GEOLOGY. 305 



ashes. It possesses a much larger proportion of carbon than ordinary 

 bituminous coal. 



The total annual produce of the China coal mines is estimated by 

 Dr. Macgowan at 820,000 tons, valued at about six millions of dollars. 

 The paucity of the supply is owing, not to the poverty of the mines, but 

 chiefly to the want of those facilities for mining which the steam- 

 engine can alone supply. Mines, often, when they become most pro- 

 ductive, are suddenly filled with water and rendered useless. 



To appreciate rightly the value of the vast coal deposits extending 

 from Corea to Siam, regard must be had to the increasing commerce 

 of the Pacific, to the revolution which seems on the eve of taking place 

 in the route of communication with western nations, and the prospective 

 greatness of the Anglo-Saxon states springing into existence on its 

 eastern shores. Of their capacity, aided with the appliances of foreign 

 skill and capital, to supply all demands which the steam-engine may 

 make upon them, both for manufactures and navigation, there can 

 exist no doubt. Nor have these primeval forests been stored upon 

 the continent alone ; they abound in more accessible situations, isolated, 

 as it were, expressly for steam navigation, in the islands of Japan, 

 Formosa, and Borneo. Before the application of steam and coal to 

 navigation, a sceptical philosophy might have questioned the utility 

 of deposits of this mineral in the torrid zone, and immediately under 

 the equator ; but the design of the Omniscient Artificer of this beautiful 

 sphere is now obvious, affording another evidence that He left nothing 

 to fortuitous circumstances, and another lesson fraught with instruc- 

 tion for reflecting minds. 



DDIEXSE COAL BED. 



MR. J. DILL, of Ohio, in a recent communication to an Ohio journal, 

 says : " Reports of an immense structure of coal, in the vicinity of 

 this place, have long been circulated in Central Ohio. I first heard of 

 it in the winter of 1848-9 ; it was then reported to be about ninety 

 feet thick. Further examinations ascertained the thickness of the 

 uncovered part, in the face of a deep ravine, at 112 feet. A few days 

 since a gentleman of high standing informed me, that an acquaintance 

 of his, with some others, had stripped the upper surface of the bed 

 and bored through the coal stratum to ascertain its thickness, and 

 found it to be 138 feet." 



Mr. J. W. Foster, U. S. Geologist, in a letter to the editors of Silli- 

 man's Journal, in reference to the above communication, says : 

 " Although this extent is at variance with all other previous knowl- 

 edge of carboniferous deposits, yet I have no doubt that, in the main, 

 it is true. I conversed with several intelligent persons who had seen 

 the deposit, and all concurred in representing it as one of unparalleled 

 thickness. It is exposed for several miles in the banks and along the 

 bed of a small stream one of the tributaries of the Hocking river. 

 Like most of the coals of Ohio, it is highly bituminous, and is more or 

 less impregnated with iron pyrites, which, for manufacturing purposes, 

 impairs its value. The deposit, instead of being one bed, may be 



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