Before firebrick and the cast-iron firebox, there is earth. This bread oven was built in the workshop, entirely shaped by hand, with no permanent formwork and no prefabricated parts: a dome of raw earth mixed with straw, built on a brick hearth laid on a platform.
The method is ancient and needs no drawings. You build a sacrificial mould — a heap of sand, or here a wooden frame — cover it with earth in successive layers, then pull the mould out through the mouth once the earth is firm enough. The chimney is drawn out of the mass itself, with no added flue.
Smoothing is not cosmetic. In a bread oven, baking is done by radiant heat from the vault once the embers have been removed: the more even the inner surface, the more uniformly the heat comes back down onto the hearth. A lumpy vault bakes in patches.
It is the same principle as a masonry heater — store first, release afterwards — applied to cooking rather than heating. Many of our heaters include an oven; this one is its most basic form, and the oldest.
