296 COAL. 



tain limestone, and which has been, with an improper 

 exclusion, termed the Independent coal. But as no 

 opportunity has yet offered, for considering that which 

 occurs among the primary strata, I must here give it 

 a place ; that, in this and the following chapters, the 

 whole question relating to this mineral may he seen 

 in one continuous view. 



The connexions of primary coal present very little 

 interest or instruction, beyond the mere existence of 

 this substance among primary rocks. It has occurred 

 in gneiss, in micaceous schist, in primary limestone, 

 and in a conglomerate rock said to belong to the pri- 

 mary class. Thus it has been discovered in various 

 parts of the continent of Europe, as in France, Nor- 

 way, and Germany; but as yet no example has been 

 observed in the British dominions. In all these cases 

 it forms very limited masses ; being, in some instances, 

 in detached lumps ; in others, in forms said to resem- 

 ble those of veins rather than strata. J need not say 

 that a thin and non-persistent stratum is easily called 

 a vein. 



The origin of this coal remains a matter of dispute 

 among geologists. When the mineral carbonaceous 

 substances occur among the secondary strata, they 

 commonly carry their proofs of a vegetable origin 

 with them, as will be shown hereafter. If it may not 

 be so easy to admit this in the case of primary coal, 

 it does not imply any impossibility. I have shown, 

 in former chapters, that organic animal remains do 

 exist among the primary strata; and as I need not 

 repeat the reasonings then given, this hint will suffice 

 for the possible explanation of the origin of primary 

 coal. That it should occur in limestone and in a con- 

 glomerate, are analogies to its position in the secon- 

 dary rocks, of which the value is here obvious. 



