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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Dec. 4, 



runs in a S.E. direction from the base of Little Queensberry to the 

 Ae Water. In the course of this brook the strata are well deve- 

 loped, and are inclined in the usual N.N.W. direction ; they consist 

 of anthracite, grey shale, black shale, and thin bands of soft white 

 shale, almost resembling clay. These beds are traversed with nume- 

 rous fissures and slickensides, so as to be in a great measure frag- 

 mentary. Graptolites occur in both the grey and the black shale, 

 but not in the white. They are, however, more abundant in the 

 black shale, and are commonly converted into iron pyrites. This 

 shale has a strong styptic taste, owing to the decomposition of the 

 iron pyrites and the production of sulphate of iron. Above these 

 deposits a series of thin-bedded, light drab-coloured shales prevail, 

 which are also fragmentary, and generally divided into rhomboidal 

 portions by fissures. These beds dip at an angle of 62° N.N.W., 

 and have dark-coloured graptolitic shale interstratified in their higher 

 portions ; no fossils, however, are to be seen in the drab-coloured 

 shales. 



After crossing the range of hills separating the Ae from the Bran, 

 the anthracite and shales are again met with in the course of a small 

 brook which joins the Bran at a spot called Wee-fall Cleugh. 



Second Band. — Returning again to near the point where the grap- 

 tolite beds were first described, we find, near B irk hill, eastwards 

 from Hartfell at Dobbs Linn, where Dumfriesshire and Selkirkshire 

 join, similar beds, extensively developed, and presenting all the cha- 

 racters that indicate the anthracite and black shales. On a line par- 

 allel to that before mentioned, and seven miles S.W. of Dobbs Linn, 

 we meet with a continuation of this bed in the course of the French- 

 land Burn, near Moffat ; here Graptolites are found in considerable 

 quantities in the dark-coloured shales. The brook runs along the 

 strike of these strata until it approaches the Frenchland Tower, 

 where the red sandstone makes its appearance, under which the an- 

 thracite beds extend in a W.S.W. direction. The inclination of these 

 beds is in the usual N.N.W. course at a high angle, and the hill, 

 rising immediately on the north side of this brook, and consisting 

 of greywacke sandstone, has its strata dipping in the same direction 

 at an angle of 70°. In a quarry on the Hunterheck farm, a short 

 distance to the south of Frenchland Burn, the beds are composed of 

 fine-grained greywacke sandstone with intercalated shales, dipping 

 N.N.W. at an angle of 73°. Annelid-like impressions, with vermi- 

 cular and other indefinite markings, occur on the faces of some of 

 the beds. 



After passing under the red sandstone the graptolite beds are 

 again seen at Garpool Linns, about a mile north from Beatock. 

 South of this the inclination becomes confused, and below the junc- 

 tion of the Garpool with the Evan, in the latter stream, the dip is 

 towards the E.S.E. at an angle of 73°; the rock consisting of red 

 and grey greywacke, shale, and greywacke sandstone. 



Between this locality and Moffat a trap dike of considerable mag- 

 nitude occurs, which is well exposed in the quarries of Coates Hill. 

 This may probably have been the cause of the local disturbance in 



