Book Description

Excerpt from Preliminary Report on the Limestones and the Lime Industry of Manitoba According to origin, limestone may be divided into two classes: (1) sedimentary, including those formed in either marine or fresh water either by chemical or organic agents, (2) crystal line, including those formed by metamorphic action (heat, pres sure and water) from sedimentary limestone or from igneous rocks such as anorthosites, pyroxenites, etc. All of the limestones having any industrial value in Manitoba are of sedimentary origin, and when the term limestone is hereafter mentioned it refers to the sedimentary variety unless otherwise specified. It is impossible in this report to discuss the different methods by which limestone has been or is being formed under natural conditions. The calcareous remains of organisms such as the corals, molluscs and the foraminifera have been the chief source of lime stone by having their shells ground to a calcareous slime before deposition. A deposit of cretaceous limestone on the banks of the Assiniboine River consists of crushed oyster shells cemented into a hard, gray limestone. Those laid down by chemical precipitation in deep water, such as in Upper Devonian periods, are likely to be quite pure, while those laid down from concentrated solutions are likely to contain magnesia, for example, the dolomites of the Niagara for mation in the Silurian period. 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.