inches thick, and each carried two 80-ton guns, firing a
1700-pound shot to a distance of eight miles. These monster
muzzle-loading guns were loaded from outside the turret, by means of
hydraulic machinery. The armour on the sides was 2 feet thick, and the
vessel was divided into 135 compartments, so that she would not be
readily sunk. The _Inflexible_ was the last of the turret-ships
properly so-called. She was not the success that had been hoped; her
engine power, which gave only 12 and a half knots, had been sacrificed
to obtain heavier armament and protection, and as she was slower than
much older ships, she was laid aside before vessels launched earlier
than she was. About this time, the combination of several important
factors worked a revolution in warship design. The Russo-Turkish war of
1878-79, taught that a torpedo was a more important element in naval
warfare than had been imagined. Launches going at the rate of 18 or 20
miles an hour, covered a mile in about three minutes, and if they
attacked at night, were so small, quick-moving, and indistinguishable,
that they could attack the most powerful battleship with little risk of
being hit by the snap shots of the few slow-firing heavy guns, with
which modern ships were armed.

The machine gun was first introduced to meet this danger; it could send
a continuous shower of rifle bullets at the approaching boat, and riddle
and sink her before she got near enough to do mischief; but when torpedo
boats began to be armoured with iron plates, proof not only against
rifle bullets, but even against the heavier Hotchkiss and Nordenfeldt
half-pounder guns, except at very close ranges, it was seen that an
armament of small guns was desirable to repel torpedo boats, or to be
used against unarmoured cruisers, whose superior speed would soon take
them out of danger from the slow-firing heavy guns. Another factor was
the introduction of longer guns, and what are termed "slow burning"
powders. These last do not explode with such sudden violence as the
ordinary powder, so that there is less sudden strain on the gun, while a
steadier pressure on the shot is kept up. The long gun enables the
pressure of the gases formed by the burning powder to act longer on the
shot, with the result that a higher velocity is given to it, not only
increasing its range, but also its penetrative power.

The result of these improvements was to some extent a repetition of what
had taken pla