In Book the Second, Chapter One, Dickens writes,
After hailing the morn with this second salutation, he threw a boot at the woman as a third. It was a very muddy boot, and may introduce the odd curcumstance connected with Mr. Cruncher's domestic economy, that, whereas he often came home after banking hours with clean boots, he often got up next morning to find the same boots covered with clay.
As Jerry sleeps, his wife causes him to awaken; so,addressing her as "Aggerawayter," he asks her what she is doing. Mrs. Cruncher, who is fastidious and thoroughly scrubs their meager home, tells her husband that she is merely praying. But, this statement angers her husband who accuses her of praying against him. He tells his wife that if she "must go flopping ...down," she should "flop" in favor of her husband, not against him, for he is "an honest tradesman."
The truth is that Mrs. Cruncher realizes that Jerry is involved in some illegal business as he works in the night and returns in the early hours of the morning with muddied boots. She suspects him of grave robbing, but does not accuse him. The young son wonders, too, why Jerry's fingers are always rusty when there is no rust in the Cruncher home. Here, then, is a humorous parallel to the Resurrection motif which was seriously introduced with Dr. Manette's having been "recalled to life": Jerry resurrects cadavers from their graves for study by scientists of the time.