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that it seemed as if you had discovered another world, just beneath 

 the crust of that which you had lately quitted. There can undoubt- 

 edly be hardly any scene, which can be presented to the view, 

 capable of exciting more astonishment than the one you describe. 



Wonderful indeed must have been the scene^ after a dark and 

 dreary descent through so many fathoms of dripping strata, which 

 must have offered itself, when you made your entrance into a cavern 

 from which the glimpse of day was excluded ; where the roof, the 

 floor, and the walls, presented every where to the eye the same 

 jetty black ; except where the oozing drop, or the brilliant spar or 

 marcasite, reflected the flames of the lamps; which, disposed in 

 various parts, lighted the inhabitants of these seeming Vulcanian 

 regions to their labours. These, as you inform me, were separating, 

 with their ponderous instruments, into fragments of a convenient 

 size, parts of the immense mass of coal, which years and years of 

 labour had seemed to have left inexhaustible. Such an assemblage 

 of striking and entirely novel appearances could not fail of exciting 

 a train of thoughts widely different from any your mind had yet 

 known, and must necessarily have rendered you anxious to gain 

 some information as to the history of these regions, This part, as 

 well as the rest, of my engagement, I shall perform with the utmost 

 readiness, pleased with the idea that I may thus render your de- 

 lightful tour more interesting and instructive. 



Common coal, that substance so eminent for its utility to man as 

 an article of fuel, is the fossil which therefore shall next claim OUT 

 attention. 



COAL is a black, solid, and compact substance, generally of a 

 foliated or rather laminated structure, which necessarily directs its 

 fracture. Its specific gravity is 1.25 to 1.37. It possesses a mode- 

 rate degree of hardness, but is more brittle than Cannel coal; than 

 which it also takes fire less readily, and is longer in consuming. It 

 cakes into cinders mare or less during its combustion* according to 



