A War for King and Empire: A Malcolm MacPhail WW1 novel (Malcolm MacPhail WW1 series, Band 3)

Early 1915. The most dangerous place on Earth.
Malcolm MacPhail enlisted in the army to fight the Hun and get out of town - not necessarily in that order. Now he's arrived in the infamous Ypres Salient. It's pouring, he's up to his shins in mud and he's had his first terrifying acquaintance with the enemy howitzers. The Great War is proving less glorious than he imagined.
If he's to survive on the deadly front lines of the Western Front Malcolm must become a soldier. However, when a shady acquaintance from home turns up to remind him of his past and looking for trouble, suddenly he faces enemies in front and behind.
Unbeknownst to the Allies the Germans are readying a secret weapon, bent on conquering the Salient. Malcolm and a close-knit band of soldiers are all that stand between them and a devastating victory…
*****
Chronologically the first in the series, followed by Malcolm MacPhail's Great War and My Hundred Days of War.