St. John's University in Collegeville is home to the largest woodburning kiln in North America. The kiln holds more than 5,000 pots in its three chambers. A new book called "Body of Clay, Soul of Fire" tells the story of the kiln and Richard Bresnahan, the local potter and teacher who helped build it. Bresnahan grew up in North Dakota and studied ceramics at St. John's in the early 1970s. He earned the title "master potter" during a four-year apprenticeship with a thirteenth-generation potter in Japan. Bresnahan says that in order to understand why the kiln works so well, you have to understand what it DOESN'T do well: