Solar Magnetic Period. 



445 



these are added the Colorado-Superior, the Texas-Michigan, 

 the Florida-Nova Scotia, and the Mexican branches. On the 

 same map are placed the average position of the wave fronts 

 from the origin, in the annual mean eastward march. The 

 North High and the South Low tracks are in reality abnormal 

 outgrowths of the atmospheric circulation. 



The question is, do these tracks in general move in latitude 

 during the sun spot period % The result is that the North Low 

 and the South High belts vary in latitude directly with the 

 solar intensity, being further north at the maximum, and 

 further south at the minimum of the period ; while the North 

 High and the South Low belts vary inversely, that is are 

 further south during the maximum of sun spots. This means 

 that an increase of solar magnetic intensity generates the 

 cyclones further south, and causes the anticyclones from the 

 polar circulation to travel to the south. Precisely the same 

 remarks hold true in the annual period. 



The Table of Relative Variations in the Meteorological and 

 Magnetic Systems gives the final results of an extensive com- 

 putation, many details of which will here be omitted. " Move- 

 ment in Latitude " refers to the average geographical latitude 



