(4) Machine gunners, artillery observers and when possible all officers in the front line will be issued with oxygen breathing apparatus (Selbstretter). It is desirable that men who are used to working with the apparatus in peace time should be detailed to assist artillery observers and machine gunners in the use of the apparatus, to enable the latter to carry out their particular duties undisturbed. Special stress is laid on the necessity for affording every possible protection to the machine gunners and artillery observers. (5) The Pulmotors and large oxygen apparatus must be kept in readiness at suitable points behind the front--the situation of all this apparatus should be known to the troops. (6) As soon as the weather conditions favor a hostile gas attack, all commanders must exercise the utmost vigilance. All the above mentioned protective appliances will be once more inspected as regards numbers and conditions. In particular all preparations should be completed so that, the moment a gas cloud appears, fire may be opened by artillery, infantry, machine guns, minenwerfer and hand grenades. At the same time care should be taken that equanimity of troops is not disturbed by all these preparations. (7) At the first sure sign of an impending gas attack a signal will be given for donning respirators and opening fire. It is specially desirable to direct enfilade fire on the area covered by the gas. (8) It is a mistake, before or at the beginning of a gas attack, to leave only a weak garrison in the front trenches and withdraw the remainder of the troops into the support trenches, as the effect of the gas will be equally felt in these. It is almost equally mistaken, to allow the men to withdraw laterally along the front trench. It is imperatively necessary that every man should remain in his place and commence firing. INSTRUCTIONS FOR TRAINING IN COMBATING HOSTILE GAS ATTACKS (1) _Training to be directed by Officers._ (1) Instructions as to the harmless nature of a gas attack if a timely and correct use be made of the respirators, and if a combined fire of all arms be directed against the gas cloud. (2) Drill in putting on the respirators, fire being opened immediately afterward. (3) Respirators to be worn while firing. (4) Instructions regarding wind and weather conditions which favor or prevent a hostile gas attack. (2) _Training to be given by Medical Officers._ (1) The use of the respirator. (2) The rapid improvisation of a substitute in case the respirator has been lost or become unserviceable. (3) Training of Officers, Artillery Observers, Machine Gunners, and a number of other suitable men in the manipulation of the oxygen breathing apparatus. Special stress is to be laid in the training of Artillery Observers.