Vol. 15 (2023): CCCXVI. Observationes de lumine Boreali partim a se, partim ab aliis, in Suecia habitas (1733) by Anders Celsius

The fifteenth volume in the series presents a monograph by the famous meteorologist and astronomer Anders Celsius (1701–1744), founder of the centigrade temperature scale known as °C. Celsius collected observations of the aurora borealis from Swedish territories. The monograph contains a 10-page historical introduction discussing the periodicity of the phenomenon followed by a 48-page chronological account of 316 observations made in Sweden, including Finland, from 1716 to 1732. Celsius had himself made 67 of the observations; the rest had been reported by sixteen different observers. The introduction, written by Per Pippin Aspaas, contains biographical information on each of the various observers as well as a summary with extracts of Celsius’ text in English translation.