COAST DEFENCE AGAINST TORPEDO-BOAT ATTACK. 
Men do not 
know what they 
are expected to 
see. 
depends on good lookouts that every encouragement should be given 
to capable men. An ordinary sentry does not meet the case. 
E Vht The vision of some of the men was found to be ex¬ 
traordinarily good at night and very correct. Such 
men should be noted, but it is impossible to pick them out without 
practice. Their ability in this respect seemed to have no connection 
with their ordinary avocation. Clerks from offices were sometimes as 
good as any. At the commencement of manoeuvres 
the great majority do not know the appearance by 
night of what they are looking for; a torpedo-boat in 
the moonlight, electric beam, or in comparative dark¬ 
ness, seen from a high site is a very different object 
to what they know of it rushing about by day. It is difficult to 
impress on lookouts that a torpedo-boat is most deadly and difficult 
for them to deal with when she is stealing about dead slow leaving no 
wake. In almost every case in which torpedo-boats are made out 
without the aid of lights they are going at speed. Then their wake 
Wake often hundreds of yards behind them is first seen from a 
seen first. height and, followed by the eye, leads to the boat 
itself. Sometimes a spark flies from the funnel and 
catches a lookout's eye, almost unconsciously, directing his attention 
particularly to that part of the sea area where he eventually detects 
the boat, but even then it is generally the wash of the sea against the 
boat, or her wake, that he sees before he can satisfy himself as to the 
form of the boat itself. 
On exactly the same principle that an offensive 
defence is very much more effective than a passive 
defence, a wandering electric beam is much more 
dreaded by attacking boats than a fixed beam, though 
the latter are what are mostly placed by the Engineers for Artillery 
use. When operations are really prolonged sufficiently to closely 
resemble actual war conditions, many points are brought to notice 
that escape the more limited experience of experimental committees. 
No doubt in one or two localities fixed beams have answered admir¬ 
ably, under specially skilled management, for an hour or two of 
experimental trial, with the result that they have been recommended 
for universal adoption; but in wearying prolonged trials, boats are 
found to easily slip through such fixed beams unobserved. It is a 
mere question of time. They lie patiently, even for half the night, 
until the light requires adjustment (it is a very cleverly managed light 
that does not require it frequently), and they are through in a few 
seconds—or, if the light is low sited they go out to sea a mile or two 
and pass through the blind angle caused by the curvature of the 
earth. In nine cases out of ten the belief inculcated in a fixed ray 
has greatly aided the boats ; for if there is a wandering ray on the 
side of the fixed beam away from the boat, the light of the latter 
interferes with the wandering beam, while if boat and wandering 
beam are on the same side of the fixed ray, the wandering beam has 
displayed a tendency in most hands, to leave the neighbourhood of 
8 
Wandering 
versus fixed 
beams. 
