Excerpt from Petralogy, Vol. 2: A Treatise on Rocks Such were the reasons for the preference of this areary term to any other arbitrary term, and as it cannot be too often repeated that the chief use of any system of natural history 15 to assist the memory, it will perhaps be difficult to find a term less objectionable; at least, though the plan has been deeply reconsidered for many years, none such has arisen to the author: but perhaps candid disquisition, and literary collision, may produce some more appropriate appellation. 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.