Ice cube

An ice cube is a small, roughly cube-shaped piece of ice (frozen water), conventionally used to cool beverages. Ice cubes are sometimes preferred over crushed ice because they melt more slowly; they are standard in mixed drinks that call for ice, in which case the drink is said to be "on the rocks."

American physician and humanitarian John Gorrie built a refrigerator in 1844 with the purpose of cooling air. His refrigerator produced ice which he hung from the ceiling in a basin. Gorrie can be considered the creator of ice cubes, but his aim was not to cool drinks: he used the ice to lower the ambient room temperature. During his time, a dominant idea was that bad air quality caused disease. Therefore, in order to help treat sickness, he pushed for the draining of swamps and the cooling of sickrooms.

Ice cubes are produced domestically by filling an ice cube tray with water and placing it in a freezer. Many freezers also come equipped with an icemaker, which produces ice cubes automatically and stores them in a bin from which they can be dispensed directly into a glass.

Ice cube trays are designed to be filled with water, then placed in a freezer until the water freezes to ice, producing ice cubes. Trays are often flexible, so the frozen cubes can be easily removed by flexing the tray. "Twist" ice trays have a simple spring-loaded mechanism with a lever that is used to turn the tray upside down and flex at the same time such that the cubes drop are collected in a removable tray below and return the ice cube tray to its upright position without removing it from the freezer, which can save time and reduces accidents and mess, though the tray has to be removed to be collected and the ice cube tray still has to be removed to be refilled. An alternative system is an aluminium tray with a lever that raises the ice cubes, freeing them from the tray. A motorized version of this is found in most automatic ice-making freezers.

While the usual shape of the ice 'cube' is roughly cubical, there are trays that dispense hemispherical or cylindrical blocks. These are commonly referred to as "ice tubes". Some novelty trays produce blocks of ice in seasonal, festive or other shapes. There is also the possibility to freeze different edible items inside the ice cubes, both at home and commercial production.

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Wikipedia