The interrupted conception and the clock
At the moment Tristram is being conceived, his mother asks his father whether he has remembered to wind the clock, because Walter winds it on the first Sunday of each month and then does his marital duty the same night, so she has come to associate the two. Walter, who believes a child's temperament depends on the father's concentration during conception, blames this interruption for scattering the animal spirits and producing a son destined for misfortune. The novel opens on this episode as the first link in a chain of accidents that shapes Tristram's whole life.