The spark flies out from under Paul's horse's hooves as they gallop along. But, as you probably guessed, this isn't just any old spark. This is a metaphor for the power of freedom and light, and all that good stuff. More specifically, it's the symbolic spark that is going to start the huge fire of the revolution.
- Line 79: The spark is just one of the many ways the poem emphasizes the importance of what Paul Revere is doing. It's a great way to represent how a small action can start a big event. We should also point out that Longfellow goes nuts with the alliteration here: check out all the s- sounds in this line: "spark," "struck," "steed."