233 COSMOS. 



indications of naphtha ? The same thing is also referred to 

 by Kotzebue, in his Russian voyage of discovery, in connec- 

 tion with an igneous eruption (1804) of the volcanic island of 

 Umnack, newly elevated from the sea in the Aleutian Archi- 

 pelago. During the great eruption of Vesuvius, on the 12th 

 August, 1805, which I observed in company with Gay- 

 Lussac, the latter found a bituminous odour prevailing at 

 times in the ignited crater. I bring together these little- 

 noticed facts, because they contribute to confirm the close 

 concatenation of all manifestations of volcanic activity, the 

 intimate connection of the weak salses and naphtha springs 

 with the true volcanoes. 



Circumvallations, analogous to those of the craters of ele- 

 vafcion, also present themselves in rocks which are very 

 different from trachyte, basalt and porphyritic schists, for 

 example according to Elie de Beaumont's acute observation, 

 in the granite of the French Alps. The mountain mass of 

 Oisans, to which the highest 87 summit of France, Mont 

 name. In the middle of the strait, united with Calauria by a low cause- 

 way, probably of artificial origin, lies a small conical islet, comparable 

 in form to an egg cut through the middle. It is volcanic throughout, 

 consisting of greyish yellow and yellowish red trachyte, mixed with 

 eruptions of lava and scoriae, and is almost entirely destitute of vege- 

 tation. Upon this islet stands the present town of Poros, on the place 

 of the ancient Calauria. The formation of the islet is exactly similar 

 to that of the more recent volcanic islands in the Bay of Thera (Santo- 

 rino). In his animated description, Ovid has probably followed a 

 Greek original or an old tradition" (Ludw. Eoss, in a letter to me dated 

 November, 1845). As a member of the French scientific expedition, 

 Virlet has set up the opinion that the volcanic upheaval may have been 

 only a subsequent increase of the trachytic mass of the peninsula of 

 Methana. This increase occurs in the north-west extremity of the 

 peninsula, where the black burnt rock, called Kammeni-petra, resem- 

 bling the Kammeni, near Santorin, betrays a more recent origin. Pau- 

 sanias communicates the tradition of the inhabitants of Methana, that, 

 on the north coast, before the now celebrated sulphurous springs burst 

 forth, fire rose out of the earth (see Curtius, Pelopwinesos, Bd. i, s. 42 

 and 46). On the " indescribable pleasant odour" which followed the 

 stinking sulphurous odour, near Santorino (Sept. 3650), see Ross, 

 Reisen auf den griech. Inseln des agaiscken Meeres, Bd. i, s. 196. Upon 

 the odour of naphtha in the fumes of the lava of the Aleutian island 

 Umnack, which appeared in 1796, see Kotzebue's Entdeckungs-Reise, 

 Bd. ii, s. 106, and Leopold de Buch, Description phys. des lies Canaries, 

 p. 458. 



87 The highest summit of the Pyrenees, that is, the Pic de Nethou 

 (the eastern and highest peak of the Maladetta or Malahita group), has 



