The writer's description of the way the army filled the valley like a smoking river
The writer uses a simile in his description of the way in which the army filled up the vast valley below him directly comparing the same to a smoking river: "He crawled upward on his belly over cool rocks out into the sunlight, and suddenly he was in the open and he could see for miles, and there was the whole vast army below him, filling the valley like a smoking river." This particular comparison enhances imagery making the description more compelling.
The spiked flags and guidons like a great chopped bristly snake
After using a simile to directly compare the mass of soldier in the valley to a smoking river, the writer goes on to provide a vivid description of the river as it stretches, meandering farther road beyond the blue hills: "It came out of a blue rainstorm in the east and overflowed the narrow valley road, coiling along a stream, narrowing and choking a white bridge, fading out into the yellowish dust of June but still visible on the farther road beyond the blue hills, spiked with flags and guidons like a great chopped bristly snake, the snake ending headless in a blue wall of summer rain."
Dust hung above the army like a yellow veil
Following the overly hot day, the narrator uses a simile in which they compare the way the dust rose above the army to a yellow veil. The comparison facilitates imagery and enhances the reader's perception of the weather: "The day was murderously hot and there was no wind and the dust hung above the army like a yellow veil."
The pressure of the army behind the spy building like water behind a cracking dam
After the spy leaves the army behind on his trip, his horse is tired. However, the looming threat of the army discovering him is implicit. The narrator compares the pressure he feels to leave to that of water building behind a cracking dam. This simile enhances imagery and also enables the reader understand the gravity of the situation: "And yet there was the pressure of that great blue army behind him, building like water behind a cracking dam. He rode out into the open, into the land between the armies."
Longstreet's description of the spy's face
After Longstreet is awakened as he had instructed, he remembers how the spy had looked like. In his description, the writer directly compares the spy's tiny frame and face to a weasel. In addition to enhancing imagery, the description provides a deep contrast to Longstreet's own big and muscular form: "Longstreet got up quickly and put on the old blue robe and the carpet slippers. He was a very big man and he was full-bearded and wild-haired. He thought of the last time he'd seen the spy, back in Virginia, tiny man with a face like a weasel."
