In Chapter 2 of Book I, "The Mail," the impressions created are those of mud and mist. The horses pulling the Dover mail coach, strained,
With drooping heads and tremulous tails, they mashed their way through the thick mud, floundering and stumbling between whiles as if they were falling to pieces at the larger joints.
As the horses become mired in the mud, a "steaming mist" forms "like an evil spirit, seeking rest and finding none." This mist makes
its slow way through the air in ripples that visibly followed and overspread one another, as the waves of an unwholesome sea might do.
The visual images of mud and mist cast a thick cover over the night and cloud the identities of the occupants of the Dover mail who are also wrapped against the cold, fearful of highwaymen who might emerge out of this sinister atmosphere. When they hear the sound of a horse approaching at a gallop, the guard atop the coach cocks his blunderbuss, anticipating a robber.
Chapter 2 of Book I is part of the motif of Darkness and Shadows, a motif that creates a mood of fear and apprehension in "The Mail" as the passengers hide from one another behind wrappers and Jerry Cruncher emerges from the murky mist with a message for one of the strangers in the coach. And, the message is strange and cause for anxiety: "Recalled to Life." Clearly, the imagery of mud and mist contribute to the mystery of this message.