Delisle scale

A thermometer scale similar to that of Réaumur, invented in 1732 by the French astronomer Joseph-Nicolas Delisle (1688–1768), author of Mémoires pour servir à l'histoire et aux progrès de l'Astronomie, de la Géographie et de la Physique (1738). He had been invited to Russia by Peter the Great. In 1732 he built a thermometer that used mercury as a working fluid. Delisle chose his scale using the temperature of boiling water as the fixed zero point and measured the contraction of the mercury (with lower temperatures) in hundred-thousandths. The Celsius scale too originally ran from zero for boiling water down to 100 for freezing water; in 1747 Linnaeus would invert the fixed points to give us the familiar scale.

The Delisle thermometers usually had 2400 graduations, appropriate to the winter in St. Petersburg. In 1738 Josias Weitbrecht (1702–1747) recalibrated the Delisle thermometer with 0 degrees as the boiling point and 150 degrees as the freezing point of water. The Delisle thermometer remained in use for almost 100 years in Russia.

Thus, the unit of this scale, the Delisle degree (sometimes spelled de Lisle), is -2/3 of a kelvin (or a degree Celsius) and absolute zero is at 559.725 Delisle degrees.

The link below shows an antique thermometre, made around 1758 by George Adams (1709-1772) of Fleet Street, London, maker of mathematical instruments for king George III (starting in 1756). It is marked in four scales: Newton, Delisle (spelled here "de Lisle"), Fahrenheit and Réaumur.

http://www.nmsi.ac.uk/piclib/imagerecord.asp?id=10413117

Other scales

Other temperature scales are Newton (~1700), Rømer (1701), Fahrenheit (1724), Réaumur (1731), Celsius (1742), Rankine (1859), kelvin (1862) and Leyden (ca. 1894?). (Note that "kelvin" is all lower case since it is an SI unit, even though it bears the name of Lord Kelvin).