Dillard conveys the intensity of this encounter by slowing down the moment. She builds tension by characterizing the weasel down to the tiniest detail (there was just a dot of chin, maybe two hairs' worth), and creating a parallel between herself and the weasel (The weasel was stunned into stillness...I was stunned into stillness). Although this incident took a matter of 60 seconds, we are reading for much longer, wondering what will happen next.