similar feeling comes over one
who walks the narrow path down the centre of the machinery
compartment of a submarine. He seems hedged about by mysterious
apparatus a touch of which, or even an accidental jostle may release
powerful and even murderous forces.

While the submarine is under way, submerged, the operator at every
piece of individual machinery stands at its side ready for action.
Here are the gunner's mates at the diving rudder. They watch
steadily a big gauge on which a needle which shows how deep the boat
is sinking. When the required depth is reached swift turns of two
big brass wheels set the horizontal rudders that check the descent
and keep the boat on an even keel. Other men stand at the levers of
the Kingston valves which, when open, flood the ballast tanks with
water and secure the submergence of the boat. Most of the underwater
boats to-day sink rapidly on an even keel. The old method of
depressing the nose of the boat so as to make a literal dive has
been abandoned, partly because of the inconvenience it caused to the
men within who suddenly found the floor on which they were standing
tilted at a sharp angle, and partly because the diving position
proved to be a dangerous one for the boat.

In the early days of the submarines the quarters for the men were
almost intolerable. The sleeping accommodations were cramped and
there was no place for the men off duty to lounge and relax from the
strain of constant attention to duty. Man cannot keep his body in a
certain fixed position even though it be not rigid, for many hours.
This is shown as well at the base ball grounds at the end of the
sixth inning when "all stretch" as it was in the old time underwater
boats. The crews now have space in which to loaf and even the strain
of long silent watches under water is relieved by the use of talking
machines and musical instruments. The efficiency of the boat of
course is only that of her crew, and since more care and more
scientific thought has been given to the comfort of the men, to the
purity of the air they breathe, and even to their amusements, the
effect upon the work done by the craft has been apparent. Ten years
ago hot meals were unthought of on a submarine; now the electric
cooker provides for quite an elaborate bill of fare. But ten years
ago the submarine was only expected to cruise for a few hours off
the harbour's mouth carrying a crew of twenty men or less. Now it
stays at sea sometimes for