In this quote from Wuthering Heights, the speaker contrasts their own intense emotions with someone else's calm or cold demeanor. They emphasize that their blood is warm and passionate, unlike the other's icy nature. The imagery suggests a deep internal fire that cannot be subdued or transformed into mere indifference.
The speaker also highlights how the chillness of the other person affects them, inciting a lively, almost rebellious response. Their fiery nature reacts vividly to the calm exterior, indicating strong feelings and a tumultuous inner world that is stirred by the other's coldness.