of 



anb 



the mountains flowing lines of beauty, the gla- 

 ciers added inconceivably to the richness of the 

 earth's resources by creating vast estates of soil. 

 It is probable that glaciers have supplied one 

 half of the productive areas of the earth with 

 soil; the mills of the glaciers have ground as 

 much rock-flour soil for the earth as wind, 

 frost, heat, and rain, all the weathering forces. 

 This flour and other coarser glacial grindings 

 were quickly changed by the chemistry of Na- 

 ture into plant-food, the staff of life for for- 

 ests and flowers. 



Glaciers have not only ground the soil but in 

 many places have carried this and spread it out 

 hundreds of miles from the place where the 

 original raw rocks were obtained. Wind and 

 water have done an enormous amount of work 

 sorting out the soil in moraines and, leaving 

 the boulders behind, this soil was scattered and 

 sifted far and wide to feed the hungry plant-life. 



At last the Glacial Winter ended, and each 

 year more snow melted and evaporated than 

 fell. Snow-line retreated up the slopes and fin- 

 ally became broken, even in the heights. To- 



257 



