Jan., 1919] Effects of the Eruption on Vegetation 



207 



no evidence remains to indicate the cause of the death of this 

 forest. Its general aspect is much like that of the forests whose 

 destruction has been attributed to blasts from the volcano, 

 but differs in that here projecting shoulders of the mountains, 

 etc., seem to have given little if any protection to the trees 

 behind them. 



Halfway up the Valley, however, we found a mountain- 

 side which had every appearance of having been swept by a 

 fire that had blackened the surface of all the remains of the 

 vegetation, which had consisted of herbs and dwarf shrubs. 



Photograph by R. F. Griggs 



MAT OF VEGETATION- REDUCED TO CHARCOAL BENEATH 



THE MUD FLOW. 

 The original surface of the soil has been uncovered by erosion. 



This was the last sign of plant life found in the Valley, for 

 further up the rocky hills were all absolutely devoid of plant 

 remains. Unless they were originally totally barren, which 

 seems impossible, they must have been so thoroughly burned 

 over that all plant remains were consumed. While it may be 

 somewhat uncertain how large an area was so completely 

 steriHzed as this, there can be little doubt but that such was 

 the fate of all the district whose rocks were baked red by the 

 heat. 



One cannot consider these evidences of consuming heat with- 

 out speculating as to the exact conditions under which it worked ; 



