The Last Bottle Kiln in the Valley
There were four hundred of them within living memory. Now there is one that still fires, and the man who fires it is seventy-three.
A bottle kiln is not a kiln inside a building. The building is the kiln: a brick bottle some thirty feet high, with the firing chamber at its base and the whole structure acting as the chimney. From outside it looks like industrial architecture. From inside it is a single enormous appliance.
There were something over four thousand of them in North Staffordshire in 1910. The Clean Air Act of 1956 finished most of what economics had started, and by 1978 the last commercial firing had happened. Forty-seven survive as listed structures. One still fires.
Forty hours
A firing takes about forty hours and roughly two tonnes of coal, and it cannot be paused. Once the chamber is above about 600°C the only way out is forwards.
The sequence has not changed much since the 1880s:
- Pack the saggars — the fireclay boxes that hold the ware — and pack them evenly, or the stack shifts at temperature and takes a column of pots down with it.
- Bring the heat up slowly for the first twelve hours. Too fast and any water left in the clay turns to steam inside the body of the pot.
- Hold at top temperature, about 1,120°C, until the trial rings say otherwise. The rings are drawn out through a spy hole with an iron rod and quenched; you read the glaze on them.
- Let it fall on its own, which takes another day. Opening early cracks everything inside.
Reading the rings
There is a pyrometer now, bolted to the wall in a steel box, and the man who fires the kiln looks at it perhaps twice in forty hours. The rings tell him what he needs and the colour through the spy hole tells him the rest. Straw colour is not hot enough. Lemon is close. He describes the target as "like looking into the sun with your eyes shut", which is not a measurement and is also exactly right.
You do not learn this from a book. You learn it from standing next to someone for ten years.
He started in 1969, at fifteen, sweeping. He was allowed to touch the damper in 1974. He fired his first kiln alone in 1981, by which time the industry that trained him had largely stopped existing.
After
The kiln fires twice a year now, for a trust, and the pots go to a shop and a mailing list. The economics are not really economics. The coal costs more than the ware is worth and the insurance costs more than the coal.
There is no apprentice.