1 80 The Dukinfield Coal-pits. 



are interesting- to naturalists, being storehouses, more 

 or less rich, of some of the most beautiful fossils known 

 to science. In the shaly substance that forms the roof 

 of the coal-seams, are innumerable specimens of those 

 handsome scarred and fluted slabs that represent the 

 plants of the era when the coal-deposits were formed, 

 and especially of those which, having their leaf-scars 

 disposed like diaper-work, have been named Sigilla'rias, 

 or " Seal-impressed plants." There are many different 

 species found in a mine, and many different varieties 

 of diaper, nearly every species partaking of this 

 elegant character ; so that in the ancient times when 

 the plants were alive, and formed jungle-like for- 

 ests, whatever the supposed dreariness caused by their 

 want of showy flowers, it must have been compensated 

 by the ornamentation of the stems, which seem to have 

 been to the stems of all other plants, recent as well as 

 fossil, what Norman porches architecturally are to plain 

 ones. The thinnest veins of coal are in general the 

 best preservers of the remains in question ; and those 

 veins are the richest, and contain the most perfect speci- 

 mens, which have the quick slope called a "dip" a 

 circumstance accounted for by supposing that, owing to 

 the dip, the water drained away at the period when the 

 vegetable matter had newly accumulated. 



To survey one of these grand and strange museums of 

 Nature's antiques is in a measure comparable with a 

 visit to Herculaneum or Pompeii A past world lies 



