608 



Mr. J. Beete Jukes and the Rev. Samuel Haughton on the 



Over a large part of the district there are a number of outlying granitic 

 patches, occupying a well-marked and characteiistic position. These form a 

 series of long granitic islands, following rather the strike or bearing of the beds 

 than the geological boundary of the granite axis, and suggest the idea, which 

 may be collected from the map, that the true axis of the granitic chain lies 

 more to the east of north than would appear from the line of its separation from 

 the slate. 



It is impossible to discuss the mineral composition ofthese outlying granitic 

 patches by the same systematic method that we have applied to the main gra- 

 nite chain itself, as we have the best reasons for believing that they are all 

 formed of that granite, adulterated and mixed with bases, which, varying from 

 place to place, alter the character of the rock in a manner that never occurs in 

 the main chain. We look upon that as the great molten mass, of which the 

 granite islands are offshoots, more or less affected by the bases they have 

 fallen in with in their contact with the slate rocks. The truth of this remark 

 will be best seen from the analyses in the following Table, in which the loca- 

 lities are arranged in order of occurrence, from N. W. t-o S. E. : — 



2. — Chemical Composition of the Outlying Granitic Tracts. 



Table XII. 

 Composition of the Outlying Granitic Rocks. 



