Excerpt from The Principles of Pathologic Histology If the injurious agent is within the circulation, the reaction between it and the elements of the blood takes place there. Under this condition the resulting injury is usually difficult or impossible of demonstration, because it may have been produced only on the elements of the blood, and the, reaction is so generally distributed in the circulation that often little or no effect is visible. When, however, the injurious agent is outside of the circula tion, it is usually rather sharply localized in one focus or another, and the injury is often marked. The elements of the blood, in order to reach the injurious agent, must escape from the blood vessels. As a result they accumulate in the affected area, and in this way striking lesions are often produced. 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.