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sequent Devonian period it is not easy to say ; but that they were again under 

 water during the carbouiferous period there ia evidence to prove in the coal- 

 field about Leebotwood. 



The last submergence of the Longmynd would seem to have been during 

 the glacial period. Thero are no facial marks here such as are met with in the 

 Pass of Llanberis, Snowdon, Cader Idris, and other mountains in North Wales, 

 from which it mi^ht be inferred that they were at this period submerged. And a 

 strong confirmation of this is found in the planing off, so to speak, of all the 

 higher portions of this chain of hills. This table land was at that time per- 

 petually drifted over by huge icebergs, which, by their enormous weight, carried 

 away all the higher portions. A similar action is going on this day over the 

 banks of Newfoundland and the adjacent ocean bed. From the high mountain 

 chains of Greenland, and from the Polar sea, great masses of ice, constantly 

 detaching themselves and drifting southwards with the ocean currents, sweep 

 across the banks, and so reduce them to a uniform level. It is quite consistent 

 with this hypothesis that we find in some parts of this neighbourhood (at least 

 I know of one place near Buildwas where such occurs) a quantity of travelled 

 blocks, some of them of granite. They are the load which these glaciers 

 once carried, and which sank to the bottom as they melted. 



Subsequently to this period the Longmynd was with all this part of 

 England elevated from the sea, and in the course of this its last upheaval was 

 formed that vast estuary of the Severn, which extended from the Dee to the 

 Bristol Channel. To this period must also be assigned those great mounds of 

 gravel and sand which fill up many parts of the Stretton valley. 



As for the organic life of the time when these hills were in process of 

 formation, we have but the most meagre traces. "Whether this is the result of 

 peculiar circumstances, such as their geographical position, the climate of this 

 part of the world at the time, or whether, as Sir R. Murchison supposes, the 

 area of the Longmynds was really the infancy of the whole world of organisms, 

 are not easy questions to answer with confidence. A few worm tracks are nearly 

 all the unequivoocal evidence we possess that any living creatures existed on 

 these ancient tracts of mud and sand. Portions of trilobites are also said to 

 have been discovered, but as far as my information goes they are very obscure. 

 It may be noticed, however, that these traces, such as they are, prove posi- 

 tively the existence at that time of a flat sea beach, alternately above water 

 and alternately submerged, since it is only under such circumstances that their 

 preservation is possible. Pain marks and cracks in the mud caused by the heat 

 of the sun's rays may also be found, also many good specimens of ripple marks. 

 In rocks of the same age in Ireland a curious fossil, probably a kind of coraline, 

 called Oldhamia antiqua, is found, but no trace of it has been discovered here. 

 Negative evidence is always unsatisfactory. That particular fossils are not 

 found in a certain stratum is no proof that they did not exist elsewhere at the 

 time when it was formed. There are some organisms, such as e.g., the Lingula 



