How does R.C. Sheriff make a lot of act 1 feel so amusing, and what does this convey about the mentality of the men?

The beginning of Journey’s End establishes the theme of the miserable and claustrophobic living conditions that soldiers engaged in trench warfare had to endure during WWI. The dugout in which the play takes place is gloomy, dark, cold, and damp, as illustrated by the imagery of Hardy attempting to dry his sock over a candle flame.

Compounding the miserable living conditions is the lack of decent food: this motif is introduced with Hardy and Osborne’s discussion of the need for whiskey to dilute the taste of disinfectant in the water. The men keep their spirits up by commenting ironically that there is nothing worse than having dirt in their tea, as though the reason for the dirt—falling German bombs—is less important than the inconvenience of the dirt itself.