1XX1V NOTES. 



celebrated sulphureous thermal waters issued forth, fire had risen out of the 

 Earth. (See Curtius, Peloponnesos, Bd. i. S. 42 and 56.) On the " indescri- 

 bably sweet smell," which at Santorin (Sept. 1650) followed the sulphureous 

 stench, see Ross, Reisen auf den Griech. Inseln des iigaischen Meeres, Bd. i. 

 S. 196. On the smell of naphtha in the vapours from the lava of the Aleutian 

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

 Bd. ii. S. 106, and Leop. de Buch, Description physique des lies Canaries, 

 p. 458. 



( 3n ) p. 228. The highest summit of the Pyrenees, i. e. the Pic de Nethou 

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

 twice measured trigonometrically, and its height above the sea is 3481 metres 

 (11,420 English feet) according to Reboul, and 3404 metres (11,168 English 

 feet) according to Coraboeuf. It is, therefore, 1705 feet lower than Mont 

 Pelvoux in the French Alps near Brian9on. In the Pyrenees, next after the 

 Pic de Nethou in height come the Pic Posets, or Erist, and, in the group of the 

 Marbore', Mont Perdu and the Cylindre. 



( 312 ) p. 228. Me'moire pour servir a la Description ge'ologique de la France, 

 t. ii. p. 339. Compare on Valleys of Elevation and encircling Ridges in the 

 Silurian Formation, the excellent descriptions of Sir Roderick Murchison in his 

 Silurian System, Pt. I. p. 427442. 



( 313 ) p. 228. Bravais et Martins, Observ. faites au Sommet et au Grand 

 Plateau du Mont Blanc, in the Annuaire Me'te'orol. de la France pour 1850, 

 p. 131. 



(") pi 229. Kosmos, Bd. iv. S. 221 (English edition, p. 172). I have 

 twice visited the volcanoes of the Eifel, at very different stages of the develop- 

 ment of modern geology: in the autumn of 1794, and in August 1845; the 

 first time in the district of the Laacher See, and the then still inhabited Abbey ; 

 and the second time, in the district round Bertrich, the Mosenberg, and the neigh- 

 bouring Maars; each time only for a few days. As, on the last excursion, I had 

 the happiness of accompanying my intimate friend Berghauptmann von Dechen, 

 I have been enabled, by a correspondence of many years, and by the communi- 

 cation of important manuscript memoirs, to avail myself freely of the observa- 

 tions of this clear-sighted geologist. I have often, as is my custom, distinguished, 

 by marks of quotation, passages taken verbally from his communications. 



( 315 ) p. 230. H. von Dechen, Geogn. Uebersicht der Umgegend von Bad 

 Bertrich, 1847, S. 1151. 



( 31fi ) p. 230. Stengel, in Noggerath, Das Gebirge von Rheinland und 

 Westphalen, Bd. i. S. 79, Tafel III. Compare also C. von Oeynhausen's ex- 

 cellent elucidations to his Geogn. Karte des Laacher Sees, 1847, S. 34, 39 und 



