on the different hinds of Coal. 329 



tion of it : it is mineral charcoal *, a pulverulent combustible, of 

 a fibrous structure, which the Germans name FaserTcohle, and 

 which has sometimes been named Anthracite, because it is com- 

 monly regarded as very difficult to burn. This substance is in- 

 terposed in the coal in beds which are perfectly distinct, often 

 very thin, and always parallel to the stratification of the beds. 

 By a great number of trials, M. Karsten has found that, in this 

 substance, the contents in charcoal are larger than in the coal 

 which comes from the same bed. He considers it certain that 

 the mineral charcoal has contributed to the formation of the coal, 

 and that a great part of the latter consists of that same vegetable 

 fibre from which resulted the mineral charcoal preserved in the 

 impressions of coal. Mineral charcoal, he adds, is one and the 

 same substance with coal. This is so true, that the pre-existence 

 of the fibres of plants, which, in the state of isolation, formed 

 the mineral charcoal, can only be recognized by the vegetable 

 impressions which have remained in the combustible. But, ac- 

 cording to the author, mineral charcoal is not, by any means, so 

 difficult of combustion as is commonly thought. Under the 

 muffle of an assay furnace, this substance burns with a sort of 

 flame which proves it to be very far from being in a state of 

 pure charcoal. The residue in charcoal which it yields on be- 

 ing distilled in the dry way, is incomparably more easy to burn 

 than the vesicular cokes of coal. 



In reality, in the operation of a high furnace, mineral char- 

 coal, when it occurs in large quantity, resists the action of the 

 most active blowing machines ; it reappears at the mouth of the 

 furnace, under the aspect of a fine charcoal powder, which is 

 named (Poussier) coal-dust, and it then seems to have under- 

 gone no alteration. But the same effect would take place were 

 powder of wood-charcoal applied in the same manner. It is the 

 pulverulent state in which it exists, that makes mineral-charcoal 

 act as if it were combustible, and which, in many circumstances, 

 renders its employment dangerous in a high furnace for melting 

 iron. Cokes themselves, when reduced to very small fragments, 

 heaped upon each other, produce a similar eflect, although less 

 complete. 



The same difference that is observed in the composition of 

 • Vide Jameson's Mineralogy. 



