To be in the trenches was to experience an unreal, unforgettable enclosure and constraint, as well as a sense of being unoriented and lost. One saw two things only: the walls of an unlocalized, undifferentiated earth and the sky above. Fourteen years after the war J. R. Ackerley was wandering through an unfrequented part of a town in India. "The streets became narrower and narrower as I turned and turned," he writes, "until I felt I was back in the trenches, the houses upon either side being so much of the same color and substance as the rough ground between." That lost feeling is what struck Major Frank Isherwood, who writes his wife in December, 1914: "The trenches are a labyrinth, I have already lost myself repeatedly...you can't get out of them and walk about the country or see anything at all but two muddy walls on each side of you." What a survivor of the Salient remembers fifty years later are the walls of dirt and the ceiling of sky, and his eloquent optative cry rises as if he were still imprisoned there: "To be out of this present, ever-present, eternally present misery, this stinking world of sticky, trickling earth ceilinged by a strip of threatening sky." As the only visible theater of variety, the sky becomes all-important. It was the sight of the sky, almost alone, that had the power to persuade a man that he was not already lost in a common grave.
~ From The Great War and Modern Memory by Paul Fussell, p. 51