Robert rides with a bugler named Willie Poole, who chose active duty over joining the military band. The air becomes contaminated with a thick, foul-smelling green fog that disorients the men and causes them to lose their bearings. Robert wonders if it is a mustard gas attack, but Poole tells him that it is probably chlorine emanating naturally from the clay in the ground.
The soldiers’ deprivation of something as basic as breathable air shows the constant danger they face at war. The similarity of mustard gas to the natural gas from the ground implies that the enemy forces, like nature, are impartial and unstoppable in their warfare tactics.
Suddenly, massive flocks of birds begin to fly out of the ditches around Robert and Poole, adding to the disorienting, ominous atmosphere of the fog. Robert tells an orderly to go back and look for the other men, and Poole gives him his bugle as a means of signaling to them through the fog.
The presence of the birds, combined with the dense fog, foreshadows uncertain danger for Robert and his men, again highlighting the unpredictable risks that soldiers face while doing something as simple as riding down a road.
Eventually, junior officer Levitt emerges with Poole’s bugle and tells Robert that the orderly and his horse drowned to death because Robert had led the men on a wrong turn through a gap in a dike. While Robert is ashamed of his error in judgment, Levitt jokes that he is glad to have the bugle because, since it could be anyone blowing it, the Germans will not shoot at him. Poole tells him that the Germans are still far away, and Levitt is disappointed because he, like most soldiers, does not feel like he is really at war unless he is in danger.
Robert’s tendency for self-blame manifests again, as he feels that he is responsible for the orderly’s death. This is the first of many losses that Robert will experience at war—his reaction to this one shows that he has not been desensitized to the trauma. Levitt’s disappointment at not being in danger suggests that the orderly’s death has not affected him in the same way, and that he too is motivated by a desire for a heroic legacy.