ain, and with throbbing engines the steamers settled down
to a trial of speed.

"If we could only imagine that as a starting gun this would make a
first-rate yacht race," said Bert, after they had been running for some
minutes.

"Yes, and for a richer stake than ever a yacht raced for before,"
replied the captain, who had overheard the remark. Harry thought of the
portrait of the beautiful girl that lay next the man's heart, and
wondered if he meant her, but when he remembered the ringing defiance in
his voice as he shouted back to the Spaniard, "Viva, Cuba Libre," he was
inclined to believe that the man's spirit of patriotism rose superior to
his love just now.

By this time the veil of mystery that had hung over the ship and her
purpose had been pretty well lifted by the sequence of events, and the
boys were convinced that they were a part of some secret mission against
Spain in the interests of Cuba.

Harry had little time for speculation as to the motives that inspired
the captain, for another puff of white smoke appeared at the gunboat's
bow and a shot whistled by close to the starboard rail. The _Mariella_
had been slowly drawing away from her pursuer, and the Spanish commander
evidently feared his prey would escape.

Suarez, on the bridge, turned anxiously aft as if expecting
instructions, but Captain Dynamite only set his lips into that firm,
straight line and raised his glasses to watch the enemy's movements.

Another puff of smoke, a sharp report, and a shot struck the water one
hundred yards astern, but in direct line with the _Mariella_.

"They've got the direction, but not the range," muttered the captain.
"Hard a-starboard, Suarez, for half a minute, and then take your course
again. We'll give that gunner another guess."

The _Mariella_ swung to starboard just enough to take her out of the
direct course of her pursuer.

"Now, try it again, Mister Sharpshooter," sung out the captain, although
the Spaniard was by this time far out of range of his voice. "It will
take you some time to pick up your target once more."

The Spaniard sent two other shots after them in quick succession, but
they fell harmlessly to port. The quick swinging of the _Mariella_ out
of her course had disconcerted the gunners.

"Don't you think you youngsters better go below?" said the captain,
joining the boys, while he calmly rolled a cigarette. "I haven't much
respect for their marksmanship, but you never can tell where a