In “The Glass Essay,” the speaker moves from one prison to another. Wherever she is, she’s likely to feel trapped. The theme of imprisonment links to the presence of Emily Brontë. “This is my favorite author” (Line 18), says the speaker. Yet Emily does not seem to bring the author pleasure—instead, she is plagued by anxiety. “Whenever I visit my mother / I feel I am turning into Emily Brontë” (Lines 20-21), confides the author. Emily does not offer the speaker an escape from her situation but a portal into another kind of prison. Like the speaker, intense feelings and longings beset Emily. The speaker says, “Her poetry from beginning to end is concerned with prisons, / vaults, cages, bars, curbs, bits, bolts, fetters, / locked windows, narrow frames, aching walls” (Lines 150-152). The poet-speaker and the poet-Emily are linked in this imprisonment.

Emily does not serve as an escape from the oppressive domesticity of her mother’s house; instead, she serves as a means to further the theme of imprisonment. “Well there are many ways of being held prisoner,” thinks the speaker (Line 159). For the speaker, Emily is imprisoned by, among other things, her imagination, her writing, the moor, the mystical Thou, and her antisocial personality.