with it."

They had little time to ponder over the possibilities of gastronomic
disturbances, for there was much going on that occupied their attention.
The _Dewey_ was now running entirely submerged, testing out her
electric batteries.

"How do they steer the vessel down here under the sea?" asked Jack.

"By the gyrocompass," answered Bill Witt, pointing to where Executive
Officer Binns and Commander McClure stood in the conning tower. "We
are running blind down here, except that the skipper knows from his
compass which direction we are going, and he has charts that tell him
the depth of the sea at this point. They know the longitude and
latitude and can easily determine on their maps and charts just where
we are."

"How deep down can we go?" inquired Ted.

"Most of the boats have to be tested at a depth of two hundred feet
before they are accepted by the government from the builders," replied
Bill. "But you can bet your life we don't often go down that far.
When we do, the water is oozing through the thin steel hull and
dropping in globules from the sides and top of the vessel. From sixty
to a hundred feet is our average plunge."

Even at that moment the boys noticed that the _Dewey_ was "sweating"
a little bit, the vaulted steel above them, coated with a composition
that contained cork, being dotted here and there with drops of water.
Jack craned his neck to look at the depth dial and noted the indicator
hand was pointing at seventy-two feet.

Mess was served at noon while the _Dewey_ kept on her run. Coffee and
biscuits made up the frugal meal this time, the officers and crew
being anxious to prove the submersible ready for any emergency call
that Uncle Sam might make, and not desiring to spare the men from
their posts longer than possible.

All afternoon the _Dewey_ ploughed the waves, sometimes running
submerged, other times on the surface. About five o'clock the boys
perceived the lighthouse at the bay entrance, and soon they were
back in the navy yard. Their letters home that night thrilled with
accounts of their first dive under the ocean, and in their dreams
the boys were sharing all manner of wonderful exploits against the
foe on the boundless sea.

For several weeks the Brighton recruits were kept busily at the
business of mastering submarine navigation. In the distribution of
the crew throughout the vessel Jack and Ted found themselves assigned
under the leadership of Chief Gunner Mowrey