How does Gregory David Roberts use imagery in Shantaram: A Novel?

Imagery:

Through the sleepy night, and into the rose-petal dawn, the train rattled on. I watched and listened, literally rubbing shoulders with the people of the interior towns and villages. And I learned more, during those fourteen constricted and largely silent hours in the crowded economy-class section, communicating without language, than I could've learned in a month of traveling first class.

I struggled to swallow it down and then I knew; I remembered. It was the taste of hatred - my devils learn to prey. Every time we turn the key we twist the knife of fate, because every time we cage a man we close him in with hate.