Chemical Examination of Bituminous Coal. 373 



Rumford caused balls to be made of clay and fine coal moistened 

 and kneaded together, the object bemg not only to economize 

 the waste coal, but also to accumulate and radiate the heat. 



As in the Mid Lothian coal there is very little iron, it is not 

 likely that the ashes will readily form slag or clinker to obstruct 

 the bars of a grate, or to accumulate like a fungus, upon the walls 

 of a furnace. 



Should there be occasion to convert the Mid Lothian coal into 

 coke, it would afford that very important fuel of an excellent 

 quality. If the process were conducted at a low heat, it is proba- 

 ble that a very brightly burning gas would be obtained, fitted 

 for illumination, especially if it were mixed with a requisite pro- 

 portion of the gas from rosin, as is done in the gas works in Bos- 

 ton, where Pictou coal of Nova Scotia is employed for this pur- 

 pose. The Mid Lothian coal contains so little sulphur, that for 

 every practical purpose it may be regarded as free from that com- 

 bustible which is so injurious to the working of bar iron and steel 

 by the forge and hammer, especially in the very important opera- 

 tion of welding. From repeated trials made with the Mid Lo- 

 thian coal by our smiths in this city, it appears perfectly well 

 adapted to their uses, especially where a hollow fire is desired, 

 and when a powerful heat is necessary for large work with a 

 strong blast. One of our best smiths, having made a comparative 

 trial of the two, remarks, that it does not ignite as soon as the 

 Newcastle coal, but gives a surer good welding heat, and lasts 

 nearly one quarter longer. 



This coal is an excellent fuel for a parlor grate. No bitumen 

 exudes during its combustion ; on breaking a heated mass by 

 the poker, there is no liquid tar covering the separated frag- 

 ments, but a bright flame instantly kindles on the newly exposed 

 surfaces, which radiates heat powerfully and illuminates the room 

 with a cheerful radiance. 



There being no liquid bitumen, the combustion of this coal is 

 attended with less smoke than is usual with bituminous coals; 

 with a well drawing vent, there is scarcely a perceptible odor and 

 no deposit of coal dust in the room and upon the furniture. 



From a considerable experience in using it by us in a family 

 parlor, it proves to be a very desirable fuel. We presume that it 

 would prove an excellent fuel for locomotives and for steam en- 

 gines, as it is abundant in flame so important to the production of 



