224 BOULDER REVERIES. 



never before, how the slow, unceasing action of 

 some of nature's milder forces have modified 

 to so great an extent the surface of the earth. 

 Around him on every side is matter sand. 

 Coming in from over the lake is the force 

 wind. Slowly but surely building up about him 

 is the result of the action of force upon matter 

 hills. Thus have dunes been formed, here or 

 elsewhere, for ten thousand times ten million 

 years. 



