How does Norman Maclean use imagery in Young Men & Fire?

Imagery:

"Although young men died like squirrels in Mann Gulch, the Mann Gulch Fire should not end there, smoke drifting away and leaving terror without consolation of explanation, and controversy without lasting settlement."

"Some fire whirls, not all of them, are flame throwers."

"The most strange and wonderful thing on the hillside as the escape fire swept up it, shutting it out of sight in smoke and heat, is that a spot of it remained cool."