IS

COAL MINES OF

is formed of trees, reeds, rushes, and othervegetable substances embodied together in thealluvial earth, having very distinct impressionsof trees, and being wholly of a ligneous andfibrous texture.

This coal is found within one foot from theSurface, and in the whole alternations of itsstrata does not exceed seventy-five feet indepth. It is curious that the Bovey coal be-comes less bituminized in its descent, as thelower seams approximate nearer to the slate-coal; it is called the compact carbonated coalby Kirwan, the common brown coal by others.

There is a manufactory on the Wear, a shortdistance from Sunderland, belonging to Messrs.Featherstone, for the purpose of decomposingthe coal and extracting from it the coal tar,petroleum, &c., and ammonia; it is similarto the one erected at Colebrook Dale by LordDundonald. A lamp-black is likewise obtainedhere in the same way as at the manufactory inthe county of Saarbruck on the Rhine.

It is from the second formation of Durhamand Northumberland that most of the coalis exported to London and other parts of thekingdom ; the independent coal being for themost part applied for home consumption, onaccount of its inferior quality.