:c^i THE ELEMENTS OF PHYSICS Digitized by the Internet Archive 2010 in http://www.archive.org/details/elementsofphys1938smit Plate of Spectra 80 75 70 65 60 55 50 45 40 THE ELEMENTS OF PHYSICS BY ALPHEUS W. SMITH, Ph.D. Professor ofPhysics, The Ohio State University Fourth Edition McGRAW-HILL BOOK COMPANY, Inc. NEW YORK AND LONDON 1938 Copyright, 1923, 1927, 1932, 1938, by the McGraw-Hill Book Company, Inc. PRINTED IN THE UNITED STATES OF AMERICA All rights reserved. This book, or partsthereof,maynotbereproduced in anyform without permission of the publishers. THE MAPLE PRESS COMPANY, YORK, PA.