There was a good example of a concrete dug-out in the right sector at Armentières in September 1916. Some simple-minded soldier, finding that it was gradually filling with water, made a hole through the concrete floor to let the water out. In consequence the dug-out filled with water up to the level of the ground surface in a few hours, driving its occupants out. A battalion medical officer subsequently visiting the trenches came across this dug-out, and thinking it was a storage tank for water, tested the water and caused a notice-board to be placed on it, saying, "For ablution purposes only; not fit for drinking." Breastwork parapets, even when they are not subjected to bombardment, require constant attention. They have in particular a disconcerting habit of settling down and losing height, particularly after rain. In consequence it sometimes happens that by the gradual subsidence of the parapet men may unwittingly expose themselves to enemy snipers in places where a day or two previously they were completely hidden from view. Apart from the amount of labour the upkeep of breastworks requires, there are other reasons which make them unpleasant to live in on an active front. During a bombardment, for instance, when a shell hits the trench, men are constantly being buried in a heap of sandbags and earth. They have then to be dug out immediately to save them from suffocation. In these circumstances the rescue parties often have to work while the bombardment continues, and with enemy snipers and machine-gunners ready to engage them whenever they expose themselves in the breach. German machine-gunners were also expert at firing a series of bursts into a particular portion of breastwork until it became non-bullet-proof. They would then continue firing bursts at irregular intervals at the same spot, with the result that the bullets penetrated the parapet and came through into the trench. Casualties were often caused in this manner. The Highland Division, thus having arrived in France with its training only partially completed, was called upon to undertake a difficult and unpleasant task--namely, the holding and consolidation of a newly-captured position in Flanders. Moreover, the circumstances were such that the Division could not carry out a period of attachment in the line to an experienced Division for instruction. Thus no opportunity was vouchsafed to officers and men of being "put wise" before the full responsibility of holding a captured position was thrust upon them. The significance of this statement is that troops on the first occasion that they enter the battle zone are liable to be "gobrowed" by their new circumstances. They require, as it were, a chaperon to assist them to assess things at their true value, and teach them what not to fear but to respect, and what they may disregard.