The Battle of Messines was over by June 12, but it was considered that if an attack in the strongly fortified Ypres Salient was to have a real chance of success, it must be an attack in force, a regular full-dress battle, for which the preparations were then held to be necessarily extremely elaborate. About six weeks were therefore to elapse before the attack was launched. Once launched, however, the attackers must gain their objectives rapidly. That was essential to the plan. The Russian front was crumbling. Germany was bringing troops and guns westward. We should soon be face to face with an enemy so strongly reinforced that our chance of victory in an attack would be slight. [28]“It was in some degree a race against time. If a true strategic purpose was to be effected before winter, the first stages must be quickly passed. The high ground east of the Salient must be won in a fortnight, to enable the British to move against the German bases in West Flanders and clear the coastline.” Not only must we hasten because we faced an enemy whose strength would be increasing daily, but because we were to attack in Flanders, and the summer would be far spent before we could complete our preparations. The enemy’s lines lay on the slopes of the semicircle of low hills that overlook Ypres. Behind him lay another swampy valley, which rose again to another slightly higher crescent of hills. In the inner arena lay the ruins of Ypres, and, set in the marshy levels and immediately overlooked by the first semicircle of hillocks and more distantly by the second, lay our lines. [29]“The territory lying within the crescent was practically all reclaimed swamp land including Ypres and as far back as to St. Omer, both of which, a few hundred years ago, were seaports. All agriculture in this area depended on careful drainage, the water being carried away in innumerable dykes. So important was the maintenance of this drainage system considered, that in normal times a Belgian farmer who allowed his dykes to fall into disrepair was heavily fined.” Across this terrain two great armies had faced each other for nearly three years. The Salient was, after Verdun, the most tortured of the Western battlefields. Constant shelling of the low ground west of the ridges had blocked or diverted the streams and the natural drainage, and turned it into a sodden wilderness. If August was a wet month, as it had been the year before for the Battle of the Somme, our chance of success was scanty. [30]“Much rain would make a morass of the Salient where Tanks could not be used, transport could scarcely move, and troops would be exposed to the last degree of misery.” However, the previous shelling of the ground was as nothing compared with the bombardment which we now intended to inflict. Every corner of the enemy’s ground was to be drenched with our fire.