DESTRUCTION OF HERCULANEUM. 201 



sand. We think it may be admitted, then, as an es- 

 tabhshed fact, that no stream of lava has ever 

 reached Pompeii since it was first built, although 

 the town was built upon a lava foundation. 



At Herculaneum, Mr. Lyell thinks the case is 

 different; although the substance which fills the in- 

 terior of the houses and the vaults must have been 

 introduced in the state of mud, yet the superincum- 

 bent mass differs both in composition and thick- 

 ness. As Herculaneum was^ situated several miles 

 nearer to the vokanoes, it was, of course, more ex- 

 posed to be covered, not only by showers of ashes, 

 but by alluviums and streams of lava. Accordingly, 

 masses of both have accumulated on each other 

 above the city, to a depth of nowhere less than 70, 

 and in many places of 112 feet. The tuflf which 

 envelops the buildings consists of pumice mixed 

 with comminuted volcanic ashes. 



Herculaneum was discovered in 1713 by the ac- 

 cidental circumstance of sinking a well, which came 

 right down upon the theatre, where the statues of 

 Hercules and Cleopatra were found. No buildings 

 but this are open to inspection, as the Forum, Tem- 

 ple of Jupiter, and other buildings have been fill- 

 ed up with rubbish as the workmen proceeded, ow- 

 ing to the difficulty of removing it from so great a 

 depth below ground. " Both at Herculaneum and 

 Pompeii," says Lyell, " temples have been found 

 with inscriptions commemorating the rebuilding of 

 the edifices after they had been thrown down by 

 an earthquake, which happened in the reign of 

 Nero, sixteen years before the cities were over- 

 whelmed. In Pompeii, one fourth of which is now 

 laid open to the day, both the public and private 

 buildings bear testimony to the catastrophe. The 

 walls are rent, and in many places traversed by 

 fissures still open. Columns are lying on the 

 ground only half hewn from huge blocks of traver- 

 tin, and the temple for which they are designed 



Q 



