34 The Coal Mines of the United States of North America. 



THE COAL MINES OF THE UNITED STATES OF 

 NORTH AMERICA.* 



BY P. M. LUBBREN. 



In the United States coal is abundant, and can never be 

 exhausted. Between the western extremity of the Appa- 

 lachian coal-fields and Cincinnati, the different formations, 

 from the Devonian to the Lower Silurian, come up to the 

 surface in succession. At Portsmouth, next the lower coal 

 measures, comes the inferior, or conglomerate grit, or mill- 

 stone ; next it, the Waverly sandstone, the equivalent of the 

 Devonian. Then succeed the Upper Silurian slates and lime- 

 stones, and lastly, at Cincinnati, the lower Silurian groups 

 appear in the hills and beds of the Ohio. 



There is one vast coal-field extending from New York to 

 Alabama, which covers nearly one hundred thousand square 

 miles. Another coal-field in Indiana embraces about fifty-five 

 thousand square miles. Another in Michigan covers about twelve 

 thousand square miles. The grand total amounts to two hundred 

 and twenty-five thousand square miles, and the whole amount of 

 coal, estimating the average thickness of the beds to be fifty 

 feet, would be three millions and a half of cubic miles, a quantity 

 absolutely inconceivable. 



Before the late civil war, the average price of coal in 

 Pennsylvania was five dollars per ton, and in New York not 

 far from six dollars per ton.f The relative cost of trans- 

 portation to New York and to London from the mines was 

 then about the same. 



The principal portion of the coal used in the United States 

 for domestic purposes is brought from Pennsylvania. This 

 coal is anthracite, or hard, and the only large deposits of this 

 species of coal of a good quality in the United States, so far 

 as is known, are found in that region. Anthracite coal exists 

 in Rhode Island and Massachusetts, but it is much less com- 

 bustible than in Pennsylvania. 



The remainder of the vast coal-fields which we have enu- 

 merated comprise coal which is more or less bituminous, and is 

 more commonly used in this country for generating steam than 

 for domestic purposes. It is similar, however, to the English 



* State Survey of Pennsylvania. By Professor II. D. Rogers. 



Statistical Report on the Iron and Coal of Pennsylvania. Prepared by ."Dr. 

 Charles M. Wetherell, and published in a work entitled Science and Mechanism, 

 1853-4. 



State Survey of JVeio York. P»y Mr. Kail. ^Albany, 1843. 



State Survey of Virginia. By Professor W. B. Rorlgers. 



f Since the civil war the price of coal is more than double. 



