Polytechnic Association. 943 



tion has long been called to the existence of these lignites, but very 

 little has been said in regard to any accurate estimate of their value 

 as fuel. A large proportion of the territory where they are found is 

 destitute, to a large degree, of wood. There is much less forest there 

 than in most other parts of the United States. The question, what 

 they shall use there for fuel, is one of special importance. They 

 require fuel, not only for ordinary uses, but for metallurgical purposes. 



Our country, as a whole, is better supplied with mineral fuel than 

 any other in the world. "We have in the Mississippi Yalley several 

 great coal basins, comprising an aggregate area of 150,000 square 

 miles. Great Britain is better supplied with coal than any other 

 country in Europe ; and it owes its great wealth ail( i power mainly to 

 its store of fossil fuel. But it is calculated that within 300 years, in 

 all probability, its store of coal will be entirely exhausted ; and then 

 Great Britain must lose the position she occupies and sink to the 

 position of a second, a third, or even a fourth rate power. 



The great coal basins of our own country, which belong to the car- 

 boniferous age, are altogether found in the Mississippi valley and on 

 the Atlantic coast. Here you will see upon the map the Allegany 

 3oal field, which reaches 750 miles, from the southern boundary of the 

 State of New York to Alabama, comprising an area of 60,000 square 

 miles. The out-liers of this coal field, separated from it by natural 

 convulsions, are a line of detached basins, containing, in many cases, 

 a semi-bituminous coal. In Rhode Island, and partly in Massachu- 

 setts, there is a small coal basin where the anthracite has been partially 

 converted into the condition of graphite. There are coal basins still 

 further north, beyond our limits, in Nova Scotia. There is a small 

 coal basin in Michigan, and there is a coal field in Illinois, and another on 

 the west of the Mississippi, reaching, with irregular outline, from Iowa 

 into Texas, the western border of which is concealed by the overlying 

 rocks. 



West of this we have no more carboniferous coal. All the area 

 west of Omaha is without carboniferous coal, and yet there are deposits 

 there of a carbonaceous material that rivals in thickness any of the 

 coal beds. They are all much more modern, being either cretacious or 

 tertiary, within our lines ; while south of our lines there are some 

 which are triassic. These are the beds of lignites, or imperfectly 

 formed coal. 



I have here a table and specimens of the various kinds, showing the 

 progress of the transformation of wood into coal. The first change 

 is its transformation into lignite, which is another name for fossil 



