The Disappearing Floor Read online

  The prisoner had an angry look, like that of a trapped animal. “I told you it doesn’t matter!” he retorted. “I know what you boys are up to! You’re trying to worm information out of me, hoping you can get all the stones for yourselves!”

  “Now listen,” Frank snapped, “I don’t know what you mean by that remark, but you’d better talk fast or we’ll call the police! I think we should, anyhow.”

  “No, no! Please!” The prisoner seemed to crumble. “I can’t afford to go to jail now—there’s so much to do! I can explain. I’ll tell you whatever you want to know.”

  “You can begin by answering Joe’s question—and then tell us why you’ve been prowling around in that spook getup.”

  “All right.” The man gulped and tried to pull himself together. “My name is Karl Nyland Jr. Years ago, my father discovered an amethyst lode somewhere near Bayport. He went to old Jerome Perth for financial backing—they even signed a partnership agreement. But that swindler, Perth, double-crossed him!”

  “How so?” Frank asked.

  “Perth bought the site in his own name, then kept stalling my father off—said he was waiting for a geologist’s report. Finally my father got fed up. They quarreled and Perth had my father thrown out of the mansion. But first Perth taunted him. He said the partnership papers, and some amethysts my father had brought him, were kept in a place outside the mansion where anyone could get at them—but my father wouldn’t be smart enough to find it.”

  “Boy! Sounds as if Perth was a real snake in the grass!” Tony muttered.

  “That man was evil,” Nyland declared, “but he got his just desserts. The quarrel brought on a heart attack and he died the next day.”

  “Didn’t the partnership papers turn up when the old man’s estate was settled?” Frank asked.

  “No, his lawyers claimed that no such papers, nor the amethysts, were among Perth’s effects. My father kept searching secretly for a long time after that, but he never could find the hiding place.”

  Joe snapped his fingers. “He must have been the ghostly figure that people thought was haunting this place!”

  “Yes, he was searching here the night the nephew died,” Nyland admitted. “That’s what gave him the idea of dressing as a ghost. He thought it might help to scare tenants away and keep the mansion unoccupied until he could locate the secret cache. But he never found it.”

  “At least his scheme to scare people away worked,” Chet put in. “And now you’ve been trying the same stunt?”

  Nyland nodded guiltily. “I received a bad electrical shock when I was searching here the other night. That’s when you boys found me unconscious. Since you’d seen my face, I decided I’d better use a ghost costume as a disguise, in case you came back to look for me.”

  “How come you waited so long to begin searching?” Joe inquired.

  “I was a child living with relatives in another state when Perth swindled my father,” Nyland explained. “It was only recently that I ran across my father’s diary and read the whole story. My wife’s been very ill, and I was in debt from the hospital bills—so I decided to come to Bayport and try to find the lode and the partnership papers.”

  “Sounds like a wild-goose chase,” Frank said.

  The man nodded. “That’s just what it’s been. All I have to show are these.” The man reached into his pocket and pulled out a dozen small metal disks. Each bore a picture of a violet above a dragon’s head I

  “Perth’s lucky pieces!” Joe exclaimed. “We found one near the mansion—you must have dropped it there!”

  “Could be,” Nyland admitted.

  “Do you know what the design was supposed to signify?” Frank asked.

  “Not really,” Nyland said, then added ruefully, “To me, the dragon is Perth—and the violet’s a symbol of the lovely purple stones he tricked my father out of.”

  Joe frowned. “Was there only one copy of the partnership agreement?”

  “Exactly. Perth was sly about that. My father foolishly trusted him and didn’t insist on two copies being drawn up.”

  “Then why wouldn’t Perth simply destroy the agreement when the deed was in his name?”

  “He was using it to soft-soap my father and keep him quiet—also to keep him on a string. You see, my father had made two earlier gem strikes for a mining company. Perth no doubt hoped he might make other valuable finds. And I’m sure Perth was cruel enough to keep the agreement after their quarrel—just to tantalize and torment my father.”

  “You have no idea where the amethyst lode was located?” Joe asked.

  Nyland shook his head dejectedly. “No, Perth owned a great deal of property, but it was all sold off after his death. And the diary didn’t say. That’s why I shadowed those two girls after I overhead them telling the gem-shop proprietor about finding a large amethyst. I hoped they might lead me to the lode.”

  “What were you doing aboard that cruiser tonight?” Tony inquired.

  Nyland shrugged. “Just a hunch. There’s something strange about those people living at the mansion now. This afternoon I saw two of them in town and heard them mention the word ‘amethyst.’ I thought maybe they had found the papers relating to the lode, so I shadowed one of them. He went to that boat, and after he left, I climbed aboard myself. But it was a waste of time—I found nothing.”

  Nyland’s shoulders sagged. Half sobbing, he began to tell the boys about his wife’s illness and the debts that had made him desperate. He pleaded with them not to turn him over to the police. The Hardys, Chet, and Tony felt perplexed and embarrassed. They decided to leave the decision to Mr. Hardy.

  Suddenly a light went on in an upstairs window of the mansion. Joe exclaimed, “It’s the window where we spotted that man who looked like Professor Darrow! Frank, let’s stay here—we may see him again!”

  Frank glanced at Chet and Tony. “Dad’s due in tonight. Would you two take Nyland to our house and keep him there till Dad arrives?”

  “Sure. I can call my folks,” Tony replied.

  “Same here. And maybe your Aunt Gertrude will make us all a snack,” Chet said hopefully.

  Nyland, anxious to avoid arrest, agreed to accompany them with his hands tied and to make no trouble. All three went off in Chet’s car.

  “The man’s odd, but I think he was telling the truth,” Frank said. “He sure sounds as if he’s been under a nervous strain.”

  The Hardys started back up the slope. Cautiously they began making their way through the wooded grounds toward the mansion.

  Suddenly there was a weird scream from close by—then another, weaker scream, ending in the same gasped-out words they had heard before:

  “Th-th-the floor!”

  Frank and Joe froze. “It’s only a trick,” Frank muttered as they started forward again.

  They were nearing the house when both boys went cold with shock. A glowing white figure had risen from the ground!

  “We caught the spook already,” Joe whispered.

  “It’s a fake, Joe.... It must be a fake!” Frank stared in horrified fascination.

  The thing was moving toward them, flapping!

  Resisting an impulse to run, the Hardys closed in. They clutched at the specter. Joe gave a chuckle of relief as he felt the wire framework underneath. It was covered with some kind of synthetic cloth, which evidently had been dipped in white phosphorescent dye.

  “Just a pop-up scarecrow, Frank! We must have stepped on the release mechanism back there.”

  “Right, Joe. And look at the wheels. The breeze blew it toward us!”

  They went on. In the shadow of a tree they paused and looked up at the lighted window. Shelves with bottles and test tubes, and some electrical apparatus, could be seen.

  “A laboratory!” Joe murmured.

  Behind the shaded windows on the ground floor a radio was blaring dance music.

  Suddenly a man moved into view at the upper-floor window. Bald and bespectacled, he was holding an open book in one hand.
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  “There he is!” Frank whispered.

  “That’s Darrow, all right,” Joe agreed. “If only we could talk to him!”

  “Fat chance with Strang and his gang around. Anyhow, we’ve seen all we need to. Let’s go home and wait for Dad.”

  Turning, the brothers started back across the grounds to their car. Halfway down the slope, they heard the screams and the choking voice again.

  “Hold it, Joe,” Frank hissed. “That tiled floor’s around here somewhere. Did you notice that we always hear the screams near here?”

  The boys shone their flashlights carefully about the ground. Suddenly Joe’s beam disclosed a small metal object sticking up from the grass.

  “I’ll bet that’s it, Frank! Must be some kind of sensor—maybe infrared—that triggers off a tape recording when anyone comes near.”

  Joe moved closer to examine it. Again the voice shrieked! Startled, Joe backed off hastily and his foot struck a rock.

  Frank gave a cry of dismay as the ground gave way under his feet. Down he plunged!

  “The tunnel exit!” Joe exclaimed. “My foot hit a rock—same thing that happened last night. That must be what opens it from the outside.”

  “Right. And look at all this sod and brush that fell in with me—they do camouflage the tiled floor.” Frank shone his flashlight into the tunnel. “Wonder if we could get into the house this way, past Strang and his henchmen, and talk to Professor Darrow?”

  Joe leaped down beside Frank. “I’m game! Let’s find out where the tunnel leads!”

  CHAPTER XVIII

  A Strange Machine

  FRANK had been only half serious when he spoke of trying to enter the house through the tunneL But Joe’s excitement communicated itself to him. This might be a chance to get information or a clue that would break the case!

  “Okay. Let’s take a look.”

  They started into the tunnel, one behind the other. Frank led the way, probing the darkness with the yellow beam of his flashlight.

  “Watch that intercom!” Joe warned. “We don’t want another chat with Waxie’s pal!”

  The brick-walled passageway went on for hundreds of feet. The boys came at last to a door. It had a lock but opened freely when Frank tried the knob. “It must unlock automatically when the tiled floor opens,” he whispered.

  “In that case, why the intercom?”

  Frank shrugged. “Someone might want to hide in the tunnel but still be able to communicate with the house. Or maybe they post a lookout at the tunnel exit sometimes and have him report back by phone.”

  The boys played their flashlights around. “We must be in the basement of the mansion,” Joe murmured.

  The huge, cement-floored area was dank and musty. There was a coalbin, a grimy-looking, cobwebbed furnace, and an air-conditioning unit that looked brand new. Far at the rear was a flight of stairs leading upward.

  Frank asked his brother, “Should we risk it? Or turn back?”

  “Don’t be silly! We’re going to talk to Professor Darrow, remember?”

  The boys walked cautiously toward the stairway and tiptoed up. They found that the first flight ended at the kitchen of the sprawling mansion. From here another flight led upward. The stairs creaked under the boys’ tread, but fortunately the radio music racketing in the ground-floor front rooms covered their noise.

  Reaching the upper floor, the boys went along a corridor toward the front of the house. The hallway twisted and turned as if the mansion had been designed with an eccentric floor plan. After passing several doors, the Hardys stopped at one which showed light underneath.

  “This must be the laboratory,” Frank whispered.

  Joe held up crossed fingers. “Okay. Let’s find out.”

  Frank opened the door. Professor Darrow was holding a test tube of colored liquid up to the light. He turned as the boys entered—and gave such a violent start that the liquid splashed on his workbench!

  “Professor Darrow—?” Frank inquired. Joe closed the door softly behind them.

  The scientist’s hand trembled as he placed the test tube in a rack. He stared at the Hardys through his steel-rimmed eyeglasses and his eyes were full of fear.

  “Who are you? What do you want?” he blurted out in a shrill, staccato voice.

  The muffled strains of the radio music could be heard through the floor.

  “We’re Frank and Joe Hardy, sir,” Frank began. “Our father is Fenton Hardy.”

  He assumed the name would be familiar to a crime-detection expert. But Darrow glared at them, giving no sign of recognition.

  “Fenton Hardy—the private investigator,” Joe emphasized. “Maybe you’ve heard of him.”

  “Maybe.” The scientist’s eyes bored through the boys. He wore a white lab coat and his wispy fringe of gray hair frothed out wildly around his narrow skull. “Why did you come here?”

  “Dean Gibbs of Western State asked us to locate you and—” Frank started to explain.

  “He would! You’ve come here to spy on me!”

  “That’s not true!” Frank exclaimed.

  “The dean wired us on behalf of your sister,” Joe put in hastily. “She’d like you to get in touch with her. She’s probably worried because she hasn’t heard from—”

  Joe broke off suddenly as he noticed the professor’s hand inching toward a strange device on his workbench. It looked somewhat like a round, portable electric heater.

  “Look out, Frank!”

  Joe leaped clear in the nick of time as Professor Darrow snatched up the device. But Frank did not react fast enough. A dazzle of light flared from the machine. Instantly Frank stiffened and froze statuelike.

  He had blacked out!

  An electric cord ran from the machine to a wall socket. Joe yanked the plug before Darrow could aim the device at him.

  “Help! Help!” the professor shouted.

  Joe glanced around frantically. The radio music from below had stopped. A moment later came the sound of feet pounding up the stairs!

  “Strang and his boys!” Joe thought. “I’ll have to duck fast! But where?”

  Suddenly Darrow lunged at him and tried to pin the boy’s arms. Joe wrenched free and gave the professor a hard shove that sent him reeling backward. Darrow crashed into a corner of the workbench and went down in a cascade of glass tubing, retorts, and other laboratory apparatus.

  Like a flash, Joe darted out through a doorway that led to an adjoining room. The door slammed behind him just as Strang and several henchmen came surging into the laboratory.

  “That way!” Darrow shrilled, pointing in the direction of Joe’s flight. “Through that door!”

  The gang rushed through a maze of connecting rooms. Joe, concealed behind the heavy, dark-red window drapes in the room next to the lab, could hear Strang barking out orders.

  A moment later the master jewel thief strode past Joe’s hiding place on his way back to the laboratory. Through the open doorway, Joe heard him talking to the professor.

  “Yes, I know the boy. Recognized him at once,” came Strang’s voice, evidently referring to Frank. “He and his brother are the sons of a clever spy who must have been sent to Bayport purposely to steal your invention.”

  “Just what I feared!” Darrow replied. “Then it’s not true that they’re connected in any way with Fenton Hardy?”

  “Certainly not! In fact, Hardy’s now on my payroll, working undercover to safeguard your research.” Strang’s voice became firm and persuasive. “Don’t worry, Professor! My men are bound to catch the other boy. Then we’ll hand them both over to the FBI.”

  “Frank, look out!” Joe yelled

  “I certainly hope you’re right!” Darrow sighed heavily. “First the university authorities and jealous colleagues blocked my research grant at school! And now spies hounding me!”

  “By the way,” Joe heard Strang ask, “how deeply did you black this kid out?”

  “Just a light dose. But it should hold him long enough to—”<
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  A loud alarm bell rang on the first floor, cutting short the professor’s words. Both Strang and Darrow dashed from the lab.

  Joe waited until he heard their steps fading down the stairs. Then he burst from the drapes and rushed into the laboratory. Frank was still rigid. Joe filled a beaker with cold water from the workbench sink faucet and flung it in his brother’s face. Frank seemed to shudder.

  “Frank! ... Frank, can you hear me?”

  Joe shook his brother and gave him several light slaps. Gradually Frank came out of the trance but appeared to have no recollection of what had happened. Joe explained hastily, adding, “Strang has the prof convinced that he’s surrounded by spies—including us. An alarm just went off downstairs, and they’ve gone to investigate.”

  Frank was still a bit dazed. “I must have been blacked out by the same device used in the jewel thefts, Joel”

  “Sure, and Darrow thinks we came to steal it. We must find a way out of this place!”

  “Wait a second, Joe! That alarm you mentioned could have been Dad coming here—maybe even the police!”

  “Right,” Joe agreed. From the sounds he had heard, he knew there must be a front stairway. The Hardys soon found it and strained to hear what was going on below.

  “Here they come now!”. Strang was saying. ”Looks as though they’ve nabbed whoever triggered the alarm!”

  Frank and Joe leaned around the corner of the stair well and peered down into the front hall. Strang was at the front door with Professor Darrow. Presently three of Strang’s henchmen came in, prodding a burly prisoner at the point of a gun. Their captive had crew-cut hair and wore a gaudy plaid sport coat.

  “Duke Makin!” Joe whispered in amazement.

  “No sign of that kid who got away, boss,” the gunman reported. “But we caught Makin here snooping around outside.”

  “Good work, Barney!” Strang said approvingly.

  “Barney’s the man who was with Jack Wayne at Tigers’ Bight!” Frank murmured in Joe’s ear.

  Duke Makin looked self-assured, which appeared to infuriate Strang.

  “I warned you once before, Makin, to keep out of my hair!” the jewel thief rasped.