No. 7. DEPARTMENT OF AGRICULTURE. 4<;9 



the percentages of constituents and especially so in the amount of 

 volatile matter and sulphur contained. Connellsville coal (Pittsburg 

 bed) valuable as it is as a coking coal can not compete with the 

 Youghiogheny-Westmoreland coal for gas purposes, nor could the 

 latter compete with the former for the manufacture of coke. A good 

 grade of gas coal has been mined at Keynoldsville in Jefferson county, 

 and a good coke is made in the vicinity of Punxsutawney, in the 

 same county. 



Cokes are manufactured from the coals of the Upper Freeport and 

 Upper Kittanning beds along the main line of the Pennsylvania rail- 

 road, between Cresson and Johnstown, as well as a small amount in 

 Huntingdon and Bedford counties. The main source of supply of 

 coke in Pennsylvania is drawn from the Connellsville region, in fact, 

 it may be said that none of this coal is shipped in a raw state but 

 the entire output is manufactured into coke. The Youghiogheny- 

 Westmoreland coal output is largely devoted to the manufacture of 

 gas. This is as it should be, because these coals possess to a very 

 high degree the essential properties requisite for the manufacture of 

 coke and gas. 



Coals from certain districts in Pennsylvania have long enjoyed and 

 retain enviable reputations for excellence for specific uses. In fact, 

 so strongly have they become intrenched, that they are now ac- 

 cepted as standards, and when coals from other districts are brought 

 into the markets, these coals are used for comparison. In these 

 days of brisk competition, no district can long maintain its lead, 

 unless its coals possess the essentials requisite. 



The question arises: What are the essential characteristics to be 

 sought when purchasing coal for specific purposes. 



The specific purposes, it is assumed are: 



(1) Steam generation. 



(2) Gas manufacture. 



(3) Coke manufacture. 



(4) Smithing purposes. 



(5) Domestic uses. 



Steam Coal 

 For the generation of steam, a coal should possess 



(1) A high evaporative power. 



(2) It should kindle readily. 



(3) It should burn steadily and generate a large body of steam 

 quickly. 



(4) It should not clinker, even when subjected to a high heat. 



(5) It should be low in ash. 



(6) Its percentage of sulphur should not exceed in any case, one 

 per cent., as this is detrimental to both grates and flues. 



(7) The contained volatile matter should not exceed the amount 

 requisite for rapid combustion. 



(8) It should bear transportation well, so that it will not be 

 seriously reduced to fine coal. 



