Mineralogy of Sky. 187 



where the fine fibrous, granularly schistose, and distinctly crystal- 

 lized, occur together, nor does it, like that one, contain talc. Its 

 analogy to hornblende slate in a geological view is as obvious as is 

 the resemblance of the two minerals, and its passage into that rock 

 is here effected by the addition of crystals of black or greenish horn- 

 blende, which gradually increase in number till the actinolite is 

 entirely excluded. 



I have in another place mentioned the regular north-easterly di- 

 rection of the gneiss, and I think it interesting to remark that the 

 actinolite rock of Glen Elg corresponds with this one, as well in 

 direction as in quality. If a north-east* bearing be taken from it 

 on the map so as to intersect Glen Elg, it will be found to touch a 

 point near Eilan reo'ch, as near to the place of the actinolite rock 

 there situated as it is reasonable to expect from the nature of the 

 map, and I may add that the direction of the gneiss on both sides 

 is correspondent. There is therefore every probability of its being 

 a prolongation of the same bed, but to what further extent it may 

 be traced is beyond the bounds of this investigation to enquire. 

 The total distance included between the two points is about seven 

 miles. 



In formerly enumerating the members of the zeolite family which 

 are to be found in Sky I mentioned laumonite on the authority of 

 others, although I do not know the name of the individual to whom 

 the discovery is attributed. Since that period I have myself found 

 it in the same place between Loch Eynort and Loch Brittle in 

 which the decomposing stilbite formerly described is to be seen. 



* Allowing 24° for the variation of the needle, the bearing of this bed appears to be 

 north-east by east, but as the variation on this coast is not at present accurately known, 

 as no examination of local irregularities has been instituted, and as the maps themselves 

 are erroneously laid down, I have in this as in other instances held it fruitless to state 

 their beirings with rigid accuracy. 



