Excerpt from Glaciers of North America: A Reading Lesson for Students of Geography and Geology Until within the past few years, nearly all current knowledge of glaciers was based on 'the study of those of the Alps. Practically all theories of the origin, growth, motion, etc., of glaciers were inspired from the same source. An enlargement of the field of study, however, has shown not only that glaciers of the same type as those of Switzerland exist in many other lands, but in numerous instances are larger and present greater diversity; and besides, additional types or "genera" have been discovered that are not represented in Europe or in fact on any of the three continents of the Eastern Hemisphere. As geological and geographical explorations have been extended, it has been found that North America is not only a favorable field for the growth of these twin sciences, bat in many ways furnishes the best example of continental development that has as yet been studied. Strange as it may appear in the face of the overshadowing popular interest that centers in the glaciers of the Alps, North America offers more favorable conditions for the study of existing glaciers and of the records of ancient ice sheets than any other continent. Of each of the three leading types of glaciers thus far reorganized, namely, the alpine, piedmont, and continental, North America furnishes magnificent examples. In fact there is no other continent, except the little known region about the South Pole, in which other than the alpine type of glaciers exist. Of alpine glaciers representatives occur in North America in abundance and in great variety, ranging from the "pocket editions" about the summits of the High Sierra, California, to the magnificent Seward glacier, Alaska, the largest river of ice flowing from a mountain group that has yet been discovered. 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.

Non-technical. Includes information on glaciers, glacial geology, chronology and theories of ice ages.

John K. DeLaski, M.D. practiced medicine in the Penobscot Bay region of Maine and, in addition, was a naturalist with keen powers of observation. His study of the landscape led to the conclusion that a thick glacier had overtopped the highest hills, flooded all of Penobscot Bay, extended far to the east and west and probably was part of a greater continental glacier. He published these very critical field observations and inferences in numerous articles in local newspapers and magazines, and in the American Journal of Science in 1864. His work put him on the “team” of Benjamin Silliman, James D. Dana and Louis Agassiz as an advocate for glaciation as the regional land shaping force opposed to that of the Biblical Deluge, a major scientific conflict of the day both in North America and Europe. He remained a shadowy player, in the background, but clearly contributed critical observations to the argument through personal interactions with Agassiz and other prominent naturalists. They incorporated DeLaski’s observations into their own presentations, often without giving him credit. John DeLaski’s summary work, a 400 page handwritten manuscript for the book, “The Ancient Great Glacier of North America”, was dated 1869. He died in 1874 and the book was not published. The historic significance of DeLaski’s unpublished book is based upon its startling contribution to one of the major scientific questions of the day of whether the surficial geology of northern U.S. and Canada was caused by the actions of the Biblical Flood or by continental glaciation. If published, this would have been the first book on this continent, at least, to present a holistic discussion of the controversy in which he presented his critical observations of the surficial geology in Maine, southern New England and New Brunswick, Canada and concluded that these depositional and erosional features must be of glacial origin. DeLaski then incorporated other evidence into the book for glaciation reported by others from the region during a decade or two, and from the mid and far west and Canada to advocate that the entire region was covered by an ice sheet that was at least 5,000 feet and probably much thicker over interior northern U.S. and Canada and which terminated along a glacial margin which extended from southern new England as far westward along the courses of the Ohio, and Missouri Rivers. All this was done while most “naturalists” still advocated the Biblical Flood to explain the major components of the surficial geology in North America and abroad. DeLaski’s book containing his critical observations of clearly so many landscape features of glacial origin, if published would have been a pivotal document that would have strongly supported those arguing for glaciations in the glaciations vs. flood international argument.