﻿their 
  Sodium 
  Salts 
  on 
  Lupinus 
  Albus. 
  185 
  

  

  concentration 
  as 
  that 
  of 
  HC1, 
  provided 
  ionization 
  were 
  com- 
  

   plete. 
  These 
  suppositions 
  have 
  been 
  practically 
  realized 
  (1). 
  

   We 
  are 
  now 
  able 
  by 
  means 
  of 
  these 
  values 
  to 
  obtain 
  an 
  

  

  expression 
  representing 
  approximately 
  the 
  toxic-value 
  of 
  H 
  

  

  ions. 
  If 
  the 
  molecule 
  splitting 
  off 
  two 
  H 
  ions 
  when 
  com- 
  

   pletely 
  dissociated 
  at 
  the 
  death-limit, 
  gives 
  a 
  value 
  of 
  12,800, 
  

   and 
  the 
  same 
  molecule 
  in 
  which 
  one 
  H 
  is 
  replaced 
  by 
  a 
  metal 
  

   gives 
  one-half 
  that 
  value, 
  plainly 
  all 
  other 
  factors 
  become 
  prac- 
  

   tically 
  zero 
  in 
  comparison 
  with 
  the 
  H. 
  This 
  ion 
  may, 
  there- 
  

   fore, 
  be 
  given 
  approximately 
  the 
  absolute 
  value 
  of 
  6400. 
  We 
  

   see 
  that 
  "all 
  other 
  ions 
  concerned 
  are 
  negligible 
  in 
  comparison 
  

  

  with 
  H 
  ions 
  ; 
  hence 
  K 
  ions 
  and 
  S0 
  4 
  ions 
  have 
  a 
  relatively 
  

  

  insignificant 
  value. 
  If 
  H^ions 
  have 
  a 
  toxic-value 
  of 
  6400, 
  

   plainly 
  in 
  HC1 
  with 
  a 
  toxic-value 
  of 
  6400, 
  the 
  CI 
  ions 
  are 
  rela- 
  

   tively 
  insignificant 
  (1). 
  Results 
  of 
  experiments 
  not 
  yet 
  in 
  

   print 
  have 
  shown 
  that 
  for 
  the 
  lupines 
  the 
  toxic-values 
  of 
  NaCl 
  

  

  and 
  KC1 
  are 
  essentially 
  alike, 
  16, 
  hence 
  Na 
  ions 
  are 
  likewise 
  

   relatively 
  insignificant. 
  

  

  The 
  question 
  now 
  arises, 
  what 
  is 
  the 
  actual 
  significance 
  of 
  

   the 
  relatively 
  weak 
  factors, 
  the 
  anions 
  and 
  the 
  undissociated 
  

  

  molecules? 
  Since 
  the 
  sum 
  of 
  the 
  toxic-values 
  of 
  Na 
  ions^ 
  CI 
  

   ions 
  and 
  15 
  per 
  cent 
  undissociated 
  molecules 
  equals 
  16, 
  plainly 
  

   no 
  one 
  factor 
  can 
  have 
  a 
  value 
  exceeding 
  16. 
  Probably 
  any 
  

   one 
  of 
  them 
  is 
  considerably 
  less. 
  For 
  the 
  present, 
  however, 
  it 
  

  

  is 
  sufficient 
  to 
  know 
  that 
  the 
  toxic-value 
  of 
  Na 
  ions 
  and 
  the 
  

  

  toxic-value 
  of 
  CI 
  ions 
  is 
  each 
  less 
  than 
  16, 
  or 
  less 
  than 
  ^-i-^that 
  

  

  + 
  

   of 
  H 
  ions. 
  

  

  In 
  the 
  discussion 
  of 
  the 
  toxic-values 
  of 
  the 
  compounds 
  here 
  

   concerned, 
  I 
  shall 
  try 
  to 
  fix, 
  as 
  accurately 
  as 
  may 
  be, 
  the 
  par- 
  

   tial-toxicity 
  due 
  to 
  each 
  factor. 
  

  

  Discussion 
  of 
  Results. 
  — 
  In 
  order 
  to 
  present 
  in 
  as 
  clear 
  a 
  

   manner 
  as 
  possible 
  the 
  results 
  of 
  greatest 
  significance 
  in 
  this 
  

   discussion, 
  I 
  have 
  omitted 
  the 
  details 
  of 
  the 
  individual 
  experi- 
  

   ments, 
  only 
  indicating 
  their 
  outcome. 
  In 
  the 
  tables, 
  as 
  well 
  as 
  

   in 
  the 
  discussion 
  of 
  data, 
  the 
  toxic-values 
  are 
  expressed 
  by 
  the 
  

   numbers 
  of 
  liters 
  of 
  water 
  in 
  which 
  the 
  molecular-weight 
  in 
  

   grams, 
  of 
  the 
  substances 
  concerned, 
  must 
  be 
  dissolved, 
  to 
  give 
  

   the 
  physiological 
  results 
  seen. 
  The 
  same 
  numbers 
  would 
  occur 
  

   as 
  the 
  denominators 
  of 
  the 
  fractions 
  indicating 
  those 
  parts 
  of 
  a 
  

   gram-molecule 
  which, 
  dissolved 
  in 
  one 
  liter 
  of 
  water 
  each, 
  

   would 
  form 
  the 
  strongest 
  concentrations 
  in 
  which 
  the 
  primary 
  

   radicles 
  of 
  Lwjpinus 
  albus 
  could 
  survive 
  for 
  twenty-four 
  hours. 
  

  

  