] ] I came across this article in "Persuasions:The Jane Austen Journal Online V.23, No.1 , Winter 2002" about Count Rumford. As he was mentioned in Northanger Abbey (re: fireplace)

] Thanks very much for posting this link... I did already know what a Rumford fireplace was, but had only a sketchy idea of his other adventures.

] Since even after reading this very good article it may be a little difficult to understand how a Rumford fireplace worked, maybe I can give a quick explanation. In an ordinary fireplace, the back and sides of the firebox all become heated. However, since the back is the only one that faces the room, it's the only one that radiates heat into the room.

] In a Rumford, the sides are placed at angles that allow them to also radiate heat into the room. Not only are two additional radiating surfaces gained, their placement means that the heat is radiated in an "arc" around the fireplace opening (you can feel heat off to the sides as opposed to just directly in front of the fire).

] I hope this makes sense....