198 Mining Report JYo. 1. [Nov., 



Admitting then, that there is ore in an accessible position, how 

 shall it be reached? On this point wc are prepared to say that a 

 tunnel or adit should be driven into the hill, on its eastern slope, 

 close up to the north side of the valley. As the rock is gneiss, 

 ■vve would propose following up the 27 foot dyke which runs east, 

 and is found at least 150 feet below where the shaft is sunk in it 

 at D. The dyke is easily mined, drills easily, and upon the whole 

 is the most feasible rock to work, while its direction is in the line 

 of the most important point of the vein. The dyke can be tunnel- 

 ed for $b per foot linear measure, with an opening 6 feet high, 

 and 5 wide. If the dyke is tunneled as proposed, it will be ne- 

 cessary to carry it entirely upon one side, so as not to miss, or 

 pass the vein, for it never happens that a particle of the ore is 

 carried into the dyke. Hence if it were mined in its centre, the 

 ore would be passed unperceived. 



Another mode of working the mine would be to carry the shaft 

 in the same dyke, or by its side deeper, and then work to the east 

 and west until the miner obtained the vein. 



Upon the whole, and in conclusion, we remark that this mine 

 is quite remarkable for its irregularities. The most interesting 

 enquiry, and what we are anxious to know, is whether this vein 

 would assume the common dip to the west, or whether it is really 

 as we have supposed a single vein which has been folded upon 

 itself. The tunneling and farther working of it as has been pro- 

 posed we expect will decide those points. 



AMERICAN ASSOCIATION OF GEOLOGISTS AND 

 NATURALISTS. 



[Continued from p. 319.] 



Afternoon Session, "Wednesday, Sept. 22, 1847."^ 



Prof. Horsford read a paper to show that the group of alkaline 

 earths are in their intensity in the order of their atomic weights: 

 which are barium 68.6; strontium 43.8: calcium 20.1; magnesia 

 12.8. 



On the Jintiquity of the Western Mounds, hy Mr. Squier. 



These earth-works have been supposed by some to be the results 

 of diluvial agency, especially as some are stratified : but most of 

 them are of artificial origin. 



There are several varieties ; the sepulchral ; those connected 

 with military achievements; and the sacred. 



The sepulchral are isolated. The sacred are smaller, always in 

 an enclosure, and stratified. The outer layer consists of pebbles 



