Bleak House is obsessed with appearances. Characters' features are scrutinized by narrators, by mirrors, by people watching them and spying on them, and even through artwork that represents them. Geographical and topographical landmarks are primarily identified by sight, and the ability to quickly orient oneself visually is crucial to the very survival of characters forced to find their way through hostile terrain. Still, outer looks and inner morality do not always coincide, as the novel flirts with mildly overturning some of the staunchest Victorian stereotypes about appearance.
In the novel, characters' reactions to what they are seeing are so predictable and expected that we don't actually need any of the narrator's descriptions of people and places in order to immediately understand what they look like.