Masonry oven India, tandoors are traditional clay ovens, although these days modern electrically fired tandoors are available. The open-topped tandoor is a transitional design between the earth oven and the Roman-plan masonry oven. In the precolumbian Americas, similar ovens were often made of clay or adobe and are now referred to by the Spanish term "horno" (meaning "oven"). Horns are also traditional in the American Southwest. The traditional direct-fired masonry design is often called a "Roman" or "black" oven and dates in Western culture to at least the Roman Republic. It is known as a black oven because the fire generates soot
Masonry oven modular (and sometimes portable) variant—essentially a large, upside-down clay pot with an door opening cut into the side. They were often surrounded with brick as they were built into English chimneys, allowing coals and ashes to be swept onto the common hearth, and smoke to go into the chimney. "Like the Athenian cooking bell and the primitive quern, the rough clay oven had its counterparts for several thousand years, among its descendants being our own seventeenth-century Devon gravel-tempered clay wall ovens... Built into the side wall of the open hearth so that from the front only the opening was visible,