France and Belgium 1917. Vol II. Messines and Third Ypres (Passchendaele). OFFICIAL HISTORY OF THE GREAT WAR.

Messines opened on the morning of 7 June 1917 with the tremendous explosion of nineteen mines, nearly one million pounds of explosive. It was the preliminary to Third Ypres which began on 31 July and finally came to a halt on November 10th in the appalling conditions forever associated with the name Passchendaele. The preparation of this volume caused much ill will between Edmonds and Capt G.C. Wynne, one of the team of authors who had been responsible for the first draft. Edmonds redrafted it as he felt Wynne had been too critical of Haig. For his part Wynne requested his name should be withdrawn from any connection with the final version – which came out under Edmonds’s name.