'improvised series of Jewish jokes'?

As I recall, Jolson is ad libbing small talk, like "Who is telling you no?" "Oh, a whole lot of Levys, I don't know them all"; "The butchers wife will be jealous of you, you see if she isn't", etc., just little snippets of what family members in a Jewish household (on film) might say to one another. No real jokes.

Mast's book is a good overview but on the individual details can be quite inaccurate and the whole thing has moments of extreme bias. In his section on Jerry Lewis, he states that most Americans cannot sit through a Lewis film, which is of course total nonsense.

My advice, especially if you're new to studying film history-use Mast's book as an overview of the major periods/people in film history, but take some of his more "opinionated" statements with a grain of salt.

Still, if I were teaching a film studies course, I would use Mast's book above any other.

Prior to this Jolson had been a great star on Broadway. He was considered to be a great singer, but some critics also described him as a comedian. He had a brilliant mind and wonderful comic ad-lib instincts. In the Blue Skies scene there was supposed to be only singing heard, but Jolson couldn't contain himself and just started to ad-lib. The producers decided to leave it in the film, and it was the thing that really made the film for audiences. As one critic said this movie was more a Singie than a Talkie, until Jolie took over. His off the cuff comments really intrigued audiences.

In that scene there were some amusing comments about Jolson wanting to take his mother to Coney Island and ride with her through the tunnel of love. But the real humor came when he told her how his success would allow her to have a better life. That he would shower her with gifts and even the butcher's wife would be jealous of her. The butcher's job was considered to be a secure one even in poor communities because even in bad times, everyone still has to eat.

He then tells her how she will be able to move to the Bronx, then considered to be an affluent section of New York City. In an attempt to assure her that she will be able to fit in, he tells her the names of some Jewish families that live there letting her know that it would be the type of neighborhood that would not shun her. He tells his mother that if he is successful the family will move to the Bronx where there is nice green grass and many people there like her, the Ginsburgs, the Guttenbergs, the Goldbergs, Oh there's a whole lotta Bergs up there. He then tells her of all the gifts he will buy her, including a nice pink dress. When she demures, he says, yes you'll wear pink, or else----------or else you'll wear pink. That last line being so indicitive of the Jolson persona. Even in his kindest moments he is still in charge, still telling you he knows best.

This casual endearing humor really resonanted with audiences. His obvious affection for his mother, his vow to remove the family from the brutality and wretched poverty of the ghetto. Just to experience something as basic as green grass would have been a thrill for the people consigned to the neighborhoods most Jews were forced to live in. This dialogue really moved viewers of the movie and provided a humanity to the characters that the silent screen alone could not. And Jolson helped provide a universality to his character. A way for the overwhelmingly gentile audiences who viewed the movie to be able able to say to themselves, hey I guess Jews really aren't so different. They're just like everyone else, they love their families and they just want a better life for their loved ones, just like all the people I know, all my Christian friends and relatives.