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Minerdloglcal Jounicy. 131 



of several hundred feet, and io the depth of fifty feet. Throughout 

 its course thus fai', it has consisted of very excellent ore j d)oiigh its 

 width has rarely exceeded three feet. A few rods higher up tlie 

 mountain, what appears to be the same vein is now working hy a 

 perpendicular shaft, sixty or seventy feet in length, by fifteen or 

 twenty wide ; and which is already sunk to the depth of upwards of 

 forty feet. The ore here does not seem to follow any regular course ; 

 but occurs in bunches throughout the veinstone, which consists princi- 

 pally of garnet- One of them, encountered not long ago, measured eight 

 feet in diameter ; but at present it is uncommon to meet with masses 

 above one foot m diameter. Still another vein is wrought ten or fif- 

 teen rods to tlie north, whose veinstone is mostly epidote and horn- 

 blende. Its ore Is said to yield bar iron with more facility than that 

 of the other workings. No perceptible difference, however, is dis- 

 cernible in the ores j and if there is no mistake upon this point, 

 it may perhaps be accounted for in tlie different nature of the vein- 

 stone, from which the ore is never wholly freed in the process of 

 picking. The ore of tliis place possesses some j>€culiarities when 

 compared with that of other mines in our country. It is remarkably 

 uncrystalline and compact ; but breaks wdth the slightest blow of 

 the hammer into rhombic prisms of from 100^ to 120^, whose faces 

 offer a glimmering, steel-like lustre. This cleavage, which no doubt 

 depends upon the appropriate structure of the species, is of great 

 importance both in the operation of mining, and in that of preparing 

 the ore for the furnace. Indeed, so strong is it, that the simple pro- 

 cess of heating the ore in heaps over a fire of charcoal in the open 

 aii'5 Js sufficient to produce its separation in these directions j which 

 materially assists in its subsequent reduction in the crushing mill. 

 The only perfect crystals of it, which we observed, were a few 

 of the dodecahedral form, imbedded in the compact epidote, so 

 abundant as the veinstone of the most northerly excavation. These, 

 as usual, were deeply striated in the direction of the longer diagonals 

 <^f tlie rhombic planes. About the opening of the same vein, we 

 found a few specimens of Specular Iron ore^ in broad, brilL'ant, in- 

 terlacing plates, presenting upon their edges the beautiful tarnish com- 

 mon to this species. They occupied veins in the gneiss, and were 

 invested by calcareous spar. Crystals of Iron Pyrites, also, under 

 several of its most common forms exists at the same place. 



Leaving for the present, all farther notice of the ores of Iron, I pro- 

 ceed to describe those accompanying substances from which this spot 



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