VI  CONTENTS  OF  V()L.   XI. SIXTH   SERIES. 
P; 
Prof.  E.  Rutherford   ou   the   Retardation  of  the  Velocity  of 
the  a  Particles  in  passing  through  Matter 553 
Prof.   A.  W.   Porter   on    the   Inversion-Points   for  a  Fluid 
passing  through  a  Porous  Plug  and  their  use  in   Testing 
Proposed  Equations  of  State 554 
Mr.  R.   Hargreaves   on   some  Ellipsoidal  Potentials,  iEolo- 
tropic  and  Isotropic 568 
Mr.  A.  S.  Eve  on  the  Absorption  of  the  y  Rays  of  Radio- 
active Substances 586 
Mr.  P.   S.   Barlow  on   the   Osmotic  Pressures  of  Alcoholic 
Solutions     595 
Prof.  J.  H.  Jeans  on  the  Constitution  of  the  Atom 604 
Profs.   Wiillner  and   Wien  on  the  Dielectric    Strain   along 
the  Lines  of  Force     607 
Mr.  R.  Chartres  on  "  Minimum  Deviation  through  a  Prism/'  609 
Notices  respecting  New  Books  : — 
Mr.  W.  C.  D.  Whetham's  The  Theory  of  Experimental 
Electricity 610 
Prof.  A.  Righi's  La  Theorie   Moderne  des   Phenomenes 
Physiques  :  Radioactivite,  Ions,  Electrons 610 
Prof.  Ossian  Aschan's  Cheuhe  der  Alicyklischen  Verbind- 
ungen 611 
Prof.  E.  C.  C,  Baby's  Spectroscopy 611 
The  Science  Year-Book     612 
Prof.  Dr.  H.  Kobold's  Der  Ban  des  Fixsternsystems .  .  .  .  613 
Dr.  G.  F.  Lipps's  Die  Psychischen  Massmethoden  ....  613 
Mr.  E.  A.  Black's  Terrestrial  Magnetism  and  its  Causes.  614 
Messrs.  C.  R.  Mann  and  G.  R.  Twiss's  Physics     614 
Proceedings  of  the  Geological  Society  :  — 
Messrs.  T.  C.  Cantrill  and  H.  H.  Thomas  on  the  Igneous 
and  Associated  Sedimentary  Rocks  of  Llangynog.  .  .  .    614 
Mr.  R.  H.  Rastall  on   the  Buttermere   and   Ennerdale 
Granophyre    615 
Prof.  S.  H.  Reynolds   on  the  Igneous    Rocks    of   the 
Eastern  Mendips 616 
NUMBER  LXV.— MAY. 
Prof.  "W.  H.  Bragg  on  the  Ionization  of  Various  Gases  by 
the  a  Particles  of  Radium     617 
Mr.  W.  Hawthorne  and  Prof.  W.  B.  Morton  on  the  Deflexions 
caused  by  a  Break  in  an  Overhead  Wire  carried  on  Poles. .    632 
Mr.  J.  K.  H.  Ingiis  on  the  Isothermal  Distillation  of  Nitro- 
gen and  Oxygen  aud  of  Argon  and  Oxygen    640 
Prof.  J.  A.  Fleming  on  the  Construction  and  Use  of  Oscilla- 
tion Valves  for  Rectifying  High-Frequency  Electric 
Currents     659 
Mr.  G.  B.  Dyke  on  the  Use  of  the  Cymometer  for  the  De- 
termination of  Resonance-Curves     66d 
