40 VOLCANOES 



Loa and Kilauea. Here the eruptions are usually not heralded by 

 earthquakes ; the lava is remarkably fluid and simply wells up over 

 the sides of the crater, pouring down the sides of the mountain in 

 streams which flow for many miles. More commonly the walls of 

 the crater are unable to withstand the enormous pressure of the 

 lava column, and the molten mass breaks through at some level 

 below the crater, rising through the fissure in giant fountains, 



Fig. 8. — Crater-floor of Kilauea, showing the lava lake, Hale-mau-mau. (Photo- 

 graph by Libbey.) 



sometimes iooo feet high. Even in the ordinary activity of 

 Kilauea jets of 30 and 40 feet in height are thrown up. Hardly 

 any ashes or other fragmental products are formed, but the clouds 

 of steam, the invariable accompaniments of volcanic outbursts, are 

 present. 



Between such extremes as the Hawaiian volcanoes, on -the one 

 hand, and the explosive East Indian type (Krakatoa), on the 

 other, we may find every intermediate gradation. Everywhere 

 imprisoned steam appears to be an important agent, while the 



