134 



South America. 



This year is marked by a great accession to our acquaintance 

 Avith Soutli America, by the appearance of the splendidly illus- 

 trated work of M. Alcide d'Orbigny, published at the expense of 

 the French government, and for which geologists have been long 

 waiting with impatience. During eight years of research, this gifted 

 naturalist successively examined the coasts of Brazil, the Republic 

 of Uruguay, the Argentine Republic from the frontiers of Paragviay 

 to Patagonia, the coasts of Chili, Peru and Bolivia ; and by a long 

 residence in the last-named country he was enabled to survey, in 

 many directions, a large region from the coast to the interior. 

 The details of his labovirs form a first part of the work, illus- 

 trated by many sections and by one of most beautifully coloured 

 geological maps which ever fell under my observation. In his ge- 

 neral observations M. d'Orbignj^ remarks, that his own observa- 

 tions extend from 12° to 42° south latitude, and from 45° to 80° 

 longitude west of Paris ; a surface comprised between the coast of 

 the Atlantic Ocean in Patagonia to Lima on the Pacific ; whilst, 

 by collecting the observations of other travellers and examining 

 fossils from more distant localities, his general vievi^s may be said 

 to apply to all the vast continent between Colombia on the north 

 and the Straits of Magellan ! This author reviews in chronological 

 order the different rocks, and indicates each change which they 

 have undergone, describing the granitic, porphyritic and trachytic 

 masses in relation to their extension, composition and elevatory 

 agency- He then considers in an ascending order of date the sedi- 

 mentary deposits, which he classifies as Gneissic or Primary, Silu- 

 rian, Devonian, Triassic, Cretaceous, Tertiary and Diluvial or De- 

 trital; showing the dislocations \vhich they have undergone at 

 successive eiDochs, and the causes of these distui"bances. 



After an enumeration of all the facts, M. d'Orbigny, under the 

 head of conclusions, sketches out all the great revolutions of which 

 South America has been the scene ; a subject on which he seems 

 to display much vigour of thought, but which I cannot now 

 attempt to analyse, without doing injustice to him, not having, in 

 truth, had time to study his work. One only of his inferences I 

 will advert to, as being clearly established by the order of the evi- 

 dences ; viz. that, as the increment of fresh matter has successively 

 taken place from east to west, so the ancient beds of the sea have 

 been heaved up successively on lines trending from north to south, 

 and to the west of that primary, or original nucleus on the Bra- 

 zilian shores. 



Eastern Countries. 



, Jlindostan,Affghanistan and China, — Long as Hindostaji has been 

 attached to the British Empire, vast lacunae remain to be filled up 

 before a general geological map of this peninsula can be published ; 

 and yet, in no part of the earth over which British rule extends, is 

 an adequate acquaintance of the subsoil more required. Viewing 

 it as the great centre of civilization of the East, I should hail the day 



