Silent era movies

[Teppo]

I like old movies, and Im wondering what they really say in those movies. Sometimes I think that they would say anything, course that time they didn't have to know their lines. Just acting and speaking shit, because nobody couldn't know what they really speak. Have anybody tried to find out what people really speak in those old films?
Maybe I make myself a fool about that question, but I have to ask it, because I 've thought it so long time.