The trenches--for the defences could not be called a trench system--consisted of a front line and portions of a support line sited for the most part so that it could not perform the functions for which it was designed. About 2000 yards in rear lay some reserve line posts. The trenches were, in fact, merely those in which men had dug themselves in in front of the Hindenburg Line when following the retreating Germans in their withdrawal in the spring of 1917. With no prospect of the enemy attacking in this sector, they had provided reasonable summer accommodation for their garrisons; at this moment, however, it was not only winter, but it was also morally certain that the Germans were preparing for a spring offensive. The trenches were therefore wholly unsuitable both in construction and siting for the purpose for which they were now required. Indeed, they were little more than a few "Bairnsfather" villas, connected by short lengths of narrow crumbling ditches, which, partly owing to the rank growth of thistles and other weeds, and partly to their siting, had practically no field of fire. It can therefore be said that the Division was given an area 6000 yards in breadth in which to construct a defensive system _de novo_. The front line crossed three spurs and two valleys all running in a north-easterly direction from the main feature of the position, the ridge running from Hermies to Lebucquière. The country was similar in nature to the upland country of the Cambrai battle, and was similarly completely dominated by Bourlon Wood. One was even in view of Bourlon Wood at the Divisional race meetings. The enemy occupied the Hindenburg Line some 2500 yards from the British front line with outposts in an uncompleted line some 300 to 700 yards in advance of it. It was a comfortable sector, the unpleasantness attendant on being in close contact with the enemy, such as mining, trench-mortars, rifle grenades, sniping, and indirect machine-gun fire, being absent. As a rule, the German gunners, in spite of their magnificent observation of our lines, remained inactive. In view of the fact that so much new work was necessary in the sector, General Harper published a memorandum containing certain principles of defence and of trench construction, a document which at their own request was circulated to a number of Divisions, and adopted by them. The chief innovation in this document was the construction of trenches of a far larger size than had been the case in the past. The depth for all trenches was laid down as six feet, their width at the top as eight feet, later increased to nine feet six inches. Each fire-bay was to be fifteen yards in length, with a twenty-three feet traverse separating it from the next one. The minimum breadth of the berm was laid down as three feet. The document ended with the following sentences:--