The interplay of light and shadow is the visual language of the book. Conrad was writing at the dawn of the cinema age, and his work has a cinematic quality. The scenes are lit by flashes of lightning or the glow of a fire. A Heart of Darkness PDF allows you to study this visual technique in detail. The novella is a feast for the imagination, creating images that burn themselves into the memory. It is a hauntingly beautiful and terrifying book.