COAL AND COAL-FORMATIONS. 



COAL, ITS ORIGIN AND FORMATION MINERALISED VEGETATION 

 RECENT PEAT-GROWTHS TERTIARY LIGNITES SECONDARY AND 

 PALAEOZOIC COALS PRIMARY ANTHRACITES AND GRAPHITES THE 

 COALS AS A MINERAL FAMILY CONVERSION OF VEGETABLE SUB- 

 STANCES INTO COAL ITS VARIOUS STAGES PEAT, LIGNITE, COAL, 

 ANTHRACITE, AND GRAPHITE CHARACTERISTICS OF THESE RE- 

 SPECTIVE STAGES IMPORTANCE OF COAL TO CIVILISED COUNTRIES 

 SPECIAL VALUE OF, TO GREAT BRITAIN. 



THERE is no mineral in the crust of the earth more essential 

 to modern civilisation than coal, and there is, perhaps, no 

 geological technicality more frequently made use of than 

 " Coal-formation," and yet how few have a rational or in- 

 telligent conception of either ! Every man and woman in 

 the British Islands is less or more acquainted with the ordi- 

 nary aspects of coal and its uses, and yet not one in a hun- 

 dred, perhaps, could give the commonly received explanation 

 of its nature and origin. Most people are aware that coal 

 is obtained by mining in rocks known as the Coal-forma- 

 tion, and yet how few know anything of the nature of 

 these rocks, how they were aggregated, or by what means 

 coal was formed along with them ! It is true that men of 

 science have their differences about these things, as they 

 have about many other matters ; but these differences are 

 for the most part trivial, and do not affect the general belief 

 either as to the nature of coal or the processes by which it 

 was aggregated. It is to state these beliefs in a simple and 

 intelligible way that we attempt the present Sketch, and 



