The medical arrangements were of peculiar difficulty, particularly on the southern part of the front. The two Main Dressing Stations, for stretcher cases and "walking wounded" respectively, were at Forceville, manned by the 108th Field Ambulance, and Clairfaye Farm, further west, manned by the 110th Field Ambulance. The Advanced Dressing Station was situated close to the Albert-Arras Road in Aveluy Wood. Evacuation of wounded from the Regimental Aid Posts in Thiepval Wood and Authuille had to take place over Authuille Bridge, or by the trench tramway which crossed the Ancre to the north of it. The motors of the Field Ambulance were parked on the Martinsart-Albert Road, south of the former village. For "walking wounded" there was a collecting station west of Martinsart, whence horsed wagons carried them by a cross-country track through Hédauville to Clairfaye. From Hamel evacuation was simpler, though even here it had to follow a specially dug trench from the village to a point where the Hamel-Albert Road was screened from observation. On the 22nd and 23rd the infantry took up the positions it was to occupy during the bombardment; the 9th Inniskillings in the right section of Thiepval Wood, the 11th Rifles in the left, and the 9th Irish Fusiliers in the Hamel trenches. These troops had a purgatory to endure. For the most part in the narrow slit assembly trenches, with the rain pouring steadily down upon them, they were under furious German bombardments that wreathed the wood in smoke and flame, and made the crashing of great trees the accompaniment to the roar of bursting shells. On the night of the 26th gas was liberated by us from cylinders in the wood after a great bombardment. It was the first time the Division had had to do with the abominable stuff, which brought no good fortune. Many cylinders were burst by the heavy German barrage, and serious casualties suffered by the men of the Special Brigade responsible for opening the cocks, and by the infantry assisting them.