The front door opened and sharp heel taps sounded on the floor. From their hiding place, the boys saw a woman open the office door. The light fell on her face.
Mrs. Kleng! She stared into the back room. “What are you two doing here?” she demanded.
Then the boys saw Sweeper’s arm pull her into the office. The door slammed shut.
Joe glanced at Frank. “What shall we do?”
“Better wait for Chet and the chief. If the three in there try to leave, we’ll stop them.”
Angry voices sounded in the office. In shrill tones Mrs. Kleng denounced Sweeper and his companion for their treachery.
“My husband planned this whole reservoir setup,” she declared, “and now you think you’re going to rob him! He’s the one who got the syndicate to promise the backing and what have you done, but—”
“I’ve done plenty!” Sweeper cut in. “And if it weren’t for my brains, this whole operation would have been sunk!”
The woman snorted contemptuously. “Brains! You’re so stupid you left the front door unlocked while you robbed the safe!”
Green spoke up excitedly, “We couldn’t help it. The lock was jammed!”
“Pipe down!” ordered Sweeper. “Somebody’ll hear you!”
After that the voices fell and the boys could catch only a sharp word now and then. Suddenly the front door opened and the Hardys whirled to see Chief Collig with Chet.
Quietly the two walked to Frank and Joe. “Reinforcements coming,” the chief said softly. “The men still in there?”
Frank nodded. “Mrs. Kleng’s with them, and they didn’t seem too happy to see her.” Briefly, he whispered what he and Joe had overheard.
Chief Collig nodded, then walked past the boys to the office. With one quick movement, he threw open the door. “All right, lady,” he said. “Step aside.”
Mrs. Kleng whirled around with a startled look. “What’s the idea?” she asked.
“You’re all under arrest!” the chief announced gruffly.
Sweeper saw the boys and snarled. Green stood gasping like a hooked fish.
“You can’t arrest me!” Mrs. Kleng’s voice rose shrilly. “My husband owns this shop! I came here for some money he asked me to get for him and found these two crooks”—she pointed a bony finger at Sweeper and Green—“breaking into the safe! They’re the guilty ones!”
Collig was not impressed. “I’m holding you as a material witness.”
Mrs. Kleng flashed him a bitter look. “Do what you want. I won’t talk.”
The chief produced a pair of handcuffs and chained the two men together.
“Sweeper,” said Frank, “where’s Dr. Foster?”
“I don’t know what you’re talking about,” the tall man replied.
“You’d better tell us,” Joe said sharply.
Sweeper raised his brows. “Take it easy, boy. You don’t know who I am. I’ll be out of this jam before daylight.”
“You’re Timothy Kimball Jr.,” said Joe, “and this is one time your father can’t help you.”
The thief stared at Joe. “You think you’re pretty smart, figuring that out.”
“You’d be wise to cooperate, Kimball,” said the chief. “Where’s that hideout?”
Sweeper’s lips tightened. “I’m telling nothing,” he said. And neither is Green, if he knows what’s good for him.”
The small man gulped.“ ’Course not, Sweeper. I won’t talk.”
Sweeper gave the Hardys a twisted smile. “It’s all up to you, boys,” he said. “Good luck!”
Flanked by the boys, the chief marched his three prisoners to the door, where a squad car had pulled up.
“This takes care of some of the crooks,” Joe said, grinning. “Now for the others!”
CHAPTER XVIII
The Secret Tunnel
DAYLIGHT was breaking over Skull Mountain when Frank and Joe climbed to the top of the narrow trail. Bob and Dick greeted them on the ridge.
The boys unslung the gas masks from their shoulders and handed one to each of the engineers, keeping a mask apiece for themselves. All had canteens and flashlights.
“Where’s Chet?” asked Dick.
“Still in the sack,” Joe replied with a grin. “He’s coming later in his jalopy.”
“See your dad?” Bob questioned them, looping the strap of his mask around his neck.
“No,” said Frank. He quickly told all that had happened the night before.
“Did you tell the police about the tunnel that you think goes to the gang’s hideout?” Bob asked.
“Yes,” replied Frank, “and while we were at Chief Collig’s office last night, he called Dad in Chicago. We reported all we’d discovered so far, and it was decided to round up the gang here tomorrow.”
Joe explained that Mr. Hardy was ready to arrest the members of the syndicate in Chicago, but figured he might need one more day.
“In the meantime,” Frank put in, “he wants us to locate the cavern and any tunnels that go to it. We’re to sketch the layout for the police, so they can cut off all avenues of escape.”
Bob gave a low whistle. “If one of the gang catches sight of you, it could wreck the whole operation.”
“To say nothing of what they’d do to you if they nab you,” Dick added.
“It’ll be touchy,” Frank agreed with a grin.
“We’ll be glad to help you,” said Bob.
Dick nodded. “Just say what you want us to do.”
“Thanks,” said Frank. “First let’s see if there’s water in the channel. After that, we’ll tackle the right-hand branch of the tunnel.”
A moment later the rectangular slab of rock had been removed and the crevice exposed.
Joe slid into the fissure, then Bob and Dick followed. Frank came last, and using the handhold, pulled the rock over the opening. The Hardys turned on their lights and crawled single file into the low-roofed tunnel ahead.
The four worked their way downward on their hands and knees. After a while they were able to walk erect. When they reached the fork, Joe paused. For a few minutes the boys listened for a sound from the right-hand shaft.
“You think the gang is down there now?” Bob asked quietly.
“Could be,” Frank replied. “We’d better be quiet. No telling how sound carries in these passages.”
Walking softly, the boys descended the tunnel which led to the underground stream. As they drew closer, the Hardys realized there was no sound of rushing water. Soon the floor leveled off, and the four saw the small landing ahead. They hastened to the edge and Frank shone his light downward. The floor below was damp, and tiny pools of water sparkled in the light. But the stream they had seen the night before was gone!
“That proves it!” Frank declared, his eyes shining. “This is the tunnel which runs from the reservoir!”
Bob nodded. “There’s no doubt of that now,” he said slowly. He stared down at the empty channel. “There can be only one explanation why the water flows through at night and not during the day,” he added. “And that’s a lock! It’s probably close to the mouth of the tunnel.”
Dick grinned. “All we have to do now,” he pointed out, “is what we’ve been trying to do all along—locate the entrance to the channel and close it!”
“Maybe we could just block it off here,” Joe suggested.
Bob shook his head. “We couldn’t be sure the block would hold in this place.”
Joe played his flashlight beam down on a jagged gap in the rock wall across the shaft.
“As long as the water’s dammed up during the day,” he said hopefully, “one of us might be able to crawl through that opening and along the tunnel to the mouth!”
“Nothing doing!” Frank told his brother. “That hole is too small as it is, and the passage may get a lot smaller as it goes along!”
“Frank’s right, Joe,” Bob said. “It could be suicide! We’ll just have to keep hunting for the mouth of the tunnel until we find it.”
&
nbsp; Joe chuckled. “If the roundup comes off tomorrow, you won’t have to look any more. We’ll get the information from the gang.”
But as the boys climbed up the tunnel again, the Hardys thought seriously of the next day. As seasoned detectives, they knew better than to be overconfident.
When the four reached the fork, they stopped.
Dick nodded toward the other branch of the tunnel. “Ready for a look-see?” he asked softly.
“Wait,” said Frank. “I think it would be wise to cover ourselves. Chet should be at the camp by now. We’ll go down and tell him what we’re doing. If we don’t come back in a reasonable time, he can go for help.”
The others agreed and they continued to the top of the mountain. After crawling out of the crevice, they placed the stone over it and hurried down the mountain.
When they reached the shack, they found Chet pouring himself a glass of milk.
“Make it five glasses,” Dick said, “and we’ll tell you our news.”
Joe spoke up. “Chet, my boy, we have a job for you.”
His plump friend looked up warily. “Take it easy,” he said. “I’m not over yesterday’s job yet.”
“All you need is a wrist watch,” Frank said. “You check around four o’clock this afternoon and if we aren’t back by then, you head for the nearest telephone and inform Chief Collig.”
Joe explained what the day’s plan was and quickly told Chet how to reach the entrance to the tunnels so that he could lead the police if necessary.
“Meanwhile, maybe you could help the soundmg crew,” Bob said. “The electronic equipment should be here in a few hours.”
“Okay,” said Chet. “That sounds safe enough.”
“I’d like to give the crew instructions before we head back to the summit,” said Bob, and the others walked down toward the men’s quarters with him.
Going down the slope of the reservoir, Frank noted that the hard ground underfoot was covered with the stumps of bramble bushes. Nearby was the large patch of heavy shrubbery left by the clearing crew. The water had risen as usual, covering part of the bushes. Frank paused and gazed at them thoughtfully.
“No use looking at that,” Dick said gloomily “We’ve prodded it a thousand times, I guess. There’s nothing but solid rock underneath.”
“I’ll bet it’s brambles,” said Frank, “like the rest of the stuff that was cut down around here.”
“So what?” said Chet. “With solid rock underneath there can’t be a tunnel.”
But Frank was already striding across the slope. “I’m going to have another look,” he called back.
As the others followed, they saw Frank reach the shrubs and break off a piece.
When Joe trotted up, his brother held out the twig. “Brambles.”
The Hardys peered into the thorny bushes. “They’re not growing as close to the ground as they look,” Joe remarked. “We could crawl in underneath and check that stone, if you want to.”
“It’ll be a scratchy job,” Frank said, ‘but I think we’d better.”
He stooped and crept into an opening at the base of the bushes. Joe followed. To their surprise, if they kept low, the branches barely touched them.
Inside the bramble patch it was dim, but sunlight filtered through and dappled the steep slope. A foot or so below them, amid the dark branches, the water lapped softly. Near the center of the bushes, they came to a huge slab of rock resting against the hillside with its base hidden in the water.
Suddenly Frank gripped his brother’s arm and pointed to the top edge of the rock. A narrow opening lay just above it!
Quick examination showed other gaps between the slab and the hill. Behind the rock was an opening!
“The tunnel!” exclaimed Frank. “This must be it!”
“But how do you get in?”
The brothers pulled hard at the edge of the slab. Suddenly, with a swish of the water, the big stone pivoted out about a foot.
Hearts pounding, the boys gazed into a dark tunnel with water gleaming on the bottom.
Joe gave a low two-toned whistle which Chet knew as a signal and in a few minutes the others stood with the Hardys at the mouth of the channel.
Bob and Dick could hardly keep from shouting for joy, but all remained silent.
They shone their lights into the narrow opening and saw that the gap behind the stone was roughly twelve feet high by six feet wide. Four feet above their heads was a narrow wooden catwalk built on supports which rested on the tunnel bottom. Just inside the entrance was a crude set of wooden rungs leading up to the catwalk.
Suddenly from deep inside the mountain came a high-pitched cry for help. The boys froze as it quavered and died. Once more it came. Then silence. The listeners exchanged anxious looks. Had it been Dr. Foster?
Frank’s eyes narrowed with decision. “Chet,” he said crisply, “you drive to the nearest phone and call Chief Collig. Tell him the rescue won’t wait till tomorrow. We’ll meet you and the police at the shack in two hours.”
“Take the convertible,” put in Joe.
“Meanwhile we’ll case the layout,” said Frank, “the way Dad asked us to.”
“Okay,” said Chet, and promptly started crawling out of the shrubbery. “Good luck,” he called back hoarsely as the others began climbing the ladder to the catwalk.
They saw that the side walls of the tunnel were made of shale, clay, and limestone. The dim light coming through the narrow opening behind them enabled the four explorers to see for a distance of several feet. But directly ahead the tunnel turned sharply and was lost in darkness.
The boys waited on the catwalk while Bob, who was last, reached out and easily pulled the big stone shut again. “It’s balanced on a pivot,” he thought.
Then they flicked on their flashlights and cautiously followed Joe, who was in the lead.
At the first turn he stopped. “Don’t need lights. Lanterns ahead,” he whispered to Frank, who passed the information down the line.
Walking under the flickering oil lanterns which had been strung along the passage, the boys felt keenly the danger of their position. Suppose someone came toward them around the next bend or into the tunnel from behind? There was no place to hide!
Hearts pounding, they rounded the second bend and stopped. “The lock!” Dick whispered.
Before them was a crude wooden structure nearly as high as the catwalk. It had two doorlike wings made of planks which met in the center. When the wings were closed, as they were now, the water was impounded. Behind the lock, the ditch was dry.
“There’s the gadget that operates it,” Bob whispered. He indicated an iron wheel at the side of the tunnel. It resembled the brake wheel of a railway freight car.
The four continued quietly along the wooden walk. Suddenly, when about to turn another bend, they heard footsteps approaching. The searchers stopped dead.
“Into the ditch!” Frank exclaimed softly, and swung himself down into the channel. Noiselessly the other three did the same. They flattened themselves against the rock wall under the catwalk. The footsteps came nearer and passed overhead.
The boys peered out and saw the man’s back in the light of a lantern. Sailor Hawkins! Briefly he inspected the lock, then returned along the catwalk. The four lifted themselves out of the sluiceway as soon as the old seaman had disappeared.
“That cavern where the men hide out can’t be far ahead!” Frank whispered excitedly.
He and his companions moved forward again. In a few moments they came to a small cave on the left. Joe poked his head in for a look around, but withdrew it with a start.
“Skulls!” he whispered. “The hermit’s supply room!”
Finally the boys and the engineers reached a cleft in the rock wall of the passage. Its floor, starting on a level with the catwalk, sloped upward for several feet. Then the crack expanded into a deep cavern, dimly lighted by lanterns.
From the darkness of the cleft, the four could see another fissure which slanted u
pward into the far wall of the big chamber.
Frank pointed to it. “That shaft must be the one which leads to the fork,” he whispered. On one side of it was a kiln and on the other a workbench. Stacked against the wall were boxes of supplies and across the chamber was a group of cots.
“Quiet!” Bob warned. “There’s a man!”
From an opening in the right wall strode Sailor Hawkins. He was carrying a plank, which he took to the bench and began sawing. The blade bit into the wood with swift, efficient strokes, and the boys observed that the seaman was cutting a board the same length and width as the planks in the lock.
“I’ll bet Hawkins built the lock,” Bob whispered.
“Look!” Frank whispered. “Here comes the hermit!”
The gaunt figure was staggering down the shaft from the mountaintop, his arms laden with split cordwood. He dropped the wood on the floor and walked to one corner of the room, where he sat on a box and leaned against the rock wall.
“Look!” Joe whispered, and pointed to the opening from which Hawkins had come.
A frail, slightly stooped man with white hair stood there uncertainly. Then he walked to the kiln, opened the oven, took out something and examined it. Beside the kiln stood a wheelbarrow, heaped with what looked like mud.
The hermit stood up and approached the old man in a deferential manner.
“That must be Dr. Foster!” Frank said in an excited whisper.
Joe nodded. “What’s he doing?” he asked.
Frank shook his head, and Bob whispered back, “I don’t know, but it looks as if he’s testing something in the kiln—maybe that mud.”
“Perhaps the gang believes there are mineral deposits in the valley,” Frank said softly. “No wonder they don’t want the water to rise there.”
“Think Foster is a member of the gang?” Dick asked.
“I doubt it,” Frank replied, keeping his voice down. “He doesn’t look like the sort of man who would willingly get involved in anything crooked.”
The fire door below the kiln had been opened, and the man of the mountain was stoking it with wood. A cloud of smoke poured from the galvanized-iron stack which led from the kiln into the shaftway beyond.
The Secret of Skull Mountain Page 10
