The Secret of Skull Mountain

by Franklin W. Dixon

  They reread Frank’s brief message: “Going to Sweeper’s—”

  Why hadn’t Frank completed the message? Had he been in too much of a hurry? Or had he been interrupted? And why had he taken off his shoes and jacket?

  The two detectives looked out at the wind-whipped, murky water as if it held the answer.

  CHAPTER XI

  Cast Adrift

  WHEN FRANK swung the Sleuth out of the boathouse and roared after Sweeper’s speeding craft, he knew his mission was a tough one.

  “Can’t let him know he’s being followed,” the young detective cautioned himself.

  He guided his boat skillfully across Barmet Bay, skirting ships and smaller craft, going fast enough to keep Sweeper in sight without attracting his attention.

  The thin man’s speedboat headed out to sea. After half an hour Frank saw his quarry approaching rock-bound Merriam Island. Sweeper stowed his boat and disappeared behind a jutting finger of rocks. Frank cut his motor and let the Sleuth drift toward a tiny dock which extended from a narrow beach.

  He leaped out as his speedboat swung alongside the dock, and secured it. He saw no sign of activity in the lighthouse tower.

  “Guess the keeper’s asleep,” he muttered.

  Staying near the shore, Frank clambered over sharp rocks and ran along short stretches of sand toward the spot where he had seen Sweeper’s boat disappear.

  Cautiously he approached a cove and saw the craft rocking gently a short distance from land. Sweeper was pacing the beach and glancing frequently out to sea.

  “He must be waiting for someone,” Frank told himself. To watch the man, he stretched out on a smooth boulder, hidden from Sweeper’s view by a low shelf of rocks.

  Minutes ticked by. When an hour had passed, Frank saw that Sweeper was becoming impatient. The man paced the sand with short, jerky steps, stopping from time to time to glare at the sea. Finally he rolled up his trouser legs and waded toward his boat.

  At that instant came the put-put of a launch. It rounded the high rocks sheltering the cove and stopped well beyond the surf.

  The man at the wheel fumbled with something in his hands, and tossed a tin can into the water. He waved to Sweeper, pointed at the can, and swung the launch back toward Bayport.

  Frank, puzzled, watched the can dance on the waves. Then the surf caught it, and a white lip of foam hurled the container toward the beach.

  Sweeper waded out and plucked the can from the water. He pried open the lid and took out a slip of paper. After scanning it, he shook his head, crumpled the paper into a ball, and threw it into the ocean.

  The thin man waded to the speedboat, got in, and cast off. A few seconds later he eased his craft out of the cove and sent it roaring through the waves.

  Frank rose from his hiding place, ran to the sandy beach, and waded into the surf. He snatched the soggy ball of paper from the churning water. Returning to the beach, he unfolded the dripping sheet carefully. The typewritten message was still legible. It read:Meeting postponed until midnight tonight. Will meet you at buoy off Barmet light.

  Frank looked across the water. A hundred yards offshore a buoy bobbed. “That must be the one!” he thought, then glanced at his wrist watch. He still had time to return to Bayport and be back to spy on the meeting!

  “Wonder who sent Sweeper the message,” Frank mused as he made his way back to the Sleuth. He cast off the mooring line, climbed into the cockpit, and backed the sleek craft away from the dock.

  It was not long, however, before the Sleuth’s motor began to sputter. Frank looked quickly at the gas gauge and saw that the fuel was nearly gone. Instantly he headed back toward the island. The motor coughed into silence as the Sleuth swung alongside the dock.

  Frank tried to radio home for fuel, but found his short-wave set was dead. “What a break!” he muttered.

  After working over the equipment for several hours without success, he realized he would have to use the lighthouse radio.

  “No use attracting attention to my presence before the meeting here,” he decided. “I’ll contact the keeper afterward. It’ll be easier to spy on Sweeper’s boat if I swim out to it.”

  Frank sat in the cockpit and waited until red streaks of sunset flamed across the sky. Dusk fell and the island grew dark. Frank dozed.

  Suddenly he was jarred awake. A motor!

  Alert, Frank stared into the darkness in the direction of the sound. In the distance he saw the red and green running lights of an approaching speedboat.

  Frank noticed then that the time was twenty minutes to twelve. “Wow!” he exclaimed. “I’d better hurry!”

  He got a pencil and a scrap of paper and addressed a note to Joe and his father, in case they should trace him to Merriam Island.

  “Going to Sweeper’s—” Frank wrote hastily. At that moment the pencil point broke.

  Annoyed, Frank searched for another pencil, but gave up after a few moments and jammed the partly written message into the short-wave set.

  Swiftly Frank removed his jacket and shoes, then dived cleanly into the water and struck out for the buoy.

  The surf was rough and he gasped as the cold waves broke over his head. Settling into a steady crawl, Frank swam toward the blinking light on the buoy.

  After a hard swim, he reached it and grabbed hold of an iron chain which dipped deep into the water.

  Moments later the speedboat swung past the buoy, coming to a stop. A dinghy was tied behind it. Sweeper stepped to the speedboat’s deck and Frank could see that he was looking around.

  Watching the man, Frank swam quietly toward the dinghy. As Sweeper’s attention turned to an approaching launch, Frank drew himself stealthily into the dinghy. He stretched out on the bottom of the boat. His hand touched a tarpaulin and he pulled the canvas over him.

  Wood scraped wood as the launch came alongside the speedboat. Frank lifted a corner of the tarpaulin and peered at the strange craft.

  Two men emerged from its cabin and stepped into the speedboat. One was a stranger. The other Kleng!

  They sat with Sweeper in the cockpit of the speedboat and the three began to talk earnestly. Frank strained to hear what they were saying, but the sound of the waves washing against the boats and the tinkle of the bell on the buoy drowned out their words.

  Frank inched toward the bow of the dinghy and felt cautiously for the painter that held it to the speedboat. Pulling on it, he brought the small craft near the one which held the three conspirators.

  The boy could hear their voices distinctly now. He slid under the tarpaulin once more.

  The stranger was speaking. “Alibis! That’s all I hear. The syndicate wants action!”

  “We need more time,” said Kleng.

  “Time for what?” the first man snapped. “For those engineers to fill the valley with water and ruin our plans? For Carpenter’s detectives to make trouble?”

  Frank grinned as Sweeper retorted, “They’re just kids! I’ll take care of them!”

  “See that you do!” the first man told him gruffly. “Kleng, I’ll give you four more days! If Foster hasn’t completed his tests by that time—”

  He broke off as a rattle of tin came from the dinghy. “What’s that?” he demanded.

  Frank suppressed an exclamation of annoyance. His foot had knocked over an oil can, and it rattled from one side of the boat to the other with every roll of the waves!

  “Sounds like a tin can,” Kleng remarked.

  “I’ll get rid of it,” Sweeper said. “That racket makes me nervous.”

  Frantically, Frank felt with his foot, found the can, and pressed it against the side of the dinghy. The rattle stopped.

  “Never mind, Sweeper,” the stranger said.

  Frank breathed in relief until he heard the thin man say softly, “I’m not sure it was just a can. I didn’t pull this dinghy right up to the boat, and it didn’t drift up! And I didn’t spread canvas all over the bottom of it!”

  He walked toward the dinghy, bent o
ver its bow, and yanked off the tarpaulin. “Okay, kid!” he snarled. “Get up! The hide-and-seek game’s over!”

  As Frank stood up, he cast a quick glance toward Merriam Island. His heart sank. The boats had drifted out from the buoy too far for him to swim to safety.

  Sweeper turned to the stranger and declared, “This is one of the snoopers who’s helping Carpenter and Ames!”

  Frank plunged headlong into the sea

  The stranger stared at the youth. Kleng spoke up harshly, “I know this kid. Too smart for his own good. I’ll take care of him this time.”

  The stranger’s hand shot out and pulled Kleng back. “No rough stuff,” he ordered.

  “Let’s cut the kid adrift,” Sweeper suggested. “The tide’s going out. By the time anybody picks him up, we’ll be through with our job.”

  The stranger nodded. “Good idea. Cut the line, Sweeper!”

  The thin man removed a pair of oars from the dinghy, then stepped back into the speedboat and unhooked the painter. The dinghy drifted away rapidly.

  “So long, kid!” Sweeper called mockingly. “Don’t get your feet wet!”

  Frank sat down in the boat and watched helplessly as the tide carried it out to sea. He scanned the water. No ship was in sight.

  “You’ve done it now!” he told himself bitterly. “No oars, no food, no water to drink—and if I know anything about clouds, a storm’s blowing up!”

  Frank studied the water and the black sky. Then, as his eyes fell on the empty oarlocks, a plan formed in his mind.

  He straightened the tarpaulin. Then he twisted and squeezed a corner of the canvas to make a short length of rope, which he thrust through one of the locks. He tied the end into a tight knot, tugging it hard against the oarlock to make sure it could not slip through. He did the same with the adjacent corner of the canvas, knotting it outside the second oarlock.

  Frank sat and waited as the boat bobbed in the darkness. It was not long before the sea began to churn harder. The wind was rising.

  Now Frank stood in front of a seat, holding aloft the untied corners of the tarpaulin. He stretched his arms wide. The impact of the wind rushing into the canvas almost knocked him overboard, but he braced the calves of his legs on the edge of the seat and stiffened himself against the wind and cold water.

  The improvised sail sent the boat plunging through the waves toward the island. Lightning snaked across the sky. Thunder boomed and rain fell in torrents. The waves leaped higher and Frank nearly lost his balance several times.

  Suddenly a gust of wind caught him full force, tearing a corner of the canvas from his hands. He reached for the flapping tarpaulin, but lost his footing just as a huge wave sent the dinghy reeling. Frank pitched forward and plunged headlong into the sea.

  The boy struggled to the surface and shook the water from his eyes. The dinghy was drifting away rapidly, whipped by the wind!

  CHAPTER XII

  Decoy Hunt

  DESPERATELY, Frank’s eyes searched the darkness for the island. A wave lifted him, and he was suddenly conscious of the tinkling of a bell.

  The buoy!

  He turned his head and saw the light a few feet from him, bobbing and blinking. Thankfully, Frank swam toward it and clung to the chain. The island was only a hundred yards away, but his strength was gone. He closed his eyes and waited for the storm to abate.

  It was daylight when the weather cleared. Frank attempted to strike out for the sandy shore. But his arms felt too heavy to move.

  Suddenly he spotted a helicopter approaching the island.

  Frank shouted and waved weakly. He saw a man signal through the craft’s window, and a minute later the helicopter hovered directly over him and started to descend.

  It halted thirty feet above the water and hung in the air. The cabin door was thrust open and a blond-haired youth looked down.

  “Frank!” he yelled. “Hang on! We’ll drop a line!”

  It was Joe! Frank grinned. “I’m all right!” he yelled as loudly as he could. “Just get me out of this soup!”

  Joe laughed with relief. “Okay!” he called. “Catch!” A nylon rescue line with a breeches buoy was dropped, and Frank was drawn up safely into the helicopter.

  “Boy! I was afraid for a minute I was seeing things!” Frank said weakly as his brother and father wrapped him in blankets.

  Frank did not feel strong enough to discuss his experience until he was home and had taken a hot shower. Then, fortified with a bowl of hearty soup, he described in detail what had happened.

  Mrs. Hardy and Aunt Gertrude looked worried. “It’s a wonder you didn’t drown!” his aunt declared. “I think a doctor should have a look at you.” Frank insisted he felt much better.

  “But you must be exhausted,” his mother said. “I think you should get right into bed.” Mr. Hardy agreed.

  “I am pretty tired,” Frank confessed with a smile. As Joe accompanied his brother upstairs, he told him of his discovery that Sweeper was Timothy Kimball Jr.

  “I thought Sweeper was a phony-sounding name,” Frank said, smothering a yawn.

  “Or a nickname,” Joe said.

  But Frank had already stretched out on his bed and was beginning to doze. Joe tiptoed from the room and found his father waiting for him in the study.

  “What Frank overheard last night means we’ll have to act fast,” Mr. Hardy said quietly. “I’m afraid of what the gang will do to Dr. Foster. If only we knew where they’re holding him!”

  “My guess is that they have a hideout on Skull Mountain,” Joe said. “He may be there. If we could find Kleng or Sweeper, we might be able to follow them to the place.”

  “Right,” said Fenton Hardy. “Joe, you go to Kleng’s house. Try to find out if he’s there—if not, when he’ll be back. And, son—be careful.”

  “I understand,” Joe told him.

  “The plumbing shop is closed,” Mr. Hardy went on, “but Kleng and the others may be using it as a meeting place. Do you suppose Chet could stand watch on it? The crooks would be less apt to notice a boy than a man, I think.”

  “Sure, Chet could do it,” Joe said.

  “Good!” The tall detective put on his hat. “I’m going to Brookside and see if I can get Mr. Kimball to talk. He might know something that would help us.”

  Joe phoned Chet and told him of Frank’s rescue. The stout boy was relieved. He quickly agreed to stake out the shop. Then he paused. “Oh!”

  “What’s the matter?” Joe said.

  “I asked Biff Hooper to meet me at the boat landing this morning. I decided it would be easier for two people to look for those wooden things-one could man the boat if the water got rough.”

  Joe debated for a moment. “You’d better go ahead with that plan,” he decided. “The markers may come through the tunnel any time. I’ll watch Kleng’s house and later take over in the bay, while you keep an eye on the plumbing shop.”

  “Check,” his friend agreed.

  The window shades were still drawn in Kleng’s house when Joe drove up. He stepped onto the porch and rang the doorbell. To his surprise, the door opened at once and a middle-aged woman wearing a faded dressing gown faced him. “What d’ya want?”

  “Mrs. Kleng?” Joe asked politely.

  “Yeah.”

  “Is your husband at home?” Joe asked.

  “No.” The woman regarded Joe suspiciously. “What d’ya want him for?”

  “Our kitchen faucet is leaking,” Joe told her. “We need someone to fix it.”

  The woman smirked. “It’ll make a pool if you wait for Kleng to take care of it. He’s away on a trip.”

  “Oh, that’s right,” said Joe, as if he suddenly remembered where the man had gone. “Did he take a boat?”

  “Boat?” the woman asked. “You don’t go to the hills by—” She broke off abruptly and slammed the door in the boy’s face.

  Joe grinned as he ran down the steps. The woman had been caught off guard. So Kleng was in the hills. That must me
an Skull Mountain!

  Joe drove to the boathouse. He guided the Sleuth out of her slip and headed into the bay. A short distance from shore he saw Chet sitting in the skiff with Biff Hooper, a high school companion.

  “Hi!” Joe called. The two waved to him, and Joe brought the Sleuth alongside the skiff.

  “See anything yet?” Joe asked eagerly.

  Chet shook his head. “Maybe the stuff got stuck somewhere in the tunnel,” he said. “How’d you do at Kleng’s house?”

  Joe told him. Chet grinned and said, “Boy, you did good! I hope I find out something at the plumbing shop.”

  “Want me to go out in the Sleuth with you now?” Biff asked Joe.

  “I wish you would, two pairs of eyes are better than one. And Chet had better head for his stake-out.”

  “Fine,” said Biff. “I’ve fished for everything else in these waters. I may as well try my luck at catching a decoy duck!”

  Joe towed the skiff back to the boathouse and moored it there. Chet stepped ashore and saluted importantly. “Detective Morton on duty!” he announced, and hurried away.

  Chet found the plumbing shop closed, as Mr. Hardy had said. The stout boy peered through the plate-glass window, but saw no one inside.

  Directly across the street was a hot-dog stand. Chet brightened.

  “Chow time!” he exulted. “Twelve o’clock!” Besides, he could station himself by the stand. Nobody would suspect he was watching.

  Chet strode over and ordered a hot dog and a tall glass of orange juice.

  Two frankfurters and three glasses of juice later, Chet was still waiting for some sign of action at Kleng’s shop.

  For an hour he strolled up and down the street keeping an eye on the store. Finally he stopped at the stand again and ordered a doughnut. As he took it from the man, he turned to face the store again. Suddenly his eyes widened.

  A man was unlocking the door of the plumbing shop!

  Chet gulped nervously as the man limped into the store. Thrusting the doughnut into his pocket, the stout boy crossed the street. He looked through the window, but could not see anyone.