Wither-spoon home and returned to open Dad's safe. Something frightened him and he ran off in a hurry, leaving the front door open. Then Chet came along."

"Sounds good," Joe remarked. "But if he steals securities whenever he gets a chance, why didn't he take the ones in our safe?"

"He didn't want that particular job to look like 163 a robbery," Frank answered. "All he wanted was Dad's file on the Chameleon."

Joe's eyes opened wide. "Are you trying to tell me you think Montrose is the Chameleon?"

"I am." Frank gave a loud sigh. "And we let him slip right through our fingers. The Chameleon is sure a perfect name for that guy! He managed to fool other doctors in town evidently."

Joe said he thought they should phone their father at once, so as soon as the boys reached home, Frank put in the call. His brother, meanwhile, gave Aunt Gertrude an account of the evening's adventures.

"Dr. Montrose!" she cried out. "And he seemed like such a gentleman! So he's not, eh?

Then he ought to be tarred and feathered when they catch him. The idea of giving people sleeping pills and then robbing them!"

"Take it easy, Aunty," Joe advised. "Remember, we haven't proved a thing yet."

By this time Frank had made the connection to California and in a moment his father came on the phone. Mr. Hardy listened in amazement to the story and his sons' deductions.

Then he said: "One of my secret findings contained in the Chameleon's files was that he had read a great deal about medicine and learned enough to pose as a doctor. But the last place I'd expect to find him practicing would be Bayport! At the time the 164 file on Balarat was taken from my safe, I had just received a good lead that he was out here, and I figured some cohort of his had opened the safe."

Mr. Hardy went on to say that the ex-convict might remain in hiding for some time, now that he knew his latest role as a doctor had been detected. "But keep your eyes open, Frank, and Joe too," the ace sleuth advised. "I will fly home tomorrow with Mother to take up the hunt."

After Frank put the phone down, Aunt Gertrude looked hard at him, then said crisply, "Not one more bit of mystery tonight for either of you boys. You both look as white and tired as if you'd been through an epidemic!"

"An epidemic of clues," Joe quipped, but he and Frank were glad to climb into bed and were asleep in a few minutes.

The following morning was bright and warm and the Hardys looked forward to a full pa.s.senger list for the Hai Hau. Hai Hau. They found Aunt Gertrude busy in the kitchen taking m.u.f.fins They found Aunt Gertrude busy in the kitchen taking m.u.f.fins from the oven.

"Wow! What a breakfast!" said Joe. "Here's a kiss for the cook." He planted one on her cheek.

"Good morning, Aunty," Frank added, putting an arm around her.

The wall phone in the kitchen rang. Joe picked it up and listened a moment, then burst out: "What! Chin Gok and the other two prisoners have escaped, you say, Chief?"

CHAPTER XIX.

Sleuths in Danger.

frank, Joe, and Aunt Gertrude were stunned by Chief Collig's report that the three Chinese prisoners had broken out of jail.

"Somebody helped them," Aunt Gertrude declared firmly.

"He sure did," Joe agreed. "The chief said someone slugged the jailer and opened the cell they were in. The fellow was masked and as slick as they come. n.o.body saw him sneak in."

Frank gazed into s.p.a.ce. "I wonder where the bunch of escapees went. They must be in hiding. Maybe-"

"Maybe what?" Aunt Gertrude asked.

Her nephew merely "smiled and she knew his idea was still in a nebulous state. He would tell her later when it was fully formulated. As the brothers drove down to the Hai Hau Hai Hau to help with the day's run, Frank said: "Joe, I was thinking of that cave on Rocky Isle and those blinking lights. It's just possible Dr. Montrose is hiding out there."

"And perhaps Chin Gok and his pals?" Joe queried.

"Yes. Let's take a look and if we see any of them we'll radio the police."

At the pier Frank and Joe found Chet with his spelunking gear, ready to explore the cave. But when the stout boy heard of the jail break and Frank's supposition that the wanted men might be hiding there, he looked worried.

"I don't know that I'll explore, fellows. You can't move fast in this gear and I sure couldn't run if I had to."

"Well, suit yourself," said Joe.

Several picnickers had already gathered. Among them were Gallic Shaw and lola Morton. The girls had brought a basket of food, a portable record player, and a beach bag containing towels and bathing suits.

"Hey! Look who's here!" Joe cried out.

"Be our guests!" Frank invited. "We'll reserve deluxe seats right here with the crew-no charge!"

The two girls dimpled into pleased smiles but insisted upon paying their own fares.

Laughter and banter continued as the junk cruised out of the harbor. Then lola turned on a new hit record.

167 "Too bad there's not enough room to dance." she sighed. "Let's all sing instead!"

Everyone joined in the chorus, drowning out the crooning voice on the record. Biff sang slightly off key.

"Hey! Those pipes of yours are rusty!" Tony joked and held up an oilcan. "Try some."

Presently the radio connected with the Hardy home signaled and Aunt Gertrude's voice came on. Frank put it down to low volume so only the young sleuths and their friends could hear her.

"A phone message just came from Ardvor College," she said. "Dr. Montrose was never a student there and the president is very upset by his claims. I've notified Chief Collig.

Anything else you want me to do?"

"Not now. And thanks a million, Aunty," said Frank. "Over and out." Turning to his friends he added, "If we need extra proof about that phony, we have it now!"

As soon as the junk tied up at the wharf, its pa.s.sengers trooped ash.o.r.e and headed for the beach. Frank told the girls that he and Joe were going to the cave, but did not give the reason. Chet decided to don his spelunking helmet and accompany them. Tony, Biff, and Jim would go back to Bay-port for the second load of pa.s.sengers.

The Hardys and their stout chum tramped across the island. Reaching the park guard's house, they stopped to ask Dave Roberts if he had 108 seen any blinking lights or cliff climbers on the northern end of Rocky Isle.

"No," he replied, and the boys went on.

The trio skirted the rocks along the sh.o.r.e and half an hour later started up the cliffside.

Twenty minutes of scaling brought them to the mouth of the cave.

"If those jailbirds climbed up these rocks, they sure made it hard for themselves," said Chet, puffing. "I don't believe they're here."

"Just the same, we'd better talk in whispers," Frank recommended.

The three boys pressed forward into the gloomy cave. They had barely entered when several rocks near the opening went clattering down the hillside. The vibration loosened a ma.s.sive chunk of limestone hanging from the cave ceiling.

It plunged straight toward Joe's head!

"Look out!" Chet yelled.

Joe dived clear in the nick of time, aided by a lightning grab from Frank. The huge chunk of limestone smashed on the spot where Joe had just been standing! All three boys were showered with whitish dust and rock fragments.

"Whew! It-it was almost curtains that time!" Joe's voice came in a weak whisper. He lay sprawled full length on the cave floor.

Frank helped him to his feet. "Are you all right?"

The ma.s.sive chunk of limestone plunged toward Joe 170 "I guess so-thanks to you two!" Joe gulped. "Boy, if you hadn't yelled, Chet-"

"Now you know why I wear this miner's hat!" Chet replied.

Suddenly Frank said, "We certainly made a noisy entrance. If anyone's hiding, we probably alerted him."

Joe nodded. "That gives him the advantage. We'd better proceed with the utmost caution and not get trapped."

As they advanced, the boys beamed their flashlights in every direction. Presently they found themselves in an enormous room.

Pearly terraces rimmed the walls, extending far back into the cliff. Glittering calcite icicles hung from the ceiling.

"This is a living living cave," Chet whispered. "That means there's always water seepage cave," Chet whispered. "That means there's always water seepage going on. It builds these queer, shiny formations. When the seepage dries up, the rock gets dull and crumbly, and the cave becomes dead."

Chet now lighted his helmet lamp and the boys proceeded deeper into the cave. The floor became more rugged, forcing them to pick their way along cautiously.

The path they were taking gradually sloped upward. Another branch of the cavern, opening on their right, seemed to lead down toward the base of the cliff. The boys hesitated, uncertain which way to go.

171 "In the daytime those men would be more likely to hide down below the top of the cliff,"

Frank suggested.

The others nodded, and the boys pushed on into the right-hand cavern. Here, the "icicles" increased in size to huge spearlike stalact.i.tes. Here and there similar-shaped stalagmites reared upward from the floor. Sometimes the twin formations joined in glistening pillars or columns.

"Just thinkl This was all done by water dripping slowly for hundreds of years," Chet marveled.

"What a spectaclel" Frank whispered. "This place ought to be opened up to the public."

Most eye-stopping of all was a frozen cascade that had formed over a ledge, like a miniature Niagara of stone. It glistened with a fairylike brilliance in the glow of the flashlights and lamp.

"Chet, this is super. I'll never make fun of your spelunking again 1" Joe declared in a low, awed voice.

To add to the beauty, some of the deposits were tinted orange, red, and brown. Chet explained that this was due to iron oxide and other minerals in the dripping water.

As the boys continued downward into the cliff, their body heat caused wispy fog to form in the cool, damp air. Suddenly Frank halted and listened.

"I thought I heard a voice."

172 The boys tiptoed ahead and presently the twisting pa.s.sageway opened into a larger cavern. In the middle lay a huge pool, its surface covered with a thick sc.u.m of green algae and slime. A slight movement of the water indicated that the pool was being fed from some underground source. The ocean?

"Lookl" Frank whispered excitedly, pointing across the pool.

Joe and Chet swung their lights toward the spot. Revealed was a typewriter with the name Zeus on it. No doubt the stolen one! Next to it was a low table on which stood stacks of what looked like bonds or other financial certificates. On top of these was a foot-square bamboo box with Oriental characters on it.

"We've found it!" Joe gasped. "This is is the thieves' and smugglers' hi-" the thieves' and smugglers' hi-"

His words ended in a groan as a hard object crashed against his skull 1 Before Frank and Chet could turn around, they too were struck down from behind. All three sank into blackness.

When the Hardys and Chet regained consciousness, it was like waking to a flickering nightmare. The boys could feel ropes biting into their wrists and ankles. They were bound and propped against one wall of the cavern, now lighted by carbide lamps. Frank's watch revealed that three hours had gone by since the boys had left the dock.

Frank was first to collect his wits fully. Then 173 Joe and Chet slowly brought their eyes to a focus on four figures leering down at them; Dr. Mont-rose, Chin Gok, and two rough-looking men in seamen's dungarees.

"The phony coastguardmen!" Frank said grimly.

"Yes," one of them replied, "but you'll never live to report where we are." He laughed scornfully.

Frank took a deep breath. "In that case, you won't mind clearing up the mystery first," he said, sparring for time. "Dr. Montrose, we know you're Balarat, the Chameleon. You're wanted on various charges, including the display of a fake diploma. But what is your connection with Chin Gok?"

"I'll answer that," the Chinese spoke up and gave a harsh, leering laugh. "Balarat and I are new in our acquaintance but already very good friends. He helped us slip out of jail. The doctor and I thank the Hardy boys for our first meeting. It was at your house."

"Our house!" Frank and Joe gasped.

Chin Gok grew voluble. "It was quite by accident," he confessed. "I entered your home one morning to search for any data you might have picked up regarding the Hai Hau. Hai Hau.

Incidentally, it was my esteemed self who spoke that warning over the radio. That was between the doctor's first and second visits that day. I followed him up174 stairs and watched him open your father's safe." The Chinese smiled. "I might have blackmailed him, but when Montrose saw the unusual cuff links I was wearing, he recognized them as part of a smuggled shipment of amber. As payment for his silence, I gave them to him. Then we decided to join forces and outwit the Hardy family!"

"Chin Gok," Joe said, "did you steal all six junks in Hong Kong and secrete smuggled goods aboard, part of it bluish amber tigers? And did you have the junks shipped to foreign ports where you picked up the loot and sold it?"

"True," Chin Gok replied. "I have sold everything, except the valuable bluish ambers in the bamboo box, with the help of Dr. Montrose." A self-satisfied smile played over the smuggler's face. "Friends took care of five junks. I came to New York because I was particularly interested in the boat I repainted and put the mandarin figurehead on, and gave the name Hai Hau." Hai Hau."

Chin Gok spoke proudly. After a pause he went on, "I had some of my men ruin the junk's engine and later attack you boys in Chinatown. After that, they put a hole in the junk to discourage you from keeping the Hai Hau." Hai Hau."

"Did they also slug the dock watchman and make a search aboard?" Joe asked.

Chin Gok nodded. "They almost got the Hai Hau Hai Hau away from you one night out on the away from you one night out on the Sh.o.r.e 175 Road. And they did scare you with a warning note."

Frank looked hard at the man. "You're the one who pretended to be stooped like Clams Daggett when we saw you leave Montrose's house."

"Yes."

Frank turned to Dr. Montrose. "And you lost one cuff link when you met Chin Gok at the cave and dropped the other in your bas.e.m.e.nt."