MODE IV. LIGNITE. 



we cannot be positive that these local indica- 

 tions have really any relation to earthy lignite. 



" It may have been observed, from what has 

 been just said on the situations peculiar to some 

 varieties of lignites, that this fossil combustible 

 belongs to soils of the most recent formation, 

 since it is only found in accretions of sand or 

 argil. It is almost never met with under rocky 

 beds, except in coarse carbonated lime, and un- 

 der basalt. In the mountain of Ringe Kuhle in 

 Hessia, several thick layers of lignite are ob- 

 served, lying on a sandstone, and separated by 

 layers of potter's clay and sand (Mohs). On 

 the sea shore, near Calais, fragments of lignite 

 have been picked up, which were penetrated 

 with crystals of quartz, very limpid, and disposed 

 in spheres. 



" Lignite then is of a very different formation 

 from that of coal ; and M. Voigt thinks that 

 there is no transition between those two com- 

 bustibles. 



" The air which circulates where lignite is 

 wrought is generally bad*." 



In his Essay on Geology, Faujas has given an of Cologne, 

 accurate and ingenious account of the prodi- 

 gious mass of lignite near Cologne,which extends 



* Brongn. ii. 30. 

 VOL. I, 2 Q 



