Signal in the Dark

by Mildred A. Wirt

  CHAPTER 18 _A SECOND TEST_

  As Penny knelt beside Salt, he stirred slightly and raised a hand to hishead. She saw then that there was a tiny break in the skin which also wasslightly discolored. Either the photographer had fallen or he had beenslugged.

  Before she could go for help, he sat up, staring at her in a bewilderedmanner. Penny assisted him to a chair, and dampening a handkerchief withwater from the tap above the developer trays, applied it to his forehead.

  "What happened?" she inquired anxiously when Salt seemed able to speak.

  "Slugged," he answered in disgust.

  "By whom?"

  "Don't know. The fellow must have been in the darkroom when I came hereto develop my films. Fact is, I thought I heard someone moving around. Istepped to the door to see, and bing! That's the last I knew."

  "Has anything been taken, I wonder?" Switching on another light, Pennyglanced over the room. The drawer of a filing cabinet where old films,and plates were kept, remained open.

  "Someone may have been looking in there!" she commented. "Salt, whoeverhe is, he must be searching for a film he is afraid we'll publish in thepaper."

  "Maybe so," Salt agreed, holding a hand to his throbbing forehead. "But Idon't know of any picture we have that would damage anyone."

  Penny stepped to the doorway of the darkroom. In the larger room, theskylight remained closed. It was impossible to tell if anyone had enteredthe building in that way.

  Some distance down the hall was a seldom-used stairway which led to theroof. Finding a door opening into it, Penny climbed the steps to lookabout. The rooftop was deserted, but in the building directly across fromthe _Star_, a corridor window remained open.

  "How easy it would be for a man to step out onto the roof from there,"she thought. "If the skylight or the stairway door were unlocked, heeasily could enter the _Star_ photography room without being seen."

  Across the way, in the adjoining building, a man stood at an officewindow, watching Penny curiously. Sun glared on the panes so his face wasdistorted. But from the location of the window, she felt certain it wasMr. Cordell.

  After a moment, Penny turned and went back down the stairs. The exit atits base was barred by a door with a rusty key in the lock.

  Passing through, Penny locked it, and slipped the key into her purse.

  "That should stop our prowler for a few days," she thought.

  In the photography room again, she checked the skylight, and finding itlocked, was convinced that this time the mysterious visitor had enteredthe building by means of the stairs. She knew the door was usually keptlocked, but undoubtedly the janitor had been careless.

  By this time Salt was feeling much better. While Penny waited, heexplained to the editor why the photos would not be ready until morning,then declared he was ready to start for Blue Hole Lake.

  "Do you really feel like going?" Penny asked dubiously.

  "Sure thing," the photographer insisted. "It takes more than a little tapon the head to put me out of running."

  Salt walked a trifle unsteadily as they went down the back stairstogether, but once they were in the press car, he seemed his usual jovialself.

  "Now tell me about that plan of yours for tonight," Penny urged as theyjounced along the country road.

  "It's not much of a plan," the photographer confessed ruefully. "First,we've got to learn exactly what Webb does to those mines to make themexplode. Then somehow we'll have to undo the work to cause thedemonstration to turn out a flop."

  "It sounds like a big order," Penny sighed. "We'll need plenty of luck tocarry it out. Especially as we're arriving rather late."

  Having no intention of announcing their presence, the pair drew up abouta quarter of a mile from the lake, parking in a side road.

  Shadows were casting long arms over the ground as they started hurriedlyacross the fields toward the beach. They had covered two thirds of thedistance when Penny suddenly caught Salt's arm, pointing toward the lake.

  "Look!" she exclaimed. "There they are now!"

  Out on the lake a barge-type boat was being steered toward the beach nearthe shack where Professor Bettenridge stored the mines. The watchingcouple recognized three persons aboard the craft, the professor, Mr.Johnson and Webb. The barge also bore a large mine, similar in type tothose Penny had seen inside the shack.

  "That must be the mine Mr. Johnson is supplying for the test tonight,"she whispered.

  Hand in hand, Penny and Salt crept closer to the shore. The boat gratedon the sand and Webb, with the professor helping him, carried the heavymine toward the building.

  "If the mine is to be exploded tonight, wouldn't it be easier to leave iton the barge ready to drop into the lake?" Penny commented. "Webb and theprofessor must have a special reason for hauling it ashore."

  "I think you have something there," Salt observed. "Obviously, they'regoing to doctor it in some way. We'll see what happens."

  Webb unlocked the door of the shack and the two men carried the mineinside. Creeping still closer to the building, Salt and Penny heard Mr.Johnson say:

  "Just a minute. I see you have other mines stored here. How am I to besure that the one exploded will be the mine I have provided?"

  "You may mark it if you wish," the professor replied. "In fact, we preferthat you do, so there can be no possible doubt in your mind. Take thispocket knife and scratch your initials on the covering of the mine. Thentonight, before it is dumped in the lake, you may check again to seethere has been no substitution."

  "You understand, I don't distrust you," Mr. Johnson said, ill at ease."But so much money is at stake--"

  "I understand your attitude perfectly," the professor replied. "Certainlyyou are entitled to take every precaution."

  A silence ensued, and Penny and Salt assumed that Mr. Johnson wasscratching his initials on the mine.

  "Now suppose we have dinner at the village inn," the professor presentlysuggested. "Then we will have the demonstration."

  "Must we wait so long before setting off the mine?" Mr. Johnson inquired.

  "Yes, village authorities gave permission for the test to be held at nineo'clock," the professor explained. "My own preference would be to get itover immediately, but I dare not disobey their orders."

  Mr. Johnson made no reply, and a few minutes later, the three men walkedaway. No sooner had they disappeared up the lake than Penny and Salt cameout of hiding from among the trees.

  "You have to hand it to Professor Bettenridge," commented thephotographer with grudging praise. "He's a smooth talker. I'll bet afrosted cookie the test could be held at one time as well as another sofar as the village authorities are concerned. He has a special reason forwanting it at nine o'clock."

  "Probably to give Webb time enough to work on the mine or exchange them,"Penny said, and then frowned thoughtfully. "But what if the machineactually should work? After all, the professor agreed to explode Mr.Johnson's mine, and apparently he's marked it with his initials. It won'tbe easy to substitute another one now."

  "All the same, if I'm any good at guessing, it will be done. Now whatshall we do until nine o'clock? Grab ourselves something to eat?"

  Penny was about to suggest that they drive to a village cafe, when shenoticed Webb returning alone from up the beach. Barely did the pair havetime to duck out of sight behind a boulder before he approached.

  Walking directly to the shack, he unlocked the door, and entered.

  "Now this must be where the hocus-pocus begins!" Salt whispered. "We'vegot to find out what he does to that mine."

  "Louise and I climbed up in that tree the other day and looked throughthe glass in the top."

  "Then that's the trick for us! Come on!"

  Making no sound, the pair climbed the tree close beside the shack.Noiselessly, they inched their way toward the skylight, and lying flat,peered down into the dark interior.

  Webb had lighted a lantern which h
e hung on a wall nail. Unaware that hewas being watched, he squatted in front of the mine which bore Mr.Johnson's initials, studying it thoughtfully.

  Muttering to himself, he next took a powerful ratchet drill, and for along time worked with it on the mine, boring a tiny but deep hole.

  "I'm getting stiff in this position," Penny whispered. "What is he doing,Salt?"

  "Don't know," the photographer admitted, puzzled. "Apparently, he'sdoctoring Mr. Johnson's mine so it will explode tonight, but I'm notsmart enough to figure how the trick will be accomplished."

  By now it was so dark that the pair in the tree no longer feared theywould be seen. Keeping perfectly still, they watched the work in the roombelow.

  "It's clear why Professor Bettenridge set nine o'clock for thedemonstration," Salt whispered. "Webb needed all this time to get themine ready."

  "And that's why they brought it here instead of dumping it into thelake," Penny added. "But how can they make the mine explode at exactlythe right moment?"

  After Webb had worked for a while longer, he arose and stretched hiscramped muscles. Going to a cupboard, he removed a white powder from aglass tube, and carefully inserted it in the hole he had just made in themine. As a final act, he sealed the tiny hole with another material, andpolished the surface so that the place did not show.

  "Slick work!" Salt commented. "By the time he's through, no one evercould tell the mine has been touched! Certainly not that thick-skulledJohnson."

  Apparently satisfied with his work, Webb put away his tools, made a finalinspection of the mine, and then left the shack. After carefully lockingthe door, he disappeared into the night.

  "Now what's our move?" Penny asked as she and Salt finally slid down fromtheir uncomfortable perch. "Shall we tell Mr. Johnson what we just saw?"

  "We could, but he might not believe us. Penny, I have a better idea! Ifwe can get inside the shack--"

  "But it's locked!"

  "The skylight may be open." Salt climbed up on the roof to investigate,but to his disappointment, the roof window was tightly fastened frominside.

  "We could smash the glass," Penny suggested dubiously.

  Salt shook his head. "That would give the whole thing away. No, I thinkwe can get inside another way, but we'll have to work fast! Now that Webbhas the mine ready for the demonstration, the professor and Mr. Johnsonmay show up here at any minute."