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The Ohio Journal of Science [Vol. XIX, No. 3, 



temperature which probably was very high before the explosion. 

 First, smaller particles would be cooled more rapidly in their 

 journey through the air. This would be much more important 

 at a distance than on the slopes of the volcano. Second, the 

 expansion incident to the conversion of the magma into frothy 

 pumice would absorb much heat and reduce the temperature. 

 This is probably the more important factor near the vent. 



Photograph by R. F. Griggs 



A TALL POPLAR ON WHICH ONLY A FEW BUDS SURVIVED. 



It seems incredible that so slight a leaf surface should have sufficed to keep the 



extensive trunk and roots alive for four years (July, 1916). 



