U. S. GEOLOGICAL SURVEY BULLETIN 611 PLATE Xxil 
Al. WHITE BLUFF OF THE COLUMBIA, 20 MILES ABOVE PASCO, WASH. 
Composed of white volcanic ash (Ellensburg formation). Man on horseback on top of bluff indicates size of 
bluff. 
B. COLUMNAR LAVA AT CACTUS SIDING, 5 MILES SOUTH OF CONNELL, WASH. 
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On cooling the lava has formed columns or sf sia which in pla kably regular. The columns stand 
cooling paris of the flow. 
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