1846.] Copper Mines. 67 



The Mingan islands are limestone, and so also is Anticosti; they 

 have a southerly dip. From the list of fossils which Capt. Bay- 

 field gives, we have no doubt but that the series of limestone at 

 the Mingan and Anticosti islands extends upwards so as to 

 embrace the Onondaga limestone. We have seen a mass of 

 limestone from Anticosti, which could not be distinguished from 

 the pentamerus limestone of the Helderberg. 



From the Mingan islands to the straits of Belle Isle, the coast 

 of Labrador consists exclusively of primary rocks, but on the east 

 side a sandstone is met w'ith, which passes into gneiss. It ex- 

 tends thirty miles along the northern shore of the straits of Belle 

 Isle, and forms table lands 400 to 500 feet high. This sandstone 

 is undoubtedly our Potsdam sandstone. On the Newfoundland 

 side the limestones which w^e have already referred to occur 

 again. 



We have now occupied so much space upon these geological 

 details, that we deem it inexpedient to follow Capt. Bayfield in 

 his description of the rocks of Canada, in the Gaspe district. It is, 

 however, interesting to us to find the succession of the rocks so 

 much like New York. We see in all these facts, the uniformity of 

 the operation of nature ; the rocks themselves, as W' ell as the phe- 

 nomena accompanying them, are the same as on our own borders. 

 Besides, it is useful to know the great American ranges, and be 

 able to compare them with what falls under our own observation 

 at home — we can say more than this — that it is astonishing that 

 we can trace one series of rocks, abounding in the same organic 

 bodies, for thousands of miles. It is true, that the characters are 

 not absolutely uniform — but any geologist, w^th only ordinary 

 opportunities for observation, can determine the position of almost 

 any rock, provided he is supplied w4th some of its fossils. The 

 application of this kind of knowledge to the determination of the 

 position and age of rocks, constituted an era in geology — and it 

 has been, in the hands of the w^ell taught geologist, a key to the 

 solution of some of the most important questions in this depart- 

 ment of science. 



