C. EASTON, "Periodicity of Winter Temperatures in Western Europe, since the year 760". 



( A. Historical curve: thirteen periods of 89 years 760—1916 taken together. 



1 B. Thermometrical curve: Paris (S. Maur) and De Bilt combined, 1852—1916. 



' C. Thermometrical curve: Paris (Observatoire) 1828-1855. 



S a. Historical curve: twelve periods of 89 years 760—1827, the great deviations only. 



/ b. Thermometrical curve: Paris— De Bilt 1852 1916, the monthly averages only. 



's «. Historical curve A, smoothed twice. 



' ,5. Thermometrical curve B, smoothed twice. 



Strongly smoothed curve of a periodicity of 89 years. 

 Strongly smoothed curve of a periodicity of 44',^ years. 



Proceedings Royal Acad. Amslenium, Vol. XX. 



