The preparation would take mere minutes; the poison was within reach. But for a reason yet unknown to me, something about the letter left me unsettled.
-- Narrator - Nella (Chapter 1)

Importance: Nella admits that even though the letter she receives from Eliza is not out of the ordinary, it still makes her uncomfortable. Nella provides the poison for Eliza’s mistress and sets in motion a sequence of events that will change both of their lives.

I felt a strange connection with whomever last held the vial in their hands — an inherent kinship with the person whose fingerprints last impressed on the glass as mine did now.
-- Narrator - Caroline (Chapter 6)

Importance: Caroline is prompted by the connection she feels with the person who last held the vial to research from what apothecary it might have come. She discovers not only the story of Nella and Eliza, but also her own passion in life.

He might have succumbed to the...
-- Narrator - Eliza (Chapter 11)