1856.] HARKNESS PERMIAN ROCKS OF SCOTLAND. 263 



presented to us. As regards the thickness of the sandstones, there 

 are more than 200 feet exposed in the Water of Ayr ; and the por- 

 tion of the breccias which is seen must be nearly 50 feet in thickness. 

 The newer strata here exposed appear to me to be most probably the 

 representatives of the low breccias and overlying sandstones of the 

 typical area. Corncockle. 



Sandstone-area of Dumfries. — We have now to return to the area 

 already described*, — the Dumfries area; not for the purpose of 

 alluding to it in detail, but to endeavour to find out its relation to the 

 several patches which have been noticed. In the memoir referred to, 

 the Locharbrigs quarries are noticed {loc. cit. p. 391). These are 

 the quarries which are nearest to the Corncockle quarry ; and some 

 of the strata seen in them are identical with those at the latter 

 locality, afford the same chelonian footsteps, and have even the same 

 angle of dip and direction. Like the Corncockle strata, they have 

 no breccias covering them, and any person examining the two localities 

 would arrive at the conclusion that they are the same, not only in 

 nature, but position. We have in the Dumfries area no exposures 

 of the beds which are subjacent to these sandstones, and consequently 

 the breccias which support these are not seen. 



If the sandstones of the Corncockle quarry and the Locharbrigs 

 strata are the same (which I believe to be the case), then we become 

 possessed of a clue which enables us to judge of the connexion ex- 

 isting between the other beds of the Dumfries patch and those already 

 alluded to. 



The Craigs quarry, south-east from Dumfries, is in the line of the 

 strike of the Locharbrigs sandstones. It is similar in its nature, and 

 it affords the same footprints. As we go from Locharbrigs to this 

 quarry, the breccias come on, and are well seen occupying a position 

 above the sandstone at Craigs (see Section, fig. 5, p. 264) ; and, conse- 

 quently, we have in some portions of the Dumfries area certain breccias 

 which have no equivalents occupying the same relative positions in 

 any of the other Dumfriesshire areas, nor in that of Mauchline in 

 Ayrshire. 



These higher breccias differ from the lower ones in their nature ; — 

 they have fewer beds of sandstone interstratified in them, and they 

 are much harder in their composition than the inferior breccias. 



It is by no means improbable that the hard flagstones of Temp- 

 land quarry, which overlie the beds of Corncockle quarry, may be 

 the equivalents of the lower portion of the Craigs breccias, which 

 are fully described in the memoir above referred tof. If such be 

 the case, and if the sandstones of Locharbrigs, Craigs, and other 

 localities in the Dumfries area be the equivalents of the beds at 

 the Corncockle quarry, then it follows that the sandstones and 

 breccias newer than the Carboniferous formation can be divided into 

 four distinct groups ; — 1st, and lowest, breccias and sandstones, best 

 seen in the course of the Kinnel Water and at Ballochmoyle in Ayr- 

 shire ; 2nd, sandstones, for the most part false-bedded, well seen in 



* Quart. Journ. Geol. Soc, vol. vi. p. 389. 

 t Loc. cit. p. 394. 



