Celsius Celsius The Celsius scale, also known as the centigrade scale, is a temperature scale used by the International System of Units (SI). As an SI derived unit, it is used by all countries except the United States, the Bahamas, Belize, the Cayman Islands and Liberia. It is named after the Swedish astronomer Anders Celsius (1701–1744), who developed a similar temperature scale. The degree Celsius (°C) can refer to a specific temperature on the Celsius scale or a unit to indicate a difference between two temperatures or an uncertainty. Before being renamed to honor Anders Celsius in 1948, the unit was
Incubator (egg) roof that allowed smoke to escape, but it kept the rain out. Controlled scientific incubation required the accurate and repeatable measurement of temperature, such as the alcohol-based thermometer proposed by the French naturalist and scientist René Antoine Ferchault de Réaumur in 1730, and the temperature scale named after him. Réaumur used the thermometer in his design for an artificial incubator, presented to the Académie des sciences in 1747, and published in 1749 as "l’Art de faire éclore et d'élever en toute saison des oiseaux domestiques de toutes espèces, soit par le moyen de la chaleur du fumier, soit par le