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THE VALUE OF A HIGH SITE FOR COAST ARTILLERY. 
Let PV' —v and the angle PRV' = (co + /3), then a shot from the 
high site would have to have a longitudinal error equal to PR, if it 
just missed the objective; thus 
PR=v’ cosec (■»+£)> 
= cl cot co -f- (3 -f- b. 
(Art. II.) 
At the same time, let the trajectory in. fig. 9 be such, that the error 
PT would cause the objective of fig. 10 to be just missed from the low 
site also; then 
PT—v cosec co, 
= a cot (o + b, 
PX= (a cot a, + b). 
sm(co + /3) v ' 
Now PX is < PR, if 
(Art. II.) 
or if 
. Sm ** . , (a cot (o + b) isCacot (co+/3) + 6, 
sma)+/3 v v ’ 
a cos © + b sin co is<acos (eo+/3) + & sin(a> + /3), 
or if 
sin(a) + X) is < sin (&> + /3+X), 
where X has the same value as in Art. II. 
Now in all practical cases we know this result must be true, as, of 
necessity, (co + /3 + X) must be less than 90°, hence even in the most 
favourable circumstances as regards objective, the low site will always 
be at a disadvantage, which increases as the objective approaches a 
horizontal target. 
In the case of ‘ unders ’ the advantage reaped by the high site is 
relatively even greater, for it benefits from the fact that PX is always ( 
less than PT, without being affected by the ratio cot 8 : cot co. 
VI. The Advantage of the High Site. 
We have seen that not only is the accuracy of the weapon increased, 
the higher the site upon which it is placed, but also the mistakes, 
accidents &c. that may occur in its working, have less effect on it, for 
the advantage that the low site possesses, under certain circumstances, 
when using quadrant elevation, may be neglected in the discussion, as 
quadrant elevation on the level is, as far as the trajectory is concerned, 
the same as tangent elevation, and the advantages of the high site 
when this means of elevation is used, are great and incontestable. In 
addition the mistakes classed as A should not occur ; some of those under 
B are unpreventable, but as regards these, the high site is in a better 
position than the low, whatever kind of elevation is used. 
