4 86 



ON THE COAL-FORMATION 



ver, excepting in the quarries which have been 

 opened, and pits which have been sunk: from 

 these, however, we have this general remark to 

 make : That the corners of the strata, under the 

 carse soil, are very much rounded, and apparent- 

 ly water- worn. Under the till or coarse clay, the 

 corners are much more acute, and the strata are 

 cut off, or meet the clay-cover with abrupt faces 

 or steps, which are always formed by a natural 

 crack or fissure, termed by miners a back or cutter, 

 nearly at right angles to the line of dip. 



The coal-formation, or main coal-field of the 

 county, is divided into three distinct fields, form- 

 ed by two great slips, termed the Great South Slip 

 and Great North Slip ; and the fields are named 

 the North Field, the Mid Field, and South Field, 

 upon all of which great and extensive collieries 

 have been erected. 



In the following general description, we must 

 begin about the middle of the North Field, and 

 proceed southward to the Forth ; because that 

 part of the North Field betwixt the Devon works 

 and the Ochill mountains, not having been explo- 

 red with sufficient accuracy, we can only offer 

 some ideas regarding it, assumed upon rational 

 principles. 



The strata having been ascertained as far north 

 as that part of the country where the Devon Iron- 

 works are built, we begin at that point. Towards 

 the crop of the strata, the dip is at an angle of 



