Franklin Pierce Sex Jokes

Joke from an 1850s quasi-pornographic newspaper:

"Why is Ex-President Pierce like the privates of a man?

Because he went in Hard and came out Soft." 

I'm not actually sure what the joke means. Perhaps monetary policy. But any Franklin Pierce sex joke must be shared.

From Donna Dennis' Licentious Gotham: Erotic Publishing and Prosecution in Nineteenth-Century New York.