368 MEMOIR OF LEOPOLD VON lillCH. 



all associated, (soUdairesj aud one uever commences until the otlier has ceased. 

 As, in hands so skilful, the thread of analogy, once seized, is never broken, 

 from the volcanoes of the Canaries he passes to those of the entire globe, 

 and ranges them all under two classes, central volcanoes aud volcanic chains. 

 The first form the centre of a number of eruptions which take place around 

 them ; the second are all disposed in line, each following the other in the same 

 direction, like a great rent or fissure of the globe ; being, as Von Buch adds, 

 probably nothing else but such a rent. From these isolated points of rock, 

 elevated by fire, transporting his view over the innumerable isles everywhere 

 scattered in the ocean, he combines them all under the generic name of isles 

 of elevation, thus dispelliug the opinion which long regarded the former as the 

 relics of a submerged continent. 



Scarcely had he returned from the Canaries (about 1819) when some inquiry 

 led him to the Hebrides, whose basalts formed the object of his visit, and thus 

 the giant's causeway became the route which reconducted him to Germany. 

 There, a new problem hurries him to Paris ; and though it is the midst of win- 

 ter, and a bruised arm, the result of his precipitation, threatens to detain him, 

 he takes with him a young relative, and this time travels post, for his impa- 

 tience is extreme. " If," said he, " Humboldt should have quitted Paris, the 

 great city would seem a desert to me." He arrives, however, in season, and 

 the two friends meet ; but how is time to be found for long conversations ? All 

 the saloons are emulous of Humboldt's presence. The interviews, however, 

 take place regularly, only they commence at midnight and do not terminate 

 until morning. 



This strain of scientific excitement, added to the cold, renders Von Buch 

 really ill. M.-d'Arnim,* his young relative, hazards some expressions of 

 blame. " True, it is my own fault," replies the culprit, " the fire of the chim- 

 ney near which we were talking had gone out and I felt chilled ; but by making 

 a movement to rekindle it I should have perhaps hastened Humboldt's depar- 

 ture. I preferred suffering to being deprived of his conversation, aud am 

 Avell content, for I have gained much by it." 



Hitherto Von Buch had presented his leading idea of the upheaval of 

 mountains with the reserve distinctive of the conscientious though bold in- 

 quirer. In 1822, after a new exploration of the south Tyrol, he shows him- 

 self more decided, and in a letter to Humboldt, on that country, has giA'cn us his 

 ultimate determination in regard to those great and hazardous questions. Here 

 he pronounces, with an authority which no one as yet had acquired on this 

 subject, that all the projecting masses on our globe owe their present position 

 to an actual upheaval.! In this he finds an explanation of the fact, till then 

 inexplicable, that marine shells occur on the summits of the highest mountains ; 

 not that the seas have risen to those summits,| it is the mountains which have 

 been raised from the bottom of the seas. Never had a graver difliculty, nor 

 one which longer resisted the efforts of ingenious minds, been solved in a sim- 



* I am indebted to M. d'Arnim for most of the private traits of character g'iven in this nar- 

 rative. 



t " The pyroxenic porphyries of Fassa owe their actual position to an iipheaval. But we 

 must carefully observe that it is not the particuhar elevation of a rock which is in question, 

 but the lifting rrp of the whole mass of mountains, and consequently of the entire country." — 

 Letter to M. dc Humboldt, &c. "It is now many years since I entertained a doubt that the 

 whole chain of the Alps — at least the calcareous Alps — owed its elevation to the pyroxenic for- 

 mation. • This formation breaks the strata which oppose its egress. It pierces or upheaves 

 fii\st the red porphyries, then the sandstones, then the calcareous strata." — Ibid. 



t "Reflecting on the effects of these upheavals, we shall be less sui-{nised at meeting 

 with petrifactions of anomia' in the sandstones and calcareous strata at the height of nearly 

 8,000 ieet above the Sasso di Val Fredda. These same petrifactions, which are found at 

 .5,400 feet above the passage of the Caressa, 3,800 feet above Seiss, "2,600 feet above Saint 

 Paul and C'altern, were, perhaps, before the catastrophe of the upheaval, situated lower than 

 the level of the seas." — Letter to M. de Huviboldt. 



