Jalousie window Jalousie window A jalousie window (, ) or louvre window (Australia, New Zealand, Pacific Islands, Southeast Asia, United Kingdom) is a window composed of parallel glass, acrylic, or wooden louvres set in a frame. The louvres are joined onto a track so that they may be tilted open and shut in unison to control airflow, usually by turning a crank. Jalousie is the French word for jealousy. It originated in 18th century France from the Italian word "geloso", which means jealous, or screen, as in to screen something from view. Supposedly because of their slatted louvres, jalousie windows protect the
Types of volcanic eruptions Types of volcanic eruptions Several types of volcanic eruptions—during which lava, tephra (ash, lapilli, volcanic bombs and volcanic blocks), and assorted gases are expelled from a volcanic vent or fissure—have been distinguished by volcanologists. These are often named after famous volcanoes where that type of behavior has been observed. Some volcanoes may exhibit only one characteristic type of eruption during a period of activity, while others may display an entire sequence of types all in one eruptive series. There are three different types of eruptions. The most well-observed are magmatic eruptions, which involve the decompression of gas within magma that