My dear mother sent me a card about a month ago featuring a monkey backed up against a block of ice with the quote, "What dreadful hot weather we have! It keeps one in a continual state of inelegance." It's so nice to now know the source of that quote!
But as for my comment, I just love how this line was thrown in there. And it serves as a nice lead in to the comment about Miss Pearson and how Cassandra should not "expect too much beauty." I wonder if she was referring to the heat's effect on her appearance or if she just wasn't as pretty as everyone had expected.