d it was
soon found that with the guns and gunners available, hits could only be
obtained by running in to short range and dealing with one gun at a
time.

This new principle was not at once recognized, for systems die hard,
and much money and brains were invested in the then existing system. But
a modern school was gradually formed; a small group of engineer officers
under the headship of Sir Andrew Clarke, the then inspector-general of
fortifications, took the matter up, and by degrees the new views
prevailed and the modern school of coast defence came into being between
1881 and 1885. Meanwhile important changes had been developing in the
gun, the all-important weapon of coast defence, changes due mainly to
the gradual supersession of the muzzle-loader by the breech-loader. The
latter gave the advantages of quicker loading and more protection for
the gun detachment over and above the technical improvements in the gun
itself, which gave higher muzzle velocity, greater striking effect and
longer effective range.

All this reacted on the general scheme of coast defence by enabling the
number of guns to be reduced and the distance between forts increased.
On the other hand, the ships, too, gained increased range and increased
accuracy of fire, so that it became necessary in many cases to advance
the general line of the coast defences farther from the harbour or
dockyard to be defended, in order to keep the attackers out of range of
the objective.

Another change resulted from an improvement in the method of mounting.
Even in the older days discussion had arisen freely on the relative
merits of barbette and casemate mounting. In the former the gun fires
over a parapet, giving a larger field of view to the gun-layer, and a
larger field of fire for the gun, with, however, more exposure for the
detachment. The latter gives a restricted view and greater safety to the
layer, but unless the casemate takes the form of a revolving turret, the
arc of fire is very limited.

An important advantage of the barbette system is its cheapness, and thus
in order to obtain with it concealment, suggestions were made for
various forms of mounting which would allow of the gun, under the shock
of recoil, disappearing behind the parapet to emerge only when loaded
and ready for the next round. A mounting of this description for
muzzle-loading guns, designed by Colonel Moncrieff, was actually in use
in the defences of Alexandria and in H.M.S.