THE VALUE OF A HIGH SITE FOR COAST ARTILLERY. 
219 
The causes of A are :— 
Badly adjusted or faulty instrument; defective means for passing 
ranges ; the slipping of a dial; in the absence of an instrument, wrong 
estimation of range ; wrong corrections for tide and travel of objective; 
mistake in group difference or abnormal delay, on the part of Group 
Officer or detachment. 
The causes of B are — 
Incorrect setting of tangent scale or index plate or wrong reading of 
clinometer; neglecting to lay on water line, when using tangent eleva¬ 
tion ; defects in elevating gear or racers ; neglect of Fire Commander to 
compensate for weak powder or atmospheric conditions; irregularity in 
muzzle velocity owing to bad powder, wet sponging or bad ramming 
home. 
IY. Mistakes with Quadrant Elevation. 
A. When the wrong range is given to the guns. 
Under these circumstances the error will be the same, whatever the 
height of site. 
If it is an ‘ under ’ its effect will not be influenced by site : but if it 
is an ‘ over ’ a shot that would hit from the level, might be a miss 
from the high site, on account of the greater value of the angle of 
arrival. 
This defect, however, would be minimised if the objective approached 
to a horizontal target. 
From this we deduce that quadrant elevation should not be used 
from a high site, unless an accurate range finder is installed, that group 
differences should be carefully evaluated, and that the fire commander’s 
corrections for speed and direction are of more moment than on the 
level. 
On the other hand the correction for tide is of more importance, 
the shorter the range and the lower the site. 
B. When the gun is fired at the wrong elevation. 
The causes classed under B all result in a mistake being made of a 
certain number of minutes of elevation. The question then is, which 
site is most affected by the same mistake. 
In order to investigate this question, Table Y. has been compiled, a 
specimen new and old type gun, being taken. 
