Excerpt from Second Book in Physiology and Hygiene All cells are active workers; and each has its special work to do. The human body may be aptly compared to a community made up of multitudes of individuals. In most communities there are various classes of workers - carpenters, blacksmiths, jewellers, chemists, merchants, teachers, etc. In the body, likewise, there is a division of labor. Some cells build, others tear down. Some cells may be compared to artists, others do the work Of scavengers. Some construct solid parts, others make the various fluids to be employed in the body or to be removed from it. Some act as sentinels, to give the body warning of danger; others defend it when attacked by the enemies of life or health. All labor together in the most perfect harmony when their work is not in any way interfered with. 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.

This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work. This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work. As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.