24 Strata of Different Ages. 



than those in the bed of limestone, No. 1 ; the organic 

 forms, plants or animals as the case may be, in the 

 conglomerate, No. 3, were buried among the pebbles at 

 a later date than the shells in the shale, and the re- 

 mains of life in the sandstone, No. 4, were latest of 

 all ; and in each bed, each particular form found there, 

 lived and died before the sediment began to be 

 deposited that forms the bed above. All these beds, 

 therefore, contain relics of ancient life of different 

 dates, each bed being younger or older than the others, 

 according as we read the record from above or from 

 below. It is evident that the same kind of reasoning 

 is equally applicable to the inclined strata of fig. 2, or 

 to the contorted beds of fig. 3. 



But if we leave a petty quarry or sea cliff, and ex- 

 amine strata on a larger scale, what do we find ? On 

 many a coast, where the cliffs consist of stratified rocks, 

 a lesson may easily lie learnt on the method of under- 

 standing the order, or comparative dates of deposition 

 of geological formations. The Liassic, Oolitic, and 

 Cretaceous cliffs of Yorkshire, from the Tees to Flam- 

 borough Head, form excellent examples ; or the coast 

 of Devonshire and Dorsetshire, from Torquay to Port- 

 land Bill. I take part of the latter as an example, 

 from Lyme Regis to the eastern end of the Chesil 

 Bank. 



If we eliminate those accidents called faults, we 

 there find a succession of formations arranged some- 

 what in the manner shown in diagram No. 5. 



The horizontal line at the base represents the shore 

 line. On the west (1) represents red marly strata, 

 known as the New red or Keuper marls. These pass 

 under thin beds of white fossiliferous limestone (2), 

 known as the Rhsetic beds. These in their turn pass 



