Those cylinders were arranged so that they could all be opened simultaneously by an electrical device. This was a marked improvement on the old system, in which each cylinder required four men to carry it up to the front line, and then had to be left in position until a wind of the right velocity was blowing in the required direction, in danger of being burst by shell-fire and flooding our own trenches with gas. In the case of the “gas beam” the train was not moved up to the position of discharge until the wind was suitable, so that the gas could be released immediately on arrival, and was thus stored in the trench area for the shortest possible time.
Prior to the discharge the front and support lines in the area liable to be affected by the gas were evacuated by their garrisons. The train carrying the cylinders was then moved into position without incident. A machine-gun bullet penetrated one of the cylinders, but the escape of gas was quickly stopped by the presence of mind of one of the gas personnel, who plugged the holes made in the cylinder with clay.
The discharge then took place, and as far as could be seen the “gas beam” rolled slowly over to the German lines, the wind at the time having dropped to about four miles an hour.
In the morning the Flying Corps observers reported that a broad belt of discoloured grass showed that the beam had travelled some 4000-5000 yards into the enemy’s country towards Douai. What effect it had on the Germans is not known. No kind of alarms seem to have been given from the German front-line trenches. The German batteries in the area affected by the gas were, however, silent for several days.
When the troops returned to the front and support lines after the discharge, they found numbers of rats, moles, and beetles dead at the bottom of the trenches, while the brass shell-cases hung up as gas-gongs were coated with a deposit of verdigris about the depth of a half-crown piece, evident signs that the gas was a fairly powerful mixture.
During this period General Carter-Campbell had a heavy task to perform. Not only had a new system of defence to be planned and put into effect, but the Division itself required time and opportunity to recuperate. As the official despatch says: “All battalions were urgently in need of rest, and contained large numbers of young, partially trained, and wholly inexperienced recruits, and subordinate commanders had had little or no opportunity of becoming acquainted with their men.”
To meet this contingency intensive training was carried out by the brigade and the battalions resting, in so far as the demands made upon them for working parties would allow. Divisional classes were formed, and every effort was made by commanders to turn their battalions into trained units in the shortest possible time.
The inexperience on the part of the men, and the successful way in which it was eliminated, is well illustrated by their efforts on patrol. Six to eight patrols were out in No Man’s Land covering the Divisional front every night, but these were at first almost ineffective; not only did they hesitate to engage enemy patrols and were inclined to avoid them, but they allowed themselves to be outwitted by them. By 26th May the Division had lost one officer and three men missing without a single prisoner having been captured.
On 26th May an enemy patrol reached our lines, bombed a post, and wounded two men. This date was, however, the turning-point; the next night a similar attempt was made, but was defeated. The following night a sergeant of the 100th Grenadiers was captured, on 9th June a second N.C.O. was captured, and on the 12th a private. Finally, on 14th June, a patrol of one officer and four other ranks of the 6th Seaforth Highlanders waylaid an enemy patrol of seven men and captured it complete.
By the end of the tour in this sector, the men had become really good on patrol, completely dominated No Man’s Land, and would immediately attack and disperse any patrol they encountered.