To suggest that the Belpaire firebox was not a success is a bit misleading. It was very successful, but not widely adopted. For years modelers have been guilty of making this a generic name for any common cast steel truck sideframe. Bituminous - Soft coal. From the Latin for the same word that gave us bitumen , meaning a tarry substance like asphalt.
Soft coal burns with a smoky flame.
Most coal mined today is bituminous. Also see anthracite . According to their ad in a 1947 Life , the company was created by Valentin Blatz in Milwaukee, in 1851. Moody's 1945 Industrial Manual said that by that time, Blatz was a subsidiary of Schenley Distributing. According to Terry Metcalfe, the UP used these on new box cars built in '39, perhaps the earliest use of the Blaw-Knox.