“Any word from Dad?” Frank asked.
“No,” Mrs. Hardy replied. “But we should hear something soon.”
Joe questioned Aunt Gertrude about the Entwistle mansion. She said it was supposed to be deserted. “A shame, too, since it's such a beautiful place. One of our Society members hinted that there might be some valuable pieces in the house, so well hidden the executors of the estate didn't find them. He said Mr. Entwistle was a queer old duck. There's even talk that tramps stay there sometimes.”
After dinner Frank and Joe decided to ride out to the Entwistle mansion and look around.
“Maybe we can find out if there's anything to the talk about tramps,” said Frank as they drove along the detour road toward the old estate.
“Yesâ” Joe began, then broke off as the noisy approach of a motorcycle reached his ears. The next moment he exclaimed, “Hey, Frank! That sounds like the Kesselring!”
His brother listened intently. “You're right. Hope he comes this way.”
But the Hardys were disappointed when the sound of the motorcycle grew fainter.
“He must have turned down a side road,” Joe said. “Let's try to catch up with him.”
Frank was about to agree when both boys saw something that made them gasp.
“That red glow in the sky!” Joe exclaimed. “It's right where the Entwistle mansion is!”
“The place must be on fire!” cried out Frank, stepping harder on the accelerator.
Soon they came within sight of the grounds. On a knoll stood the huge house. One wing was a mass of flames!
“We must get the fire department here before the whole place goes up!” said Frank.
He backed the car around, and in a few minutes the boys reached a farmhouse, where they put in a call to Bayport reporting the fire.
Then they sped back to the scene of the blaze. As they got out of the car, they heard sirens wailing. Minutes later several fire engines screamed to a halt before the burning mansion. Shouts of firemen filled the air while they fought to restrict damage to the wing that was being consumed.
Finally, after a half-hour battle, the flames were quenched and the bulk of the big house stood unscathed. Chief Tally, who had been investigating the charred ruins, returned to his car. A good friend of the Hardys, he greeted the boys with a weary smile. Frank told him they had heard that articles of value might be hidden in the house.
“Could be,” the fire chief said. “We suspect an intruder was ransacking the place and dropped a lighted cigarette.”
Joe told him of hearing a motorcyclist racing away from the vicinity of the Entwistle place, “He might be the one who was here,” he said.
Chief Tally smiled. “You boys are always on the job but this is the quickest I've ever received a clue.”
Frank then told him about the man on the Kesselring motorcycle who had nearly run them down. “The machine we heard tonight had the same kind of roar,” he said.
“Thanks for the information.” The chief nodded, then turned to speak to two firemen who would remain at the mansion, and the boys drove home.
They slept well that night, but the ringing of the telephone early the next morning awakened them. By the time Frank reached the hallway to answer it, he heard his mother talking on the extension in her bedroom. The door was open and she waved him in.
“Fenton, here's Frank now,” she said. “You tell him.” She turned to her son, excitement in her eyes. “That man Bowden is a fake!” she announced.
CHAPTER IV
New Tactics
“DAD!” Frank called into the phone. “How are you? ... That's good. What's this about Bowden?”
“The man isn't known here in Tampa, Frank. And no pirate ship with a demiculverin has been entered in the Gasparilla event.”
Frank whistled. “I've been suspicious of Bowden from the start. But you don't think we should stop looking for the cannon, do you?”
“Certainly not. Apparently there's a mystery connected with it that's worth checking into. Furthermore, I'm working on a swindling case that Bowden may be mixed up in. I think he's using an assumed name.”
“Shall we notify the police or shadow him ourselves?” Frank asked.
Mr. Hardy's advice was to do neither. Instead, he suggested that his sons continue to be friendly with Bowden.
“It's the best way to get at the truth,” he said. “And let me know if I can be of any more help. I'd like to speak to your mother again.”
Frank dashed back to the boys' bedroom and told his brother the news.
Joe hopped out of bed. “Frank, this is going to be fun. We pretend to play along with Bowden, but all the time we're trying to find out what he's up to!”
Frank stared out the window. “I'm wondering which problem we should tackle firstâBowden or the motorcyclist.”
“Let's combine the two in one trip. We'll go to the motel first, then on to Delmore.”
During breakfast with Mrs. Hardy and Aunt Gertrude, the young detectives told about their plan, and as soon as they finished eating, they started for the door. Aunt Gertrude stopped them and handed Joe a book.
“You might as well employ your time profitably while you're riding along. Joe, read this aloud while Frank drives.”
Her nephew glanced at the book. “Why, this is great, Aunt Gertrude ! It tells about the various types of old artillery. Where did you find it?”
“In your father's library.” She chuckled. “I thought it might give you a clue to that demiculverin you're trying to locate.”
The boys said good-by to their mother and aunt.
“We'll be home in time to move those cutlasses,” Frank promised.
As they drove off, Joe turned to a section on culverins and read aloud:
“ âIt derives from the Latin word colubra (snake) . Culverins were highly esteemed on ac. count of their range and effectiveness of fire. Their thick walls, long bores, and heavy powder charges made them the most deadly of field-pieces.' ”
“And Bowden is telling us he wants to mount a fieldpiece on a pirate ship!” Frank muttered,
Joe shrugged. “That's what he's telling us. I wonder what he really wants the cannon for.”
Half a mile farther down the highway, Frank pulled up in front of the Garden Gate Motel. The clerk told them Bowden was in Room 15.
“There it is!” Joe said, spotting the number. He knocked on the door. There was no answer.
“Hey, this looks like a note,” Frank said, eying a paper pinned below the doorknob.
“Maybe it's for us,” Joe suggested.
Frank read the message aloud:
“ âBowden! Clear out before it's too late!' ”
“Wow! I Our friend has an enemy!” Joe remarked. “Do you think this will drive him away?”
Frank shook his head. “I doubt it. He wants that cannon too badly. Well, let's go to Delmore and stop here on our way back.”
The detour they had to make took the boys past the farm of their friend Chet Morton. Chet was eighteen, roly-poly, good-natured, and loved to eat. Solving mysteries with the Hardys always gave him the jitters. Despite this, he was a loyal assistant and on more than one occasion had rescued them from dangerous predicaments.
“Let's stop a minute,” Joe suggested, seeing Chet's sister Iola near the swimming pool.
Frank grinned knowingly. Joe and Iola dated frequently. He pulled into the driveway. The boys got out and walked toward the pretty dark-haired girl.
“Hi! she said.
“Hello, there,” Joe said. “Where's Chet?”
Iola pointed to the pool. Their stout friend was underwater, wearing flippers and a snorkel. He traveled slowly, the snorkel moving like the periscope of a miniature submarine.
“Ahoy!” Joe yelled as they ran to the water's edge.
Chet continued moving about like a walrus. But finally he emerged and removed the face mask and flippers.
“Hi, fellows!” he called. “I'm having a hard time learning this. Can't get down deep enough.”
“What's the trouble?” Joe asked. “That extra fat you carry around make you too buoyant?”
“Now, listen here,” said Chet, “just because I know good food when I see itâ”
Then he changed the subject, telling them he was going to take lessons in skin diving from the same man who had taught the Hardys.
“Swell,” said Joe.
“I can't start, though, until I earn enough money to buy all the gear.”
“Don't let that worry you,” Frank spoke up. “I'll lend you my outfit.”
“Thanks. And now bring me up to date on everything that's happened lately.”
The Hardys had just finished telling Chet and Iola about Bowden, the mysterious cyclist, and the skin-diving attack, when they saw a car driving in. At the wheel sat Callie Shaw, an attractive girl with blond hair and sparkling brown eyes. She was Iola's friend and Frank's regular date.
Callie alighted, and after greeting everyone, said, “I'm glad you're all here. I wanted to talk over plans for our Fourth-of-July beach party. Tony Prito is coming with us too.”
Tony, a schoolmate and fellow athlete at Bayport High, had been through many adventures with the Hardys.
“Let's have a clambake like last year,” Chet suggested.
Suddenly Frank grabbed Joe's arm. “Look over there! A man's spying on us!”
He had seen someone peering from behind a tree near the road. The quick glimpse of a black jacket led Frank to believe that the man might be the wanted motorcyclist!
“Come on, Joe!” he whispered, starting to run.
Instantly the man raced off. Having the advantage of a head start, he reached a parked motorcycle, jumped on, and sped off.
From the silhouette of the rider and the sound of the motor, there was no doubt in the Hardys' minds as to the spy's identity.
“It's the guy we're looking for!” Joe exclaimed.
Together, the Hardys ran back to their car and hurried after the suspect. They had covered nearly two miles before they caught sight of him. Reaching the crest of the next slope, he looked back. Seeing that his pursuers were getting closer, he revved his machine and shot into the curving downgrade.
“Faster!” Joe urged. “He's getting away from us!”
Their car whined around the curve in hot pursuit of the Kesselring. Once again they came to a straight stretch of road, but there was no sign of the motorcyclist.
“He turned off!” Joe said in disappointment.
“He must have swung into that dirt road we just passed. Let's go back!” Frank exclaimed.
Screeching to a stop, he made a U-turn and sped to the side road. They plunged onto the rough, narrow, dirt lane. Fresh motorcycle marks were clearly evident. Dust filled the air, choking the boys as they sped along.
“Stop!” Joe cried suddenly. “The track ends here!”
Frank parked the car and locked it, then both boys ran back to the point where the tracks turned off into the pine woods.
“He couldn't go very far through here on his motorcycle,” Frank said as they pressed on excitedly.
“You're right!” Joe whispered. “Look!”
CHAPTER V
The Stakeout
AHEAD of the Hardys in the deep woods stood a cabin. The Kesselring was parked near the front door.
Quietly the boys moved into a position giving them a better view of the building.
“Shall we go in?” Joe asked in a low voice.
“I'll go,” Frank replied. “You cover the rear, okay?”
“Roger.”
Frank walked cautiously toward the front door. It was open and the place appeared to be deserted. The young detective strode inside. No one was in sight!
Frank went out and joined Joe. “He gave us the slip!” he said in disgust.
“But not for long. He'll be back for his bike,” Joe said. He suggested that they pretend to leave, then double back and stay in hiding until the man returned.
“Suppose he finds out our car is still on the road,” Frank said.
“We'll have to take that chance,” Joe declared.
The boys walked off in the direction of their convertible, but five hundred feet beyond the cabin they turned and quietly made their way back. Hiding behind clumps of brush, they began their vigil. Fifteen minutes went by. Thirty.
Suddenly the quiet of the morning was broken by the crackling sound of footsteps.
The Hardys tensed. Someone was approaching from behind them. They shifted their position.
“Get ready, Joe,” Frank whispered.
The steps grew louder and a tall figure appeared through the brush. The boys pounced on the newcomer and all three fell hard to the ground.
“Bowden!” Joe gasped.
“For heaven's sake, what ails you guys?” the man stormed, picking himself up.
“We thought you were someone else,” Joe replied.
“Why are you here?” Frank asked, wondering if Bowden had a rendezvous with the occupant of the cabin.
“I might ask you the same thing,” Bowden retorted.