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CHARLES KEYES 



differential relief effects attain maximum extremes. In this tract 

 it is that the seeming youthfulness of the lofty desert mountains is 

 at once impressed with amazing \dvidness upon the mind of the 

 observer fresh from his pluvial homeland. 



Fig. I. — Physiographic regions of New Mexico 



Once clearly discriminated, wind-graved relief expression is 

 seldom mistaken for any other kind. Its individuaHty is very 

 strong. Wind-beveled surfaces are smoother than water-formed 

 plains possibly can be. The rock floors which characterize so 

 many desert plains are phenomena as novel as they are unexpected. 



