mans. With regard to their depth, a more accurate idea may be 

 formed from the annexed sketch ; remarking, in this place, the 

 lower the coal, the less the depth of the incumbent strata. The 

 depths of the coal strata are various, as will be seen in the following 

 table, which shows the depth of the several coal beds which are 

 worked. 



The lower coal strata furnish the best and strongest substance 

 for burning. The shaft, from the grass to the bottom of the last 

 coal stratum, is seventy-five feet deep. It has been bored thirty- 

 three feet still deeper, but nothing was discovered but a kind of 

 muddy clay, intermixed with sand. The disposition of the strata is 

 displayed by their method of working : they begin on the top, and 

 clear away to the distance of eight or ten fathoms, and work down, 

 in a perpendicular direction, through the various strata, to the bot- 

 tom of the shaft ; then recommence their operations, &c. 



The direction of the strata is from north to south ; the inclina- 

 tion or dip tending to the latter. This inclination is computed to 

 be about one foot in six ; the leading part is from east to west. The 

 northern part reaches to the surface, within an hundred yards of the 

 shaft, where it is cut off by a bed of sand ; to what depth the southern 

 extremity reaches has not been, and possibly cannot be, ascertain- 

 ed ; it has been found, however, to extend a quarter of a mile. The 



