sign, as Jack had observed, that he was disturbed.

“I’ll make all snug, sir,” the boy heard the captain say, as he turned away, “and then we will be prepared for whatever happens.”

“Very well, Sparhawk,” answered Mr. Jukes, in a somewhat louder voice than he had used hitherto, “and be sure to see to it that the deck load of coal is secured safely. They tell me the bunkers are running low.”

As has been stated, the Sea Gypsy’s decks were piled high fore and aft with coal, kept in place by wooden bulkheads, which did not add to the appearance of the ship and encumbered progress from bow to stern. Only amidships, where the cabins were situated, was the deck clear. As the captain ascended the bridge he turned and gave an order to a petty officer and presently the crew could be seen at work lashing big tarpaulins down over the coal which was so important to keep the Sea Gypsy moving on her mysterious mission.

The news that the coal supply was running low in the bunkers was a surprise to Jack. He made for Billy Raynor’s cabin where the young chief engineer of the yacht was writing up his “log.”

“Yes, it’s right,” he rejoined to Jack’s question, “the loss of that deck load would be a serious matter. We’re a good many hundred miles from land and will have to tap the supply before long.”

“Billy, what on earth do you suppose is the object of this voyage?” demanded Jack abruptly.

“Blessed if I know, but I’m well satisfied with my promotion and job,” declared Raynor. “Cruising these wonderful seas in a yacht that’s a beauty, even if her decks are all littered up like a cattle boat’s, just about suits me.”

“That’s all right, you’ve got something to do,” complained Jack. “But look at my case. I have to polish up my instruments every day to keep them from getting rusty.”

“Serves you right for not stopping ashore and enjoying yourself,” chuckled Raynor teasingly. “Since you sold that ‘Universal Detector’ of yours to the government you could surely afford to.”

“Just as if I could kick my heels on shore doing nothing,” was Jack’s indignant reply, “but it does seem as if it’s about time we knew something of what this voyage is for.”

“Maybe it’s just a pleasure cruise to allow Mr. Jukes to get away from his business troubles,” hazarded Raynor.

Jack shook his head in decided negative.

“There’s more in it than that,” he declared positively. “Mr. Jukes is first of all a man of business. He wouldn’t come skylarking across the Pacific for three weeks if he was just out for a cruise. He’d go where he could keep in touch with the market and Wall Street.”

“That’s so,” Raynor was compelled to agree. “Well, I suppose when he gets ready to spill some information he’ll do it. In the meantime my job just suits me. But what made you ask about the deck coal?”

“Because Captain Sparhawk says we’re in for a bad blow, maybe a hurricane.”

Raynor’s usually cheerful face became suddenly serious.

“When did he say that?” he asked.

“Just now. They’re putting tarpaulins over it now. If we dropped it, we’d be in a bad fix, eh, Billy?”

“We’d have about coal enough left for two or three days,” rejoined Raynor.

“And after that——?”

“It would be a case of ‘merrily we drift along.’”

The door gave a sudden sharp slam. A puff of wind, sweeping suddenly over the hitherto breathless sea, had banged it shut.

Jack jumped up and swung it quickly open again.

“Here she comes,” he cried excitedly.

At the same instant the Sea Gypsy gave a sidelong lurch that sent both lads helter-skelter across