On it were a large quarry and two woods, named Hausa and Delbar, which commanded extensive views, observation posts in the tree-tops covering a vast expanse of the surrounding country. The whole feature formed an extensive and lofty plateau, which stretched almost to the Scarpe, the ground falling down to the water’s edge in a steep slope. This slope, being covered with trees, afforded the enemy a good covered approach along the banks of the river.
The position as it stood was one which could not be allowed to remain. A successful attack from the Germans would force our troops into the Scarpe. Moreover, there was little room in the confined area between the front line and the river in which to manœuvre troops to resist attack.
On the other hand, if a force moving over Greenland Hill and north of it could strike at Plouvain, the Germans between Plouvain and the chemical works would find it almost impossible to extricate themselves.
Orders were therefore issued for an attack to be prepared with this intention.
In the circumstances, one of the earliest considerations was the gaining of ground by minor enterprises, so as to extend the area in which troops could be assembled for the attack.
[Map V].—The Chemical Works, Roeux.
On 18th April the front line was extended southwards by the occupation of a portion of sunken road running parallel with the Scarpe about 300 yards east of it.
At 3 P.M. on the 21st the 9th Royal Scots carried out an operation with a view to extending our hold on this road farther southwards. This attack was at first successful, but subsequently a local counter-attack on the right restored the situation for the enemy. The net result was, however, that one additional post was established 150 yards in advance of the sunken road.