20 
The  native  does  not  attempt  to  deal  with  a mass  of  milk  at  one 
time  ; he  dips  his  spatula  in  the  milk  and  presents  only  a very  thin 
coating  to  the  smoke  ; that  first  layer  having  solidified,  the  opera- 
tion is  repeated ; the  final  result  is  a series  of  thin  layers,  over- 
lapping one  another,  each  of  which  has  been  penetrated  through 
and  through  by  the  heat,  and  antiseptised  by  it. 
But,  with  all  its  effectiveness,  the  Brazilian  method  is  slow  and 
tedious ; it  requires  an  amount  of  sustained  attention  of  which  the 
native  is  not  often  capable  ; sometimes  a portion  of  the  rubber  will 
be  burned  ; another  portion,  insufficiently  smoked,  will  readily  de- 
compose. Moreover,  it  is  quite  unsuited  to  meet  the  requirements 
of  an  estate  of  some  size. 
My  invention  is  a mechanical  adaptation  of  the  Brazilian  process, 
so  contrived  that,  the  work  is  performed  automatically  or  nearly  so. 
The  flow  of  the  filtered  latex  can  be  regulated  at  the  start  of  the 
operation,  to  the  thinness  of  a mere  film  and  the  substance  runs  in 
an  uninterrupted  sheet  on  to  a heated  surface  kept  at  a uniform 
and  constant  temperature  throughout.  The  flow  of  the  latex  re- 
mains even  until  the  whole  milk  is  worked  off.  I have  simply  aimed 
at  reproducing  exactly  the  conditions  under  which  the  Brazilian 
method  is  conducted,  while  at  the  same  time  regulating  it  and  free- 
ing it  from  the  defects  inherent  to  the  listlessness  of  the  native 
operator.  It  is  not  contended  that  the  process  does  away  with  the 
proteids  any  more  than  chemical  coagulation  does ; but  there  is 
more  in  the  action  of  heat  thus  employed,  than  the  mere  evapora- 
tion of  the  water  of  the  latex.  Presented  in  the  shape  of  a thin 
film,  the  latex  is  seized  and  penetrated  through  and  through  by  the 
heat,  the  result  being  a kind  of  “ pasteurisation’’  of  the  thin  mass, 
which  robs  the  proteids,  now  solidified  and  insoluble,  of  their  septic 
properties.  Hence  the  freedom  of  well  cured  and  dried  para-rubber 
from  decomposition. 
This  brings  me  to  the  process  preconised  by  Dr.  C.  O.  VVebrr 
of  coagulation  by  formaldehyde.  Formaldehyde  or  formol,  sold 
in  the  trade  under  the  name  of  formaline  as  a 40%  solution  is  known 
to  form  compounds  with  albuminous  substances  often  rendering 
them  insoluble;  and,  being  at  the  same  time  a most  powerful  anti- 
septic it  would  appear  to  be  a complete  coagulant.  And  yet,  even 
in  this  case,  the  removal  of  the  proteids  does  not  seem  to  be  com- 
pletely accomplished,  for  we  see  that,  after  the  coagulation  has 
been  effected,  it  is  recommended,  “ in  order  to  remove  all  traces  of 
“ albumen  that  may  be  suspended,  to  cut  the  rubber  into  strips  and 
“ subject  it  to  a thorough  washing  upon  an  ordinary  rubber  wash- 
“ ing  machine.  ” 
Perhaps,  then,  the  last  word  of  “ proteid-free  ” coagulation  is 
not  yet  found  ? 
Strange  to  say,  Mr.  Ha.MICT  who  experimented  with  every  con- 
ceivable re-agent,  gives  fluoride  of  sodium  as  the  complete  coagu- 
lant to-tally  destroying  proteids;  and  after  enumerating  the  other 
coagulants  which  he  employed  with  more,  or  less  success,  he  winds 
up  by  saying;  other  antiseptics,  salol,  gaiiol,  formol  etc.  do  not 
“ coagulate. 
