200 Physical Notices on the Bay of Naples. 



raised by the operation of subterranean heat, had not the his- 

 toriographer of Vesuvius in his work just quoted undertaken 

 to uphold that the strata of lavas, &c. merely cover the origi- 

 nal strata of the mountain no ways volcanic. Delia Torre 

 actually goes so far as to assert that the Monte Somma is in 

 its aboriginal condition, and exhibits no marks of the agency 

 of fire or of liquefaction, (Storia^ he. p. 6 and 23,) — an extra- 

 ordinary assertion, which both Sir William Hamilton and 

 Breislak have taken great pains to disprove, and have satisfac- 

 torily shown that the volcanic action has produced the strata 

 on every side as far down as man has penetrated ; and indeed, 

 what mean ideas must we have formed of the depth of the seat 

 of igneous fires, if we suppose them confined within the nar- 

 row limits of one division of a mountain of no great size, — a 

 mountain which has probably, within the memory of man, dis- 

 gorged a far greater mass than that of its own composition, 

 and which, by its visible connection with the physical state of 

 remote portions of the globe, must for ever set aside such 

 paltry schemes of philosophizing. 



To the south of Monte Cantaroni, we have the lava of 1767, 

 which stretches to the Fossa Grande ; to the north that of 

 1785, which flows into a valley presently dividing itself into 

 two, the Rio Cupa and the Fossa di Faraonte. The Fossa 

 Grande exhibits numerous sections of the strata, which are en- 

 tirely composed of a soft tufa liable to be washed away by the 

 rains, which constantly bring out the old ejected masses thrown 

 from the Monte Somma, and imbedded in the mass, frequent- 

 ly containing the finest Vesuvian minerals. The bottom and 

 sides of this ravine (for such is the meaning of the word 

 " Fossa" in this neighbourhood) are thickly planted with the 

 fine vines which cover a great part of volcano wherever the 

 lava is disintegrated, and yield, perhaps, the best of the Italian 

 wines, — the Lachryma Christi. 



At the beginning of this essay I have placed a section of 

 Mount Vesuvius in its state 1826-7, which I have compiled 

 with great labour from every source which could afford me 

 information, and the details of actual measurement, as well as 

 from an immense number of drawings and engravings from 

 the middle of the last century to the present time. I have 

 done it in imitation of Humboldt's section of the American 



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