The Secret of Skull Mountain

by Franklin W. Dixon

  The young detective wet his lips, and his Adam’s apple bobbed as he swallowed. He tried the door and found it locked. Wiping his forehead, Chet paced back and forth for several minutes, staying a short distance from the shop.

  Suddenly he started. Two men were leaving Kleng’s place! Backing into a doorway, Chet watched them cross the street. One was the man with the limp. The other was tall and thin.

  As the pair neared the opposite curb, the taller man glanced around as if he suspected they were being followed. Chet swallowed and tried to look as if he were examining his wrist watch. The two men mounted a motorcycle and roared away.

  Chet’s eyes popped at the peculiar, uneven rhythm of the motor. It was the machine Frank and Joe had described!

  “Well, I guess I cased them!” Chet said to himself. “Now to report to headquarters!”

  At the Hardys’ house, Chet found Mr. Hardy and Frank seated in the detective’s study. After greeting them, Chet earnestly told of his vigil. He wiped his brow as he concluded, “It was touch and go for a few minutes!”

  Mr. Hardy smiled, but declared heartily, “That’s good work, Chet!”

  “Are you going to tell the police?” the stout boy asked eagerly. “They could find the motorcycle and follow it to see where those fellows go!”

  “That’s too risky,” replied Mr. Hardy. “If the gang got wind of the police, they might silence Dr. Foster and clear out fast. There’s a little time yet,” he added. “We must find them quietly on our own, then bring in help.” The detective went on to tell of his visit to Brookside. “I persuaded Mr. Kimball to level with me. Actually he doesn’t know as much as we do.”

  “What about the man with the limp?” Chet asked.

  Mr. Hardy shrugged. “A confederate. I feel sure now it would pay us to post a regular watch on the plumbing shop.”

  Chet asked, “You mean me?”

  “Why not?” the detective queried. “You did a good job today!”

  The boy beamed. “Leave it to me, Mr. Hardy!”

  Frank stood up. “Dad says Joe is watching Kleng’s house.”

  “No, he was there,” said Chet, and told what Joe had found out about the plumber.

  “He’s gone to Skull Mountain, all right,” said Frank, “and that’s where we should go to search for that hideout.”

  “You can start tomorrow,” his father agreed. “Where’s Joe now, Chet?”

  “Out in the Sleuth with Biff Hooper. They’re looking for the stuff we planted in the reservoir.”

  “I’ll go down and help them,” said Frank. “Coming, Chet?”

  “You bet.”

  It was late afternoon when the boys arrived at the boathouse. The Sleuth had not returned.

  “We’ll use our rowboat to look for Joe and Biff,” Frank said.

  They found the Sleuth anchored in the bay. Joe and Biff were sitting in the cockpit. Frank rowed alongside. “Any luck?” he asked.

  “No,” his brother replied. “I’m afraid the stuff came through during the storm and was washed out to sea.”

  “If so,” Frank said, frowning, “we’ll have to forget it for now. First thing in the morning we’ve got to go to Skull Mountain and search for Dr. Foster.”

  The Hardys swapped places, Frank taking the wheel of the Sleuth, Joe joining Chet in the rowboat. They hooked it by a towline to the speedboat and started off. Frank guided the two crafts as close to the rocky shore as he dared.

  The boys examined the numerous coves which bit into the shoreline of the bay. Hours later, when it was dark, they still had seen no sign of the markers.

  “Let’s quit,” Chet pleaded. “I’m starved!”

  “We’ll try one more cove,” Frank said. “If we don’t spot the things, we’ll go home.”

  He steered the Sleuth toward a rocky slit in the shore, then cut the motor. The two boats drifted into the cove.

  Frank trained the speedboat’s searchlight on the steep shore. As he swept the light slowly along the water line, the other youths searched with their flashlights.

  The lights made a complete sweep around the cove, but the boys saw nothing in the water.

  Discouraged, Frank swung his craft slowly back toward the mouth of the inlet.

  Suddenly Joe thought he saw a small white object bump against the Sleuth and veer away. “Hold it!” he yelled.

  Frank quickly cut the motor and Joe leaned over the bow of the rowboat. He aimed the beam of his flashlight at the water.

  With a whoop of joy he reached down and held up a dripping object. “Here it is—our duck!”

  CHAPTER XIII

  Dangerous Cargo

  “THAT DOES IT!” Frank exclaimed as Joe showed the wet decoy to his excited companions. “Now we’re sure there’s an underground channel from the reservoir to the bay!”

  “It must be a rough ride through the tunnel,” Biff remarked. “Look at the scratches on that duck!”

  “Let’s see,” Frank said, and Joe passed him the decoy. He examined it carefully. “No clues on this, but it gives me an idea. Let’s look for the barrel stave and pine slab. Maybe there will be something on them to show where they entered the channel.”

  Using the Sleuth’s searchlight, the boys scanned the surface of the water, but found nothing more,

  “I bet the rest of the things are stuck somewhere in the tunnel,” Chet said.

  Biff peered over the side of the speedboat. “Must be a current down below,” he observed. “Look how roily the water is here.”

  Frank nodded. “It’s probably the fresh water flowing in from the reservoir—and stirring up the sand and mud particles on the bottom of the cove.”

  The Hardys decided to return at daylight to see if the stave or slab had come through. Frank pressed the Sleuth’s starter button, and the motor throbbed. Before he eased the two boats carefully out of the cove, Joe took a piece of white chalk from his pocket and inscribed a large X on a rock, well above the high-tide mark.

  At dawn the Hardys returned and easily found the chalk-marked cove again.

  As Frank guided the Sleuth into the inlet, Joe grinned and pointed to a red-and-white object whirling in the water. “How’s that for luck!” he exclaimed.

  Frank eased the craft over and Joe seized the barrel stave.

  Quickly they examined it. Stuck in the cracked wood was a twig of bramble bush!

  “That’s our clue!” Frank exclaimed. “There can’t be bramble in the underground channel, so this twig must have caught on the stave as it was swept into the opening.”

  Joe chuckled. “Now all we have to do is locate the right bramble bush and we’ll know where the entrance to the tunnel is.”

  Elated at their discovery, the boys headed the Sleuth back to the boathouse. The fresh breeze cutting across the bay aroused their appetites.

  “I could eat a stack of flapjacks,” Joe said as they stepped ashore.

  “So could I. With sausages.”

  As the boys were crossing the boat landing on their way to a nearby diner, Frank suddenly clutched Joe by the arm. “Do you see what I see?” he whispered, pulling his brother down with him behind an empty barrel.

  Walking along the dock was Sailor Hawkins! The old sea dog’s back was toward the boys, but his short, squat figure and rolling gait were immediately familiar.

  ‘What do you suppose he’s doing in Bayport?” asked Joe.

  Frank shook his head. “One of us had better follow him,” he said. “He may be on some business for Sweeper.”

  “I’ll do it,” Joe told him. “You drive home and pick up the stuff we’ll need for the camp. I’ll phone you later and tell you where to meet me.”

  Joe followed Hawkins down the dock to a loading platform. He kept his eyes on the sailor, while side-stepping the shouting, sweating longshoremen who were trundling barrels and crates onto the wharf.

  The arm of a boom swung out from a freighter over the loading platform and hooked a rope net laden with heavy boxes. The cable drew taut and the n
et was hauled swiftly into the air.

  “Look out!” a dockhand yelled frantically.

  Joe’s head snapped up at the warning. One of the rope strands had broken, and the hook had torn loose from the net. The heavy cargo was hurtling down on him.

  He flung himself to one side and the boxes crashed to the dock—not six feet away! There was a surge of excited voices as men looked down at him from the rail of the freighter while others ran toward him along the wharf.

  A longshoreman helped the youth to his feet. “Are you hurt?” he asked.

  Joe shook his head and brushed the dirt from his clothes. He looked at the spot where he had last seen Hawkins, but the sailor had disappeared.

  With quick thanks, Joe shook off the dockhand and made his way toward the row of supply houses, cheap restaurants, and second-hand stores which lined the street opposite the wharf.

  He looked through the windows of the stores, but did not see Sailor Hawkins.

  Finally, at the end of the row, Joe came to a large warehouse. Cautiously he stepped inside. The dim interior was stacked with crates, but there were no longshoremen in sight. Joe stopped short. Not far away on a box sat Hawkins! His head was bent as he lit an old corncob pipe.

  Joe slipped behind a large crate and waited. Soon he heard uneven footsteps approaching along the wooden floor. From his hiding place, he could make out a small, furtive-looking man who walked with a limp!

  Joe tingled with sudden excitement. During the search for the outlet in the bay, Chet had told of seeing a man with Sweeper whose description tallied with this stranger’s.

  The limping man went straight to the sailor and they exchanged a few whispered words. Then the small man took some bills from his wallet, counted them carefully, and gave the money to Hawkins.

  “For the food,” he said aloud.

  At that moment a dockworker came pushing a hand truck through the warehouse door. He stared curiously at the two men, then moved the truck toward the crate which concealed Joe.

  “Oh no!” Joe thought. “Not this one!”

  The laborer tilted the crate and slid the shoe of the truck under it. Joe glanced helplessly at the nearest place of concealment. It was the stack of crates beside which Hawkins and the limping stranger were standing.

  An instant later the longshoreman saw the boy. “Hey!” he demanded. “What are you doing here?”

  Hawkins and the stranger turned swiftly. “So it’s you!” the old sailor roared, taking a threatening step toward Joe. “You blasted little spy!’

  The limping man grabbed the sailor’s arm. “No, Hawkins!”

  He whispered something rapidly in the seaman’s ear. Then the two men separated. Hawkins ran out the front door of the warehouse, while the man with the limp made for the rear exit.

  Joe swerved past the dockworker and raced after Hawkins. The old sea dog’s short legs carried him with surprising speed, but Joe was more than a match for him.

  He saw the sailor dodge into a doorway. Joe quickly stepped behind a truck. After a moment he saw Hawkins peer out from his refuge. Satisfied that he had shaken off his pursuer, the seaman walked calmly along the row of stores and entered a self-service grocery.

  Joe went to the window of the store and stealthily looked in. Hawkins was going slowly up one of the aisles, selecting groceries.

  “He’ll be there for a while,” Joe thought, noticing that a long line was waiting at the single check-out counter. The boy hurried into a drugstore and telephoned Frank.

  “Meet me as soon as you can,” Joe instructed his brother and recounted his adventure. “Hawkins is buying a big load of supplies. They must be for the gang up on the mountain!”

  When Joe hung up, Frank relayed the information to their father. “Maybe we can follow Hawkins to the hideout!” the boy said as he slipped into his jacket.

  “I’d go with you,” said Mr. Hardy, “but I’ve had a call from the Chicago police asking me to stand by. I’ll have to go there as soon as they’re certain they’ve located the syndicate headquarters.” He reminded Frank to be cautious and added, “Good luck, son!”

  Frank dashed to the convertible, which was already packed with their gear, and drove to the grocery.

  “Hawkins loaded the supplies into an old jalopy and left five minutes ago,” Joe said as he hopped into the seat beside Frank.

  A few miles out of Bayport on the highway leading toward Skull Mountain the boys saw a dilapidated sedan ahead of them.

  “That’s the car!” Joe exclaimed.

  Frank let the convertible slow down and adjusted its speed to the sedan’s rattling pace.

  Soon the old car turned off onto the same dirt road the boys had used to detour the landslide. Frank and Joe followed at a distance. At the foot of the narrow trail which mounted the slope to the ridge, the sedan stopped. Quickly Frank parked the convertible behind a clump of trees.

  A man the boys had never seen came out of the brush and helped Hawkins lift the heavy crate from the sedan. Together they started to carry it up the path.

  The Hardys waited until Hawkins and his companion had a good head start, then followed. The men stopped frequently to rest, but finally reached the top of the mountain and disappeared behind a clump of boulders.

  Frank and Joe quickly climbed the last steep section of the trail and cautiously rounded the same rocks. They stopped short, staring in surprise at a large empty clearing.

  The stocky sailor and his helper had vanished!

  CHAPTER XIV

  A Mountain Puzzle

  “WHAT happened to them?” Joe asked.

  Frank shook his head. “It beats me,” he replied. “I don’t see where two men could have gone so quickly—especially carrying that heavy box.”

  In the clearing where Frank and Joe stood there were only a few patches of blueberry bushes as high as the boys’ knees. The rest of the mountaintop was covered with trees. The brothers searched the woods, but found no trace of Hawkins or his companion.

  “Come on!” Joe said impatiently. “This is getting us nowhere.”

  They started down the mountain toward the reservoir, and half an hour later arrived at the camp. Bob and Dick greeted them with enthusiasm. It took the boys a full hour to recount their adventures and discoveries since they had last seen the engineers.

  “By the way,” Joe said, “you were absolutely right about the subterranean channel.”

  Bob and Dick exchanged looks of astonishment. “How do you know?” Bob asked. “We’re supposed to be the experts here, and you’re not giving us a chance!” He grinned.

  Frank explained the boys’ experiment. “The gang must have devised a way to drain the water off at will,” he added. “That’s why it happens only at night.”

  “And naturally when it’s dark,” Joe put in, “it would make it tougher to trace the current.”

  “But we have a clue that may help you,” Frank said, and told of the bramble twig.

  “Fellows, you’re great!” Bob exclaimed. “I’ll put the sounding crew to work looking for the bramble patch.” He went on to say that the new electronic equipment would not arrive until the next day, because it was coming from New York. “The water shortage is getting worse,” he added soberly. “We’ve just got to find that outlet!”

  “And Joe and I have to locate the hideout and Dr. Foster,” Frank said. “You know,” he went on thoughtfully, “the gang must have some kind of equipment in the tunnel to shut the water off. If we find the channel, we might catch one of the gang members in there and make him talk.”

  “That’s an idea!” said Joe. “Let’s concentrate today on finding the channel opening. Too bad Chet’s staked out at Kleng’s shop,” he added. “We could use him!”

  After lunch the four set out. Bob and Dick circled the reservoir in the rowboat while the Hardys and the six-man crew walked along the shore to investigate the slopes above the present water line.

  Hour after hour passed as the group inspected the banks, prodding and tear
ing with long poles, sticks and hatchets in an attempt to expose the earth wherever they found patches of brambles.

  The prickly foliage clung to the rocky slope, scratching the boys’ hands and ankles when they dug into the underbrush.

  “I have a feeling we’ve been through this before!” Joe said gloomily.

  Late in the afternoon the four returned to the camp for a quick supper, but resumed their work at the reservoir immediately afterward. As dusk settled over the valley, the water level began to drop noticeably.

  Suddenly Frank gripped Joe’s arm and pointed toward the crest of Skull Mountain, still bathed in a clear, yellow light. “Look!” he exclaimed. “The smoke again!”

  Joe gazed at it intently for a few moments. “It looks to me as though it’s coming from the clearing where Hawkins and his pal disappeared so suddenly.”

  “You’re right!” Frank said.

  Bob and Dick were still in the rowboat. The Hardys shouted that they would join the engineers later, and started up the hillside. Darkness closed in around them as they climbed toward the steady stream of smoke.

  “I’ve got a pocket flashlight,” said Frank, “but we’d better not use it. No telling who may be around here.”

  “I hope that fire’s still burning when we get there.” Joe grunted. “I’ve run up and down this hill so often I feel like a mountain goat!”

  No sooner had he spoken than the column of smoke vanished.

  “That does it!” Joe declared in disgust.

  “Come on!” Frank urged. “We’ve almost reached the top. It would be foolish to turn back now.”

  Clambering over rocks in the darkness, the brothers finally arrived at the treeless patch on the summit.

  “Not a trace of smoke,” said Joe.

  “We’ll wait,” Frank decided. “If it starts up again, we’ll be here to spot it.”

  The boys made themselves comfortable on the ground. Overhead the stars sparkled, and a full moon rose slowly above the hill on the other side of the reservoir. The night air was cool and fresh. As they sat quietly, a figure emerged from the trees beyond the clearing.