Sooner or later in the course of his trench experience the soldier will be subjected to an infantry attack. Artillery shelling, aeroplane attacks, mining, etc., are part of everyday's programme, but infantry attacks come only now and then. They _may_ come at any time and the enemy is not in the habit of announcing them beforehand. It is not likely that they will occur in broad daylight without any warning. If they are to be made then, they will be preceded always by a concentrated artillery preparation. Night is the danger time. There are two periods of special danger--one, the hour before sunrise, and the other the hour after sunset. At these times there is sufficient light for men to be able to see their way to advance over almost any ground, and not sufficient light for the defending force to be able to take careful sight with their rifles and machine guns, etc. Consequently these hours are the most favourable for making an attack, and every one must be on the alert to ward them off. These times are called "Stand tos" or properly "Stand to arms." While they last, every officer and every man of the front and support line is on duty. Rifles are cleaned, inspected and loaded, bombs, gas-masks, revolvers, bayonets, etc., are got ready, and every one remains at his post of duty. In the blackness of night and in the broad light of day the danger is much less and consequently some of the force can be relieved for other tasks, during the night, or for rest during the day. Should an attack be made, it becomes the business of the men in the trench to hold the enemy off just as long as they can, at whatever cost to themselves, while some one telegraphs back for the supports and reserves, and possibly for the assistance of the artillery. Trenches must never be surrendered without giving these fresh men a chance to regain the advantage, and should the trench be lost, a counter attack must be immediately arranged before the enemy has had time to reverse the trenches and connect them up by saps and communicating trenches with his own system. No time must be lost, for the longer the delay, the greater the difficulty of making the counter attack successful.