180 The National Geographic Magazine 



From F. H. Newell, U. S. Geological Survey 



A Band of About 2,000 Sheep Grazing on the Mountain Slopes of Oregon, 

 About 6,000 Feet Above Sea-level 



" Our mountains, though of little use for agriculture, provide a large amount of fine grazing 



land." 



in winter and chill us to the bone. We 

 know that northern India is thus pro- 

 tected by the Himalayas and northern 

 Italy by the Alps so that the average 

 winter temperature on the French and 

 Italian Riviera is warmer than at Rome. 

 It is questionable however whether such 

 a climatic barrier would be of any ad- 

 vantage to us as a people for our diver- 

 sity of climate tends to intensify stamina 

 and energy. Our mountains are the 

 largest sources of water power which 

 is more valuable than ever now that 

 electricity is used for the transmission 

 of power. They add largely to our 

 timber resources and though of little 

 use for agriculture they provide a large 

 amount of fine grazing land. Their 

 rock waste is spread over the surround- 

 ing plains to their enrichment and they 

 husband our water resources where they 

 are most needed. It is among the moun- 

 tains that reservoirs are to be built to 



conserve water from the melting snows 

 and glaciers and advantageously dis- 

 tribute it over the regions to be irrigated 

 which, it is estimated, ma}' reclaim 

 50,000,000 acres to fertility. 



Our mountains are partly responsible 

 for the prevailing aridity of the plateau 

 region for though the Pacific coast from 

 Puget Sound to a little south of San 

 Francisco has abundant precipitation 

 the rain clouds are wrung nearly dry 

 among the mountains so that there is 

 little moisture left to distribute over the 

 plains east of them ; but nearly half of 

 our Pacific coast to the south of San 

 Francisco is in the zone of the northeast 

 trade winds which girdle the world in 

 the Northern Hemisphere, blowing most 

 of the time as dry winds off the land in- 

 stead of coming to the land as moist 

 winds from the sea; so that even if there 

 were no high mountains in the southern 

 part of California the adjacent country 



