"Temeraire."

But with the increased charges and length of breech-loading guns, a
further change was desirable, and after some trials a system of
disappearing mountings (see Ordnance: _Garrison Mountings_) was adopted
into the British service.

A word must be now said on the size of gun finally adopted. At first
muzzle-loaders figured largely in the British defences, even though
these were planned on modern ideas; and even in 1906 muzzle-loading guns
still existed and were counted as part of the defences. The sizes of
these guns varied from the 32- or 64-pounder, of which the nomenclature
depends on the weight of the shell, to the 7-in., 9-in., 10-in., 11-in.,
12.5- and finally 17.25-in., the size indicating the calibre. Such a
multiplication of sizes was due to gradual improvements in the science
of gun manufacture, each advance being hailed as the last word to be
said on the subject, and each in turn being rapidly made obsolete by
something bigger and better. But with the improvements in gun design
which followed the introduction of breech-loaders, the types used in
coast defence were gradually narrowed down to two, the 9.2-in. and the
6-in. guns. Of these, the 9.2-in. was considered powerful enough to
attack armour at any practical range, while the 6-in. gun was introduced
to deal with lightly armed vessels at shorter ranges where 9.2-in. guns
were unnecessarily powerful.

A few larger guns of 10-in. calibre have actually been used, but though
the British navy has now sealed a 12-in. 50-ton gun as the stock size
for battleships, for the heavy armament of the coast defences the War
Office remain faithful to the 9.2-in. calibre, preferring to develop
improvements rather in the direction of more rapid fire and higher
muzzle velocity.

The 6-in. has also been retained and is extensively used for the smaller
ports, where attack by powerful vessels is for various reasons
considered improbable.

The design of the forts to contain the guns necessarily varied with the
type of defence adopted, and the duties which the forts had to fulfil.
These duties may be said to be twofold, first to facilitate the service
of the guns, and secondly to protect the guns and their detachments from
damage by fire from ships, or by close attack from landing parties. The
service of the gun is provided for by a system of cartridge and shell
magazines (see AMMUNITION), well protected from fire and suitably
arranged. The shelters for the gun