As Darnay embarks on his ill-fated journey to France, he can feel himself becoming increasingly trapped as he draws closer to Paris. Dickens uses metaphor to evoke Darnay’s sense of imprisonment:
Not a mean village closed upon him, not a common barrier dropped across the road behind him, but he knew it to be another iron door in the series that was barred between him and England. The universal watchfulness so encompassed him, that if he had been taken in a net, or were being forwarded to his destination in a cage, he could not have felt his freedom more completely gone.
Dickens describes the many checkpoints that Darnay passes as clanking iron doors and the all-encompassing watchfulness of the French people as a cage. This pair of metaphors foreshadows Darnay’s future imprisonment by suggesting that, for all intents and purposes, Darnay has already been captured. He is trapped the moment he sets foot in France. This passage adds to the deterministic feel of the novel. Though Darnay has not yet been tried and sentenced, his family background appears to seal his fate.
Dickens uses the metaphor of the grindstone to comment on the workings of history:
The great grindstone, Earth, had turned when Mr Lorry looked out again, and the sun was red on the court-yard. But, the lesser grindstone stood alone there in the calm morning air, with a red upon it that the sun had never given, and would never take away.
Mr. Lorry is surveying the grindstone in the courtyard outside Lucie’s apartment. Earlier in the afternoon, a group of revolutionaries sharpened their bloody weapons there, dyeing the grindstone red. By referring to the Earth as a “great grindstone,” Dickens draws a parallel between the turning of the grindstone and the turning of the Earth. The passage of time and the progression of history become a bloody grindstone, suggesting that violence is cyclical and inevitable. However, though the grindstone metaphor depicts violence as a regular occurrence in history—something that has happened before and will happen again—Dickens stresses that the repetitive nature of human injustice does not make each instance of injustice less significant. No amount of time will wash away the blood that has dyed the grindstone red.