﻿On 
  the 
  Function 
  of 
  the 
  Condenser 
  in 
  an 
  Induction-Coil. 
  447 
  

  

  phenomena 
  in 
  solid 
  bodies, 
  described 
  in 
  the 
  present 
  paper, 
  is 
  

   easily 
  adapted 
  to 
  the 
  study 
  of 
  liquids, 
  and 
  of 
  gases 
  under 
  

   different 
  pressures. 
  

  

  At 
  various 
  intervals 
  during 
  the 
  present 
  century 
  many 
  

   different 
  physicists 
  have 
  been 
  interested 
  in 
  the 
  study 
  of 
  dia- 
  

   magnetism. 
  But 
  notwithstanding 
  the 
  fact 
  that 
  many 
  have 
  

   worked 
  upon 
  the 
  problems 
  which 
  a 
  study 
  of 
  diatnagnetism 
  

   offers, 
  there 
  seem 
  to 
  be 
  some 
  things 
  in 
  connexion 
  with 
  the 
  

   subject 
  which 
  merit 
  more 
  careful 
  investigation. 
  For 
  instance, 
  

   the 
  question 
  as 
  to 
  whether 
  or 
  not 
  a 
  diamagnetic 
  body, 
  after 
  

   being 
  under 
  the 
  influence 
  of 
  a 
  magnetizing 
  force 
  and 
  this 
  

   force 
  withdrawn, 
  requires, 
  if 
  left 
  mechanically 
  undisturbed, 
  a 
  

   "coercive 
  force" 
  to 
  brino- 
  it 
  to 
  the 
  neutral 
  magnetic 
  state 
  

   again, 
  is 
  still 
  an 
  open 
  one. 
  Of 
  course 
  the 
  extreme 
  smallness 
  

   of 
  the 
  action 
  to 
  be 
  measured 
  is 
  the 
  great 
  difficulty 
  en- 
  

   countered 
  in 
  any 
  quantitative 
  work 
  in 
  diamagnetism. 
  

  

  For 
  the 
  illustrations 
  used 
  in 
  this 
  paper 
  I 
  have 
  to 
  thank 
  

   Mr. 
  Joseph 
  Daniels, 
  of 
  the 
  Colorado 
  State 
  Normal 
  School. 
  I 
  

   am 
  under 
  great 
  obligations 
  to 
  Dr. 
  A. 
  G. 
  Webster, 
  Professor 
  

   of 
  Physics 
  at 
  Clark 
  University, 
  for 
  suggestions 
  and 
  advice 
  

   given 
  while 
  the 
  work 
  was 
  being 
  carried 
  out, 
  also 
  to 
  Clark 
  

   University 
  for 
  providing 
  the 
  necessary 
  apparatus. 
  

  

  XLV. 
  On 
  the 
  Function 
  of 
  the 
  Condenser 
  in 
  an 
  Induction-Coil. 
  

   By 
  T. 
  Mizuno, 
  Riyakusld*. 
  

  

  THE 
  efficiency 
  of 
  an 
  induction-coil 
  is 
  greatly 
  increased 
  by 
  

   the 
  employment 
  of 
  a 
  condenser 
  in 
  its 
  primary 
  circuit, 
  in 
  

   accordance 
  with 
  Fizeau's 
  suggestion, 
  but 
  the 
  part 
  played 
  by 
  

   the 
  condenser 
  is 
  not 
  yet 
  clearly 
  known. 
  The 
  most 
  commonly 
  

   accepted 
  opinion 
  is 
  that 
  the 
  extra 
  current 
  in 
  the 
  primary 
  

   circuit, 
  instead 
  of 
  being 
  expended 
  in 
  making 
  a 
  spark 
  at 
  the 
  

   interruptor, 
  darts 
  into 
  the 
  condenser 
  and 
  hastens 
  the 
  decay 
  

   of 
  the 
  primary 
  current, 
  thereby 
  raising 
  the 
  terminal 
  potential- 
  

   difference 
  of 
  the 
  secondary 
  circuit. 
  Moreover, 
  according 
  to 
  

   this 
  view, 
  if 
  a 
  condenser 
  is 
  inserted 
  across 
  the 
  interruptor, 
  

   then 
  on 
  breaking 
  the 
  primary 
  current 
  it 
  continues 
  to 
  run 
  on 
  

   into 
  the 
  condenser 
  for 
  a 
  while; 
  but 
  then 
  rebounds, 
  and 
  is 
  

   reversed 
  in 
  sign, 
  retaining 
  its 
  initial 
  full 
  strength. 
  Hence 
  

   the 
  electromotive 
  force 
  set 
  up 
  in 
  the 
  secondary 
  circuit 
  is 
  the 
  

   joint 
  result 
  of 
  a 
  stoppage 
  of 
  a 
  primary 
  current 
  and 
  its 
  im- 
  

   mediate 
  reversal 
  in 
  direction. 
  But 
  this 
  simple 
  explanation, 
  

   however 
  plausible 
  at 
  first 
  sight, 
  is 
  yet 
  an 
  imperfect 
  account 
  

   of 
  the 
  function 
  of 
  the 
  condenser. 
  In 
  this 
  paper, 
  I 
  propose 
  to 
  

  

  * 
  Communicated 
  by 
  the 
  Author. 
  

  

  2 
  H2 
  

  

  