Enemy active in morning. At noon I go up to O.P.’s to observe the fire of our 9.2” on Prinz Arnolf Graben and other objects. The enemy retaliated with the most terrible hell of a bombardment. We had to take cover not before we had made good observations. I called on P.P.s Regtl. Sergt. M. and rec’d a copy of Regtl. Order containing my “Mentioned in Dispatches”.
*Prinz Arnolf Graben was a German tunnel, one of many dug by both sides at Vimy Ridge.
*O.P. Trees ~ Built using steel and wrought iron, these are no normal trees. They are camouflaged weapons of war used to devastating effect during World War I on the Western Front. The bizarre fake tree observation posts were built to spy on the enemy after switching them under cover of darkness with real battle-scarred stumps left in no-man’s land. The ideal tree was dead and often it was bomb blasted. The photographs and sketches were then sent to a workshop where artists constructed an artificial tree of hollow steel cylinders. It contained an internal scaffolding for reinforcement, to allow a sniper or observer to ascend within the structure. Then, under the cover of night, the team cut down the authentic tree and dug a hole in the place of its roots, in which they placed the O.P. Tree.