DEFENSE AGAINST ATTACK BY SEA.
In attacking a hostile coast a fleet may either direct its efforts against a fortified harbor, or at tempt to take possession of unfortified coast re gions. The problem for the defense, therefore, naturally resolves itself into the defense of fortified places, and the defense of unfortified coast regions. The phases of the attack by sea in the first ease are, in order. the removal of the outer obstructions, the reconnaissance, the artil lery duel, the removal of the inner obstructions. the forcing of the entrance, and, final]'', land ings to obtain full possession of the forts. The phases of the defense will correspond.
Before endeavoring to ascertain the position of the guns of the defender, the attacking tleet will seek to destroy outer obstructions, in order to get possession of the outer bay, and, if the opportunity should offer, to force the passage. The torpedoes of the mine fields and the gulls of the batteries on shore are complementary means of defense, each inadequate without the other. The obstructions are a passive means, but only become real obstacles when protected by the coast artillery; on the other hand, the latter alone, without the obstructions, cannot prevent the enemy from the harbor. The outer mine field is so important that there will be a serious struggle over it, for, once the attacking fleet passes over it, its further work is greatly shn plified.
The defender. therefore, must lie constantly on the alert, especially at night, when the search lights are continually in use lighting up the fore ground beyond the mines. All approaching ships arc tired upon by the artillery. and since the enemy will probably not attempt to remove the mines with any but his smaller vessels, such as to•pedo-boats (since the outer mine field is placid intentionally in the field of greatest effect of the
fense remain close up to the mine fields in order to fight the enemy's torpedo-boats while they are endeavoring to remove the mines. The counter attacking torpedo flotilla must he followed by one or two mine-laying ships, for repairing the dam aged mine lines.
The attacker's object in reconnaissance is to obtain full and accurate knowledge of the location and power of the defender's guns of all calibres and kinds, the position of the torpedo batteries and mine observation stations, and finally to find out what new gun positions have been erected for the war. The defense, therefore, endeavors to veil all his batteries that cannot be readily seen from the sea, and to still further deceive the en emy lie erects a number of small batteries. Batteries with disappearing carriages and mortar batteries have here a great tactical advantage, because they can be readily concealed. While the fleet is reconnoitring, therefore, beyond the outer mines, only such guns of the defense open fire as cannot be concealed, but as the ships come near the mines, and take up the formation in eolunm, the other batteries open fire and with armor-pierc ing projectiles. Each battery is assigned to a different ship, on which it concentrates its fire, and which it follows until it is sunk or gets be yond armor-piercing range. The coast artillery is assisted in this work by the guns of the ships that may be in the harbor, these vessels moving inside the mine field on lines perpendicular to the enemy's line of advance, making the greatest possible use of their artillery, the torpedo-boats making counter-attacks when possible. The in fantry garrison of the fortified place is posted on outpost along the shore, and prevents the enemy from landing reconnoitring parties, or fires on torpedo-boats sent along the shore to reconnoitre. In ease the mine obstruction was removed by the enemy before his reconnaissance, the defender's larger vessels cannot take so advanced a position close up to the mine field, and as soon as the at tacker approaches the latter the defender must bring all his guns into action.