12 /. C. Ward — Beveloyment of Land. 



A section across the peninsula in about the latitude of Eome would 

 exhibit somewhat of the following structure, seen in Fig. 1, where 

 the Jurassic, which are the oldest rocks of the country, form the 

 nucleus of the Apennine chain, and the Cretaceous and Eocene lie 

 on their flanks, with some minor patches left on or near the summit, 

 while rocks of Miocene and Pliocene age form the low-lying tracts 

 of land between the base of the mountains and the sea. The 

 central mass of Jurassic rocks stretches along the median line of the 

 peninsula from a point east of Naples to one some way south of 

 Florence, and south and north of these respective points it is 

 wrapped round by a narrow framework of Cretaceous rocks, and 

 then by those of Eocene age, which last continue the ridge of the 

 Apennines onward to a little east of Genoa, 



The history of Italy, so far as can be deduced from these stony 

 records, seems not to go back further than the Jurassic period ; ^ and 

 the first decided production of land of which we have any know- 

 ledge occurred not until the close of the Middle Eocene.^ Then it 

 was that this great thickness of strata, which had been accumu- 

 lating for so long, was slowly upheaved along a line which now 

 constitutes the chain of the Apennines in Southern Italy and great 

 part of the Alps in Northern. The elevation, accompanied by con- 

 tortion of the strata, was gradual, so as to allow of an enormous 

 denudation of Eocene and Cretaceous rocks, which over a consider- 

 able part of the elevated area were, with the exception of minor 

 patches, entirely swept away, thus exposing the Jurassic rocks at 

 the surface. This denudation, therefore, deprived the slowly-rising 

 land of much of its height ; and had the elevation taken place rapidly, 

 the present range of the Apennines might have been twice or more 

 as lofty as it is at present. 



The geography of Italy at about the close of the Eocene and com- 

 mencement of the Miocene period must have presented somewhat 

 the form shown in Fig. 2, where the dotted line shows the present 

 contour, and the shaded part the then existing land. 



In the seas around this land were deposited strata, first of 

 Miocene, then of Pliocene age ; but it would seem as if that force, 

 which had before been manifesting itself in producing a slow up- 

 heaval of the ocean's bed, being able to produce no further effect in 

 that direction, now broke fairly through the solid crust in several 

 points, and gave rise to the phenomena of volcanoes.^ The Vicentine 

 and the Euganean Hills, near Padua, are formed of volcanic rocks 

 interstratified with deposits of Pliocene age; and by some of the 

 eruptions in the seas of this period great numbers of fish were 

 suddenly destroyed and preserved in calcareous ash. 



1 Rocks of Silurian age occur in Sardinia., according to General della Marmora 

 (Voyage en Sardaigne). 



^ There may have heen some minor upheavals, producing local unconformities in 

 the several groups of strata. 



' In Sardinia are evidences of volcanic eruption in Miocene times ; and very 

 probably some of the eruptive rocks of the neighbourhood of Genoa date from this 

 period. 



