THE EOYAL ARTILLERY INSTITUTION. 
387 
(3) On the defensive, the battery commander should select as a position for 
his guns a spot from which all communications open to an enemy can be well 
commanded by the fire of the battery; he should endeavour at the same time to 
avail himself of every existing natural cover, or, when time admits, to get his 
battery under cover artificially; the distances of remarkable points of the ground 
in front—particularly of such parts as are calculated to delay the march of an 
enemy through difficulties of the ground—are measured by pacing. When the 
ground is favourable and permits of accurate observation of practice, and when the 
enemy is formed in large detachments, fire with common shell may be opened at 
2000 or even 2500 yards, on the defensive. 
When the enemy advances to a distance of from 850 to 1100 yards, shrapnel shells 
should be fired against columns; against detachments of small depth common shells 
should be fired at a high or low angle, according to circumstances. The rate of 
fire should correspond with the range, but under 250 yards an enemy should be 
plied with case shot as fast as possible. If our own troops retreat, the battery 
should be brought back to a position several hundred yards to the rear: that 
position should be particularly selected as one admitting of being long held and of 
a continuous fire. In such changes of position, the question as to whether the 
guns should be laden on the mules or not, must be decided by the style of engage¬ 
ment and the nature of the ground; generally speaking, the guns should be taken 
back by hand. 
(4) In mountain warfare, engagements take place chiefly in and about defiles, 
and about heights. 
The tactical importance of a defile depends on the strength of the troops who 
wish to pass it, on the style of engagement, on the nature of the ground in front 
or in rear of the defile, and on the dimensions of the defile. 
In general the defence of a defile is undertaken from the rear: rarely from the 
front or from the inside. 
A defensive position is taken up in front of a defile when in the act of retreating 
or when the nature of the ground is such as to present unusual advantages. In 
such case the guns should take post on the flank of the mouth of the defile, so as 
to be able to fire on the approaches and places of assembly of the enemy, and to 
ply the ground immediately in front with case shot. The guns, if possible, should 
be under artificial or natural cover, and should open fire as soon as the enemy 
comes within range. If our own troops are retreating, the battery should perse- 
veringly continue firing as fast as possible until the troops have passed the defile; 
it should then retreat and take up a position some 800 yards in rear of the defile 
to prevent the enemy from debouching, at any rate to delay his opening fire as 
long as possible. 
In the attack of an enemy in a defensive position in front of a defile the guns 
should be placed in position short of the most effective range, one part in the 
prolongation of the defile and the other to the flank, thus bringing the enemy under 
a cross-fire. The attacking guns direct their fire at the mouth of the defile, 
enfilading it; while those to the flank engage the guns posted in defence. 
High-angle fire of common shells against the inside of the defile and against the 
enemy’s guns, and low-angle fire for enfilading the defile and against the troops 
and guns in the open, will be found most suitable to the occasion. 
The defence of a defile by guns inside it is not usually undertaken, for the retreat 
of the guns is generally involved in difficulty. Should however, such a position 
have been taken up, the guns should be placed behind obstacles to bar the way; 
they should continue their fire until the close approach of the enemy and the pro¬ 
bability of losing the guns compel them to retreat. 
The artillery of the assailant can only rarely be used inside the defile; but when 
so used, its duty is to cannonade the position of the enemy in the defile, as well as 
