196 LIGHT SCIENCE FOR LEISURE HOURS. 



but the greater part imagined that the last and eternal 

 night was come, which was to destroy the gods and 

 the world together. " At length a light appeared, 

 which was not, however, the day, but the forerunner 

 of an outburst of flames. These presently disappeared, 

 and again the thick darkness spread over the scene. 

 Ashes fell heavily upon the fugitives, so that they 

 were in danger of being crushed and buried in the 

 thick layer rapidly covering the whole country. Many 

 hours passed before the dreadful darkness began slowly 

 to be dissipated. "When at length day returned, and 

 the sun was seen faintly shining through the over- 

 hanging canopy of ashes, "every object seemed 

 changed, being covered over with white ashes as with 

 a deep snow." 



It is most remarkable that Pliny makes no mention 

 in his letter of the destruction of the two populous 

 and important cities, Pompeii and Herculaneum. We 

 have seen that at Stabise a shower of ashes fell so 

 heavily that several days before the end of the eruption 

 the court leading to the elder Pliny's room was begin- 

 ning to be filled up ; and when the eruption ceased, 

 Stabise was completely overwhelmed. Far more sud- 

 den, however, was the destruction of Pompeii and 

 Herculaneum. 



It would seem that the two cities were first shaken 

 violently by the throes of the disturbed mountain. 

 The signs of such a catastrophe have been very com- 



