The four sailors who were with Clif fully realized the task which was before them.

It was then about dusk, and the night was coming on rapidly. Two of the men were stationed as lookouts, and the other two took the wheel.

Clif set to work to try to calculate as best he could how far and in what direction he was from Key West; he wished to take no chances of running ashore or getting lost.

Those, and the possibility of collision, seemed the only dangers that had to be guarded against; the possibility of meeting a Spanish vessel was not considered, for the chance seemed very remote.

The two lookouts were both stationed in the bow. That fact and the other just mentioned sufficed to account for the fact that the real danger that threatened the crew of the merchantman was not thought of or guarded against in the least.

For Clif had no way of knowing that any trouble was to come from behind him; but coming it was, and in a hurry.

Within the shelter of a narrow inlet just to one side of the batteries that had made so much trouble for the Uncas had lain hidden and unsuspected an object that was destined to play an important part in the rest of the present story.

It was a Spanish gunboat, of much the same kind as the Uncas, only smaller. Hidden by the land, her officers had eagerly watched the struggle we have just seen.

The Spanish vessel had not ventured out to take part, for one important reason; she had not steam up. But she would probably not have done so anyhow, for the Uncas was the stronger of the two.

And so venturing out would have been little better than suicide. The Spanish captain had a plan that put that one far in the shade.

The Uncas was still visible down the shore, and the merchantman had hardly gotten well started out to sea before great volumes of black smoke began to pour from the furnaces of the Spaniard.

Her men worked like fiends; sailors pitched in to help the firemen handle coal, while the shores of the dark little inlet flared brightly with the gleam of the furnaces.

Meanwhile the officers with their glasses were feverishly watching the distant steamer, now hull down to the north, and almost invisible in the darkness.

It was about half an hour later, perhaps even less, that that Spanish gunboat weighed her anchor and stole silently out to the open sea.

She breasted the fierce waves at the entrance to the inlet boldly. A minute later she was plowing her way through the storming sea. It was dark then and she could see nothing; but her captain had the course to a hair's breadth.

He knew which way his prey was gone, and he knew to what port she was going. He knew, too, that she would not dare go near the harbor of Key West until daylight. And so if by any chance he missed her in the darkness he would still have another opportunity.

And those on the shore who saw the vessel glide away chuckled gleefully to themselves. It was something to look forward to, a chance to revenge themselves upon the impudent Yankees who had dared to elude the fire from their guns.

Meanwhile the Yankees, totally unsuspicious of this last move, were buffeting their way bravely ahead.

The lookouts clinging to the railing in the bow were peering anxiously ahead in the darkness, and the sailors in the pilot house were wrestling with the wheel; it was quite a task to keep that vessel headed straight, for she was going into the very teeth of the gale.

And as for Clif, he was watchfulness personified. When he was not eyeing the compass carefully he was hurrying about the vessel, now down in the fire-rooms, making sure that those Spaniards were doing as they were ordered, and again looking the prisoners over to make sure that the sly rascals had not wriggled themselves free.

"It would be a fine thing to do," he thought to himself, "if they managed to recapture the ship."

There was something quite prophetic in that thought.

It is hard to keep awake all night, but a man can do it if he has to even though he has been working like a Trojan all day.

Clif kept moving to work off the sleepiness whenever he felt it coming on.

"I'll have time enough to sleep by and by," he muttered.

He was thinking, grimly enough, of how he would be stalled in the town of Key West with his prize, waiting for a chance to get out to the fleet again.

The vessel did not attempt to make more than half speed during the trip, and that, against the storm, was very little.

But there was no need to hurry thought every one.

And so for some two hours the vessel crept on, wearily as it seemed and monotonously. The only thing to vary matters was when some extra high wave would fling itself over the bow in a shower of spray.

But that was not a welcome incident, for it made it harder for the weary sailors to keep the course straight.

The cadet paced up and down the deck; he had been doing that for perhaps the last half hour, stopping only to say a cheery word to the lookouts and once to prop up Ignacio, who was being rolled unceremoniously about the deck.

The cunning Spaniard looked so bedraggled and miserable that Clif would have felt sorry for him if he had not known what a villain he was.

"He'd stab me again if he got a chance," he mused.

For Clif had saved that fellow's life once; but it had not made the least difference in his vindictive hatred.

"I'm afraid," Clif muttered, "that Ignacio will have to suffer this time."

The Spaniard must have heard him, for he muttered an oath under his breath.

"It would be wiser if it was a prayer," said the cadet. "Ignacio, you are near the end of your rope, and you may as well prepare for your fate."

The man fairly trembled all over with rage as he glared at his enemy; such rage as his was Clif was not used to, and he watched the man with a feeling of horror.

"I don't like Spaniards!" was the abrupt exclamation, with which he turned away.

And Ignacio gritted his teeth and simply glared at him, following back and forth his every move, as a cat might.

"I may have a chance yet," he hissed, under his breath. "Carramba, if I only had him by the throat!"

But Clif paid no more attention to the Spaniard. He had other things to attend to, things to keep him busy.

It was not very long before that was especially true. For some interesting events began to happen then.

They began so suddenly that there is almost no way to introduce them. The first signs of the storm was when it broke.

In the blackness of the night nothing could be seen, and the vessel was struggling along absolutely without suspicion. And Clif, as we have said, was walking up and down engrossed in his own thoughts, almost forgetting that he was out in the open sea where a Spanish warship might chance to be lurking.

And so it was literally and actually a thunderbolt from a clear sky.

The blackness of the waters was suddenly broken by a sharp flash of light, perhaps two hundred yards off to starboard.

And an instant later came the loud report of a gun.

The consternation of the Americans it would be hard to imagine. They were simply aghast, and Clif stood fairly rooted to the deck.

His mind was in a tumult, but he strove to think what that startling interruption could mean.

"They must have fired at us!" he gasped.

And if there was any doubt of that an instant later came a second flash.

To a merchantship in war time such a signal is peremptory. It means slow up or else take the consequences.

There were two possibilities that presented themselves to the commander of this particular merchantship. One was that he had met an American warship——

And the other! It was far less probable, but it was possible, and terrible. They might have fallen into the hands of the enemy.

But whatever was the case, there was nothing for Clif to do but obey the signals. He could not run and he could not fight.

"If I only knew," he thought, anxiously.

And then suddenly he learned; for a faint voice was borne over to him through the gale. It was a voice that spoke English!

"Ahoy there!" it rang.

And Clif roared back with all his might!

"Ahoy! What ship is that?"

And his heart gave a throb of joy when he heard:

"The United States cruiser Nashville. Who are you?"

"The Spanish merchantman Maria, in charge of a prize crew from the Uncas!"

Whether all that was heard in the roar of the storm Clif could not tell; but he put all the power of his lungs in it.

He knew that the story would be investigated.

And so he was quite prepared when he heard the response:

"Lay to and wait for a boarding party."

And quick as he could move Clif sprang to the pilot house, and signaled to stop, and the vessel swung round toward the stranger.

The die was cast, for good or evil. They had given up!

For perhaps five minutes there was an anxious silence upon the vessel. Every one was waiting anxiously, while the ship rolled in the trough of the sea and shook with the crashes of the waves. Her small crew were picturing in their minds what was taking place out there in the darkness, their comrades struggling to get a small boat out in that heavy sea.

And then they fancied them buffeting their way across, blinded by the spray and half swamped by the heavier waves.

"They can't be much longer," muttered Clif, impatiently.

"Ahoy there! A ladder!"

It seemed to come from right underneath the lee of the merchantman. And it was shouted in a loud, peremptory tone that was meant to be obeyed. A moment later the rope ladder was flung down. Clif peered over the side when he dropped it.

He could make out the shape of the boat tossing about below; he could even distinguish the figures of the men in the boat.

And then he made out a man climbing hastily up.

He stepped back to wait for him. He saw a blue uniform as the officer clambered up to the deck.

And then suddenly he stood erect, facing Clif.

The cadet took one glance at him and gave a gasp of horror.

It was a Spanish officer!

And he held in one hand a revolver and was aiming it straight at Clif's head.