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DESCRIPTION OF TINTO. 



north-east, to the extremity of Scotland on the 

 south-west, the great mass of the Tweddale hills 

 in the vicinity of Tinto, seems to be composed. 



The substance which lies immediately over it, 

 in the body of the mountain we are describing, 

 is a conglomerate, having a basis of clay, with a 

 dark greyish colour, and somewhat resembling an 

 intimately mixed greenstone. The fragments it 

 contains, are from the size of a grain, to that of 

 large balls ; and consist of rounded or water- worn 

 masses of transition rocks, such as grey-wacke, 

 grey-wacke-slate, iron-clay, and common flinty- 

 slate, with veins of quartz. There are also frag* 

 ments or nodules of quartz, mica, felspar, splin- 

 tery hornstone, and felspar passing|into conchoidal 

 hornstone. 



This conglomerate, I conceive, forms the base 

 of Tinto ; as it is found, either in situ^ or in the 

 form of debris, at various places around the lower 

 part of the hill, particularly on the south side, a 

 little above the old ruin opposite to Lamington. 

 Where the rock becomes finer grained, as on the 

 north side, it exhibits scales of mica, and both in 

 appearance and in composition, bears a strong re- 

 semblance in some places to grey-wacke, and in 

 others, to those portions of the old red sandstone 

 which are conjectured to alternate with the newer 

 members of the transition series. It is therefore 

 probable, that, were the base of the mountain laid 

 bare, we should discover indications of what is 



