It is advisable, when time and means permit, to operate these small railways of 40-centimetre gauge in the trenches themselves, when they are sufficiently wide for the purpose. The small trucks, pushed by men, will bring the torpedoes and other munitions as far as possible, but when the narrowness of the excavations prevents this, supplies must be carried by hand to the most advanced lines. This work, which is very laborious, should be left, whenever possible, to men drawn from regiments in the rear which are not intended to take part in the impending attack. For the last year North African burros have been used for carrying the munitions through the communication trenches. They are hardy animals, easy to drive, and they save the troops a great deal of labour.
4. Importance of the munition supply. To give our readers an idea of the enormous work involved in munition transportation, we append some figures obtained from a field battery operating in the first lines on the Aisne in March and April, 1917.
On the 12th of April the reserve in munitions of that four-gun battery was 2000 shells per gun; i. e., 8000. From the 15th onward the battery received 1500 shells daily. On the 19th, in the evening, there remained only 1700 shells. The battery had therefore fired from the 12th to the 19th about 3600 shells per gun. This is a normal figure, and explains why millions of shells are fired on a large front in a few hours.
Precautions. The enormous quantity of projectiles and supplies of all kinds in the different parks prevents them from being sheltered or even concealed, and, in order to limit the accidents caused by explosions, the stacks of ammunition are far from one another. In an effort to hide them from the enemy aviation, painted cloths, or green or brown coloured grasses, are thrown over them, so as to deceive the eye.
For some reason or other the aviation of the enemy has not caused very great damage to our various ammunition stores. The damage, as a rule, has been confined to the explosion of the stacks directly hit, although, at the beginning of the operations on the Somme, a German aviator succeeded in destroying completely in the rear of the English lines a large park of all sorts and sizes of shells.
The Allies also have often caused the explosion of German munition depots, but the damage done, to all appearances, has always been limited.
5. Replacing the guns. We have just seen that some field guns fire as many as 3600 shots in a few days. This, added to the rapidity of the firing (at times fifteen shots a minute, during barrages), explains the rapid wear of the guns, whose metal becomes decomposed by the heat.
In spite of the quality of the steel, the guns wear out and finally burst. It is of the utmost importance to replace those put out of service by wear, or by the fire of the enemy.
This duty rests with the Divisional Park, which must have a reserve sufficient for all needs. The park must also be prepared to repair all the guns which are not so badly injured as to require shipment back to the Army Park.
The battery to whose consumption of munitions we have previously referred had, from the 12th to the 19th of April, to make the following changes: