Thanks for that link and picture, Cheryl. There's a fair amount more about the intriguing Count Rumford in the archives at L&T.

The point that comes out here, I think, is that Rumfords were new at the time of NA, so General Tilney was quick to install improvements. The Rumford stove was far more efficient than the old fireplace with its ample width, which sent nearly all the heat straight up the chimney.