212 



A BURIED VALLEY. 



the fossils, of a true Shale and of a natural deposit in some unknown 

 depth of a Carboniferous ocean. With regard to real shore deposits, 

 I suppose similar causes affected the preservation of fossils in the 

 past ages of the world's history, as affect the preservative conditions 

 of forms belonging to living species. On the coasts of South Africa, 

 and also of Bermuda, there are shell sands in fine condition consisting 

 of minute shells, Entomostraca and Polyzoan forms mingled with 

 calcareous weeds, and debris of Corals. It is easy to pick out from 

 this shell sand forms of Polyzoa in a beautiful state of preservation, 

 but a survey of only a small portion of the sand is sufficient to satisfy 

 the student under what conditions the mass was formed. Even the 

 best preserved are water-worn or slightly eroded. Material brought 

 from even a moderate depth of the ocean, from twenty to forty 

 fathoms, fragments are sharp in outline and tolerably well preserved. 

 Applying the same rule to the past life of the earth — ocean fossils 

 and shore debris tell their own tale, whether from the^ Carboniferous, 

 Devonian, or Silurian Limestones or Shales. If therefore the student 

 of Palaeontology would, in his investigations, rigidly apply this rule 

 in all his labours, many interesting details respecting the preservation 

 and distribution of species and groups w^ould be brought to light, 

 and additional interest would surround the study of the dead species 

 and dead groups of the inevitable past of our globe's historical life, as 

 surrounds the study of species belonging to living nature. 



( To be cojiiinued. ) 



A BURIED VALLEY. 



The steady pro£^ress of the Mersey Tunnel has been watched with keen 

 interest, and its approaching completion is a matter for general satisfaction. 

 Geologists especially have been waiting for the evidence which the tunnel 

 works would most probably afford on the question of the pre-glacial river valley, 

 which Mr. T. Mellard Reade, F.G.S.. so long ago as 1872. predicted would be 

 found to exist below the level of the present valley of the Mersey. Mr. Reade's 

 deductions were based upon certain borings at Widnes and in the upper reaches of 

 the Mersey, revealing an unexpected gorge, deep below the drift on which the 

 town of Widnes stands, and connecting the rocky bed above Runcorn Gap with 

 that below it by a steep gradient. The course of the pre-glacial river was pre- 

 sumed to be in the main identical with that of the existing river valley. The 

 discovery of this ancient valley is now announced in a brief paragraph in Nature, 

 of December iith, 1884, and the Btiildej- of December 13th also contains a letter 

 on the subject by Mr. Reade himself. It appears that, at about three hundred 

 yards from the Liverpool side, the upper part of the tunnel intersected for about 

 100 yards a gorge filled with boulder clay and erratics. The clay is hard, and of 

 the usual type of lower boulder clay elsewhere found resting on the Triassic sand- 

 stone. Well-rounded boulders of granite, greenstone, and other travelled rocks 

 were taken out of the clay. The rock through which the tunnel is cut belongs to 

 the ' Pebble Beds ' division of the Bunter Sandstone, and was found to be remark- 

 ably free from faults. 



The pre-glacial valley of the Mersey is now, therefore, an admitted fact, and 

 its discovery affords a very complete proof of the truth of Mr. Reade's theory, sub- 

 mitted over twelve years ago, in the face of a considerable amount of opposition. — 

 O. W. Jeffs, Liverpool. Fa^^^^^, 



