y," muttered Captain Jack, bitterly.
"They haven't beaten us, so far, by a single point."

"I suppose they're hoping they will to-day, whatever the test is to
be," muttered Hal Hastings.

Fifteen minutes more passed. Then a little flock of six-oared cutters
left the side of the gunboat "Oakland." In the stern-sheets of each
cutter sat a naval officer in uniform.

"There's Lieutenant Danvers," cried Jack, eagerly. "He brings us our
instructions, whatever they are."

In a few moments more Danvers was along side, making his way up to the
platform deck. In his right hand Danvers carried an official looking
sealed envelope.

In his eager curiosity Jacob Farnum extended a hand to take the envelope,
but Danvers drew it back.

"Pardon me," murmured the shipbuilder, confusedly. "I should have known
better. The communication is, of course, for the captain."

Danvers turned the envelope over to Captain Jack Benson, who broke the
seal, drawing out the paper enclosed. This is a part of what the
submarine boy read aloud:

_"'The Navy Department has just reported, by wireless, that a
semi-submerged derelict, evidently that of a three-master schooner, is
drifting in the paths of navigation at a point 385 miles southwest by
south of this present station. The Department suggests that it would
afford an example of practical use for submarines, if those now on this
station would accompany a gunboat, at full speed for cruising, and
attempt to discover and blow up this derelict.'"_

"Great!" glowed Eph. "I vote for it."

"So do those on the other boats, if the observable excitement is to be
taken as an indication," laughed Mr. Farnum.

"This letter goes on to request," announced Benson, "that the commander
of each submarine willing to enter this affair signal to the 'Oakland'
by hoisting the signal 'Ready.' Do you hear that, Eph?"

Somers made a dash for the signal chest. In another moment the
appropriate bit of bunting was fluttering on the halliard at the top of
the signal mast.

"We are directed," Jack read on, "to be ready within thirty minutes. We
must follow the 'Oakland' down the bay at a cruising speed of sixteen
miles an hour. Once out of the bay, the 'Oakland' will signal our
formation to us."

"Do you see the boat the Rhinds signal is going up on?" laughed Hal
Hastings. "It is going up on the submarine 'Thor.' According to the old
Norsemen tales Thor was The Thunderer--also the fellow who struck with