Ammunition Supply. Before the war all armies were
equipped with mobile ammunition columns, which served the
needs both of infantry and machine-guns and of the artillery
itself. As a rule certain columns in each formation were sup-
plied with limbered vehicles and field artillery horses, and were
as mobile as the batteries, while the remainder, with vehicles
of the ordinary army type, possessed the mobility of baggage
columns only. In Great Britain a considerable advance toward
simplifying the ammunition supply service had been made by
introducing lorry transport, worked on the same system as that
which provided the army's daily bread, and by attaching a light
ammunition column permanently to every brigade of field
artillery. But when trench warfare set in, and all supply at the
front was based on a system of " dumps," the mobile reserve
of ammunition constituted by these brigade ammunition
columns was not required. They were therefore put back into
the " divisional " ammunition column, or second echelon of
supply, which itself was recast on a much smaller scale. 1 In
the more open warfare of 1918, however, it was found necessary
to return a portion of them to divisional control.
The batteries themselves retained, and necessarily so, all their original wagons.
The organization, and nature of transport, required for re- serve ammunition in the future depends principally on the organization and motive power of the batteries. But it may be assumed with some confidence that since mechanical transport improves every year in available numbers, trustworthiness in different conditions, and freedom of movement, horsed am- munition columns are a thing of the past. Even theatres of war for which mechanical transport is unsuitable to-day will be open to it to-morrow.
Organization of Artillery Motors. During the war the per- sonnel in charge of the artillery motor lorries, tractors, and other motor vehicles were not artillerymen, but were taken from the transport services. This was only a provisional arrangement, due to the fact that the artillerymen were not competent to take charge of motor vehicles. As the motor replaces the artillery horse, this incongruity will naturally disappear, and the artillery will drive their own motors. This will presumably not apply to lorries used to transport guns behind the fighting line, as de- scribed above, since these lorries will be general transport, available for other troops when not employed with the artillery. The leading principle is that all men who go into action with the guns, or who are available to replace casualties in the fighting line, must be artillerymen.
Special Artillery and Scientific Auxiliaries. The introduction of guns of accompaniment, to advance with the front line of the infantry, is contemplated in all armies. The question arises whether these guns are to belong to the infantry, like their own machine-guns, or to the artillery. It is urged on the one hand that the special knowledge required to use a field gun is such as the infantry cannot be expected to attain. On the other hand, infantry officers point out that the gun is not required for general artillery purposes, but merely as a large-bore machine-gun, and that the detachment must be thoroughly familiar with infantry work. The decision between these two views seems to depend on whether the guns of accompaniment are to be used as bat- teries or as single guns. In the latter case, they should be infantry, not artillery, weapons.
A more difficult question is whether tanks armed with guns are to belong to the artillery or to a separate tank corps. It is easy to draw the line between a fighting tank which has a gun as part of its armament, and a tractor which pulls a gun into action and then waits behind like a limber and team. These are the two extremes, but there are intermediate forms, such as the tank which carries a gun on a platform, capable of fighting either on top of the tank or on the ground, and the tank which is an integral part of the gun-mounting, and is technically an automobile gun-carriage. It seems probable that all these types
1 In the new organization, that part of the divisional ammunition column which carried the second reserve of gun ammunition was reduced to one-seventh of its former size.
will belong to the artillery, except the tank proper, in which the gun is only a subsidiary part of the armament.
Finally, it is significant that in reducing the artillery to the minimum imposed by the Peace of Versailles, Germany has chosen to retain both accompanying guns, anti-tank guns and scientific sections (flash-spotting, sound-ranging, meteorological and survey) on the regular establishment of the arm.
(H. A. B.; C. F. A.)
VI. THE EFFECT or ARTILLERY PROJECTILES
It is of great importance to the soldier to know the probable effect of artillery projectiles. On the one hand, the artillery commander must know what nature of projectile to use for a given task, and how many will have to be fired, and, on the other, the troops must know what measures to adopt in order to escape the shell-effect, or to minimize it.
The projectiles fired by land artillery are shrapnel shell, H.E. shell, and chemical, incendiary and illuminating shell. They may also have to fire armour-piercing shell at armoured forts and at tanks, though these shell are not part of their usual equipment.
Shrapnel Shell. This is the most efficient man-killing projectile against troops exposed in the open or when manning a parapet. The French calculate that in 1914, when their artillery fired little but shrapnel, they killed five men of the enemy for every ton of ammu- nition expended, whereas in 1918, when, after a long period of trench warfare, the proportion was only 5 % of field artillery shrapnel to 95 % of H. E. shell, they killed only one man per 4 tons of ammuni- tion. The reduction in the proportion of shrapnel carried was due to the difficulty and expense of supply, especially as regards the fuze.
The object of the designer of gun and ammunition, and of the gunner who uses them, is to obtain a dense shower of bullets flying forward close to the ground.
With a view to shrapnel effect, the gun-designer produces a gun with high velocity, long range, and flat trajectory. But a gun equip- ment of given weight can produce only a given amount of shell energy, which is measured by the product of the weight of the shell and the square of its velocity. Consequently there must be a com- promise between a heavy shrapnel and a light high-velocity one. This has been solved differently by different nations, as follows :
Weight
in
Weight
Muzzle
Number
Number of
Action of Gun
of Shrapnel Ib.
Velocity fs.
of Bullets to the Ib.
Bullets in Shrap-
nel.
Russia
21
14?
1.930
43
260
France
23
16
1,740
38
292
Great Britain .
24!
I8J
1,615
41
375
Germany
I8f
'5
1,525
45
300
The Russian and French guns are best adapted for shrapnel fire. The French use a heavy far-reaching bullet, which, in their flat- trajectory gun, gives a deep zone of shrapnel effect, suited to their bold method of opening fire, which is intended to produce a crushing effect on the enemy with the least possible delay. The Germans were obliged by the low power and curved trajectory of their field gun, in which muzzle energy was subordinated to mobility, to abandon the idea of a far-reaching shrapnel and to accept the necessity of expending more rounds for searching a given depth.
Another consideration affecting the question of high velocity versus heavy shell is that the light shell loses its high remaining velocity, which gives the forward impulse to the bullets, much sooner than the heavy shell, so that much of the power of the gun is wasted on overcoming air-resistance, instead of being communicated to the bullets. However, it maintains the initial advantage due to a low angle of elevation up to extreme shrapnel range. The loss of remain- ing velocity can be partly compensated for by increasing the driving charge in the shell. The shrapnel then acts as a short gun fired close to the enemy. But although this expedient is adopted to some extent in most equipments the limit of efficiency is soon reached, since the large charge reduces the bullet capacity of the shell, and the body has to be made with stout walls, or of very high-grade steel, not always available in war-time, to prevent the shrapnel from blowing to pieces instead of acting as a gun.
Weight of Shrapnel Bullets. The weight of the shrapnel bullet, which is necessarily spherical, is of great importance to the effect. Elongated shrapnel bullets are out of the question, since there is no means of imparting rotation to them. AH attempts in that direction have been failures. Of two spherical bullets the heavier will travel further before pitching into the ground, and so will have a longer period of efficiency. The heaviest metal practically available for shrapnel bullets is hardened lead. Tungsten and other heavy metals have been proposed, but are not available in sufficient quantities for