The Tatsumi kilns
At the Tatsumi kiln, Naganuma san uses two types of kiln very common in traditional Japanese pottery: the anagama and the noborigama. The anagama is the oldest type of kiln: a simple single chamber built on a slight slope with the fire at the front of the kiln. Whereas the noborigama (or climbing kiln) is a series of chambers built going up a slope to capture and concentrate the heat as it rises.
Both of the kilns were built by Naganuma san over twenty years ago with the help of a specialist from Saga prefecture. You still find travelling kiln makers, but they are getting fewer and fewer. If we do manage to pin one down it would make for a fascinating conversation.
The kilns are wood-fired and require constant attention throughout firing as the temperature reaches roughly 1250ºC which consumes a huge amount of wood. Naganuma san fires alone – it used to be easy to get apprentices, but now more and more young people are moving out of the countryside – and it is extremely hard physical work. Most of the wood comes from demolition sites, waste from gardeners and similar sources.
Why go to so much trouble? Wood gives off much more fly ash and the variation in temperature and position in the kiln gives more depth to the glazes and more unpredictability to the results. Naganuma san always grins and says he is made of fire and earth - but he also hangs his shimenawa over the kiln for good fortune too!
Here you can see the wonderful depth of colour in the glaze as well as the brown stains from iron in the clay and the natural pockmarks and cracks after firing