After my time in the Army , in 1970 I was enrolled in College and worked in a body shop with a friend . In that shop we heated it with a rectangular cast iron stove. We kept a night stick in it to keep a ember hot for in the morning to help it start up! GREAT memories of it and the smell of that warming fire in the morning with a cup of Joe ! My brother has a large pot bellied (cylindrical) stove in his shop at home and used it all the time and ended up needing to replace the shell . His buddy worked in a sheet metal shop and rolled a replacement shell for him . You could work in a "T" shirt during the Winter in there !