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[96] 



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beds, with no trace of a marine 

 auimal in them, are exceedingly 

 remarkable, and seem difficult of 

 explanation, without calling in the 

 aid of oscillations of the solid 

 surface of the earth, by which very 

 gradual risings and depressions are 

 effected. 



It is, however, the opinion of 

 some authors that the alternations 

 of freshwater shells with marine 

 remains, do not prove as many 

 relative changes of sea and land ; 

 but that the coal-measures were 

 deposited in an estuary, into which 

 flowed a considerable river, subject 

 to occasional freshes; and this 

 opinion is supported by the fact 

 of frequent alternations of coarse 

 sandstones and conglomerates with 

 beds of clay or shale, containing 

 the remains of the plants brought 

 down by the river. The quality 

 of coal, even in the same district, 

 very much depends on the nature 

 of the bed which immediately 

 covers the coal stratum ; for when 

 the superincumbent stratum is 

 sandstone, the coal is greatly dete- 

 riorated, being, more or less, mixed 

 with iron pyrites : on the other 

 hand, if the coal lie immediately 

 beneath argillaceous shale, its qua- 

 lity is much better. For economi- 

 cal purposes, coal may be deemed 

 more or less valuable, in proportion 

 to the quantity of bitumen it 

 contains. 



The study of the more ancient 

 coal deposits has yielded the most 

 extraordinary evidence of an ex- 

 tremely hot climate ; for it appears 

 from the fossils of that period that 

 the flora consisted almost exclu- 

 sively of large vascular cryptogamic 

 plants. M. Ad. Erongniart states 

 that there existed at that epoch 

 equiseta upwards of ten feet high, 

 and from five to six inches in 

 diameter; tree-ferns, or plants 

 allied to them, of from forty to 

 tity feet in height, and arborescent 



lycopodiacese, of from sixty to 

 seventy feet high, exceeding in 

 their development those now found 

 in the hottest parts of the globe. 

 The Newcastle coal-field is supply- 

 ing rich materials to the fossil 

 flora of Great Britain. The finest 

 example of distinctly preserved 

 vegetable remains is that witnessed 

 in the coal-mines of Bohemia. 

 " The most elaborate imitations," 

 says Prof. Buckland, "of living 

 foliage upon the painted ceilings of 

 Italian palaces, bear no comparison 

 with the beauteous profusion of 

 extinct vegetable forms, with 

 which the galleries of these in- 

 structive coal-mines are overhung. 

 The roof is covered as with a 

 canopy of gorgeous tapestry, en- 

 riched with festoons of most grace- 

 ful foliage, flung in wild, irregular 

 profusion over every portion of its 

 surface. The spectator feels him- 

 self transported, as if by enchant- 

 ment, into the forests of another 

 world ; he beholds trees, of forms 

 and characters now unknown upon 

 the surface of the earth, presented 

 to his senses almost in the beauty 

 and vigour of their primeval life ; 

 their scaly stems, and bending 

 branches, with their delicate appa- 

 ratus of foliage, are all spread 

 forth before him ; little impaired 

 by the lapse of countless ages, and 

 bearing faithful records of extinct 

 systems of vegetation, which 

 began and terminated in times of 

 which these relics are the infallible 

 historians." I can hardly conclude 

 this article better, than by again 

 drawing on the composition of the 

 above quoted elegant and eloquent 

 author, in transferring to my page 

 from his delightful work on Geolo- 

 gy and Mineralogy the following 

 beautiful passage. " The impor- 

 tant uses of coal and iron in 

 administering to the supply of our 

 daily wants, give to every indi- 

 vidual amongst us, in almost every 



