I could not help it: the restlessness was in my nature; it agitated me to pain sometimes. Then my sole relief was to walk along the corridor of the third storey, backwards and forwards, safe in the silence and solitude of the spot, and allow my mind's eye to dwell on whatever bright visions rose before it—and, certainly, they were many and glowing; to let my heart be heaved by the exultant movement, which, while it swelled it in trouble, expanded it with life.
Chapter 12 · Narrator
Context
Jane explains that when restlessness became painful, she would pace the third-story corridor at Thornfield alone, letting her imagination conjure vivid scenes to compensate for the limitations of her actual life.
Analysis
Brontë gives Jane's heart physical agency—it is 'heaved' and 'swelled'—as if emotion has a body of its own that refuses to be contained. The paradox 'swelled it in trouble, expanded it with life' suggests that even painful feelings are preferable to numbness; trouble and vitality are grammatically parallel, as though they're two aspects of the same force. The pacing 'backwards and forwards' becomes a spatial emblem of being stuck, moving without going anywhere.
Essay Tip
Support a thesis that Jane romanticizes her own suffering as a form of aliveness—by describing restlessness as something that 'expanded' her, she reframes what society would call discontent as proof of a rich inner life that her circumstances can't accommodate.