RED MOUNTAIN, ARIZONA 



143 



Each explosion added a thin coating of fragments that were inti- 

 mately intermingled in the air before falling to the mountain slopes. 



Fig. 4. — Close range view in Red Mountain, showing pillars of volcanic tuff 

 capped by angular blocks of lava. 



At very close range (Fig. 4) the surface of the tuff appears rough 

 and the bedding is indistinct. Certain explosions contributed 

 large quantities of angular blocks which now characterize different 



