Excerpt from Practical Orthodontia In addition to those who contributed to the third edition of this work, the author is indebted to Dr. Lloyd S. Lourie for illustrations used to elucidate the technique of the lingual appliance and the high labial arch with spring extensions; to Dr. John V. Mershon, of the University of Pennsylvania, for suggestions in the use of the removable lingual arch with finger springs; and to Dr. W. W. Martin, of the University of Iowa, for his faithful cooperation in working out in clinical practice some of the mechanical principles. An effort on the part of the author has been made to limit the book to such principles as have proved of value in practice, and it is hoped that this edition will render as great a service to orthodontists, students. 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.