﻿Belatlon 
  heticeen 
  Uranium 
  and 
  Radiiun. 
  857 
  

  

  VII. 
  Xeic 
  E.vperiments. 
  

  

  Two 
  new 
  experiments 
  are 
  being 
  commenced 
  which 
  it 
  is 
  

   hoped 
  will 
  yield 
  in 
  the 
  course 
  of 
  time 
  further 
  evidence 
  on 
  

   the 
  existence 
  or 
  otherwise 
  of 
  short-lived 
  intermediate 
  bodies 
  

   in 
  the 
  series. 
  In 
  the 
  first 
  the 
  purest 
  fraction 
  of 
  the 
  50 
  

   kilograms 
  of 
  uranyl 
  nitrate 
  which 
  has 
  been 
  repeatedly 
  

   crvstallized 
  from 
  fresh 
  w*ater 
  in 
  the 
  work 
  on 
  the 
  7-ravs 
  of 
  

   uranium 
  (Soddy 
  and 
  Russell, 
  Phil. 
  Mag. 
  Oct. 
  1909, 
  p.'620) 
  

   has 
  been 
  withdrawn 
  from 
  the 
  fractionation 
  and 
  sealed 
  up 
  in 
  

   a 
  flask. 
  It 
  contains 
  3 
  kilograms 
  of 
  uranium 
  (element), 
  which 
  

   is 
  12 
  times 
  the 
  quantity 
  in 
  the 
  oldest 
  preparation. 
  It 
  is 
  

   being 
  tested 
  at 
  monthly 
  intervals 
  for 
  growth 
  of 
  radium. 
  The 
  

   initial 
  quantity 
  present 
  has 
  been 
  determined 
  in 
  two 
  agreeing 
  

   consecutive 
  experiments 
  to 
  be 
  42 
  units. 
  Considering 
  the 
  

   mass 
  of 
  the 
  material 
  this 
  is 
  gratifyingly 
  low. 
  In 
  the 
  course 
  

   of 
  a 
  year 
  or 
  two 
  the 
  growth 
  of 
  radium 
  from 
  this 
  solution 
  

   should 
  settle 
  the 
  question 
  whether 
  new 
  intermediate 
  products 
  

   exist 
  in 
  the 
  series. 
  

  

  Secondly, 
  now 
  that 
  the 
  rest 
  of 
  the 
  50 
  kilograms 
  of 
  uranyl 
  

   nitrate 
  has 
  been 
  repeatedly 
  purified, 
  it 
  is 
  proposed 
  to 
  seal 
  up 
  

   one 
  of 
  the 
  preparations 
  of 
  uranium 
  X 
  to 
  be 
  separated 
  from 
  

   it, 
  as 
  in 
  the 
  work 
  with 
  Mr. 
  Russell, 
  and 
  to 
  measure 
  from 
  it 
  

   the 
  rate 
  of 
  production 
  of 
  radium. 
  Unless 
  intermediate 
  bodies 
  

   exist 
  this 
  would 
  hardly 
  be 
  worth 
  while, 
  as 
  it 
  would 
  be 
  prac- 
  

   tically 
  impossible 
  to 
  distinguish 
  the 
  parent 
  of 
  radium 
  formed 
  

   from 
  uranium 
  X 
  — 
  if 
  it 
  is 
  so 
  formed 
  — 
  from 
  that 
  initially 
  sepa- 
  

   rated 
  with 
  the 
  uranium 
  X. 
  Keetmann 
  (Inaug. 
  -Dissert, 
  d. 
  

   Verf., 
  Berlin, 
  1909) 
  has 
  stated 
  that 
  uranium 
  X 
  and 
  the 
  

   parent 
  of 
  radium 
  both 
  have 
  the 
  same 
  chemical 
  properties 
  as 
  

   thorium 
  and 
  cannot 
  be 
  separated 
  from 
  this 
  element 
  or 
  from 
  

   one 
  another. 
  But 
  if 
  an 
  intermediate 
  body 
  exists 
  of 
  period 
  

   of 
  the 
  order 
  of 
  a 
  year 
  it 
  should 
  be 
  easy 
  to 
  distinguish 
  between 
  

   the 
  parent 
  of 
  radium 
  initially 
  present 
  with 
  the 
  uranium 
  X 
  

   and 
  that 
  subsequently 
  produced 
  from 
  it. 
  If 
  U 
  represents 
  

   the 
  quantity 
  of 
  uranium 
  initially 
  in 
  equilibrium 
  with 
  the 
  

   uranium 
  X 
  separated 
  from 
  it, 
  and 
  R 
  represents 
  the 
  quantity 
  

   of 
  radium 
  formed 
  from 
  the 
  uranium 
  X, 
  it 
  can 
  be 
  shown 
  that 
  

  

  assuming 
  the 
  same 
  disintegration 
  series 
  as 
  before. 
  Whereas 
  

   if 
  all 
  the 
  parent 
  of 
  radium 
  were 
  present 
  initially, 
  the 
  pro- 
  

   duction 
  of 
  radium 
  would 
  of 
  course 
  proceed 
  proportionally 
  to 
  

   the 
  time. 
  

  

  