ourse, be designed for that purpose
before being constructed; but usually hospital ships were originally
passenger ships, and were adapted to hospital uses later.

The menace of the destroyer--owing to the sea-worthiness which this
type has now achieved, and to the great range which the torpedo
has acquired--has brought about the necessity of providing external
protection to the battleships; and this is supplied by a "screen"
of cruisers and destroyers, whose duty is to keep enemy destroyers
and (so far as is practicable) the submarines at a safe distance.

We now see why a fleet must be composed of various types of vessels.
At the present moment, the battleship is the primary, or paramount
type, the others secondary, because the battleship is the type
that can exert the most force, stand the hardest punishment, steam
the farthest in all kinds of weather, and in general, serve her
country the best.

Of course, "battleship" is merely a name, and some think not a
very good name, to indicate a ship that can take the part in battle
that used to be taken by the "ship of the line." The reason for
its primacy is fundamental: its displacement or total weight--the
same reason that assured the primacy of the ship of the line. For
displacement rules the waves; if "Britannia rules the waves," it
is simply because Britannia has more displacement than any other
Power.

The fleet needs to have a means of knowing where the enemy is, how
many ships he has, what is their character, the direction in which
they are steaming, and their speed. To accomplish this purpose,
"scouts" are needed--fast ships, that can steam far in all kinds
of weather and send wireless messages across great distances. So
far as their scout duties go, such vessels need no guns whatever,
and no torpedoes; but because the enemy will see the scout as soon
as the scout sees the enemy, and because the enemy will try to
drive away the scout by gun and torpedo fire, the scouts must be
armed. And this necessity is reinforced by the necessity of driving
off an enemy's scouts.

In foreign navies the need for getting information in defiance
of an enemy's attempts to prevent it, and to drive off the armed
scouts of an enemy, has been one of the prime reasons for developing
"battle cruisers," that combine the speed of the destroyer with
the long steaming radius of the battleship, a battery almost as
strong, and a very considerable protection by armor.

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