Ch, X.] TERTIARY FORMATIONS OF CAMPANIA. 119 



we pointed out that, on the shores of the Bay of Baiae, there 

 are recent tufaceous strata filled with fabricated articles, min- 

 gled with marine shells. It was also shown that the sea has 

 been making gradual advances upon the coast, not only sweep- 

 ing away the soft tuffs of the Bay of Baise, but excavating 

 precipitous cliffs, where the hard Ischian and Vesuvian lavas 

 have flowed down into the deep. 



These events, we shall be told, although interesting, are the 

 results of operations on a very inferior scale to those indicated 

 by geological monuments. When we examine this same re- 

 gion, it will be said, we find that the ancient cone of Vesuvius, 

 called Somma, is larger than the modern cone, and is inter- 

 sected by a greater number of dikes, the hills of unknown 

 antiquity, such as Astroni, the Solfatara, and Monte Barbara, 

 formed by separate eruptions, in different parts of the Phle- 

 grsean fields, far outnumber those of similar origin, which are 

 recorded to have been thrown up within the historical era. 

 In place of modern tuffs of slight thickness, and single flows 

 of lava, we find, amongst the older formations, hills from 500 

 to more than 2000 feet in height, composed of an immense 

 series of tufaceous strata, alternating with distinct lava-cur- 

 rents. We have evidence that in the lapse of past ages, 

 districts, not merely a few miles square, were upraised to the 

 height of 20 or 30 feet above their former level, but extensive 

 and mountainous countries were uplifted to an elevation of more 

 than 1000 feet, and at some points more than 2000 feet above 

 the level of the sea. 



These and similar objections are made by those who com- 

 pare the modern effects of igneous and aqueous causes, not with 

 a part but with the whole results of the same agency in ante- 

 cedent ages. Thus viewed in the aggregate, the leading 

 geological features of each district must always appear to be 

 on a colossal scale, just as a large edifice of striking architec- 

 tural beauty seems an effort of superhuman power, until we 

 reflect on the innumerable minute parts of which it is com- 

 posed. A mountain mass, so long as the imagination is occu* 



