358 GEOLOGY OF THE SECOND DISTRICT. 



addition of particles to certain planes. Changes undoubtedly are taking place continually in 

 the forms of the crystals, inasmuch as they are immersed in a fluid which has some solvent 

 power. The surface often presents the kind of appearance which we observe where alum, 

 or any soluble salt, has been partially dissolved. And again, clusters of crystals appear as 

 though recently formed, being mere skeletons ; though it is not easy to decide whether they 

 are recent and unfinished, or merely crystals which have been partially redissolved. 



Some of the water-courses which were opened during the mining operations, not only con- 

 tained a large amount of water, but it existed under great pressure. One course in particular, 

 when pierced, spouted water between fifty and sixty feet, for two days, in a horizontal direction. 



From the water thus filling a cavity or space, we may reasonably suppose that deposits of 

 particles of carbonate of lime will take place ; but the phenomena will unquestionably vary, 

 and sometimes the water, instead of parting with its soluble matter, will actually act upon 

 and redissolve the calcareous portion of the vein. In truth, we have reason to suppose that 

 tlie state and condition of the materials are constantly changing : at one time, depositing anew 

 upon the faces of crystals already formed ; and at another, redissolving and taking up the solid 

 matter of which they are composed. Without doubt, the electrical state of the interior of a 

 vein has much to do with the physical forms of the bodies contained in it ; and as this state 

 is liable to constant or at least daily variations, some additions to or subtractions from the 

 crystals may be expected. All these changes, according to the discoveries of the most able 

 philosophers, must take place in those materials only which are soluble ; for experiment and 

 observation prove that the electro-magnetic agency or force is confined to bodies which are 

 dissolved in an aqueous or other liquid menstruum. Solid bodies, as well as aeriform ones, 

 remain unaffected by the electro-motive forces. For this reason, the filling of veins by this 

 agent or power is rendered at least doubtful ; although the transference of a single substance 

 to a distant place, and its deposition there, are facts agreeable to experiment and observation. 



The Coal Hill mine is, without doubt, the most important vein which has been discovered 

 in Rossie. A very large amount of lead has been made there. Previous to January, 1838, 

 2,029,415 lbs. had been smelted. The quality of the metal is good, being very soft, and well 

 adapted to the manufacture of white lead. ' 



Victoria Mine. 



The vein which ranks next in importance and size, is the Victoria mine. This is about 

 three-fourths of a mile east of the Coal Hill mine. Its range is S. 84° E. At the depth of 

 forty feet, it is two and a half feet wide. It does not yield so much lead as the vein described 

 above. Its gangue is calcareous spar, but far less crystalline than in the Coal Hill mine. 



This mine strikes across a marsh about eighty rods wide, and then rises upon a high head- 

 land, where it reappears. It is then known in the vicinity by the name of Union mine. The 

 whole width of the mine appears to be greater in this western prolongation, without an increase 

 of lead. It is said, however, to be worked with profit. 



