■10 GEOLOGICAL MEMOIRS. 



practical value of these theoretical laws, as giving sure indications of 

 the presence of useful minerals. Thus, for example, the whole of 

 that portion of Saxony which is traversed by porphyritic veins may, 

 with good reason, be supposed to be more or less metalliferous. The 

 existence of an extensive coal-basin beneath the porphyry between 

 Grimma and Rochlitz is very probable, and even the porphyritic rocks 

 of the Tharand Forest and of Meissen may be presumed to be con- 

 nected with carboniferous deposits. 



From the distribution of metalliferous veins in Saxony the author 

 passes to their distribution through the whole of Europe. He distin- 

 guishes three principal metalliferous zones, following in their general 

 direction the Erzgebirge and Sudetian lines. The first of these zones 

 runs from the shore of the Black Sea in Bessarabia, through Mol- 

 da\da, Bukowina (East Gallicia), North Hungary, Upper Silesia, 

 Saxony, the Hartz, the Teutoburg Forest, and, beyond the English 

 Channel, through the extensive lead-districts of Derbyshire and 

 Cumberland. The second seems to begin on the shores of the 

 Atlantic near Lisbon, and passes across Spain, Southern France, 

 Upper Italy, Ulyria, Carinthia, Banat, and Transylvania. If this 

 direction be correct, it must intersect the first line in the Caucasus ; 

 and this group of mountains may then be supposed to contain an 

 enormous store of metalliferous minerals. This supposition is in 

 some measure supported by the observations of M. Czarnotta, an 

 Austrian mining-officer in the Persian service, who describes the 

 Zend mountains near Tabriz as being uncommonly metalliferous, 

 and the chain between Sultania and Kasbin as being a continuous 

 and enormous mass of iron-ore. The third zone, of a breadth of 

 eighty to ninety German (about 400 English) miles, begins in North- 

 west Spain, passes through Bretagne, the smaller Channel Islands, 

 South Belgium, Nassau, Westphalia, the Erzgebirge, and the Hunds- 

 druck, and intersects the first zone very near the metalliferous di- 

 stricts of Saxony. 



Baron de Beust concludes by pointing out the curious circum- 

 stance of the Saxon stanniferous zone lying in the same straight line 

 with the tin-deposits of Limoges and of North-west Spain, in the 

 same manner as a line drawn through the quicksilver-deposits of 

 Spain and Tuscany, if lengthened, will pass through Idria, and 

 end in the veins of mercurial grey copper in Upper Hungary. 



Haidinger noticed in 1849 an analogous circumstance with regard 

 to boracic acid ; all the localities where this acid is found, either 

 free or combined with basic substances (forming Sassoline, Boracite, 

 and Latolite), being situated along the same north and south line, 

 traceable from the Isle of Vulcano (Lipari Islands) to Arendal in 

 Norway, and sending a westerly branch from Arendal, through 

 Utoen, to Salisbury Crag, near Edinburgh. 



[Count M.] 



