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Excerpt from The Geology of New Hampshire: A Report Comprising the Results of Explorations Ordered by the Legislature; Surface Geology, Mineralogy and Lithology, Economic Geology The indications of a glacial period abound in all northern countries whose geology has been explored; and in New Hampshire they are prob ably as well shown as in any part of the world. Underlying the modi fied drift we often find masses of earth and rocks mingled confusedly together, without stratification or any appearance of having been depos ited in water. These are the glacial drift or fill. Unlike the modified drift, till is distributed with no reference to lines of drainage, and fre quently covers the slopes or lies at the summits of our highest hills and mountains. The boulders which it contains, or which lie upon its sur face, are of all sizes up to ten feet, or rarely even twenty or thirty feet, in diameter; and in this state they have nearly all been transported south ward from their native ledges. Where an outcrop of rock is so peculiar that its boulders cannot be confounded with those from other ledges, we may trace them southward or south-eastward, but not in other directions. They are abundant near their source, and diminish in numbers and size as we advance. The till of New Hampshire contains boulders which are thus known to have travelled a hundred miles. Wherever till occurs, it is also found that the ledges have been commonly worn to a rounded form; and, if the rock is sufficiently durable, it is covered with long par allel scratches or xii/id, which have the same direction with the dispersal of rocks in the till. The same 'areas are also characterized by extensive deposits of modified drift. 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 wor