Chapter 9

Tunnels and the Infantry Attack

As well as being a means of placing explosives beneath the enemy, mining could also potentially provide a concealed and protected means of attacking troops crossing no man’s land. In pre-war practice, saps dug towards the enemy positions during a siege might need to be covered or ‘blinded’ by a covering of timber and earth. Where the soil allowed it, the sap might be dug forward wholly underground, at a depth of 25 or 30cm, without timber support. In the French Army these were known as ‘sape russe’ and the name was adopted by the British as the Russian sap. The saps were shallow enough for the top cover to be quickly broken down so that it could be used as a communication trench.¹

In the spring and summer of 1915, the French used Russian saps as a means of getting close to the German positions undetected. After the capture of Carency and Neuville St Vaast during the Second Battle of Artois in May 1915, a third attack was made by the French on 25 September 1915 in combination with their attack at Champagne and the British attack at Loos. An attack on the forward slope of Vimy Ridge was to be the Third Battle of Artois. In front of Neuville St Vaast, French attempts to take German positions at Hill 123 and the Cinq-Chemins, where the German front line occupied a sunken road (adjacent to the route of the present A26), had failed. The 3rd Corps commander, General Hache, proposed in August ‘a new and very special process’ involving attack using sapping above and below ground.² The problem, as identified by Hache, was that if the French succeeded in capturing the sunken lane, the Germans would still be able to launch counterattacks from the rear and flanks owing to the large number of communication trenches to the position. They would cut off the French using an artillery barrage on the captured ground and through lack of their own communication trenches to the sunken lane the French would not be able to reinforce them. The novelty of Hache’s scheme lay in the wide front in which the sapping attack was applied and the large number of saps which he proposed to dig. The proposal called for a sap about every 40m, or seventy saps on the whole front of the 3rd Corps. The attack was to be made in a ‘sure and methodical way’. First a starting parallel was to be pushed to within 50m of the sunken road and then a large number of Russian saps were to be pushed forward to within a few metres of the sunken lane, which troops could capture with grenades. The multiple saps would then provide the means of maintaining supply to the captured position across the German artillery barrage. The rate of advance was to be initially 10m per 24 hours, increasing to 15m. Therefore fifteen to twenty days would be required to prepare for the attack.