238 THE BEAtJTIES OF NATURE chap, vi 



The most imposing crater in the world is 

 probably that of Kilauea, at a height of 

 about 4000 feet on the side of Mouna Loa, 

 in the Island of Hawaii. It has a diameter 

 of 2 miles, and is elliptic in outline, with a 

 longer axis of about 3, and a circumference 

 of about 7 miles. The interior is a great 

 lake of lava, the level of which is constantly 

 changing. Generally, it stands about 800 

 feet below the edge, and the depth is about 

 1400 feet. The heat is intense, and, espe- 

 cially at night, when the clouds are coloured 

 scarlet by the reflection from the molten 

 lava, the effect is said to be magnificent. 

 Gradually the lava mounts in the crater 

 until it either bursts through the side or 

 runs over the edge, after which the crater 

 remains empty, sometimes for years. 



A lava stream flows down the slope of 

 the mountain like a burning river, at first 

 rapidly, but as it cools, scorise gradually 

 form, and at length the molten matter 

 covers itself completely (Fig. 22), both above 

 and at the sides, with a solid crust, within 

 which, as in a tunnel, it continues to flow 



