﻿NATURAL 
  RUBBER 
  — 
  COOK 
  401 
  

  

  Nobody 
  could 
  know 
  beforehand 
  how 
  soon 
  the 
  Para 
  rubber 
  of 
  the 
  

   East 
  Indian 
  plantations 
  would 
  come, 
  like 
  the 
  cotton 
  of 
  our 
  Southern 
  

   States, 
  into 
  speculative 
  markets 
  where 
  prices 
  would 
  be 
  forced 
  down 
  far 
  

   below 
  the 
  costs 
  of 
  production 
  by 
  a 
  normal 
  farming 
  population, 
  to 
  12 
  

   cents, 
  10 
  cents, 
  or 
  5 
  cents. 
  The 
  rapid 
  advance 
  to 
  large-scale 
  pro- 
  

   duction 
  of 
  rubber 
  in 
  Malaya 
  had 
  the 
  effect 
  in 
  a 
  few 
  years 
  of 
  pre- 
  

   empting 
  the 
  field 
  and 
  placing 
  commercial 
  handicaps 
  on 
  any 
  alterna- 
  

   tive 
  developments. 
  Every 
  invention 
  or 
  improvement 
  runs 
  the 
  risk 
  

   of 
  being 
  blanketed 
  or 
  outrun 
  by 
  some 
  competing 
  improvement, 
  more 
  

   effective 
  or 
  more 
  attractive. 
  The 
  chance 
  of 
  such 
  a 
  discovery 
  and 
  de- 
  

   velopment 
  as 
  took 
  place 
  with 
  the 
  Para 
  rubber 
  in 
  the 
  East 
  Indies 
  must 
  

   be 
  considered 
  very 
  small, 
  but 
  it 
  did 
  actually 
  occur, 
  with 
  the 
  effect 
  of 
  

   reducing 
  the 
  Castilla 
  and 
  guayule 
  projects 
  to 
  the 
  status 
  of 
  nearly 
  

   complete 
  failures, 
  as 
  long 
  as 
  rubber 
  could 
  be 
  had 
  in 
  unlimited 
  quan- 
  

   tities 
  from 
  the 
  East 
  Indies. 
  

  

  POSSIBILITY 
  OF 
  APPLYING 
  GUAYULE 
  EXTRACTION 
  METHODS 
  TO 
  CASTILLA 
  

  

  A 
  possibility 
  recognized 
  in 
  recent 
  years 
  is 
  that 
  the 
  mechanical 
  

   methods 
  of 
  extraction 
  developed 
  through 
  the 
  long 
  experience 
  with 
  

   guayule 
  may 
  be 
  adapted 
  to 
  the 
  extraction 
  of 
  rubber 
  from 
  the 
  bark 
  of 
  

   the 
  Castilla 
  tree. 
  An 
  observation 
  was 
  made 
  in 
  Haiti 
  in 
  1930, 
  reported 
  

   in 
  1937 
  and 
  in 
  1943, 
  of 
  the 
  finding 
  of 
  good-quality 
  rubber 
  in 
  decaying 
  

   Castilla 
  bark, 
  instead 
  of 
  merely 
  a 
  black 
  pasty 
  residue 
  left 
  by 
  the 
  latex 
  

   in 
  the 
  dead 
  bark, 
  as 
  previously 
  observed 
  and 
  ascribed 
  to 
  the 
  action 
  

   of 
  the 
  oxidizing 
  enzyme. 
  This 
  internal 
  coagulation 
  of 
  the 
  latex 
  means 
  

   that 
  the 
  rubber 
  of 
  Castilla 
  is 
  brought 
  within 
  the 
  possibility 
  of 
  

   mechanical 
  extraction 
  by 
  grinding 
  the 
  bark 
  and 
  separating 
  the 
  rub- 
  

   ber, 
  as 
  practiced 
  with 
  guayule. 
  Such 
  an 
  approach 
  to 
  mechanical 
  ex- 
  

   traction 
  is 
  entirely 
  different 
  from 
  attempting 
  to 
  draw 
  out 
  or 
  to 
  squeeze 
  

   out 
  the 
  latex, 
  or 
  to 
  extract 
  the 
  rubber 
  by 
  solvents. 
  The 
  means 
  of 
  

   coagulating 
  the 
  rubber 
  in 
  the 
  Castilla 
  latex 
  is 
  a 
  simple 
  heat 
  treatment 
  

   to 
  destroy 
  the 
  oxidizing 
  enzyme, 
  only 
  moderate 
  temperatures 
  below 
  

   the 
  boiling 
  point 
  being 
  required. 
  

  

  Mechanical 
  extraction 
  of 
  Castilla 
  rubber, 
  if 
  a 
  feasible 
  process 
  were 
  

   worked 
  out, 
  would 
  open 
  the 
  way 
  to 
  a 
  system 
  of 
  rubber 
  production 
  

   requiring 
  much 
  less 
  labor 
  than 
  for 
  tapping 
  and 
  collecting 
  the 
  latex 
  

   in 
  plantations 
  of 
  the 
  Para 
  rubber 
  tree. 
  The 
  reason 
  why 
  a 
  mechanical 
  

   system 
  is 
  less 
  applicable 
  to 
  the 
  Para 
  rubber 
  tree 
  is 
  that 
  the 
  latex 
  layer 
  

   of 
  the 
  bark 
  is 
  only 
  a 
  few 
  millimeters 
  thick, 
  while 
  that 
  of 
  Castilla 
  

   attains 
  a 
  centimeter 
  or 
  more 
  in 
  thickness. 
  Only 
  a 
  small 
  proportion 
  

   of 
  the 
  rubber 
  material 
  in 
  the 
  latex 
  tubes 
  of 
  Castilla 
  trees 
  has 
  been 
  

   extracted 
  by 
  any 
  of 
  the 
  methods 
  of 
  tapping 
  used 
  in 
  the 
  past. 
  

  

  A 
  popular 
  impression 
  that 
  the 
  latex 
  of 
  Castilla 
  "pours 
  like 
  water 
  

   from 
  a 
  pipe," 
  and 
  that 
  "the 
  entire 
  content 
  of 
  rubber 
  runs 
  out 
  quickly," 
  

  

  