14 CAVE AND CLIFF D WELLER S. 
These “sinks” are usually large lakes, 
and a map of the country would make one 
believe that the rivers were emptying 
into them, but in reality they only disap¬ 
pear as just stated, to reappear in the hot 
lands as the heads of rivers. Now all the 
country between the Sierra Madre and the 
“sinks,” or at least all the valley country, 
can be readily irrigated by this peren¬ 
nial flow of water. The rivers are fringed 
with trees, and the grass is in excellent 
condition, while beyond, the plains are 
treeless, the soil arid, and the prospect 
cheerless in comparison. To particular¬ 
ize : if the reader looks at the map of 
Chihuahua he will see a series of lakes 
(they are the “ sinks ” to which I refer) : 
Laguna de Guzman, Laguna (the Spanish 
for lake) de Santa Maria, Laguna de 
Patos, etc., extending nearly north and 
