DEFENCE OF A COAST FORTRESS. 
29 
Aerial torpedoes, such for instance as the Zalinski or G-raydon, 
being closely allied to guns, cannot, so far as we know, be warded off. 
Their guns should be placed high up when possible. They have the 
advantage of not obscuring their fighting lights, and it matters little 
whether they strike or not, within limits; their target is a large one. 
All these projectiles have a very low velocity compared with guns 
proper. They should not be used for the defence of mine-fields. 
(3).—Electric Light. 
Though guns could, quite as easily as mines, be worked semi- Working 
automatically, that is to say, be made to strike with their projectiles maticaiiy*. 0 " 
any point, in the dark, touched by a ship, yet such a system would 
have all the disadvantages of the submarine mining system, inasmuch 
as it would be complicated, intricate, and therefore uncertain, while it 
would be dangerous to friendly shipping, and ships would disarrange 
the gear by accident. 
Personally, I have little faith in the efficiency in war of exceedingly No faith to 
complex mechanism, liable to fail if any one of its numerous ramifi- compiex edm 
cations get injured. mechanism. 
But it may, nevertheless, be most advisable to keep up such mechanism still these 
as a last resource, for use when simpler means fail owing to unusual a™ge- ated 
conditions. The worst of complicated systems is that altogether too “ e en ke pfc m JJ 
much faith is placed m them, and the necessary training for effectively a *> aiast re- 
working a simple but surer method is apt to be neglected. 
If night could be turned into day the gun defence remains unassail¬ 
able, but guns fail in darkness and fog without elaborate and intricate 
arrangements. 
The electric light under favourable conditions enables guns and mov¬ 
ing torpedoes to see their prey, but the light is, unfortunately, easily 
blinded by fog or smoke. Fog is, therefore, favourable for attack and 
bad for defence. Smoke can easily be got over by multiplying the 
lights and placing them, like the guns in dispersed stations, with a 
capability of concentration of beams. 
There should be plenty of search and fighting lights, or the great 
power of gun defence will never be realised. At present gun defence lights, 
is more or less thrown away for a large portion of every 24 hours. 
Fixed beams are more favourable to an enemy than moving beams, 
and, I think, they would be easy to dodge. It is difficult to prevent 
discovery by a moving light steadily fixed and worked. 
The fighting lights by which gun defence is made effective should 
be as much part and parcel of the gun defence as are position and 
range-finders. They are not so at present. 
If fighting lights are placed on heights there is no reason they should 
not act as range-finders to the guns and they would less often be 
obscured. Search lights should be on low sites. 
The more lights there are the more complete must be the control 
exercised over them by a Section Commander. 
(4).—Submarine Mines. 
Submarine mines are obstacles merely, they do not constitute an 
active attacking defence, and they depend for their existence on the 
