MOUNTINGS FOR COAST ARTILLERY. 547' 
vision of an auto-sight is of the greatest importance. Working by 
range-finder involves the following operations ;— 
1. —Laying of telescope. 
2. —Eeading of range. 
3. —Transmission of range to gun. 
4. —Putting elevation on sight. 
5. —Laying gun. 
There are thus practically five possible sources of error, any one of 
which may suffice to throw away a round. 1 In deliberate peace practice, 
these errors may rarely occur; but, at a time of excitement it is highly 
probable that some of them will supervene. An auto-sight eliminates 
four of these sources of error, and must materially improve the speed 
of fire; The gun-layer replaces the R.F. operator and, subject to due 
correction for “ error of the day,” a single operation accurately per¬ 
formed suffices. This is only one aspect of the question. In the case 
of a target moving at speed, these successive operations evidently can¬ 
not be performed, and the auto-sight stands above all possible com¬ 
petition. The full value of the auto-sight, when used against a moving 
target, can, however, only be obtained on three conditions, viz.:— 
(a.) The gun-layer must be enabled to control the gun, or, in 
other words, to do his own fine laying. 
(b.) The gun-layer should be able to fire with his eye along the 
line of sight. 
(c.) It should be possible to use a telescope. 
These conditions can be satisfactorily fulfilled only by a non-recoiling 
sight. Early in January 1896, therefore, I proposed a carriage auto¬ 
sight, which I have since fully worked out for 9*2-in. B.L., and for 6-in., 
4-7-in., 12-pr. and 6-pr. Q.F .guns. All these sights are under manufac¬ 
ture, and extensive trials have already been made with the 12-pr. 2 This 
auto-sight is either of simple or combined type. In the latter 
case, by a turn of a lever, the sight becomes the ordinary bar and 
drum arrangement. It is, therefore, possible to lay on the water-line 
of a ship with the auto-sight, unlatch and lay on the deck or tops, the 
proper elevation being automatically put on by the first operation. 
Means of correction for tide and for error of the day are provided, and 
in the case of the 4*7-in., 6-in. and 9*2-in. sights there is a telescope 
in addition to the V, so that either can be used at pleasure. 
Prophecy is usually disastrous; but I may express the hope that this 
auto-sight will alike simplify and greatly accelerate the service of coast 
artillery. Much will, however, necessarily depend upon what may be 
termed policy. The idea of subjecting a large number of guns to the 
control of a single individual ensconced in a cell on a neighbouring hill¬ 
top possesses many theoretical attractions. In practice, the necessary 
1 In some P.F. installations the sources of error are even more numerous and in action mis¬ 
understandings and delay appear inevitable. 
2 The conditions at Shoeburyness—a height of 25 ft. obtained by building up a platform of 
timber which was far from rigid—were unfavourable ; but up to 1100 yards the shooting was 
extremely good. On the other hand, the sight had the advantage of being used by an excellent 
gun-layer. 
