Walter Lane was always baking biscuits in a stove pipe oven that he constructed in his trapper's shack. The oven captured waste heat where the biscuits were placed to bake. The oven shown is quite a pricey affair, but Walt was able to fabricate something similar for just a few dollars.
There was no way he'd allow heat to escape up the chimney without putting it to good use first. Walter was the ultimate recycler.
Stu
