762 



THE AMERICAN NATURALIST [Vol. LI 



Walker,^ the director general of observatories for India, has 

 made a great advance in the investigation of the possible rela- 

 tionship between the number of sunspots and meteorological phe- 

 nomena by applying the modern methods of correlation to the 

 problem. 



I have tabulated his three series of correlations for a large 

 number of stations widely distributed over the earth, with the 

 results given in the accompanying table. 



Remembering that correlation is measured on a scale of — 1 to 

 -f 1, this table shows at once that there is no uniformity for the 

 globe as a whole in the correlations between number of sunspots 

 and either of the climatic factors considered. Instead coeffi- 

 cients for some stations are positive while those for others are 

 negative. Thus as far as the data available go, they indicate 

 that in some regions rainfall, temperature or barometric pres- 

 sure are higher in periods of larger numbers of sunspots, w^hereas 

 in other regions they are lower. The magnitude of the coeffi- 

 cients is generally low.* Over thirty per cent, of the constants 



