Stanza 4: In the poem, these tools make up an extended metaphor of the creator and his creation of the Tyger. A blacksmith uses these tools to make objects out of super-hot metal. The word "forge" – to create or form – is a smith term as well as another name for a smith’s furnace. The smith reference also ties into all the fire imagery associated with the Tyger, and heightens the energy and danger of the Tyger’s creation. If you don’t think forging metal is hot or dangerous, you might want to visit even a modern-day steel mill.