﻿CONTENTS 
  OF 
  VOL. 
  XVI. 
  STXTH 
  SERIES. 
  Vll 
  

  

  NUMBER 
  XCVI.— 
  DECEMBER. 
  

  

  Page 
  

  

  Prof. 
  C. 
  A. 
  Skinner 
  and 
  Mr. 
  A. 
  Q. 
  Tool 
  : 
  An 
  Investigation 
  

   of 
  the 
  Optical 
  Properties 
  of 
  Films 
  of 
  Magnetic 
  Metals. 
  

   (Plate 
  XXIV.) 
  833 
  

  

  Mr. 
  B.W. 
  Clack 
  on 
  the 
  Coefficient 
  of 
  Diffusion. 
  (Plate 
  XXY.) 
  863 
  

  

  Messrs. 
  T. 
  H. 
  Laby 
  and 
  Gr. 
  W. 
  C. 
  Kaye 
  on 
  Graseous 
  Ioniza- 
  

   tion 
  and 
  Pressure. 
  (Plate 
  XXVI.) 
  . 
  . 
  . 
  , 
  „ 
  879 
  

  

  Prof. 
  0. 
  TV. 
  Richardson 
  on 
  the 
  Kinetic 
  Energy 
  of 
  the 
  Ions 
  

   emitted 
  by 
  Hot 
  Bodies 
  890 
  

  

  Mr. 
  J. 
  J. 
  Taudin 
  Chabot 
  on 
  a 
  Rotating 
  Earth-iuductor 
  without 
  

   Sliding 
  Contacts. 
  (Plate 
  XXVII.) 
  916 
  

  

  Prof. 
  TV. 
  H. 
  Bragg 
  and 
  Mr. 
  J. 
  P. 
  V. 
  Madsen 
  : 
  An 
  Experi- 
  

   mental 
  Investigation 
  of 
  the 
  Nature 
  of 
  y 
  Rays 
  918 
  

  

  Dr. 
  A. 
  H. 
  Bucherer 
  on 
  the 
  Principle 
  of 
  Relativity. 
  * 
  A 
  Reply 
  

   to 
  Mr. 
  E. 
  Cunningham 
  '. 
  939 
  

  

  Prof. 
  R. 
  "W. 
  Wood 
  on 
  a 
  Method 
  of 
  Showing 
  Fluorescent 
  

   Absorption 
  directly 
  if 
  it 
  exists 
  940 
  

  

  Prof. 
  R. 
  W. 
  Wood 
  on 
  an 
  Extension 
  of 
  the 
  principal 
  Series 
  

   of 
  the 
  Sodium 
  Spectrum. 
  (Plate 
  XXVIII.) 
  ' 
  945 
  

  

  Mr. 
  P. 
  W. 
  Bridgmau 
  on 
  a 
  Certain 
  Development 
  in 
  Bessel's 
  

   Punctions 
  , 
  . 
  . 
  947 
  

  

  Mr. 
  W. 
  W. 
  Campbell 
  on 
  the 
  Rings 
  of 
  Saturn 
  949 
  

  

  Dr. 
  G-. 
  Johnstone 
  Stoney 
  on 
  Telescopic 
  Vision. 
  — 
  Part 
  III.. 
  . 
  950 
  

  

  Index 
  980 
  

  

  ERRATA. 
  

  

  Page 
  519, 
  line 
  20, 
  for 
  few 
  cubic 
  centimetres 
  read 
  few 
  cubic 
  millimetres. 
  

   Page 
  520, 
  line 
  4 
  from 
  bottom, 
  for 
  glass 
  read 
  gas. 
  

  

  