186 GARRISON ARTILLERY WARFARE. 
again with a sufficient margin of day-light to enable them to get out of 
striking distance of the defending torpedo-boats before darkness sets 
in. 
If, during their operations then, any of their ships are disabled, in 
the event of an unsuccessful action, these must fall into the defender’s 
hands, as they will perforce be left to shift for themselves, and are thus 
exposed to capture or destruction. ! 
From this it will be seen that this form of attack on ships lying 
under the guns of a Coast Fortress provided with first-class and other — 
torpedo-boats is difficult and dangerous. Where the lines of approach 
are few and restricted the risk is further increased, but where tlic 
attackers have to fight their way in through a narrow channel, defended 
by modern skill, and fight their way out again the risk becomes 
enormous. 
The task of the defenders will be to use their utmost endeavours to 
defeat the “secondary ” attack by delaying the advance of the attack- 
ing fleet, taking into consideration the importance of time to it, and 
inflicting the greatest possible damage to it during its advance, but 
once the “ primary ” attack has developed by the appearance of the 
attacking torpedo-boats within effective range, every other considcra- 
tion must give way to the vital necessity of destroying them before 
they can arrive at striking distance of the ships they menace. 
The most dangerous form of torpedo warfare and the most to be 
dreaded is when torpedo-boats advancing from a distant base, under 
cover of darkness and thick weather, steal in unperceived to effective 
torpedo range. 
In this form of attack the chances are greatly in favour of the 
attackers, and the only real safeguard would be to so restrict the lines 
of approach as to force the torpedo-boats to pass through narrow 
openings in a specially constructed mole or breakwater behind which 
the protected ships are at anchor. The approaches to these openings 
should be brilliantly illuminated by electric light, while the openings 
should be protected by Q.F.’s and heavy guns firing case shot and 
closed by floating booms or chains drawn across them. 
From this then it would appear that ships anchored under the guns 
of a Coast Fortress, which is provided with first-class and other torpedo- 
boats, are not exposed to the first form of torpedo attack by night. 
They are so exposed by day. 
Tf no defending torpedo-boats exist they are exposed to this form of 
attack by day and night. 
They are always exposed to the second form, unless effectually pro- 
tected from it. 
The other phase of a “primary” attack may be considered under 
two headings. 
(1.) Boat attacks pure and simple. 
(2.) Attacks on booms and mine-fields. 
As regards (1.) These attacks may assume a variety of forms, 
amongst them we may instance :— 
(a) An attempt to land a party undetected at one place to destroy 
