RANGE OF THE GNEISS. 77 



portant primary mass in the district north of the Moliawk valley. In some places it is very 

 finely cliaracterizcd, particularly at Crane's mountain, and the whole range of the Luzerne 

 and French mountains, and in most of Hamilton county. But in St. Lawrence county, 

 gneiss, granite and primary limestone are frequently blended and mixed in such j)roportions 

 that it is not always easy to designate the mass. . . ' . 



Dip and Strike of the Gneiss. 



In a region which has been subjected to so many disturbing agencies as the northern part 

 of New- York, it will be a matter of no surprise to find the inclination of the rocks varying 

 very much in different places. Such is the fact; yet at the same time tlic strike of the rocks 

 is quite constant, being very nearly in the direction of northwest and northeast tliroughout 

 the whole district. 



By reference to the topography given in the first chapter of this report, it will be seen that a 

 wide belt of highlands traverse the Second District from the southwest to northeast, commen- 

 cing in the valley of the Mohawk, and terminating upon the west shore of Lake Champlain. 

 Regarding those highlands as an uplift, we shall find that there is a general correspondence 

 of the dip to the several slopes which are thus formed. Thus, upon the east and southeast 

 side or slope, the dip of the gneiss is easterly, or to the southeast ; and upon the west, or 

 southwest slope, the dip also corresponds. But this is not true universally, as will be seen 

 from- the following statement : At Crown Point landing, the dip is nearly northwest, while at 

 Bulwagga mountain it is east. At Crag Harbor, near Port Henry, it is west ; three miles 

 west of Clintonville, it is northwest. Near the landing at Port Henry, the dip is northeast ; 

 at the old Crown Point ore bed, it is westerly. At the Hall ore bed in Moriah, it is west ; 

 while at the Sandford ore bed it is northwest, and still farther south it is east ; but four miles 

 west of East Moriah, it is nearly northeast. On the west side of the ranges of highlands in 

 St. LawTcnce county, the dip is not so variable. At Tate's ore bed, the gneiss dips north- 

 west ; in Dekalb northwest, and also in the south part of Canton it is northwest. The change 

 in the direction of the dip is quite common, if not general, at the veins of magnetic o.\ide of 

 iron, which seem to have been connected with the disturbing causes which have so frequently 

 reversed the dip of the strata. The amount of the dip varies also exceedingly ; so much so, 

 that in a general account, it is sufficient to say that it is found from 10° to 90°. Thus, at 

 the great falls at Corinth, the gneiss dips only about 10° to the northeast'; in a great part of 

 the Luzerne mountains, the dip exceeds 50° ; along Bulwagga on the Champlain, it is nearly 

 vertical. 



TTie Mountain flanges composed of Gneiss. 



I had occasion to remark, when speaking of granite, that in the Northern District, it never 

 forms mountain masses, but always occupies the lower parts of the country in which it lies. 

 Gneiss, however, forms some of the highest ranges north of the Mohawk valley, with the 



