Now if the enemy uses high-explosive shell to take on our batteries he can put them out of action only by registering a direct hit. If the guns are well dug in in good emplacements with head cover it will be possible for high-explosive shell to drop within a dozen yards without doing anything but scare the gunners. Not so, however, with the gas shell. Drop enough gas shell within a dozen or twenty yards of the battery position and the gas will float down with the wind and penetrate every nook and cranny. If the gunners are not quick some of them may be gassed; and if, as is sometimes the case, the gun has been worked short-handed this alone may throw down the rate of fire to a very considerable extent. Add to this the fact that the remainder of the crew will have to don their respirators in order to fight their gun at all, and it can be seen that the rate of fire may be reduced to such a low limit as to make it of little value for the time being; or the gun may even be put out of action completely. Once the first surprise is over and no more immediate killing can be counted on, the bombardment may be continued with persistent gas shell, which are just as effective in making the men wear masks. From our point of view it all comes down to the ability of the gunners to be quick enough at first in preventing themselves from being gassed; and then later of their being capable of carrying on with their firing while wearing masks. It means that gas training and discipline are, if possible, more important for the artillerymen even than for other branches of the service. This is realised to the full in all their training and practice, for if they are not able to respond to an S O S call from the infantry an otherwise abortive German attack may be turned into a disaster. It is like everything else in this war--a question of training and discipline. The neutralisation of the infantry or the transport is conducted on similar lines, and though it rarely reaches the point of being complete a partial neutralisation of reserves which prevents their getting up in sufficient numbers or in time, either for reinforcement or attack, may have most serious consequences in an operation. The partial neutralisation is attempted, just as for the artillery, by killing as many as possible by heavy surprise bombardments with the lethal shell and then continuing with persistent gas in order to force the remainder to wear their gas masks.