Buenos Ayres with a cargo of
flour for London was treated in the same manner off Margate by the
'U-13'!"

"Isn't it a little strange that the submarine should have attacked a
peaceful merchant vessel?" inquired Jack. "That isn't war!"

"Evidently it is the intention to blockade all English ports and shut off
the food supply of the nation," ventured Ned. "You see the article
relates that all the ships were loaded with food and destined to English
ports. It must be a blockade movement!"

"Here's an account," announced Harry, "that says a steamer was hailed by
a submarine a few miles off the Lizard Head. It escaped by its superior
speed, but only by a narrow margin, for the submarine launched a torpedo
that barely missed striking the after portion of the ship!"

"Maybe it was the same little old 'U-13,'" suggested Jimmie.

"Oh, you 'U-13'!" laughed Jack. "You're some boat, all right!"

"Say!" shouted Jimmie, jumping quickly to his feet. The boy glanced about
the group with startled looks. "What about that 'U-13' package? Do you
suppose it was intended for the submarine?"

The boys exchanged puzzled looks. Perplexity was expressed in every face.
A look of worry began to appear on Ned's countenance.

"I wonder who Mackinder is and what he has to do with that package," the
lad said presently. "Boys, we're surely stumbling into a mess of
something. We'll have to be careful!"

"Captain," demanded Jimmie, turning to von Kluck, "what do you know about
this 'U-13' business? What is the 'U-13'?"

Leaning back in his chair the captain drew a long breath. He filled a
great pipe from a capacious pouch. Gravely he packed the tobacco into the
immense bowl, accompanying the procedure with sundry shakes of his head.
Not until the pipe was drawing freely did he reply.

"Ach, id vas vot der Deutsch say it 'Unterseeboot'! You English say it
submarine! Und dot liddle schip goes 'Boom'! und down goes der big schips
under der vasser! Und dey stay, too!" he concluded.

"Yes, we know that," assented Jimmie, punctuating his statement with a
poke at the paragraph he had just read, "but who owns it?"

"Vhell, der Chermans dey claim to haf a big share in id!"

"Then if we start out for England in this Lena Knobloch of yours how do
we know that the 'U-13' won't come along and take a poke at us just out
of pure spite?" questioned the lad.

"Vhell, maybe she vill," agreed von Kluck, between puffs. "Bud if you
vhas like me, you iss will