﻿664 
  Dr. 
  F. 
  C. 
  Brown 
  on 
  the 
  Kinetic 
  Energy 
  of 
  the 
  

  

  A 
  second 
  series 
  o£ 
  observations 
  were 
  made 
  after 
  a 
  second 
  

   coating 
  o£ 
  the 
  phosphate 
  had 
  been 
  put 
  on 
  by 
  a 
  slightly 
  

   different 
  treatment. 
  The 
  water 
  was 
  allowed 
  to 
  evaporate 
  

   from 
  the 
  paste 
  at 
  room 
  temperature, 
  thus 
  leaving 
  an 
  even 
  

   w^hite 
  coating 
  on 
  the 
  disk. 
  The 
  current 
  was 
  somewhat 
  

   larger 
  than 
  it 
  was 
  in 
  the 
  first 
  trial. 
  The 
  kinetic 
  energy 
  of 
  

   the 
  ions 
  arising 
  from 
  the 
  velocity 
  components 
  perpendicular 
  

   to 
  the 
  surface 
  of 
  the 
  disk, 
  was, 
  within 
  the 
  limits 
  of 
  error, 
  the 
  

   same 
  as 
  it 
  was 
  for 
  the 
  ions 
  from 
  the 
  metals. 
  That 
  aluminium 
  

   phosphate 
  gives 
  a 
  larger 
  positive 
  ionization 
  than 
  do 
  the 
  

   metals 
  was 
  first 
  observed 
  by 
  J. 
  J. 
  Thomson. 
  

  

  Iron, 
  

  

  Capacity, 
  

   micro- 
  

   farads. 
  

  

  Pressure, 
  

  

  mm. 
  

  

  Temperatuj-e, 
  

   absolute. 
  

  

  Initial 
  

  

  Potential, 
  

  

  volts. 
  

  

  Mean 
  

  

  Thermionic 
  

  

  Current 
  in 
  

  

  Arbitrary 
  

  

  Units. 
  

  

  Mean 
  

  

  Potential, 
  

  

  volts. 
  

  

  Value 
  

   ot'R. 
  

  

  •0001 
  

  

  

  1100 
  

  

  

  

  0-1 
  

  

  0^2 
  

  

  03 
  

  

  0-4 
  

  

  21-0 
  

  

  9-7 
  

  

  5-5 
  

  

  2-1 
  

  

  •9 
  

  

  •02 
  

   •12 
  

   •21 
  

   •31 
  

  

  •4 
  

  

  4^6x103 
  

  

  •0001 
  

  

  0005 
  

  

  1100 
  

  

  

  

  01 
  

  

  0-2 
  

  

  0-3 
  

  

  0-4 
  

  

  16-5 
  

  

  51 
  

  

  2-4 
  

   1-1 
  

  

  •017 
  

   •12 
  

   •21 
  

   •3 
  

  

  •4 
  

  

  5-2x103 
  

  

  •01 
  

  

  •01 
  

  

  1240 
  

  

  

  

  0-1 
  

  

  02 
  

  

  0-3 
  

  

  0-4 
  

  

  1400 
  

  

  810 
  

  

  360 
  

  

  170 
  

  

  63 
  

  

  •01 
  

   •10 
  

   •20 
  

   •30 
  

   •40 
  

  

  4-3x10^ 
  

  

  Iron. 
  

  

  The 
  positive 
  ionization 
  from 
  iron 
  was 
  studied 
  in 
  essentially 
  

   the 
  same 
  way 
  as 
  it 
  was 
  from 
  the 
  other 
  elements. 
  A 
  silver 
  

   disk 
  was 
  welded 
  to 
  a 
  platinum 
  heater 
  and 
  the 
  iron 
  disk 
  was 
  

   welded 
  to 
  the 
  silver 
  disk. 
  This 
  device 
  was 
  used 
  mainly 
  for 
  

   convenience. 
  The 
  behaviour 
  was 
  somewhat 
  irregular, 
  but 
  in 
  

   every 
  case 
  the 
  kinetic 
  energy 
  is 
  seen 
  to 
  be 
  larger 
  than 
  the 
  

   normal 
  value 
  3'7 
  x 
  10^. 
  

  

  