crack had appeared in the bolted door.
One of the men outside yelled, "A couple more blows and we'll be in."
Frank dug furiously. Suddenly his shovel opened up a small hole in the crumbly dirt. Joe
scooped away with his hands. Finally there was a space big enough for the boys to squeeze
through. Without hesitation, Frank wriggled in, then Joe.
From behind them came a tremendous crash and the sound of ripping wood. Markel's voice
shouted, "Into the tunnel! After 'em!"
The Hardys heard no more as they pushed ahead on hands and knees into the damp darkness
of an earthen passageway.
Joe was about to call out to his brother when he became aware that someone was crawling
behind him.
"No room here for a knockdown fight," he thought, wondering if the pursuer were armed.
The young detective scrambled on as fast as he could in the narrow, twisting tunnel. He
managed to catch up to Frank, and with a push warned him to go at top speed.
"Somebody's after us!" Joe hissed. "If only we can outdistance him!"
The underground route was a tortuous, harrowing one. The Hardys frequently scraped knees
and shoulders against sharp stones in the tunnel floor and walls. They had held onto their
flashlights, but did not dare turn them on.
"This passageway is endless!" Frank thought. The close, clammy atmosphere made it
increasingly difficult for him and his brother to breathe.
Joe thought uneasily, "What if we hit a blind alley and are stuck in here?"
The boys longed to stop and catch their breath, but they could hear the sounds of pursuit
growing nearer, and forced themselves onward faster than ever.
Frank wondered if Chet and Tony had seen the men enter the mill and had gone for help.
"We'll need it," he thought grimly.
Suddenly the brothers came to another turn and the ground began to slope sharply upward.
"Maybe we're getting close to the end," Frank conjectured hopefully.
Spurred by possible freedom, he put on a burst of speed. Joe did the same. A moment later
Frank stopped unexpectedly and Joe bumped into him.
"What's the matter?" he barely whispered.
"Dead end," reported his brother.
Squeezing up beside Frank, Joe reached out and touched a pile of stones blocking their path.
The boys now could hear the heavy breathing of their pursuer.
"Let's move these stones," Frank urged.
Both Hardys worked with desperate haste to pull the barrier down. They heaved thankful sighs
when a draft of fresh air struck their faces.
"The exit!" Joe whispered in relief.
The brothers wriggled through the opening they had made and found themselves in a rock-
walled space.
"It's the cave by the river, Joe!" Frank cried out. "Someone put back the rocks we removed!"
The boys clicked on their flashlights and started toward the entrance of the cave.
"We beat 'em to it!" Joe exclaimed.
"That's what you think!" came a harsh voice from the entrance.
The glare from two flashlights almost blinded the Hardys. Docker and Markel, with drawn
revolvers, had stepped into the cave.
CHAPTER XX
Solid Evidence
FOR a second the two armed men stared in disbelief at Frank and Joe. "The Hardy boys!"
Docker snarled. "So you're the snoopers we've trapped!"
There was a scuffling in the tunnel behind the boys. A stocky man, huffing and puffing, emerged from the tunnel. The Hardys recognized him instantly: the counterfeit passer, Victor Peters.
The newcomer gaped at the Hardys. "What are they doing here?"
"A good question!" Markel snapped at his accomplice. "You told us on the two-way radio you'd locked 'em up with the truck."
Peters whined, "I did. They must've broken out."
"Obviously." Docker gave him a withering look.
Frank and Joe realized that Peters had not returned to the old farmhouse.
Docker whirled on them. "How did you escape?"
The boys looked at him coldly. "That's for you to find out," Joe retorted.
"It's a good thing Markel and I decided to head 'em off at the cave," Docker added angrily.
"Otherwise, they would have escaped again."
The Hardys could see that the men were nervous and edgy. "I'm not the only one who made a mistake,"
Peters growled. "I told you a couple of days ago to get rid of that kid Ken when these pests started asking about him, and then found the tunnel. We could have thrown 'em off the scent!"
While the men argued, the Hardys kept on the alert for a chance to break away. Markel's eye
caught the
movement, and he leveled his revolver. "Don't be smart!" he ordered. "You're covered."
Peters continued the tirade against his confederates. "Docker, you should've finished these Hardys off when you put 'em in the boat that night! And you"-Peters turned on Markel- "you could have planted a dynamite charge in their boat instead of just monkeying with the
throttle."
The Hardys, meanwhile, were thankful for the precious minutes gained by the men's
dissension.
"Tony and Chet might come back in time with help," Joe thought.
Simultaneously, Frank hoped that Ken Blake had carried out his whispered instructions.
Docker glanced nervously at his watch. "Blum ought to be here," he fumed.
"Who's Blum?" Frank asked suddenly. "One of your counterfeiting pals?"
Docker, Markel, and Peters laughed scornfully. "No," said Markel. "We're the only ones in our exclusive society. Paul Blum doesn't know anything about our-er-mill operation, but it was
through him we got the jobs at the gatehouse. The whole deal really paid off double."
Docker interrupted him with a warning. "Don't blab so much!"
Markel sneered. "Why not? What I say won't do these smart alecks any good."
Joe looked at the guard calmly. "Who paid you to let the green panel truck into Elekton?"
All three men started visibly. "How'd you know that?" Markel demanded.
"Just had a hunch," Joe replied.
The former guard regained his composure. "We'll get our money for that little job tonight."
Frank and Joe felt elated. Paul Blum, whom these men expected, must be the sabotage
ringleader! "So that's what Markel meant by the deal paying off double," Frank thought. "He and Docker working the counterfeit racket on their own-and being in cahoots with the
saboteurs."
Frank addressed Markel in an icy tone. "You call blowing up a building a 'little job'?"
The counterfeiters' reactions astonished the Hardys. "What!" bellowed Markel, as Docker and Peters went ashen.
Joe snorted. "You expect us to believe you didn't know explosives were in that truck?"
Victor Peters was beside himself with rage. "Fools!" he shrilled at Docker and Markel. "You let yourselves be used by saboteurs? This whole state will be crawling with police and federal
agents."
The gatehouse men, though shaken, kept their revolvers trained on the Hardys. "Never mind,"
Docker muttered. "Soon as Blum shows up we'll get out of here and lie low for a while."
Frank and Joe learned also that Docker and Markel actually were brothers, but the two refused
to give their real names.
"You, Docker, are known as The Arrow, aren't you?" Frank accused him.
"Yeah. Next time I'll use you boys for targets!" the man retorted threateningly.
The Hardys kept egging the men on to further admissions. Docker and Markel had been
approached several months before by Blum who tipped them off to good-paying jobs at the
Elekton gatehouse.
Docker had cleverly forged references and identification for Markel and himself.