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
Ceramic water filter with foreign material. The two most common types of ceramic water filter are pot-type and candle-type filters. Ceramic filter systems consist of a porous ceramic filter that is attached to, or sits on top of a plastic or ceramic receptacle. Contaminated water is poured into a top container. It passes through the filter(s) into the receptacle below. The lower receptacle usually is fitted with a tap. Contaminants larger than the minute holes of the ceramic structure will remain in the top half of the unit. The filter(s) can be cleaned by brushing them with a soft brush and rinsing them