76 Trnnnactioibs. 



varying in some parts to a purplish tiut. It is very hard 

 and durable, and makes an excellent building material, being 

 much used in the locality. Thei'e are associated with the Grau- 

 wackes a thin flaggy grit, and black Graptolitic shales, so often 

 found in the scores and burns, which are formed in the hill sides 

 by denudation. Fragments of these black shales may be found 

 among the gravel in the bed of the Annan, six or seven miles 

 distant from the parent rock at Hartfell, and I have frequently 

 picked up some very good specimens brought down in this way. 

 There is also a red sandstone rock, said to be of tlie Permian Age, 

 which is found largely at the base of the hills, and in some parts 

 has been denuded and carried a considerable distance into the 

 valleys, where it is in many places mixed with small pieces of the 

 Silurian grit, giving an idea that the hills had been covered with 

 this red sandstone at an early epoch, before it was washed down 

 to the base of the hills and tliere preserved. One of the best 

 exposures of it is to be found in sections along the burn from 

 Haitfell, a short distance off the main road going \i\) to the 

 well, and in other parts such as at Beldcraig, Wellburn, and 

 Frenchland burn. I have no doubt it is the equivalent of the 

 Corncockle moor stone, but by no means equal to it, as it does 

 not seem to be fit for any economic purpose whatever. 



There are few trap dykes or outbursts of igneous rocks 

 observable in the locality, except at Coatshill Quany, which is 

 wrought for road metal, cfec. There is also another exposure of 

 the same dyke now in the railway cutting between Moffat and 

 Beattock, which was visited by this Society last summer (August 

 4th, 1884). We may safely state that tliei-e are none of the 

 other rock formations which appear to have received such a 

 crushing and contorting as these old Silurian rocks ; and it is 

 remarkable that there are so few faults to be found in the 

 district of any magnitude. 



We find the black Graptolitic shales in bands, tilted up at 

 different angles from their original bed, in many parts inverted, 

 while veiy frequently they are of a folding character, existing in 

 bands of various heights, from three to five or six feet in thick- 

 ness, with a parting of a white kind of pipe clay, of from two 

 inches to six inches in thickness, which gets exceedingly hard 

 when in a dry situation. Tlie black Graptolitic shales seem to 

 be composed of a dark mud, slowly and quietly laid down in a 

 deep sea bottom, swarming with Graptolites and Crustacea, with 



