Photograph by O. F. Cook 



THE COURSE OF AN ANCIENT AQUEDUCT 



The indistinct dark line that crosses the high slope, shown about two inches below the 

 top of the photograph, represents the course of an ancient aqueduct carried for many miles 

 along a mountain wall hundreds of feet above the valley. In the foreground, near the ruined 

 town of Pumamarca, is a group of Inca storehouses. The stream in the bottom of the valley 

 is carried in a straight course along the farther side of the valley bottom. Note canals cutting 

 across mountains (see text, page 498). 



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