340 



THE STORY-BOOK OF SCIENCE 



inonts, we have what looks like a boiler heated by 

 some invisible furnace. In the midst of a whirlpool 



of steam the water rises 

 in a boiling flood. Sud- 

 denly the geyser mus- 

 ters all its force : there is 

 a loud explosion, and a 

 column of water six me- 

 ters in diameter spouts 

 upward to the height 

 of sixty meters, and 

 falls again in steaming 

 showers after having ex- 

 panded in the shape 

 of an immense sheaf 

 crowned with white 

 outburst lasts only a 

 liquid sheaf sinks; the 



Giant Geyser, Yellowstone 

 National Park 



vapor. This formidable 

 few moments. Soon the 

 water in the basin retires, to be swallowed up in the 

 depths of the crater, and is replaced by a column 

 of steam, furious and roaring, which spouts upward 

 with thunderous reverberations and, in its indomi- 

 table force, hurls aloft huge masses of rock that have 

 fallen into the crater, or breaks them into tiny bits. 

 The whole neighborhood is veiled in these dense ed- 

 dies of steam. Finally calm is restored and the fury 

 of the geyser abates, but only to burst forth again 

 later and repeat the same program." 



' ' That must be terrible and beautiful at the same 

 time," commented Emile. "No doubt you look at 

 this furious fountain from a long distance, so as 

 not to be struck on the back by boiling showers." 



