306 Relations of Trap-Bocks with Ores of Copper. 



of rivulets, small rounded pieces of native copper carried 

 down by the running waters. These valuable indications, 

 long neglected on account of the difficulties of the countries, 

 have at length been properly appreciated. A colony of miners 

 is disti'ibuted through numerous stations, and the small vil- 

 lage of Kewena-Point, become the centre of this movement, 

 already possesses a weekly journal, principally intended for 

 the workmen and miners. 



The repositories of Lake Superior extend over a very ex- 

 tensive tract of country, since they are also wrought on the 

 north-west banks, which belong to Canada. Their forms can- 

 not yet be considered as defined, for Mr Jackson'^s description 

 applies only to some particular points ; its extension to the 

 whole metalliferous region would be to exceed the pro- 

 bable facts indicated by analogy. M. de Verneuil returned 

 with the idea that these ores were found principally in the 

 veins which traversed both the traps and upraised sand- 

 stones. These veins are composed of quartz, calcareous 

 spar, prehnite, and laumonite, containing native copper in 

 scales, dendritic, in small plates, and lastly, in lenticular 

 forms and masses, sometimes so large, that, in the mining 

 of one of these veins, it was necessary to construct a spe- 

 cial apparatus for breaking down the copper into transport- 

 able fragments. 



We cannot, therefore, determine whether these ores are con- 

 temporaneous with the trappean masses, or posterior to them ; 

 but there can be no doubt that they are intimately connected 

 with the outgoing of these rocks, and that they constitute 

 an additional example, acquired by science, in favour of 

 the relations which we have pointed out. 



{To he concluded in our next.) 



