How does Sarah Dunant use imagery in The Birth of Venus: A Novel?

Examples of Imagery:

"With Charles and his army on the Tuscan border and panic sniffing around the city gates, Florence took herself to Church."

"A whisper went up toward us, and Erila, more attuned than I to the speed of male violence, grabbed and pulled me through the crowd until we reached the crack in the door and spit ourselves out, safe but shaking, into the cool sunshine of a bright December morning in the New Jerusalem."