The village of Sannai, consisting of people at all levels of the iron production process, was built around the ironworks as the center of production. The location was purposefully set near an expanse of trees for charcoal, iron sand, flowing water, and the conditions for convenient shipping of completed iron and food importation.
In short, the people of Sannai built a village specifically geared toward iron production.
The population of the village was different based on whether it was in its prime or during its decline, however it was thought to be a rather small village (current population: 25).
The average house was 3.3 m2, and workers lived with their families.
Farmers from neighboring towns would come to the village to sell their crops, and people would come and go bringing in clay to build the furnace as well as iron sand and charcoal.
Many facets of life in Sannai were dictated by a set of rules called “shimariai,” meaning “to bind one another.” Some examples are below.
By creating and promising to abide by such rules, the people of Sannai upheld public morals.
The following were written regarding wages.
Tatara iron production requires about 15 tons of charcoal for one production cycle, and that charcoal is made using a kiln.
Those tasked with making this charcoal are called “Yamako.”
First, workers construct a large, elliptical kiln out of clay and stones. The walls are about 1 meter thick, and a temporary roof is made using baby bamboo and other sticks.
The building process takes half a month. To make a kiln to fire 1.8 tons of charcoal requires the work of 40 people.
It takes 14 people to collect the necessary amount of branches that become charcoal. The Yamako also must cut the branches to length (150 cm) and carry them to the kiln.
About 20 kilns of this size are required to provide enough charcoal to fuel the ironworks.
“Murage” is the Japanese name for the manager of the ironworks.
There is a saying, “First furnace, second clay, third murage” or “First clay, second air, third murage.” In either case the clay used to build the furnace and the air pumped into it are stressed more than the skill of the murage. However, whether good ingredients are chosen and bellows are controlled well is up to the murage.
In order, tatara iron making consists of laying the foundation, building the furnace, 3 days and 3 nights of production, and removing finished metal. This is all done under the direction of the murage. After burning wood where the furnace will go and patting down the ash using a long stick called a “shinai,” the furnace is built in three levels, base, middle, and top. The quality of the clay was so vital as to heavily influence the chances of success or failure, so the role of the murage is crucial.
Air, which flows through the bellows built on either side of the furnace, is not allowed to stop during the 3 days and nights of production and requires the most of the murage’s attention. 11 workers add iron sand and charcoal and remove impurities under his command.
Iron sand inside the furnace reacts with oxygen from the burning charcoal to become iron. The murage adjusts the amount of air flowing through the bellows and strength of the fire by constantly watching the color and strength of the flames, checking the 40 holes at the base, or “hodo-ana,” for changes, and judge conditions inside the furnace by listening to the sound when iron sand is added. The iron inside constantly changes shape as it grows, so the air, and placement and amount of added iron sand and charcoal has to be adjusted in small increments. The current murage, Akira Kihara calls these adjustments “The Path of Fire,” which only a murage can learn through experience and intuition.
Choosing the ingredients and building the furnace, and the 3 days and nights of uninterrupted labor are all done under the direction of the murage. Success or failure rides on his leadership.
When conditions for iron making are unfavorable, the murage walks barefoot to the small shrine of Kanayago, in Sannai Village to pray for success.
Kanayago is the Shinto spirit of iron. Tales say that Kanayago is jealous of young women, so they are not allowed to work the tatara, and meals during production are to be brought by young girls or older women. Long ago, workers maintained a pond where Kanayago was said to use as a mirror to do her makeup. This was proof of their strong belief in her power.
Kanayago represents the idea that tatara iron making is always subject to the uncertainties of nature, and even the most skilled murage cannot escape from this fact.
