THE COUNTRY OF THE SHEPHERDS 49 



The oases become crowded with men and beasts just when they 

 can ill afford to support them. The alfalfa meadows become over- 

 stocked, and cattle become lean and almost worthless. But there 

 is at least bare subsistence. By contrast, if extreme and pro- 

 longed drought prevails, some of the people are driven forth to 

 more favored spots. At Vallenar in central Chile some of the 

 workmen in extreme years go up to the nitrate pampa; in wet 

 years they return. When the agents of the nitrate companies hear 

 of hard times in a desert valley they offer employment to the 

 stricken people. It not infrequently happens that when there are 

 droughts in desert Chile there are abundant rains in Argentina 

 on the other side of the Cordillera. There has therefore been for 

 many generations an irregular and slight, though definite, shift- 

 ing of population from one side of the mountains to the other as 

 periods of drought and periods of rain alternated in the two 

 regions. Some think there is satisfactory evidence to prove that 

 a number of the great Mongolian emigrations took place in wet 

 years when pasture was abundant and when the pastoral nomad 

 found it easy to travel. On the other hand it has been urged that 

 the cause of many emigrations was prolonged periods of drought 

 when the choice lay between starvation and flight. It is evident 

 from the foregoing that both views may be correct in spite of the 

 fact that identical effects are attributed to opposite causes. 



It is still an open question whether security or insecurity is 

 more favorable for the broad distribution of the Peruvian Indians 

 of the mountain zone which forms the subject of this chapter. Cer- 

 tainly both tend to make the remoter places better known. Tradi- 

 tion has it that, in the days of intertribal conflict before the Con- 

 quest, fugitives fled into the high mountain pastures and lived in 

 hidden places and in caves. Life was insecure and relief was 

 sought in flight. On the other hand peace has brought security 

 to life. The trails are now safe. A shepherd may drive his flock 

 anywhere. He no longer has any one to fear in his search for new 

 pastures. It would perhaps be safe to conclude that there is 

 equally broad distribution of men in the mountain pastures in time 

 of peace and in time of war. There is, however, a difference in 



