The Thermometer Scale of de l'Isle

Abstract

IN NATURE of September 7, p. 365, Dr. N. V. Nordenmark is credited with the remark ” that the thermometer of Anders Celsius used the scale of de l'Isle, the freezing point being at 100°, the boiling point at 0°”. As a matter of fact the scale of de l'Isle (who was a member of the Academy of Sciences of St. Petersburg from 1725 until 1747, when he returned to Paris) had the freezing point at 150°, the boiling point at 0°. De l'Isle's thermometer was used at the time in Russia. About 1750, M. V. Lomonosov constructed a thermometer with the inverted scale of de l'Isle, that is, with the boiling point at 150° and the freezing point at 0°, and used it in all his physico-chemical experiments.