How does Laura Ingalls Wilder use imagery in West from Home: Letters of Laura Ingalls Wilder to Almanzo Wilder?

Imagery:

"To cap day, as we came home on the streetcar a man sat near us who was chewing gum. He wore a stiff hat pulled down tight on his head every time he chewed, his hat moved up and down fully 2 inches, up and down, up and down, with perfect regularity as though he were worked by electricity."

"All night and all day we can hear the sirens on different islands and headlands, and the ferries and ships at anchor in the bay keep their foghorns bellowing."