An Estimate of Post-Glacial Time

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Of late several attempts have been made to show that the close of the Glacial period was very recent. Having personally devoted considerable attention to what is called Post-glacial or “superficial” geology, I am much struck with the imperfect knowledge with which the question of Post-glacial time is frequently approached. The writers seem to be unaware of, or to insufficiently appreciate, the grand sequence of events recorded in the deposits on the Lancashire and Cheshire coasts which have taken place since the snow and ice of the Glacial period disappeared. On the borders of the coast-line between the Dee, the Mersey, and the Ribble, the student who cares to pursue the subject can do so with great advantage. But through the horizontality of the deposits, and their general low level, none occurring above the level of the 25 feet Ordnance datum and all reaching down to below the level of the lowest spring-tides, the study has to be pursued through the medium of excavations and borings. This I have done in observations extending over many years, and I now propose to show their bearing upon the absorbing question of recent geological time. Denudation of the Low-Level Marine Boulder-clay. The whole of the country to which these notes specially refer was formerly entirely covered with a mantle of Low-level marine Boulder-clay and sands. These I have described at length in several papers. That the valleys of the Dee, Mersey, and Ribble were at one time filled with Low-level marine Boulder-clay, we