Book excerpt: Excerpt from The Theory of Valency IT seems rather remarkable that no treatise Should be extant in our own language on such an important subject as valency. Nor is the German literature in a much better position, for it contains but one monograph on the subject, written by Dr. F. Willy Hinrichsen in 1902. This, though excellent, can scarcely be regarded as exhaustive. Moreover, during the past six years much new material has been collected, and calls for rearrangement and discussion. Perhaps this lack of systematic treatment of the subject is to be ascribed to the difficulty of reconciling any theory of valency with the facts of inorganic chemistry. But the remarkable success which has attended our application of the theory to the study of organic chemistry may be regarded as a guarantee that we are on the right track, and should serve to stimulate us, rather than otherwise, in our attempts to perfect our theory. It has been my endeavour in the present volume to present to the reader a concise account of the more important theories of chemical combination, which have exercised the minds of scientific men down to the present day. 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.