by Van Powell
Chapter 3 A "SOUND" CLUE
Without waiting for the gelatin to harden, Roger summoned the staff andhis cousin to the screening room. As soon as they had set their wristwatches with the observatory time signals, a routine part of the staff'saccuracy, they joined him.
He had the tender emulsion-covered celluloid threaded from the topmagazine through film gate and take-up sprockets down to the lowermagazine of the projector. In the small, compact theatre, with itsplatform for lecture and demonstration procedure, its large screen, easychairs, loud speakers and apparatus, he showed Grover and the men whatcaused 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 footedcreatures, he explained, did not disturb dust at the point indicated inclose-up and wide-angle pictures, greatly enlarged by the projector.
The chief electrical specialist, Mr. Ellison, agreed. "It ends themystery. A snake ate the rats."
"Then there won't be any disease epidemic," Doctor Ryder was muchrelieved, "It will crawl somewhere and the germs may destroy thereptile." 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 goforward, and the staff men separated. Zendt went to resume experimentsin the search for a dye of a certain desired shade and quality: the twoelectrical men were busy developing means to find a better way toinsulate high-tension cable for carrying electricity from generators todistributing stations in small communities; the others had equallyabsorbing work in progress.
Grover, busy examining each picture projected and held on the screenwithout danger of the "cold" light igniting the protected film, gaveRoger 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 thestiff rusted bolt inside the trapdoor of the coal chute, a trap thatlifted 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 tosecure most perfect focus, made his exposures, developed, and fixed thelarge 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 hisstatement; but his disappointed eyes told Roger that the examination hehad made during developing work had been accurate, thorough, and had ledto a correct decision.
They were at a standstill. Calls to the zoo, brought from its curatorthe declaration that no snake was absent from its cage, that no one ofhis keepers had tried to "train" snakes--as the laboratory head hadhalf-laughingly suggested.
As he left the screening room, Roger met Potts.
"Tip," he hailed, "Did you get anything on the 'sound' film in theone-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 ofpeaks an' valleys on the sound track."
"You always will use a .44 caliber word when a BB. size would hit whatyou 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 showedany 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 theseismograph-like recorder; and it seemed as though the 'continuous'taking lever had been shifted before he--it--whatever was there, stoppedthe whole business by breaking off the wiring."
"We can try."
When they had developed the negative, made a print and fixed and washedit, Roger threaded the fifteen frames of continuous shots in place andprojected 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 amplifiedwith transformer-coupled, matched metal audio tubes of the most perfecttype giving the speakers power, they had picked up a sound of hot greasesputtering, hissing and clicking, as it does if sausage is friedrapidly.
"Come on, Ear Detective," chaffed Mr. Millman, "Who was frizzlingsausages on the cage full of inoculated rats, so that the mike insidepicked it up and took it on to the sound film?"
"That's not sausage frying," exclaimed the biochemist, "Someone hadsteam up and the mike picked up the sound the radiator valve made as airwas expelled and steam arrived to close it spasmodically."
"A microphone, inside of a glass cage top?" mocked Mr. Ellison. "Howcould 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," headmitted, "But----"
"It's a snake, I say," Potts defended his theory; "a snake, with hissingand his scales rattling on the glass when he was crawling up to dig hishead 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 youngperson able to read correctly what his sensitive ears caught; Roger wasnot vain or self-satisfied. He was not the sort to make a statement justto hold up his reputation.
In some ways the sound might be such as a snake, with its hide strikingor rubbing, as it hissed, could make; but, again, a lizard might makethat 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 allthat had so far happened.
Never in his stay at home or laboratory, intimately close to thescientifically brilliant, but poised, cousin, had Roger seen him losehis calm.
Now, Grover stood up, and in his eyes was the same sort of light ofsatisfaction and triumph that a boy would show when he had successfullysmuggled 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 hisdeductive ability. He paused.
"I will leave you to work it out," Grover beckoned to Roger; "I must runout to the zoo." He was as eager and elated as a boy with a newfootball.
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 backissues for the past two weeks, maybe you'd better get them for threeweeks 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 thetruth. Mars
hal your facts, test each one, eliminate the impossible andwhat you have left is the truth."
Telephoning to summon a taxi for Roger, the laboratory head was busy fora 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'sclever mind had skipped many of the links that Roger, slowly, had totake up and examine.
He was in the taxi, with bundles of back issues of the city papers, onhis way back, and still his mind was a maze of unfitted details.
In the office, combing the papers for notes about snakes, or any otherescaped reptile--he had to keep in mind that trail on the edge of thesteps alone!--he got nowhere.
No news showed up about lost, stolen or escaped animals or any form ofbrute or reptile.
Grover, he saw, had returned, and was not joyful.
"One theory went to smash," he said, "I verified your sound--claws onglass 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 screenimages carefully. The cellar views, only proving that some object leftno other trace of progress than scraped dust on step-edges, heconsidered and discarded.
Those taken by windows, doors, intakes and outlets of theair-conditioning, and gas-exhausting roof, cellar and wall orifices gaveno revealing clues.
When he got to the wide-angles of the lower floor and stairway, andfound no reward for his long scrutiny, Roger was baffled.
Only the micrometric enlarged snaps and one time-exposure near the X-raydevices remained. He considered them ruefully. They gave no foregroundevidence 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, butat the more important quality of being able to connect the clue witheverything 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 hadaccumulated 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 racedto find Grover.
"Just by chance, in taking the micro-lens pictures," he gasped out, "Tipgot 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 inrevising our arrangement of the racks. Go on!"
"The tubes that held the culture of the spinal disease germs--sodangerous that they had been delivered, personally, by the medicalcenter 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 preventinfection."
"So did I." Grover acknowledged the fact.
"He actually took two tubes that must have had the right labels becausehe 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 usethe hypodermic needle."
"But--" Roger could hardly restrain his thrill at having made as clevera discovery as the coming one:
"Those two tubes--full!--are in back of others, right now. Not the twoempty 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 adarkish gray; and our culture labels, that are a buff, photographlighter, but still grayer than white paper. The poisons are labeled redand come out in a picture almost black.
"_But blue except very dark shades, will photograph nearly white!_ Andthose two labels, hidden in a dark corner, show up in the picture wherethey 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 dangerousto him."
"Very nicely argued out, Roger," his cousin complimented him. "Now, wemust find a way to draw that criminal who trains animals to do his work,into the open where police can get him."