SALMON — OX THE FORMATION OF ORE-YEINS. 



359 



not identical. The latter is applied to all ore-containing deposits, 

 whether the ore be in rock-veins, mineral-veins, beds, stocks, or 

 irregular and nndefinable masses ; while the term mineral- vein is 

 always used 'v\T.thin the strict hmits of the definition. 



V. The study of mineral- veins has a geological interest in no -s^-ise 

 depending on those veins containing ores ; and the study of the dis- 

 tribution of the ores of the useful metals, in whatever form they may 

 occur, has a scientific interest quite distinct, and of a different class, 

 from that of mineral- veins. The study of mineral- veins, and ^ the 

 study of metalliferous deposits, are consequently not identical pur- 

 suits ; yet they are very nearly allied, inasmuch as by far the greater 

 mass of metalliferous or ore deposits do occm' in mineral- veins. 



General Considerations on the Formation of Ore-Yeins. From 

 the German of Bernhard Cotta, Professor of Geognosy at the 

 Mining Academy of Freiberg.* 



The formation of ore-veins should not, in any case, be regarded as 

 an isolated phenomenon ; it is intimately connected Avith the forma- 

 tion or metamorphism of certain rocks, and is' only a j)articular, or 

 special, effect of certain geological causes. 



It was a ver}^ general and not unnatm^al mistake of the early in- 

 vestigators in the modern school of special geology that, freed fi'om 

 the general and vagnie hypotheses on the formation of the earth pre- 

 valent in the past century, and having their attention concentrated 

 on the observation of isolated geological phenomena, they should 

 consider and endeavour to account for them as being independent 

 of each other and without any necessary connection. The explana- 

 tion discovered or devised to account for one particular case was be- 

 lieved to be applicable to all others in any measure analogous to it. 

 The consequences were, on the one side, too sharp a separation of 

 special branches, and on the other, too gTeat a striving after large 

 generalizations. As they endeavoured to explain the origin of one 

 ore-vein without reference to the incidents of its particular locality, 

 so they would have it that all ore-veins, without distinction, 

 originated in a similar manner. Indeed, some of the latest and 



* Gangstudien, Vol. I., p. 85. 



