116 Mr Bald on the Coal-field 



the coal strata in the vicinity of Dalkeith, viz. that the edge- 

 coals, and accompanying strata, found at the collieries of Drum 

 and 'Gilmerton, four miles south of Edinburgh, with the well- 

 known bed of limestone, which lies immediately under all the 

 workable coals, decline into the centre of the valley, southward, 

 to a very great depth, and then deflect, rising to the south, and 

 are again found at Dalkeith, where the lime rock, under the 

 lowest workable coal, is found, and wrought extensively. We 

 therefore conclude, that the bed of lime-rock in the lower part 

 of the Dalkeith section, is a continuation of the lime-rock at Gil- 

 merton ; that the coal named the Parrot Coal in the sections, 

 corresponds with the lowest coal at Gilmerton, next the lime- 

 rock, named the North Green Coal ; and that the several coals 

 above the parrot-coal in the section correspond with the edge- 

 coals which lie above the said north green coal. 



The following minute section of the strata was made in the 

 course of running a day-level some years ago from the South 

 Esk, to drain the Marquis of Lothian's coal-field along the Ro^ 

 man-camp Hill. The strata cut through had a dip of from one 

 in four to one in three ; but the section now exhibited shews the 

 strata in a perpendicular line at the South Esk, calculated from 

 the horizontal section ; which perpendicular section extends to 

 the depth of 387 fathoms to the lime-rock. In it are found no 

 less than 27 beds of coal, making a total thickness of 82 feet 8 

 inches. The different beds of separate and distinct coals passed 

 thrpugh are of various thickness, extending from 6 inches to 9 

 feet, and lie at very various distances from each other, as is com- 

 mon in all coal-fields. 



Section of the Coals, and their accompanying Strata, beginning 

 at the surface. 



Fath. Ft. In. Fath. Ft. In. 



1. Alluvial soil - - 2 Brought forward 10 4 6 



Slate sandstone - 2 10. Coal - - - 6 



White sandstone - 4 Indurated clay - 14 



Red sandstone - 2 4 Do. do. hard - 10 



5. Blue sandstone - 10 ^q^| . . _ 16 



White sandstone - 4 indurated clay . 16 



Red sandstone - 5 15. White sandstone - 16 



Slate sandstone - 3 Red sandstone - 5 3 



Slate clay - - 2 6 slate clay -.040 



Garry forward 10 4 6 Carry forward 20 2 6 



