35 



tinguished by having the magnetic property, sometimes in a high 

 degree, many masses being found endowed with magnetic polarity 

 in unusual strength. 



Numerous small openings have been made here, at various 

 times, in quest of a regular and solid vein, but, until recently, 

 none promising to be of useful quality and dimensions have been 

 explored. From some excavations lately made the indications 

 seem to be more encouragins:. 



In the Musconetcong Mountain, the appearances of the surface 

 do not justify the hope of there being any considerable veins of 

 the magnetic ore. 



The next and last tract of the primary hills, towards the west, 

 abounding in this valuable mineral is Scott's Mountain, in War- 

 ren county. 



A brief account of the veins in the vicinity of Oxford Furnace, 

 the locality of chief importance in that district, will complete the 

 details which we have to offer upon the subject of the magnetic 

 iron ore of the region. 



Here, as elsewhere, the direction of the veins is parallel with 

 the bearing of the strata of granitoid gneiss which include them. 

 There appear to be at least two principal veins, but the precise 

 thickness of either it is difficult to ascertain, owing to their 

 varying constantly in their dimensions. The quantity of ore, 

 however, is enormously great. The veins are divided here and 

 there, by thin beds of the rock, into several parallel branches, 

 so that the aggregate width of the ore has not been wrought in 

 many places. The adjoining strata are, moreover, considerably 

 disordered, and the veins are, in consequence, throv^'n out of 

 direction by two or three pretty large faults. These are con- 

 nected with detached or broken off portions of the lodes, two of 

 which are known to sweep round a curve of almost semicircular 

 form. 



Some portions of the adjacent strata contain the oxidulated 

 magnetic iron in a crystalline state, disseminated in sensible pro- 

 portions through the rock, or rather through certain layers, either 

 associated with the hornblende or replacing it. 



The greater part of the ore resembles in quality that of the 

 ranges before described, being the magnetic oxide of iron, either 

 compact and massive, or in granular crystallization. It has the 



