conversation. He bowed again, waved his hand as if to indicate that the ship was theirs, and turned and walked to the bridge.

The boys looked around them. There was nothing to be seen but an expanse of water. There was not a sign of land or a vessel. The storm of the night before had subsided, except that the waves were still running high under a brightly shining sun. Harry put his hand to his eyes to shade them, and scanned the horizon in every direction, but there was not even a speck to be seen.

"The captain was right when he said there was not much danger of losing our company," he said, as he finished his observation.

"Unless we jump over and swim for it."

"What would we swim for?"

"I am very well satisfied to keep the planks under my feet and wait for something to turn up."

"Me, too," piped the Midget. "Let's make a round of the ship."

The steamer was comparatively small. In the darkness of the night and the storm, and viewed from the little sloop, she had looked like an ocean liner as she suddenly came upon them. Everything about her was spick and span. The decks were as clean as holy stone and water could make them, and all the brasswork shone brightly in the sun. The decks seemed strangely deserted. Suarez, the mate, paced the bridge stolidly. On the forward deck two men were on lookout. In the pilot-house a sailor stood at the wheel, while behind him stood a man whose eyes roamed constantly from the compass to the horizon.

The boys walked to the gunwale and looked over at the broad expanse of sea. For some time no one spoke. Each was thinking of the worry and anxiety that those at home were suffering.

"Say, Hal," said Bert, finally, "what do you make out of this craft? Of course it is out of the question to think of a pirate in these days, but there is certainly some mystery about this steamer and her captain."

"Did you notice he said that if he could do so with safety he would put us ashore? What does that word 'safety' mean? There is no danger from the elements, he admits. What other danger threatens him if he goes ashore? There is some mystery here and as we have become a part of it it is up to us to find out what it is."

"Yes, but how?"

"By keeping our eyes and ears open is all I can suggest now."

"Let's go forward and take a look around."

The boys strolled along the deck that narrowed into a passage about three feet wide as they reached the forward house, which apparently contained the petty officers' rooms. In the centre was the door that opened into the engine-room. Only the upper works of the big engines were visible. The boys stopped. A man, evidently the engineer, or one of his assistants, sat on a leather-covered seat facing the levers and indicators. He looked up for a moment from the paper he was reading, and nodded to the boys with a smile, and then returned to his reading without a word.

"Fine morning, sir, after the storm," said Bert.

The man nodded again without raising his eyes from his paper.

"Cheery lot of conversationalists," said Bert, in disgust, as they moved on.

At the forward end of the house was the galley. As they reached this a black, woolly head popped out of the open half-door. The negro grinned widely and quickly drew back his head.

"Good morning, Sambo," said the persistent Bert.

The negro bobbed his head, and grinned still more broadly, but did not speak a word.

"All lost their tongues," said Bert.

Just forward of the deck house a small hatch stood open. It led to a narrow iron ladder that ran almost perpendicularly down into the dark depths below. The boys peered into the blackness without being able to distinguish anything.

"I am going down," said Harry, after a moment's pause.

He stepped over the edge and placing his foot on the first rung of the ladder, began to descend with great caution. The others watched him anxiously until he disappeared in the darkness. They waited at the hatch for a long time before he reappeared. When he did he climbed out with a serious face and drew his companions away to the other side of the steamer's deck.

His expression indicated that he had discovered something of more than ordinary interest.

"What is it?" whispered Bert, when they were out of range of the galley and engine-room.

Harry leaned toward his companions impressively as he answered in an awed tone:

"Say, fellows, she's a regular warship down below."

CHAPTER IV

A Lesson in Patriotism

The boys huddled together at an obscure part of the deck and Harry described to them what he had seen below decks.

"There are two eight pounders and two rapid fire guns with their noses poked against port holes that can be opened at a moment's notice. And besides these, there is an arsenal of small arms like rifles, pistols, swords, and cutlasses. Everything seems to be in apple pie order and all ready for use. If we were living in the days of the old pirate ships, I should say that we were likely to fly the black flag at any moment."

"What do you make of it, Hal?" asked Bert.

"I tell you I cannot make anything of it. It is beyond me. The only thing we can do is to keep our weather eyes open and watch for developments. It is certainly a ship of mystery and the captain does not apparently propose to enlighten us as to her character. But he seems to be an honest man, and I think we are perfectly safe in leaving all to him, and I believe that sometime we shall know what we are up against. In the meantime, however, as I warned him, I shall make every effort to get off the ship, or to notify some passing craft that we are on board safe and sound, so that word may be carried to those on shore. They must believe that we are drowned by this time, particularly if they have picked up the wreck of the yacht."

"Let's go aft and take a look over the cabin while the captain is asleep. All's fair in love and war, you know, and we are certainly entitled to find out all we can about our surroundings, particularly in view of Hal's investigations below."

The boys strolled leisurely aft, taking care not to arouse the suspicions of any one about the decks. They entered the cabin. All was still. The sun shone brightly through the port holes and lay in a wide beam on the big map that the captain had been studying when the boys turned out of bed.

"Let's have a look at this," said Bert, quickly approaching the table as he spoke. "It may tell us something of our destination."

The boys gathered eagerly around.

The map was a hydrographic chart of the Caribbean Sea. Cuba and Porto Rico appeared on a large scale. The boys studied it in silence and finally Mason shook his head in despair.

"That does not tell much," he said. "We may be going to Cuba or Porto Rico, but if we are, why all this secrecy and those firearms?"

"They may fit in together more closely than you think," said Harry, who had been studying the map thoughtfully.

"What do you mean?" asked Bert.

"I do not mean anything yet. Let us wait. Speculation and guessing will not solve this mystery."

"Look here," said the Midget, who had been browsing around the cabin. He had lifted one of the cushions from a settee and disclosed beneath a locker which contained a number of flags of different colors and shapes.

"What are those?" asked the boys in chorus.

"They are signal flags. Now let's find the code and then we can signal some passing ship."