Dave was already at the door, trying to force it open. But he might
almost as well have tried to lift one of the twelve-inch guns of the
battleship "Massachusetts."

"We're locked in--that's sure!" gasped Dalzell, almost dazed by the
catastrophe.

"And what's more, we won't get out in a hurry, unless we can make some
of our classmates hear," declared Dave.

For the next half minute they yelled themselves nearly hoarse, but no
response came.

"What could have been that little cockney's purpose in playing this
shabby trick on us?" demanded Farley.

"Perhaps the cockney thinks we're admirals, with our pockets lined with
gold. Perhaps he and some of his pals intend to rob us, later in the
evening," proposed Dan, with a ghastly grin.

"Any gang would find something of a fight on their hands, then,"
muttered Dave Darrin grimly.

All three were equally at a loss to think of any explanation for such a
"joke" as this. Equally improbable did it seem that any thugs of the
town would expect to reap any harvest from robbing three midshipmen.

Desperately they turned to survey their surroundings. The shed was an
old one, yet strongly built. There were no windows, no other door save
that at which the three middies now stood baffled.