124 TRAVELS THROUGH 



canos, b'ecaufe the fame may be now and then feerc 

 effe&ed by the Vefuvian eruptions. Thefe ames 

 and lava beds are but coverings cf the ground, 

 which was anterior to thefe eruptions. The queftion 

 is, of what nature it was ? 



On whatever fide you fet out from Naples tra- 

 velling to the end of this volcanic covering, you 

 meet there with calcareous tufflone or lime-ftonc 

 hills, which are branches of the Apennines. Be- 

 hind monte Somma and Vefuvius, towards Sarno and 

 Nola, the ground confifts in calcareous incrufta- 

 tions, ofteocolla, and tufo-ftone, wafhed down from 

 the neighbouring Apennines j which calcareous 

 hills coming from Terracina run round the city 

 of Naples and Vefuvius, and appear again on the 

 other fide of Pompeja ; whence drawing nearer to 

 the fea, they go along the fhore ro Sorrento and 

 the fouthern parts of Italy. Even in the fea, be- 

 yond this volarric covering, there rife large calca- 

 reous rocks or iflands, fuch as Capri. Hence it is 

 probable, that the limeflone is running under 

 ground of the volcanic afhes and lavas ; and the 

 more fo, as large white lirneflones, and coarfe cu- 

 bic or calcareous fpar, are thrown out of Vefuvius, 

 and fragments of thefe ftones appear inclofed in 

 the cinericious hills and lavas. Even the ames are 

 fomewhat alkaline, as mewing fome fmall efierve- 

 fcence with acids. But 



