"You are right. It must have dropped out of my shirt pocket when I bent down to get something out of a toolbox. Incidentally, I was a prowler at your house twice."

"Did you ever shoot at the Hai Hauf" Hai Hauf" Joe asked. Joe asked.

Butler said, "I took a practice shot once."

Chin Gok broke in. "But our work is not finished. For my part, I haven't yet found the clue to the Hai Hau's Hai Hau's treasure, but I will! You will not stop me!" treasure, but I will! You will not stop me!"

"What do you mean? What are you going to do to us?" Chet quavered.

"Butler and Burns," Dr. Montrose spoke up, looking toward the two sham coastguardmen, "you tell them."

The one named Butler burst into harsh, mocking laughter. "See that pool? Well, that's where you're headin'. We're goin' to throw all three o' you boys, tied up just like you are, into this bottomless hole!"

CHAPTER XX.

Underground Battle.

unaware of the grim happenings under the cliff, two groups of the Hai Hau's Hai Hau's pa.s.sengers pa.s.sengers were thoroughly enjoying themselves. To pa.s.s the time, Biff, Tony, and Jim began searching the junk again for a clue to the treasure. After a dip in the surf, lola and Gallic strolled back to the wharf.

"Find anything?" lola asked.

"No," Biff replied.

"Let's all look," Gallic suggested. "Maybe we can surprise Frank and Joe with a clue!"

The five friends joined in the hunt. Tony perched himself in the bow, with one leg swung over the side. He scowled thoughtfully as his eyes roved the hull of the Hai Hau. Hai Hau.

Could the clue to the fortune be hidden somewhere on the outside outside of the junk? of the junk?

Absent-mindedly he pressed one of the gla.s.s eyes in the figurehead. To his surprise, it pushed inward! Tony gave a yell that brought the others running.

176.

177 A secret panel had slid open on the inner side of the bulwark!

"I've found somethingl" Excitedly he reached into the small compartment and pulled out a bamboo tube. He peered inside it and, as everyone watched breathlessly, extracted a parchment scroll. When unrolled, it proved to be a faded, yellow map labeled with Cantonese characters.

"A treasure map!" Jim Foy exclaimed. "It tells where there are rich mines of bluish amber!"

A hasty conference followed. Both Tony and Biff felt that they should inform the Hardys and Chet at once. The girls agreed, but asked Jim to remain with them and help guard the treasure map.

lola tucked the scroll into her swimming bag. "Let's radio the Coast Guard to come over here," she said. "I'll feel much safer."

"Okay! Let's go!" Tony urged Biff.

The two set off across the island, scrambled up the cliff, and made their way into the cave. In spite of the wonders revealed by their flashlights, both were too intent on finding their chums to appreciate the cavern's beauty.

Presently they came to the point where the pa.s.sage branched. While trying to decide which path to follow, they heard angry voices coming from the right fork.

"Sounds like trouble ahead," Biff whispered. "Come on!"

178 The boys hurried through the downgrade pa.s.sage, which seemed endless.

Suddenly Tony grabbed Biff's arm. "Hold it!" he hissed. "Do you hear what I hear?"

Biff nodded grimly. Both recognized Chin Gok's voice. Switching off their flashlights, the two crept forward stealthily. Their jaws tightened in horror at the lamplit scene that met their eyes in the huge, subterranean chamber just ahead!

Frank, Joe, and Chet were propped against the wall, their arms and legs bound with ropes. Chin Gok, Dr. Montrose, and the two Coast Guard impostors were standing a short distance away.

"As Butler has just informed you," Chin Gok was saying with evil relish, "all three of you will be tossed into this pool as soon as Dr. Montrose and I put these securities and jewels in our pockets."

Biff and Tony clenched their fists. They must do something! There was no time to go for help. Conferring in tense whispers, they settled on a plan of action.

"It's a long shot," Tony muttered, "but it may work. We'll have to chance it." He took out his jackknife and switched open the blade to cut the prisoners' bonds.

"Okay-now.'"

Like sprinters taking off at a track meet, the two boys burst into the open! Dr. Montrose and 179 Chin Gok, who had not yet picked up the loot, were standing by the green pool. Biff and Tony let out wild war whoops and charged!

Before the startled men knew what was happening, Biff's sudden a.s.sault pushed Chin Gok headfirst into the pool! Tony's hard jab toppled Dr. Montrose after him.

Burns and Butler let out roars of rage. Biff, who was rangy and powerful, sent Burns sprawling and started to tackle the other.

Meanwhile, Tony had begun to slash the ropes that held the Hardys and Chet. Frank surged into action the instant he was free.

Just in time! His first punch made Butler's knees buckle as he was about to land a finishing blow on Biff. But the fight was far from over! Burns was up and now all four tangled in a fierce slugging match. Then Joe waded in and the tide of battle began to turn.

"Quick!" Chet gasped as Tony sawed frantically at his ropes. He had just spotted Chin Gok crawling out of the pool. The enraged Chinese was dripping from head to foot with greenish slime.

A knife flashed in his right hand just as the last strands of Chet's rope parted. The chunky boy moved with unexpected rapidity. Head down, he rammed into the huge Chinese, b.u.t.ting him in the solar plexus. With a gurgle, Chin Gok collapsed in a heap, moaning. Chet took his knife away and threw it into the pool.

180 By now Butler and Burns were reeling and giving ground swiftly. Minutes later they went down, begging for quarter.

"Where's Dr. Montrose?" Frank asked suddenly. "Still in the pool?"

"There he goes!" Joe cried, seeing a slimy green figure just disappearing from the cavern. "Tony! Biff! Chet! Take care of these prisoners!" he requested. "Come on, Frank!

We'll get the Chameleon!"

The Hardys* chums began tying their captives with the ropes which had bound their friends a few minutes earlier. After gathering up the loot, they marched the men out of the cave and down the cliff. Dave Roberts could take charge of them until the Coast Guard sent over officers to look after the prisoners.

Meanwhile, Frank and Joe had raced after the Chameleon. Upon reaching the fork in the tunnel, the young sleuths noticed that the path they had not explored had wet footprints in it.

"That phony doctor went this way!" Joe exclaimed, and they sped through the zigzag opening.

The tunnel was fairly short and rose sharply to the top of the cliff. The exit was so narrow, Frank and Joe had to squeeze through it. Once outside they looked around for Dr.

Montrose. They spotted him jumping from rock to rock down the far side of the cliff.

181 "I see a boat down there!" Frank cried out. "He'll escape in it!"

The Hardys descended the treacherous hillside as fast as they dared but felt that the chase was hopeless. But as Montrose reached the foot of the cliff, the brothers suddenly spied Clams Dagget on the sh.o.r.e.

"Clams!" Frank shouted. "Grab that man! He's a thief!"

The beachcomber-pilot looked up. Recognizing the Hardys, he did not hesitate. Before the fleeing Chameleon knew what was happening, he had been tripped and thrown face down to the sand. By the time Frank and Joe reached him, Clams was seated astride the doctor's shoulders, thwarting the man's efforts to rise. When Mont-rose saw the Hardys, he ceased to struggle and the beachcomber let him get up.

"Now s'pose you fellows tell me what this is all about," Clams demanded.

The boys gave him an account of everything they knew, including the prime clue of the cuff links.

Clams frowned and said, "If we search this jerk, mebbe we can find out more."

Montrose objected, but Frank and Joe held him as the beachcomber began going through the man's pockets. As he looked over the contents of the doctor's wallet, Clams exclaimed: "Quite a bunch o' dough. Hm. A hundred182 dollar bill! By crickey, if there ain't two of "em!"

"Let me see them!" Joe cried out. As soon as they were removed from the wallet he said excitedly, "Frank, these bills belong to you and me! I remember the letters and numbers. Federal reserve notes from the eighth and the fifth districts. The first starts with HIS and ends with F. That's yours. And the other, starting E1015 and ending with A, is my bill!"

The Chameleon's face went white. "You kids are smart," he growled, "but dumb sometimes. I saw you put the money in the envelope and lay it on the mantel while I was casing your house preparatory to opening the safe, so I came in and took it."

"That was was dumb of me," Joe agreed. "Well, get marching. We're going to hand you over dumb of me," Joe agreed. "Well, get marching. We're going to hand you over to the Coast Guard."

As the group of four neared the bathing beach, they could see a Coast Guard cutter docking next to the Hai Hau. Hai Hau. Officers jumped from the craft and hurried toward the boys and Officers jumped from the craft and hurried toward the boys and their prisoners. They got further confessions from the men, including the fact that Butler and Burns were the ones who had signaled to Montrose on sh.o.r.e to tell him and Chin Gok when it was safe for them to visit the island cave.

"We tried to scare you guys away that night you came snoopin' around in your boat,"

Butler told the Hardys. "We hired two men to do it."

183 The brothers learned, too, that Burns had acted as Montrose's "stockbroker" friend.

Clams had been quiet up to this point. Now he burst out, "If I'd knowed you two was such low-downs, I'd never 'a' sold you one mouthful o' clams all those times you come pesterin'

me for 'em. And you never did tell me what that job was you wanted me to do. Guess it was somethin' crooked and you found out I'm an honest guy!"

With the Coast Guard in charge of the prisoners and the loot, the Hardys and their pals said good-by to Clams and headed for the Hai Hau. Hai Hau. Biff now revealed the news about the Biff now revealed the news about the finding of the treasure map.

"Wow-ee" Joe cried out and hugged Tony exuberantly.

Frank followed, grinning from ear to ear. "Super!" he exclaimed. "Say, look who's coming!"

At this moment Ti-Ming, evidently waiting for the boys, walked forward to add his congratulations on the capture of the two slick thieves and their pals. He said he had come to the island in a private launch to tell the boys that Chief Collig and his men had caught the other Chinese who had escaped from jail with Chin Gok.

Upon hearing of the finding of the scroll, he remarked, "Very fine work! The whole gang in custody, and the mystery of the Chinese junk solved! I came prepared to search and help.

Instead, all I can do is offer you a reward."

"Reward?" the boys chorused.

Ti-Ming smiled. "The rightful owner of the Hai Hau Hai Hau instructed me to tell the finder of the instructed me to tell the finder of the clue to the fortune that he would receive a ten per cent interest in it."

"Guess you're elected, Tony," said Frank.

"Hope you make a million," Joe added.

Tony Prito reddened, then said, "Anything that comes to Bayport from those mines of blue amber will be shared, and shared in equal amounts, among the six of us. We all bought the Hai Hau Hai Hau together, didn't we?" together, didn't we?"

Ti-Ming beamed in pleasure. "And you solved the mystery together. Now I must leave, but first I apologize for the telegram about the curse to keep you from selling the Hai Hau." Hai Hau."

As they waved good-by to George Ti-Ming, Frank and Joe wondered what new mystery would rise up to challenge them. They had no way of knowing that very soon a most unusual case, THE MYSTERY OF THE DESERT GIANT, would test their sleuthing abilities to the limit.

Frank went aboard the Hai Hau Hai Hau and rang the junk's melodic bell, calling the picnickers and rang the junk's melodic bell, calling the picnickers aboard.

"It's a little early," Frank confessed to his pals, "but I want to be at the airport when Mother and Dad arrive."

"Yes," said Joe. "And what a home-coming they're going to get!"

THE END.