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pressure, and the deformation may have been effected by the 

 slow flowing of particle over particle. The change in form 

 may, however, have been brought about by the slow process 

 of solution and reprecipitation ; if this be so it would 

 indicate the existence of slow folding processes extending 

 over a long period of time. The contorted broken quartz 

 of some belts suggests that in some places the motion was 

 too rapid to admit of the veins maintaining their conti- 

 nuity either by flow or by solution and reprecipitation. 



The origin of some of the small crenulations which are 

 often observed in many interstratified veins and in a few 

 cross veins having a thickness less than one inch, is probably 

 due to a slight motion along the numerous cleavage planes 

 during the folding process at stages subsequent to the 

 deposition of the veins, for these crenulations are often 

 found to coincide with the intersection of the cleavage 

 with the bedding plane. It is also possible that some of 

 the larger corrugations are the result of the combined 

 motion of the slate beds from the limbs towards the apex 

 and that of the wall-rock along the cleavage planes. 



The bulk of the evidence shows that the veins were 

 filled by ascending solutions of a deep-seated origin. 

 These found a passage upward through the fractured 

 portions of the domes. A fracturing across the bedding 

 as well as Assuring along the bedding planes seems to have 

 been necessary for the formation of veins and ore deposits: 

 veins are not commonly found along straight non-pitching 

 anticlines although there was, no doubt, a great deal of 

 Assuring along the bedding planes; on the other hand, 

 where the anticlines pitch and the rocks were fractured 

 across the bedding, veins are abundant. The cross 

 fractures are themselves filled with quartz forming the 

 angulars entering and leaving the interbedded veins. 

 The cross fractures seem therefore, to have provided 

 channels for the passage of solutions across the beds 

 of quartzite and slate to the interbedded fissures along 

 which deposition took place. That the solutions entered 

 by way of the angulars is borne out by the fact that the 

 rich portions of interbedded veins are those portions 

 lying between the line of entrance of an angular and the 

 line along which it leaves the main lead. 



The source of the ascending solutions is not known, 

 but it is held not to be in the granite or any other known 

 igneous intrusion. Field evidence goes to show that the 



