The Geology of the Land's End District (Classic Reprint)

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Excerpt from The Geology of the Land's End District The geological map accompanying this memoir combines the land-areas represented by Sheets 351 and 358 of the new series one-inch map. The original survey of the district was made by Sir H. T. De la Beche, and the results were published in 1839 on the old series one-inch map, Sheet 33. In the earlier issues of this Sheet the slaty rocks (killas) were simply coloured Grauwacke, but in the later issues from about 1846 onwards the rocks in question were coloured Devonian. Additional lodes were inserted by Sir W. W. Smyth on a revised edition of Sheet 33, which appeared in 1866. On comparing the old map with the map to which this memoir refers, it will be seen that one of the most important differences is the reference of the slaty rocks to the Lower Palæozoic period and their subdivision into three groups, to which the terms Portscatho, Falmouth and Mylor have been applied. No characteristic fossils have been found in these rocks, so that some doubt as to their age may still remain, for the reasons that have led to the classification which has been adopted, the reader is referred to the memoirs on Sheets 352 (Falmouth) and 353 (Mevagissey), and to a paper by Mr. Hill on 'The Older and Newer Palæozoics of West Cornwall' (Geol. Mag., 1906, p. 206). The literature of the district is very extensive, especially in the departments of mining and mineralogy. In mining we are largely indebted to Henwood, De la Beche, W. W. Smyth, R. Hunt, Le Neve Foster, Mr. J. H. Collins, J. Arthur Phillips, and Prof. H. Louis. In mineralogy the list of writers is too numerous to quote. For more than 200 years the district has attracted the attention of collectors and mineralogists, and in every good collection of British minerals a large number of rare and beautiful specimens that have been obtained from it will be found. To Samuel Allport and J. A. Phillips we are indebted for important papers on the microscopic structure of certain rocks, and to Mr. J. H. Collins for similar papers on Tinstones and Capels. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully, any imperfections that remain are intentionally left to preserve the state of such historical works.