ONTENTS   OF  VOL.  XL 
(SIXTH  SERIES). 
;er  lxi.-januaet  1906. 
Page 
fep  Sea  Ship-Waves   1 
on   an    Expeditious  Practical  Method  of 
Harmonic  Analysis.     (Plate  I.) 25 
Mr.  L.  R.  Ingersoll  on  the  Faraday  and  Kerr  Effects  in  the 
Infra-red  Spectrum 4i 
Mr.  V.  H.  Yeley  on  a  Modified  Form  of  Apparatus  for 
the  Determination  of  the  Dielectric  Constants  of  Non- 
Conducting  Liquids , 73 
Dr.  W.  E.  Sumpner  on  the  Theory  of  Phasemeters 81 
Prof.  J.  Perry  on  Winding  Ropes  in  Mines.     (Plate  II.).  .  .  .    107 
Lord  Rayleigh  on  Electrical  Vibrations  and  the  Constitution 
of  the  Atom 117 
Lord  Rayleigh  on  the  Constitution  of  Natural  Radiation. .  .  .    123 
Lord  Kayleigh  on  an  Instrument  for  Compounding  Vibrations, 
with  application  to  the  drawing  of  Curves  such  as  might 
represent  White  Light.     (Plate  III.) 127 
Mr.  R.  K.  McClung  on  the  Absorption  of  a  Rays     131 
Dr.  H.  L.  Bronson  on  the  Effect  of  High  Temperatures  on 
the  Rate  of  Decay  of  the  Active  Deposit  from  Radium    .  .    143 
Mr.  A.  B.  Porter  on  the  Diffraction  Theory  of  Microscopic 
Vision 154 
Prof.  E.  Rutherford  on  some  Properties  of  the  a  Rays  from 
Radium.     (Plate  IV.) 166 
Prof.   H.  N.   McCoy  on   the  Relation   between  the  Radio- 
activity and  the  Composition  of  Uranium  Compounds  ....    170 
Notices  respecting  New  Books  : — 
Transactions  of   the   International   Electrical   Congress. 
St.  Louis,  1904 L86 
von  Neumayer's  Anleitung  zu  wissenschaftlichen    Beo- 
bachtungen  auf  Reisen      L87 
Annuaire  pour  l'An  1906     ls7 
Proceedings  of  the  Geological  Society  : — 
Prof.  E.   11.  L.  Schwarz   o}\  the   Coast-Ledges    in    the 
South- West  of  the  Cape  Colony L88 
