and some other Stratified Deposits in the North of Scotland. 307 



an associated limestone have been derived from the slate of Caithness,, which 

 is very largely developed to the north of the Ord ; but such an inference can 

 hardly be admitted, since the latter alternates with the sandstone of the red 

 conglomerate, elsewhere shown to be composed of those granitic and older 

 rocks, of which latter there is not a vestige in this singular breccia. 



The beds of limestone near the Ord have also an altered character. They 

 are very compact, of a semi-crystalline structure, void of fossils, much 

 charged with ferruginous matter, highly elevated, and traversed by veins of 

 crystallized carbonate of lime. 



Here the cliff is generally from 80 to 120 feet in height, divided by nume- 

 rous ravines, in the bottoms of which the granitic rock is disclosed by the 

 streams flowing from the mountains of the interior. Irregular conical masses, 

 chiefly consisting of a highly ferruginized cellular sandstone, in which all 

 traces of stratification are lost, stand up in the mouths of these narrow defiles. 



These are terminated by a peninsulated terrace, called the " green table," 

 which serves as a pedestal to the Ord of Caithness ; and, at its base, the breccia 

 rising from the sea with a rapid inclination, forms an admirable breakwater 

 against the waves of the German Ocean, to the violence of which this promon- 

 tory is fully exposed. (See Section, PI. XXXI. fig. 2.) 



It has been frequently remarked that, wherever the granitic rock appears, 

 the beds in contact with it are elevated, and, in many instances, shattered into 

 fragments : hence it would seem that such phaenomena can only be explained 

 by supposing the former to have been thrown up at periods subsequent to the 

 deposition of the latter. 



East Coast of Ross and Cromarty. 



I could discover no portions of the oolitic series to the north of the Ord of 

 Caithness ; and, to the south of the district described, the low coasts of Su- 

 therland and Ross are composed exclusively of the sandstone of the red con- 

 glomerate, occasionally accompanied by a lamellar sub-crystalline limestone. 

 My attention, however, was directed by Sir George Mackenzie to certain beds 

 with fossils which occur near those remarkable headlands the Sutors of Cro- 

 marty. 



At the northern extremity of a narrow mountainous ridge which there occu- 

 pies the coast, the red conglomerate rises from its horizontal position in the 

 plain of Easter Ross *, where it is for the most part in the state of a fine-grained 

 sandstone, and, sweUing into hills which bound Shandwick Bay upon the south, 



* These plains of Easter Ross are celebrated for their fertility and abundant production of 

 wheat. This agricultural distinction is very remarkable in so northern a latitude, and affords a 



