506 WITHIN THE EARTH'S CRUST 



A large part of the ancient crater, now known as Monte 

 Somma, was blown away, and the villas and towns near 

 the mountain were covered with the ash and cinders ejected. 

 So deep were many of these buried that their sites were 

 utterly forgotten. Pompeii and Herculaneum, after lying 

 buried and almost forgotten for hundreds of years, have 

 been recently partially uncovered. 



These fossil cities show the people of to-day how the 

 ancient Romans lived and built. The topography of the 

 country and the coast line were greatly changed by this erup- 

 tion. Pompeii formerly was a seacoast city at the mouth 

 of a river. It is now a mile or more from the sea and at a 

 considerable distance from the river. 



From the date of its first historic eruption until the present 

 time Vesuvius has had active periods and periods when 

 quiet or dormant. Sometimes the activity is mild, and at 

 other times tremendously violent. At times the material 

 ejected is fragmental and at other times streams of molten 

 lava pour down its sides. Its ever changing cone, unlike 

 that of Monte Nuovo, is composed partly of ash and partly 

 of consolidated lavas. Even as late as 1907 a tremendous 

 outpouring of ash took place which devastated a con- 

 siderable area. 



Mount Pelee. At the north end of the island of Mar- 

 tinique in the West Indies rose a conical-shaped mountain. 

 In a hollow bowl-like depression at the top lay a beautiful 

 little lake some 450 feet in circumference. The mountain 

 and lake were pleasure resorts for the people of the city of 

 St. Pierre. According to legend this mountain had been 

 violently eruptive, but in historic time there had been no 

 indication of this except one night in 1851 when the volcano 



