1/8 LIGHT SCIENCE FOR LEISURE HOURS. 



pets were heard ' with much other matter of a similar 

 sort. 



In the great eruption of 79, Vesuvius poured forth 

 lapilli, sand, cinders, and fragments of old lava, but no 

 new lava flowed from the crater. Nor does it appear 

 that any lava-stream was ejected during the six erup- 

 tions which took place during the following ten cen- 

 turies. In the year 1036, for the first time, Vesuvius 

 was observed to pour forth a stream of molten lava. 

 Thirteen years later, another eruption took place ; 

 then ninety years passed without disturbance, and 

 after that a long pause of 168 years. During this 

 interval, however, the volcanic system, of which 

 Vesuvius is the main but not the only vent, had been 

 disturbed twice. For it is related that in 1198 the 

 Solfatara Lake crater was in eruption: and in 1302, 

 Ischia, dormant for at least 1,400 years, showed signs 

 of new activity. For more than a year earthquakes 

 had convulsed this island from time to time, and at 

 length the disturbed region was relieved by the out- 

 burst of a lava-stream from a new vent on the south- 

 east of Ischia. The lava-stream flowed right down to 

 the sea, a distance of two miles. For two months, this 

 dreadful outburst continued to rage ; many houses 

 were destroyed ; and although the inhabitants of Ischia 

 were not completely expelled, as happened of old 

 with the Greek colonists, yet a partial emigration took 

 place. 



The next eruption of Vesuvius occurred in 1306 ; 

 and then three centuries and a quarter passed during 



