TRANSACTIONS OF THE SECTIONS. 641' 



Mr. Bald, in giving a section of the edge seams, estimates the 

 total depth of the coal strata in the basin to be at least 500 fa- 

 thoms, and that the aggregate amount of the thickness of the 

 whole of the seams of coal, twenty-six in number, is 109 feet 

 6 inches. 



Although the Firth of Forth is generally considered to be the 

 northern termination of the Edinburgh coal-fields, there appear 

 to be sufficient reasons to warrant the supposition that the coal- 

 district on the opposite coast of Fifeshire was originally a part 

 of the same deposit. That the coal strata do extend across the 

 water is evidently shown both by the circumstance of their be- 

 ing worked near Wemyss Castle, 300 yards beneath the bed of 

 the river, and their outcrop being seen on both sides of the 

 Forth beyond the low-water mark, as well as at Inchkeith, 

 which is situated in the middle of the channel ; at the same time 

 it must be confessed, that with the knowledge we possess re- 

 specting them it would be very difficult to prove their exact 

 correspondence, either by their lines of bearing or by the qua- 

 lity of the coals : but when all the disturbances by which they 

 are known to have been affected on both sides of the Forth are 

 taken into consideration, it will not appear improbable that the 

 same causes may have operated, even in a still greater degree, 

 to pi'oduce similar derangements and dislocations in those parts 

 that are now concealed beneath the water, which might suffi- 

 ciently account for any alteration that may be observed in their 

 appearance when they emerge from it on either shore. 



The upburst of the trap hills that surround Edinburgh, 

 which, from the occurrence of glance coal, and other appearances 

 observable in them, we may with great probability suppose to 

 have taken place after the deposition and consolidation of the 

 coal series, may very possibly have obliterated many beds of 

 coal that might have previously existed where they now 

 stand, and have variously affected all the others within reach of 

 their influence. 



On the other side of the water we see, by the plan accom- 

 panying Mr. Landale's reports on that district, that the coal 

 strata meet with so much intei*ruption froiii trap dykes, that 

 instead of proceeding to any distance on their regular lines of 

 bearing, the greater part of them have been deflected to the 

 eastward, and take directions nearly parallel to the line of the 

 coast. 



It appears also from the same authority that the number of 

 coal beds, and the total thickness of the coal in them, in the 

 Fife district, is very nearly the same as in the Edinburgh coal 

 district, according to the accounts given of it bv Mr. Eald, viz. ; 



183i<. 2 T 



