*Frontmatter, pg. i*PREFACE, pg. v*TABLE OF CONTENTS, pg. xi*CHAPTER I. DEFINITIONS, METHODS AND RESULTS, pg. 1*CHAPTER II. THE PRINCIPLES OP DIRICHLET AND THOMSON, pg. 42*CHAPTER III. APPLICATIONS OP THE PRINCIPLES OP DIRICHLET AND THOMSON TO ESTIMATION OP THE CAPACITY, pg. 63*CHAPTER IV. CIRCULAR PLATE CONDENSER, pg. 79*CHAPTER V. TORSIONAL RIGIDITY AND PRINCIPAL FREQUENCY, pg. 87*CHAPTER VI. NEARLY CIRCULAR AND NEARLY SPHERICAL DOMAINS, pg. 127*CHAPTER VIII. ON ELLIPSOID AND LENS, pg. 171*NOTE A. SURFACE-AREA AND DIRICHLET'S INTEGRAL, pg. 182*NOTE B. ON CONTINUOUS SYMMETRIZATION, pg. 200*NOTE C. ON SPHERICAL SYMMETRIZATION, pg. 205*NOTE D. ON A GENERALIZATION OF DIRICHLET'S INTEGRAL, pg. 211*NOTE E. HEAT-CONDUCTION ON A SURFACE, pg. 217*NOTE F. ON MEMBRANES AND PLATES, pg. 230*NOTE G. VIRTUAL MASS AND POLARIZATION, pg. 239*TABLES FOR SOME SET-FUNCTIONS OF PLANE DOMAINS, pg. 247*BIBLIOGRAPHY, pg. 275*LIST OF SYMBOLS, pg. 278