Tunnel kiln

A kiln (/kɪln/ or /kɪl/, originally pronounced "kill", with the "n" silent) is a thermally insulated chamber, a type of oven, that produces temperatures sufficient to complete some process, such as hardening, drying, or chemical changes. Kilns have been used for millennia to turn objects made from clay into pottery, tiles and bricks. Various industries use rotary kilns for pyroprocessing—to calcinate ores, to calcinate limestone to lime for cement, and to transform many other materials.

The word kiln descends from the Old English cylene (/ˈkylene/, which was adapted from the Latin culīna 'kitchen, cooking-stove, burning-place. During the Middle English Period, the "n" was not pronounced, as evidenced by kiln having frequently been spelled without the "n", Another word, "miln", a place where wheat is ground, also had a silent "n". Whereas the spelling of "miln" was changed to "mill" to match its pronunciation, "kiln" maintained its spelling, which most likely led to a common mispronunciation, which has now become commonly used. However, there are small bastions where the original pronunciation has endured. Kiln, Mississippi, a small town known for its wood drying kilns that once served the timber industry, is still referred to as "the Kill" by locals.

Unwittingly adding the "n" sound at the end of "kiln" is due to people being introduced to the word through the written language before ever hearing the actual pronunciation. Linguists call this phenomenon "reading pronunciation" where an incorrect pronunciation is read aloud, becomes widespread, eventually reported by dictionaries, and the "original pronunciation, passed from parent to child, mouth to ear, for many generations is lost."

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