The shutter of Chet"s camera clicked and clicked again. Suddenly, one of the men who rose to get a another piece of wood for the fire, caught a glimpse of the big blimp out of the corner of his eye. He let out a yell that carried to the soaring aircraft.
The two other men gave a start, whipped out handkerchiefs to cover their faces, and dashed into the bushes. But not before diet had snapped another picture.
"What do you want to do now?" asked the pilot.
"Hurry back to the plantation," Frank said. "We"ll drop a note to General Smith."
With a roar, the motors started again and the blimp picked up alt.i.tude. But as it did, one of the men on the ground ran into the clearing with a rifle.
"He"s going to shoot!" Joe shouted.
"Little harm if he punctures the bag," the pilot said calmly. "Helium won"t burn."
"But suppose-"
Frank"s remark was cut short as the rifle spoke and 185 a bullet struck home. The pilot gave a groan of dismay. The starboard motor began to cough.
Immediately Crandall tried to coax it back to its normal, pulsating drone, but his feverish manipulations failed. The motor sputtered. Then the propeller feathered listlessly, and all at once a tongue of flame leaped from the cowling.
Crandall shouted, "He hit a gas line!"
CHAPTER XXIII.
The Final Clue.
A searing blast of black smoke and crimson flame shot past the windows of the control car. At the same time automatic fire extinguishers on the engine sprayed foam onto the blaze, but they failed to put it out.
"The fire"s spreading!" Frank shouted to the pilot, who was diving toward the ground, using the other motor.
"Here! Take the wheel!" The pilot beckoned to Chet.
"I-I never flew a blimp!"
"Just hold her steady." Crandall slipped out of his seat and pushed Chet into it.
The pilot rushed back to the Hardys jus* in time to see flames break into the control car.
186.
187 "We must get out of here quick!" he shouted. "If the fire reaches the gasoline tanks, we"re goners!"
"Where are they?" Frank"s voice sounded terse.
"There." Crandall pointed to a storage tank toward which the red tongues of flame were licking. He bent over a locker on the side of the car. Reaching inside, Crandall pulled out a wire contraption.
"Lucky we have a Jacob"s ladder," the pilot said. He slid back the outer door and attached one end of the ladder to specially built hooks in the floor. "Climb down while I bring her lower."
To hasten the descent, Crandall reached up and turned a big valve.
"Letting out some helium," he explained hurriedly, then went to relieve Chet at the controls.
As the blazing blimp glided earthward over the plantation, Joe climbed down the ladder speedily. When his legs brushed the top of a tall tree, he let go. Frank shouted to Chct: "You"re next!"
The stout boy obeyed without question, knowing it was a matter of life or death. The fire was roaring louder as it ate its way nearer and nearer to the auxiliary fuel tank.
"Let go!" Frank shouted as the blimp crossed a small pond.
Chct released his tenacious grip. The plump 188 youth looked like a miniature blimp himself as he sailed through the air and hit the pond with a tremendous splash. Then he bobbed to the surface and started swimming for sh.o.r.e.
"Come on, Crandall!" Frank shouted.
"The pilot goes last," the young man insisted.
Frank descended, with Crandall right behind him. By this time the blimp was directly over the grounds of the plantation mansion. Frank"s feet were barely ten feet above ground.
He let go at about the same time Crandall did. Together, they fell tumbling into the tall gra.s.s, rolling head over heels and coming to an abrupt stop near the ruins.
The blimp fell to the earth like a stricken giant some hundred feet away. A belch of red flame shot high into the air as the fuel tank exploded. With a great whoosh, whoosh, the blimp was the blimp was enveloped in a sheet of fire.
Crandall limped up to Frank. "I"ve had many close ones," he said, "but this was the closest."
"I"m sorry your blimp"s gone," Frank consoled him.
Crandall managed a half-smile. "It"s covered by insurance," he said. "I"m just glad we"re safe; that is, if your brother and Chet are all right."
The two appeared in a few minutes, none the worse for their experience. General Smith ran up 189 to the group, pale and excited. "Thank goodness you all got out alive."
"Whewl I w-wouldn"t like to do that for a 1-living," Chet stuttered.
Frank introduced General Smith to the pilot, who said he ought to get to Centerville at once and report the incident to government authorities. "Serious business, shooting down an aircraft," he said grimly.
"We"ll take you to town," Frank offered.
As they made their way to the coupe, Crandall asked if they had any idea who had fired upon them, "We think he"s a criminal who calls himself Dr. Bush," Joe answered. "He"s been bothering us for some time."
"Well," Crandall said after a pause, "Bush is in real trouble now. He can"t go around shooting down blimps in peacetime and expect to get away with it."
The whole group went to the police station. The chief said he would relay the news to the state police, and a determined search would be made for the men responsible for the near deaths of the boys and the pilot. The Hardys would have liked to go with them on the hunt, but General Smith would not hear of this.
"You were up all last night," he said, after they 190 had bidden Crandall good-bye. "1 doubt that Bush and his gang will be caught."
"Why not?" diet asked.
"They"ll get as far away from this area as they can."
"That suits me." Chet beamed and turned to the Hardys. "Tomorrow you fellows can find the right tunnel without those guys shoving guns in your backs."
Claude was waiting for them with a sumptuous meal. It was not Chet alone who came back for third helpings of pompano and fried tomatoes. Frank and Joe"s recent experience had given them ravenous appet.i.tes.
Chet had planned to take his important roll of films to town for developing after dinner, but he fell asleep in an easy chair. General Smith and Joe discussed the mystery, while Frank for the hundredth time looked over the coded message found in the ammunition box.
Finally he said: "There"s one symbol on this sheet we"ve never tried to solve, and it might be the connecting link in the message."
"What"s that?" Joe asked.
"The strange-looking tree. You said you never saw one like it, General Smith?"
"1 can"t recall ever having seen one."
Frank became silent again, but in a few minutes 191 he remarked, "Do you suppose there are any old-timers in town who would remember the plantation before it was ruined?"
As the general pondered, Claude came to say good night. "I beg yo" pardon, Mr. Frank,"
he said, "but I believe Reverend Colts, the pastor of my church, could help you."
"That"s fine. Thank you, Claude. We"ll call on him in the morning."
The Hardys" first stop in town the following day, however, was the jail. The keeper told them the prisoner they had caught still refused to talk, and was being held temporarily for carrying a gun without a permit, and on various other counts.
"We"ll detain him as long as possible," the jailer said. "Maybe he"ll get tired of keeping quiet."
The boys also learned there was no news of the wanted gang. While Chet went to the stationery store, the Hardys and General Smith called at the home of the minister. The kindly, middle-aged Negro answered their knock. The general introduced himself and asked if the pastor knew of anyone still alive who could tell them about the Smith plantation before the Civil War.
"Yes, sir, I do," the pastor replied. "Benjamin Berry. He lives in an old people"s home.
As a boy, he had worked for Mr. Beauregard Smith."
192 The boys and the brigadier thanked the minister and drove to the home, located a mile away. An attendant pointed out old Ben, who was rocking on the side porch of the red-stone building.
"How do you do, Ben," said General Smith, smiling and telling the man who he was.
"Meet some friends of mine."
The old man arose. To their questions he said he had served the Beauregard Smith family long after the emanc.i.p.ation. He was delighted to talk about his boyhood days on the plantation. After a few minutes, General Smith steered the conversation around to the lost tunnel.
"Did you ever hear of an old a.r.s.enal on the plantation?" the brigadier asked.
Ben shook his head. "No, suh."
"Ever see a tunnel, or any other hiding place?"
The old man took up a tall cane resting beside his chair, folded his bony hands over its head, and leaned his chin upon his gnarled knuckles.
"I"m tryin" to think, General." He paused. "No. I disremember any tunnel, but I knows my grand-pop was scared o" the woods along the run."
"Why?" Joe was first with the question.
"He once saw Mr. Beauregard swallowed right up by the earth. Grandpop figgered they was some sort o" hole that n.o.body but ol" Ma.s.sa Smith knew about/"
193 "That may be just what we"re looking forl" Jos burst out. "Where was the place, Ben?"
"That I don" know zactly. Some place along Rocky Run."
"There"s another question we"d like to ask you, Ben," Frank spoke up. The boy reached into his pocket and pulled out a drawing of the tree as it had appeared on the coded message. "Ever see a tree like this?"
Ben carefully adjusted a pair of gold-rimmed spectacles on the bridge of his nose. After studying the tree a moment, he smiled.
"Well ah declare! Ah haven"t seen a Frar.klin tree for many, many a year."
"A Franklin tree?"
"Ol" Ma.s.sa Smith planted a lot ob dem along Rocky Run. They was his favorite tree!"
Old Ben was a little vague about the tree except that it "smelled purty." Excited over the information, Frank asked the attendant if he might use the home"s telephone. He was taken to an office, the door was closed, and he put in a call to the State College Botany Department. The man who answered was an affable a.s.sistant professor.
Frank informed the man what the old Negro had told him, and asked, "Is there such a thing as a Frank-Sin tree?"
194 "Surely is."
The a.s.sistant professor said the tree was discovered first in the Carolinas in the sixteen hundreds. Then all track of it was lost, and the tree was not found again until the middle of the nineteenth century, when it became quite popular, and was named for Benjamin Franklin.
"The tree," the man added, "stands from fifteen to twenty feet high, has a leaf like a magnolia, and bears fragrant, white blossoms." Then he concluded, "The trees are still rare, because they"re not a very strong variety. Does that answer your question?"
Frank said it did, and thanked his informant. He hurried back to Joe and the general, and they returned to the center of town, diet, who had left his film to be developed, joined them and heard the latest news.
"Let"s get out to Rocky Run as soon as possible," Joe said eagerly.
"Not me," diet spoke up. "I have a hunch that this lime my pictures are going to solve the mystery. The man said he"d have "em ready by twelve o"clock, so I"m hanging around here to get "em."
General Smith was about to climb into the car with the Hardys when Claude came hurrying along the street, waving for the ollicer to wait a minute.
195 "A long-distance call came in for you, sir," he reported. "Very poor connection, but the telephone company said the party would call again about twelve. It"s very important, and will you please be there."
As the Hardy boys drove off, they wondered if the call might have anything to do with their case. But the thought was driven from their minds as they eagerly talked about the clue of the Franklin tree which they hoped would lead them to a secret underground spot and the buried treasure.
In the meantime, Chet, to while away the time, walked around the town, had an ice-cream soda, and bought some scenic cards of Centerville to send home. At quarter to twelve his pictures were ready.
"They"re very interesting, son," the shopkeeper remarked. "Where"d you ever snap "em from?"
The air.
Chet pulled them from the envelope eagerly. One look and he gave a shout.