"1 have an idea," Frank declared, "that the bank"s gold, the Smith treasure, and a load of old cannon b.a.l.l.s are lying side by side in some secret tunnel. Now we"ve got to start some real digging."
"The sooner the better," said Joe.
"I"ll get a couple of laborers to help us," General Smith offered, "and we"ll dig this place up till we find that tunnel!"
173 The eastern sky was faintly pink as the group gathered up the papers and set off for ihe car. Back home they bathed, ate, and caught a few hours sleep. Then the general made some telephone calls to arrange for two workmen in Centerville to help with the digging on the plantation.
Chet, who was the last one awake, was agog over the news. Though his leg was stiff and sore, he insisted upon going with the group to hunt for the tunnel.
Directly after breakfast, they set out for town to pick up the two workmen. On the way the Hardys asked the officer where he thought the tunnel was likely to be.
"I imagine it led from the cellar of the mansion to one of the other buildings. Or it might have been an underground entrance for slaves coming to the house."
"In that case, the opening would have been somewhere in a garden," Frank mused.
A few minutes later they picked up the laborers and drove to the old plantation.
"I want you to dig in the ruins of this mansion," the general told the men. "We think there may be an old tunnel here somewhere."
The laborers plied picks and shovels, and the boys pitched in to aid in the stubborn task. Together 174 they dug in the hot sun until late in the morning when Joe"s pick struck a layer of bricks.
"Hand me a crowbar!" he called up to Chet, who *was sitting on a pile of stones watching the work.
His friend let down the long bar. Joe battered the bricks at his feet. Suddenly they caved in and the crowbar plopped into a deep hole.
"I"ve hit a tunnel!" Joe cried.
CHAPTER XXII.
A Prisoner.
the opening he had made in the earth was large enough for Joe to slip through. He beamed his flashlight below. Definitely there was an underground pa.s.sageway.
"Lower me down here, Frank," he called excitedly.
Frank and Joe interlocked their wrists, the older boy easing his brother down into the black hole.
"Okay," Joe called hollowly in the vault below. "I"ve hit bottom. It"s solid."
"What do you see?"
Joe flashed a beam around the moss-covered walls of the tunnel.
"Nothing here," he called. "But I"ll find out where it goes."
"Wait for me," Frank said.
In a moment he too was in the tunnel. The boys turned left and walked gingerly in the bricked pa.s.sageway toward what once had been the opening into the cellar of the mansion.
The entrance was sealed up by a heap of stones which apparently had fallen down from the old foundation.
"This is as far as we go in this direction," Joe said. "Let"s find the exit."
Picking their way along the dark tunnel, the boys walked nearly two hundred feet. There was not a sign of any gold or any cannon b.a.l.l.s. Presently the pa.s.sageway started uphill.
"Here"s a dead end," Frank said as they came to a halt before a mound of earth.
"Must lead somewhere," Joe said. "I"m going to give it a kick." He sent his foot thudding into the soft dirt. "Look! I see daylight!"
Joe"s kick had opened up a slight fissure in the earthwork thrown up at the end of the tunnel.
"I"ll bet I could crash right through that!" Frank exclaimed. "It doesn"t look too thick."
He stood back a few feet, then ran forward, twisting around so that his shoulder hit the dirt wall with a solid impact. The end of the tunnel gave way and Frank went sprawling on the gra.s.s outside.
Joe quickly followed. When the boys" eyes became accustomed to the sunlight, they realized they 177 were at the foot of a little terrace in back of the ruins.
"This knoll probably was built just to conceal the opening to that tunnel," Frank remarked.
"And it"s concealing something else," Joe whispered excitedly. "Frank! Look at that guyl Where"ve we seen him before?"
Frank followed his brother"s gaze to a figure crouched behind a tree observing every move of the boys" companions. He was thin, and had a stubbly, gray beard.
"Joe," Frank said in an excited whisper, "he"s the guy who gave us phony directions to the museum."
"Let"s get him!" Joe cried.
He leaped toward the man, but in his haste stepped on a twig, which snapped with the sound of a revolver shot. The watcher looked around. When he saw Frank and Joe in pursuit, the man took to his heels like a flash.
Hearing the sound of flying feet, the others at the ruins turned in surprise to see the Hardys racing after a stranger.
"How the d.i.c.kens did they get out of that tunnel?" Chet spluttered.
As the laborers watched openmouthed, Frank and Joe sped after the fugitive, who seemed to be follow178 ing a familiar route. Though a swift runner, he was no match for the Hardys. In a few minutes they overtook him.
"Lemme go!" he cried loudly as the boys held on to him. "I ain"t done nuthin"!"
"Why were you spying on us?" Frank demanded.
"None o" your business what I do for the pro-" The man caught himself and refused to say another word.
"Pro?" Frank thought. "Could he mean professor?" There was one man in the gang whose name they had heard as Hank. On a hunch Frank said, "Better talk, Hank!"
Frank"s deduction evidently had been correct. A wild look came into their prisoner"s eyes. He made a desperate effort to escape, but the Hardys held him firmly, and ordered the man to precede them back to the ruins.
General Smith met the trio a distance away from the laborers. "Brought in a prisoner, eh?"
Frank whispered in the brigadier"s ear where they had seen him before. "I"m sure he"s one of the gang. He was watching us work."
The officer tried to make the man talk, but it was useless. He decided to turn the fellow over to the police at once. Since the Hardys wanted to investigate the tunnel farther, they remained at the 179 spot. Chet went along to Centerville as custodian of the prisoner.
Frank and Joe looked carefully at every brick in the old tunnel, but it was as bare of any treasure as a village sacked by an invading army.
"It"s evident this isn"t the tunnel Beaurcgard Smith meant," Joe said at last.
While the boys waited for General Smith, they discussed the mystery from every angle.
Perhaps now they would get a break, if the prisoner would confess. But once more luck was against them. The man, a stranger to the area, refused to divulge even his name, General Smith reported upon his return.
"Just the same, I think he"s one of the Bush gang," Joe declared.
"I don"t like Bush"s silence," Frank spoke up. "It"s kind of ominous, like a snake. I think we ought to checkmate him."
"Good idea," the general agreed. "But how?"
Frank mulled over the problem.
"The man we captured seemed to be heading for some spot. Perhaps Bush and his gang have a hide-out right under our noses."
"It would be mighty hard to ferret them out," the general said. "They"re probably in some secluded place where they"d have the draw on us.
180 If they"re in the timberland, it would take an arm, of men to beat the bush."
"Unless we got high enough to look down on "em," Frank suggested.
"That"s it!" Joe was excited. "We"ll fly over the woods."
"The noise of a plane would warn them to duck," the officer reasoned.
"We won"t use a plane," Frank declared. "We"ll get a blimp. We can shut off the motor and drift around. Is there an airport near here, General Smith?"
"Yes, a big one about twenty miles from Rocky Run. Why don"t you do it this afternoon? I think there"s been enough gold hunting for one day."
When they arrived home, Chet handed the Hardys a telegram. It said: GOOD CLUE BABY. WEST COAST SLIPPERY. DOWN SOON. DAD.
Chet grinned. "Gee, that sounds funny. I suppose it"s in code."
Neither he nor the general could make out the message, so Frank interpreted. "Baby Face is a slippery customer, probably from the West Coast."
"Wow!" Chet cried. "No wonder he"s handy with a gun!"
181 General Smith looked very serious. "You boys have done mighty well on this case, and have one prisoner. How about calling it quits? With the material you"ve already gathered, your dad should solve this mystery p.r.o.nto."
Joe frowned. "That"s just it, sir. We We want to solve it before he gets here." want to solve it before he gets here."
"Well, I"m all for you," the officer said. "You surely have opened my eyes. Didn"t know the younger generation had so much detective ability. We"ll get that blimp today. Call up, and make arrangements, Frank."
The boy contacted the airfield and talked with a young pilot who operated a blimp for advertising purposes. Most of his work was at night, so he readily agreed to the day job.
At four o"clock Frank, Joe, and Chet arrived at the airfield. By arrangement, General Smith was to post himself at the old plantation. If the boys found the location of Bush"s hide-out, they were to fly over the plantation and drop a message to the officer. He, in turn, was to get the local police to a.s.sist in the roundup of the criminals.
As they neared the airport building, Chet burst out, "Just the right kind of day for pictures. Maybe I can take some good ones from the blimp and sell them to a newspaper."
182 The Secret of ihe Lost Tunnel The blimp nestled alongside its hangar like a giant sausage. A young man came out the door as Frank parked.
"Got here in good time." He smiled at the boys, and introduced himself as Tom Crandall.
Frank explained his mission, saying they were going to look for a group of men believed to be in the woods near the old plantation.
"We"ll go up right away," Crandall said.
He climbed a steel ladder into the control car of the blimp. The boys followed. Crandall started the motor, the propeller raced to life, and the big craft lugged at the lines which held it to the ground.
"Okay, let "er go!" The pilot waved to two ground a.s.sistants, who released the lines, and the blimp rose into the air.
Frank sat in a bucket seat next to the pilot, with Chet and Joe directly behind. As the blimp glided over the irectops, Frank watched the pilot as he manipulated the controls.
"Where did you learn to fly these things?" Frank asked him.
"Navy." He grinned boyishly, turning his head to address Frank. "We"ll crisscross the area. Tell me when we get there."
It did not take the craft long to arrive over the old plantation, although Frank had asked that they 183 go slowly. Peering out the windows of the car, the boys saw General Smith far below, waving up to them.
"Here"s the place," Frank said, taking in the area with a sweep of his hand. "Go a mile or so north, then back again. Will you shut off the motor when we get over the middle of the woods?"
"Sure."
The boys" eyes were glued to the windows for a possible glimpse of anybody in the secluded area below. Chet fussed with his camera, getting the proper lens opening, then squinted down at the scene.
Suddenly Frank cried out, "Look! There"s smoke over there!"
Far ahead, and apparently rising from a clearing, curled a lazy wisp of smoke. Without being told, the pilot shut off his motors.
"Somebody"s down there, sure as shootin". We"ll pa.s.s right over them."
Tense with excitement, the boys waited for the blimp to drift slowly above the spot from which the smoke was rising.
"Can you bring her lower?" Frank asked.
The pilot nodded, then manipulated the tail of the blimp so that it nosed down. Barely above the treetops, he leveled off again. The smoke was 184 closer. Finally a clearing suddenly came into view.
Three men were huddled around a campfire, evidently preparing a meal. They were faced away from the blimp, so that they could neither be seen directly by the boys nor could they see the blimp bearing down upon them.