osened her forward gun.

The shell went wide, but it brought immediate action from the submarine
commander. Evidently he had no mind to try and torpedo the little craft,
realizing, perhaps, that did he sink one the other would destroy him.

Motioning the other three men on deck before him, he sprang toward the
little conning tower, bent on flight.

At this juncture the _Lion_ came within range and her forward gun spoke
loudly. The shell kicked up the water a few yards from the submarine.

"Hoorah!" came the British cry.

"A little soon to cheer," muttered Frank to himself, as he stepped
forward to take his second shot at the submarine.

"Boom!"

The gun spoke sharply.

Ahead there was a terrible crash. The German submarine seemed to soar in
the air like a skyrocket, and came down in a thousand pieces.

Frank's one well-directed shot had ended the battle.

Then a mighty cheer went up from the men of the mosquito fleet, in which
the passengers aboard the _Glasgow_ joined with a will.

Jack sprang forward and gave his chum a resounding slap on the back.

"That's what I call shooting," he declared fervently.

"Good work, Frank," said Lord Hastings quietly, stepping forward. "An
excellent shot."

Masses of wreckage floating upon the surface of the sea were all that
was left of the German submarine, with here and there a few floating
bodies. Soon these disappeared and there was nothing to indicate that an
under-sea craft had so recently been near.

From aboard the _Lion_, Commander Thompson signalled his compliments to
The _Hawk_.

"And now I suppose we will go back again," said Frank to Lord Hastings.

"Well, no," was the reply. "The _Glasgow_ is not safe yet. There may be
other submarines in these waters. I should say that we shall escort her
all of a hundred miles."

"What I would like to know," said Frank, "is why her commander, instead
of trying to escape at once, didn't launch a torpedo or two. He might
have disposed of one of us."

"But the others would have surely done for him," said Lord Hastings. "He
probably figured he could submerge before we could hit him."

"He guessed wrong that time," declared Frank.

"Rather," agreed Jack with a smile. "There is no use talking, Frank, you
are some boy when it comes to shooting."

All that afternoon the motorboat flotilla trailed the _Glasgow_; but
until nightfall no other German submarine had appeared. An hour after
nightfall, Commander Thompson gav