Who is the narrator, and when did the accident happen.

Dunstan Ramsay is the narrator. The accident happens when Dunstan was a child. Dunstan sees Mr. Dempster, a young priest, and his new, pregnant wife Mrs. Dempster on one of their evening walks. Because it was not considered 'proper' for a pregnant woman to be seen in broad daylight, they usually walk in the evening. Percy throws another snowball, which Dunstan dodges by jumping in front of the Dempsters.

Unfortunately, the snowball hits Mrs. Dempster in the head, knocking her to the ground. As she screams hysterically, Mr. Dempster tends to her in the street, and then leads her home.