I wonder how Emma might find out who Miss Augusta Hawkins was - Debretts Peerage (or Seldens), might tell if she was related to one of the titled aristorcracy, but not if she was in the landed gentry (like the unexceptional Knightleys, and the Woodhouses themselves). I don't think they had "Distinguished People of Today" and know that "Whos Who" was first published in 1849, so how was Emma able to tell if Miss Hawkins was the daughter of a MP, Judge, professor, ambassador, writer, scientist, secretary of state, admiral,alderman or eminent person? He could be the mayor of the Bristol, or the Lord Lieutenant of Gloucestershire and how would Emma find out?
In the past, JulieW has mentioned some more sinister origins - and I must admit, whoSir John Hawkins was, might easily be found out - he was in the news again a couple of weeks ago, and here is a website that tracks his many decendants through the Regency era.