how is the story told in Browning's 'the laborotory'

Browning story the Laboratory is about and insane, delusional woman, who goes to an apothecary to buy some poison to kill the man she is in love with, lovers.
The setting in 'Lab' is an apothecary 'faint smokes curling' this is a use of imagery as well as the negative picture of a 'devil's smithy'  as well as her fantasying her killing these women which shows her psychotic nature. this allows the dramatic monologue to give the dark and negative atmosphere and moves it on to a understanding of her mental state.
The voices in 'Lab' are consistent of one person this is the woman that we hear throughout the dramatic monologue 'is this the poison too poison her prithee?' suggesting the need for her to ill someone, which is what we hear as this is the case building which she does through the language of 'he is with her' and the bitterness of her voice that we hear. the case building allow the story to move forward as it make her want to tell us what has happened, and how she hates these women.
The characters in 'Lab' is a woman who is dark and disturbing, her language makes you think she is psychotic, she is very bitter about her lover, 'pure death' showing how she is in love with death and romanises it. which allows the reader to to move though the dramatic monologue  by her fantasying about it whilst she is waiting for him to finish what he is doing, as well at the end her telling him to kiss her '' you may kiss me' this allows us to end the dramatic monologue knowing that she doesn't really are about the man that she supposedly loves. there is also the Browning feature of an implied listener of an apothecary, who is a man, who doesn't like the woman who scares him.
The journey in 'Lab' shows the bitter women who goes in to this apothecary to buy poison for people who have been 'laugh at me,' this helps use to push the dramatic monologue on as it help to build the case study of why she does it. It then goes on to push the story as she wait for the poison and romanticises about how she wants it to turn out, 'Soft phial' which allows to understand her different mind.the journey then shows how she isn't impressed with it 'The colour's so grim.' The journey leaves us with the idea she on her way to kill these women 'next moment I dance at the king's.'