2 
of all the advantages which the defenders may derive from a repeating rifle with 
smokeless powder, the assailants may easily drive out their adversaries if they 
make extensive use of the plunging fire of shrapnel shell. 
To prove his statement, General von Sauer begins by remarking that direct 
fire has two serious inconveniences. First, the small angle of descent of the 
projectiles, which prevents troops, sheltered even by a low parapet, from being 
struck ; secondly, the low angle of elevation, which prevents the piece from being 
fired “from a position concealed from the view of the enemy.” 
It may be remarked at once that these statements are too sweeping; certain 
restrictions must be made, which are important, and on which something should 
be said. For instance, with regard to the angles of descent, it is well known 
that at long ranges they are so considerable that the projectiles can strike a 
target placed behind a parapet. Thus, at 5000 metres the shell of the 9 C Ger¬ 
man field gun lias an angle of descent of 31°. At 3500 metres the angle of 
descent of the 9 c shrapnel is 16°, and, the angle of the cone of dispersion being 
from 20° to 22°, it follows that the bullets placed at the lower part of this cone 
will strike the ground at an angle of 26° to 27°. It is only at medium and 
short ranges that plunging fire has in this respect a real superiority over direct; 
and even when a target cannot be reached by direct frontal fire, it can often be 
struck by oblique fire without having recourse to plunging fire. 
Again, with regard to firing from behind a covering mass, indirect field firing 
may be carried on under these very conditions. It is true that the pieces must 
be withdrawn some distance from the covering crest to enable the projectiles to 
pass over it, so that the protection is only relative; but they are completely 
covered from the view of the enemy, which is very important, especially when 
smokeless powder is used. The existence of a covering mass in front of the 
guns is a serious difficulty in the regulation of the enemy’s fire. As an artillery 
officer, General von Sauer cannot be ignorant of this truth. The minimum 
distance which must exist between the pieces and the covering crest in the case 
of direct and indirect fire depends upon the height of this crest above the 
horizontal plane passing through the axis of the trunnions, and upon the angle 
of elevation of fire. It may be useful to give some statistics for purposes of 
comparison. 
We have assumed the case of a German 9 c Field Battery placed behind a 
covering mass of three metres in height, such as a railway embankment, and 
firing shrapnel shell. The following table gives, for every 500 yards of range, 
the minimum distance at which the battery must be placed behind the covering 
crest in order to carry on its fire :— 
Range. 
Elevation. 
Distance between the 
Battery and the 
covering crest. 
*1000™ 
= 1083y ds 
1° 4' 
80 ra = 87y ds 
1500 
= 1625 
3° 4' 
44 = 48 
2000 
= 2167 
4° 34' 
29 = 31 
2500 
= 2708 
6° 22' 
21 = 23 
3000 
= 3250 
8° 19' 
16 = 17 
3500 
= 3792 
10° 34' 
13 = 14 
These distances, it will be seen, are not excessive ; and the Battery Commander 
might easily place himself near the covering crest so as to see the target, and 
direct the fire of his guns in person. A battery for high-angle fire, with higher 
angles of elevation, can, of course, if the ground permits, be placed closer to the 
covering mass, but it will be seen presently that this advantage is often illusory 
in the field. 
1 A French metre being equal to 39 inches very nearly.— J.H. G,B. 
