58 Mr Menteath 07i the Geology of Nithsdale. 



Basin of Dumfries. — The Basin of Dumfries, the last of 

 those that form Nithsdale, is separated from that of Closeburn, 

 by a considerable ridge of grey wacke, nearly five miles in breadth. 

 Through this ridge the Nith finds itself a passage, and enters 

 the Basin of Dumfries. This Basin is open on the south, and 

 is there bounded by the Solway Frith ; but on the east, north, 

 and west, is encircled by the grey waeke, except at the south-east, 

 near Mousewald Kirk, where it unites itself to Annandak. 



The greywacke hills, which partly surround the Basin of 

 Dumfries on the east, north, and west, are of lower elevation than 

 those of Closeburn, and of much less pleasing forms. They are 

 green, and cultivated to their summits; but produce fewer 

 streams than the three preceding Basins. Of these, the only one 

 of any note falling into the Nith below Lincluden Abbey is the 

 Cluden. In its long, pleasing, and winding course, it passes 

 through the parish of Glencairn, a pretty wooded sequestered 

 basin. The whole of it, as well as its encircling mountains, are 

 greywacke, separating it from those of New Cumnock, Sanquhar, 

 and Closeburn. The Lochar, a detached and independent 

 stream, in its way to join the Solway at Carlaverock, passes 

 through an extensive peat-moss,* which, by its broken, black, 

 swampy appearance, casts a gloom on all the beautiful scenery 

 of the lower part of the Basin of Dumfries. 



The interior of the basin of Dumfries is filled entirely with 

 the New red sandstone, for as yet no traces of the white or grey 

 have been observed. This red sandstone is much softer, and 

 decays more rapidly by exposure to the weather than that of 

 Closeburn. At I^ochar Bridge, and at Castle Dyke quarries, 

 where this red sandstone is raised, proofs may be seen of its de- 

 composing nature "I-, On the west side of the Nith in Gallow- 

 way, to the south of GrifFel, which is sienite, near Arbigland, the 

 coal formation appears ; but the strata are so much on their 

 edge, and so insignificant in their thickness, that they are of no 

 value. It is very probable that the Solway Firth is a great coal 

 basin, for coal is worked on the English side, as between Work- 



• In it often are found the bones and horns of a large species of deer, 



t At the latter place, the mineralogist will find imbedded in the red sandr 

 stone, curious specimens of basalt, and other rocks of that kind, some of them 

 exceeding the ?ize of a man's head. 



