The holding of a new-won position after a great attack was always an unpleasant task. In this case the conditions were, from some points of view, more difficult than those of the capture of the ridge. "Jerry was angry," said the men, with justice. The Germans now had a mass of heavy artillery behind the Canal d'Ypres, and day and night they shelled the British forward positions and the western slope of the ridge. On their second day in the line the Headquarters of the 109th Brigade in the Grand Bois were so heavily bombarded that General Nugent decided they should be withdrawn to a company headquarters in our old lines. The troops in the front trenches were on a forward slope, very exposed to observation, and suffered heavily. At night ration parties on the roads had many evil experiences. Casualties rarely amounted to less than a hundred for the period of twenty-four hours, and several battalions had considerably greater losses in ten days of this experience than in the period from the 7th to the 9th of June. Nor was it alone upon areas over which he had observation from the ground that the enemy was able to bring to bear accurate fire. Parties on railway work, lorries on the Wytschaete Road, suffered very heavily also. The reason was that the situation in the air had altered. British supremacy there had been absolute. Not a German aeroplane had been seen during the battle. Since then certain of our squadrons had moved north to the Salient. The German air force, on the contrary, had been heavily reinforced. In particular the famous Richthofen, with a squadron of very fast single-seater scouts, painted bright red, raged up and down the front, catching many of our comparatively slow photographic and artillery aeroplanes, and shooting them down. Another favourite device of his was to sweep low over our trenches, firing belt after belt upon the infantry in them, who retorted, without much effect, by the fire of machine-guns on anti-aircraft mountings. But his most spectacular feat was undoubtedly the burning of our balloons. Of these there was a great number on the front. From Kemmel about fourteen could be counted, stretching almost to the coast on one side, and perhaps to Estaires on the other. For men in the neighbourhood of the hill it became one of the interests of those sunny afternoons to watch the balloons. The programme was always of a similar nature. There would be a sudden uproar of anti-aircraft fire, a fast-moving dot would approach one of the balloons, two silver dots below the latter would represent the observers making their way earthwards in their parachutes. A tiny flicker of fire would appear atop of the balloon, swiftly growing and spreading. Within a few seconds the flaming mass would sink slowly. Sometimes the aggressor would dart straight off to the next balloon in the line, and repeat the process with that. On the afternoon of June the 23rd, three balloons in succession were brought down by one aeroplane.