The natural world thereby provides the setting within which Henry's personal and military experiences can take place. Natural changes from dryness to wetness are paralleled in the plot by both Catherine's pregnancy and the corrupt horse races. Similarly, the war with Austria goes well for the Italians until Henry describes the corruption of the horse races, a corruption that permeates every level of the Italian army and political machine. This structure is complemented by natural symbols that substitute for emotions or feelings. The most important of these symbols is that of rain.
Rain represents death and all the accompanying emotions of grief, pain, and despair.
Death is both brought by rain and can be considered analogous to it. Catherine is the first person to make this analogy explicit when she tells Henry that she is afraid of the rain. Although Henry dismisses her words at the time, they continue to haunt the novel up until she dies. The novel thus ends with rain being used as a substitute for Catherine's death. Rain is also symbolically used by Hemingway to understate the obvious.