21 
Formol ! the  very  coagulant  preconised  by  Dr.  C.  O.  Weber. 
When  Doctors  disagree  &c.  &c.  I do  not  say  this  in  disparage- 
ment of  Dr.  Webers’  statement;  he  is  far  too  great  an  authority 
for  me  to  dispute  his  statements,  but  his  method  has  against  it  that 
it  is  open  to  the  same  objection  as  other  chemical  coagulations  viz : 
that  we  do  not  yet  know  the  behaviour  of  the  product  in  its  ulti- 
mate manufactured  state. 
The  fact  is,  the  very  nature  of  india-rubber  in  its  pure  state  is 
so  litttle  known,  the  particular  physical  arrangement  of  molecules 
which  gives  it  its  tensility  and  the  property  of  re-traction  is  so  little 
understood  : we  have  such  dim  notions  of  the  way  in  which  the 
various  elements  of  the  latex,  which  goto  form  the  constituents  of 
pure  rubber,  combine  or  separate  in  the  act  of  coagulation,  that  we 
must  be  content,  in  the  present  state  of  our  knowledge,  yet  awhile 
to  tread  the  old  beaten  tracks  of  empirism. 
Take  for  instance,  centrifugalisation  of  the  latex.  In  aiming  at 
producing  a pure  crude  rubber,  we  strive;  after  all  foreign  impurities 
have  been  eliminated,  to  work  out  the  destruction  of  the  fermen- 
tescent  elements  or  proteids ; well ! centrifugising  does  it,  and 
what  is  the  result‘d — a rubber  which  in  the  vulcanizing  process  loses 
its  tenacity  and  vitality — a product  inferior  to  that  of  coagulation 
by  heat ! 
I will  not  linger  on  the  “centrifugal’’  process.  To  obtain  7,000 
revolutions  a minute — the  speed  required  in  the  treatment  of 
Hevea — a motor  will  be  required — that  disposes  of  the  matter  for 
the  present  at  any  rate. 
To  resume  this  already  too  long  letter,  my  invention  is  simply  a 
mechanical  and  automatic  adaptation  of  the  Brazilian  method. 
That  method  has  stood  the  test  of  time ; it  has  answered  all  the 
requirements  of  manufacturers.  It  stands  on  proved  merits,  which 
cannot  be  said  unreservedly,  so  far,  of  any  other  method  of  pre- 
paring rubber. 
The  apparatus  itself  is  extremely  simple;  one  coolie  can  work  it 
without  effort ; it  is  light ; it  requires  no  special  installation  and 
can  be  transported  to  the  fields,  if  need  be. 
E.  MATH  I ELI. 
Singapore , 28th  January , 
PARA  RUBBER  TREES  AT  HIGH  ELEVATIONS. 
In  reply  to  an  enquiry,  whether  Para  rubber  would  be  profitable 
if  grown  at  an  elevation  of  1,600  feet  to  1,800  feet,  Mr.  F.  J.  Hoi>- 
LOWAY  of  Kepitigulla,  Matale,  Ceylon,  writes  to  the  Times  of 
Ceylon: — I am  now  tapping  some  trees  at  about  1,600  feet,  on  a 
hillside,  and  am  very  pleased  with  the  excellent  results  obtained. 
Frees  at  this  elevation,  although  a good  deal  smaller  than  the  ones 
of  the  same  age  at  a lower  elevation,  are  now  being  proved  to 
yield  better  than  those  lower  down. 
They  only  require  one  incision  in  the  morning,  and  the  cups  are 
emptied  at  1 1 a.  m.  and  replaced  under  the  same  cut  immediately,  , 
