26 COAST -DEFENCE AGAINST TORPEDO-BOAT ATTACK. 
cease fire. C at once ranges ; D’s bell is touched half-a-minute after 
and recommences fire; having* been short before, D can probably now 
range as C’s splashes should be close to the boat, but if not C is 
stopped for a very short time, and so on, the fire of the batteries 
which have had the chance of ranging being effective out of all 
comparison with the unranged batteries. With auto-sights the system 
should be doubly valuable, as then once “ on ” will mean always “on,” 
and a boat appreciating the increased accuracy will turn and go to 
sea, or rush for dark water as at K if it knows of it. Good practice 
from high sited 12-pr. Q.F. guns up to 5,000 yards may in this way 
be calculated on; at ranges of 4,000 and upwards however, rather 
more than half a minute must be allowed for ranging owing to 
increased time of flight. At long ranges there is not so much 
occasion for hurry, you may not so certainly sink the boat, but she 
can do no harm. 
Suppose the boat t.b. had not been picked up by the wandering ray 
and, working in concert with others, she had been specially detailed 
to get as close as possible to the light B with a view to a combined 
attack from the north, through the ray B U, on the objective ships. 
She runs to t.b. 2, waits till the carbon of B needs adjustment and 
passes through to the dark water at K, say to t.b. 3, where she waits 
in perfect security, B and S being fixed lights, until the carbon of S 
also needed a change. Then she passes to the dark water l to rest 
until one or more of her consorts join her when, the rush being 
decided on, she moves to t.b. 4 and fires shadow-laying at the light, 
attracting much attention on herself. Whether successful or not in 
destroying the light with her small Q.F.'s and rifles in a minute or so, 
she and her consorts, each a few hundred yards apart, must make 
their rush and, if batteries are working independently, with a good 
chance of success. A, B, C , D and one gun of E, all see them, but there 
is a strong tendency always exhibited to fire at the most easily seen 
boat, and one of the three boats at any rate should get home. One 
boat is left out with instructions to show showers of sparks from her 
funnel and attract the attention of the wandering beam as soon 
as she hears t.b. 4 commence firing at the light. The central 
station, however, knowing her range and that she cannot get home 
for several minutes, neglects her and turns the wandering ray on the 
real attack preventing the rushing boats seeing their objective. The 
central observer would moreover see which boats were not receiving 
proper attention and turn at least one battery on any boat near which 
he saw no shell falling. Attacks differ greatly, the above is founded 
on an actual attack made. 
Fewer guns In this case there are perhaps plenty of guns but not 
needed if guns sufficient electric lights available to beat off a well 
and electric planned combined attack of four or five boats with 
lights are high an y certainty, yet with a different siting of fewer 
guns and the same lights such an attack would have 
little chance of success. Thus as in Fig. II, A and E batteries might 
be thrown back on to heights to see over the rays. B could even be dis- 
