power of dealing with unarmed or lightly armed vessels, that we relied for
our first line of defence against invasion. These latter duties were of
course exceptional, and the Navy List did not carry as a rule sufficient
numbers for the purpose. But a special value of the class was that it was
capable of rapid and almost indefinite expansion from the mercantile
marine. Anything that could carry a gun had its use, and during the period
of the Napoleonic threat the defence flotilla rose all told to considerably
over a thousand units.

Formidable and effective as was a flotilla of this type for the ends it was
designed to serve, it obviously in no way affected the security of a
battle-fleet. But so soon as the flotilla acquired battle power the whole
situation was changed, and the old principles of cruiser design and
distribution were torn to shreds. The battle-fleet became a more imperfect
organism than ever. Formerly it was only its offensive power that required
supplementing. The new condition meant that unaided it could no longer
ensure its own defence. It now required screening, not only from
observation, but also from flotilla attack. The theoretical weakness of an
arrested offensive received a practical and concrete illustration to a
degree that war had scarcely ever known. Our most dearly cherished
strategical traditions were shaken to the bottom. The "proper place" for
our battle-fleet had always been "on the enemy's coasts," and now that was
precisely where the enemy would be best pleased to see it. What was to be
done? So splendid a tradition could not lightly be laid aside, but the
attempt to preserve it involved us still deeper in heresy. The vital, most
difficult, and most absorbing problem has become not how to increase the
power of a battle-fleet for attack, which is a comparatively simple matter,
but how to defend it. As the offensive power of the flotilla developed, the
problem pressed with an almost bewildering intensity. With every increase
in the speed and sea-keeping power of torpedo craft, the problem of the