The narrator, Lieutenant Frederick Henry, an American medic volunteering in the Italian army during World War I, observes conditions where he is stationed near the front. Soldiers often march down the road carrying heavy burdens toward the fighting, while officers speed by in motor cars—any car going particularly fast is probably carrying the King of Italy, out to monitor the fighting. The start of winter brings steady rain, resulting in a cholera epidemic in which "only" 7,000 soldiers die.
The speeding cars imply that the roads are dangerous. Rain is associated with death throughout the novel. Henry's use of the word "only" to describe 7,000 dead shows his stoicism and his need to escape the horrors of war by making light of them. It also communicates just how horrible World War 1 is. If 7,000 dead can be called "only," then how many total must have died?