During the third battle of Ypres in Westhoek, Belgium on 31st July 1917 when his command was held up in attack owing to heavy machine-gun fire, Brigadier-General Coffin went forward and made an inspection of his front posts. Although under the heaviest of fire from both machine-guns and rifles and in full view of the enemy, he showed an utter disregard of personal danger, walking quietly from shell-hole to shell-hole, giving advice and cheering his men by his presence. His gallant conduct had the greatest effect on all ranks and it was largely owing to his personal courage and example that the shell-hole line was held.