Scale of temperature the Swedish astronomer Anders Celsius (1701–1744), who developed a similar temperature scale two years before his death. The degree Celsius (°C) can refer to a specific temperature on the Celsius scale as well as a unit to indicate a temperature "interval "(a difference between two temperatures or an uncertainty). From 1744 until 1954, 0 °C was defined as the freezing point of water and 100 °C was defined as the boiling point of water, both at a pressure of one standard atmosphere. Although these defining correlations are commonly taught in schools today, by international agreement the unit "degree Celsius" and
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