182 GARRISON ARTILLERY WARFARE, 
will be fired as rapidly as possible, at the most visible assailant, except 
those which are directed by a P.F. and where the P.F. operator-can 
see. over or through the smoke, when they would be fired by “ P.F. 
predicting.” In the chaos of such an attack, the number of guns that 
can still be directed and fired in this way will have an enormous 
influence in deciding the fortunes of the day, as by so doing, the loss 
of personnel at this stage will be appreciably diminished. At this 
period everything will depend on the nerve and coolness of the 
operator in his ‘cell. He should be shielded therefore from any dis- 
turbing influence, and every resource of skill and cunning should be 
utilised in locating the P.F. The first consideration being where it 
can best exert its influence for the longest possible period during the 
fight, and the next how it can be best concealed from the enemy’s 
view ; to build a little house for it on the flank of a battery, thereby 
making a conspicuous target of it, when near at hand there is a top 
story-room in a house of advantageous frontage that could be hired or 
‘bought for the purpose, is against common sense. If the little house 
exists, it should be left as a decoy, but I should certainly recommend 
the removal of the instrument to the top room aforesaid. In some 
cases, 1t must be in the work itself, if it is to be used. at all. There it 
is naturally out of place, and in its lowest sphere of usefulness, but if 
there is absolutely no other position for it, then it must be concealed 
by every structural expedient. 
Let us now take the case of the D.R.F., the elder brother of the 
-P.F. Owing to the method in which it is worked, it must be situated 
in or close to the work whose guns it ranges. It must have a clear 
‘view of the water area these guns command, consequently the instru- 
ment and operators are exposed to fire, the amount of the exposure 
depending on the visibility of the work and instrument. Ifthe position 
of the D.R.F. can be ascertained by the attackers, it is obviously to 
their advantage to render it unworkable as soon as possible. If the 
see a cluster of heads or an unusual projection on the skyline of the 
work, it will be quite worth their while to devote the fire of a portion 
of their Q.F. guns and Maxims to it. Thus we see that to obtain the 
greatest effect out of either of these instruments, it is absolutely 
necessary that they and their operators should be well concealed from 
-the enemy’s view, which at present is unattainable by the D.R.F., and 
‘consequently it would fail in its purpose as a ranging instrument at 
the most critical stage. 
The same principle of invisibility should influence the site and 
-construction of command posts to enable them to be tenable as long as 
possible. j 
' - As regards communications, the centre whence telephonic messages 
radiate should not be apparent, neither should the receiving ends of 
the radii advertise themselves in any way. Flag signalling in any 
exposed situation will only draw fire. Where facilities exist, failing 
telephonic communication, cyclist orderlies could be very advantage- 
ously employed.’ I am not aware that the pneumatic tube system for 
~ 1 Suggested by another officer. MAF Sorgen es OS & 3 a aac 
