I was particularly unconvinced by this part: As recently as the 1860s, it was considered impolite to laugh in public in the United States... By the 1870s … to

I was particularly unconvinced by this part: As recently as the 1860s, it was considered impolite to laugh in public in the United States... By the 1870s … to say that someone lacked a sense of humor was seen as one of the worst things that could be said about him or her.