238 THE MEDITERRANEAN SEA. 



Neptunian Mountains of Sicily ; and beyond this by a bar or 

 line of shallow sea, occupying the strait between Sicily and 

 Africa, and separating the profound depths which lie on each 

 side of this submarine ridge. Though a part of the line be 

 thus submerged here, as well as in the narrower breach 

 forming the Strait of Messina, the physical fact is even 

 rendered more striking by this submergence ; and brought 

 more closely into relation with those geological changes 

 which have moulded the surface into its present shape and 

 aspects. And that great subterranean forces have actually 

 been at work in this barrier line, we have evidence equally 

 curious and instructive, in the volcanic phenomena, present 

 as well as extinct, which are notable throughout its whole 

 extent; not uninterruptedly indeed, but so connected in 

 proximity and direction as to give them an evident relation 

 to a common physical cause. At the northern end of the 

 line we find the volcanic rocks of the Euganean Hills ; amidst 

 which, in the village of Arqua, stands the secluded tomb of 

 Petrarch. Coming southwards, a long tract of extinct vol- 

 canic formations stretches through the Eoman States. Yet 

 again, farther south, lies the region of Vesuvius and the Campi 

 Flegrei ; wonderful in its present phenomena, and not less 

 so in those which belong to ages anteceding any known 

 history. Following the line farther, we come to Stromboli 

 and the Lipari Isles, still emitting flames and volcanic 

 vapours, as they are recorded to have done more than 2,000 

 years ago. Yet farther south, but within sight of these isles, 

 rises the mighty cone of Etna, circled round by a vast girdle 

 of lavas and other volcanic rocks the theme of magnificent 

 poetry to early times, and in the series and succession of 

 these rocks giving record of ages far anterior to any poetry 

 on earth. The line of subterranean fire we are tracing has 

 still another attestation in an event of our own days. In 

 1831 a volcano suddenly burst forth in the mid-sea between 



