In order to simplify the work, reliefs were, as far as possible, arranged so that battalions always occupied the same sector. The artillery, who had many professional miners in their ranks, made their own dug-outs, with some slight assistance from the R.E. No new work was allowed to be undertaken without the approval of Divisional headquarters; a definite programme could therefore be laid down and adhered to, and, as a result, the minimum of labour was wasted. This system proved highly satisfactory. The Jocks showed a keen interest in the work of trench construction, worked admirably, and took the greatest pride in the result of their labours. An orderly, who was taken on a reconnaissance into the trenches held by a neighbouring Division, summed up the opinion of the Jocks excellently by looking at the narrow trenches with their small sandbagged traverses, and saying, "It's easy seen these trenches belong to some other bodies." So successful in fact was the system, that between 3rd December and 21st March, during which period (with the exception of a three weeks' rest at Achiet le Petit) the Division held this sector, the following work was carried out:-- The front line had been reorganised and the occupied sections made habitable. The support line had been dug throughout its 6000 yards' length, and contained deep dug-outs for its entire garrison. Three main communication trenches had been dug from the Corps line to the front line. The reserve line had been partially completed, and had many dug-outs constructed in it. The Hermies-Doignies-Louverval line had been dug through to make a continuous line. The Hermies-Beaumetz-Morchies line had been dug through to make a continuous line. Many machine-gun emplacements leading from deep dug-outs had also been made, as well as brigade, battalion, and company battle-headquarters. In this area a total of over sixty new dug-outs had been completed. Every trench had been so heavily protected with barbed wire that even the army R.E. park ran dry, and the supply of barbed wire almost ceased. This magnificent record of eight weeks' work, coming at the end of eight months' almost continuous fighting, when the dimensions of the trenches constructed is remembered, clearly proves the value of the system which had been brought into force. General Sir Julian Byng, commanding the Third Army, on visiting the trenches, was so satisfied with the work done that he addressed the following letter to the Divisional commander:-- "The Third Army commander wishes to express to all ranks of the 51st (Highland) Division his keen appreciation of the extremely good work done by the Division in the strengthening of the defences of the line.