The passage begins with Winnie being horribly placating in blaming the accident that has just happened on the horse pulling their cab, saying, “This isn’t a very good horse.” We can see that she doesn’t truly believe that the accident was the horse’s fault, as she says this, “At last,” implying that she is only saying something to break the silence in which “time itself seemed to stand still.”
After Winnie breaks the silence, the driver begins to whip the horse again. Stevie is in a state of shock at first, shown by his “vacant mouth.” He then begins to get out of this state, saying to the driver, “Don’t.” He is not hesitant, but afraid, also shown by the author’s diction. Conrad writes that Stevie “ejaculate[s] earnestly.” This, paired with the driver not hearing him and having had a, “vacant mouth,” insists that he is not at all hesitant about telling the driver to stop, but is shocked and somewhat scared.
The reader is reminded of the earlier implication that Stevie’s father used to beat Stevie and his sister Winnie in their childhood. This happens in the driver’s whipping of the horse, and also the apparent cruelty of the driver, since he doesn’t even stop when he sees how much it bothers Stevie.
Stevie finally is sure to have caught his attention. He says twice more that the driver, “mustn’t whip.” The driver considers what Stevie has said and then proceeds in whipping. The driver even repeats