Luck on the battlefield
Buford gambles and is rewarded when the reinforcements arrive on time. However, the Union suffers extremely bad fortune when Reynolds--the best officer in the army--is killed by a sniper.
The next day Lee will win the battle mainly because his reinforcements arrive on the Union’s flank by chance.
Longstreet considers the randomness of success in war when he muses: "On little things like that--a cup of water--battles were decided. Generalship? How much of a factor is it, really?" (p.190)
Also consider this Longstreet quotation: "Tomorrow we will attack an enemy that outnumbers us, an enemy that outguns us, an enemy dug in on the high ground, and let me tell you, if we win that one it will not be because of the tactics or because we are great strategists or because there is anything even remotely intelligent about the war at all. It will be a bloody miracle, a bloody miracle." (p.252)
Intuition & Simile:
"The first attack was very short: a ragged fire. Buford nodded, listening. ‘Yes. Tried to brush us off. Got a bloody nose. Now he’ll get all angry, all puffed up like a partridge.’...Buford could not see the line. He felt the attack come...and Buford could feel them reforming again, beginning for the first time to take this seriously. The next assault would be organized." (p.86) Buford does his best to read Heth’s mind.
Soldiers’ Past Experiences & Metaphor:
"Reynolds, like Lee before him, had one time commanded at the point. There was a professional air to him, the teacher approaching the class..." (p.85)