What imagery does Brönte use to illustrate Jane's will?

Bronte makes Jane’s independent will more clear through the use of flame and iron imagery. She does this to emphasise the ‘blasphemy’ of marrying someone she does love, St. John. Standing in his presence, Bronte illustrates Jane’s feeling of entrapment, “iron shroud suffocating me”, by likening it to death, where a dark metal funeral gown threatens to suffocate her. This is significant because it demonstrates the emphasis on female thought, where her emotions are finally considered for once.