Why is Huck’s explanation of real kings full of hilarity? (CH 20-23)

Are you not referring to cha 14? Huck tells Jim all about kings and other aristocratic personages, and Jim is very impressed and interested. I read considerable to Jim about kings and dukes and earls and such, and how gaudy they dressed, and how much style they put on, and called each other your majesty, and your grace, and your lord- ship, and so on, ‘stead of mister; and Jim’s eyes bugged out, and he was interested. He says:

“I didn’ know dey was so many un um."