RISE OF MOLTEN ROCK TO THE EARTH'S SURFACE 131 



The culmination of the eruption came in the evening of April 7, 

 when, to the accompaniment of light earthquakes felt as far as 

 Naples, lava issued for the first time in great volume from a mouth 

 more than halfway 

 down the mountain side 

 (Fig. 132 /), and thus 

 began the drainage of 

 the chimney. At about 

 the same time with loud 

 detonations a huge 



black cloud rose above 

 the crater in connection 

 with heavy explosions, 

 and a rain of cinder was 

 general in the region 

 about the mountain but 

 especially within the 

 northeast quadrant. 

 Those who were so for- 

 tunate as to be in Pom- 

 peii had a clear view of 

 the mountain's summit 

 where red hot masses of 

 lava were thrown far 

 into the air. The direc- 

 tion of these projections 

 was reported to have 

 been not directly up- 

 ward, but inclined 

 toward the northeast 

 quadrant of the moun- 

 tain; but since with a 

 northeast surface wind 

 the heaviest deposit of 

 ash and dust should 

 have been upon the southwestern quadrant of the mountain, it 

 is evident that the material was carried upward until it reached 

 the contrary upper currents of the atmosphere, to be by them dis- 

 tributed. 



FIG. 132. Map of Vesuvius, showing the position 

 and order of formation of the lava mouths upon 

 its flanks during the eruption of 1906 (after 

 Johnston-Lavis) . 



