28The structure of the reverberatory furnace

This is a one-tenth scale sectional model of the reverberatory furnace created by the Saga Domain. The reverberatory furnace is comprised of two sets of single-chimneyed dome-shaped furnaces, and in each furnace the fire and heat generated by charcoal is reverberated onto the furnace walls and the ceilings, melting the iron within. Fresh air is taken in automatically through the tall chimneys, enabling one furnace to melt more than two tons of iron at a time. However, since casting cannons requires more iron, several furnaces were put to work simultaneously. The melted iron was drawn out of the furnace into the cannon-shaped casting mold buried in the ground, and after the iron had hardened and cooled, the barrel bore was made using the power of a waterwheel; the cannon was then complete.