Final answer:
The described passage from The Scarlet Letter exemplifies the Gothic writing feature known as use of symbolism, with the scarlet letter representing complex ideas and emotions.
Step-by-step explanation:
The passage from Nathaniel Hawthorne's The Scarlet Letter that describes the scarlet letter being 'red hot with infernal fire' and glowing at night effectively illustrates the feature of Gothic writing known as use of symbolism. The scarlet letter, as a symbol, represents sin, shame, and the intense personal and public scrutiny that Hester Prynne endures. This supernatural glow reinforces the mark's significance and the idea that her punishment is not just of this world but has infernal connotations. It adds a layer of depth to the narrative, contributing to the dark and emotional tone common in Gothic literature.