Br. Mac Culloch on the Geology of Glen Tilt» 315 



the granite, and are found in the bed of the river, do not run to any 

 extent through the mass of strata. It is therefore probable that 

 they are not veins, but simply irregularities, of the granite. 



The junctions of granite in the Tilt are not therefore the transit 

 of independent granite veins like those of Portsoy or Rona, but the 

 interrupted portions of a continued line of junction between a great 

 «Urface of stratified rocks, and an equally extensive but irregular 

 surface of granite. 



Wherever this junction is found, a complicated disturbance of 

 the whole rocks at the point of junction is seen, and sriiall veins of 

 granite are observed penetrating the stratified rocks. 



In these places of junction the granite becomes so intimately 

 mixed with the limestone as to alter its character, and wherever 

 the granite is in contact both with sehi.st and limestone, a similar 

 mixture and transition between those two substances takes place. 



In all other cases the schistose and calcareous rocks preserve both 

 itheir regular disposition and their ordinary chemical characters. 



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