104 The Ohio Journal of Science [Vol. XIX, No. 2, 



district. If any lava flow underlies the Valley, it must have 

 issued from fissures in its floor. Such a fissure eruption is, 

 of course, quite within the bounds of possibility. But we have 

 now reached the stage where, in order to support our surface 

 water hypothesis, we have had to assume the presence of both 

 the lava flow, to be cooled, and the water, to be vaporized. 

 It will now be advisable to consider the other side of the question. 



Photograph by D. B. Church 



THE VALLEY OF TEN THOUSAND SMOKES. 



A corner of the Valley of Ten Thousand Smokes, looking from the rim of Novanipta 

 toward Baked Mountain, July 15, 1917. 



SMOKES ARE CONSTANT. 



A large body of lava will obviously remain hot for a long 

 time. It would be quite possible for such a mass, if it were 

 present in the Valley, to retain heat enough to continue to 

 send up clouds of steam throughout the six years which have 

 elapsed since the eruption. But it will be recognized that this 

 sort of activity would of necessity be gradually dying out. 

 One should expect, therefore, to find a sensible diminution of 

 the activity of the Valley with the lapse of time. On the 

 contrary no diminution whatever can be detected. The smokes 

 appear exactly the same now as when they were discovered. 

 Compare the pictures above, taken in succeeding years. 



