How does Colleen McCullough use imagery in The Thorn Birds?

Example of Imagery:

"Stooping, he groped for the rifle, remembering it wasn't loaded. The boar stood perfectly still, its little reddened eyes mad with pain, the great yellow tusks sharp and curving upward in a half circle. Stuart's horse neighed, smelling the beast; the pig's massive head swung to watch it, then lowered for the charge." Chapter 9, pg. 261