i6 



SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 7I 



In the following table will be found the results obtained in the 

 same manner as above for all the zone observations taken at Hump 

 Mountain and a few taken at Calama, Chile. The latter station is 

 located on the Atacama Desert in northern Chile at an elevation 

 of 2,250 meters above sea level. The air in Calama is far dryer 

 than on Hump Mountain but being on a large expanse of desert 

 where rain scarcely ever falls, dust is of course more prevalent. 

 There is in addition a sort of perpetual haze, which may have an 

 origin in distant volcanoes of the Andes range. 



