494 Notices and Extracts from the Minutes of the Geological Society. 



tween the two seas, the water may be heard gushing beneath. It is, how- 

 ever, remarkable, that in the sandy ridge near this place, water is found near 

 the surface, although further south it cannot be iiad within a hundred fa- 

 thoms. The author then fully describes the navigation, course, rise and fall, 

 and inundations of the Oxus ; and he mentions that it is frequently frozen 

 over. 



The author then notices the effects of the great earthquake of 1832 in the 

 valley of Badakhshan. The roads in this valley were blocked up for several 

 days by the falling of stones and cliffs, and this place seems to have been the 

 centre of the convulsion. Badakhshan is famous for its rubies, which are 

 found imbedded in hmestone. 



The country which extends from the north of the Oxus towards Bokhara 

 (1200 feet above the sea), is next described. It consists of a succession of 

 low ridges of soft, yellowish limestone, sometimes oolitic, with a superficial 

 coating of loose gravel, alternating with plains of hard clay. Sand-hills of 

 greater or less extent, raised by the winds, also occur in several places on this 

 plain, and in some of the valleys are saline rivulets and deposits of salt. 



The author offers some remarks upon the inhabitants, and on the meteoro- 

 logical phasnomena which he observed in the neighbourhood of Bokhara; 

 and concludes his memoir with a description of the sandy desert of the Tur- 

 comans, between the Oxus and the Caspian Sea. 



8. — An attempt to bring under general Geological Laws the relative position 

 of Metalliferous Deposits with regard to the Rock Formations of lohich the 

 Crust of the Earth is formed. By M. Albert Louis Necker, For. Mem. 

 G. S. 



The author commences by remarking, that the rules framed by ancient 

 writers for recognising metalliferous districts by the external configuration 

 of the soil were very fallacious ; and that the laws which guide the miner in 

 discovering new metalliferous veins in one country, will often not assist him 

 in another. He next observes that, as far as he is aware, Werner and his 

 disciples abandoned the idea of establishing a connexion between formations 

 and metalliferous deposits ; and that Button considered the connexion of veins 

 and the rocks through which they pass to be purely fortuitous. He then states 

 that he believes Dr. Boue^ was the first to point out, in a general manner, the 



' Memoire Geologique sur V Allemagne ; Journal de Physique, Mai 1822, tome xciv. p. 297; 

 Geognostisches Gemdlde von Deutschland, p. 139 — 146, Frankfurt, 1829. 



