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XXXIV. Sketch of a Stratigraphical Table, chiefly for Western 

 Europe. By John Young, M.D., Professor of Natural 

 History and Honyman Gillespie Lecturer on Geology in 

 Glasgow University* . 



THE accompanying table is an attempt to apply and extend 

 the philosophical principle underlying a remark made 

 many years ago by Sir A. C. Ramsay, that the Carboniferous 

 Limestone was an episode in British Geology. I discussed 

 the matter tentatively in 1876 (Brit. Assoc. Report, Glasgow, 

 Address to Section C), and now submit a fuller scheme. The 

 geology of Western Europe is the record of a border warfare 

 between the Atlantic on the one hand and the Europeo- 

 Asiatic continent on the other, the advance and retreat of 

 ocean and land giving rise to a series of dissolving geo- 

 graphical views, not one of which can be definitely fixed. 

 Of ocean and of continent we have little knowledge : of the 

 debatable line between them our whole geological knowledge 

 is made up. The index map of colours published by the 

 Geological Survey is commonly made the basis of calculations 

 of geological time, as if every superposed block of colour 

 represented a distinct epoch. My table is an attempt to 

 put in new shape the common stock of geological teachers, 

 that land and sea are contemporaneous, and that a true 

 narrative should not place all the strata of one region — say, 

 Western Europe — on the top of each other, but should allow 

 for the contemporaneous occurrence of sea and land, of thick 

 and of thin deposits, on the inclined plane from the coast down 

 to the floor of the adjacent sea. Sir A. C. Ramsay gave to 

 Mr. Darwin a summary statement of British Geology, from 

 which it seemed a fair arithmetical inference that the thickness 

 of the sedimentary crust is 20 miles. I do not know for 

 what purpose that statement was prepared ; but I do know 

 that it has been used by subsequent writers as if the " onion- 

 coat theory of the earth's crust " (to use Herbert Spencer's 

 graphic phrase) were still accepted. The right-hand side 

 of my table is that of the permanent land-area, the left that 

 of the permanent Atlantic Ocean. The left column shows 

 the successive incursions of the ocean ; the right column 

 indicates the periods during which elevation carried the land, 

 in whole or in part, to or towards the present western 

 confines of Europe; in the interval are recorded the estuarine 

 and fluvio-lacustrine conditions. I need not point out in 

 detail how such a table tends to demonstrate that the duration 



* Communicated by the Author. 



