Prof. Harkness on the Sandstones and Breccias of Scotland. 395 



Maries, near Bethune. It is near this town that the depth to the 

 base of the Chalk is the greatest ; the sinkings which have been 

 conducted on the south gave a result at a smaller depth. 



Nearly 2,000,000 francs have been expended by various com- 

 panies, all formed of private persons ; and in more than 150 sinkings 

 numerous workings have resulted, which have increased beyond all 

 expression the wealth of these two departments, have developed a 

 portion of the coal-field of France, and enriched on a grand scale 

 the fortunate adventurers. The small basin of Fiennes and Harding- 

 hem, near Guisnes, is independent of this large one ; it is a coal- 

 deposit in the Mountain Limestone, and which has been worked for 

 some time past for local consumption ; the coal is found at a slight 

 depth, but the quantity of water renders the workings both difficult 

 and expensive. 



Similar works are being carried on in the department of the 

 Moselle, where they are tracing the prolongation of the Sarrebruck 

 basin beneath the New Red Sandstone. Eight companies have 

 already met with the coal between 200 and 300 metres in depth, 

 and are applying for concessions. It is in this quarter and in the 

 department Nord that the principal search is now being made. 



This letter was accompanied by an outline map of the district 

 referred to, on which were shown the extent of the several conces- 

 sions, the position and character of the most important of the 

 borings, and approximatively the length and breadth of the Valen- 

 ciennes coal-basin as indicated by the workings hitherto effected, 



3. " On the Sandstones and Breccias of the South of Scotland of 

 an age subsequent to the Carboniferous Formation." By Prof. 

 Harkness, F.G.S. 



The author first referred to a former paper, in which he had 

 described in detaQ some of these sandstones and breccias, especially 

 those of the neighbourhood of Dumfries. He then gave his reasons 

 for regarding the sandstones of Annan in the south-east of Dumfries- 

 shire to be continuous with, and of the same age as, those of Carlisle, 

 viz. of the Triassic age ; and pointed out several patches of sand- 

 stone and breccia in other parts of Dumfriesshire and in Ayrshire, 

 which lie either on the Carboniferous or the Lower Silurian rocks of 

 the district, and are probably referable to the Permian epoch. 



These sandstones and breccias appear to have been deposited sub- 

 sequently to the eruption of the trap- dykes that have dislocated the 

 coal-fields of central Scotland, and to have been always derived from 

 the neighbouring older rocks. The author divides them into four 

 distinct groups, viz. 1st (the lowest), breccias and sandstones, best 

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

 Ayrshire ; 2ndly, sandstones, for the most part false-bedded, well 

 seen in the Corncockle area, the Thornhill district, at Mauchline, 

 and in the vicinity of Dumfries ; 3rdly, hard thick breccias, best seen 

 at the Craigs, Dumfries ; and 4thly, thin-bedded sandstone, only 

 slightly developed, occurring at Castledikes, Dumfries, above the 

 breccia. 



Animal life abounded, in the form of Reptiles, during the period 

 2D2 



