nce. At all events, the steamship goes in peace and the
submarine comes to the surface. The commander is glad, because electric
power must be used when the vessel is moving under water and there must
be no waste of this essential element.

So the submarine proceeds on her way, wallowing and tumbling through the
heavy graybacks of the North Sea. At length after fifty-four hours the
necessity of sleep becomes apparent. The ballast-tanks are filled and
the craft slowly descends to the sandy bottom of the sea. It is
desirable that the crew go to sleep as quickly as possible, because when
men are asleep they use less of the priceless supply of oxygen which is
consumed when the boat is under water. However, the commander allows the
men from half an hour to an hour for music and singing. The phonograph
is turned on and there on the bottom of the North Sea the latest songs
of Berlin are ground out while the crew sit about, perhaps joining in
the choruses--they sang more in the early days of the war than they do
to-day--while the officers sit around their mess-table and indulge in a
few social words before they retire.

In the morning water from the tanks is expelled and the boat rises to
greet a smiling sea. Also to greet a grim destroyer. The war-ship sees
her as she comes up from a distance of perhaps a mile away. All steam is
crowded on while the leaden-gray fighter--the one craft that the
submarine fears--makes for her prey. Sharp orders ring through the
U-boat. The tanks are again filled, and while the commander storms and
ejaculates, everything is made tight and the vessel sinks beneath the
surface. The electric-motors are started and the submarine proceeds
under water in a direction previously determined, reckoned in relation
to the course of the approaching destroyer.

Presently comes a dull explosion. The destroyer arriving over the spot
where the undersea boat was last seen, has dropped a depth-bomb, which
has exploded under the surface at a predetermined depth. The submarine
commander grins. The bomb was too far away to do damage, although the
craft has trembled under the shock. There comes another shock, this time
not so palpable. Eventually all is quiet.

For an hour the submarine proceeds blindly under water, and then
cautiously her periscope is thrust above the surface. Nothing in sight.
Orders sound through the vessel and she rises to the surface. She could
have remained below, running under full headway, for