Biographical Introduction and Summary of Contents

The fifteenth volume in the series presents a monograph by the famous meteorologist and astronomer Anders (in Latin: Andreas) Celsius (1701–1744), founder of the Centigrade temperature scale known as °C. From a young age, Celsius collected observations of the aurora borealis from Swedish territories. He participated in the editing of the Acta Literaria Sveciæ, the journal of the Royal Swedish Society of Learning and Sciences in Uppsala, in which a substantial number of observations were published. The journal articles in question were often quite short, with the aurora often inserted in lists of meteorological observations with little space for descriptions. By contrast, Celsius’ monograph contains a ten pages long historical intro­duction discussing the periodicity of the phenomenon, arguing that one should differentiate between minor and major aurorae: only the latter were visible on the European Continent and British Isles. There follows a 48-page chronological account of 316 observations made in Sweden, including Finland, during the period from 1716 to 1732. A network of observers established by the Uppsala society provided the basis for this impressive display of Swedish science. Celsius himself had made 67 of the 316 observations; the rest had been reported by sixteen other amateur and professional practitioners of science. The introduction, written by neo-Latinist and historian of science Per Pippin Aspaas, contains biographical information on each of the various observers as well as extracts of Celsius’ text in English translation.