Rocks of Newton Don. By Kev, George Gunn. 313 



(b.) — Igneous Rocks. 



(I.) On the high walk, parallel to the Eden, is an Altered 

 Andesite, which showed signs of a good deal of crushing by 

 the number of Slickensides or gliding planes to be seen. 



(2) A little further west is an exposure of an Amygdaloidal 

 Scoriaceous Eock, which seems to point to the conclusion that 

 it formed the surface of the lava flow, of which the previous 

 rock was a more central part. 



(3.) The Lynn. The rock here iy a dyke, which seems to 

 have cut its way through the sedimentary rocks. It appears 

 to be part of the mass of igneous rock that crops out on 

 the farm of Baillieknowe, and to the S. and W. of Stitchili 

 Manse. The whole of this mass is characterised by the 

 presence of porphyritic augite crystals, and by curious red 

 veins of ferruginous matter, which run through the rock, and 

 often form a setting to the crystals in the rock. As no 

 Olivine is present, the rock must be regarded as an Altered 

 Augite Andesite. 



