any other escaped reptile--he had to keep in mind that trail on the edge of the steps alone!--he got nowhere. No news showed up about lost, stolen or escaped animals or any form of brute or reptile. Grover, he saw, had returned, and was not joyful. "One theory went to smash," he said, "I verified your sound--claws on glass was the right deduction. But--that doesn't bring what I want." "What do you want?" asked Roger, eagerly. "To capture the culprit." "Won't the police?----" "We have no justification for calling them in. Nothing has been stolen. Nothing has been harmed." "The rats----the menace to the public!" "Roger, you haven't _studied_ those films Potts took." Roger got them at once, projected, one at a time, examining the screen images carefully. The cellar views, only proving that some object left no other trace of progress than scraped dust on step-edges, he considered and discarded. Those taken by windows, doors, intakes and outlets of the air-conditioning, and gas-exhausting roof, cellar and wall orifices gave no revealing clues. When he got to the wide-angles of the lower floor and stairway, and found no reward for his long scrutiny, Roger was baffled. Only the micrometric enlarged snaps and one time-exposure near the X-ray devices remained. He considered them ruefully. They gave no foreground evidence to help him. Roger, with defeat creeping over his feelings, was about to give up. He was fair, he told himself, when it came to interpreting sounds, but at the more important quality of being able to connect the clue with everything else, he was "stumped." What could those enlarged views hide from him? The walls, with racks of test-tubes, some containing chemical solutions, others holding cultures of various forms of growth that Mr. Zendt had accumulated or was studying, told him---- He stared, bent closer, climbed up on a chair close to the screen! After two minutes of close scrutiny, he jumped to the floor, and raced to find Grover. "Just by chance, in taking the micro-lens pictures," he gasped out, "Tip got in some of the test-tubes. Is that what you saw?" Grover, smiling, agreed. "What did it tell you?" "I arranged those racks yesterday. I have got a good memory." "I knew both those facts," Grover admitted, "and I, too, helped in revising our arrangement of the racks. Go on!" "The tubes that held the culture of the spinal disease germs--so dangerous that they had been delivered, personally, by the medical center bacteriologist, had _blue_ labels!" "You are 'warm' as the hide-and-seek game puts it." "I saw Doctor Ryder take them up, in his surgeon's clothes to prevent infection." "So did I." Grover acknowledged the fact. "He actually took two tubes that must have had the right labels because he would have seen what they were marked." "Labels can be soaked off and transposed from one tube to another, Roger." "I think that happened. He took them, went up, and we both saw him use the hypodermic needle." "But--" Roger could hardly restrain his thrill at having made as clever a discovery as the coming one: "Those two tubes--full!--are in back of others, right now. Not the two empty ones he incinerated to be sure the germs were all destroyed." "They are? How did you discover it?" Roger told him: "Our chemical labels that are a green, photograph a darkish gray; and our culture labels, that are a buff, photograph lighter, but still grayer than white paper. The poisons are labeled red and come out in a picture almost black. "_But blue except very dark shades, will photograph nearly white!_ And those two labels, hidden in a dark corner, show up in the picture where they might not be noticed in the rack." "Can you go further and say why no culture was allowed to be given, although the inoculator evidently thought his serum was genuine?" "Whoever was going to take the rats, did not want them to be dangerous to him." "Very nicely argued out, Roger," his cousin complimented him. "Now, we must find a way to draw that criminal who trains animals to do his work, into the open where police can get him." Chapter 4 AN ELECTRICAL TRAP Startling though Grover's statement that a man trained animals to be criminals was, it gave Roger the one link to build what he knew into a chain. Trained animals! That fitted in with claws on glass and made the rest of the puzzle fall into place. To Roger, it seemed clear that a clever animal trainer could teach his beasts to obey criminally intended orders just as well as make them do the ordinary tricks. What animal, he mused, would fit the conditions? A monkey came to mind as the logical sort. First of all, it was the one animal able to climb down a rope from the skylight on the roof, which it could have reached by being taken up the fire-escape on a candy factory next door, one story higher than Grover's research laboratory. Coming down in that fashion, it could have been made to do a trick taught for the purpose--take the white rats, put them in a sack, and fix it to the rope--or the sack could already be at the end of the rope. Then, unaware that it had set off an alarm, it could have wandered about, doing such tricks as getting into the light beams, pulling the switch to "on" for the X-ray and the other electrical devices. Such an ape, too, with its master joining it during the time it wandered about, could have invaded Tip's room, striking him with a huge paw, because it would be an ape; no smaller monkey could have reached down into the rats' cage. "How will you trap him?" Roger asked. When his cousin outlined his plan, Roger was animated. "It might work," he exclaimed, "He will turn out to be the one who brought the white rats. They were trained, too, maybe." "I wondered that you did not see why I bought back issues of the newspapers," Grover told him, "I had one idea that the thing might have been done by some zoo keeper; but the more possible notion was that some vaudeville act had trained animals. Now we do not need to comb through the advertisements of the theatre section. We know, by logical deduction, that we would find it." Roger, and Potts, carrying out instructions about which they said nothing to any member of the staff, assembled a mass of materials, apparatus and paraphernalia. There were microphones; and they employed the laboratory's device for producing infra-red rays, as well as a number of small cameras for taking motion pictures which Potts secured; to each one they applied a shutter-trip suggested by Grover, that would operate when a light-beam of the infra-red variety might be unknowingly broken by an intruder. Other parts, and wiring by the yard, they connected up. "But I don't understand it," Potts argued as they worked. "It's all right to say a monkey climbed in through the skylight way; but how does that fit the snake-trail up the stairway?" "I asked about that," Roger told him, "Cousin Grover was more in a joking humor than I ever saw him, and he said I'd done so well, he would leave that for me to work out, too." "Did you?" "I think so, Tip. How's this? Monkey comes in. No alarm on the skylight, because the magnetic plate under it would be 'on' all night and would have caught anybody--anything but a monkey able to jump at a command while it swung clear--or the man above swung it." "So far, so good." Potts waited expectantly. "The ape wandered around, until it heard a call it recognized from outside, on the street. It was trained to open bolts, and the only other bolt that wouldn't have a camera equipment and electric plate was our coal chute, that had the Chief stumped how to fix it." "And why would he have to go down there?" "To let in his mate--another beast." "And what was it?" "Well, what could leave a snake trail?" "A boa-constrictor, or one of them bushmasters out of Australia?" "What else--out of Australia?" Potiphar stared, thinking hard. "I don't know." "Something that hops, and balances with its tail." "A--you mean a--kangaroo?" Roger chuckled, nodding. "But why did they go to all that trouble, when a man could of swarmed down a rope, and got the rats?" "If he'd got caught--not knowing everything about the inside of our lab, maybe," Roger responded, "He'd go to jail. But if we got a kangaroo, or an ape, the animal trainer could know it and have an ad. in next day's papers, get back his animal that couldn't tell what it was there for, and----" "Well, what _was_ it here for? What made all that compulsatory?" "The motive made it compulsory, Tip." "You didn't tell me about any motive. Or how all this wire and stuff will catch anything when we don't know anything will come tonight, like you hint at." "The motive, Cousin Grover thinks, is to get into our safe, for our data and formula for synthetic camphor." "Well, come to think--one nation practically controls the camphor gum output, and if they want to raise the price----" "Or forbid export to any other country, in war----" "I can see how much it would be worth to have what we developed for one client. Maybe some foreign nation wants the secret." Tip was alert. His pale blue eyes and almost albino-white hair made him seem, usually, washed-out and not very bright. But with this thrilling possibility of intrigue and excitement brewing, he was as alert and intelligent as anyone could be. "We don't know. But Cousin Grover thinks he will draw them on, and he publishes in the evening papers quite a write-up about the completion of the data. A friend, a newspaper fellow, will help us get it into good space." "And so the Chief thinks this fellow with the ape and the mouses and the kangaroo is a criminal and made them criminals?" Roger nodded. They waited until the staff checked up with Grover all results from the day's experiments, and departed. Doctor Ryder, assured that his rats were not a menace, left with the rest. Then, carrying from the doors, windows, coal-chute, skylight and all other available openings, wires from microphones set there, Roger and Potts led them all to a three-stage amplifier, having a delicately diaphragmed headset in circuit. With that headset on, if a heart beat within a foot of any mike, a drum-beat could be heard in the headset. Light-beams criss-crossed the entrances so that they must be interrupted by anybody or any thing that came along. Each was in circuit with one lamp of a number in a shadow-box, and the one that would stop glowing would show which beam had been broken. Thus prepared to be warned well in advance of any intrusion, Roger sat wearing the headset as he monitored the volume controls. Police hid inside and outside of the laboratory. The safe, bathed in invisible rays, was provided with a new form of "capacity" protection so that anybody or anything touching the metal and standing with feet on the floor, would form a circuit and overload a sensitive and delicately balanced radio tube, that would operate a relay, putting into the circuit a criss-crossed series of small water-hoses, two playing along each side of a square around the safe, not easily observed when inactive. And in that water would be an electric current strong enough to paralyze and chain, without permanently harming the invader! He could not avoid it, because the water must fall and no one, even aware what would happen, could dodge or avoid the spray and the stream. The precious, priceless synthetic camphor secret was protected. As he sat, knowing that in the dark around him were Doctor Ryder, Potts, and his cousin, Roger felt a little thrill of expectancy and uneasiness. Had he foreseen the outcome of the ruse, it is a question whether he would have danced for joy or shuddered in terror. The trap caught something unexpected. Chapter 5 WHAT ELECTRICITY COULD NOT CATCH To Roger, the presence of Doctor Ryder showed that Grover suspected him. Of the whole staff only he had been told, included in this vigil. The headset was shifted slightly away from his ears; Roger listened, as midnight approached, to his cousin's chat with the experimenting medical man. "Of course I know that I am under suspicion," Dr. Ryder said. "The culture was hidden in my section. Other things look bad----" "Of the whole staff you are the only man I need _not_ suspect," Grover saw deeper into things than had Roger. "It is an old trick, to turn suspicion toward an innocent man by 'planting' something." That, Roger decided, was sounder sense than he had used. He had forgotten to dig past appearances to the heart of truth! "What do you expect will happen here?" asked the doctor. "The miscreant will come, with his menagerie, for the priceless camphor secret." "Pretty smart stuff," broke in Potts, "coagulating camphor with kangaroos." Coagulating was the wrong word, Roger knew; and the others saw through the meaning. "Claws on glass implied something tall enough to reach up that high on top of the cage," Grover explained. "The 'snake' trail and an animal with a dragging tail 'coagulated.'" "But why did the man take the white rats?" Potts was beaming, in the faint glow from the bulbs in the shadow box; tickled that his word had been so good; not dreaming that Grover was inwardly amused. "With the same motive that makes a magician do meaningless movements with his left hand while he really palms cards in his other hand," Dr. Ryder explained, "to make you look away from the real motive." "And he brought the kangaroo and the ape to confusicate us," Potts was being clever, he felt. "I'd say the ape came so he could be used to climb down a rope, and go and open the cellar trap that had no beam-alarm," Roger spoke up. "I looked up notices in the theatre columns and there is an act that has a boxing kangaroo, and the critic called it 'she.' In the act, she 'brings down the house' when a fire is supposed to trap the trained rats on the roof of a little house, and 'she' makes everybody laugh by taking the rats and putting them in the pouch they have to carry their young in." "Oh, yes, that coagulates," Potts agreed. Although all the others realized that the word meant to clot or curdle, and wanted to smile when it was used to mean "connects up," Potts, had they known it, was precisely correct--for they were to find that many deductions certainly coagulated, in a broad way of speaking, the real truth, instead of solving the mystery. If clotting and curdling means to thicken and make lumpy, then as Potts said, Roger's explanation did exactly that to their deductive cleverness. Roger, as the slow minutes dragged along, picked up with his headset whispers of the policemen outside a window, exchanging ideas about their tedious watch; and even the slip and rattle of shifting coal in the cellar bin. No invading menagerie, though, brought news to his intent ears. A tiny, but sharp click broke a long silence. The oil-burner relays of heating plants in adjoining buildings made such "static" on his home radio, he knew, but the heat would not be used in the hour after midnight. None of the apparatus or light was on the laboratory. The interpretation Roger gave was that in moving he had jarred some poor connection that made loose contact in his circuits; and he began testing his wires at soldered points, seating tubes, and shaking headset binding posts. He did not succeed in locating the source of the single sound, because things began to happen. From the darkness, and apparently from the upper floor, in a hollow, grave-yard sort of tone, an unexpected voice spoke. Roger, with power full-on, got a roar, and dashed aside the set to save his ear-drums, for a microphone had caught and had brought him what the others heard naturally. The voice spoke in English, low, deep, mournful and yet, somehow, menacing, as it said: "_Hear me. I am the Voice of Doom!_" Roger felt his blood "coagulate" in very truth. Grover, never more calm, although the unforeseen and uncanny call galvanized and terrified Potts and made the Doctor's face look absolutely horrified, leaped up, and vanished out of the small pool of dull light from the shadow-boxed panel. With the ease of familiarity, he got past their great transformers, and the storage batteries from which direct current was drawn for certain types of experimentation. He avoided, in the gloom, the new high-intensity-spark mechanism, and took the stairs two at a bound. Roger, impulsively starting to follow, remembered his duty, and in spite of his shuddering nerves and the cold fear always coming from any uncanny and unexplained happening, he stuck to his post. Doctor Ryder, attempting to follow, ran into the recording equipment and stopped, hesitating, as Grover, from above, threw on the lights. Roger got the switch-snap, but it differed from his other "click." "Nothing here," Grover called down. "Strange!" "Potts," Doctor Ryder turned his head, half accusingly, "are you a ventriloquist?" "A----" "Ventriloquist! Able to throw your voice so that it sounds as if it came from somewhere else than where you are." "Are you?" asked Roger suddenly. The other laughed. Grover, leaving the lights going, came down, switching on illumination all over the building; while several policemen came from concealment, blinking and staring around uncertainly, the experimenter in the bright light walked over and sat beside Roger. "Watch me closely," he half-smiled, but kept his eyes glancing around half fearfully. "I did not dream--it would happen--again--and here!" He spoke as if to himself. "No, that is not ventriloquism," he muttered. "It is some art of the Far East, known to the Lamas of Tibet----" Again, and in the same hoarse, menacing, hollow way, the sound was repeated: "Hear me! I am the Voice of Doom." Potts was shaking with fright. Uncanny and weird, the sound woke in the rather poorly educated man all the primitive fears and superstitions of his ancestors. Grover, listening with his head on one side, his eyes on the Doctor, spoke: "He isn't a ventriloquist, Roger. The changes in muscular and other throat parts developed by constant ventriloquial practice, do not show. We took a film, remember, of just such throat development in connection with our research for the clue to our case when the deaf man 'heard things.'" Roger, recalling that in that case a tiny click had also come, when he had listened on a headset, jumped to the conclusion that he had before found correct. "Somebody is using Mr. Ellison's little radio test-sender," he declared, confidently. Grover nodded. "Possibly. Go and see." "His private locker needs a key that is in the safe." "Never mind, then. I think you have the explanation, Roger." Grover sat down again, relieved, as was Potts. Dr. Ryder, though, seemed unconvinced. "Sorry, but I must dispute your deduction," he asserted. "I have heard that voice before, and it is sent by some Asiatic, wise in use of the hidden forces of Nature. It is a manifestation that is directly intended for me." Roger stared at him. "'Manifestation'? You mean--like thought transference or the 'ghosts' that spirit-mediums pretend to call on?" "Only this is more sinister and terrible, because it is the way that the Far East makes known to some intended victim the fact that he is to be punished." He rose, and began to pace. Roger, suddenly intent, caught at a passing "hunch." "Appearances" could be falsified. It appeared to be fact that something uncanny was happening. Might it not be the same sort of misleading use of one hand to distract attention while the other did some trick, as with the white rats that "appeared" to have been inoculated, were apparently "stolen" and so on? Quickly the headset was put on. He cut the output strength to avoid having his ears blasted if the microphone upstairs picked up that booming, hollow voice again. Grover, intently considering the Doctor's last words, spoke: "What do you mean by saying that you are being warned by some occult means that you are marked to be a victim?" The man addressed held up a hand. "It will tell you!" His face was set; he was listening. Again Roger heard the inexplicable sound. This time, no voice! Beginning in a low moan, faint and very much like the whine of a puppy that is hungry, it grew in volume, and its tone changed from a high falsetto, running down the scale and then up again, in cycles, constantly growing louder, while Grover, again rushing to the upper floor, stood looking around as, with a great grinding and rumble, following the last piercing roar of the sound, there fell silence. Doctor Ryder, rising, walked around the recording machinery and Mr. Ellison's newest camera, that worked with a stroboscopic lamp and ran its film so fast that no shutter was needed, as daylight did not act on it long enough in any spot to fog it. "That," he called upward, "was the real Voice of Doom." Grover, bidding Roger turn over the monitoring work to Potts, summoned his younger cousin. "Roger," as the hurrying figure came into the room with the vacant glass experiment-cage, "are you afraid to stay up here?" "Not much--but if I am, I will stay, just the same." "Then set up that sound camera, with film, so you can take in every foot of this partitioned room. Be ready, and if the voice comes again, switch on, for continuous takes." "You think--anybody is hiding?" "No. But a voice means something vibrating. I could not locate anything. The camera might do so." He went down, to give Potts some instructions and took over the monitor's post while the handy man executed his order, which was to mix fresh developers and fixing baths, and to be ready for whatever Roger caught. Doctor Ryder, helpful and desiring, as he made plain, to take away Roger's sense of fear by explaining how the Far East made so uncanny a manifestation by mental powers, handed him the can of non-flam negative so that Roger lost no time in "threading up" and getting all ready for his duty. Alert and steady, in spite of his chill of nervous uncertainty as to what might come next, Roger heard, seemingly from a corner of the small room, a thump. "Start it!" gasped the man beside him. But when two minutes of time had run out the film in his magazine and nothing more had come, Roger disappointedly took the film into the dark room and changed the magazines, hurrying back. Half an hour later, with nothing to break the tedium, the next amazing development came. Potts, in the dark-room, shouted, and tore out into the light, waving a damp strip of film. He had developed the film on the chance that the thump had caused some change. Instead, developing that film, he had brought, to wave before Roger's startled eyes, an impossible thing. On that film, in a different position on each Frame, or individual picture, a spectral monkey and an equally indistinct kangaroo hopped, bounced, and skipped, finally vanishing into thin air! Chapter 6 A WEIRD STORY When that uncanny film was projected before him Grover seemed unwilling to believe the testimony of his eyes. "It simply could not be," he declared. "That film was taken from a brand new shipment, wasn't it?" "Yes," Roger asserted. "And there were no animals in the laboratory." "Not animals we could see," said Doctor Ryder meaningly. Grover, rather sharply, demanded his exact reason for saying that. "I have heard the voices that seem to come out of nowhere," the experimenter explained. "I have traveled in the Oriental countries. I have heard strange things; and I have _seen_ things even more odd. In India, in China, and all the more in Tibet, there is what they call the sect of the Bon--Black Magicians." "Nonsense!" exclaimed Grover. "To a scientific mind--yes. To an ignorant native of a country without educational facilities or communication such as our radio, telephone and so on--not so nonsensical. Besides, I have heard and I have seen curious things." "Like what?" Tip demanded. "In India, a seed planted and an orange bush growing before my eyes. Or a rope flung into the air, staying aloft as if hooked to some invisible support, while a boy clambers up and seems to vanish. "In Tibet, as well as in India, men who can apparently walk on water. Of course, our science explains it as hypnotism--the man who performs the feats is able to secure control over some part of the onlooker's mind, impress _his_ thoughts on the other mind, and make one believe the trick is a real occurrence." "I have read about men who can walk on pits of live coals," Roger added. "Those tricks or those marvels do not explain this film," Grover was not satisfied, Roger knew by his tone. "How about telepathy? Thought transference?" "I believe," Grover answered, "there is some ground for accepting that as possible. It might be reasonable to admit that if a man, by years of practice, can train himself and also treat his feet so that he can walk on fiery coals, a man might become able to impress a powerful idea on another without words. But--on a film!" "In the sect of the Bon, or manipulators of the darker forces of Nature and of man's superstition which is half of black magic," the experimenter declared, "strange powers exist. I have read of a French scientist who has succeeded in developing a film so sensitive that a powerful thought, held by his trained mind, seemed to cause some changes in the film. This is a similar situation produced by some Oriental master mind, probably." "Or it could be that things like ghosts are true," Potts volunteered. "What do we know about the unseen things? Even science is finding things like bacterions----" "Bacteria," Grover corrected, smiling. "--In the air and water and blood. Well--I went to a spirit-meeting once. The woman threw a fit and talked awful funny about my 'deceased aunt on the other side' and told me things--now, if we brought in one of them there test mediators----" "Test mediums," Roger knew the right word. "They pretend to be able to communicate with spirits of people, but has it been verified?" Potts was too eager to argue that. He stuck to his suggestion: "All right. If we call in a trance medium, she'd tell us them spooks is around us, right now." "Just because the appearance seems to be that," Grover stated, "is no basis for accepting the explanation of telepathy. In that case, Doctor, _we_ would have seen the objects, the animals. We did not. You and Roger are sure you saw nothing. There are only two possible ways the phenomenon could happen." "How?" Potts was anxious, eager. "First: the film had been exposed, previously. Second: some one hiding in the dark-room, while Potiphar was not closely observing the developing tank, changed for the original film in its rubber wrapping, this one." "I used a deep tray, full of pyro," Potts stated, "wound the negative around in the rubber, but didn't use a tank, on account of them bein' stained, and you was so positive about fresh stuff, I got a deep tray, never used before, and watched every step of developin'. The second way of it happening is 'out.'" "Then we will test the possibility of the first," Grover beckoned to Roger. "Telephone downstairs for a taxi, and meanwhile, plug in the telephone in the screening room for me." When Roger had summoned a night-hawk car, his cousin reported his own activity. "I got the night-watchman at the Bizarre Theatre, where the animal act finishes its engagement tonight," he said. "The white rats and dogs, and several monkeys are quartered at a pet shop near the theatre. There is a kangaroo, and it stays in a stable. Here is the address, Roger. I want you to talk to the keeper, or some stable attendant who can say when the animal was taken out and when returned." Roger, when the taxi arrived, sped to his task. He found a sleepy attendant, surprised at the time, so near dawn, for a visit from a young fellow who wanted details about the kangaroo. "She ain't been out this night," the youth assured Roger. "How about last night? Or the night before?" "Neither time." "Oh, but she must have been." "Well, she wasn't." "Well, then, was the ape?" "What ape?" "Doesn't the man who has the trained animals use an ape?" "Never saw nor heard of no ape." Roger was puzzled. "Well--" He recalled a flash of inspiration that had been all his own. He pulled from his pocket the tiny, compact camera, small magnesium-flash gun, and tripod folding like a pocket ruler, very slender, but sturdy when unfurled. "Can I snap her picture? Our laboratory wants it to study." "Cost you--how much you want to pay?" "A quarter." "Go to it, buddy." Roger, with the hand of the youth clutching the coin, got a good snap just as the flash startled and almost stampeded the kangaroo and several horses and a few mules quartered there. He returned by taxi as the East streaked rosily to the rising of the sun. "There was the kangaroo, but she had not been out--at least, the attendant vowed she hadn't," he said. "But I've got her picture to compare with the ghost-one." "Clever head," commended his older cousin. He went away, pleased, to develop, print and fix his prize. While negative and contact print were being fixed and washed, he sat at the table in the adjoining room where the mysterious voice and roaring cry had been located, thinking hard. "I wonder," he mused, "if it _could_ be that the film I used had some sort of emulsion that would be sensitive to rays we don't see. You can take a picture through a quartz lens in a room that seems to be pitchy black. I've done it, with our special equipment. Maybe a film coating that has some light-sensitive ingredient sensitive to high-frequency vibrations of light, could catch what we don't see, and--who can dispute this?--there may be in the air, all around us, forms of things that we can't see." Science, he reflected, had managed to develop instruments so delicately adjusted that they caught earth tremors and recorded them, when the disturbance might be hundreds, thousands of miles away from the seismograph. Their own Mr. Ellison, the cleverest and best informed man in the city, on electrical matters, was preparing a camera that ran its film at high speed past an aperture: a light more actinic than sunshine alternately lit and was out, but so rapidly that its flashes impressed pictures lit by it on the film, as many as a half million or more a minute, he believed. The papers had written it up as that many. And scientific instruments pictured, in graphs, of course, such invisible things as electrical waves; yes, and radio made audible the inaudible electrical frequencies sent by an aerial, caught by another, transformed into sounds by other invisible agencies. Grover, when appealed to, nodded. "Anyone who has operated a modern laboratory knows better than to make fun of any theory," he admitted. "What our Pilgrim ancestors would have called a witch talking to Satan, we see as an old crone listening to her radio." "They had their witches-on-broomsticks," Roger chuckled. "We see airplanes. That's so." "It doesn't pay to scoff at your theory. It may be a scientific possibility to prove it correct, some day. But, just yet, let's not take it as the only explanation of our ghosts. I realize that the film can was one of our last shipment, that you had to break the label, proving it had not been tampered with, apparently. Still, some test made at the film plant could have been inadvertently packed. We got it." "My snap of the kangaroo will prove or disprove that." Roger went to get the force-dried bromide enlargement and the camera film taken in the haunted room. Comparison showed, apparently, the same animal, in one case sharply defined, a solid object; and in the other, just a shadowy specter. They looked to have the same proportions, though. "My theory is that someone hired the animal trainer to send his rats here, so they could be removed. He could have read notes of the Doctor's planned experiment in a science column of the papers." "Then where did the ape come from? The attendant was sure the act did not have any ape in it." Roger was still unconvinced. "That may have been the trainer, an agile man, in a masquerade costume of Tarzan-type." "It might." "I will admit that Doctor Ryder tells a story that makes wilder theories possible," Grover added. "The policemen are gone, now. He gave me an outline that made me discard the theory about danger to our camphor substitute. Suppose you listen with me to the full recital." The narrative the man spun was amazing. "Shortly after I left college," Doctor Ryder began, "I became interested in study of medicinal herbs, because an old Indian in up-state New York, who had earned a reputation as an occult doctor, had made some astonishing cures of seemingly incurable cases. A friend and I got into an argument. I supported the Indian's claims; and my chum argued it was impossible, that it was pure medication and not at all due to magical powers as the people claimed. "I went to the Indian to study," he went on. "He took a liking to me, and after a long time, teaching me secrets of wayside weeds and the properties of common plants in medication, he confided that in the Far East there were schools in which full knowledge of herbal medication could be learned by those qualified to share the secret--a dangerous one, because knowledge of it might enable some evil-doer to procure enough deadly poison among common wayside flowers and herbs to destroy a city's populace." Skipping his explanations of how he finally secured the Indian's help in reaching some one who knew more, and of how he finally found himself an accepted student journeying toward a Lamasery in far-away Tibet, Roger's next intense interest came with the declaration: "I learned something about what Ponce de Leon spent his time seeking, the secret of eternal youth. I learned much about marvelous properties of common plants--and then, through a desire to view with my own eyes the greatly revered Eye of Om--a precious jewel set in the forehead of a sacred statue of Buddha--I became a hunted man, suspected of a theft I never dreamed of committing, then. The Eye disappeared. I was suspected. My perils were many. I finally escaped from the land. But twice, since I began my private researches, I have been reached by that strange warning, the Voice of Doom--just as you, who have been my friends, heard it tonight." He bent forward in his chair, earnest, eager. "I know who took the Eye of Om. If only you would help me to restore it--if only you _could_." Chapter 7 SCIENCE TO THE RESCUE When he heard Doctor Ryder's startling plea, Roger's clear, gray eyes lighted with a fire of hope and excitement. To be involved in a mystery in the laboratory was thrilling; but to have a share in restoring the Eye of Om, evidently a priceless gem, would be more so. His quick mind flashed over the fascinating prospect; but with equal quickness he saw the reason why Grover sat so silent and unimpressed. A man accused, anxious to return a jewel, would merit help. A man who knew the real taker of the gem and wanted it restored meant possible trouble. He might want them to help him get the gem away from its possessor. That was not their duty. It was police work. "Please be more definite," Grover said. "I don't want you to help me 'steal' the gem from anybody," the medical experimenter declared. "I need financial help to buy it." "To buy it," Roger exclaimed. "That would take a lot of money. Would the people in Tibet pay you?" "They would pay a handsome profit, Roger. But it would not cost such a vast sum as you may think. You see, the one who has it is not aware of its value." "That is curious," remarked Grover. "What happened was this: I went to the temple with a native priest to see the marvel I had heard of. While we were entering, a figure slipped away out of another door to the sacred crypt. As we approached the great figure of Buddha, I saw a vacant hole in it and realized that the priceless jewel was gone. Terrified at the thought of being caught, suspected or in some way associated with the crime against their holiest treasure and venerated religious symbol, the priest and I hurried away just as other temple attendants discovered the situation." Without being certain, the rest of the gem's history was assumed to be that the thief, terrified, had thrown away his loot. One of his camp staff, an ignorant, though strong pack-carrying youth from an American city, whose way the doctor had paid for his ability to obey orders without trying to improve on them, had found the gem, in a fissure of the great mountain pass they traversed in escaping. He had evidently taken it to be only a beautiful native art object and had put it in his pack, apparently, without mentioning it, meaning to bring it back to America to "give to his sweetheart," as the medical experimenter supposed. "At any rate," Doctor Ryder summed up, "he is living here in the city, his sweetheart had forgotten him, he has that treasure, put away, and I dare not go and talk to him about it. I know he has it because he has shown it, as a souvenir, to people who have recognized its worth without knowing just what it is. He would probably sell it for a fairly good sum, if approached by someone from a museum; but if he was told its history, and knew its real value, he might sell it to some gem dealer who would put it beyond my reach in some private collection. And my life would be forfeit, because I cannot prove, in the circumstances, my innocence to the Tibetan Dalai Lama and his vindictive, fanatical subordinates." Grover, as Roger watched him eagerly, anxiously, considered the situation thoughtfully. "I suppose that there are complications," he said, finally. "Some international jewel thieves must know the affair." "Exactly." The other man nodded. "That accounts for the entry, here, night before last. From the use of a kangaroo I would assume that an Australian is interested----" "An ape would mean somebody from Africa," Roger argued. "While the strange projection of the Voice of Doom implies that the Tibetans are preparing to strike at me," Doctor Ryder added. Grover sat considering the matter. "With that all granted," he said, finally, "it is easy to see what caused the queer ghost-figures in our film. I assume that the purpose of using the trained boxing kangaroo with a pouch to carry its young, also trained to 'rescue' from fire, was to furnish a novel way of hiding and removing the gem which evidently the thieves think, as do the Tibetans, that you have." "Certainly. In your safe." "And whoever came," Roger was able to fill it all in, now, "with the kangaroo, meant to get into the safe, get the gem, put it in the animal's pouch, and then, to make it go away safely, he had to turn on the fire alarm that rang a bell, the way it must ring in the act, for the kangaroo's signal to rescue the rats. It rescued them, and hopped away, to its attendant, just the way it would in the theatre." "And what about the film?" asked Doctor Ryder. "Some was probably in the 'sound camera' by the cage. Either in trying to shut it off or in an accidental knock against it by the animal, the 'continuous' lever was thrown. Focused with a diaphragm opening to catch the white rats' movements under a vivid light, the lens got only an under-exposure in the light from the ceiling!" "Logically," Grover finished up for his younger cousin, "the man knew the camera had been running. He took out that magazine, took the blank film from the new can to replace it, making as many snaps as had been made of the rats, jarred the continuous-take lever on by accident, giving us the clue of claws-on-glass as his animal came to the cage, with the ringing of the alarm bell." "Science to the rescue!" Roger exclaimed. "Now we know it must be the animal trainer who is the key-man. If he did it for his own greed, we can protect ourselves from him in the future." "If he was a hired accomplice of others, as I assume to be most likely," Grover added, "he can be compelled to tell us the facts." Declaring that he would interview the man in person, bidding Roger to add to the few hours of sleep secured before their midnight watch, the laboratory head, as the staff began to arrive, urged Doctor Ryder to say little, and to wait until consideration could be given to his plea that they help him get the Eye of Om. On the emergency couch, in a small combination of rest-and-first-aid room, Roger stretched out without feeling the least bit drowsy. The excitement was still keeping him alert. "Science to the rescue," he mused. "Modern apparatus is wonderful and understanding how it works and what can be done with it ought to help people solve many mysteries. They have developed instruments to measure nerve responses and other things. There is the lie-detector for one device to help fight crime. "And if scientific appliances, and scientific understanding, both can be coupled with Cousin Grover's axiom about ignoring appearances and digging to the heart of truth, analyzing down to the basic element of a complex combination, it will be even better." He thought back along the course of the many happenings, and of all the clues that scientific apparatus and wisdom had opened up. He sat up suddenly. "Science to the rescue!" he repeated to himself. "We don't need to wait to see if the animal trainer will tell the truth. We can find out right away." In the files he found the enlargements made the day before, from the "routine" wide-angle and close-up views Potts had taken. The folder full of pictures, and the rolls of film from the cabinet he studied carefully. Roger's study was concentrated on the close-up and magnified detail of door locks, window catches and all openings. If any catch had been moved the picture should show to the screen-observing youth, some abrasion, or some disturbance of rust, or at least a displacement of the accumulated dust. Nothing. Nothing in any picture, on any film! "That tells me that the entry was made through the skylight, as we had thought," he decided, but added: "Or--does it tell more?" An ape, he felt sure, could not have been trained, or have sense, to swing so as not to touch a magnetized and super-charged metal plate concealed by being painted the same color as the wooden floor under the skylight. A man, dressed as an ape, might. But it seemed like a long way to go around to get through, when a more simple possibility was open. Roger assumed that it might be possible that one of the people interested in securing that priceless treasure which could be supposed to be in their safe, could work there! The fact that no pressure from outside had given its clue in the pictures, showed him that some "insider" might have opened the only possible place to get the kangaroo in--the coal chute. His examination, with a high-powered, beam-focusing light and a magnifying lens, revealed that rust under the bolt had been scraped. But the pictures had shown no sign of the use of "jimmy" or other implement for prying back bolts! An "insider" was responsible for opening that chute trap. It would be simple to associate kangaroos with Australians, apes with Africa, possibly India. It would be just as easy to narrow it down to whether any of the staff connected-in with either place. A man from Australia would naturally think of a kangaroo and its peculiar qualities and usefulness for his plan. A man familiar with a country wherein apes were found might see the usefulness of that animal, or would resort to a costume for disguise that a man from the coal counties of Pennsylvania, for instance, would not have thought of. To the office files Roger hurried. All the data concerning each employe, such as age, experience and so on, was there. When he had looked, Roger put away the sheets of data carefully, and waited eagerly for Grover to return from interviewing the trainer. Two sheets had told him much. One had given its maker's experience on an expedition to India for a power-plant construction job. There was India, ape country. Roger knew that in many sections of India, apes were sacred. The other sheet had told him that its maker had worked in Australia under Government chemists, studying the inroads of a destructive insect. He had two names to give Grover. Science, with brains, _had_ come to the rescue. Chapter 8 BASKETBALL AND BRAINS "Admitting your cleverness," Grover, informed by Roger, was more than surprised, "I still find it hard to accept your deductions." "I don't deduce anything," Roger argued, "I only got the facts. I think I would almost as soon suspect you as to suspect Mr. Zendt, or Mr. Ellison. But----" "The appearances certainly look bad," Grover agreed. Zendt, quiet, calm, thorough, had been in Australia, his own record attested. Mr. Ellison, than whom no one was more clever in electrical matters, had built power plants for a big utility company, some of his work having been in Calcutta and Karachi, both Indian cities. "I will watch them unobtrusively," Grover stated, "while you do an errand for me." Roger waited for instructions. "I went to the address given by Doctor Ryder, just to check up and see if his fantastic story had any basis of fact," Grover told his cousin. "Sure enough, there was dull-witted Toby Smith, and when I represented myself as an attache of a museum--I am, you remember, one of the sub-committee on Egyptian Embalming research--the young fellow, about twenty-two, promptly enough produced and let me study the memento of his adventurous trip into Tibet. He certainly does not realize its value, and to me, inexperienced as I am, it appears to be a marvel of Nature's crystallizing stresses, as well as a credit to the Tibetan jeweler's craftsmanship." Roger was all ears. "To him it was a souvenir, with little other value--a bit of art-glass, he told me he supposed it was. "I bought it. You are to go and get it." "Why wouldn't he let you bring it?" "I thought of the possibility of being watched----" Oh, boy! was Roger's mental comment. "I satisfied myself that I had not been; however, I had arranged to have you take him, in return, a small moving-picture hand-camera that he had confided to be his heart's desire. In exchange, he will surrender to you a large envelope which will contain, disguised in heavy documentary-looking papers, the art-glass." Grover smiled amusedly. "And if you have any matches or duplicates in your stamp collection, you might get intimate enough to trade for some of his foreign over-stock of stamps." "I'll take a batch of duplicates," agreed Roger. His taxi, depositing him at the address given by Dr. Ryder, waited. The Smith chap, he found, was intensely interested in collecting, and had a fine collection of stamps; in fact, he spent most of his small earnings as a dishwasher, on philatelic prizes. He and Roger grew intimate and compared notes, exchanged stamps, and chatted about the Tibetan expedition Smith had joined as a young man, several years ago, he claimed. He told about a Devil Dance, a religious rite, he had seen, wherein all the devils and evil spirits were represented by disguised and horrible-looking men, who chased a wildly terrified human soul, as a boy represented himself to be in the pantomimic dance. Exhausted, unable to escape, at last, he was supposed to be destroyed. "It is supposed to show how we are chased by temptations and all," Toby Smith explained; and he told of the Tibetan huts and other nomadic possessions of the ever-moving grazers, and other interesting sights. Then he gave Roger the heavy, sealed packet--Roger felt the lump supposed to be the gem. Putting it in his coat with his stamp envelope, Roger took his leave a little regretfully. Smith had been an interesting person to talk with. However, he concluded, he would, as he had promised, help with the new and mystifying hobby of taking "movies." The taxi--he had forgotten about it--was gone. That did not much surprise Roger. The man had no doubt gone back to the laboratory or had gone on elsewhere. In the first case they would have told him they had a charge account with his company; in the other, knowing it, he would have picked up other fares and forgotten the young man he had brought there. Roger, rather closely confined indoors by his laboratory work of giving out hypo, sodium bisulphite, or, perhaps, electrical requisites, decided that the air would be beneficial. He walked. It came to him after a few squares that Cousin Grover had thought of being watched. Roger glanced around hastily. He wondered if that slouching fellow with the low-brimmed hat, could be following him. He whirled in his tracks, to retrace his way past the other, but the youth turned in at a cigar store, and Roger, with reassurance making him whistle gaily, walked on. Almost at the laboratory street he looked back again--and was puzzled. The youth was on the trail, possibly, once more. But he had not kept close; instead he was leaning against another smoking goods shop window-frame. Roger, thinking to himself that such espionage could do no harm, changed his course, and instead of going directly down to the laboratory street, he turned into the one behind the laboratory, so that if the youth had gone into the store to telephone his progress, he would prevent being met by anyone at the logical corner he had been heading for. He would approach from the far end of the block. To his dismay, this seemed to have been anticipated. There were about a dozen boisterous, rowdyish young men and boys racing to and fro in a rough, noisy game of tag. They might be innocent of any interest in him and his tight-buttoned coat; but he was taking no chances. He turned, retracing his way. To his dismay, one, being chased by the pack, came with long legs down the street. Roger stopped at a drug store intending to go in and telephone for Tip; but a woman with a baby carriage obstructed the entranceway. He changed his plan quickly. Dodging around her, he walked rapidly toward the candy factory adjoining the laboratory. The roughs were passing him. Suddenly they were all thronging around, pushing, not caring whether he got into the mixup of thrusting, hoarse-yelling gamesters or not. Roger felt a little bit dismayed. One of the tougher and taller youths caught hold of his tightly buttoned coat. "What you buttin' in our game fer, huh?" Roger spoke quietly. "I wasn't." The hold on his coat was too tight to break; they were behind him as well, and escape was impossible. "What you got in your coat--candy?" "Nothing much but a packet of lyddite--the explosive. Be careful!" His ruse was not successful. One caught his shoulder. "What's that, now lyddite?" The grip of the other held, and Roger felt the buttons rip out. As quick as a flash he had his hands on the packets: feeling told him which was which. He snatched one out, and with his eyes fixed over the heads of those he faced, he shouted: "Catch it, Tip. Here she comes!" and he made a move to back out when they would turn to see who he spoke to. But that ruse also failed and in sudden desperation Roger realized that he must keep them from noticing that his coat pocket still held something. His basket-ball skill, that had enabled him to make goals by the tosses that seemed impossible with antagonists all around him, he summoned to help in his crisis. He had noticed in the second floor office window, the work basket some woman had put aside, full of samples she had brought in from the wrapping machines. With a deft flexing of muscles and a quick eye-glance to make sure of distance, wind and other factors, as hands stretched to snatch his packet, Roger gave it the well-rehearsed basket-ward toss. He saw it, as baffled, disconcerted youths looked up, fly in a clean trajectory to lose momentum just above the basket. It seemed to hover in the air. It dropped into the basket. It stayed therein. As if trying to recover a loss caused by such quick thinking, the ringleader wheeled and raced into the building, evidently to ask for the envelope thrown up by a boy at play. Roger, as the rest hesitated, pushed through, and hurried for the lab. The others broke and fled. "Tip," Roger greeted the handy man as he entered, "I'm going to phone the people next door to hold an envelope full of stamps I threw into one of their baskets to save it from a gang of rowdies. Will you go and recover it, please? I have to deliver a more precious pack to my cousin." Tip brought back the stamps, quite safe. And, also quite safe, their strong-box held a scintillating, vivid, thousand-faceted emerald, flashing its sun-fires of refracted light; as it had done when in the forehead of the Buddha it had symbolized, the all-seeing, all-ways-looking Eye of Om! Chapter 9 THE VOICE IN THE SILENCE "Had your sleep out?" Grover shook his cousin. "It's almost eight and Aunt Ella has the bacon on." Roger rubbed his eyes, snapped awake. "Is it all right at the lab.?" "I knew it would be. We left Tip to take turns watching with the men from the Falcon Patrol Agency. Two at a time, one on each floor. But I never count on human watchmen alone. They can be careless," Grover talked as Roger dressed. "I know. Capacity-overloading plates all around, so that anybody or anything that got near any apparatus would overload an aerial field and upset a delicate tube and open a relay, stamping the time, and starting cameras with sound-films in them." "Exactly. Just talked to Potts. Nothing at all happened." Arriving at the laboratory, earlier than the staff, Roger and the Chief verified the static condition. "What do you think of this?" Grover took his cousin to the sound-recording mechanism, the type that uses a large phonograph record for the sound that synchronizes with a film in certain motion picture studios. He explained that as a double-check on any possible development, he had hooked up the recorder to a separate microphone system, all concealed flat-disk, super-sensitive diaphragm models, that were set in operation by any interruption of infra-red beams. "That's something!" commended Roger, examining the arrangements, "of course, with the reports in, I may as well put away the record to keep dust off it during the day." Grover agreed. Roger moved aside the recorder which had rested on the outer edge of the disk, just past the polished edge of the wax. "Here!" he cried out in surprise, "this isn't right. There is a sound-track cut!" "There can't be!" "Well, look, Grover." The older cousin stared at the abraded surface, the cuts in the surface of the composition. "But that is impossible," he stared, unbelievingly. "Let's give it a playback," urged Roger. He hurried to give the surface a good brushing with a soft brush, exchanged the diamond-pointed recorder for the type that hooked up with the electrical amplifiers and speaker in the screening room. He adjusted the mechanism to run a minute before lowering the pickup onto the disk, to give him and his cousin and Tip time to get into their tiny theatre. The low rasp of the needle as it ran over ungrooved parts was all they heard, for several breaths. Then: Out of the speakers, amazing, booming like the hollow groans that had followed the voices--as they now did!--came the ghostly salutation and warning: "Hear me! I am the Voice of Doom." Again, while they stared at each other with dilated eyes, the needle ran with no pickup. Then, again: "Hear me! I am the Voice of Doom." There rose that whining, shrieking moan of the demented and tortured puppy, lowering in pitch until it became a hoarse and strident howl, slowly falling away in volume but dropping in pitch until it sounded like the moan of wind through stretched silk, ending, as had ended the original, spooky manifestation upstairs, in a grinding, abrupt rumble and silence. Before the staff got there Roger had developed the sound-films of all the small cameras, but not one had been impressed with picture or audible sound record. It was uncanny and inexplicable. The Falcon men and Potts declared solemnly, and with sincerity, that they had seen nothing, had heard nothing. This supernatural appearance startled even Grover. Though he did not depart from his usual calm or drop his cold poise, he looked more than ever solemn, and even mistrusted human watchers and his electricity-and-water protective device so far as to search the safe. The jewel, as well as the camphor data and other precious things, to his, and Roger's, relief, were intact. Doctor Ryder, who was given a demonstration of the spectral recording, looked dismayed. "If I do not return that stone," he gasped, "my life is not worth insuring. This is the third warning, and conveyed in a way that makes me very certain that we are dealing with a sinister and very occult body of priests." "How do you propose to return the jewel?" Grover was practical. "I dare not let it be known that I have it," the medical experimenter declared. "I have thought of going to Tibet--but how shall I get into that temple, and how give back the gem? White people will be all the more forbidden access to the place; and I am already suspected of having taken the Eye." Grover considered it seriously. Roger, too, gave his best thought to the puzzling complications. "I don't suppose they'd have radios in temples in Tibet," Roger said, half-hopefully. "In the Dalai Lama's palace there is a radio, yes." "Short-wave?" "Probably of the best. We cannot resort to broadcasting, Roger," his cousin objected, "the international gem thieves might pick it up." "That's so----" "Besides, to ask them to come and take it, as I suppose you had in mind, would bring every gem hunter, in disguise or otherwise. And it might lead to worse consequences than theft. They are fairly desperate, cold blooded people," was the doctor's objection. Tip, listening, put in a suggestion. "Let one o' them that's been fetchin' kangaroos and apes take it. _Then_ radio who's in the possessive case. Let _them_ get the Voice of Doom after them." Grover smiled, shaking his head. "Tip and I could take it in an airplane," Roger hinted eagerly. "There is only one logical course open," Grover gave final decision, "hold everything static. Make no move. Safeguard Doctor Ryder, with the same type of protection we have given the safe, in a modified form. Then, when the promised Doom arrives, its emissaries can be informed that if they furnish proper credentials they may have their Eye of Om." Tip looked as disappointed as did Roger. No Tibet? No adventure? No thrills? "I suppose," Doctor Ryder shrugged, "it is the sure way, though not too safe for me, no matter what devices you arrange. If you knew the hidden forces of Nature that those Lamas can call into play, modern scientific protection would be as useful as a child's toys to combat unseen dangers that strike through the air." "I will pit my laboratory equipment against any force you can tell me about," Grover spoke confidently. "Well--as one example--how would you guard against mental suggestions sent by a powerful will, in my sleep, perhaps causing me to leap out of a window?" "I have heard of such powers," Grover admitted. "I have never seen them verified. However, for any occult science I am sure that we can find a material device to counteract at least the effect on your safety." Although Doctor Ryder was skeptical, he shrugged and submitted. "I will arrange your room so that nothing can get in, you cannot creep, crawl, run, jump, push or otherwise escape," smiled the scientist. "I shan't say what will be set up, and then there can not be any way for you to frustrate my plan to keep you safe." Potiphar, with Roger, heard some quiet instructions. The sketch and specifications they got made both of them chuckle. Any secret schemer, thief, priest of Tibet, or what, must "go some" to cheat the mass of light-beams, selenium cells, the recording phonograph, a camera, and electrified door and window seals that as long as current held them tight, could open only to Grover's own secret key, filed to touch only certain contacts in a tiny slot on the circuit-cable just outside the rooms of the doctor. Tired and full of content after saying good-night to their protege, Roger saw the switch set "on" and went home with Grover to sleep soundly. Nothing could enter or leave that sealed place! And to show the fallibility of human wisdom, Roger waked again in the hour before dawn to hear Grover answering a wild summons from a Falcon Patrol Agency guard at the Ryder home. "Better come," he was telephoning, "I can't rouse him or get him to answer; and from the observation port I can't even see him in that room!" Chapter 10 A DEFEAT FOR SCIENCE! Shudders of superstitious fear shook Roger's nerves as he flung on his clothes. Rooms that were locked and barred he had read about in detective stories; they had been entered. A room not only so sealed but, far better, sealed by locks that not even Potts or Roger could have unsealed, was as impenetrable as a solid block of metal. Yet some uncanny, mysterious thing, force or creature had penetrated! Unless, and he caught at the idea, unless Doctor Ryder had been worked-up and nervous, and had dreamed some nightmare that had made him hide. No matter what had happened, no matter what force had beaten the scientific measures employed, they would know the facts, because the registering devices could not have been stopped by the doctor himself, let alone any outside person or power. While that current flowed in the circuits, the devices must operate; and even if any wires were cut, still the automatic mechanical springs would run the recorder and the camera. Driving on speeding wheels, Roger and Grover got there in quick time. The Falcon man rushed up as they leaped out of the car. "Every fifteen minutes," he reported, "the way you said, I put my copper key in the slot on the plate over the observation port you had cut in his room door, so the plate would move aside as long as I needed to look to see him in bed. Last time he wasn't there. Up to then he'd looked to be sleeping sound." They hurried to the room door, on the second floor, down a hall. Swiftly, while Roger watched, helping as he could, Grover took an observation, let Roger see the empty bed and vacant room. The next move was to test, with ammeter and test-circuit, every electrical wire that had been necessarily exposed outside the room. Not a circuit was broken. Not a wire had been cut. "Very strange," even Grover was baffled, "the current is on, full strength, in each circuit. Try to get in." Roger, at a signal from the Falcon man, worked on the door locks with the keys that rightfully opened them; while the man, on a ladder outside a window, tried to pry open catches or shift the burglar stopper built into the casing. No success. "The man may be dying," the Falcon agent grumbled, "and we stay out here, testing." Roger, too, wondered at such callous but methodically exact procedure. Grover, paying no attention to their tell-tale faces, calmly inserted his key in the secret cable-slot, and cut out the circuits. At once Roger was able to turn his door key. They hurried in. As he looked around, at the crumpled bed sheets, at the hollow on the pillow, Roger knew that a man had slept there. How had he been spirited away? The closet was wide open, and although clothing had been flung down, although bureau and chifforobe drawers had been upset as if in a search for something, no signs of violence showed. "Get the record from the phonograph," Grover had made swift inspection, "and the camera film. They operated, of course. You can see the grooved track on the record. We cannot waste time looking for clues here. They will come from our spies, the film and record, at the studio." Rapidly they assembled the things needed and drove to the lab. With Tip, ready, eager, and quick to help, Roger got the film into the tank waiting on their arrival, and set the screening room turntable for the playback. In no time after their arrival they listened to the revealing details--and were again baffled. The record, after running along for a few seconds, suddenly spoke that weird warning, "The Voice of Doom!" As before, it was repeated and was followed by the uncanny and shrill screech that ran down the scale to a groan that died in a sudden sharp grinding stop. "Let it run!" begged Roger as Grover was about to stop the motor, "maybe he gave us a clue after that waked him up." There was a scraping of the recording needle running without vibration over the disk for a few seconds, and then they heard, very faintly recorded: "_You_--Clark!----" "Who's Clark, Cousin Gro----" "Sh-h-h!" The recording was again audible: "How did you get in? What do you want?" A few instants of silence. How could the answer fail to be recorded? Roger thought swiftly that a whisper should have left a faint report of its existence. "It isn't here.... Look, then.... What do _you_ know about any laboratory?... I don't know the combination to any safe!... Yes, let's go there. I will be very glad to go with you, Clark! The great Joseph Z. Clark----" Only Doctor Ryder's very easily identified voice gave the responses and although Roger cut in more output power and added a stage of transformer-coupled audio, the speakers gave no intermediate words. They were easily guessed at, of course. Potts, bringing the film, still sopping, groaned. "Not a thing on it. Wasn't even exposed." Grover and Roger looked. When light acts on a silver-bromide emulsion, it develops dark grains of silver where light has fallen, leaving the shadows unaffected within the degree that they lack light, thus giving the shadings that become a picture in the positive print. All over, and for its whole length, the film that had run fully three minutes showed as clear of developed silver as if it had not run through the machine as evidence proved that it had done. "A card over the lens," Grover grunted. "Of course! This Joseph Z. Clark is a clever man." "And so is Doctor Ryder, for he must have guessed that the recording was going ahead, and he told us all he could." "Yes, Roger. And they haven't been here yet." "So they will walk into a trap," finished Tip. They made hurried preparations, hiding the Falcon guards and finding concealment for themselves. Doctor Ryder had said he would "gladly" bring the man. How wise! He would know that they would get him, there. They did not have a long vigil. In the tell-tale shadow-box panel of lights wired for all entrances, the one to the cellar coal chute died out. Roger felt his nerves quiver, his muscles grow taut. All they had to do was to wait. When the pair got in, came up the stairs, walked over to the safe, the infra-red beam would break, tripping relays that set off small water-streams that would go all ways around the safe, charged with a current that could chain a marauder in his tracks. Doctor Ryder, knowing about it, would stay out of range, sending his captor, the miscreant they wanted, to his defeat. They crouched, Roger behind the recording device, Grover in the office, Tip near the stairs to the upper floor, the Falcon guards at three strategic points near ground-floor windows. There was the silence of a deserted building as they waited. Minutes passed. The intruding thief was careful, Roger decided. Still more time passed draggily. Roger began to grow cramped, and also very uneasy in his mind. What was going on? Was it so wise to wait? Why not throw on some light. Better sidle over and ask Grover? No. Better wait. He strained his ears. He heard only what seemed to be the drip of a faucet in the chemical washing-sinks. Tick! Tick-et-y--tick. Silence. Tick! Tic-tic--tick-y. A wait. Tick-tick. He tried to focus his hearing on any other possible sound. The drip-drip effect seemed to cease. He wondered about it, but decided that it had not been a faucet but had been a few drops of collected water running down the drain and striking in the trap. But as he wondered about it, he began to feel that it had been a metallic sound, not so much a soft drip. Risking censure, in his growing uneasiness, he leaped to his feet and threw into circuit his small pocket flash. Its beam stabbed the darkness, here, there. He shouted in dismay and horror. The safe door, caught in a flick of the beam, stood wide open! Tip threw a wall switch. No light came. Then, suddenly, the lights leaped on, water flowed from the hose. Too late! Science had been cheated of its guarded treasure! Chapter 11 A PUZZLING THUMP While Tip was rushed out to the street, to drive Grover's car to and fro, and all around, in pursuit of the elusive, uncanny pair--or had the man left Doctor Ryder elsewhere?--Roger made the routine photographic study of every place that could give a clue to that almost spectral arrival, manipulation of a safe, and retreat. If only, Roger thought, as he made wide-angle and micro-lens exposures, if only Tip, excited, had not fumbled that switch! Had he gotten the lights on a few seconds sooner, they might have seen what was going on, or could have seen the departing figure. If someone had been set to watch down cellar! If----! No use bewailing the past. No use wishing the past could be altered. Doctor Ryder was evidently a prisoner. His gem--the Tibetan jewel, was gone. The Voice of Doom had spoken, but it had apparently turned out to be some person known to the doctor, whom he had recognized, and had identified for them. Tip came dashing back. The car had been taken. Later a policeman returned the abandoned vehicle, and Tip had more photographs to make of its wheel, door-grips, seats, pedals. Tracks in the soft smeared stuff with which Grover had made such clues possible, they found in plenty from coal pile upstairs and straight to the safe, and, less defined, returning cellarward. Only one set! Great, over-size tracks. Defeat again, as Roger realized. Someone had worn huge boots! The shoe-size was unguessable from those elephantine clues. Gloves, as well as boots, left them no usable evidences. Roger, turning over to Tip the final stages of his work, went to Grover, who sat in the screening room, as dawn broke, and brooded. It seemed to Roger that his clever cousin, so often hoodwinked and made cheap by some seemingly more astute operator, was discouraged and certainly baffled. "Don't lose heart," Roger urged, "we'll get everything to come out right. All you need is one tiny hint of the truth." "I must have a dozen," groaned his cousin. "What good are they? My wits seem to be fogged." He looked disheartened. "I can't get my old sense of proportion. Everything seems crazy and impossible. You can't enter an electrically sealed room! You can't open a safe protected by water-jets and high voltage streams. You can't take camera pictures of animals jumping around where no animals are visible to the eye!" "_I_ can't," Roger tried to be jolly and pretend to make a joke. "But _you_ will see how somebody else did. When we had that mystery about the revengeful man who nearly sent a chemist crazy, all you needed was one hint. I happened to be lucky enough----" "Smart enough!" "Well--I caught the sound that got me named the Ear Detective. I'm going to live up to my reputation." He crossed and stood in front of the downcast cousin. "_You_ solved the puzzle. You were called, in magazine articles in true-mystery write-ups--and by the newspaper men--the Mystery Wizard, who solved scientifically from one tiny sound-clue that haunted-laboratory thing. You'll do the same with this." Grover failed to snap out of his dejection. "You run up and get out your requisitions for needed supplies," Grover suggested. "I will check up that Clark man, and try to work out a course of action." Roger obeyed. His work was light, and after laying out dark-room supplies, a set of new distributor points and a replacement insulator on their high-voltage transformer line, and a few other needs, he sat down to try to think out some way to help Grover. With pencil and paper he carried out a decision made during their chat. In a list, on the order they had come, he put down the sounds he thought might be important, and even those that did not seem to have any bearing on the mystery. Opposite them, he set down as many interpretations as he could figure out. His list, finished, he scanned thoughtfully. It ran: _Sound_ _Meanings_ Clicks and hisses on Claws on glass cage. Rats clawing at the film. glass inside to get out. Might be a clue to something. A faint click in A distant relay switching in on a heating headset. oil-burner. Some electrical device somewhere. Does not seem much because it didn't have any effects after it. A thump in the corner Some trash in the corner shifted. A film in of the upstairs room its can shifted. The wall contracting. before I started the Plaster fell. It started me taking pictures camera. that turned out to have animals, when none were there, but I do not see any bearing on our case. The Voice of Doom. A hoarse voice coming from a room with nobody there. Ventriloquism. Important, but how? The Voice of Doom's cry. Either somebody screaming and being tortured, or somebody pretending it. Or some natural sound like a fog-siren. Must be important. Might be a clue to some place or person. The last two on a Both sounds just like before and clear. Same record. meanings I think. Must be clues. But how? The record of same in Like the others, only rougher as if it had Dr. Ryder's room. been made with the needle out of exact adjustment, but strong sounds. The Doctor's voice Had waits between sentences. Was his voice, after the Voice of though. Other one answering not audible Doom. with 3 stages audio. Ticks or drip-drip. Must have been safe combination being operated. How would it be known? Not to a stranger. Doctor Ryder couldn't get it. Grover leaves no memoranda on it. Both alarms at home at Can't mean anything, know what it was, but it start. was a sound-clue in a way. No fire. Why did fire alarm go off? How start? Monkey? Kangaroo hitting it with paw? He seemed not to remember any more. He studied his list, trying to find others to add, new interpretations; but to no avail. He thought that if he tried increasing and adding radio-frequency tuning and amplification to his speaker-circuit--make it a regular radio, in fact, he might get any possible radio sending if that could account for the silent spaces on the last record. He made his circuits up, set the electric pick-up over the start of the record; but with the new hookup he got no new slant. Only one small addition to his list of sounds, bringing his total up to eleven sound-clues--possibly--was the little thump, or thud that the needle transmitted before starting in on the voice with no speaker answering in its silent waits. Roger could get no further. He took his series of eleven sounds, including the alarm bell and the thump that could have been a tiny flaw of the record just on the sound track, and went to Grover. "Here are the sounds," he declared. "Maybe one will clear up all your tangles." At least, studying the list, Grover was more alert, less depressed, Roger saw with relief. He examined the last-made record for the fault that made the odd jarring of its recording. No flaw showed, even under magnification. "It's actually part of the record," he got Grover to add to his list of notes; and then he said to his cousin, "it may mean that the locks went off, somehow, just there." "But it doesn't record the re-locking, so that doesn't fit." "If only we could see any cause for that thumping sound," Roger reflected out loud. "We might have one more real clue." If only he had been able to decode the key hidden there! Chapter 12 DETECTIVE ROGER After further consideration of the sound clues, and discussion of the uncanny appearance of animals on a film, and other points, and without seeing any light, Grover rose. "The staff will be arriving any time, now," said he. "Let's look up that fellow, Joseph Z. Clark, because I want you to do a little Sherlock-Hawkshaw work if we locate his address." They took first the telephone book. He was listed, and his address was in a section of the suburbs given over to large private estates. His business also was listed. He was a jeweler, and the reason he could own an estate was shown by his business address in fashionable Fifth Avenue. "A man would seem to be a suspicious character loitering around a private estate," Grover looked up, "but a boy----" "I could wear my old sweater and cap, and ride my bicycle, and it would be natural for me to rest anywhere along the road, or even go anywhere to ask my way." Roger caught the spirit of the idea. "I merely want you to 'look over the land,' and see how things look," Grover insisted. "Then after the staff goes, come back and report. That gives you time for rest between riding out and back." "After the staff goes--Do you still think?----" "I have to think everything and nothing until I get a lead." Roger took his time riding the dozen miles to the easily located point of espionage. To get there by mid-morning was best. The estate itself, walled in with ivy-covered stone, quite an extensive acreage, he reached as the sun approached the zenith. Near what seemed to be a servants' gateway he sat down by his reclining bicycle. From the grass beside the gateway he could see, along the driveway, the beautifully rolled tennis court, the sweep of lovely lawn, from the main gateway, winding up to a grand, white mansion, people moving about on wide verandas or swimming in a distant pool. "Pretty swell," Roger told himself musingly. "Not the sort of a place to look for kidnapers or jewel thieves. Unless--as Grover is always so fond of saying: 'I dig past appearances that can be falsified, to the heart of truth that can't be changed.'" He turned it over in his mind. Of course, it would not be past reason that a prosperous man, with a millionaire's residence, might smuggle gems, even make a man his prisoner to secure a gem with the world-wide reputation Doctor Ryder had ascribed to the Eye of Om. Om--Roger had looked it up--was the reverent name by which the Tibetans referred to the All Highest, to Our Eternal Father. It was sometimes spelled A-u-m, also, he had found out. From his view of the rich, scintillating gem, the unbelievably many, tiny, flat, facet surfaces, turned in every direction, well symbolised the name, the Eye of Aum or Om, the All-seeing Gaze of the Supreme God. Well, for that jewel, what would not some characters do? He wondered, gazing idly, behind which window Doctor Ryder might be a prisoner; and he thought how he might discover it. If the man could look out, he thought, Doctor Ryder might give him some signal. He stood up, pretending to stretch, facing the house. He got up on the wall, and knew that he was noticed, for a footman moved out toward him. He jumped down, watching the upper windows. No response. No signal. If only he could be seen from all four sides of the house, he reflected, it might be different! "Private property, son," said the footman, arriving at the gate. Some remembrance of detectives who had "taken the bull by the horns" and had "bluffed" people into telling the truth, who had tricked suspected people into revealing things they tried to hide, made Roger act without fully canvassing what the possible outcome might be. "Private, yes," he said, grinning mysteriously, "but you'd better ask Doctor Ryder whether I'd be called a trespasser or not." His bold stroke brought him a revealing response. "Huh? Doctor Ryder? Do you know him?" "I know him," Roger said loftily, "better than he knows the Eye of Om." "The what of who?" "Oh, of course--I ought not to have mentioned----" Roger pretended to be disconcerted, "I--uh--well, never mind." "How comes it you're out here? Why'n't you ride right on in if you want the Doctor?" "I just stopped to rest." If Roger's words were carelessly intoned, his heart was doing speed-pulsations. Doctor Ryder was there! "Well, all right. They didn't know who you were, climbing on our wall." (_Our_ wall--Roger hid a grin.) "Guess I'll walk up. Want to bring my machine?" Might as well enjoy some of the luxury of having servants to wait on him, Roger chuckled merrily to himself. "Certainly, sir. You will find Doctor Ryder with Mister Clark, over beyond the pool, at the first tee of the golf links. Or, would you rather be announced?" "'Station O.B.Y's,'" Roger pretended to be a radio announcer, playing on the phrase, "Oh, be wise," as he shook his head. "No, thank you. I'll go see the doctor without being heralded." He walked ahead of the servant, across the lawn. Before he had passed the girls with gay frocks, joking with their escorts, and the quartet of laughing, splashing swimmers, he saw the man he had supposed to be a prisoner. Doctor Ryder, his bald head and plump frame easily discernible, was certainly as free as the tall, sallow, thin-cheeked, hatless man in white flannels who was swinging a golf club over a ball. "Why--Roger!" The doctor, turning, recognized him as he approached, "How'd you locate me so soon?" Roger, coming up, on guard, hiding his surprise at the unexpected freedom of the man, took on a careless air of wisdom. "Science!" "Oh, you laboratory people!" Doctor Ryder smiled. "So my voice _did_ make a record." He turned to the other man, "I told you that disconnecting the selenium cell wire wouldn't stop the sound from getting onto the film, any more than you could stop the motor, even if you did keep it from taking your picture by holding the card by a rubber band snapped over the lens barrel." The other man laughed. "They may have your voice, and welcome," he chuckled, giving the rather flabbergasted young detective a cheerful grin of welcome, "but they didn't get my picture, and they won't have my voice, because--well, young man, how do you imagine I beat that?" "Wrote your answers," said Roger after an instant of thought. The man nodded. "I told you he was clever--who wouldn't be under the Mystery Wizard, as his older relative is sometimes referred to." Doctor Ryder slapped Roger's left shoulder. Roger, cautious, eyes alert, saw no signs of duplicity. The situation puzzled him. After all of the mysterious, baffling, weird and unexplained circumstances, after the strain and excitement, here was the victim of capture and jewel robbery, about to play golf, laughing, free. Were "appearances" cheating his common sense? He decided to pretend to accept conditions, but he watched alertly for clues. "But I expect you are surprised to see this situation," the man who owned these acres of wealth declared. Roger could not dissemble well enough. "No fair keeping him in the dark," Doctor Ryder prompted. "I was going to telephone, but we had some details to work out over a few holes of Scotch Croquet," he laughed at his own allusion to golf. "So you sleuthed me anyhow. Well, let's put our cards on the table." "All right," Mr. Clark--the footman's identification--said. "I was getting the Voice of Doom manifestation again when--how, only he can reveal--this old traveling chum, who has gone further in making money than I have in curing spinal disease," Doctor Ryder was speaking, "stalked into my room." "Well, I knew you were in danger," the other remarked. "So I just went in through a cellar window and up the stairs, and just as the Tibetans were getting the hang of the slotted cable trick to shut off the current so they could walk in, I knocked down the ring-leader." Could that have been the thump on the record, Roger asked himself. "They had a copperized gadget, and so I chased the other two, and used the gadget, walked in, and brought my old chum out here." "You might have saved us a lot of worry," Roger spoke abruptly. "We thought all sorts of terrible things about you, doctor." "But I said, at the end of the record, that we would go to the safe, and if all was well there we would come here and communicate." "The record ran out before it was spoken," said Roger, and he added: "Well--did you find the jewel safe?" "Just as Clark drove us up near the laboratory," Doctor Ryder informed him, "we saw the Tibetans emerge. How they had worked it is beyond me. But we let them start in a car, trailed it, and when they got out we jumped them, and after a tussle, sure enough!--they had this, so we took charge." There, in his palm, lay the great, flashing emerald! "Matter of fact," Clark spoke up, "as long as your laboratory Chief won't help my friend to restore this to Tibet and escape all the danger--and worse--that those Tibetans can stage, I am going to finance his trip back to Tibet, and may even go along." "All right," said Roger, swinging on the soft turf, "I'd better tell Grover to stop worrying himself about your protection and all." "You can call from the house--a servant will show you where," the estate owner suggested, and Roger saw no trickery or exchange of glances to tell him anything was deceptive in their manner. "While you are telling him, if you like the idea, you might ask if he can give a good young radio operator a leave-of-absence to go along. We have had a Roger, the Ear Detective, so far. We'd be willing to pay expenses and salary to a Roger, the Scientist, on our trip to restore a priceless religious symbol." Roger's jaw dropped, sagging with his astonishment. "Straight goods," added Doctor Ryder. "The Tibetan priests are bugs about scientific cleverness. You'd be a help." "Name your own salary, too," added Mr. Clark. Roger may have set his feet on greensward; but to him it was as if he walked on clouds. But he did not ask Grover over the telephone. _He_ was not so sure about that frank offer. Chapter 13 SCIENTIST ROGER Brought back to the laboratory in Mr. Clark's car, with one of the servants delegated to drive the estate carry-all in with his bicycle, Roger got a new surprise. Mr. Clark greeted their bio-chemist and their electrical specialist, respectively Mr. Zendt and Mr. Ellison, as long-missed brothers. "We attended the same technical college," he told Grover. "And did we have experiences in India?" chuckled Ellison. To himself Roger thought that here was some likely link with the kangaroo and, perhaps, with the ape of the first startling night's alarm. He kept his thoughts behind his lips. "But why must you restore the Eye, at so much risk?" Grover, put in possession of facts already known to Roger, asked, "Turn it over to those mysterious Tibetans who open safes and enter sealed rooms." "That's the rub," Clark declared. "Are they genuine priests? Or thieves?" "The Voice of Doom is a genuine manifestation, apparently," Doctor Ryder added, "at least, in the mountain temple, I heard something similar to the screaming doom. In some way they produce that noise, on a much greater scale of volume. It is said to be the Voice of Doom, and is supposed to come through the lips of their image of Buddha, as an omen, only when a criminal is being judged by the image, which is to say by the temple priests--or before some calamity such as an earthquake or famine year." "But maybe these fellows are using that, and pretending to be priests from the Forbidden Land, to scare us into giving up the gem," Mr. Clark argued. Real priests, bent on revenge, he insisted, struck first, spoke afterward, if at all. Or, these might be of some other sect or lamasery, as they called their mountain retreats. "I can see that," Ellison agreed. "It is not from them so much comes the danger to Ryder," Zendt was also a champion, "More from the hidden menace of the real Doom comes it." "If I could get away," said Ellison, "I'd take back the thing for Ryder." "It is my risk. I got into this thing." "But why do you suggest taking Roger, Doctor?" Grover asked. "Several reasons. First: he has proved that he is accurate in discerning the correct interpretation of sounds, which leads to the next: he is clever at photography and other scientific means of getting accurate data. To explain that, let me say that with so much danger if it were known that I meant to get into the temple, a secret way to restore the Eye would be safer. "There is a hidden way to enter the temple. I do not know it, but I feel that in some way it may be connected with that Voice of Doom, and Roger could photograph, enlarge his takes, study them, and with his sharp eye and keen wit, could no doubt find the secret." "A last reason," Mr. Clark added, "is that he can operate a radio-telephone, as well as send wireless code. We might want the former, if two parties, separated, needed to keep in constant touch. The latter, short-wave sending and receiving, could keep us in touch with the outside world--even with you, Mr. Mystery Wizard Brown." Put that way, there seemed less to make Roger uncertain. What an adventure! "If you could spare that husky, loyal general assistant, Potts," suggested the doctor, "we could ask no better guardian for your cousin." There was much to be considered; there was much apparatus to be designed and assembled, including compact, tiny cameras, hand-operated generator to supply current where electricity never had been used, light, but powerful step-up transformers: there had to be clothing and other traveling needs in sparsely settled Tibet to be planned. Time, though, coupled with a spirit of eagerness, helps in such plans, and it was soon time to say good-bye, to wave from the moving train, to hear Tip shout, "At last we got everything coagulated. We're off!" and to settle back in a parlor car seat until time to go into the diner. Across America, and on the ship bearing the party toward the International Date Line in the Pacific where one day changed to another by the simple process of crossing the imaginary line--the way that the astronomers had worked out to adjust Time to the sun's progress--and even when they landed in China, only slight evidence had been noticed that the effort to secure the gem was still alive in some one's mind. Doctor Ryder felt that it indicated that the Tibetans had really been the ones after the Eye; and the ransacking of a despatch box, in their hotel room in San Francisco, he thought, had been the work of an international jewel thief. Roger, while they crossed the Republic of China from Shanghai, had plenty to interest him, and so did Potts. That loyal if uneducated guardian voiced his astonishment at the unusual sights and experiences. "No wonder they say these people are backward," he told Roger. "They do everything hind-side-first. Men wear skirts and women wear pajamas. They build a station where there ain't any railroad at all, and have roads where there ain't any traffic to use 'em." "Well, to them that is their way. They think our way is back-ways." "It is all in the point of view," Mr. Clark took part in the chat. "Everything depends on how you look at it. The moon looks far off if you reverse your telescope, yet a star looks closer from the right end of the same instrument." "I don't care," Tip was stubborn about his idea, "They _are_ a backward race. Look at that!" "That" was a rickshaw boy, drawing his two wheeled carriage with two American tourist women in it. The boy deliberately swerved and ran across the street just in front of the automobile, the traveling companions and Roger were using. The driver had to stand on his brakes. "They think devils chase them, and if they turn right-angles and run in front of something, _it_ runs over the devils that can't turn corners." Potts was disgusted. Other strange customs--strange because different from American habit--kept them alert and amused as they progressed toward the place where arrangements had been made for the party to join a caravan that was on its way across Tibet bearing tea and other Chinese goods. It seemed safest to go into the restricted territory as if bent on passing through it. Camels, with great fuss and grumbling, swift ponies with many whickers of eagerness to gallop rather than walk or trot, got under way and Roger, swaying on his Ship of the Desert, bound, seemingly, for the Kybur Pass and India, smiled as Potts found his curious steed inducing a seasickness that made him prefer to walk a good part of the time, unless the pace was too swift, when Tip rode and suffered. As arranged, at one of the halting places, during the night, the quartet, met by guides and bearers as arranged for by the caravan leader, quietly forsook the caravan, and rode, on wiry ponies, into darkness and a land over which brooded the mysterious, terrible Himalayas. Far away, in a city laboratory, with Roger's chum, Billy Summers, an expert radio "op," Grover tuned a set, amplified, increasing output strength; and then, as Roger, in the Tibetan night, increased his own signal power as Tip ground at the generator, each knew that with the other all was well. Yes. Just then! Chapter 14 CAPTIVE ROGER Across the Tibetan plain, with its sparse vegetation and occasional small and always distant group of rude huts surrounded by the grazing herd of the tiny community, the party made its way uneventfully. Steadily the ground grew higher. Constantly the Backbone of the World, the great, forbidding, brooding Himalayan range, was a larger part of the landscape ahead. The guides, through an interpreter whose English was almost minus, but who could understand Doctor Ryder's pantomime and few recalled Tibetan phrases, had agreed reluctantly that they would avoid settled parts and keep away from villages. His hesitation was due, as was explained, to the greater danger of being set upon by bandits, or rough peasants who amounted to the same thing. Yet that experience came. At dusk, as they ate tinned food and the natives laid aside packs, cared for the wiry ponies and made camp, the chief guide discerned the approach of a dozen riders, galloping their sturdy mounts in a cluster toward them. Tip, with a grunt, snatched at his revolver. Mr. Clark, almost in a snarl, ordered him not to show it. "We must be diplomatic," the man added; and Doctor Ryder agreed. "Roger," he said to the excited, trembling young scientific representative, "can't you get something ready that might startle them or look like magic?" Roger, in spite of his misgivings, thought hard. "Come here, Tip." Together, conferring, they unpacked equipment. As the silent, but menacing horsemen deployed and surrounded the camp, the youth drew on, hastily, heavy rubber gloves. Tip, not too sure that he ought to be so far from his charge, obeyed stern orders to carry out Roger's instructions, and in the tent, sat by the handle of the generator. The small electricity-producing unit, much more powerful, though no heavier than an automobile battery-generator, had its handle and flywheel geared at a high ratio, so that moderate turning rate gave the armature its correct impetus for best results. From it, unseen in the darkness that came on, a wire ran to a spot where Roger crouched, apparently busy with cooking utensils. The bandits dismounted, and the group advanced, completely surrounding the white men, who wore the native coats of rough texture but who did not attempt to disguise their race. The natives of the camp were evidently expecting the raid, and Roger was sure that either the chief guide or an aide had betrayed them. It was too late to avoid the encounter and recriminations were not wise. "You give all money," the interpreter told Doctor Ryder as the leader of their adversaries spoke in guttural phrases. "Tell him we are scientists, going to study the great rocks. Tell him that we have no money, and bid him go, before we ask our young magician, who is close in the councils of the Gods, to smite them." The interpreter apparently gave the interpretation faithfully, from his gestures toward Roger; but the man he addressed gave a harsh laugh. He spoke to his men and they roared and shouted in mockery. "Bid him go, then, and try his strength to capture that small youth who cooks the broth that gives him the strength of the Mountain Gods." As Clark gave the phrases, he glanced at Roger. Probably, Roger thought, the man was afraid that he would fail at this critical moment. Be afraid. Or show nervousness. The bandit leader guffawed, and strode rapidly, and menacingly, in Roger's direction. "It's your move, son," Roger mentally admonished himself. "Steady." To Tip he called, very low, "Get set." Tip called back, "Say when." The bandit strode close. "Om, man-u, pad-mi, om," muttered Roger, using the prayer so familiar to all Buddhists in Tibet. The man paused, looking a trifle surprised at the sound. Roger, upsetting a pan of water on the earth, rose, standing near the wet space. In words taught him by the interpreter, he spoke. "What do you seek?" his phrase demanded, and his voice he kept very steady, even stern. "You!" The man, depending on surprise, made a quick grab, as Roger laid aside a fork and with apparent aimlessness, paying no heed--outwardly--took in his right hand a big iron ladle to stir the boiling soup. As if unaware of the plan to attack, he went on, "Om man-u pad-mi om," knowing that the first utterance had started Tip to whirling his generator armature. The man made a grab. As though turning, Roger maneuvered so that his ladle was just where the man made the grab--but Roger was beyond the wet spot on which the man stepped. Stepped up to stronger voltage, carried along the wire fixed to the ladle handle held in his rubber-gloved hand, Roger was immune to the current that had better conductivity through the man standing on wet earth. As his hand closed on the metal, with a startled, frightened howl, the bandit writhed and was convulsed, more by surprise than by any vast voltage. It was enough to jar, not enough to harm. But he could not let go. "Cease firing," Roger called, amused as the man was contorted by the tingling, nerve-throbbing current that he could not understand. The others, standing with mouths agape, saw their leader fall back, in awe, rubbing his arms. He spoke abruptly, staring at Roger unbelievingly. Then he drew back, and discussed his experience in guttural grunts and abrupt gestures. Roger, knowing that the generator was still, stirred the soup nonchalantly while the interpreter, on whispered instructions, put a brave front on the situation and demanded that the group go away before all should feel the stronger wrath of their super-man. They did draw aside, conferring. But they would not go. They took their mounts, but sat on guard. Roger, eating with his companions, suggested that if they could demonstrate some visual marvel, such as a picture projected onto a light-colored tent side, it might frighten away the men. The guides did not think they would be bothered, the interpreter said. The men would not go. They would stay on guard, and by keeping the party surrounded, not molesting for fear of more harmful acts, but still preventing them from moving, the bandits would wait for instructions from some one in higher authority. A messenger had ridden away. Shortly afterward, while they sat around their fire of native fuel, they saw, approaching, the messenger and another tall Tibetan who dismounted and approached. He wore the recognizable garb of a Lama. "Show me your magician," he commanded. Roger, assuming a brave air, arose. "Come," the man beckoned, "you will show me your wonders. I will show you mine." "Better go," whispered Clark. "He will take you just where we want to get. Take Tip, and a radio, the battery set. And keep in touch." Chapter 15 IN THE LAMASERY If the urging of the jeweler and of Doctor Ryder seemed like sacrificing Roger, they assured him that it was not so. The lama, they declared, was interested in anything seeming to be occult or mystifying or a use of hidden forces. His attitude was not menacing. Rather, it seemed friendly. And he was a lama from the very temple they sought! "What a break!" Tip, whose companionship the man readily agreed to, as Tip carried the portable battery, compact five-tube set, telephone instrument and spare B. battery, spoke under his breath. "This will coagulate everything, make it easy," he added. Roger, somewhat excited at the prospect of going into strange adventures, being "on his own," nodded. The man's attitude was respectful and friendly. The bandits stayed around the camp, but the interpreter said that if the youth satisfied his companion of his abilities, it might free them, might even help them to reach their objective. The lama had evidently been at a village not very far away: they had only to walk to that, and then, with much show of veneration for the lama, their holy man or priest, the villagers furnished ponies. Roger, mounted and riding beside his friendly captor, with Tip and his apparatus on another pony and on a led carrier-animal, noted the tiny prayer-wheels by the ascending roadside, saw the other lamas they met with their prayer-wheels and prayer-papers, observed the reverent attitude of the peasants herding cattle or grazing sheep, and felt a renewed confidence in the outcome. The lama could not converse with him, but the universal language of look and gesture served very well between them. In due course, after riding up steeper and steeper paths, into the craggy, ravine-and-cliff torn mountains, they came to a great, dreary, uninviting stone monastery wherein the lamas stayed, studying, praying and conducting the strange rites of their religion. "If you ask me," muttered Tip, scanning the looming pile of stone, "We are a long way from the lab. What's all them little windmills for?" "Prayer-wheels," Roger told him. "They say their prayers with them." "Well if you think I'm going to end up by spinning one of them whirligigs, you're wrong. Tell this bird I'm incontrovertible." "You're what?" "Incontrovertible. I won't change my religion." "Not convert-ible. I see. Still the same old Tip, far though you are, as you say, from Grover's dark-room. But they seem to look up to this man who brought us. He's sort of bossy, too, and they mind." They were made as comfortable as the rude conditions of the cold, harsh life the lamas led would allow. Roger was glad that Tip was not separated from him. They were both given one cell, a gloomy, but not prison-like cell that looked out through its narrow window over a vast, tumbled, fissure-creased series of crags and ravines, cliffs and snow-covered peaks. It was as though the Creator of the world had flung this wild mass of rock helter-skelter, in a long backbone, to hold the world together. Simple, not too palatable food was ungrudgingly served, and their conductor visited them several times to see that they needed nothing he could offer. The radio-telephone, answered by Doctor Ryder, reassured them. The bandits had been sent away by abrupt orders from another lama. Not a can of food or a bit of apparatus had been disturbed or taken. The communicating sets worked well, and things were not so bad. The gaunt, silent, stern-faced lamas served them without comment or objection; and Tip and Roger were allowed to roam at will through most of the corridors, rooms, cells and even were permitted to attend the chanting devotions of the men in a huge chapel-like place. But that, they were certain, was not the "temple" because there was no Buddha of the stature they expected, or with a spare Eye either missing or replaced by an imitation. But nothing advanced. Nothing happened. Days dragged by. The explanation came when their captor, or host, brought them into a sort of general community room, where he presented them before a very sedate and reserved and cold-visaged old man. Roger, however, did not feel any fear, because the man's eyes seemed to hold some deep, broad-minded tolerance. He looked kindly. To their amazement he addressed Roger in halting, but clear English. "You come far." "Yes, sir," Tip spoke first. "You come for what?" Tip hesitated. Roger came forward. "This man and I are with a scientific expedition." "Have you secured permission to enter our land?" "I suppose so," Roger, himself, was not too certain about the details of that official permit that Doctor Ryder said he had gotten. "You understand something of science?" Roger admitted it, not boastfully. Their things were all brought in. "Show me, and tell me." Roger, trying to use short words and simple explanations, demonstrated the radio-telephone, and its purpose of distant communication. He did not want to explain the tiny camera, and put it into the case with the spare battery, pretending that it was part of the apparatus therein. The watching chief lama and the venerable visitor gave no special attention to it and Roger was glad. He had it in case they got near the temple and he could try to discover, from its pictures, later enlarged, how the secret way into the edifice, if one existed, was manipulated. Contriving to "raise" his other friends, by the set, Roger allowed the lama and the other to hear the reply to his guarded declaration that they were being well nourished, made much of, and so on. When the men seemed satisfied and the paraphernalia of radio was removed, the gentleman at the head of the lamas considered Roger and Tip thoughtfully. "Indeed great progress has been made in your America," he said, to Roger, while the lama sat silent. "Even you, not more than thirteen, surely, accomplish what would be wizardry to our own peasants--and yet this Forbidden Land holds locked in her bosom the destinies of tomorrow's science, and knowledge of forces that your America does not dream of. It is a strange old world." "Yes, sir," Roger agreed, not knowing how else to respond, then: "How do you come to know our language, sir?" "Your own sacred Book tells of the--is it not the Tower of Babel?" "Yes, sir." "And is there not the word that prophets, as fire descended upon their heads, spoke 'with many tongues'?" "Yes, sir----" "We, in Tibet, have methods for reproducing many miracles--as they would seem to you, for all of your scientific wisdom. Let me show you." As though understanding what was to come, the lama approached, and under the steady gaze of the other, seemed to assume a trance-like fixedness of expression. Standing, his body was still rigid, but he did not sway or totter or fall. Presently, as Roger and Tip watched, knowing it might be hypnotism, but still marveling at the produced result, they heard: "I am in a great laboratory." And the man used perfect English, not even slightly inflected as had been that of the other, "There is an office with a pair of desks. At one, a woman typewrites. At the other, Grover Brown interviews his staff, and tells what Roger has sent him by the Morse code and which he 'picked up' on four stages of radio-frequency and three audio." It was almost weird, uncanny. Of course, there might be such a thing as mind-reading--but---- "In the chemical division, a man, Zendt, experiments with tissue, and a new--to him--process for causing a medicinal reaction by the application of Ellison's sun-lamp. "But here--Roger fails to tell completely of his mechanism. He forgets to explain the tiny camera with which he hopes to discover a secret way into our temple----" If Roger's face was controlled in time, perhaps Tip's was not. The older man smiled, a little wryly. "That will do." He clapped his hands sharply. The lama, with a somewhat dazed look, flexed his muscles and stumbling to a seat, collapsed on it. Magic? Trickery? Roger had no time to decide. "If you are so anxious to learn our secrets of the temple," remarked the old man, "you shall have them. Indeed, you shall even hear----" Roger grew tense as he paused and then finished: "The Voice of Doom! Come!" Chapter 16 THE IMAGE SPEAKS With an abrupt change the atmosphere seemed to be charged with electricity. Of course, thought Roger, trying to remain cool, it was merely his fear of the outcome that made his nerves tingle. There was no time for any choice of action. Rising, the old man moved toward an arched opening at one side of the stone chamber. Tip, fierce-eyed, loyal, beside Roger, realized as he tugged at his empty holster that in some clever way he had been disarmed. A glance behind him showed the mocking lama, holding his own weapon. Tip gauged the chances of a leap, shrugged. It was useless. Monastery attendants were at all the open doorways. "Buck up!" he whispered. "It may not be so bad," Roger tried to reassure them both. They followed, as follow they must, down a long, echoing, empty corridor. Far away, low, weird, they could hear male voices, deep, rather disturbing in tone, chanting some uncouth succession of notes. Their slow walk behind the aged conductor brought them constantly nearer to the chant, for the voices grew louder. At a doorway, heavily shrouded in lustrous woven velvet or other drapery, the guide swung, and an attendant, bowing, moved the cloth to one side. The chanting swelled suddenly. Resistance was futile. As the guide moved aside, motioning, Roger, and Tip after him, passed under the great stone door-lintel, into a large square chamber full of the chanting lamas. And at the end, in a niche, on a sort of raised dais, sat the huge carved wooden image or statue of the Meditating Buddha or prophet of their religion, and in its forehead glowed, in the flickering torchlight, the great, green duplicate--it appeared--of the Eye of Om. At first it flashed through Roger's mind that this was strange; but at once he realized that, of course, they would have replaced the gem with a substitute or an imitation, and would not tell many of the loss. Thrust forward by the lama who had brought them there, Roger and Potts were ushered down the aisle between rows of kneeling, low-and-mocking-voiced monks or lamas, to the space below the great figure. Words in Tibetan, answered by hoarse responses from the crowd, seemed to be some ceremony or invocation of judgment, in which, they sensed, the two white people were the sacrifice or center of the rite. Standing silently, Tip was watchful but helpless. Roger, too, kept an alert mind but saw no means of escape. "You seek to hear the Voice. You wish to know the secret." The venerable man who appeared to be some sort of super-lama, to whom even their former captor deferred, knelt and pronounced some low, weird and long-winded invocation. At his gesture they both knelt, submissive if not willing, and he bowed his head to the floor and stayed that way. All the rest were in similar positions. And then, blood-curdling in its startling suddenness, after an interval of suspense, there came, but not softly or in small volume as in their recordings it had been, a scream that was as weird as the howl of a soul in torment; and after it followed, louder, but duplicating, the decreasing pitch and growing volume of the howl, roar and groan, that ceased abruptly on a hoarse note. Apparently, and they all seemed to believe it, the Image had spoken. Certainly, to Roger, still able to be alert enough to trace sound, it issued from the head or face, possibly the small, slitted mouth of that statue. "The Doom has judged," the old man told them in precise English, but in a very formal and cold tone, "the judgment is pronounced. I am to show you our secret and allow your science to prove its worth." A mocking twitch took the place of a smile as he added: "Or, from our viewpoint, its worthlessness." As he spoke, with no sound an orifice opened in the wall behind the idol. In its cavernous depths, dark and forbidding, Roger guessed that the stone had withdrawn up or sidewise, or had turned on a pivot. He and Tip, hesitating, were prodded gruffly forward. Into the decreasing light they moved--were forced to move. The darkness became abruptly intense. The noiseless door had closed! Echoing still to their last footstep, the silence slowly became complete. "Science!" grunted Tip, "Without no scientific impediments." "Implements." Roger spoke from habit, still too dazed to feel, with completeness, the horror that must soon come. And far away, the last exhalation of the "s" he had spoken was flung mockingly back by echo, a hiss of multiplied duration, fainter as it echoed to and fro. Trying to hold calm, Roger felt an impulse to scream, to beat on the callous stone, to beg for mercy. Instead, feeling that Tip also must feel the dread he felt, he nerved himself to be not only calm, but matter-of-fact. "Well," he remarked, "We've heard the Voice and found the secret way. And that's that!" Chapter 17 BLACK SILENCE Without looking up from the radio over which he was fussing, Doctor Ryder spoke snappishly. His nerves were on edge. "We ought not to have brought him." "But he was so clever," protested Clark, "and surely if anybody ever could interpret what that temple must hide in that queer sound, he'd be the one. He interpreted claws on glass, you said--and----" "Be still. Let me listen." The doctor fidgeted, trying to tune, to amplify, to adjust knobs on the unresponsive radio set. "We had no intention of getting him into hot water," Clark said, morosely. "We did want to get into that temple. The bandits were unforeseen complications; but when the Lama came, I thought that for Roger it would all be simple, once he got into the lamasery." He watched a few minutes. "Can't you raise even a whisper?" "No! And it has been three nights. And besides we can't operate the wireless, because you don't know code. Brown, in America, will be wild. Our three days of uncertainty is nothing. He hasn't heard since Roger left us, and that was a week before our last contact with him." "Let me try. You go and turn the dynamo." "I wish I knew more about it. I know precious little, come to find out, whether it's burned out, or the brushes gone, or how to adjust these things." The doctor relinquished his place, went into the tent. At the tuning dial and control knobs, as he whirled them and almost frantically called into the telephone transmitter, Clark worked. In the tent his companion swung the flywheel over, and around, and then stopped, groaning. "Guess we are licked," he came out. "You go back. We'll keep trying." Doctor Ryder nodded. Ten minutes of silence. "I'm--sh-h-h!" Clark tuned delicately, getting the "hang" of the controls. Out of the receiving diaphragm issued a low, male voice. "You will return to your America." Desperately Clark swung the switch to the sending side. "Who are you? Where is our boy? Roger? Is he there? Is he----" "He is gone. The Voice of Doom spoke his sentence. He has learned the secret of the hidden darkness." "We'll have a hundred thousand American troops in your darn country if that boy has been hurt----" The other end of the transmission mocked with a hoarse laugh. That was all. Doctor Ryder, informed, looked defeated. "And all for a tawdry jewel. And we still have----" Clark motioned for silence, trying desperately, vainly, to raise a response from the dead ether waves. They retired, at last, because with the glowering clouds hanging low in a star-obscured sky, with possible guards in sight, they dared not make a move. Discussion had been fruitless. They had drawn only blanks in their search for a course of action. Clark, lying on his cot, tossing, got up. "I can't sleep. I'm going to walk around--see if I can think up some way to find out about Roger--and that man with him, too, of course, because what happens to one will happen to the other." He went out into the somber blackness of midnight. Walking did not keep him from brooding, nor help his brain to do its task. He sat on a large tussock of dry turf. "For a tawdry gem!" he muttered. A slight sound made him leap up, revolver drawn. Had it been the ever-blowing gale, stirring something? Or some fresh menace, some creeping creature, some vindictive priest, who had made that tiny sound of a scraping shoe? "Who's there? Speak or I'll fire!" He knew no direction to shoot in. But the light might disclose something. He raised the weapon. "Mr. Clark, don't----" "_Roger!_" "In person, and not a ghost." In a heavy sheeps-wool coat, shaggy and rough, the figure came to his side. His grip of the young hand was sincerely strong. "Quick!" Roger gasped, "give me the Eye of Om--I can exchange it and get back and we can go before they discover me." "Where have you been?" as they walked fast toward camp. "What happened?" "They tried us, and the Voice of Doom sentenced us, and they put us in the chamber behind the image. But we can't stop to talk." "Are you all right? Is Potts safe?" "Yes. Yes. Hurry!" "Let me go with you." "Only hurry, and bring the Eye." Dashing into the tent, scattering explanations to befuddled Doctor Ryder as he broke apart the small secret compartment in a bedroll and got the gem, Clark met Roger and handed him the stone. Instantly Roger fled into the darkness. When Clark overtook him he saw Potts holding two ponies. Sending Tip to camp, the pair mounted and galloped away. "It was easy to find the secret," Roger said as they made a quick ride toward the distant cliffs, "Tip helped me keep my head. We figured out that somebody worked the Voice, and it was louder than human sound. We were in a tunnel. It sloped downwards. It seemed as though the Buddha image had howled. That meant a way to get into the image or open a port from the tunnel to it. Phonograph records wouldn't have been their way. "The wind always howled around the lamasery, up so high. From what we knew about acoustics and how they shaped the old phonograph horns to increase sound amplification, we worked it out that we were in a sort of wind-tunnel or horn, and it didn't seem that they opened any rock at the image or we would have heard it. If the far end of the tunnel opened, and wind howled in and through the hollow image, it could make those weird howls, high and low, moans and screeches. So we followed the tunnel down, and by using Tip's pencil flashlight we located a lever, and risked making the sound. But we got out." By reversing the method, he and Mr. Clark also got in, and with the older traveler's wisdom they found the trick of getting into the image, and saw that when the way was closed, the tunnel did not make it howl. Also, from the eye-places, they made sure the temple was deserted, and soon enough the change of gems was complete and later, blocking the lower door lever with a wedge of stone, they prevented pursuit from that direction and eventually reached camp safely. On the way Mr. Clark discarded his now useless Eye taken from the prongs, and Roger, at last safe, with a plane radioed for, slept and dreamed that he was being awarded a medal "for 'sound' wisdom." "After all," he said in his dream, "my deduction was 'sound'." Chapter 18 A LETTER ROGER HAD NOT SENT Reunion with Grover and the laboratory staff, was, as Tip put it, "the best part of assimilating Tibet." He explained that he meant "taking in" the country. Roger agreed with his spirit if not with his choice of words. It did give him a little twinge of dismay, a slight blow to his vanity, to discover that during his absence Toby Smith had been put to work in the stock and supply department. Toby Smith, who had sold them the priceless emerald Eye of Om for a movie camera! At once Roger pushed away the feeling of disappointment and did not let it become envy. This world and its work, he realized, had to keep moving, no matter who dropped out. Instead of being hurt, he dismissed his emotion by telling himself that it showed that any person, no matter how able, could be replaced. The important idea to have, he told himself, was that if one made one's self so capable as to be missed when away, more than that could not be done. After a while he was glad he had not cherished mean feelings, for Toby had not replaced him. He had merely done his best. Roger, as the staff soon let him know, had been missed for his competent way of handling needs, keeping everything neat and available, and being cheerful and useful under any circumstances. "Am I glad you're back!" Toby hailed him. "This chemistry is too much for me. One day Mr. Zendt asks for me to pack some frozen H--two--O around a can of stuff. How'd I know the man wanted ice?" "It takes study to understand the chemical symbols," Roger said. "Yeh. And they have so many things that sound safe, and they're dynamite in disguise. Like a guy wanted some citric acid, and I got picric acid, and I spilled some and was swabbing it up with cotton, and I used it to swab up something else--I forget what, but when I was going to chuck it in the furnace, they almost had a fit. It had turned into lyddite or some other sort of explosive. Looked like the same cotton to me." "I never could get them sodium calorides straight, neither," Potts took up the complaint against chemistry's "cheating" symbols. "They say it's made out of a gas in the ocean. And the ocean's _water_, and here comes gas, and they put metal, mind you--sodium--on top of it, and it turns out to be common table salt." "It's sodium chloride," Roger corrected him, "not caloride." "And they talk the craziest lingo, here," Toby insisted. "Mr. Ellison asked for motor brushes, so I looked, and the only brush I could find was what we sweep up dust with, so I took that. Was he mad!" Roger's return to his duties in charge of stock was acceptable! Grover, when the celebrations were concluded and routine had been resumed, sat down in the private "thinking den" as Roger called his office, and chatted. "We have quite a few new interests," he gave information. "Mr. Ellison has perfected his speed camera with stroboscopic lamps so strong that they beat sunshine. He can't use a shutter: nothing mechanical can be made to work as fast as he wants it to. So he uses alternate flashes of the lamp, and his film runs so fast past the aperture that not even daylight fogs it. Of course you know he was busy with it, but you don't know that he has succeeded in perfecting it, and is studying some amazing chemical and other operations of Nature. "Mr. Zendt has brought in rather an unusual man for us. He was an astrologer--a man who reads 'destiny' in the planets by making a chart of the zodiac for the moment a person was born. He used to sell his 'fortunes' at so-much a 'destiny' on a Coney Island boardwalk. "Now, though, he has turned scientist." His interest, Grover explained, was in studying in a scientific way the reactions of cells, tissues, plant and animal life to various rays of light, heat and other frequencies of vibration. His theory was that as the sun awakened life in the Spring, as the moon partly governed tides, so other planetary vibrations, reflections and modifications of sun rays, made changes in chemical constituents of cells; and if plants were made up of cells, and if animals ate the plants and in their own bodies modified and incorporated these cells, then the rays must act on animals also; and from that, to saying they influenced the bodies of men in some way was not a far step. With telescope, vibration-recorders, ray-filters, lamps and spectrum devices he was carrying forward experiments in the room next to Roger's supply department. "You will probably have to help Astrovox--he says he is 'the voice of the stars!'--with his apparatus," Grover added. The most interesting point to Roger was the fact that nothing new had occurred in their mysteries. "I guess everything is settled," Roger declared. "With the Eye in its place, there isn't any more danger for Doctor Ryder, and I saw Mr. Clark exchange the one he had for it, and even helped. "The big jewel was in a sort of depressed place, with prongs to hold it," he reconstructed the event, "and we found a way to make the prongs loosen, by working out that the gem had to be put in, and it was too finely cut to enable them to hammer the prongs down, so we hunted for some secret springs, and the Buddha image had a finger that could be bent back, and it turned the prongs outwards, so we substituted the real gem and then set the prongs, and all was well." "I am not satisfied about the business, though," Grover stated. "In the first place, although we have explained a good deal, and what you say about replacing the gem is true, some of the manifestations we experienced are sticking in the back of my head. They seemed so--so 'out of character' with what Tibetans, or gem thieves either, would have done." "But if the gem is replaced and there isn't any more need for the 'manifestations,' we won't have any more, and we can forget the whole thing." Grover smiled. "Suppose that a series of experiments were going forward to find a more durable resistance wire for rheostats," he suggested, "and the firm that commissioned us said to drop it, how would you want to do?" "The same as you always do in such a case, Grover. Go through with it. I see your idea." The sound of the Voice of Doom, he asserted, was explained. There really had been such a natural phenomenon, caused by wind let into a tunnel and making the sounds through the shape like a whistle in the tunnel and in the Buddha image. "But how did it get on the records?" Roger was equally unable to answer that. "Besides," Grover insisted, "those priests are curious folk. You saw the gem replaced, and to white people that would end the need for stalking a culprit; but they seem bent on punishing people." "'Seem'?" Roger caught the present tense. "Why, your own letter says so." "My--which letter?" "The last one you wrote. It came yesterday." Grover drew from the drawer an envelope postmarked, as Roger saw, from Bombay. They had come on down the caravan trails, until they had met an English airplane that had been arranged for. It had "set down" on the plain. In that they had flown to India, leaving their stuff to be brought along by the next caravan and shipped home. The address seemed very like his own handwriting--close enough to have fooled Grover, evidently. And yet--he had been on a packet boat, bound for Europe, on the day shown by the postmark. Quickly, startled, he opened the letter. In the same close imitation of his exact, clear script, he read: Bombay, before sailing. Dear Grover, Well, we are homeward bound now. At the cost of a radio and camera left in the Lamasery of the Holiest Ones, I abandoned them. So far, no event has come from my visit there. But of course with the Eye of Om stolen, the Guardians of the Eye may strike. In haste, to catch the mail, I am, Affectionately, Your cousin. Roger looked up. "But the Eye of Om was replaced! I helped." "Then why did you write?----" "I was on a boat when that letter was posted, Grover!" He bent forward, earnest and eager. "Who?--And the Eye was _not_ sto----" His lips closed. His face changed. He remembered something. It was unjust to let it mean anything. But---- Why had Potiphar Potts gone back to that secret tunnel? Chapter 19 DISQUIETING DEDUCTIONS Of all his loyal staff, most dependable, sincere and trustworthy was the handy man, Potiphar Potts. Roger knew that. Honesty compelled him, all the same, to connect the fact stated in that mystifying letter with a fact that had not been important when it had come to him. Potts, on that memorable night, holding the ponies while Roger had gone to Clark, had, as they discovered on their safe return, gone on into the camp. When they had gotten back, to report to Doctor Ryder the substitution for the false Eye of the one they had brought, Potts had seemed uneasy, though Roger had accepted the man's own explanation. "I'm worried about our idea of you leaving the wedge in the thing that works the rock door," he had said, "it sounded good when we made the plan. If we wedged the mechanical levers, we said, they couldn't get out that way and chase us or anything." Roger said he still thought it a sound idea. "I don't, now," Tip had declared. "They may not go in at the temple to see about us for days, and what difference would it make whether the lower end is blocked if they did come down that way? They'd go back, mad as hornets, and we _would_ be in for it!" If they had left everything as before, Potts had insisted, anyone using the lower entrance would suspect nothing, and might not even know they had come out that way. "I'm going back and fix it the way we found it," he had said. Loyal, honest, faithful Tip! Why, Roger wondered, did his mind persist in telling him that Potts had stayed away from camp a long time and why did he associate that with the present threat? Truly enough, he _had_ actually seen--helped replace--that gem. With equal sureness, the note said that the gem was gone. It was no trick of deduction to assume that the note had been prepared by the lamas, soon after he had escaped. They had shown how clever they were at pretending to be able to read his mind, telling about the lab. He recalled that he had kept a record in a booklet, of radio conversations from his portable set in the lamasery to the camp set. They had specimens of his handwriting. A clever man, forging for the purpose of conveying a threat, perhaps planning some harm to Roger on the trip home, had certainly, to all appearances, made the note. Well, his mind ran on, if they had been so sure that the gem was gone, and if they had supposed that in vanishing he and Potts had taken it, the note would be their natural Tibetan way to account to Grover for anything that might have happened to Roger later. Nothing had; but the note had been despatched, with the probable knowledge that the letter, by mail, might get a faster trip, a more direct route than the travelers might use. It had been so. Who besides Potts could have known that the genuine gem was in its place? Not the camp people; and they did not know the secret of the tunnel. Neither Clark nor Doctor Ryder had left camp for any protracted period. "But," Roger remonstrated with his stubborn idea, "if Tip had been tempted to take it, the Eye of Om was available all the way there." His prodding deduction shook that off. Potts would not have dared to try for it on the way to the temple. But--after it was supposed to be in place, so that his party would not know of its abstraction!----Roger fought, but so did his insistent suspicion. He decided not to tell Grover. "I--I hesitated because--well, it came to me that somebody else _could_ have taken it, later. We got away from that locality as fast as we could, and met the 'plane the next day, after I had radioed our agreed signal to a British aviation field in India to despatch it." "We can find out something by photographing the fingerprints on the note, and so on, with routine procedure," Grover dismissed Roger's poorly explained hesitation. "Suppose you let Tip do it." Roger agreed eagerly. A fine way that would be to see Tip's reaction. Roger took him the note with Grover's orders. "Gone? The Eye--gone?" Surprise seemed genuine. And Tip--Roger felt sure--was too slow of wit to act so cleverly as to seem innocent under this surprise. "Glory-to-Grandma!" Potts gasped, "And--I--went back----" "But you wouldn't take it!" Potts made a wry face. "Maybe--maybe--" he seemed to find it hard to go on; but he forced his lips to form the sounds sent up by his vocal chords. "I declare, Rog', if I took the Eye, I didn't mean to." "If you took it--how could you help meaning to?" "I picked up what I thought was the subterfuge----" "Substitute?" "Yes. Thrown away by Clark, I supposed. Like Toby done before." "Where is it?" "I--uh--why--tell truth, Rog', I--I thrown it away. Back in Bombay. I figured it wasn't a safe idea to keep it, after all." So there it stood! Chapter 20 GHOST VOICES Roger's mind was more at ease. He had seen Mr. Clark pocket the gem for which they substituted their Eye of Aum. Outside the rock door as they emerged from the fissure leading down from the temple, he had seen the man's hand pull it from his pocket and fling it away. "That's no good," the jeweler helping Doctor Ryder had chuckled. Definitely, in Roger's mind, Potts had found that cast-away imitation. He had not gone back through the tunnel! "Exonerated," he said, cheerfully, and they brushed a finely pulverized compound over the note, seeking to bring into relief the possible finger-prints thereon. Several faint smudges showed, and Potts made a photographic exposure, also using chemicals, with other takes, to bring up possible marks, erasures and so on. Roger left him at his work, at a call from Astrovox, the scientific student of planetary vibration who had been a side-show astrologer. Joining the plump, bald-headed little man, close to sixty, whose deep-set, shaggy-browed blue eyes twinkled with inward cheerfulness, Roger helped him rig up his seemingly crazy idea of a vibra-spectra-telegraph-o-scope. That was what Roger mentally named it. The man wanted to catch the possible vibrations of higher and lower frequencies than light range. He also wished the various colors showing in a star ray to tell whatever spectrum bands it might contain. Besides, he had to hold this apparatus trained on a desired planet or star, by use of a mechanical movement that enabled him, through a transit's hairlike "sight" to follow a star as the earth revolved. Furthermore, he wished photographs and a sort of seismographic tape recording of vibration frequencies. The nine-power telescope he had to be satisfied with was set up to poke its outer lens up through the skylight over the supply room. All around the smaller, adjoining, partitioned place formerly made notable because of the vanishing rats and the strange voices, he had cages of mice, squirrels and rabbits, under rays from electrical, and other forms of vibration. In hot-house "frames" or small beds under glass he kept living plants, with color-filters straining the light playing on them, to test reaction to heat, light and color. One bed, under a brownish glass, Roger noticed, had thin, stringy, sickly vegetation in it. In one under a short-wave irradiation treatment, plants thrived. In tiny flat, glass-protected trays, specimens of cell-cultures in tubes, and sections of living plant tissue were being exposed. "Guess we'll have to clean out the far corner," Astrovox suggested, "I dumped all the wrappings there. Might start a fire." Approaching to help, he finished his sentence with a chuckle. Roger nodded, and gathered up the papers, making a fine rattle in the process. A glow-bulb lighted in the interconnected tell-tale panel as a small bell rang. Roger, glancing at the panel, saw that the summons was from the electrical division downstairs. He went to the head of the steps. "Want me?" "Yes," answered the voice of Professor Millman, electrical engineer. "We're going to make a flat-table recording. I don't just see where we get power for the motor from." "Right down close under the recording machine table," Roger called down his information. "You'll see an outlet set into the floor." "Oh--thanks, yes. I see." Roger went back to help Astrovox. "Can't risk it, with all the chemicals, and combustible stuff," he answered the former phrases of the old astrologer. "Not with Neptune, the planet, in opposition to Saturn and with Mars opposing Uranus," the old man chuckled. Roger looked as if he did not see the point. "In our belief that the planetary positions influence chemical reactions--and all life is chemical, or, at least electro-chemical," he was told, "we use the known planets as symbols for forces of nature. Saturn, you might say, stands for cohesion--or, better, say for crystallization, because Saturn makes gravity possible, makes density in our earth by cohering its quintrillions of atoms. "Mars we could say is a symbol for the combustion engendered by fire, the same as Uranus is, in a way, a symbol of explosiveness, and Neptune seems to represent a sort of disintegration, diffusion and slow separation of atoms, not by explosion but by attrition." To Roger it was all pretty much like Egyptian hieroglyphics but the man seemed to be talking what he considered sensible phrases. "Let us say that we place a pellet of putty between two machines, one engendering a force like repulsion; the other giving quick, and very high-frequency stabs of current toward the other. The answer might be that the pellet would explode or fly into its atoms. "But," the old man went on, "The force of cohesion would hold our earth together in such an experiment, though the volume or size of the tiny pellet would be too little for it to act on sufficiently to keep the form together. That, in a way, is what so many people misunderstand when they talk about astrology. Properly used, correctly interpreted, it enables us to understand our reactions--emotions----" Roger was in the next room, loading the papers on the dumb-waiter to send to the cellar. As he came back, gathering up more, Astrovox, as if he had ranted along on his favorite topic without ceasing, said: "--fire." He stood up. "Where were you? I was telling about Mars and Uranus exploding things and starting fires." "I have to work." "Yes, that's so. Well, this is your last load." Roger gathered the great heap of heavy wrapping paper, and left him shifting one bed of plants from under a deep ruby glass so that they would be exposed to a pale green color filtration. Going down to remove the papers from the dumb-waiter, Roger saw Mr. Millman finish recording the multitude of gyrations of a sparking motor shaft which Mr. Ellison was photographing with his camera. "We are going to count the sparks," he told Roger, "just to check up on the speedometer attached to the flywheel, which Millman says is off-count by hundreds of revolutions to the minute." "I'll take the record up and have it made ready for a slow playback. I'm going up anyway." He turned it over to Potts as the note had been thoroughly revealed in all his exposures, and had shown no identifying finger-marks. Roger went back to Astrovox, and became deeply interested in the latter's plans for night study of the spectra of stars. "I wonder if your cousin would arrange for one of his men to stay part of the night with me, to take down my data?" "We can set up a dictograph, and let you talk it onto a record." "That would do." "Or--we could mike down from here to one of our magazine-recorders that puts a new record on the spindle of the turntable when the other has been used up. That would run you for hours, if you'd stop it in between dictating periods." The thing was arranged and Roger, before going home, demonstrated the mechanism and was sure the old man understood its operation. Because of the threat implied in the forged note, Grover gave Potts instructions to transfer from Doctor Ryder's rooms the mechanisms he wanted to have installed for Roger's protection. With a changed switch operated only from inside the room, the former ease of operation by others, he thought, was eliminated. Roger, tired by celebration and resuming work, retired early, being sure that his switch was set, his room theoretically a sealed place. Sleep came. Rest, though was disturbed by weird dreams. Sometimes, he knew, dreams had outward causes stimulating them, as happens if a draft on exposed limbs makes one dream of riding on a sled and falling into a snow bank in howling wind. His dream of a burglar, as he awakened and looked rather fearfully around, made him grin, though. That room had been sealed by no one other than himself! But a low, humming whine made him certain that machinery was in operation--the hum of the recorder motor. He located it. Proved it. Shutting off the device in case some jar had started it, he went to test his door. But he recalled that the motor still ran. To his dismay, the door was not merely unsealed. It stood ajar. Suddenly, startlingly, from behind him, his table radio spoke, in a thin, strained, bizarre cry. "Fire!" and he heard, faintly, the crackle of flames. Then an uncanny silence, dreadful by contrast, came. He spied around the hall. It, too, was silent. He tiptoed down to the library, telephoned the laboratory, and got no reply. Once again--something was wrong--in two places! He must go to that laboratory. Grover should have answered--or Tip--or Astrovox! Chapter 21 TRAGEDY! Half way to the laboratory, Roger pulled up in his stride, half ready to laugh at his stupidity. A joke? Of course. Potts, on Grover's instructions, had made the room installation. To "get back" at his chum for the suspicion about the Eye of Om, the handy man could have made that "Fire" cry on a record, could have known how to break a light beam. He, alone, could have prepared the impregnable place so that it might be entered, it seemed to Roger. A recording, he also knew, was the other end of a reproduction. To print a sound-track on a disk, one used a microphone; its diaphragm sent vibrations through a selenium cell and other apparatus until it actuated the recording diamond: to play it back, the process was reversed. The use of the diamond, instead of a smooth reproducing needle on a hardened surface, _could_ cause that high, thin, scratchy voice. "But Cousin Grover was not at home," his mind prompted, "and the door was open, and the light would not work. The lab. telephone was dead, too!" Perhaps Potts had tried a joke; but it seemed as if it had turned into a warning, a summons; because, when he reached the building, the door was not secured, no protective beam had been set; and in the main office, he smelt the sharp, acrid odor of burned powder. A gun must have been fired in there, he reasoned. By whom? For what? His mind raced to terrifying impressions. Explosion! Shot! The place was jet-dark. As he investigated he decided that odor was strongest close to the interviewing desk, pungent enough to choke him. Into the larger main room he made his way, finding the powder odor was less strong beyond the main office as he switched on lights and took broader observations. On the large desk used for interviewing visitors he saw that the framed photograph of his aunt, Grover's sister, had been knocked down, and lay on its face. An inkwell, in a pool of black on the floor beyond the desk, was shattered into large fragments, and tiny bits. He stood still, and shouted. "Tip! Tip! Potiphar Potts! Tip!" Getting no answer he raced across the chemical section to the man's small quarters. The bed had been used, its covers had been thrown back, as if in haste. No Potts, as once before, stood tied to the bedpost. The room was empty. He shouted for Astrovox, feeling a strange desire to laugh at the sound of the name when it was shouted. "Astro--_vox!_" He called for his cousin. Then, with every light going, in spite of queer terrors, Roger made a thorough search of the lower floor. That brought no result. Nothing seemed to have been moved and as far as he could tell the safe was all right and the device that now made it sink into a channel in the cellar, so that a steel plate could slide over and make it impregnable, seemed to be in working condition. Reluctantly, forcing his dragging feet, he crept upstairs. No one was in sight. The old star-gazer was gone also! Roger stood, uncertainly glancing around. Had this been tragedy? A shot? At whom? Where were the rest? Of a sudden the threat in the note became his uppermost thought. Had someone--or something!--drawn the rest away, and lured _him_ there? Roger, nervously, glanced around him. The innocent squirrels and rabbits and mice curled up in their temporary respite from the ray-baths. The machines set up earlier hummed quietly, recording, slowly moving the telescope, casting spectra of a star's light in bands of greenish-brown, yellow and indigo on a flat paper-table. Everything seemed innocent enough. But where, he mused, had the scientific star-student gone to? Where was Cousin Grover? And, above all, where was Tip, one out of all of them who ought to have been on duty, if not asleep. Roger glanced up at the clock. Not five, but two, was the hour toward which the smaller hand was dropping as the minute hand marked the quarter-of. It _had_ been "fire" that his record had screeched at him. But there was no fire here! Roger began to feel somewhat like a person flying in an airplane for the first time, seeing everything else swinging beneath him, and feeling no movement himself. It made him sickish. "Am I out of my mind?" he asked himself. "Is this a dream?" There must be some loose end of this amazing situation that he could get hold of, to reel in the story and steady his rapidly failing sense of reality. The sound-camera! It had been running perhaps, till its roll of non-flam film was done. It might tell him something. Feverishly he got pyro, acid and the sodas into the developing water. He did not stop even for distilled water but took tap fluid. He immersed the hurriedly rubber-wrapped celluloid. As it stayed the required fifteen or eighteen minutes, he went over the lab. again, finding no more than before. He took out the roll, dipped it into hypo-acid fixing solution, and impatiently watched its opaque yellowish high-lights slowly dissolve and lose the un-needed silver salts, to clear into transparency as grays and blacks became more evident. Hastily washing the film, he unreeled an end, held it up under a light, to see if the sound-track at one side carried any shadows. There was a recording! Feverishly, forgetting his terrors, he raced to the projector in the screening room. Carefully in spite of haste he threaded the wet "stock" over the sprocket, down through the film gate, over another sprocket and clipped the end to the take-up reel. He snapped on the light. At proper speed, and sorry that he must harm the wet emulsion, but eager to hear its story, he ran his find. The picture was that of the upper room, narrowed down onto the various activities of the old star-reader. The first was a take of his rabbits as they scampered about under a change of ray-lamps. Then came the brief time-exposures of tabulations, preserved thus. But nowhere, except for natural sounds, the squeak of mice when a movement of a high-frequency ray cast it upon them--the chatter of the squirrels--ordinary lab. sounds of moving feet and muttered words by the old man, did Roger hear what he sought--enlightenment. He was near the end of the reel, about to give up, when his ears sent a message that snapped his muscles into taut tension. "Hear me. I am The Voice of Doom!" He saw, in the picture, the astrologer wheel and stare. He saw him turn and run out of view. Then, with scream subsiding in moan, the Voice of Doom repeated its earlier moaning, ending in the grind and sudden cessation. The film, unnoticed, ran out of the gate, and the magazine clicked to the slap of its still revolving free end. Roger let it run on. He had discovered a strange clue! Once coming from a deserted room, and once spoken on a record that had been considered blank, and then a third time from a record that had been set to catch sound in Doctor Ryder's home, had come that same Voice of Doom, the identical moaning and grating. In reality, in the heart of Tibet, Roger had also heard that sound. And in Tibet, the rock that cut off the sound had made no noise as its counterweight allowed it to shut out the wind that made the moans as it howled across the Himalayas and up through tunnel and whistling Buddha's hollow cavities! Even as he made his startling realization, Roger heard a bell. It came from the office telephone. He dashed down the stairs, cutting out the projector as he ran by. "Hello!----" A voice came, thin with distance. "That you, Rog'?" "Yes. Tip--at the lab. Where are you?" "Hunting Grover." "Where did he go?" "To find the star-man." "And why did he leave?" "He was--took!" "Do you--does Grover--think he was--was in danger--hurt?" "We don't know. You stay there. I'll keep in touch." The connection broke off sharply. From behind him a voice addressed Roger. "Follow me--and be silent!" There stood the Lama from the Tibetan lamasery. Two others, also. Wordless, helpless, Roger moved: they closed in behind him. The night swallowed the quartet. Chapter 22 WHAT HAPPENED TO THE EYE OF OM They allowed Roger to lock up the laboratory; but he had not been permitted to re-set the rays or other protective devices. That did not concern him overmuch. Roger knew that the safe protection was a separate circuit from those he had cut out when he had unfastened the door on arriving. Besides, he told himself triumphantly, he had recalled the camera fixed in the small decorative panel over the interviewing chair, so arranged that it would photograph a short time exposure of the office and of anyone there. Used to make records of visitors on their arrival with new propositions, as well as a night protection and recorder for the office, it had been operated by Roger, with good presence of mind, when his captors had entered. Whoever came there later would be able to develop the picture he had left recorded. He had not used the continuous mechanism, but his one photograph would reveal him and the Tibetan trio. A taxi, taking them to some unknown district, was further cause for triumph. The taxi, from a nearby stand, had been used before by the laboratory people. Its driver knew him, though he gave no sign. Roger meant to act in such a way that the man, discharging his fare and being paid, would suspect something wrong, return to the laboratory, or consult the police. At a quiet, small hotel, the machine stopped. Roger, with hands clasped behind his back, made gestures; waggling his fingers to attract the taximan's notice, then touching himself and clenching his fist. "Thanks, feller," the man took his fare, and added, to show Roger he was "wise," "That science place brought me a good tip. Guess I better go back and see about more good fares there." Instead of causing a commotion as they passed the drowsy office clerk, Roger let things stand as they were, and was taken up to a quiet suite where the two guards placidly watched him while the Lama telephoned from another room. After a while, returning, the man ushered in--Grover. "How did you come here?" cried Roger. "So they got you." "But you shouldn't----" "I didn't exactly walk into a trap, Roger. The Chief of Police knows where I came in answer to a note handed me while I was trying to trace Astrovox. If I do not telephone within an hour, somebody will come to see what's what." He explained what Roger had not known (after hearing the strange events of the opened door, the screeching table radio and seeing the smoke-filled office). "I stayed to watch Astrovox make spectra-graphs of color bands," Grover explained, "sending Tip here to be on guard. An excited call seeming to come from him brought me to the house just as a note he got started him to the laboratory. We passed, not knowing. I found your safeguards apparently working, and returned. Potts was trying to reassure the star-gazer who had heard that Voice of Doom. But Tip was frightened also. We sent the astrologer to lie down on Tip's bed, while we investigated. He came back to us after a few minutes saying he was too much upset to stay there. He thought the Tibetans had involved him in some manner." Tip, it appeared, had agreed to go along to be sure the man got going and reached home safely. Tip had bidden him wait, in the chemical section, while he went to his own room to get a weapon for safety's sake. "I suppose he must have heard something or started into the office, Roger. At any rate, suddenly, we heard the shot. I was down those stairs in a bound, and beat Tip by ten feet getting in where the smoke still hung in the air." "It was strong when I got there." "But the office was empty. I told Potts to stay, and ran out. A man, strolling, had stopped. I asked if he had seen a man go out and he pointed up the street, and like most of those night-prowlers he tried to avoid the light and hid his face with his hat brim. He was fairly short and stoutish, but it wasn't Astrovox. I ran, and thought I saw the star-gazer further along; but it was not our man. I suppose Tip, worried, came to look for me. You say the wires were silent." He was stopped by the arrival of Tip who had been lured, as he had, by a note delivered by a boy; and almost on his heels came Clark and Doctor Ryder, fuming and puzzled and anxious. They were given no time to exchange words. The Lama spoke: "We want the sacred relic, the Eye of Om." "It is in the Buddha's head," Roger said earnestly, "I saw this man put it there." "He tells the truth," Clark declared. "To prove it," Roger hurried on, "the prongs work open when you press the Buddha's third left finger straight in and then back." The Lama stared. "And to furthermore prove it and make it inadmissible----" "Incontrovertible, Tip means," said Grover. "--I went back, later, to take wedges out of the lower lever, after we beat your trick tunnel, and picked up the Imitation that Rog' tells me Mister Clark throwed away. I carried it as far as Bombay, and figured it wasn't worth anything anyhow, so I left it in the waste-basket in the hotel room." The Tibetan lama stared at him sternly. "That was but an imitation. It was the one taken _out_ that I demand, from the boy who must know where it is." "But--I tell you!" Roger was earnest, "I saw Mister Clark exchange the false one. And he dropped the one taken out into his coat, and when we got out of the tunnel and closed the rock, he threw it away, saying it wasn't any use. Tip, here, found that!" The lama shook his head. "The Eye of Om is not in its socket!" A sudden thought came to Mr. Clark. With a cry of dismay he told them his startling idea. "It must be that in the excitement, meaning to exchange the imitation for the real--to put back what rightfully belonged there and protect my friend, Doctor Ryder, I must have mixed the gems, and instead of replacing the false one with the real one, I must have put the false one back, and really threw away the true Eye." "Then--I throwed it away in Bombay." The lama considered the statement made by Tip. "If any of you speak falsely," he said, slowly, "you who speak so shall hear the Voice of Doom and shall feel the Wrath of the Hand of Doom." With that threat he bade them depart. Chapter 23 THE ACID TEST "Oh, no you don't," Grover spoke for the first time during the interview, "there is a matter of a vanished scientific student of the stars, a shot prior to his disappearance, and other things." The lama turned toward his aides. Grover, as Roger and Potts sidled close, smiled. "An hour and ten minutes has elapsed since I arrived," he remarked, pleasantly, cool and slightly triumphant, "I would not be surprised--yes, there they are." The police car, sent by the Chief of Police, brought two patrolmen and as a frightened clerk ushered them in, the lama shrugged. Captor became prisoner, and with his pair of native aides, the lama was taken to the laboratory by the interested officers. There, as Grover's car discharged its crowd of former captives, Roger was able to reward the taximan who had faithfully read his signal and who was waiting with a patrolman to be assured that all was well there before going to the address the taximan had noted. "I knew this joint was lucky," the taximan chuckled, pocketing a pleasing tip, "Hope all stays well--but if it doesn't--I'll be handy." While Tip was sent to develop camera films from various devices which had been set off during the exciting developments, Roger was busy assembling the ingredients for an experiment which Grover meant to conduct, in order to learn which of the people there had held the pistol that might have harmed old Astrovox--that had certainly been fired in the office. To their surprise as they brought together the necessary chemicals and Roger got out plaster-of-Paris from his stock-room, with highly refined paraffin, the star electrician, Ellison, arrived. "What brings you here at five in the morning?" Grover stared at him with a degree of suspicion. "I have been working out theories about our queer situation," declared the electrical specialist, "I could not sleep, because Clark had told me all about his experiences with Roger in Tibet, and I was of the opinion that Roger might be in danger." "I told him how they had captured you," Clark said, as Roger recalled that they had worked together in India on power-construction, so that there was nothing to fix suspicion on them in thus having a reunion after Clark's return. "I went to your home," he told Grover. "Roger's room was open, his aunt was greatly disturbed because you were also absent." Naturally, he had come to the laboratory. While he softened the paraffin, Roger told him their adventures. "Now," Grover told the absorbed patrolmen, and a detective who had come, by Police Chief's order, from Headquarters, "here is a dodge that some police departments have tried, and it will interest you." Roger assembled on the interviewing desk his heater for a great lot of the wax, held in a crucible over the electric stove. In a large glass container he mixed, according to a formula dictated by Grover, nitric acid and other chemicals, which discretion suggests should not be mentioned here. "The purpose of this experiment," Grover said, "is to learn which hand, if any among us, held, and discharged the weapon. That seems to be the simplest way to narrow down investigation. Once we know our culprit, he must reveal where Astrovox is, what happened." The very modern experiment, the police saw, was based on the fact that the charges used in modern pistol projectiles form, during combustion, gases which leave marks on any hand discharging the bullet. Grover explained his procedure. "The gases blow back sufficiently to mark the hand," he stated. "If our test is made within five days after such an occurrence, the test will reveal it. "I will be first. Roger will take the wax, properly softened, and at a temperature around one hundred and fifteen degrees, Fahrenheit, not hot enough to scald, will pour it over and will mould it around my hand." Roger carried out the action as it was described. "The paraffin, now cooling, at a point where it is hard enough to hold its shape, is taken off." This, also, Roger carried out carefully, securing a sort of cast with the shape of the hand moulded inside it. This, as Grover talked, Roger carefully placed in the chemical solution, and they all watched in absorbed attentiveness. "If my hand has discharged any weapon or in any other way has gotten the peculiar gases of powder combustion on it, within the past five days, the acid and solution will bring up the stains as bluish discolorations on the wax." No such spots appeared. Although a tedious operation to carry out for the Tibetan trio, and then, by their own insistence, for Doctor Ryder, Clark, Tip and Roger, the results in each case held them in suspense until there was clear exoneration of all. "But Ellison hasn't submitted yet," said Tip, suddenly. "Because I have handled chemicals in my work that may come out in the reaction," Ellison frowned. Nevertheless, though he declared that his work had brought out the stains that showed as small blue spots and smears within his mould, everybody felt that he ought to know what he declared he did not--where was the star-scientist? Chapter 24 AN IMPOSSIBLE CAMERA "SHOT" Grilled by the detective and the policemen, Ellison stubbornly protested his ignorance of the whereabouts of the former astrologer. He could not establish an "alibi" further than his recent call at Grover's home which the excited sister of the laboratory head was eager to verify. Roger, finally, decided that there was one sure and final word to be said by chemistry. If, as Ellison insisted, other chemicals than actual burning gas caused the inside of the paraffin moulds to discolor, the special tests for the chemicals he might name would say if Ellison was truthful or not--a sort of chemical "Lie Detector," Roger confided to Potts as they prepared for the experiments. To their amazement, Ellison was proved honest. The tests gave a reaction for the very chemical he named. The Tibetans, of course, had to be released. They were warned, and departed. With the experiments done, the materials removed and no gain, Tip brought up the curious situation revealed by developing the office camera film and others. "Here is the picture that Roger said he had it take," Tip displayed, to the group assembled in the screening room, one "frame" of the non-flam film. There were the Three, the Tibetan group, confronting Roger as his hand, on the edge of the desk, disclosed his clever use of the "take" to leave evidence of his capture. "Now--study this out if you can!" Tip called out from behind the projector. He shifted the sprocket-turning handle to bring up the next picture. "That's the office, what you can see through the smoke," Tip declared, "and the smoke comes from behind the desk, and so of course the man standing there has got his back to the lens, and all we have got to go on is his coat and his hair." He readjusted the "framing handle" to bring the picture into even more exact alignment with the aperture plate of his projector, so that on the screen every part showed. "Now, study that! There is old Astrovox, scared looking. He is facing the big smudge of smoke from the pistol. "But what gets me," Tip finished, "is that the whole big puff of smoke is still hanging in the air, and the man facing it is just hit--or else his face is contractuated----" "Contorted," cried Roger. "Skip big words and say your say." "Or else his face is contorted by being awful sure he has been hit." He focused more sharply. "You can see him clear enough to know Astrovox didn't fire no gun. The smoke is between him and the guy with his back to us. But--just look. His hands rest both of 'em on the desk edge. That's how he hit against the button in the desk edge that snapped his picture. "Now--where is any gun?" "He couldn't have dropped it, and have gotten his hands back onto the desk before the smoke puff would have begun to shift," exclaimed a policeman. "Look." He drew out his service weapon, aimed into a corner where his bullet would show little and its mark could be wiped out with putty and paint, and fired. The smoke, with his own movements, revealed disturbances almost as it left the mouth of his weapon; and before he could drop it, the smoke shifted. More! The pistol, falling, cut a swath in the pall. "There's no gun. And no one is hiding. The smoke is in front of that man and between him and Astrovox," the detective agreed. "It's impossible," Potts exclaimed, "A camera can't take a picture of a shot and leave out the gun." "Chemicals," prompted Grover, "could make the smudge." "Then how about this?" Potts had another film spliced onto the first one. He reeled it in at regular motion picture speed, and out of the speakers came the strange and abrupt recording of a loud, sharp, detonating sound, as near to the discharge of a pistol as any of them had heard. Taken away by the ventilating system, the smoke of the police shot was out of the way, the screen was clear to all, and they saw that the camera had recorded light from the direction of the office, an abrupt flash. With it, the detonation. "Kangaroos and apes dancin' on a film where none could be," Tip summed up, baffled, "and now--a gunshot where the camera shows us there can't be any gun." Even Grover, usually calm, looked disconcerted, and yet a little bit excited. "Maybe," he declared, and turned to Roger, "but here is one more 'sound' to add to your list. And I feel sure that out of that list, either as it is, or when you complete it up to date, will come the hint that will enable me to clear up everything." Over-confidence? Roger hoped not. Chapter 25 SCORE ONE FOR THE MYSTERY WIZARD Grover stood up. His eyes were bright with some inner fire as he walked forward, turned and faced his attentive audience. "You have overlooked a number of points shown in that picture," began the laboratory Chief. "In the first place, assuming that a shot had been fired, you see that there is no inkwell on the desk and that the picture of my sister has been knocked over or has fallen over." "You mean, the shot was fired from another direction, and not by the man whose back is turned." The detective spoke. "Can you see any other explanation for the disclosed conditions?" "The inkwell was in a pool of ink on the floor when I got here," said Roger, excitedly, "and the picture of Auntie was on its face." "The shot was fired from a gun behind Astrovox," said Potts. "No," Grover corrected him, "because the smoke is closer to the other man than to Astrovox. In fact, it is up around his side of the desk." "But his hands----" "He did not fire a gun," answering the policeman, Grover clarified his deduction. "But--think! Where in that office could a man be, and not have the camera register his presence? Granting that he could lift the gun above his head and still keep it out of sight of the lens." "Can't be," cried Potts. "Can." Roger almost shouted in his interest. "He could crouch on the side of the desk _toward_ Astrovox, and shoot at the man behind the desk, and the puff of smoke would shoot out toward the man." "Yes," Grover agreed, but suddenly he jumped as his nerves reacted to a new idea. "But--wait! A gun at that angle could not discharge a bullet to smash the inkwell." They stared, and then admitted his sensible reasoning. "Back where we started," growled the detective. "It is a 'composite' picture, perhaps," said Ellison. "You know--one part taken at one time, another exposed elsewhere, or at another time." "Possible, not probable," volunteered Doctor Ryder. "In double-exposures, wouldn't the smoke be--I don't know the phrase----" "Not in register," cried Roger. "It can't be double- or triple-exposed. Everything is all together, the smoke over the desk, and the men properly distinct." "It just must be some trick picture," argued Ellison. "Did no other camera operated by some one having entered--they all ran for three minutes--did none have the shot recorded?" asked Grover, and Potts displayed films. "They all did. Some fainter." "We can test for distance, with a sort of applause-volume machine," suggested Ellison. "But, first, let us come back to Astrovox," urged Grover. "He is gone. Why? How? Did the man at the desk take him?" He turned and scanned the groups intently. "The fellow with his back turned has your shoulders, Ellison." "But not my suit." "You could change suits." "You certainly want to 'pin it on' me." "We want to find Astrovox." The electrician made a grunting sound. "I can't help, there." Grover, though, did not pursue the argument. He seemed buried in meditation. "Here is something we overlooked, too." He spoke slowly, searching for hints in his own inner processes. "Look at the smoke. The light in that office, according to the picture itself, was the overhead dome. Now, with that small actinic quality, the camera with a daylight type of film, would have recorded only in exposures amounting to at least a second. It _would_ have been possible for the man to have fired, dropped the gun. Possibly if he snatched it up and let it drop--no. The flash would have been filmed! Let's work at this! "Notice--the edge of the smoke is duller, less distinct, but the lower part of the smudge is thick and dense, as though--the smoke had been settling during the exposure." "So, where does that get us?" asked Ellison. "To this. The man at the desk is extremely clear. Astrovox is less distinct, recognizable but still a trifle hazy. We assumed it was the smoke. It isn't. It is the fact that when he heard the shot, Astrovox was just outside the doorway. He ran in, too fast to be recorded in that brief exposure that caught him just pausing. Now, that accounts for the other camera's proving that a shot was fired. "It was fired at the man behind the desk. Then Astrovox ran in, and he had to be there an appreciable fraction of time to be registered. He got in just about half-way through the exposure, and his pause imprinted his image just before the shutter closed. Now--what would have been his natural, subsequent procedure?" Frightened by the past sound of the Voice of Doom, he went on, the man had been about to leave, and was merely waiting for Potts. "He ran in, saw the source of the shot, saw the man crouched under the desk after his shot had hit the inkwell instead of his mark, the other man. He turned, and ran. But the man who had crouched would know that he had been seen, must think the old man ran for help. "He went after Astrovox--to silence him!" The auditors, spellbound by his train of reasoning, had literally hung in suspense. "The man evidently had a gun," Grover went ahead with his thought, speaking slowly. "He took only a fraction of time to leap up and pursue. He would not have let Astrovox get far. "Let us search the areaways nearby," he concluded, seriously. They scattered, the police officers and the detective organizing the search. It was "score one" for the Mystery Wizard. Sound had been his deductions, as events showed. Only in one point had he been mistaken. The old astrologer had not been shot. His limp body, brought in from its place within an old packing case across the street, showed that not the muzzle had been used to make of him a target. The butt of the weapon had left its mark. "Adrenalin--we may bring him back!" shouted Doctor Ryder. Potts raced for the nearest drug-store, while the police called an ambulance. "Let me work with him," pleaded Doctor Ryder. But Tip did not secure the heart stimulant, so seldom, and yet occasionally able to restore heart action after it has seemed to cease. They took him away, and Grover, stunned at his own accurate deductions, hopeful that he had reasoned so accurately in time, went too. The rest hung around the telephone. At last came word. "He will probably live!" Chapter 26 ROGER LISTS HIS CLUES During Grover's absence at the hospital, the staff began to arrive. Until the secretary should come to handle the switchboard Doctor Ryder volunteered to be monitor on calls, being extremely anxious concerning the condition of the assaulted star-reader, as were the rest. Roger, as Toby Smith with a heavy suitcase arrived, turned over the few requisitions for stock to his willing assistant. He wanted very much to fill up the list of sounds he had begun in the office before going to Tibet. "Suits me fine," Toby agreed, "I got a lot more of Doctor Ryder's what he calls compounds, that he is going to use to medicate the rats he is going to replace." The members of the staff, trained under the phlegmatic, scientific methods of Grover, took very little time to discuss conditions. The routine work of scientific research had to proceed. They made it do so. Each took up his task. Mr. Zendt, with his new investigations, and the electricians and other staff men, left the matter that had no bearing on their results in the hands of those most interested. Potts, while Roger located his "sound" list, speculated about the situation. "That Ellison come out on top in the chemistry retroactivities," he began, and when Roger had substituted "reactions," he proceeded: "But are you so sure, Rog'?" "Well, the way Grover works, I am not sure and I am not un-sure. I'm going to dig to the heart of truth. Now, with our clues, we have a lot of circumstantial evidence-clues; and we have a heap of visible clues; but I think the audible ones will tell most, just as Grover does." "Circumstantial evidence? Such as what?" "People being at certain places. Here, maybe, when something happened. And like Mister Ellison arriving just when we least expected." "Then, what about visible ones?" "The animals on a film taken in a room with no animals in it. The actions of people, if we could only read them. The picture in the office, last night, with a man's back turned, Astrovox scared, and the smoke." "The others--the vocational clues----" "Do you mean 'vocal'?" "Uh-hum. Them I know most of. But there's ol--olle--something about a factory----" "Olfactory? Clues coming from smells? I think you've got something. The powder smell, for one." "And now, how will we coagulate 'em?" He was fond of that word, erroneously used, before--but to him a discovery. "I don't know," Roger admitted, "there must be some link." He suggested that inasmuch as the man in the office shot had worn gloves, as revealed on his outspread hands, no finger prints had been left when he had inadvertently pressed the desk button. "But there might be clues on the floor, if they haven't been tracked up too much," Roger suggested. "You do some micro-photography while I revise my list." The list he located in their office file, behind the registrations he had previously looked up to find the clue, as it had seemed, that Zendt, with Australian experiences, must know about kangaroos, while Ellison--there he cropped up again! could know, from India work, about the ape they had seen in the film of the upper room. Looking over his list, in the light of what had happened, Roger was inclined to drop out the seemingly unimportant fact that the case had begun when both the fire and the protective system alarms had rung. He felt that it had no discernible connection with his mystery, being so easily accounted for by the fact that an ape and a kangaroo had evidently gamboled around in the studio, setting off alarms unwittingly. Still, half-hesitant, he left it in, but re-wrote his list, so as to put what seemed important in order, rather than try to follow the succession of historical order, as he had done before. His list, thus revised and added to, ran this way: _Sound_ _Possible Meaning_ 1. Frying-grease-like Claws of animal. Radiator valve with steam clicks and hisses and coming in. A snake, with its scales pops. rattling. A lizard, like the big Iguanas. 2. Voice of Doom. Tibetans' trick to frighten. A recording made in Tibet. 3. Voice of Doom again. On a record supposed to be new. Query: how did Tibetans know all about our stock to substitute? Query, could Ellison have done it? 4. Doctor Ryder's talk Voice was his. We thought and he admitted it with man on record was Mr. Clark he was talking with. Query, with No. 3. we thought it was to conceal identity that Mr. Clark wrote; wonder if it was not a talk with him in room, if he telephoned instead? Is Mr. Clark completely cleared: he is a jeweler. 5. Clicks in headset. Could be so many electrical switch noises or relays, but why was it so close to hearing Voice of Doom? 6. Drip or click in Was just before safe was opened, but was it dark. the combination being worked by expert who could tell by sound when tumblers fell right? Does that make me think of Clark, a jeweler? Not Tibetans as we had thought from circumstances. Is Ellison able to work a combination "by ear"? 7. Thump or thud sound. Seemed to come in corner of room upstairs just before I took the film that produced the animal 'ghosts' after we had heard Voice of Doom from up there. I wonder how important it really is, or if it was just plaster or a film in a can? 8. A sort of thump on We thought he had been knocked down by a blow Record when Dr. Ryder with recorder operating. But it turned out vanished. he had gone away with Clark. Or so Clark said. Has Clark got some hold over Doctor Ryder that made him go after a telephone summons? Was that thump the telephone taken off hook? Not likely as it would be a click like what I heard in headset. Do these tell me anything? 9. The cry of fire and No fire, and no reason for cry. Wait! It was crackle of flame on like what old Astrovox said when we were unused record in my collecting old papers in upper room? Is it room. possible anybody made a record of it? But Potts was the only one who was fixing protection machines in my room. Yes, and Potts says he threw away what turns out to be the real Eye of Om. Oh, it can't be. 10. Both alarms went Can't mean anything but I feel like keeping off when mystery it on record. began. 11. Shot recorded in A brain-teaser. It was an explosive sound, the lab films at same that synchronized with flash in film: and time as flash. there was the smell of burned powder. How does it fit? Did Clark or Ellison do it to try to shoot the man at the desk? Or did either one do it at the other? 12. The Tibetan talked It _is_ 'sound' and might have some clue, he English. used English in a Tibet monastery, and in America again. 13. The whistle and Wind howling as it blew hard or gentle in moan in Tibet same as tunnel and Buddha-whistle. But no 'grind' on recordings. in Tibet. 14. Grind as if rocks Missing in real Tibet sound, as rock was on records, after counter-weighted and moved silently open Voice of Doom. and shut. Seems important, because it was on record probably made in Tibet and brought here by--Tibet lama? Clark? Ellison? Zendt? 15. Voice of Doom heard Was it record, same as others? Or what? I by Astrovox. must ask when he recovers if it had grind at end of moan. Those, as far as he could recall, were his sound-clues. Chapter 27 A "THERMAL" TRICK With every meaning that he tried to attach to his listings, Roger found himself growing more confused. He had only imaginative evidence against any of the names he had inserted in his diary-like notations. As he scanned his list Roger saw that he had done less interpreting than speculating; but he saw no way to make interpretation of the listings get him anywhere. He filed it with his former list, and went to his routine, so that Toby could go to dinner. The rest of the day was without apparent development. Toby, leaving the suitcase, at closing time, went home. The others did the same. Roger and Tip remained until last. "Well, Grover has stayed close to Doctor Ryder's patient," Tip mused, aloud. "That is, the patient Doctor Ryder just missed getting, because I told the druggists I wanted 'aggrenalin' and they said they never heard of nothing like it. If I'd of got the right name, he'd of saved Astrovox 'stead of the internes doing it." "I talked over the wire with my cousin," responded Roger. "Just make an extra check on everything for safety's sake, and he says for us to _stay away_ from here, tonight, no matter what we hear. You are to go to a hotel to sleep. And he says you must." "What's going to happen here?" "I wish I guessed," Roger retorted, "but I don't seem able to do even that. With all the clues on my list or somewhere in the films and so on, I just see new developments, and they are worse than before, and confuse me." "What say we go to one of those spirit mediators." "A medium? A fortune teller?" "She might coagulate our ideas." "Curdle them? She probably would." "It means to make 'em set--hang together." Roger chuckled and refused. He wanted to work out every circuit, trace every wire, be certain that when he locked up, nothing could get in or out of that research laboratory without leaving a record and if anything happened then--well--he'd have to look to Tip about it! Potts said good-night, and went away as instructed. At home, telling with some reserves his experiences of the night before, to his aunt, Roger felt a constant tugging of desire to go and see if all was right. Grover's orders to stay away were, he felt, a magnet drawing, tugging, pulling him toward the forbidden place. What danger, he wondered, might lurk in just a visit? Still, he obeyed, against every dragging urge. Toby Smith telephoned about nine o'clock. "Say, can we get into that lab?" "Why, Toby?" "I clean forgot to put away Doctor Ryder's compounds. I put down his suitcase, and got busy with Mr. Zendt who wanted a heap of chemicals, and it slipped my mind." "Orders are not to go there at night," Roger told him. "Well--but he said lock 'em in the safety cabinet, against fire. I forgot. Well----" "But there won't be any fire." "But--lookit, Roger--you didn't notice, maybe----" "That you had marked on a paper a list of words? I did. Fireworks. Pyrotechnics. Lycopodium." "Well--I mixed some--an' left 'em in a big tray till tomorrow." Roger gasped, at his end of the connection. Suppose a gas in the atmosphere reacted with some exposed ingredient? All at once, though, a person so far totally unsuspected began to assume importance. This Toby Smith! He had originally sold, for a camera, a gem supposed to have been both sacred and invaluable. He had been to Tibet before, Doctor Ryder had mentioned. (He could have known the value of that gem). Besides, here he was, at a time when Grover had explicitly forbidden Roger, for some hidden reason, against going near the lab. And he was insisting on his disobedience of orders by implying dire happenings! Roger hesitated. Why was it important for him to be lured to the laboratory? Had Clark not explained to the Tibetans about the blunder through which the real jewel, jettisoned by Clark, picked up by Potts, had been lost, they might want to lure him, to bring some idea of revenge to pass. Why should Toby want to do that? Perhaps, Roger speculated, the youth wanted to get him there and then by use of force open the safe or some other thing. The value of their own laboratory formulae and data was not less, to them, than a jewel such as the Eye of Aum. "Against orders!" Roger, his decision made, started to hang up. "You'd let that stuff explode, maybe----" "Listen, Toby. I obey the Boss. Besides, don't worry. We have a positive-action, fire smothering gas in drums, and a thermostat that operates a relay, much like those on heating equipment, at a rise of eight degrees from the normal shown by another thermometer outside the lab. The gas smothers any fire. Chemicals, even." "That's good. Then I needn't worry." "You needn't worry, Toby." Hanging up, Roger waited for a further effort. When it came--if it _was_ a new attempt!--its form was startling. The inter-connecting fire alarm in the library of his home rang. Roger considered for a moment. Of course, the gas should cover every possible danger, save everything. Even against the delicate electric adjustments and the unreplaceable devices, the gas would work without harming them as water might do. The thought brought another. "Water!" The firemen would respond to the alarm, sent out over the telephone, to Headquarters, automatically. Water would ruin the delicate armatures, coils, etc. And how could the alarm go off by human means when he had made so certain that no one could enter? He decided to try to get Grover at the hospital where he waited for any word, or murmur, raving or otherwise, from the unconscious astrologer. Grover was not available, they told him. He had gone out to get a late repast. Grover would not be available for an hour. Roger could not see the laboratory electrical apparatus ruined. The order to stay away had not taken this development into account. He got a taxi and was hurried to the vicinity of the lab. Already he heard the screech of sirens, as at the start of the queer chain of contradictions, impossibilities and misfits. This time, though, a weird orange-reddish glow came up into the cloudy sky from above their skylight! As Roger leaped out, flinging the taximan a dollar, the glow was quashed as if by magic. The system of protection had worked. He stopped the breaking of the door, as before, but this time with no need for argument. The X-Ray and fluoroscope were not going as they had been that former time. Hastily Roger located the Captain of the first company to have arrived: he knew that the one so scoring a beat was in charge, stayed till last, was responsible. It was "his fire." Rapidly he told as much as was necessary to convince the man that no further damage could possibly ensue, but he found the man hard to convince. "But I declare," Roger insisted, "the lycopodium and stuff that you saw blazing up through the skylight was just fireworks compounds, made up--I begin to think--for just that use. It made a grand glow, but probably blazed only in a tray. The room it was in is fireproof. Our film is all non-flam, in sealed or airtight cans. Our chemicals are in airtight containers." He added that his check of the tell-tale, on the brief entry he had made, disclosed no entrances by others. Such was impossible. "Then how was the stuff ignited? Spontaneous combustion." "I suppose some gas was left open, on purpose, that would in time penetrate to the chemicals in the mixture. But the heat of that little couple of pounds of powder burning ten minutes would not raise our fire-thermostat more than a degree, and it must go up six or eight to set off the alarm." "The alarm came in, young fellow. How?" Roger took him across to a drug store. In its window, against the wall, a huge advertising thermometer registered Fahrenheit degrees and stood at sixty-four. He hurried the man back, showed him the small interconnected thermometer for registering air temperature, against which the other inside one reacted. This one stood at fifty-five. "Somebody wanted the alarm set off to lure me here--simple trick. Only had to hold ice on this one till it dropped eight degrees _below_ the other and then the other would be eight above it and off went the alarm." Fire, an alarm adjusted for heat, set off by ice! Toby? Who else? Chapter 28 THE FUSE From the pay station in the drug store Roger got the hospital and was connected with Grover. "Is Astrovox all right? Did he say anything?" "He will probably recover, Roger, but he won't talk for many days, perhaps for weeks." Rapidly, concisely, Roger outlined the situation. "But I told you----" "I am not in the lab. I went right away from there, making sure all the safety things were still on, before the firemen had pulled away." "Don't go back, no matter what. And--Roger--be sure your room is protected fully before you go to bed." "What's the matter? Do you know?--who is it?" "I don't know who it is, but some desperate person has determined to protect him or herself by any necessary means." "The Tibetans?" "I think not, Roger." It was some person or group recognized by Astrovox. That recognition had led to the blow he was suffering from. "Fortunately, it was not fatal," Grover continued, "and I stayed here less to hear him, for I knew that would not be probable. I was here to protect him if anyone, knowing he lived, tried more desperate methods still." "You can't stay day and night." "No," answered Grover. "Potts is on his way here now. I will be home in an hour or a little more than an hour." Roger asked one more question. "Why would they want to lure me to the lab?" "No other way to get in." "But they did get in, Grover. The lyco----" "Probably touched off with a long pole, from the skylight. They could break the glass, insert a long pole, like the one we use to shift the ventilators. To draw firemen who would smash in--or set off an alarm that would bring you, especially after the preparation by Toby." "Then he----" "Probably someone either paid him well, or else, as I think is more likely, he really had left the powder there. Some one knew it." "Why should I be bothered?" Grover's theory was that through his reputation as the Ear Detective, or else because of some film or other data, the suspected miscreant feared him as he had feared Astrovox. The conversation ended and Roger, finding his old friend, the taxi driver, on his night station, used his car. At home he made certain that the devices, moved from Doctor Ryder's residence, which no longer seemed threatened, because the absence of the Eye of Om had been explained to the Tibetans, all worked. He shifted the recording needle a dozen turns of the threaded arm that made it follow a spiral path. The call of "fire" and the crackling noises occupied only the start of the disk. He set the recorder to fall in place further over toward the center. Switching on the electrically charged locks, he kept his desk lamp burning while he retired. Just as he was about to turn it out, the light died. Thinking that the bulb had been used up, he tried another light, just as a precaution, recalled to mind by the doctor's experience. That light was unresponsive. At once Roger raced to the door into the hall. With no current the lock, with his key inside, turned readily. Intuition told him what had happened here, as in the other instance. The cellar fuse box had been opened and a fuse had been removed. That prevented current from entering the circuits, and even the alarm was silent, although he knew that cutting off the current served as well as any other way to start the recorder disk and the camera. He cut them off hurriedly. "I'll want them, maybe, a little later," he told himself. "Whoever did this will have to come up two flights of stairs. It will give me just time to re-adjust them to go on again, if I want. And I hope he or she or it left the fuse by the box." He had a plan. A trap, made useless to protect him, could be made useful to hold someone else! Slipping into his bathroom, with his clothes carefully tucked under his arm, Roger unlocked the door into Grover's adjoining room. He went in there stealthily. Then, waiting, he listened. His one danger lay in the chance that the miscreant might come by way of Grover's room, if it was known to be empty. As he heard someone working a jimmy or other springing implement on his door, very quietly, though, he slipped into the hall with as little noise as the hinges of the door allowed. It was hardly likely that the slight squeaks were audible down the hall. He saw a man, bent low, his back fortunately turned that way, as he tried to snap open the lock without much noise, perhaps trusting that Roger slept soundly and would not awaken. Like a wraith slipping without sound along a haunted hallway, Roger got to the stairway. Its noise must be risked. He trod close to the wall side, stepping two lifts down to avoid a known faulty stair. It required nice psychological deduction to enable him to use his trap, if the fuse was available. The marauder, or worse, must be in the room, and as Roger hoped, he would probably have shut the door to muffle any commotion from getting to other possibly occupied rooms. Once in, the person would see he was not in bed, and had not been, and would either take a moment to discover if he hid, or would pause to consider; he must have been watching, must have seen Roger arrive. The fuse, when he snapped on a cellar bulb in the garage, was on a ledge under the switch box. Was it too soon, Roger wondered, to screw it into the tiny receptacle? He must not wait too long. His absence once assured, suspicion and fear would drive out the one who was now _his_ quarry. He must risk it at once. He screwed home the small 15-ampere fuse. With hopeful heart and padding feet he ran up the cellar steps, up the next flight, and paused to take observations. All was quiet. Had his trap sprung? He could tell by finding a rubber glove among Grover's things, with which to try the knob he had so recently turned with ease into his bathroom. He got the insulating glove from among some old laboratory togs, too big for him but satisfactory for his need. With care he turned the knob. The door did not yield. The system was on. A difficulty came into mind. To see if he had a captive he must release the heavy charge, by use of a small cable-key that broke the circuit. If his presumable evil-wisher was caught, he might get out before Roger could re-set the system. He listened. There was not an audible sound, coming through the door. Chapter 29 A SURPRISING CAPTURE A sound in the lower hall made Roger turn. To his delight, Grover came in. Quickly the younger cousin set out the situation. "Go down and draw the fuse again," Grover suggested. "Queer that I did not think of that simple way to nullify all our protection. It explains how the safe was so easily opened, as well as Doctor Ryder's situation. When you are ready, pull only the ten ampere fuse in the equalizer of the circuit marked number four." Roger knew that the switch and fuse box held different fuses for various parts of the home, with two heavier fuses set into the main feed from the street. Grover's idea was, he saw, to eliminate the front portion of the house including his room, while the light in the rear of the hall, and his aunt's quarters, would be left on. In that way, with a front hall light going, Grover could tell when the fuse was out and have light enough in the hall to work by. As soon as he had performed his task he ran up the steps, to find Grover, extremely surprised, facing, in the hall, the last man they had suspected of interest in the matter. The assistant electrical engineer, Mr. Millman, stood there. "A lame explanation," Grover was saying as Roger arrived. "To you, maybe. To me it seems reasonable that I would have hit on the method somebody used to get to the safe and I think it is perfectly logical that I should test out my theory that Roger had been playing all those tricks in the laboratory." "What tricks?" Roger demanded. "This one, if you want a sample." Millman walked over to the recording device, exchanged from his pocket a reproducer, made a quick wire connection to Roger's compact table radio, as Roger had had the connection when the recorder had roughly re-played the formerly recorded cry and crackles. "I was making a recording of motor sparking, and just as I set our lab. machine going, I realized that the diamond was cutting a sound record, not just running smoothly. You can tell if you are watching closely, as I was. We cut out the record, took it off, and I told Ellison and Zendt to say nothing. I began to suspect that Roger, who was up with Astrovox, was having fun at our expense." He set the machine going and the needle, automatically dropping onto the groove just beyond the cuttings, as Roger had set it, had to be lifted back. Then Grover heard, as had Roger before, the cry, "Fire" and the rattling, crackling as if flames ate dry wood or paper. "Now if that was recorded, it had to come from somewhere. We had not started the sparking motor." Millman was earnest. "And I knew that Roger was up there. Later, unable to find this record, at the laboratory, I reasoned that it must be that Roger had brought it to his home. Evidently, I thought, he wanted to hide it. I decided to make sure. Being an electrician, I thought, at once, how to get in by pulling a fuse, not needing to cut wires or put the safety devices out of commission permanently." "What do you think, Roger?" Grover turned to his younger cousin, "Does it strike you as convincing?" "Maybe he might feel that way." "But--with some desperate person abroad----" "Do I look desperate?" Millman laughed. He was tallish, and a most serious mannered, quiet, earnest person. "What motive could _I_ have for wanting to hurt Roger?" "You can best answer that," Grover said quietly. "I simply wanted to justify my belief that Roger was behind all the spooky goings-on; the animals on the films, and so on." He nodded to show his satisfaction. "I think I have proved it." "Did Potts put this record here?" demanded Grover, and Roger saw that he was thinking fast. Hating to add still one more count against the handy man who had only his own word to support his declaration that he had flung away a supposably priceless Eye of Om when Clark had made his blunder in the temple, and Potts had found the discarded gem, Roger nodded. "And how was the recording made? Do you know?" Again Roger nodded. Grover frowned. "How?" "I was helping Astrovox carry away packing papers; and he mentioned that Mars, the planet, ruled fire. That word, and the crackle of the paper bunched up in our arms, would make that sound." "Was there an open microphone near you?" Then Roger started. "No." "Then--how?----" "If we could go to the lab." Roger had an inspiration, "I could show you." It would keep till morning, Grover decided; and dismissing Millman with a warning that his actions were at least not beyond suspicion, Grover set the cable-switch on, and prepared to sleep with Roger. During the balance of the night their rest was undisturbed. As soon as they reached the laboratory, Roger took Grover to the recording machine. "You will think I did this, because I know so much about it," the youthful radio and sound expert said, "but it is just putting a meaning behind certain sounds on my list, and adding the natural explanation." His reasoning proved to have been correct. A strange voice had come unexplainably from an upper room having no occupant: Roger bent, examining the mechanism under the recording turntable. He investigated the contacts whereby the electrical impulses sent from the small "mike" at the sparking motor, through the selenium cell, got into the amplifying transformer-coil to be increased enough to operate the recording diamond attaching to a special diaphragm over the disk on the turntable. "A wire had been soldered on, here--see," he pointed. "Somebody had a wire that didn't need to be there. Now, if I just wind this end of a bit of wire around that contact, to replace the missing one--" he made the temporary connection, "and lead it down to one or the other side of the floor outlet, and there attach it even loosely around one prong of the little plug-in that furnishes current for the motor of our recorder, we may discover where the speaker upstairs is located." Hastily he made a temporary splice onto the plug prong. Grover went up the steps, pausing as Roger put a commercial test-record in place, switched on the motor and set the reproducing needle on the groove. Immediately, from upstairs, there came the recording, in a booming, hollow distortion, natural to the poor connection and the device they had to locate above. Grover, walking over to the corner from which came the sound, gave a surprised call for his cousin who shut off the record and ran to the disclosure he was sure he would find. His guess was right. There, laid practically flat on one of the empty cabinet shelves, with its small speaker-unit set into a cutout spot of the shelves, and concealed by the thick wood it was let into, was a good sized slab of thin wood. The wires to the small operating battery concealed in a non-flam film can, and from that running to a wall outlet that connected the room devices with the main source of current, they traced. A recording had been made, downstairs, of voices in the upper room. To all appearances there was no microphone up there to have conveyed the voice and paper-rattle. Apparently there was no loud speaker up there to have broadcast the Voice of Doom so bafflingly. "You say to dig past appearances," Roger reminded his cousin, "and while they can be falsified, the truth never changes. Well, if it 'appears' that there is no mike, and that there is no speaker, we know we heard the Voice of Doom, and we know we heard the recording made by Astrovox, upstairs, on a record, downstairs." "There is, naturally, some connecting wire. But--it does not show. You know more about radio than I, Roger. Have you located it?" "Well, when we used to build experimental sets, before commercial radios got to be common and reasonable in price, I used to try to record my own voice, so I could play it back. I used the same sort of radio hookup for that, I think, that is used in making commercial phonograph records--only, I didn't have a carbon mike, so I tried reversing the function of the speaker I had. It was a Balsa-wood one, that I assembled from a small vibrator-unit, and a flat slab of thin Balsa-wood." "Used the speaker as a microphone or telephone receiver would be used today." "Right, Grover. And, another thing I remember from my experiments. There was a device that was supposed to use the house electric wiring as an antenna--an aerial. If you put a special plug, with only _one_ prong instead of two the way regular electric contacts are made, in a wall outlet, the circuit of the house current was not carried at all, and the single contact went to the aerial binding-post of my set, and made the whole house wiring act like an antenna. There was a terrible line-hum. It wasn't practical. But I think----" "As long as only one 'side' of the house current is tapped," Roger told his cousin and Chief, "and the part it connects with is not grounded, it will act like an antenna--or, in this hookup, it makes any of our outlets a conductor between whatever is plugged into it and the Balsa-wood speaker." "Besides Ellison and Millman, both electricians," Grover mused out loud, "Potts would know, at least from observation, a lot of electrical 'stunts'. This one, possibly. And he knows how to record; and all about microphones, speakers and other apparatus that he has to adjust in his regular laboratory duties." Another count against Potts, Roger thought--at least by implication in the evidence. But, then again, it also pointed to Ellison or Millman, maybe both. Toby arrived. As with Roger he viewed the cremated powders, and the melted metal tray on a scorched table of fireproofed wood under a zinc sheathing, where his "pyrotechnics" had burned, Roger had to admit to himself that the youth's manner and expression indicated sincere shame that he had experimented and had left his combustibles exposed. But, then, the call had come, last night, so close ahead of the fire alarm that had led to his trip to the lab. Had Toby been lurking nearby after having chilled the outside thermometer enough to cause the one on the alarm system to be higher and to set off the device? There had not been enough heat to release the gas, he made certain of that at once. Toby _might_ be one of those "dumb"-clever fellows who pretended to be ignorant to cover up something, to keep suspicion away from themselves. He decided to add Toby to his list of potentially suspectable people. Chapter 30 THE VOICELESS WARNING Since Astrovox would be away for a good while and his experiments could hardly be picked up by anyone else, Roger was told to arrange a temporary home for the rabbits, squirrels and mice and rats he had been experimenting on; and a nearby pet shop agreed to house them. In assembling their cages, Roger noticed several of the mice showing symptoms of being very nearly done for. "What do you suppose is wrong?" he asked Doctor Ryder, who was clearing aside some of the absent man's apparatus in order to set up his cages again. He expected a fresh litter of white rats for his medical experiments. "There was a fire, wasn't there?" "You think the smoke overcame them, Doctor?" "Exactly, Roger." He wrote down some stimulating combinations of medicinal chemicals to try on them. The bio-chemist, Zendt, also took an interest. "Of course, if the lamps are already turned off," he said, "it is that the smoke overcame them. That little fellow is particularly bad." He indicated a tiny mouse of the sort used in the experiments, lying almost as if in a coma. Roger, with his quick sympathy, and with Toby eagerly obeying orders, improvised a makeshift "oxygen tent" and since it would be in the way in the room already crowded with the cages and plant-beds, he took the small stimulator with its tiny occupant into the dark-room where he could attend to it and watch the mouse's reaction and response while he developed some plates taken by the staff the afternoon before. The mouse, Roger saw with pleasure, gave signs of reviving. So quickly it recuperated that he put it back into a cage, but kept it near him in the dark-room while he saw, on the developing plates, slow images emerge. The pictures, photographs of crystal formations, he finished, making wet-contact prints. These he took to Mr. Zendt. Others, of the old astrologer's, he put aside to print later. They would not be needed for some time. Coming back, Roger observed that his tiny patient was apparently much better. He dissembled the oxygen apparatus, and was about to take it to his stock-room, to the section where spare apparatus was stored, when he had a visitor. Mr. Clark, his Tibetan traveling companion, the well-to-do jeweler, came in through the light-trap, with a cheerful greeting. "How are you doing?" he inquired, "and what is the latest quotation on Tibetan's, common." His stock-market joke made Roger grin. "Glad you didn't say 'Tibetan's, preferred.'" he answered. "As far as I know, they certainly are not preferred. The quotation is lower-than-minus. No sale." He was wondering what might be the object of the call. Not a visit for love he was sure. "I hear there was almost a tragedy here," the rich gem expert was getting to the point, Roger surmised. "Yes, sir." He was not going to give information. "Poor old star-gazer. He should have seen his fate coming. If his star-reading could warn him, why didn't he take care?" "I don't know. He had said something about Neptune and Saturn in opposition and Mars opposed to Uranus, with the world between the opposite planets, pulled this way and that, if I understand him. Maybe he was trying to take care of himself, but he always says we are put into this world to have certain experiences. We cannot escape them, and what the stars' forces did to influence our cells in brain and body at birth, he thinks, indicates what sort of experiences we will have." Roger, seldom over-talkative, was willing to expand this idea. Not that he wholly grasped what it meant. Nor was he "sold" on the star philosophy. But it diverted Mr. Clark from whatever plan he had come there to try, Roger thought; and if he was right about it, Clark would come back to his subject and would thus show Roger what it was. "Astrovox often said," he hurried on with the topic, "we cannot avoid our Destiny, escape experiences. But we have what he called Free Will to decide how we will meet them." "A very sound philosophy, Roger. But----" "Now he's going to give himself away," decided Roger. "But--where have you put The Eye of Om?" Roger, petrified by amazement, could only stare, in the dim, ruby dark-room light. "I?----" "Yes. Eye of Om. You really took it, of course." "Mr. Clark!" Roger drew himself to his full height in sudden anger at the challenge, the accusation. "Well, how else could it have happened? You know, for you saw, when the prongs in the Buddha's forehead socket were loosened, I took out the old gem and put in a new one--the one we had brought. And when you sent Potts back, do you imagine I am idiot enough to believe that _he_ knew one stone from another, or that he found the one I chucked away into a regular abyss, there in the Himalayas?" He scowled. "You went there. You saw the real stone put in. You sent Potts to--shall I say the real word? No--to bring it--that's close and not quite so evil-sounding as the fact. Anyway, Roger, do you think we don't how loyal Potts is to you? He would tell any sort of story, just to protect you." "Say, you go and tell Grover that." Roger was boiling. Clark, scanning his working face, calmly chuckled. "Your films will be overdone, or whatever happens if you forget them." Roger, reminded, hastily extracted from trays the plates of an experiment with chemical diffusion, and got them into hypo. "I shan't bother Grover. We discussed it and he suggested coming to you. As long as this way doesn't elicit the information, perhaps there will be other methods. You know what taking the gem means to those Tibetans?" Roger, fuming, smarting under the unjust accusation, refused to reply. Turning on his heel, Mr. Clark left. Roger washed his negatives, made his prints. To his surprise his pet, the tiny mouse, began to run about, to show unmistakable signs of animation--or was it of excitement? Roger studied him. The tiny animal was racing around its cage. Memory of the fact that such mice on submarines indicated the presence of leaks from battery or engine of undetected gases such as sulphuric acid gas came. He wondered if his dark-room held such a menace to respiration. He decided to take the mouse to the outer air and observe its reaction. To his dismay, the inner door of the light trap did not respond. He was wedged or otherwise fastened in. And the mouse was certainly exhibiting signs of uneasiness. Chapter 31 THE HIDDEN MENACE Instead of shouting, beating on the door and otherwise wasting energy and using up the available oxygen of the room, Roger paused, taking only the precaution of mounting on a high developing table, to avoid any floor accumulation of poisonous fumes. Such mice, he remembered, could detect a dangerous fume long before human nostrils caught the odor; and this made them life-savers on submarines. They gave the crews time to trace gas fumes and suppress or nullify their effect. "Now, there isn't any gas I know of in what I am using," Roger spoke, under his breath, to his tiny companion, just as most people will discuss an emergency with a dog or cat. Fumes of such chemicals as he might use for "reducing" and "intensifying" improperly exposed negatives gave off offensive odors in certain mixtures; but he had mixed none. Hypo was not dangerous: and the ventilating system should have sucked away any fumes of whatever sort, he knew. Nevertheless, the animal grew still more excited. Roger lighted the white, glaring dome light, ignoring possible ruining of the developing plates in his trays. He knew every content of that room. Nothing was out of place except what he had been using. There was the extra paraphernalia of the oxygen apparatus. Nothing else was visible. It came to him that no odor or fume could be liberated that would cause such frenzy in the little white savior unless it was introduced from an outside source. He would find out. He went to the intake of the ventilator, and with litmus paper, and other handy agents, he made several tests, keeping his nose and lips within the tight folds of a handkerchief as he did it. The litmus did not at once indicate anything. But when he thought of what he had sometimes read of closed garages, with car engines running, in which people had been overcome by exhaust fumes such as carbon monoxide, he made a hasty test, with what he had available, and was very sure that the gas or one of that nature, was in the air. A tiny animal might be going to save his life. Roger knew his next move. He would shut the ventilator, prevent the inflow of any more fumes, leaving the exhaust openings to suck clear the accumulation which would lie near the floor. He got his oxygen equipment, and climbing onto the highest table, he made an improvised airman's outfit such as they used when ascending beyond the human range of breathable air. He used his oxygen and mixed it with air inhaled only through a handkerchief strainer. He thought in this way he could hold out, and then whoever had come so close to being in line for the electric chair----. He watched the mouse for signs. After a few minutes the animal, at his level, quieted. Roger, allowing still more time, finally laid aside his protective "gas mask" arrangement, and quietly tried the door. It had been unwedged. He did not emerge, however, but went into a corner to wait. Whoever might open that door, he thought---- A criminal would haunt the scene, to see the effect of his plan. Would it, he wondered, be Clark? He had threatened. Or--Toby? Or Millman? Of course not the Tibetans. They were not chemists: they were priests. He grew tense, watchful. The outer light-trap door was being opened. Chapter 32 SCIENCE FIGHTS CRAFT Watching, Roger saw and recognized the man who entered. The bio-chemist, Zendt, came in with a film magazine of exposed celluloid in one hand. "How are my diffusion shots coming along?" "In the hypo." Roger watched narrowly. Zendt was either a master of facial control or he was one of those "innocent bystanders" who manage to intrude when some crucial point of a drama is about to be played. "Please develop this run from the speed camera. Ellison and Millman have caught the torque of their erratic motor on film. Sixteen exposures to a foot--a million to the minute. Shooting time, one half minute. Does that tell you the size of reel to wind it on?" Roger, making mental computation with one side of his mind as he studied the situation with the other, nodded. He would put the ceiling light out, but he would not satisfy Zendt by staying there. Perhaps the man came prepared to hold him at his dark-room work in case he had not yet been sufficiently dosed. "Bring you prints soon," he told Zendt. "I'll get this into a developing tank." He risked a question. "Is anybody in the cellar? The ventilator seems to be choked. No air comes in. It's--stuffy." "Maybe. Millman was down, earlier. Potts hasn't come. Grover has gone out." To let Potts get sleep, to stand guard over Astrovox, Roger decided. "I'll telephone down and see--oh, look. It was shut off." Clever actor or innocent intruder, Zendt betrayed neither interest nor disappointment. He simply nodded and went out. Roger considered his position. He reasoned: if Zendt was blameless, some one else was watching. From seeing Zendt emerge the unknown would be sure that Roger was still all right. But if he left, all possibility of detecting who was the culprit might be gone. Still, he had no chemicals in assortments that would enable him to detect the possible introduction of some fume through a hole in the walls, or some other move. Besides, he was open to bodily attack. He must not be there. No one must see him leave. He remembered that there were chemicals that he would need, and inasmuch as he was known to be all right, he could easily get them. He emerged, seeing Doctor Ryder busy with his arrival of white rats, with Toby helping him put them into the glass pen through the trapdoor in the top that prevented them from escaping. "Got to force-up some underexposed negatives," he remarked as he passed them. To the stock-room he went, and procured the ingredients he needed; but not for an intensifier for under-exposed film! Returning, he noticed Zendt, watching the rats also. Once more in the dark-room Roger proceeded methodically and carefully to produce a very businesslike detonating torpedo with crystals of gritty hard iron oxide-rust! to take the place of the gravel usually packed in a commercial torpedo of the sort formerly sold for exploding by contact with the sidewalk. The other ingredients he mixed with care as to method, as well as formula, knowing that certain chemicals must be combined in a certain sequence. Wrapped in a fairly good paper taken from a packet of printing paper, he had his torpedo ready at last. There was no window from which to fling it, but he knew that by putting a chair on the developing table by the wall, he could get his hands up to the small outlet around the exhaust fan. The old equipment, discontinued since the laboratory had put in air-conditioning, led to the open air. He got to the position carefully, took his torpedo, and adjusting the small exhaust fan so that its blades would interfere the least with an open passage for the missile, he took his chance, against striking the blades, flinging with a quick jerk of his wrist that sent the detonator straight through past the fan. Hurriedly he climbed down and got the chair back in place as he heard, muffled by the drop, a sharp explosion on the pavement in front of the laboratory. He was certain that the noise would draw everybody. In the space between the outer and the inner light door he listened. Doctor Ryder and Toby went with the rest. The way must be free. Roger, emerging, saw that his guess had been correct. There, poked up through the skylight coaming, was the long, and large-girth telescope of Astrovox. To an athletic youth, with agility and endurance, to climb the steadily enlarging, inclined barrel was no hard task. Once at the top he got over onto the roof with skilful swings of his body and flexing muscles drawing him safely over the coaming. Then he watched, unseen from below, careful to be on the side facing the sun so as not to let his shadow reveal his position. There he watched for an hour as Doctor Ryder and Toby returned, and others came to the stock-room, but went away to await his arrival from the dark-room. Their wants must not be urgent. The vigil was fruitless, though. No one entered the dark-room, barely visible in his quick glances. A new idea came. He went up the rainspout of the adjoining roof, using knees for grip and hands to pull him up from one bracing ring to another. Down the adjoining fire escape he went, to the top floor of the candy factory where, to the surprised girls, he whispered, pretending to be mischievous, "Playing a trick on the folks next door." They all knew him, from seeing him going to and from work. He accepted some candy, and went down and out onto the street. He saw no one watching. The brown mark of the torpedo detonation was still on the pavement. He slipped into the laboratory cellar, by way of its ash-lift, unobserved as far as he could tell. To the air-conditioning system he made his way, trying to see if any of its outlets, especially one to the dark-room section, had been removed or tampered with. He saw some signs that a pipe wrench had ground rough bright spots on the piping, and smiled. His idea had been right as to where the gas had been sent up. A survey among old trash awaiting the attention of Potts revealed a large, empty tank. Some one must have charged it--whether by purchasing the materials or by injecting the exhaust from a car he never found out. There, though, was his evidence. He left it as it was. Grover had been right. Some person or group, with intentions far more vicious than had been in evidence among the Tibetans, had marked him. Why? What did he know? Not the place of the lost Eye of Om. For that they would want to take him prisoner, to question him. This attack had been because someone was sure that he knew more than he did. Could he find out what he was supposed to know? To try was Roger's immediate intention. Chapter 33 A NEW SUSPICION It was Roger's plan to consult his list of "sound" evidence and try to make it tell him whatever secret must be hidden there. No other plan seemed so likely to be fruitful. If he was supposed to be in the dark-room, his presence in the office must show to some guilty person that Roger was equally alert and crafty. He wanted to "start something" in the open. Underground methods, secret attempts to do away with him, were hateful to open-natured, frank Roger. Strolling up from the cellar, he watched the effect of his arrival from that unexpected quarter. Mr. Millman, discovering him, looked up with a start. "Hey! Thought you were developing the stuff Zendt took up." Zendt--Millman. Roger connected the two mentally. "Those speed pictures are important." Mr. Ellison scowled, and Roger began to wonder whether his anger was genuine or if he, himself, was giving too much importance to a mere annoyance. "I was just testing my new 'cloak of invisibility,'" Roger put on a careless manner. He would give _them_ something to puzzle about. "Science is just the reality that used to be fairy stories," he said, with a grin. "Pegasus, the flying horse, was just another way of prophesying airplanes. And if a magician could wave a wand and turn a beast into a Prince, doesn't chemistry transmute base elements into wonderful, modern products? I got an idea that the cloak or helmet of invisibility, like the Helmet in Wagner's opera that I heard on the radio, is just the prophecy of some Omega-ray, that makes things transparent and invisible without hurting them. It works, too. Did you see me go out?" "No," Mr. Millman snapped out the word, adding: "But we _will_ see you go out--to the observation ward of the psychopathic division in some hospital if you waste any more time with this crazy talk." Roger, thinking quickly, decided that he was hearing a threat. Millman was not joking. If an astrologer, coming into the office, had recognized the man, either facing him or hidden under the desk, and for that knowledge had come near to being "sent West," then it would not be put past such desperate people to believe they would deliberately put him into the ward where supposedly insane people are kept, while doctors studied their mentality. That, he reflected swiftly, would effectively get him out of the way; and it would discredit his ideas. "I was only joking. What's the matter with everybody? Snap me up because I chased out past you to see what the shooting was for." "Well, get back to your work. Potts isn't here. It's up to you to keep things going till the Chief says differently." Roger looked defiant. He meant to see how far the man--or the pair, would go. Doctor Ryder and Mr. Zendt, who had evidently been conferring on the upper floor about some biochemical condition of the disease the doctor was studying, heard the raised voice of the electrical engineer and came down the stairway. "What's going on?" asked Doctor Ryder, twisting his watch chain, which hung across his ample chest. Roger, who saw the big charm, which hung on the chain, flicking its golden back in the light, realized, with an inward start, that the doctor seemed to be telegraphing with that "heliographic" flicker, as a Boy Scout would use a mirror to send a message from his camp to another, from a hilltop. "Oho!" Roger's mind was alert, "So he's telegraphing somebody." He hid his smile of triumph. "So you're in it, are you?" he mentally accused. "Well, two can play that heliograph game. I can read if you can send." While he listened to Mr. Ellison's angry commands to get that film developed or the Chief would be called up, Roger mentally received the flickers of the heliograph-like gold back of the twisting charm. "B-e c-a-r-e-f-u-l." "Warning him," Roger's mental comment was not audible. "More?" He saw the charm continue, as if the doctor was nervous. "R-o-g-e-r," it told him. "He's warning _me_!" Roger, grateful, and glad that his first suspicion had been unwarranted, waited to see if more would come, while his facial expression was meant to infuriate Millman and Ellison. "B-e-h-i-n-d y-o-u." Roger, turning his head, realized that there _was_ good intention plainly apparent in that peculiar flicker-warning. In the office doorway stood a stranger. Whether he meant good or ill Roger did not know. But he swung sharply, about to demand the stranger's right to intrude beyond the railing when he saw that the stenographer, Miss Murry, had sent him in. Roger, taking him in, saw a short, bald-headed, thin gentleman in a frock coat, striped trousers and a high silk hat. "I am looking for a Roger Brown," the man studied the group. "The office girl thought I ought to find him in what she calls a dark-room up some stairs. Can you tell me?" "I am Roger Brown, sir." Roger stepped forward. "Can I see you in private?" Roger saw that Doctor Ryder's watch ornament, emblem of a secret fraternity, was flicking around again. "S-a-y l-i-t-t-l-e," it seemed to counsel. "I can take you to my cousin's private room, sir." He nodded to show the doctor that he understood. "But I can say little about our work until my cousin is here." He led the way to the private door. He had told the doctor that he caught the two words. "So you are Roger Brown." The man was seated in the "thinking den" opposite Roger, who stood by the window and admired the sumptuous limousine with its chauffeur, waiting outside. "Yes, sir. How do you know my name, and what do you want to see me about?" "I know your name--no matter how. As for what I came about, I want to dicker with you direct, instead of with anybody else." "Dicker?" "For the Eye of--er--Aum or Ohm." "Why do you think you can dicker with me, Mister----" The man did not reveal his name. "You have the thing." "Who says I have?" "I know you have it, Roger. The point is," he glanced at his watch, "and I must hurry--the point is, you got it. Somebody else offers to get it from you and sell it to me but I think I may get a better price from you, direct." "Well, you can't. Who says you could get it from him?" "Young friend of yours--Tobias or something like that." "Toby Smith, huh? Well, he can't sell it because I can't turn it over to him. Only saw it in the Buddha's head, and in a man's hand. Maybe Toby already has it. Let's go ask him." "Can't waste time. What's your best price?" "Well----" Roger had an idea. "You leave your card and I'll get in touch with you." "I won't go higher than ninety thousand. If that suits, call up Clark, on Fifth Avenue, and say you are ready to close. He will understand, and will arrange everything. Good day." Brusquely, abruptly, the man left. Roger let him go. But when the limousine had drawn away, Roger marked down its license number, and within five minutes, from the Bureau of Motor Vehicle Licenses he had information. That license plate on the limousine belonged to a wealthy man, often mentioned in financial news. Roger, from a book of "Who's Who" learned more; he was a collector, among other things. But, Roger asked himself, was his wealth, position and hobby any reason not to place his name among those suspected, or at least connected with the Eye of Om mystery? And Toby. And Clark. They came uppermost again. If only he could get the hidden clue in his list! Chapter 34 TRAGEDY STRIKES AGAIN Without consulting his list, because he did not want to have it in sight any more than he wanted its place in the files discovered, Roger used the "thinking den" for just what its name implied. "Claws on glass," he reflected. "Click of a contact. Voice of Doom upstairs from Balsa-wood speaker. That's what the click was for. The plug-in that made the connection through the house-wiring from record to speaker-unit. The Voice again on a record that ought to have been blank?" He went through his list, mentally, to get all fifteen sounds clear in his brain again. "The call of 'Fire' and paper rattle sounding like flames," he completed his silent inventory. "Of course," he told himself, "the last one links up with the Voice of Doom on the record, and that links up with the Voice out of the speaker upstairs. And the click, as the plug-in was made is a link there too. Then, again, the thump in the corner that made me start the picture machine--that could have been disconnecting the plug-in. Doctor Ryder had thought it was going to be more, for he was with me and cried out, 'start the machine' or something." The clicks that he had first misread as dripping faucets in a washing-sink, that had turned out to be the safe combination being manipulated by an expert, he put out of mind as explained. "The claws on glass hooks up with the film that showed the ghost-kangaroo," he decided. "That can be side-tracked. Now, that leaves the talk that named Clark, after the Voice of Doom--all three times it could have been the same record, of course--what is left?" He re-pictured his clues. "The grind of moving rocks on the records. None in real rocks. A thump on the record. How do they tell me anything? The record was not really made in Tibet. It was made in America. I seem to remember that the Tibet voice was deeper than the one on the record. But why did the record add something not in Tibet? The rock rasp. Is that my real clue?" Puzzling about it, and trying to see what link there was between the thump and that additional grinding sound, he got no inspiration. His meditation was interrupted by the arrival of a caller, a man from the Museum of Natural History. He wanted the laboratory to work out some extremely complete system for protecting the museum's very valuable collections, such as the gem exhibit, and other priceless collections. Roger had to explain the absence of his cousin on "business" and to accept the assignment conditionally on Grover's acceptance. "Probably some short-wave system could be worked out," he said, and the caller left. Grover telephoned. Told of the call, he agreed to accept the commission and would call at the museum before coming to the lab., when relieved by Potts toward nightfall. Roger went back to his broken thread of meditation. An attempt had been made to get into his room. Millman had been caught. His motive, he had said, was to learn whether Roger played scientific tricks. Did that ring true? Or, as Roger felt, could he have wanted to silence a tongue able to accuse him about Astrovox? Roger tried to fit that theory in. "It just won't quite come," he mused, despondently. "But I must be considered fair game because I know something. There is the man who thinks I have the Eye. Having it wouldn't make them want to get me out of the way. Only the Tibetans would try that, and _not until_ I said where the Eye is hidden. And I don't know. Still, I have been attacked by some gas in the dark-room. Now what _am_ I supposed to know that would reveal the 'who' in this?" A shout from the upper floor broke his reflections. With a sinking feeling in his stomach and with heart skipping, he opened the private door and looked, listening, toward the stairs. Millman and Ellison, Hope and others, were stampeding toward the steps. "What was it?" he called. "Doctor Ryder--something has happened----" He joined the hurrying group. In the partitioned room, among the cages and plant-housing, on the floor, lay Doctor Ryder, with Toby standing beside him, his face looking horrified. "What is it?" Mr. Zendt came stamping up the steps. Ellison, bending in a crouch over the prone figure, looked up. "Did he faint?" he asked Toby sharply. "N--no, sir. Just fell down that way." "Are you--sure?" "Ye--yes-sir." Roger moved closer. "Is he--alive?" "His pulse is very low, but he breathes. Now," Ellison stood up, organizing them dictatorially, "Toby, bring ammonium--any form." It flicked through Roger's subconscious mind that the electrician knew chemicals. He had not used the ordinary, every-day "ammonia" but then he had not added the word to indicate the chemical nature of an ammonia solution. It might be because he was excited. "Roger, have the stenographer call a doctor--or an ambulance from police Headquarters is a quicker call. Zendt, what do you say this is?--Stroke? Coma?" The bio-chemist bent down, squatted. "Did he stand in front of that Beta-ray?" he asked Toby. The helper, apparently very much frightened, perhaps afraid of being accused of something, grasped at this eagerly. "Oh, yes-sir. He was right in front of it, working on them new rats he got in. Why? Will that lamp burn him?" "Those rays may have a disintegrative effect, some reaction in the human body. I can't say. I saw it was on, and asked." If that was a solution, there was tragedy, but not a culprit--a careless accident, instead, Roger mused. Was Toby's word, he mused, having made the stenographer contact the police--was Toby's word to be trusted. Or had he--what? The ammonia, and chafing of wrists, had no beneficial effect. Almost immediately a police car came; and soon afterward the interne from the ambulance was examining the man who had been put on the laboratory's emergency cot. The doctor bent close, sniffed at the faint breath. "Get the stretcher," he ordered abruptly. "What is it?" Roger's voice shook. "Poison, I think." He used their medicinal emetics as a first-aid measure, but almost without waiting for effects, took the inert figure away. Mr. Zendt, standing reflective among the group of stunned laboratory workers, suddenly confronted Toby. "Did he--drink anything?" "Y--er----" "_Did he?_" "I--no--yes, sir." "Water?" "Y--yes, sir." "Did he get it himself--where? What glass did he use? A clean one?" Under the fire of questions Roger saw Toby redden and then whiten, heard him stammer and try to evade. Out of it all came a sudden declaration. "I never give him no poison. He told me to get him a drink. I went to the cooler, and drawed water in the glass. I knowed it was clean. I always get told about washing everything the minute it's done with, and I did it even with the glass." If he had washed the glass, no evidence or clue to its former contents would remain in it. Was that, thought Roger, a way that a person might behave who had put something in the water? Or was Toby, as he insisted, innocent. But no one else had been there! Or had Zendt, formerly up with the doctor, put anything in that glass perhaps intended for either of the pair working there? It was a maze. And out of the staff, two were impotent. Roger shuddered. A thought turned him all goose-flesh. Might some one else be the next? Which of them? Maybe he, himself, might be. Or--he thought--was it all over? Was the real culprit caught? The police arrested Toby, took him away. Chapter 35 THE STALKING TERROR Roger left the laboratory. He located Grover. His recital amazed and stunned his cousin. "Astrovox unconscious still. Ryder hovering in the balance. Toby in a cell." Grover summed up. "Two attempts to reach you--and why? Can't you think, Roger?" "I've mauled my brain, but I just don't see what I seem to be expected to know." "And the missing jewel," groaned Grover. "Where is it?" "I haven't seen it since Clark put it in his pocket, in the temple, Grover." His cousin considered the matter as they took lunch in a quiet corner of an uptown restaurant. "You lock up securely and make certain that the devices all work." Grover said, as they separated, "I shan't have to stay with the old man, because it isn't expected that he will regain his wits for at least several days. I must go to the museum. Business has to go on. Then I will have a talk with Potts. We have given him what the French call a 'white card'--a clean slate. But--I want to question him. He might have picked up the real gem. He could have realized what a find it was. He may not have discarded it. And while I hate to suspect him--" "But he wasn't there, today, when Doctor Ryder--" "How do you know?" Roger was silent. Like Grover he hated the idea; but Potts had been free, supposedly resting. He might have been around. If anybody could know ways to get in--oh, it was not thinkable, though! Much more Roger preferred to mistrust the electricians, or the bio-chemist. On his way back he stopped at home to get the record carrying the "fire" and crackles. He would need a fresh record for that night. With his package he returned to the laboratory. Everything was quiet, there. The men, in their activities, were sober but busy. Zendt greeted Roger. "How is Astrovox?" Roger told him. It was suspicious, the young cousin decided, that Zendt was so anxious. Less so, it seemed, about Doctor Ryder. He made no inquiry, though Roger, coming in, had called up the hospital to learn that the man was out of danger due to the prompt action of the interne at the laboratory. He must be quiet, for ten days or, at least, for a week, Roger had been told. "Astrovox," he told Zendt, "is unable to say anything, and they don't expect anything else for days." That, he hoped, would "spike" any intentions the man might have to harm the old astrologer. Not wishing to say more he hurried to the dark-room, quickly put the waiting films in a time-and-temperature regulated bath and went out of the place for the eighteen minutes that would elapse during development. He busied himself clearing out the waiting requisitions for minor needs from the stockroom, tested the glass used by the doctor with no result, and then put the films in hypo. for fifteen minutes, staying in the open rooms during fixing period and washing afterward. He was not going to be caught in that dark-room, with Grover and Potts away and some stalking menace quite possibly still abroad. His list was still in the file, he made certain. He had thought that it might have been taken; but he realized that whatever was on the paper was also in his head, and that was why he was endangered. When it came close to closing time he helped clear away used trays and other chemical apparatus, washing-up. He gathered up all films and got ready for the next day's work. The developed and printed film he left on the drying drums, not caring to stay long in the dark-room. When, close to the office at all times, he was certain that the staff was absolutely out of the building, he began a careful and thorough, but hurried series of operations. His decision to stay there all night, discussed with Grover, had finally been agreed to by his older cousin. At home, there was no way to avert the trick used before. The fuse box could not be guarded unless they hired a Falcon patrolman. That the laboratory was more impregnable had been proved the night before by the effort used to enter. The fire, set off probably by a pole carrying a light, inserted from above the telescope, had been assurance that even the skylight was considered too risky by whoever had wanted to enter. That one had set the fire, hoping that firemen would have broken in, giving him--not her unless the stenographer was suspectable--a chance to run in with them. What _they_ could want (or what _he_ could want), Roger did not seem able to decide. Not the laboratory's secrets. When the false gem had been sought in the safe, nothing else had been disturbed. Roger, determined to stay all night in the laboratory, made his preparations with thoroughness and care in spite of his speed. The old microphones set at doors, windows and other probable entrances, he tested. The cameras he took out of circuit. They would not need to record, because no one must get in to be snapped. From the upper room he resurrected the old shadow-box with its panel of lights, connecting them into circuits so that the least disturbance by any microphone, even a vibration of its sensitive diaphragm by slight sounds, would cut a relay and light the right lamp. The connections of the magnetic plates he traced, to be sure no one had cut a cable. Where they all came together at the transformer Roger transferred the connection from the 180-volt step-up to the next higher output. Anyone touching any plate must receive a 300-volt charge. He would not risk anyone getting away, granting that such a one got past the bolts he wired fast, as he did with window catches. The fuse-box bothered him. If an intruder could in any way get in and pull out fuses, perhaps all his precautions to hold them would be futile. Presently a solution of that difficulty came to his trained mind. With the fuses left in place, he disconnected the cables that fed the protective devices, wearing heavy rubber gloves and with rubbers on his feet. Taking that set of flexible cables back behind the furnace and to the main box of the electric company input, he risked later censure for tampering with their property by breaking their seal on the box, throwing off the big, main switch, and connecting-in his cables to the main line just within the input lines. He closed the box, sealed it with the switch again in the "on" blades, and knew that any outsider must be ignorant of his precaution. The fuses could be pulled, the wires at the switch-boxes could be cut, and still his plates and microphones would be actively charged, potent and effective. Roger, effectively sealed in, he felt, sat down with the supper he had ordered in, saving milk and sandwiches for later, and ate with a feeling that he was safe. Half way through the meal, with an inspiration, he took a charged wire from the main-line up to the telescope still poked up out of the skylight. He had climbed up. If anyone started to climb down--what a shock that telescope would give. Contentedly he closed his meal with a big cream-puff. Soon after that darkness came. Roger, unwilling to discover his presence by lighting a light, sat comfortably in Grover's "thinking den," and put his thoughts to work on the problem of that list of sounds. If he had only guessed it, his very elaborate precautions had been overdone by just one protective effort. Night chased the western glow away and brought stars to look down upon a very quiet, apparently deserted building. Roger, restless after an hour of fruitless thinking, wandered at slow pace toward the upper floor, planning to start there on an inspection route that would kill time and give new assurance. He had not completely mounted the stairs when he heard a sharp, almost explosive crackle. His eyes were dazzled by a flash as if it had begun to storm and lightning had flashed. He stood, transfixed. The flash died, and to his amazement he heard a queer sound as if splintered glass were dropping, tinkling and scattering; and yet it was a muffled sort of clinking noise. He summoned his best courage and with shaking limbs crept on up to the second story. There, looking around half-fearfully, he was more amazed than ever. In the gloom, objects he knew well by location loomed without any apparent change. The telescope pushed its long barrel upward, the table and chairs, cabinets and cages, seemed as before. He threw on a switch for light. None came! He stood there, baffled. Had the power-house cut off their "juice" or had a dynamo cut out for the time? No. There had been that detonation and flash. A torpedo such as he had made? No--more like the spark from their high-tension transformer jumping a gap. As he stood there, something below him went over with a crash! Chapter 36 A LAW OF NATURE Roger, in the dark, hearing the echoes of that crash, felt fright that nearly swept him into unreasoning panic. Not quite, though! With every effort of will he held his muscles steady when he wanted to run. Clear faculties would be all he had left to pit against an adversary certainly more than simply vindictive. The unknown was almost as brilliant in mind as was his cousin, Grover. Grover? Why _he_ would have thought out that one and only way in. Roger, forcing himself to be calm, realized at once how his extra protection had been turned against him. He had wired to the telescope. Some one, climbing the candy factory fire escape, looking down from the roof of that building, could, by the angle of view, have seen him attach that wire, peering down past the bulk of the telescope. Thus charged, all the miscreant had to do was to lay a wire or rod or any metallic carrier, from the candy factory drains or rainspouts across to the skylight. By pushing it into contact with the heavy charge in the telescope, a short-circuit could be established that would blow even the main-line fuses. Thus, and in no other way, could the devices have been rendered impotent, the locks be only held by wires which a powerful implement in hands so adroit could easily sever. Even the alarms would not work. They had undoubtedly operated at the instant of the break, and in time a Falcon patrol agent and anyone who called police from home, would help him. But until then!---- He must, Roger knew, be his own protector. At ten Grover would arrive, using a pre-arranged signal. Not for an hour would he come. "Self-preservation is the first law of Nature," Roger's mind in a whimsical flash reminded him. Instead of throwing his faculties into a turmoil, the imminent danger calmed him. That much Grover had made him learn. By opening a way in, the miscreant had, for Roger, made clear a way out. He was, then, in no vital trap. He could afford to drive back panic, to think carefully what to do. If the whole building had been short-circuited, the telescope was no longer charged. He had climbed it. Climb it he could again. His problem, though, was to trap his unknown adversary if he could. With no electrical help he must think out a plan. It must be clever, Roger knew. His menace was from a man as brainy as was his cousin. And that, Roger felt, was a compliment to a very unjustified person. He thought he knew what the crash had been. Something deliberately upset in the cellar, to scare him. It had come about as long after the flash as would have been consumed in rising to the roof on a rope, scuttling down the fire escape, opening the cellar coal chute, and climbing down. He estimated the time that had since elapsed. The adversary had by now gotten up the cellar stairway and would be on the ground floor. Would he come further or try to lure Roger down, the solitary youth wondered. He must let that become apparent by what his keen ears would detect. He discarded all but attentive listening, making his mind focus on some plan to trap his adversary. What his mind had, with seeming whimsicality, obtruded during his moment of terror, came back to Roger. "Law of Nature." seemed to prod at his thoughts. _What_ law of Nature? How would it help? Almost as though some inner monitor was going to save him, a mental visualization of the laboratory seemed to become clear to his mind. He saw the ceilings, with the slim pipes that ran here and there to openings; and he connected the vision with the fact that their fire-protective apparatus had _not_ functioned, when the alarm had been set off. The tanks of heavy gas, under pressure, were still charged. "Gravity!" Roger's mind grasped at an idea, "that's the Law of Nature I am trying to think up." As if he had received a key to a tantalizing problem, Roger solved his course of procedure in a flash. In his mind he ran over their stock of chemicals. Hydrocyanic acid, a stinging, powerful combination of cyanogen and hydrogen; and hydrochloric acid--and many more. One of these, akin to a tear gas, would do. But he was cautious, and in spite of the pressing uncertainty he paused to be sure he would not take for his plan anything that could, in combination with the fire-smothering gas, cause an explosion. Almost at once he had the solution. Sulphuretted hydrogen--the common, refined gas that comes in the city mains from gas plants to stoves and gas jets--_that_ would not explode in combination with the heavy gas in the compression-tank system! He wanted a gas that would stupefy: but he needed to be sure that it would lie, close to the floor. The gas in the fire-prevention apparatus was such a heavy gas that on being liberated, under pressure, it would settle rapidly, diffusing and spreading, as if it could be likened to a cloud, surcharged with moisture, settled on the earth, enfolding it like a blanket. There, in the upper room, was the means of releasing the city gas, which, Roger knew, would stupefy of its own constituents--even kill, in time. He did not intend to give it that much time! He merely had the desire to put his assailant into a state where he could not leave. Either the intruder was hesitating because of Roger's silence or he was very quiet in his actions. Roger, equally quiet, was extremely active. He had unlaced and had slipped off his shoes at once. On stocking feet he tiptoed to the large gas outlet set into the wall for use with Bunsen burners or gas heaters used in experiments where a regulated heat was needed. This he opened, full, by turning the valve one half a revolution. Darting swiftly away from its low, humming release of a heavy flow, he ran quietly across to the thermostat on the wall, connected into the fire alarm and release system. Under it was a manual lever, one to be operated by hand, in any emergency where the thermometer failed. Swiftly Roger threw this on, and with his handkerchief tied over his nostrils and back of his head, for already he smelled the gas of the opened outlets, he swarmed up the telescope. The house-lighting gas, he knew, would be held down, running to the lower floor down the stairway, and the amount released would be enough to stupefy quite soon. Even if the adversary climbed the stairs, he would be in a bath of the sleep-inducing sulphuretted hydrogen. With his arms and legs helping him rise, Roger clambered up the inclined metal barrel of the telescope. At the top, above the flow of smother-gas to kill fires, he paused, listening. Not a sound. To the roof he clambered, and sat on the coaming of their skylight, looking down, waiting a few moments in case the other tried to come up. Below him all was silence. Chapter 37 REVELATION! Soon Roger felt that he had given the gases time to flow down, to produce at least inertia or coma. He must not dally too long. He scrambled up the rain-drain as he had previously done. Down the front fire escape of the candy factory he scuttled. No one seemed to be near, as he gave a hasty survey. Then Roger stiffened, on the lower stage of the fire escape. On the other side of the street some one emerged from a doorway. Hearing the man walk rapidly across, Roger dropped, landing in a crouch that broke his fall. He meant to accost the person openly, and risk consequences. "Stop!" he shouted. He got almost as great a shock as had come from the flash of the short-circuited telescope. "Rog'!" "_Tip!_" He recovered from his daze. A cold horror stole over him. Potts, their handy man, around there. And no one else. Or--was another inside? More probably, smelling gas, Potts had retreated the way he had come, escaping. "What are you doing here?" Roger demanded. "Watching. Grover bid me to." "Well, we will soon know. He's due at ten." Roger pretended he had something in his coat pocket. "You're covered, Potiphar. Don't try to escape." "Me?" in surprise. "Are you batty?" "Somebody short-circuited the telescope after seeing me wire to it, to be sure no one got in to attack me. You'd know how to do that!" "Oh, yeah?" There would be a way to tell whether Potts was aware of the gas. "Easy to prove you're innocent. Let's go in and search." Briefly, not entirely, he stated the case, omitting the gas. Potts drew back. "We ain't--armed. I see through your scheme, with your hand in that empty pocket. Nix. I go in when we get a cop or somebody." He might know about the gas and that would account for his lame excuse. It was not like Potiphar, Roger thought, to shirk danger. "All right. But I've got to get in and shut off that gas." He had to let Potts go, just in case there was any other inside the fume-filled lab. Roger, running to the drug store, where an ex-service man was on duty as he remembered, begged him to find an old gas-mask. The man hunted through some things in a back room, and gave Roger the proprietor's old war trophy, which Roger, with his aid, adjusted. Thus protected, and aware that Tip still waited, he ran in with no fear of setting off electrified alarms, dashed up to the second floor by aid of a flashlamp picked up in the office, seeing no one. The gas he shut off hurriedly and then he set the thermostat lever back in case the tanks held more unexpelled fumes. Throwing wide all the windows on the ground floor, he wished that they had current for the fans to blow out more quickly the gases. Potts, waiting, wanted to quarrel about Roger's suspicions; but Roger sent him to the drug store to return the mask and call the lighting company, tell the rough conditions and get an emergency squad in to re-fuse and seal their input boxes. Grover came along about the same time that the truck finished and departed. Quickly, on the sidewalk, Roger recounted the situation. With current on, in spite of the company's annoyance at this tampering with sealed boxes, Roger, smelling less gas than would be dangerous in a momentary invasion, set fans going and rushed out. On the pavement they discussed conditions. Roger could not help feeling that Potts was to blame, had been, in spite of all loyalties, in face of past good conduct--Potts had been his adversary. "He was the one who put the record on my home recorder, with the fire-call on it already." "How'd I know?" flared Potts, "I--it was with the unused ones." "Oh, yeah?" Roger threw back at him his former grunt. "Tip could have substituted an exposed film for the unused ones, so that we developed the animals. He could have taken the film to the zoo and got the kangaroo, maybe with an ape. We can check," he insisted. "He could have transferred the first culture meant for the rats to the place behind Doctor Ryder's racks." "For that matter, Grover could of did any of them. He could have as much cupola as me." "Cupola?" broke in Roger. "He means 'cupidity'," remarked Grover, "thinking about the Eye." "But _he_ says he found it. Admits it. And Mr. Clark vows he had blundered, and threw away the good gem," persisted Roger, sure of his incriminating clues. "Who says the gem was left in India? Who had the sense to pull fuses, to stop our devices? Who else but somebody trained by you, Grover----" "Well, _you_ was trained, too," cried Potts, angry. "The gas is expelled by now," Grover had not lost his cold, serious expression. "There is desperate need for action, more than for recrimination. Let's go in." They sat in the office. Roger recounted the clever warning with his watch charm on its big chain, given by Doctor Ryder, and all the mystifying, or incriminating conversations and occurrences, including a fuller account of his experience in the dark-room. "I suppose the poor mice are gassed," he muttered, finally. But Grover was not listening. "Tip," he stood up, "help me push this desk aside." Potts did as bidden. "No shot was fired in here," Grover snapped. "When Astrovox was later assaulted. What happened, Roger? Don't you know? And _you_ exploded a torpedo to call attention to a certain place and away from some other?" Roger was all at sea for a moment. "Astrovox was leaving. The other fellow didn't know that." Grover had caught some clue or hint, somewhere. He was as active, as alive, as if he had never been a cold, precise, restrained scientist. "Some one wanted us all to run here. As he produced the summons, Astrovox ran in. The man realized that he was recognized. Poor Astrovox! Well, he will recover. And--see there!" He pointed to a brown, scorched spot under the far edge of the desk as it had been before. "A foot, on an explosive, such as your torpedo, Roger. Evidence out of sight. Evidently had no time, later, to remove the burn, but did remove the exploded detonating cap. Rubbed his shoe over it. See the scorch? Test and you will get something like a gunpowder reaction. Maybe you can scrape up dust that would test out with the nitric acid to show the stains of explosive gases." Of a sudden he straightened up. "The acid test!" Roger, and Potts, gaping, had no way of following the swift deductions which the Mystery Wizard, on the trail at last, made. "Roger--no, Potts, you do it--run out and bring a taxi. Roger, you go up and watch in the stock-room, but keep out of range of any missile sent through the skylight." He began writing as Tip rushed out and Roger obeyed. On his way, as Potts came racing back, Roger heard, "Go to that address. Bring every shoe you can dig up. And get what's written below, on your way back." He locked the door after the man departed. Roger heard the alarms being re-set. Then his older cousin joined him. "What told you?" Roger knew that the Mystery Wizard was, at last, living up to his name. "Claws-on-glass. Think. That was one big error. You have told me the truth." Roger was baffled. He saw nothing that he had said which linked up with the queer, sizzly, scrapey, frying and clicking sound. Grover, with the upper floor extension plugged in, made call after call. "Grover Brown, calling Chief of Police--hello--that you? Chief, we're going to have a round-up at the lab." The usual calm was nil-minus. "Will you?--Glad if you come with the men--I will ask you not to let the men be seen--Wait at corners, across the street--Watch the skylight of our roof for a blue signal--Yes, then come in a hurry--Good-bye." To Roger's stupefaction he repeated almost the same instructions to the men from Tibet, adding, "And--I promise to return to you the genuine Eye of Om--Good-bye." "But what told you, Grover?" Grover glanced at his wrist-watch. "The one clue that no one else could furnish." He stood erect, alert, his eyes glinting. "We've got work to do. Let's get going!" Chapter 38 THE VIGIL "Blue glow," Roger gasped. "Are _you_ going to have fireworks too?" "No. You will adjust the big sun-lamp so it sends rays upward. Put the blue filter from the star-reader's plant beds on it. It is only fair that part of his equipment should help catch and round up the one who struck him." Roger, with nothing but thoughts to occupy him, went to prepare the signal. He could hear Grover making calls. To a police Bureau. To his staff men. To Falcon's patrol agency. To Roger it appeared to be as dense a mystery as ever; but to his brilliant cousin something had torn aside the fog. He tried to fathom that evasive clue. He went over his ideas. Claws on glass? No! Then what, besides? Something he should recognize in the light of what he knew. Something that the miscreant had imagined him bright enough to have guessed, perhaps. It escaped him, eluded his every attempt to read that riddle. Only a short time was he allowed to concentrate. There were hookups to be made. A chair in the store-room was to be wired down two legs, positive and negative wiring, a plate of metal as thin as possible was to be found and put on the seat, with small clamps to hold it in place under a thin covering cloth. It was to be left where it stood, but two wires must be taken from a wall outlet, led to small, flat disks like microphone diaphragms, tacked onto the floor at a place Grover designated. With that done and the wires fixed in a plug-in to fit the outlet, Roger left the circuit disconnected as ordered, and busied himself leading wires from the sun-lamp, with its blue cover-glass, to the stock-room shelves where they must be so set that a can of film, shifted and dropped over them by hand, would complete the circuit, act as a switch to light up the sun-lamp. Grover came up, inspected, and pronounced the work well done. "Now, get a nitric acid test-bath ready, in a big container--and have some wax melted and ready for the test for exploded gases." "Whose hands did we overlook?" "No hands. Feet." Grover answered, alertly, and with a smile--mystery-solving seemed to transform him from a staid, self-contained scientist into an eager, boyish experimenter. "Shoes?" "Exactly." "His?" "Right." "Then--whose?" "If you are too dull to have read your own sound clues, Ear Detective, far be it from me to dull your wits by telling. Think!" Presently Millman, Zendt, Ellison, Hope and several other staff men, in pairs or alone, arrived. They were eager, excited as they questioned. Grover, picking Roger's list of clues out of his file, presented it and suggested that what he had learned they could learn, while Roger recounted his own experiences up to date. That was done; and they pored over his list. Grover, getting a lot of amusement out of their guesses, chuckled to himself; but his younger cousin felt that he was watching them to see when the guilty one would crack and admit that he was cornered. Who, besides, could be guilty? Doctor Ryder was in hospital; so was Astrovox. So, in jail, Toby Smith was out of the night's excitement. To his amazement, a police car, arriving, brought an officer who brought in the last captive he had been thinking about--Toby. The men seemed to have found no light in Roger's list. Roger, who had heard their sane, or wild surmises, suddenly sat up. Some brain cell, stimulated by the continual stress of cogitation, spoke its concealed message. "I know--Grover--how dumb I've been." He scribbled a name on a slip from the office desk. Grover nodded. "You should have seen--heard the right answer long ago." "I left it for the Mystery Wizard, so he could keep up his reputation," grinned Roger. The Tibetans walked past, identifying their presence, but went on down the street. Grover, watchful, looking out of the window, made a signal that he had noticed them, and then suggested that they all go up to the stock room. There, in the silence, with no light except that in the monitor-panel which Roger had set up to show which entrance was used when they could expect callers, they sat around, puzzling and trying to make Grover speak, although any one of them could have been suspicious of any other, the way they talked. A light announced the arrival of a visitor, but Grover did not move. Potts, he knew, was coming; and his inference was the right one. Potts, with a bagful of shoes, came in and dropped his find beside Grover's chair. "Take this chair, old fellow," Grover was very grave and had an air of trying to make up to his handy man for Roger's mistrust; but Roger knew that the chair moved over so casually had been most carefully set on two small disks, not charged yet--but how easily so made active agents for trapping the sitter! "Now we must be patient," Grover stated, arranging the nitric-acid bath, paraffin heater and other apparatus on a table. "I shall test some shoes, presently, and I expect them to verify my judgment. In the dark, though, I shall give the miscreant one chance to secure his Eye of Om before I denounce him." Someone, in the dark, shifted his feet, Roger imagined, uneasily. "You don't mean to say you left it there!" It was Toby who made the gasping admission in his sudden excitement. _He_ knew it was there! "Still where, for all your seeming denseness, you worked out its place," agreed Grover. "If you care to, you might apologize to Roger for telling the millionaire collector that _he_ had it. Of course it was to avert all suspicion from yourself." "Aw--" He did not have time to complete his denial or blustering cry. A light in the tell-tale went out. The main door was opening. "Nervy," commented Grover. A strange, heavy thudding, or thumping, accompanied by something as much like the drag of a heavy rope as any other sound, told Roger that some weird development was coming. Could it be--really, a kangaroo? And why, then, was there a strange chattering and jumping sound? What would they see? Those sounds grew louder. The stairway shook. Low growls or words of command sounded. Some animal, approaching. Or animals! No man--Roger was sure. Chapter 39 THE APE AND THE KANGAROO Whatever was in the laboratory, it was coming straight up to the second floor. Roger, crouched beside the floor outlet to await a signal to plug in and electrify that chair, wondered why Grover did not move the film can, make contact and light the signal lamp to summon the police and the Tibetans. Instead, Grover spoke, low and meaningly. "The first man who gets up is the guilty one!" Zendt, who had started to rise, sank back abruptly. Ellison and Millman stayed as they were, half bent forward. "Guilty nothing!" Toby spoke in a rasping voice. "Think I'll sit here and let something attack me?" "You heard me," snapped Grover. Roger knew that it would be a question of seconds only; and they would then see the approaching creature. There in the dark it was a tense moment, and a nerve racking one. Louder, thudding on the floor, with a strange dragging sound at the end of each pause, came the approach. "Roger--that bag." "The shoes, Grover?" in dismay. What was the matter with Grover? "Quickly. That bag." Roger lifted it, and Grover, snatching it, opened the paper sack, dragged out a bulky object, just discernible in the dim light they had from the tell-tale panel. Roger gasped. "Boxing gloves!" "Lights!" snapped Grover; and as Potts, lifting an arm, snapped on the wall switch just above the place his chair occupied, Roger saw his cousin pulling on the padded mitten-like objects. Whether the rest knew or not, that told Roger what to expect, if not the whole situation. A kangaroo. A boxing kangaroo. The one he had photographed when he had questioned its attendant who had said no pet or trained animal had left the stable. In the next room something stopped, and there came, not loudly, a low command. There was an interval of suspense. What, Roger wondered, was the condition in that partitioned place adjoining their waiting room? After a momentary wait, and more seemingly guttural commands, the thumping was resumed; and the animal, in short hops, came to the entrance door. There it paused as if dazzled or surprised at the light or by the crowd. Behind it, in the other, darker room, shown by their own light, Roger saw a hairy, man-like creature, either chimpanzee or some other large mammal it seemed to be. The kangaroo's keeper, he assumed. Just as in the under-exposed film, where the ghostly ape and its Australian companion had seemed to dance, the kangaroo hopped in, while the ape, grimacing and beating its chest, danced in behind it. Straight at Grover leaped the kangaroo. It wore boxing gloves! Roger, crouched, tense and frightened, saw his cousin, with a typical boxer's stance, prepare to carry the coming battle to his astonishingly expert antagonist. In that room, while the company shrank back, against walls, pushing their chairs out in front of them, leaving a clear space, the animal and the man closed in as fast and as bizarre a contest as Roger had ever viewed. Not clumsily, but with lightning-quick jabs of its short forearms the beast lunged, taking blows without a sound. Grover, clever through gym training, fast on his feet, evaded the fairly clumsy leaps and lunges. At every chance he got in a blow. If, as Roger inferred, the ape was indeed the trainer, the bulky creature bore out the idea. Grover had to watch the skipping, leaping hairy thing that tried to get around and catch him; and also, as far as Roger could discern his cousin's tactics, Grover seemed to be so handling his leaps and side-wise ducking that the ape would be mostly near to Potts who sat, tense, but still, in that chair; and Roger, crouched by the wall outlet, wondered if he, the handy man, meant to take part and if Grover had foreseen it. "No you don't!" Grover seemed to be talking to the kangaroo, but of course it was the ape he really meant to have hear, Roger knew. "You keep far from the cabinet. What if it is ... och--oh! Missed me, old fellow ... even if it is unlocked." As though telling a story as he dodged and ducked, Grover always talked as he maneuvered, his breath well conserved by his ease of action. "So there _was_ a scientific student who turned to jewel theft! ... he did want to get rich quickly ... he was clever ... made a specialty of locating ... prized gems.... Through a jeweler named Clark, he ... he got into contact with those ... who would pay well ... got the gems ... used the jewelry place as a clearing house...." In that fashion he began outlining a solution. "Heard of the Eye of Om, didn't he?... Went to Tibet, taking Toby ... didn't dare make a stab for it, though...." Grover jumped back so that the monkey missed grabbing him. "Got through Clark a man ... who would pay fabulous price for that Eye. And ... worked out plan to have it so cleverly stolen _for him_ that he would never be suspected by Tibetans or other gem thieves ... oh, you would, eh?..." as the ape made a lunge and Roger, avoiding it, had to drop to his haunches to avoid the boxing kangaroo's leap and stroke, "Would, eh?... try to get to that cabinet.... Like to paw the Eye of the Buddha, eh, would you?" as the ape started to take a part by coming up to grasp him from behind. Roger was about to shout, but he saw that Grover, like an eel, slipped aside. He did not strike at the ape. "The gem robber knew he would be suspected if he ... took the Eye ... returned to America ... made an elaborate plan ... would use science ... chose our lab...." Grover, his cousin saw, as did the rest, kept maneuvering so as to keep the lunging paws approaching as he backed around. For some unseen purpose he seemed to be manipulating his actions so that he could get the ape and the kangaroo into some desired relationship or position. Roger, still at his place, not daring to desert his post, saw the ape back toward Potts. Instantly, as though by some previous order, Potts snapped his body out of the chair, and with his arms, catching the thing that walked upright like a man around its torso, he dragged its shaggy body backward off the huge feet and flung it into the chair. "Plug in!" Still dancing backward from the leaping kangaroo, Grover shouted. Roger, checking the tremble and shake of his excited hands, swiftly drove home the prepared plug and at the same instant from the thus electrified chair rose a sheer animal howl of pain and fright and fury. Still alert, Grover had a moment to catch his breath. As if startled, the kangaroo paused. On haunches, its forepaws were hanging down over its pouch--it was a female with the pouch to carry its young!--while from the chair came the most ferocious grunts and screeches. The trainer, thought Roger, was an actor in spite of his surprise. He maintained the animal voice well. As if prepared for the situation, Potts dragged from a pocket some light, strong electric wire, and with gloves of rubber which Roger had seen him getting ready, he managed to get the wire around the beast, or rather, as Roger put it to himself, the man in the animal hide. "You can cut the plug out, now, Roger." Grover, with a wary eye on the still quiet kangaroo, which had not moved, spoke the command. Roger obeyed. Released from the shocking cycles of current, the thing in the chair growled and struggled against the bonds which Potts had cleverly wound to prevent use of arms or legs. So powerful, though, was the beast, that it once upset the chair and had to be righted, growling and using guttural imprecations or shouts of hatred. "To go on with my story," Grover calmly confronted the quiet kangaroo, "the man chose our laboratory as the base of his plans. He came here. To start his operations, he watched his chance one night, and hid in our large refrigerating unit, that is in the spare-stores room, since we used it to test chilling processes for food shipments. "Being unsuspected, he had been able to make certain preparations. First, he put the culture intended to inoculate some white rats, into our chemical section, half-hidden, but purposely left where it could throw suspicion on a certain person. Then, when the rats had been inoculated, but with a harmless drug that made them sleep, he was ready for his next step." To Roger's surprise, everyone had been so amazed and so startled by this calm recital aimed, apparently, at a dumb brute that sat back with drooping, glove-shrouded forepaws and listened!--or was too baffled by the capture of the trainer to continue the battle--the staff had settled in the chairs again. "This mysterious, clever criminal," Grover coolly proceeded to tell the animal his theories and deductions. "This former student of various biological, chemical and related subjects, bribed an animal trainer who had a vaudeville animal act, to let the animal used in the act come here. He wanted it to be caught if any plan failed, so he could disappear but the animal could not tell on him." He bent forward, and quietly removed the laced ham-like gloves from the beast's relaxed paws, and it seemed not to resent the act, but let the free forearms hang loosely across its stomach, and pouch. "Borrowing the white rats from the act, this miscreant prevented them from being inoculated by exchanging labels on the culture, later recovering the labels as the bottles emptied were thrown to the fire. The labels, on the real culture again, were put where they would seem to clear someone by incriminating him through circumstantial position in the racks. Really, though, they had a different purpose." He startled all but Roger. "The appearance was that the man whose rack they occupied was being persecuted. In reality, he did it himself, to make me suspect every other staff man." "Not Doctor Ryder!" Millman gasped. "You have named the culprit." "But he's poisoned, in the hospital----" Grover went right on, ignoring Ellison's shout. "He confused us by 'stealing' the rats, and in other ways, because he wanted us to think of every possibility but the real one." "And that was?----" prompted Hope. "He wanted us to help him take a false imitation of the Eye of Om to a Tibetan temple, replace it for the true one, which he could then sell for a great sum. In other words, what we thought we were doing, helping restore the true jewel, was exactly the reverse! "We innocently helped remove the True Eye of Om!" Chapter 40 THE MYSTERY WIZARD'S SOLUTION While the beast shackled in the chair kept up its hoarse growls and struggles, Grover outlined, for the benefit--it seemed--of a kangaroo--or the one in the chair--his deductions. "Was that clever? You know it was. To plan to steal a sacred gem under the pretext of replacing a fake one with the true Eye." Roger had not guessed that, nor, by the exclamations, had the rest of the group--or most of them. "The mystery of the white rats, supposed to be deadly menaces because we thought they were inoculated with germs of a spinal malady, got our attention turned to every possible idea but the real one. "To add to our consternation, give a ghostly touch with the animal 'spooks' on a film, this clever thief made a record of what he recalled about the Tibetan Buddha's 'Voice of Doom.' Like most criminals, he overshot his mark, adding the grind of rocks, when in truth there was no such grind. The sound was caused by wind, always howling across the Himalayas, coming through a wind-tunnel cut in rock from the base of a cliff to the lamasery temple on its crest. "He made a record, with moans, cries and groans, and added the effect of the rock closing, from his imagination of what would be right." That record he had managed to slip onto their own recorder-reproducer machine, with a hookup which Roger knew all about, Grover went on. The weird manifestation had startled them, while watching for the man, one night. With a Balsa-wood speaker hidden flat on a dusty shelf, he had caused a spooky voice to draw them up where the prepared film, in a can carefully re-sealed, was handy to be taken and, later, developed, to complicate mysteries further with the spooky animals, he added. "That was all for the reason that he had to bring in Tibet, logically," went on Grover, "he had to prepare us for the fact that he was in danger from the Tibetan vengeance. Of course, by this time, the staff knows, as we do, who I refer to." Of course, Roger decided. The others nodded. Who, but the guilty man he accused, could be meant? He had said the man was menaced. "Doctor Ryder was the only one who claimed he was threatened," said Millman, "and I suspected Roger of playing jokes!" "Well, I suspected you when you came to my room," retorted the youthful listener. "And I did not know whom to suspect," Grover took up his story. "Clues pointed this way and that. Appearances are easily falsified and I tried to dig past them to truth--only, I lacked the right hint, and never dreamed that a gem was to be stolen under the pretext of restoring it! That was easily planned, for once the gem had been seen, perhaps photographed with a watch-camera or some small photographic device, a man like Clark, working with him for a share of the profit from various gem sales, could reproduce in imitation the green jewel." Toby, he inferred--and the youth eagerly attested the truth of the inference--had been paid well, being a former helper at the Clark store on Fifth Avenue, but out of work--had been paid to sell the supposedly "real" Eye, its facsimile, for an absurd amount, as he had accepted a movie camera. "I fell into the lure," Grover hurried along, "because, for a time, the Tibetan Voice of Doom manifestation, and the robbery of our safe, confused me. It was easy to do that last by de-fusing our cellar switch-boxes, a point I had never thought of. Scientists, like criminals--or average people--trip up often enough on some minor point in a plan." Because the radio would allow him to be in touch, and for the sake of the travel, adventure and scientific aid Roger would get and give, his older cousin confessed that he had been glad to see Roger help the supposed replacement of a sacred relic. "Clark was brought in cleverly by use of a record. It was the same one that had been used for the Voice here, and when the needle was dropped onto the unused part, it made a thump that was one of the sounds of a series of clues which puzzled Roger and me, because the _appearance_ was that it was all one recording. "The trip to Tibet went off as scheduled. Roger, really a sort of 'bait' because of his youth, was, as hoped, taken up to the lamasery as a sort of curiosity--a young American well up in scientific methods and operations. Innocently he played the thief's plans, and still the very apparatus that he insisted on taking there made the lamas suspicious, especially one of their wiser men who had been out of their country, who understood English, and who had read Roger's memoranda of radio talks to and from lamasery and camp. "With Tibetan vindictiveness, they let him hear the Voice of Doom, probably operated by a concealed priest in the hollow image, and then consigned him, and Potts, to the tunnel. By sheer wit and scientific knowledge Roger found that he was in a sort of whistling tube, operated when the rock door was opened, by wind. He worked out, with Tip's wise help, the secret, and they escaped. "Clark, when Roger got to camp, took the supposed Eye and with Roger watching and unsuspicious, actually replaced the true Eye with the false one he and Ryder had brought along. He had another, and to make Roger think he was genuinely through with the stone, so as to be clear if any Tibetan revenge developed, he threw away one more imitation. Potts, worried about the levers having been wedged which he considered an error of judgment, went back to repair it." So interested were the men in following the developing solution that they had forgotten how bizarre was this relation of a mystery and its unveiling--to a beast. The animal seemed fascinated, or cowed, or subdued in some way. Perhaps, thought Roger, the plight of the hidden keeper made it tame. Grover drew his theories into shape. "Naturally, with the real gem, Clark and Ryder made all speed to radio the prepared airplane. It met them. In Bombay, as he had no desire to be further involved, Potts discarded the false gem he had picked up." Then, proceeding on pure deduction, Grover felt that the Tibetans had discovered their real loss, had discerned that Roger and Tip had solved the intricate tunnel secret and had escaped. To write, with Roger's discarded note book as a guide, in a semblance of his writing, was easy. The letter had come by fast mail steamers and had further confused him. "Then the thief, with the gem in his fellow-worker's possession, encountered difficulties," went on Grover; "the man who had been intending to buy the jewel probably became frightened, afraid of the danger that the stone might bring around him. So many priceless jewels carry curses, or bring disaster, that he must have gotten 'cold feet' and a new buyer had to be sought. The gem, also, had to be secured, in case the Tibetans actually put into action their vengeful methods. "Toby was working here. Ryder thought it a clever plan to have this former aide help him, and so he concealed the gem and had it innocently delivered here, but Toby, not as dumb as he was considered, suspected the truth, discovered the hidden gem, and on his own hook offered to sell it to a buyer he had known at Clark's store. "That made it necessary for Ryder to recover the gem quickly from the concealment no longer unsuspected here. He tried to get people away from upstairs, by detonating with his foot a torpedo under our office desk; but Astrovox, our scientific star-student, had been about to go home, frightened by some foolish combination of star-positions and a manifestation planned to scare him away. He walked in before Ryder could hide, recognized him--and the desperate man struck him. "Soon thereafter he realized that in a list of some fifteen sounds made by Roger there lay the actual clue that incriminated him and no one else!" "What was it?" asked Ellison anxiously or eagerly, Roger told himself. "What Roger thought was claws-on-glass. His very first sound-clue. With that on a list, and in the clever head of the stock-room clerk, Ryder had two things to do quickly. He must get the gem, and he must either find a way to throw suspicion elsewhere or get Roger out of the way." Roger realized why many attempts had been made, like the one in the dark-room. "I warned Roger. Ryder, when Toby--who knew where the gem was--telephoned him that he had left explosives out in the open--Ryder tried to use that as a way to lure Roger here to open up, because we had so arranged things that actually no one could even enter and not be caught--he was deadly afraid of being electrocuted too soon. "But Roger is still safe, the gem is available, and so--as you well know, there is no more mystery, except this: "How do you think you are going to get the Eye of Om--now?" Roger stared at his cousin. Saying that. To a beast! Chapter 41 MAN AND BEAST With his mocking smile Grover walked over to their safety cabinets, unlocked and threw one wide open. Roger, with Potts, sidled over near the door, to block the beast if it had been taught to snatch anything in its paws and hop away. "No need," Grover laughed, "with its partner, the ape, bound. There is no way to get out of that hide." He gestured toward the cabinet. "There it is, just as you hid it, the True Eye, in a can supposed to contain medicating compounds to use on the rats. Clever, just as was entry into Roger's room, with the 'Fire' record, by that often-used idea of the pulled fuse. I have wondered why you did nothing to him. Or did Millman come along too soon and scare you off?" He paused, and they all stared. Could Grover have miscalculated, Roger wondered, in implying that the kangaroo was the impersonator? He had assumed it was the ape. The beast, on its haunches and flatly extended tail, reached two clawed paws upward, caught one of the round cans from the front row, and dropping it in the loose pouch, in the skin, turned and started hopping toward the door, its claws upraised. Grover, as it moved toward the chair occupied by the ape, deftly caught its tail and swung an end around a chair leg. "Shall I turn on the current?" he chuckled. The animal became quiet, stopped. Once only he tried to escape and when Potts made a move to obstruct the way Grover calmly waved him back. "But he's got the can, Grover!" Roger also stepped forward. Grover actually grinned at them. "Let him go," Grover waved back Potts and Roger as the thing began to hop toward them and they made preparations to try to stop it. "The Doctor," went on Grover as the animal paused an instant, "to get Toby where his word would not be trusted, to remove him from the laboratory before he could take away the gem he knew about, planned his own poisoning this morning. He sent Toby for a drink, and by swallowing some quick-acting sedative, perhaps strong codein, or another of the poppy derivatives, he seemed to be poisoned. To make it appear like strychnine or some other--wait! I'll venture to assert that in the other room Roger will find the shell of some pit such as you crack in a peach and extract a tiny kernel. Those inner kernels of a peach pit, chewed up, would leave on his breath just the same odor as a very dangerous poison which I shan't name." Later that was verified. Roger found the cracked peach pit. "It was easy to 'recover' and come here tonight," Grover ended. He stood, looking with a mocking smile at the crouched beast and the bound animal. The latter, quiet for a moment, growled deeply. "The ape, trained at a certain point, to unfasten the kangaroo-skin so that Doctor Ryder can wriggle out of it, can't help," he remarked. "Oh, yes," to Millman's question, "the ape is genuine, a well trained animal. The kangaroo--shall we help him?" He walked over, and with a quick motion pointing out the laced arrangement of eyelets under an armpit--or forepaw--he dragged the lacing apart. Revealed, it was seen by all that Doctor Ryder actually was in the skin, crouched down as the size of the animal compelled him to be so that he could barely get his forearms into the front paws. The head, too small to hold his own cranium, was fixed almost in one position by supports, and eye-holes were cut lower in the skin, well concealed by the way the skin of the chest was sewed and the animal hair arranged. "He rented it from the animal trainer, who sometimes put it on, and played the part of his own animal in the act if the kangaroo became too fractious or when it was ill in our varied climate as they travelled from theatre to theatre." Cramped, scowling, Doctor Ryder emerged. "Very cleverly worked out," he growled. "Yes, it is all true. I did plan to have your laboratory staff help me steal the Eye, just the way you have it worked out. And if it had not been for Roger, almost at the beginning thinking of developing a sound-film I had neglected to put out of commission, you might not have found out." "Probably we never would," Grover agreed, and as bluecoats came tramping up the stairs, with a man who went at once to his animal, and with soothing words quieted it, released and removed it, the Tibetan lama and his cohorts came in. "But what _was_ the sound-clue?" asked Millman, "the fire-cry on a record supposed to be unused? I got that, you know. But it meant only a prank of Roger's to me." "Neither that, which revealed how the Balsa-wood was connected up, nor the Voice of Doom, made by Ryder, here, but not traceable to him alone; nor the click as he switched on the motor; nor the clicks as his trained thief's fingers manipulated our safe; nor the rest." "Well, what _did_ the sound that Roger described as claws on glass really signify that linked up Ryder and not any of us?" asked Zendt. The pseudo-physician, scowling, was twirling his watch-charm with nervous fingers as he watched the Tibetans who scowled at him. "He is showing you," Grover remarked. "Don't you see?" Roger turned to Millman. "I got the right idea only just tonight." "The watch-chain? But----" "You, Mr. Millman, and Mr. Ellison, were on the ground floor when the man came down because he had seen the rich man arrive in his car, and knew Toby had played false to him," Grover stated. "Think," Roger hinted, "he twitched and twirled that charm so it flicked light from the gold, the way a heliograph does." "That, when Roger told me, connected him with the first sound-clue of the scratching, hissing, clicking sound at first claimed to be a snake, then supposed to be his kangaroo." "Don't you see," interposed Tip, who was improving, by leaving out the big words, "he had to bend over to get the rats out of the trap on top of the cage. He brought the ape to unlace his disguise. And his watch chain and charm scraped and rattled and slid on the cage, and our sound-camera film got the sound from the microphone inside the cage." "Of course--and no one else wears a chain and charm," agreed Zendt, "we all have wrist-watches." "Well, what's the use of holding me for all this?" growled the man by the skin. He picked it up. "I'll just return this--go on and arrest me if you have any charge you can support with evidence that a clever lawyer can't break down," snarled the man. "A sound record, through your own Balsa-wood device, and down to our recorder, will do the trick," Grover smiled. "Made by you, just now, when you admitted all my previously recorded accusations." "All right. I'm licked. Good night, all." He turned as if to give himself up to a policeman. "He's got the Eye, in with that compound!" cried Roger, as Toby pointed at the pouch in the Kangaroo skin. "Oh, no he hasn't," Grover actually chuckled in triumph, "in the same way that he substituted the prepared can of film for a blank strip when he handed Roger the can to load the magazine--so his animal ghosts would seem to appear on an unexposed film when developed, I substituted a can of oxygen, hydrogen, nitrogen and a trace of ozone, perhaps, and a few other gases----" "Air?" gasped Ryder, shaking the can taken from the skin. "A free sample of air that is no longer contaminated by the gas Roger so cleverly used to drive you out--a ruse that enabled me to get here before you could return in disguise." The man was defeated. He was allowed to remain only long enough to make Grover's triumph complete by sending Roger to the cabinet to take down the can just behind the place from which he had removed his false one. Therefrom, the Tibetans were glad to receive, as they forgot all animosity toward Roger, the true Eye of Om. For his attempts on Roger's safety and his act toward Astrovox, Ryder stayed behind bars a long time. Chapter 42 CLOSING TIME The Ear Detective, more favored than ever because he had been the means of listing sound-clues, one of which had completely linked Ryder into his crime, was busy. Astrovox, well recovered from his blow on the temple, was going to "shoot" the stars as they crossed over the lens of his telescope and Roger was getting a sound-film into a camera. "Why in the world did Ryder have to go to all that trouble?" the old star-reader inquired. "How much simpler to have come in his own clothes. More freedom for his hands, that way, and no need to bring the ape to unlace his animal skin." "He knew," Roger explained, "about out protective device, and by wearing the skin and bringing the dancing ape, he would never be photographed and he would fool us all the more." "Well," remarked Astrovox, "you'll remember that Neptune--the planet of deception--was opposed by Saturn, the planet of obstruction, and there was an opposition of Mars, ruling explosives, with Uranus, which is, you might say, the planet that brings up the unexpected." Roger smiled to himself. Good old Astrovox, he mused, with his oppositions and "aspects" and all, was, still, a very clever scientist, and must be humored. "Yes," he chuckled, "and if I remember all you told me, something like this was in the 'horoscope' that day. The 'sixth house' has to do with animals--smaller animals, and Neptune with larger ones." "That is my astrological teaching." "Well, Neptune is in that sixth house, and if Saturn is the planet of obstruction it shows why the false doctor in his deceptive disguises, would be obstructed or caught." "Rats!" Tip snapped. "Rats are under the sixth house," Astrovox seriously persisted in apparently preposterous ideas, "and Neptune showed how the gas was used and also how the acid test, when Grover applied it to the shoes Ryder had worn, revealed in the paraffin cast the exploded gas of the torpedo he had stepped on to attract attention just when I ran in and recognized him." "What explains _my_ denseness?" Grover arrived, with a special quartz lens for some prism-and-spectroscope color work, "I was put off the track at first because Ryder knew my favorite axiom, 'dig past appearances that can be falsified, to find truth which is ever the same.' He deliberately hid the culture tubes in his own racks, and I fell into his trap, trusting him, thinking he was being victimized by some one else. It made it possible for him to be here, operate the trick with the Voice of Doom and hand Roger the prepared film supposed to be unexposed, carrying his animal pictures that he took at a special performance given him for good pay by the animal trainer." "Your density was because Mercury was in the twelfth house, and squared the moon in the third--wrong deductions." "Maybe those 'houses' are true," chuckled Grover, "I know one house _I_ am going to occupy. My own home. For a good sleep. How about you, Roger?" "After I see that all our apparatus is fixed for the night." "You go ahead," Potts grinned fondly at his chum, all suspicions forgiven, "I'll see that everything er--uh--coagulates!" THE END The Mystery of the 15 Sounds _By Van Powell_ When Roger's uncle offered him an opportunity to help in his scientific laboratory while the boy's parents were in Europe, Roger jumped at the chance. His uncle's laboratory--one of the most perfectly equipped--was the most fascinating place in the world. Even the latest scientific devices, however, could not keep out the "Voice of Doom" which sounded hollowly through the laboratories in the dead of night, or prevent the ghostly antics of the phantom kangaroo and his ape-like companion. These and many other occurrences make THE MYSTERY OF THE 15 SOUNDS one of the best boys' mystery stories of the year. _Books for Boys_ In selecting the books of this series we, as publishers, have tried to present a varied assortment, which will stir the imaginations of all boys. At the same time we have kept these stories from being nerve-wreckers. Herman M. Appel Secret of the Flambeau, The. William Dixon Bell Sacred Scimiter, The. Moon Colony, The. Secret of Tibet, The. Walter Butts, Jr. Brothers of the Senecas. Graham M. Dean Agent Nine and the Jewel Mystery. Agent Nine Solves His First Case. Circle 4 Patrol. Daring Wings. Herb Kent, West Point Cadet. Herb Kent, West Point Full Back. Slim Evans and His Horse "Lightning." Treasure Hunt of the S-18. Edwin Green Air Monster. Secret Flight. William Heyliger Big Leaguer. Detectives, Inc. Fighting Blood. Loser's End, The. Norton H. Jonathan Dan Hyland, Police Reporter. Gilbert A. Lathrop Whispering Rails. Mystery Rides the Rails. George Morse Circus Dan. Extra. Vanishing Liner. John A. Moroso Nobody's Buddy. Ambrose Newcomb Eagles of the Sky. Flying the Coast Sky Ways. Sky Detectives. Trackers of the Fog Pack. Van Powell Mystery of the 15 Sounds. Warren F. Robinson "G" Man's Son, The. "G" Man's Son, at Porpoise Island. Phantom Whale, The. Lieut. Noel Sainsbury Bill Bolton and the Flying Fish. Bill Bolton, Flying Midshipman. Bill Bolton and Hidden Danger. Bill Bolton and Winged Cartwheels. Harold M. Sherman Captain of the Eleven. Down the Ice. Interference. In Wrong Right. It's A Pass. Over the Line. Strike Him Out. Tahara, Among African Tribes. Tahara, Boy King of the Desert. Tahara, Boy Mystic of India. Tahara, in the Land of Yucatan. Under the Basket. Wayne Whipple Young Abraham Lincoln. Young Franklin Roosevelt. THE GOLDSMITH PUBLISHING CO. CHICAGO, ILL. Transcriber's Notes --Copyright notice provided as in the original--this e-text is public domain in the country of publication. --Silently corrected palpable typos; left non-standard spellings and dialect unchanged. --In the text versions, delimited italics text in _underscores_ (the HTML version reproduces the font form of the printed book.) End of Project Gutenberg's The Mystery of the Fifteen Sounds, by Van Powell *** END OF THE PROJECT GUTENBERG EBOOK 53214 ***