1814.] Mmeralogical Olservalinns in Gallmvay. 421 



Roturning towards Newgalloway I took two or three more iTcar- 

 ings of the strata on the north-west side of the granite district, 

 which terminates on that qiK^itcr in a high round-topped mountain 

 called Blackcraig, 1 found them all to he directed ahout E. N. E. 

 dip 35° westerly. It appears tlicn that the stratiiied rock all around 

 the northern half of this granite mass has the direction of its 

 strata very nearly the same. It varies only six points, viz. from 

 E. N. E. to N. by H In one case, as I mentioned, I found the 

 direction three points more easterly than any other 1 hud seen, but 

 this was distant from the granite. It appears, also, that on the 

 east side of the granite mass the strata di]) easterly, and on the 

 west side westerly ; or in both eases away from the granite. But 

 on the north-eastern side of this mass the ends of the strata run 

 directly towards it. 



There is ia this district of country, that namely called Glen- 

 kens, which is the valley of the Ken from the borders of /iyre- 

 sliire towards Dahncllington, down part of the Louran, a remark- 

 able change in the dip of the strata. All about Newgalloway, 

 and, as far as I had the opportunity of seeing, towards Newton 

 Stewart on the western side of the granite mass, the dip is north- 

 westerly; but after we pass Carsphavin, which is about 13 miles 

 N. W. by E. from Newgalloway, the dip of the transition strata 

 changes, and all along from thence to the junction of these with 

 the sandstone country of Ayroshirc, 10 miles farther on, and 

 within two miles and a half of Dalmellington, dips south-eastward. 

 In Glenmuck three miles and a quarter south east of Dalmellington, 

 I observed in the greywacke a small bed of transition limestone 

 with much magnesia, four feet thick, dipping to the south-east at 

 an angle of 70°. 



In various parts of this district of transition country, called 

 Glenkens, I observed large beds of felspar porphyry, or what I 

 was at one time disposed to consider as transition greenstone. The 

 felspar is of various colours; but most commonly of a reddish cast, 

 something perhaps between brick red and Hesh red, but it is some- 

 times greyish white and greenish grey : it contains hornblende. 

 A few of these beds arc situated as follows. In the channel of the 

 burn of Halfmant opposite the church of Carsphairn, is a bed of 

 this rock traceable for 300 yards, and about HO feet thick, nearly 

 vertical, reddish at the south-westerly end, but on the end next 

 the north-east greenish grey. At Darnaw, lii miles from New- 

 galloway towards the N. W., is another bed of this rock 20 feet 

 tiiiek, containing very little horneblende, and of a greyish white 

 colour. It is exposed to view for 100 yards. The conunon people 

 took it, as well as the above mentioned bed at Ihilfmant, for 

 limestone ; and specimens of it, which I found had been procured 

 by blowing it with gunpowder, were actually sent to Lord Glenhee 

 at Barskimming under this idea, viz. of its being limestone. 

 Another bed of the porphyry occurs in the channel of the river 

 iJcugh, which falls into the Ken four miles below Carsphairn. It 



