During the days that followed, the boys saw little of Captain Hollinger. He was largely occupied with getting everything running smoothly aboard ship, during his watches on deck, and except at mealtime he kept to his stateroom at work over maps and papers.

Mart's work was extremely nominal, although necessary. He had few messages to send out and invariably directed that answers be sent at a given time of day, so that he had little more than four hours of work each morning. Bob usually stuck close to the wireless house at this time, and in fact the boys made it a sort of headquarters during the day. It stood back of the chart house on the lower bridge, and the second mate or old Jerry Smith would spend many a "watch below" with them. Swanson, however, kept surlily to himself.

"Liverpool" Peters, the second mate, was a pleasant young Britisher who had been at sea practically all his life, while old Jerry was full of odd ways and tales which delighted both boys, though it was seldom that he would open up to them. He seemed to take a great fancy to Mart, and often when the boys were alone he would wander up, fill his cutty pipe, and settle down for a chat.

The crew was a strange lot. Of the nine men, five were brown-skinned Kanakas, but the other four were white, and seemed to be all old men, though they moved about spryly enough. Dailey was wrinkled and leathery, Birch had only one very black and sparkling eye, Yorke's mouth was twisted into a perpetual smile, and Borden was a quiet little man like old Jerry, gray-haired and respectful.

"They're a queer lookin' bunch," observed Bob one morning, as they left the wireless house and went forward to the bridge, watching the men sluicing down the decks forward.

"You bet," nodded Mart, laughing with sheer enjoyment of the blue sky and bluer ocean. "Where'd you pick 'em up, Jerry?"

Both boys turned to the quartermaster, who was at the wheel in the little house behind them. He smiled, as watches were changed and Dailey came up to relieve him.

"Where'd I find them, Mart? Oh, I just ran across 'em. Dailey, here, used to be on a ship wi' me, once." He looked around, and the leathery seaman grinned slightly.

"Who'll do the diving?" asked Bob, as they walked back to the wireless house and flung themselves into deck chairs, while old Jerry filled his pipe.

"Two o' the Kanakas, lad. They're main good at that."

"Are you goin' hunting with us?" shot out Mart. "Tiger hunting?"

"That depends, lad, that depends," and Jerry wagged his head solemnly. "I never killed a tiger yet. I've killed whales, though, aye, and tiger sharks! Think of the mystery of the sea, lads—wave after wave, with the fish down below and us up here above! Fish tell no tales, lads, fish tell no tales. There's strange things out where we be bound for."

"What?" asked Bob eagerly. "Sharks?"

The quartermaster nodded. For a moment he seemed to hesitate, then turned to Mart and laid a hand on the boy's knee.

"Lads, did you ever hear tell o' the Pirate Shark?"

Mart thrilled at the name, and the tone of the old man's voice gave him a creepy feeling, as it often did.

"No!" he exclaimed delightedly, scenting a yarn. "What about him?"

"Well, I've heard as he's livin' in the very place we're going to—that Kuala Besut, off Tringanu."

"Huh?" grunted Bob, sitting up quickly. "And us going to dive? Not much!"

Jerry laughed softly, gazing out at the sparkling waters.

"The Kanakas ain't afraid, lad. Only they don't know—they don't know. You see, this here Pirate Shark is pretty famous down through the Chiny Sea. But old Jerry Smith, he's the only one that knows. He's the only white man, lads. The Chinks know, and the Malays know, but they wouldn't go near the place. The mystery o' the sea, lads—wave after wave! The gold down below, and us up above—and fish tell no tales, lads—"

He fell silent, still gazing at the horizon. Mart glanced at Bob, and caught a significant wink as Holly tapped his forehead. Mart frowned.

"What do you mean?" he asked sharply. "Is there a shark by that name? What kind o' stuff are you handing us, Jerry?"

The old man turned and looked square at him, and his gentle face seemed suddenly changed into a swift vehemence that was amazing. But it vanished instantly, and he was himself again—as if he had put on a mask, thought Mart quickly.

"The Pirate Shark," answered old Jerry slowly. "Yes, I'll tell you about it, lads. There ain't many as knows where the Pirate Shark is, but old Jerry Smith, he knows. He's a big shark, he is—mighty big, an' a man-killer. He come up first at Thursday Island, years ago, an' caught half a dozen Jap pearlers. Then he showed up in the Flores Sea, an' for a year the fishers didn't dare visit the pearlin' beds. After that he went over to the Sulu Islands, down to Java, back to the Chiny Sea—always killin' men, natives or white. Then he vanished for a while—mystery o' the sea, lads, wave after wave—"

Again the old man paused, dreaminess on his gentle face. The boys were leaning forward eagerly, and Bob brought him back abruptly to the subject.

"But what about this place we're goin' to? Is he there now?"

Once more that peculiar look flitted across the wrinkled face—a look of swift suspicion, that vanished as quickly as it came. Jerry smiled softly.

"Why, yes! See here, lads, you promise you'll say nothing? I likes you fine, but I don't want news leakin' out. I'm an old man—fish tell no tales, lads—"

"Of course," agreed Mart instantly. "We'll keep quiet, Jerry." Bob nodded.

"Well, this is a yarn as a Chink told me, lads. But it's true, gospel true! A long time ago there was only Portugees an' Dutch in the Chiny sea, an' they carried on somethin' awful, fightin' an' robbin'. Once there was a big battle—"

"Yes!" volunteered Bob eagerly. "I was readin' about it last night—that time back about 1600 when the Dutch fought a Spanish armada for a week an' licked 'em!"

"It was a big battle," went on old Jerry. "One o' the ships drifted up to the coast of Tringanu an' sunk. Some o' the men got away, but she's there still—right where we're goin', lads, in Kuala Besut Bay. She's got treasure aboard, gold an' pearls an' such, an' the Pirate Shark's guarding her."

"Oh, rats!" laughed Mart, to whose practical mind treasure stories were all absurd. "If there'd been any treasure there it'd be gone long ago."

"So?" Jerry looked at him, and Mart felt suddenly afraid, so strange was the look in the bleared old eyes. "So? This Chink had been there wi' some Chink divers, after pearls, lads. O' course, folks know the wreck is down there, eight fathom down, lads. The Dutch has been there, the Japs, the Chinks—but they didn't get the gold, lads! 'Cause why? The Pirate Shark is there, keepin' watch. The divers went down, but he cut their air lines—he cut their air lines, lads! And they didn't come up. He's got a black fin, a big black back fin, which is one reason why he's called the Pirate Shark.

"But there's another reason, lads. That's because he went from one pearl fishery to another, cuttin' air hose, killin' men, keepin' the pearlers off the grounds. They were scared of him all through the south seas. When the big black fin cut the water, not even a Jap would go down. Fish tell no tales, lads, fish tell no tales! Man after man he ate, Malay an' Chink an' Britisher an' Arab, and now he's got the old galleon an' her gold, and no one knows where it is but the old quartermaster. The fish down below, lads, and us up above—"

"I guess you're mixed up, Jerry," said Bob quickly. "A little while ago you said that lots o' people know the wreck is there, but just now you say no one knows where it is except you. How 'bout that?"

Jerry chuckled, rising slowly to his feet.

"She's inside the lagoon, lad, eight fathom down, an' no one knows but old Jerry Smith where she is now. She used to be under the sand, but the tide and the river dug her out and she drifted, drifted, down with the fish. Fish tell no tales, lads—fish tell no tales! Now she's wedged up among the rocks, eight fathom down, wi' the Pirate Shark's flag over her. Lads, ye won't tell the cap'n or Joe Swanson that old Jerry told ye about the Pirate Shark, will you?"

"Sure not, Jerry," chorused the two together. Jerry nodded and turned.

"Well, I got to get down an' see to gettin' that cable flaked." And he shuffled away, muttering still of "wave after wave—the fish down below and us up above!"

The two boys stared at each other, their eyes sparkling. Incredible, wild and fantastic as the yarn sounded, something about the old quartermaster's manner had impressed them both with the fact that he believed it firmly.

"Do you s'pose it's true, Holly?" asked Mart.

"Blamed if I know," returned Bob slowly, for he seldom gave any direct opinion on a subject. "O' course it isn't true, because if he knew about that place and the gold and the wreck, he'd get after that shark in short order. It's prob'ly a sea yarn."

"I ain't so sure," returned Mart. "It sounds fishy," and Bob grinned. "Well, it does, for a fact. But Jerry believes it himself, that's sure. I tell you what, Holly, if that Pirate Shark's really there, and them Kanakas get to diving, we're goin' to see something! Some idea, though! A big shark cruising around the pearling beds, killing men, and finally taking possession of an old wreck full o' treasure! Why, it reads like—like a Jules Verne story! Say—you remember that dynamite your dad said Jerry wanted put aboard?"

Bob looked up, startled, and gave a nod.

"Well, I bet a cookie Jerry's goin' after that Pirate Shark with it!"

"What!" Bob's blue eyes widened and his face lost its careless expression. "By juniper! Mart, do you s'pose he's after the gold? Let's ask dad—maybe that's what he meant all along by gold mining—"

"Hold on there," cried Mart, hauling back the eager Holly. "We promised we wouldn't say anything to your dad or the mate, remember? Hello, here comes Birch with a message I've got to send, prob'ly."

"I'll ask him," began Bob, then the one-eyed seaman entered and touched his brow.

"Cap'n's compliments, Mr. Judson," he said in his ever-respectful way, "and he wants you to send this here message."

"All right, Birch," and Mart took the note. "Just a moment! Did you ever hear of the Pirate Shark?"

For a moment both boys were frightened by the effect of those words. The old seaman whirled about, his one black eye blazing weirdly and his face contorted. Then he collected himself with a little laugh.

"Beg pardon, sir. That there word 'pirate' allus gets me, 'count of a brush I oncet had with pirates in the Sulu Sea. Why, sir, I've heard summat o' that there fish; they say he's a monster shark with a black fin, that he's a man-eater, an' haunts the pearl fisheries. Beggin' your pardon, sir, but where might you have heard of him?"

"Oh, we just heard some of the men talking," answered Bob carelessly, and Birch touched his forelock again and was gone. For a second time the boys' eyes met.

"Holly, this doesn't look right to me," said Mart finally, his gray eyes hard. "Birch knows more'n he said. That explanation of his don't go down with me, not a bit! I wouldn't wonder if there was such a fish—right where we're going, too!"

"By juniper!" Holly's face was troubled. "Of course, it's likely; such a fish would hang around the pearl beds, 'cause that's where he'd most likely meet up with divers. If he's a man-eater, he'd do that. The story sticks together pretty well, Mart! Of course we've got to remember that sailor yarns generally are stretched."

"Well, you lay low," cautioned Mart, reaching for his key and sending out a crashing spark in call, over and over. Then he leaned back and waited for an answer. "We can't go to your dad with this, and anyway, Bob, there ain't much behind it. Here—I'll tell you! Mebbe that shark is there, and old Jerry got the dynamite to have some fun with on his own hook. If there was any wreck or treasure, he'd have kept his mouth shut."

"That sounds more like it, Mart. Still, he's a talkative old guy, and he likes us a heap, you in particular. There's somethin' queer about it, though. Jerry said that Dailey—the leathery old scoundrel—had sailed with him before; then there was that talk between him and Swanson. And have you noticed anythin' queer about the way those men hang together?"

Mart sent him a quick look, as he adjusted his headpiece.

"Huh? Well, I've noticed that they obey Swanson a heap quicker than they do Peters. Peters got mad yesterday an' knocked that grinnin' Yorke galley-west! But they're old men, Bob."

"That's just it," returned Holly earnestly. "So's Jerry old, and Swanson ain't a spring chicken by any means. They hang together, that's all. And remember, Jerry was the one that signed 'em all on. I'll get dad to mention the Coralie one o' these days."

"Well, you go slow," cautioned Mart again. "Hello—there's a call—" he leaned forward. "TTY—that's the Tenyo Maru. She's just out o' San Francisco, so she can relay a message, I guess. Golly, your dad's keepin' close watch on the stock market!"

He grinned as he sent out the message and Bob watched the blue spark leaping in fascinated silence. After all, this story of the Pirate Shark was a wild fancy, and these were the prosaic days of wireless and steam power; the whole tale was doubtless one of those strange and utterly improbable yarns that some intoxicated sailor cooks up and other sailors improve upon and embellish. At least, that was the opinion of the two boys as they left the wireless house and joined Captain Hollinger, who had just come to take the bridge. Mart wished they had not made Jerry that promise, however.