﻿PHOTOSYNTHESIS 
  BALY 
  243 
  

  

  There 
  is 
  yet 
  another 
  striking 
  feature 
  which 
  is 
  common 
  to 
  the 
  

   two, 
  photosynthesis 
  in 
  vivo 
  and 
  in 
  vitro. 
  The 
  hght 
  must 
  not 
  be 
  too 
  

   strong 
  in 
  either, 
  for 
  if 
  it 
  is 
  too 
  strong 
  then 
  harmful 
  results 
  at 
  once 
  

   supervene. 
  This 
  is 
  due 
  to 
  the 
  poisoning 
  of 
  the 
  surface 
  by 
  the 
  

   oxygen 
  which 
  is 
  set 
  free. 
  In 
  both 
  cases 
  this 
  poisoning 
  slowly 
  rights 
  

   itself, 
  and 
  in 
  both 
  the 
  synthesis 
  must 
  not 
  proceed 
  at 
  a 
  greater 
  rate 
  

   than 
  that 
  of 
  the 
  recovery 
  of 
  the 
  surface 
  from 
  its 
  poisoning. 
  

  

  In 
  fine, 
  so 
  far 
  as 
  we 
  have 
  been 
  able 
  to 
  carry 
  the 
  investigations, 
  

   the 
  processes 
  in 
  the 
  living 
  plant 
  and 
  in 
  the 
  laboratory 
  show 
  most 
  

   striking 
  resemblance, 
  not 
  only 
  in 
  the 
  compounds 
  which 
  are 
  formed, 
  

   but 
  in 
  every 
  feature 
  w^hich 
  is 
  characteristic 
  of 
  either 
  of 
  them. 
  

  

  For 
  my 
  own 
  part 
  I 
  would 
  go 
  further 
  than 
  this, 
  because 
  I 
  believe 
  

   that 
  these 
  experimental 
  results 
  help 
  us 
  to 
  gain 
  some 
  understanding 
  of 
  

   the 
  chemistry 
  of 
  life, 
  the 
  chemistry 
  which 
  is 
  so 
  different 
  from 
  that 
  of 
  

   man's 
  achievements 
  with 
  his 
  test 
  tube, 
  flask, 
  and 
  beaker. 
  Within 
  the 
  

   confines 
  of 
  vital 
  chemistry 
  reactions 
  take 
  place 
  which 
  are 
  so 
  far 
  

   outside 
  our 
  own 
  experimental 
  experience 
  that 
  it 
  came 
  to 
  be 
  believed 
  

   by 
  many 
  that 
  they 
  were 
  under 
  the 
  control 
  of 
  a 
  mysterious 
  force, 
  to 
  

   which 
  the 
  name 
  of 
  vis 
  vitalis 
  was 
  given. 
  One 
  of 
  these 
  processes 
  has 
  

   been 
  touched 
  upon 
  to-night, 
  the 
  condensation 
  of 
  the 
  simple 
  sugars, 
  

   glucose 
  and 
  fructose, 
  to 
  form 
  cane 
  sugar, 
  starch, 
  and 
  inulin. 
  No 
  one 
  

   has 
  yet 
  succeeded 
  in 
  effecting 
  these 
  syntheses 
  in 
  his 
  laboratory, 
  but 
  

   it 
  would 
  seem 
  that 
  something 
  of 
  that 
  nature 
  takes 
  place 
  in 
  our 
  

   photosynthesis. 
  Why 
  then 
  is 
  it 
  that 
  even 
  this 
  step 
  forward 
  has 
  

   been 
  gained? 
  

  

  The 
  one 
  lesson 
  that 
  we 
  have 
  gained 
  from 
  photosynthesis 
  is 
  that 
  

   the 
  definitive 
  factor 
  is 
  the 
  very 
  large 
  amount 
  of 
  energy 
  which 
  must 
  

   be 
  supplied 
  to 
  the 
  carbonic 
  acid 
  before 
  the 
  synthesis 
  of 
  the 
  simple 
  

   sugars 
  takes 
  place. 
  The 
  means 
  of 
  supplying 
  that 
  energy 
  do 
  not 
  

   concern 
  the 
  argument. 
  The 
  synthesis 
  proceeds 
  at 
  an 
  energy 
  level 
  

   which 
  is 
  far 
  higher 
  than 
  is 
  the 
  case 
  in 
  the 
  reactions 
  of 
  ordinary 
  

   chemistry, 
  and 
  the 
  sugars 
  are 
  formed 
  at 
  that 
  high 
  energy 
  level. 
  I 
  

   myself 
  believe 
  that 
  the 
  condensation 
  reactions 
  to 
  give 
  the 
  more 
  

   complex 
  carbohydrates 
  are 
  those 
  which 
  are 
  characteristic 
  of 
  the 
  

   simple 
  sugars 
  when 
  they 
  exist 
  at 
  the 
  high 
  energy 
  level. 
  The 
  reason 
  

   why 
  no 
  one 
  has 
  succeeded 
  up 
  till 
  now 
  in 
  inducing 
  these 
  reactions 
  

   to 
  take 
  place 
  is 
  because 
  no 
  one 
  has 
  hitherto 
  been 
  able 
  to 
  supply 
  the 
  

   large 
  energy 
  increment 
  necessary. 
  

  

  I 
  myself 
  believe 
  that 
  we 
  find 
  in 
  this 
  the 
  key 
  which 
  unlocks 
  the 
  

   door 
  of 
  vital 
  chemistry, 
  and 
  that 
  the 
  chemistry 
  of 
  all 
  life 
  is 
  one 
  

   of 
  high 
  energy, 
  our 
  laboratory 
  experience 
  being 
  confined 
  to 
  the 
  

   chemistry 
  of 
  low 
  energy. 
  From 
  this 
  viewpoint 
  I 
  see 
  a 
  wondrous 
  

   vista 
  unfold 
  itself, 
  wherein 
  new 
  understanding, 
  new 
  hopes, 
  and 
  new 
  

   possibilities 
  reveal 
  themselves. 
  Health 
  and 
  vitality 
  must 
  essentially 
  

   depend 
  on 
  the 
  high 
  energy 
  level 
  being 
  maintained; 
  any 
  lowering 
  of 
  

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