﻿212 
  

  

  Prof. 
  B. 
  Moore 
  and 
  Mr. 
  T. 
  A. 
  Webster. 
  

  

  nitrogen, 
  and 
  this 
  has 
  greatly 
  repressed 
  the 
  production 
  of 
  growth. 
  The 
  two 
  

   amounts 
  of 
  nitrogen 
  of 
  1*0 
  and 
  l'l 
  mgrm. 
  are, 
  however, 
  considerably 
  above 
  

   the 
  controls, 
  namely, 
  0*1 
  to 
  0*3, 
  so 
  that 
  it 
  would 
  appear 
  probable 
  that 
  there 
  

   was 
  a 
  slow 
  fixation 
  of 
  atmospheric 
  elemental 
  nitrogen. 
  (See 
  in 
  this 
  con 
  

   nection 
  the 
  next 
  experiment, 
  Nos. 
  3 
  and 
  4, 
  and 
  the 
  succeeding 
  paper 
  on 
  

   Marine 
  Algee.) 
  

  

  Experiment 
  3. 
  — 
  Commenced 
  August 
  9, 
  1918 
  ; 
  terminated 
  August 
  29, 
  1918. 
  

   This 
  set 
  was 
  likewise 
  carried 
  out 
  in 
  Kilner 
  jars, 
  and 
  was 
  designed 
  to 
  test 
  

   whether, 
  with 
  exclusion 
  of 
  the 
  free 
  atmosphere, 
  nutrition 
  and 
  growth 
  could 
  

   be 
  achieved 
  by 
  feeding 
  with 
  high 
  dilutions 
  of 
  carbon 
  dioxide, 
  and 
  of 
  oxides 
  

   of 
  nitrogen. 
  The 
  experiment 
  was 
  carried 
  out 
  as 
  follows 
  : 
  — 
  

  

  Eight 
  Kilner 
  jars 
  were 
  taken. 
  Each 
  of 
  these 
  received 
  100 
  c.c. 
  tap-water, 
  

   1 
  c.c. 
  of 
  a 
  1 
  per 
  cent, 
  solution 
  of 
  sodium 
  chloride, 
  1 
  c.c. 
  of 
  a 
  1 
  per 
  cent, 
  

   solution 
  of 
  alkaline 
  potassium 
  phosphate 
  (K2HPO4), 
  and 
  two 
  drops 
  of 
  a 
  

   1 
  per 
  cent, 
  solution 
  of 
  ferric 
  chloride 
  (equivalent 
  to 
  0'14 
  c.c). 
  Then 
  to 
  each 
  

   was 
  given 
  a 
  minute 
  insemination 
  of 
  1 
  c.c. 
  of 
  a 
  dilute 
  suspension 
  of 
  a 
  

   unicellular 
  green 
  algal 
  growth. 
  The 
  eight 
  jars 
  were 
  set 
  out 
  on 
  the 
  lawn 
  in 
  

   the 
  daylight 
  on 
  August 
  9, 
  each 
  being 
  loosely 
  covered 
  by 
  its 
  lid, 
  but 
  opened 
  

   daily, 
  so 
  as 
  to 
  establish 
  growth 
  in 
  each 
  case 
  preparatory 
  to 
  the 
  subsequent 
  

   treatment. 
  On 
  August 
  16 
  growths 
  are 
  evident, 
  and 
  about 
  equally 
  advanced 
  

   in 
  all 
  the 
  jars 
  ; 
  numerous 
  fresh 
  colonies 
  have 
  started 
  attached 
  to 
  the 
  

   bottoms, 
  and 
  in 
  the 
  precipitated 
  calcium 
  phosphate. 
  The 
  eight 
  jars 
  were 
  

   now 
  divided 
  into 
  four 
  pairs. 
  The 
  first 
  pair 
  (Nos. 
  1 
  and 
  2) 
  simply 
  had 
  their 
  

   lids 
  screwed 
  on 
  airtight. 
  The 
  second 
  pair 
  (Nos. 
  3 
  and 
  4) 
  first 
  had 
  a 
  narrow 
  

   test-tube, 
  similar 
  to 
  that 
  described 
  in 
  Experiment 
  2, 
  and 
  half 
  filled 
  with 
  

   solid 
  sodium 
  bicarbonate 
  inserted, 
  and 
  both 
  then 
  had 
  their 
  lids 
  screwed 
  on 
  

   airtight. 
  The 
  third 
  pair 
  (Nos. 
  5 
  and 
  6), 
  instead 
  of 
  the 
  sodium 
  bicarbonate 
  

   tube, 
  had 
  a 
  similar 
  tube, 
  containing 
  a 
  system 
  designed 
  to 
  evolve 
  nitrogen 
  

   peroxide 
  and 
  other 
  oxides 
  of 
  nitrogen 
  very 
  slowly 
  into 
  the 
  air 
  of 
  the 
  jar. 
  

   The 
  fourth 
  pair 
  (Nos. 
  7 
  and 
  8) 
  each 
  had 
  two 
  tubes, 
  one 
  containing 
  sodium 
  

   bicarbonate, 
  and 
  the 
  other 
  the 
  nitrous 
  system. 
  This 
  nitrous 
  system 
  was 
  

   constructed 
  thus 
  : 
  — 
  A 
  few 
  crystals 
  of 
  sodium 
  nitrite 
  were 
  introduced 
  into 
  

   the 
  narrow 
  test-tube, 
  the 
  tube 
  was 
  then 
  gently 
  half 
  filled 
  with 
  water, 
  and 
  on 
  

   top 
  of 
  this 
  there 
  was 
  introduced 
  a 
  column 
  of 
  about 
  3 
  cm. 
  of 
  1 
  in 
  10 
  nitric 
  

   acid. 
  

  

  The 
  design 
  of 
  the 
  experiment 
  was 
  to 
  shut 
  off 
  all 
  atmospheric 
  supply 
  of 
  

   carbon 
  dioxide 
  and 
  of 
  nitrites, 
  and 
  in 
  one 
  pair 
  leave 
  the 
  algse 
  destitute 
  of 
  

   both 
  these 
  ; 
  in 
  the 
  next, 
  supply 
  carbon 
  dioxide 
  and 
  restrict 
  nitrites 
  ; 
  in 
  the 
  

   third, 
  supply 
  nitrites 
  but 
  restrict 
  carbon 
  dioxide 
  ; 
  and, 
  in 
  the 
  fourth, 
  supply 
  

   both 
  carbon 
  dioxide 
  and 
  nitrites. 
  The 
  dissociation 
  pressure 
  of 
  carbon 
  

  

  