The Secret of Skull Mountain

by Franklin W. Dixon

  Joe bounded up the slope after the invisible figure, but in a few minutes the crackling of brush ceased. He searched among the trees and beat the bushes, but could find no one. Disappointed, he started down the hill.

  “Over here, Joe,” called Frank.

  The younger boy hastened to his brother and Chet who stood under a large tree near the edge of the woods. Without a word, Frank pointed to the ground.

  Six sets of electronic sounding equipment lay smashed beyond repair.

  As Joe groaned and shook his head, the men of the sounding crew came running down the hill.

  “I knew it!” exclaimed a tall man. “As soon as I heard the noise!”

  “Another hatchet job!” said one of his companions. “We should never have left the gear here, but we decided to take a hike and the stuff was too heavy to carry.”

  Bitterly the crew gathered up the broken pieces and started back to the shack to report to Bob Carpenter.

  “Those men were being watched,” Frank said quietly. “Probably we are too.”

  “Oh, that’s great!” croaked Chet. “Why did I ever leave home?”

  The three started walking toward Bob’s shack. Suddenly Frank exclaimed, “Look!” He pointed to the crest of the mountain. A thin column of smoke was rising from it!

  “Come on!” he exclaimed. “We’re going to find that fire!”

  “Wait!” wailed Chet. “What about lunch?” But the Hardys were already climbing up the slope. Chet groaned and followed.

  Soon they found themselves skirting Potato Annie’s garden. The old woman had been pulling turnips, carrots, and beets. As the boys hastened past, she picked up a basket laden with the vegetables, then hobbled up into the woods.

  “Wonder where she’s taking all that food,” Joe said.

  “Don’t know,” replied Frank, “and we can’t stop now to find out. Maybe she sells ’em.”

  “We’d better check on her later,” said Joe. He glanced back. Chet was puffing to catch up, but the woman was hurrying away fast.

  Climbing steadily, the three youths hoped to reach the smoke before it vanished. As they crossed a small clearing, a shot rang out.

  “What was that?” Chet yelped, ducking.

  They looked behind them to see Sailor Hawkins standing among the trees, his rifle still smoking. He shook his fist at them. “Get off the mountain!” he roared. “Ye no-good swabs!” The boys hurried into the woods.

  “Who’s he?” Chet demanded, glancing behind him in time to see Hawkins disappear down the slope.

  “Just a friend,” Joe replied airily.

  “Some friends you’ve got!” Chet retorted. “When they’re not throwing rocks at you, they’re throwing bullets!”

  Frank and Joe laughed. Then they looked up toward the smoke. It was gone!

  “Oh, no, not again!” exclaimed Joe.

  Frank considered. “We’ve come this far, so we may as well keep going,” he decided.

  They had just resumed their climb when they heard the sound of an ax striking wood. It seemed to be only a few hundred yards away!

  The boys looked at one another excitedly. “Maybe that’s our hatchet man!” Frank said softly. “Let’s go!”

  Half running, the three made their way through the woods toward the sound. Except for the echoing blows of the ax, the forest was strangely still.

  They clambered over scattered rocks and skirted a cliff. As the ax rang more loudly, they crept forward.

  Suddenly the noise stopped. The boys halted and stared ahead anxiously. Had someone spotted them?

  They waited a moment for the chopping to resume. When it did not, Frank broke into a run, motioning the others to follow. Soon they came to a small clearing.

  Frank pointed to the stumps of several fresh-cut trees. He went over to them and examined the surrounding earth. “Look here,” he said.

  Joe’s eyes followed his finger. Pressed into the soft earth were the footprints of the man with the missing toe!

  Frank traced the prints for a short distance and saw that they followed a narrow dirt path. He beckoned to the other two.

  Walking stealthily, wondering how close they might be to their quarry, the boys trailed the mysterious prints. Once they lost them, but Joe found a fresh-cut tree limb the man apparently had dropped, and they soon picked up the trail.

  As they hurried forward, Chet’s eyes fell on a pocketknife lying beside a tree. He stared at it disbelievingly. Engraved on it were the initials C.M. “Hey!” he called softly. “Look what I found!”

  Frank and Joe joined their friend. “It’s my knife! I had it in the pocket of the pants that were stolen!”

  “Swell, Chet!” Joe congratulated him. “If we catch up with this guy, maybe you’ll get back your clothes!”

  Buoyed up by their find, the searchers hurried forward. Suddenly the trail vanished in an open patch of grass.

  As the boys paused, they heard a faint sound in the woods to their right. Frank signaled the others to follow him. They crept forward, taking care not to step on twigs.

  A moment later they stopped abruptly at the edge of a small clearing. On a fallen bough sat a gaunt-faced man so thin that his bones seemed to protrude from his flesh.

  Frank nudged his brother and pointed to the fellow’s right foot. It had only four toes!

  Gray, shaggy hair hung down to the man’s neck, and a matted beard covered his chest. He was eating a turnip, gulping it down without chewing, and on the ground beside him lay a dozen pieces of split wood and an ax.

  His shirt was tattered and sleeveless. But he wore a new pair of khaki shorts. They hung on him in loose folds.

  “My shorts!” exclaimed Chet.

  The man stood up swiftly, dropping the half-eaten turnip. He fixed the boys with a fierce stare. Then he grabbed the ax and swung it around his head.

  “Watch out!” Joe yelled. “He’s going to throw it!”

  CHAPTER VIII

  A Disappearance

  INSTANTLY the man lowered the ax. With a wild laugh, he fled into the woods.

  “After him!” shouted Joe.

  The boys chased the tall, bony creature through the woods at breakneck speed.

  Suddenly he scooted into a deep gully. The boys crashed down the brush-covered slope behind him, but could see him nowhere. They searched amid the thick bushes and boulders.

  “No use,” said Joe, disgusted. “He’s done it again.”

  “He must know this mountain like the back of his hand,” Frank said with a sigh.

  “Well, at least we know he’s the man with the missing toe,” Joe remarked as the boys climbed out of the ravine.

  “And we know he stole my clothes!” Chet added heatedly.

  “It’s too bad he couldn’t steal a tailor with them,” Frank put in, grinning. “One pair of your shorts is big enough to make two or three outfits for him!”

  Chet looked disgusted. “My best pair of shorts!”

  Their conversation turned once more to the wild man. He had indeed set off the explosion near the boys’ tents. The firewood he cut was probably the source of the smoke they had seen. But where had he come from? Why was he sabotaging the reservoir project?

  “He must live on the mountain,” Frank said. “I’ll bet he’s a hermit.”

  “I’d hate to meet that skull-toting guy in these woods on a dark night!” Chet declared. “Now let’s get back to camp, fellows, please. I’m hungry!”

  The boys descended to the shack and ate a late lunch. They found a note from Bob explaining that he and Dick had gone to Bayport to order more sounding equipment and would not be back until the next day.

  “Tonight we’ll drop some articles in the reservoir,” said Frank, “and see if we can find them in the bay.”

  “How about shingles?” asked Joe, nodding to the pile in the corner.

  “Nope. We need something easier to see. Too bad we haven’t some dye. That’s often used for tracing currents.”

  The boys searched the s
hack and found an old decoy duck in the back of a cupboard. Joe guessed that the dam-builders had used it for hunting the autumn before. “There are some lakes near here,” he said.

  Chet found a large slab of yellow pine and an old barrel stave behind the shack.

  Using paint from Bob’s supply shelf, the boys made the duck white with red initials: F and J. They colored the pine slab red, and put red and white stripes on the barrel stave, which had a split in it. Then the articles were placed in the afternoon sun to dry.

  At nightfall the boys gathered them up.

  “Look, Chet, you don’t have to come,” said Frank. “There’s no sense in all of us taking the risk.”

  “No sir,” said Chet firmly, “I’m going with you.”

  “Good old Chet, you always come through in the pinch,” said Joe.

  Chet looked pleased, then said, “To tell you the truth, I’m not keen to stay up here alone with that creepy hermit running around.”

  “I don’t blame you,” Joe said with a chuckle as they made their way quietly down the slope to the reservoir.

  The boys’ scalps prickled as they stepped into Bob’s rowboat and pushed off. Were any unseen snipers watching them? Tense and silent, they waited for the crack of a rifle.

  Chet glanced around apprehensively as Frank rowed over the murky water. The squeak of the oars and the trickle of water from the blades were the only sounds.

  “Let her ride,” Joe said as the boat swung close to the opposite shore.

  Frank hauled in the oars, and Joe put the duck in the water. Frank rowed on, keeping the craft a few feet from the shore. Then Joe and Chet quietly placed the pine slab and barrel stave overboard.

  Quickly Frank headed for the dock where he hooked the boat to its mooring line. The boys stepped ashore and hurried up the hill to the shack. Not until they were inside did they speak.

  “Whew! We made it!” Frank grinned in relief as Chet sank into a chair.

  “It must have been the snipers’ night off,” said Joe.

  “If that underground channel exists,” said Frank, “at least one of those things ought to be sucked into it!”

  “How long do you suppose it will take for this stuff to go through the tunnel?” Joe asked.

  Frank thought a moment. “I don’t know. If this channel were a straight flume or chute, the articles might pass through in a couple of hours. But the tunnel might not go the most direct way and there may be obstructions. It could take a couple of days.”

  “Besides,” said Chet, “the water only flows at night.”

  “All the same,” Joe put in, “we had better search for the stuff as soon as we can. It might go through more quickly than we think. Then the tide could carry it out of the bay, and we’d never know.”

  Frank said, “I’d like to drive back to Bayport tonight to check with Dad and Callie. How about you two?”

  “Suits me,” Joe replied.

  “Me too,” Chet said, glancing at his watch. “Do you think Aunt Gertrude will feel like a midnight snack?”

  Joe grinned. “She will if you ask her!”

  They packed a few things and Frank left a note telling Bob and Dick of the day’s events and saying the boys would return in a day or two.

  Aunt Gertrude was in bed reading when the three arrived at the Hardy home. When she heard that Chet had set his heart on having a slice of her pie or cake before going home, she goodnaturedly put on a robe and came downstairs. Soon the boys were enjoying sandwiches, milk, and generous slices of cherry pie.

  “Where’s Dad?” Joe asked.

  “He had a telephone call this evening and went out,” Aunt Gertrude said. “He said he wouldn’t be back until tomorrow. That’s all he told me,” she added with a sniff.

  Chet ate the last crumb of his pie and announced that he must start for home. “I’ll see you tomorrow,” he told the boys. He beamed at Aunt Gertrude. “Thanks for the pie!”

  The next day the boys were at breakfast when the telephone rang. Mrs. Hardy answered the call. “It’s Callie,” she told Frank. “She says she must see you right away!”

  “Where is she?” Frank asked, pushing back his chair.

  “In the drugstore—a few doors from Kleng’s plumbing shop,” his mother said.

  “I’d better get right over!” Frank said excitedly, thrusting his arms into the sleeves of his jacket.

  “I’ll go with you!” Joe put in promptly.

  “Okay, but hurry!” Frank called, rushing out the door. “I’ll get the car.”

  Ten minutes later Frank parked in front of the drugstore. It was a bright, windy day and Callie’s blond hair was blowing as she hurried to meet the boys.

  “What happened?” Frank asked worriedly. “You look frightened!”

  “I am,” Callie said. “At least, I was,” she amended with a little laugh. She looked nervously up and down the street, then beckoned the two boys into the doorway of a vacant store where they could not be seen so easily.

  “None of us girls had any luck yesterday,” she said, “so I went to Mr. Kleng’s shop this morning. And while I was in there buying washers, the wind blew the screen door open and all the papers flew off Mr. Kleng’s desk. Of course I helped him pick them up. And, Frank, one of them was a telegram! Well, when Mr. Kleng saw it in my hand, he was furious. I never saw a man so angry!” She shivered. “He snatched it away from me.”

  “Did you see what it said?” Joe asked.

  “Yes, I couldn’t help it. I think I remember all the words.”

  “Go ahead,” said Frank, taking a notebook and pencil from his pocket.

  “The message said: ‘Syndicate convinced you are stalling. What’s wrong? Can Retsof deliver? When?’ And it was signed ‘Ben.’ ”

  “Retsof,” Frank mused. “Sounds like a foreign name.”

  “Maybe it’s in code,” Joe suggested.

  “Could be,” Frank agreed, studying the name thoughtfully. “Yes!” he cried out. “It’s Foster spelled backward!”

  Joe was elated. “That’s proof Kleng is mixed up in Dr. Foster’s disappearance!”

  The boys grinned at one another, and Frank looked at Callie with admiration. “Do you know where the message came from?” he asked her.

  “Chicago,” Callie answered promptly. “And I have something else to tell you,” she added, her eyes sparkling. “Guess who came to see Mr. Kleng while I was in there?”

  “The tall, thin man!” Frank exclaimed.

  “Yes,” Callie said triumphantly. “Mr. Kleng called him ‘Sweeper.’ ”

  “I thought so,” Frank remarked grimly. “Sweeper is the man we saw on the mountain, talking to Sailor Hawkins and one of the men who held me up.”

  Joe spoke up. “And Kleng might have been the other one. We’d better have a talk with him.”

  “You can’t!” Callie exclaimed. “He locked up his shop right after I left. He said he was leaving town!”

  The boys exchanged glances of dismay. If Kleng left Bayport, they might never solve the two mysteries.

  “Did I do a good job for you?” Callie asked.

  “You were a doll,” Frank said warmly. “Come on. We’ll drive you home.”

  At Callie’s house Frank asked to see a telephone directory. “I’m going to look up Kleng’s home address,” he explained to Joe. “If he told Callie the truth, maybe he’s still home packing.”

  Frank wrote down the street and number, then drove to the plumber’s house.

  It was a drab, two-story frame dwelling, set back from the street by a short lawn. As the boys went up the steps to the porch, they saw that the shades were drawn.

  No one answered the doorbell. Joe tried to peer through a window, but the shade completely shut off his view.

  They returned to the car. As Joe got in, he looked over his shoulder. Was it his imagination —or had he glimpsed a woman’s face staring at them from an upstairs window?

  He told Frank about his suspicion, and his brother deliberated. “If it was
Kleng’s wife, he can’t have gone away for good. We’ll go back some other time and try our luck.”

  Mr. Hardy had returned when the boys arrived home. They showed him Frank’s copy of the telegram Kleng had received, and he studied it with great care.

  “We must do our best to keep track of Kleng,” the detective remarked.

  Frank told him of the possibility that the plumber had left Bayport. Mr. Hardy frowned.

  “He may have gone to Chicago.” He reached for the phone and dialed information in that city. While the call went through, he reread the telegram message. “I’ll try to trace the sender of this message,” he told the boys. “Through him we may pick up Kleng.”

  Frank and Joe left their father to complete his call.

  As Frank closed the door to Mr. Hardy’s study, he said to Joe, “The sooner we take the Sleuth and begin looking for the articles we dropped into the reservoir last evening, the better. The tide will be going out in another hour.”

  The boys drove to the boathouse where they kept their trim white craft. Frank stepped into the cockpit and pushed the starter button.

  The motor failed to catch. As Frank put out his hand to try again, the boys heard the uneven roar of a motorcycle behind the boathouse. Then it stopped.

  Joe saw a tense look come over his brother’s face. “That motorcycle!” Frank whispered. “It sounds like the one Sweeper was riding the night he held me up!”

  CHAPTER IX

  Tiger Trouble

  FRANK leaped from the Sleuth and ran toward the rear of the boathouse. Joe followed, close on his brother’s heels.

  The motorcycle was parked in a nearby shed, but its rider was nowhere to be seen. In a corner of the flimsy building was a door leading to a boat landing.

  “He must have gone that way!” Frank said.

  He flung open the door and they rushed out onto the landing. A few feet away a tall, thin man wearing a tan jacket stood at the wheel of a speedboat.

  “It’s Sweeper!” Frank exclaimed softly.

  The boys heard the sputtering roar of a motor, and the craft curved out into the bay. “Come on!” Frank cried, racing for the Sleuth. “We’ll follow himl”

  “Go ahead,” Joe yelled. “I’ll try to trace the owner of the motorcycle!”