124 Outlines of the Mineralogy of the Ochil Hills. {Feb. 



by a streamlet which divides the King's Seat from Craiginnan,* and 

 in "a section ahore the village of VVestertoun, In this district it 

 forms separate hills, or their caps ; and in the central parts of the 

 group it aliernates distinctly stratified with the basaltic clinkstone, 

 which it connects with the felspar rock through the felspar por- 

 phyry. The section above VVestertoun may be considered a beau- 

 tiful epitome of these alternations, and it receives an additional 

 interest frpm its exhibiting a line view of the junctions of the coal- 

 field with the newer rocks. The beds of greenstone have a dip and 

 direction at right angles, to the dip and direction of the clinkstone, 

 from which it is separated by thin seams of decomposing steatite. 

 The beds of the greenstone itself are also separated by thin seams 

 of this steatite, wliich contains considerable quantity of iron pyrites. 

 The gradation t from the rock in which the hornblende predomi- 

 nates to that in which a beautiful flesh-red felspar prevails, is 

 marked in a series of six alternating portions of greenstone and 

 clinkstone, which commence at the above-named section, and may 

 be traced in the face of Bencleugh beyond Alva. 



It is worth recording, that a bed of greenstone occu''s in a coarse 

 conglomerated rock in the hill of Balcanquhal.;}: It is of small 

 extent, and may be seen in all sides except at its base. There can 

 therefore be no doubt of its relations to the rock in which it is 

 imbedded, from the characters of which it may be fairly presumed 

 that it does not owe its existence to volcanic agency. § 



The characters of the greenstone are those which commonly 

 occur, except in the higher alternating beds, where they assume 

 those of the rock which Mr. Jameson calls sienitic greenstone. It 

 is occasionally porphyrytic, containing fine and indistinct crystals of 

 rutilite. 



10. Clay stone Porphyry. — On the south side of the Abernethy 

 Hills a bed of flesh-red claystone porphyr}', with crystals of glassy 

 felspar, is above the clinkstone, and some varieties of greenstone, 

 but its relations are wholly undelined. 



1 1 . Felspar Porphyry — Forms the caps of the highest hills 

 which lie between Dunning and Dunblane. It is a compact flesh- 

 red felspar, containing crystals of white calcareous || spar. In the 

 course of the streamlet which runs past Castle Campbell it alter- 



• Craiginnan is the hill which rises immediately behind Dollar, and is connected 

 by a series of conical hills vi ilh the romantic and precipitous Craig Rossie, which 

 rises to the westward of the village of Dunnin;;, in Perthshire. 



+ It is a curious fact that all the red varieties of rock that I have observed in 

 the Ochils occur at the highest points. It is dilRcult to form even a conjecture ai 

 to the cause of this. 



I About three miles from Kinross, to the north of the road between that plac« 

 and Cupar. 



^ If this bed of greenstone were spouted up from the centre of the earth the 

 intensely hot fluid mass must have acted on the bed through which it flowed. But 

 of this action there is no evidence. 



II This appears to be intimately connected with the sienitic greenstone. Som* 

 beautiful masses of this rock are to be seen hit^her Ihao the greenstone at Craig 

 Kosiie, Dear to Duniiinj;. 



