Acoustic cloud

According to John Tyndall, the acoustic cloud is a change in density in the air caused by differences in humidity or temperature , which is noticeable through reflection or deflection of the sound , see sound propagation .

Such changes in density of the air also change the direction of light propagation, which is why acoustic clouds can also produce optical phenomena such as a mirage .

The term was mainly used in the 19th century, today it has become uncommon.