The Rumford fireplace in the Boy Scout log house in Port Townsend.

"Rumford fireplaces are efficient and well designed. The Rumford fireplace created a sensation in London when he introduced the idea of restricting the chimney opening to increase the updraught, which was a much more efficient way to heat a room than earlier fireplaces. This was in the late 18th century. I like Rumfords and had the task of rebuilding one that was deteriorating from age and use. The best part are the wolf head tiles that serve as fresh air intake vents. It has been a couple of weeks of restoration lately as I just wrapped up repointing one side of an 1893 building in downtown Port Townsend."

..... Mike's Artisan Masonry blog