﻿Chemistry 
  and 
  Physics. 
  61 
  

  

  plate 
  of 
  ice 
  was 
  almost 
  entirely 
  free 
  from 
  air 
  bubbles. 
  Accord- 
  

   ing 
  to 
  this, 
  ice 
  does 
  not 
  present 
  exceptional 
  dielectric 
  properties. 
  

  

  It 
  remains 
  to 
  be 
  explained 
  how 
  MM. 
  Bouty 
  and 
  A. 
  Perot 
  ob- 
  

   tained 
  values 
  of 
  a 
  totally 
  different 
  order 
  for 
  the 
  dielectric 
  power 
  

   of 
  ice. 
  In 
  the 
  first 
  place, 
  in 
  M. 
  Bouty's 
  method 
  the 
  charge 
  and 
  

   discharge 
  were 
  enormously 
  slower 
  than 
  in 
  my 
  experiments. 
  Is 
  it 
  

   not 
  probable, 
  then, 
  that 
  the 
  physical 
  magnitudes 
  measured 
  by 
  

   31. 
  Bouty 
  and 
  myself 
  were 
  in 
  themselves 
  very 
  different. 
  In 
  any 
  

   case 
  we 
  know 
  at 
  present 
  too 
  little 
  about 
  the 
  dielectric 
  properties 
  

   of 
  bodies 
  to 
  be 
  surprised 
  at 
  the 
  divergences 
  of 
  numbers 
  obtained 
  

   by 
  two 
  methods 
  so 
  dissimilar, 
  however 
  great 
  they 
  are. 
  — 
  Comptes 
  

   Pendus, 
  October 
  8, 
  1894. 
  — 
  Phil. 
  Mag., 
  xxxviii, 
  578, 
  Dec, 
  1894. 
  

  

  8. 
  Potation 
  of 
  magnetic 
  lines. 
  — 
  E. 
  Lecher 
  describes 
  in 
  the 
  

   Wiener 
  Berichte 
  an 
  experiment 
  performed 
  to 
  test 
  whether, 
  

   when 
  a 
  magnet 
  turns 
  about 
  its 
  magnetic 
  axis, 
  the 
  lines 
  of 
  force 
  

   remain 
  at 
  rest 
  or 
  turn 
  w 
  r 
  ith 
  the 
  magnet. 
  A 
  magnet 
  was 
  divided 
  

   by 
  an 
  equatorial 
  plane 
  into 
  two 
  parts 
  which 
  could 
  turn 
  inde- 
  

   pendently. 
  It 
  was 
  possible 
  to 
  obtain 
  from 
  the 
  two 
  extremities 
  

   of 
  the 
  magnet 
  an 
  induced 
  current 
  of 
  such 
  a 
  magnitude 
  as 
  cannot 
  

   be 
  explained 
  by 
  the 
  cutting 
  of 
  the 
  rotating 
  lines 
  of 
  force 
  by 
  the 
  

   extremely 
  short 
  brushes 
  employed. 
  These 
  currents 
  can 
  be 
  ex- 
  

   plained 
  if 
  we 
  suppose 
  that 
  a 
  rotating 
  magnet 
  cuts 
  its 
  own 
  lines 
  of 
  

   force 
  which 
  remain 
  fixed 
  in 
  space. 
  — 
  Nature, 
  Nov. 
  22, 
  1894, 
  p. 
  84. 
  

  

  J. 
  T. 
  

  

  9. 
  Magnetization 
  of 
  iron 
  and 
  nickel 
  icire. 
  — 
  Klemencic 
  has 
  

   measured 
  the 
  permeability 
  of 
  iron 
  steel 
  and 
  nickel 
  wire 
  with 
  the 
  

   rapidly 
  alternating 
  currents 
  employed 
  by 
  Hertz. 
  He 
  employed 
  

   the 
  method 
  of 
  a 
  thermal 
  junction 
  previously 
  described 
  by 
  him 
  and 
  

   obtains 
  the 
  following 
  values. 
  

  

  Soft 
  iron 
  _ 
  jj. 
  .— 
  1 
  1 
  8 
  

  

  Hard 
  steel... 
  /-t 
  = 
  1 
  15 
  

  

  Bessemer 
  steel 
  ywr= 
  77 
  

  

  Nickel 
  ._. 
  jj.= 
  27 
  

  

  — 
  Ann. 
  der 
  Physik 
  und 
  Chemie,~No. 
  12, 
  pp. 
  705-720. 
  J. 
  t. 
  

  

  10. 
  New 
  Storage 
  Battery. 
  — 
  In 
  researches 
  on 
  the 
  condensation 
  of 
  

   electrolytic 
  gases 
  by 
  porous 
  bodies, 
  particularly 
  by 
  metals 
  of 
  the 
  

   platinum 
  group, 
  M. 
  L. 
  Caillelet 
  and 
  E, 
  Collardeau 
  find 
  

   that 
  platinum 
  and 
  palladium 
  in 
  the 
  spongy 
  condition 
  and 
  ruthe- 
  

   nium, 
  iridium 
  and 
  gold 
  in 
  the 
  finely 
  divided 
  state 
  form 
  poles 
  

   which 
  condense 
  electrolytic 
  gases 
  and 
  hence 
  produce 
  a 
  gas 
  

   battery, 
  wirich 
  on 
  connection 
  of 
  the 
  poles 
  is 
  capable 
  of 
  giving 
  up 
  

   the 
  stored 
  energy 
  for 
  a 
  short 
  period. 
  The 
  storage 
  capacity 
  is 
  

   vastly 
  increased 
  by 
  subjecting 
  the 
  poles 
  to 
  great 
  pressure 
  during 
  

   charging. 
  With 
  spongy 
  platinum 
  and. 
  iridium 
  a 
  storage 
  capacity 
  

   can 
  be 
  obtained 
  which 
  is 
  greater 
  than 
  the 
  capacity 
  of 
  lead 
  ac- 
  

   cumulators 
  per 
  unit 
  of 
  weight. 
  With 
  finely 
  divided 
  palladium, 
  a 
  

   storage 
  capacity 
  of 
  176 
  ampere-hours 
  per 
  kilograms 
  of 
  palladium 
  

   was 
  obtained 
  at 
  a 
  pressure 
  of 
  600 
  atmospheres. 
  The 
  storage 
  

   capacity 
  of 
  an 
  ordinary 
  lead 
  accumulator 
  is 
  about 
  15 
  ampere- 
  

   hours 
  per 
  kilogram 
  of 
  lead. 
  — 
  Comptes 
  Pendus, 
  Nov. 
  12, 
  1894. 
  

  

  J. 
  T. 
  

  

  