Anagama Kiln in New Jersey, USA. Japan from China via Korea in the 5th century. It is a version of the climbing dragon kiln of south China, whose further development was also copied, for example in breaking up touched with fire pdf free download firing space into a series of chambers in the noborigama kiln.
Although the term “firebox” is used to describe the space for the fire, there is no physical structure separating the stoking space from the pottery space. The term anagama describes single-chamber kilns built in a sloping tunnel shape.
In fact, ancient kilns were sometimes built by digging tunnels into banks of clay. The anagama is fueled with firewood, in contrast to the electric or gas-fueled kilns commonly used by most contemporary potters. A continuous supply of fuel is needed for firing, as wood thrown into the hot kiln is consumed very rapidly. Stoking occurs round the clock until a variety of variables are achieved including the way the fired pots look inside the kiln, the temperatures reached and sustained, the amount of ash applied, the wetness of the walls and the pots, etc.
Wood ash settles on the pieces during the firing, and the complex interaction between flame, ash, and the minerals of the clay body forms a natural ash glaze. This glaze may show great variation in color, texture, and thickness, ranging from smooth and glossy to rough and sharp. The placement of pieces within the kiln distinctly affects the pottery’s appearance, as pieces closer to the firebox may receive heavy coats of ash, or even be immersed in embers, while others deeper in the kiln may only be softly touched by ash effects.
It is said that loading an anagama kiln is the most difficult part of the firing. The potter must imagine the flame path as it rushes through the kiln, and use this sense to paint the pieces with fire. The length of the firing depends on the volume of the kiln and may take anywhere from 48 hours to 12 or more days.
The kiln generally takes the same amount of time to cool down. Records of historic firings in large Asian kilns shared by several village potters describe several weeks of steady stoking per firing. One variant on the anagama style is the waritake kiln.