Explain how Gulliver tries to prove to the king that the people of England are smart.

Gulliver tells the king of gunpowder and how it was discovered. Then he tells him how this powder could level a city and then Gulliver offers to teach the king's workmen how to make it. Gulliver's speech to prove the intelligence of the English people backfires though. The king is upset with the idea of gunpowder and lets Gulliver know that he cannot believe that Gulliver would ever entertain such an idea.