46 
would  be  very  small  and  the  work  would  be  slow  and  so  expensive, 
but  it  really  does  not  entail  so  much  labour  as  would  appear,  as 
the  cut  and  fixing  the  cup  done  by  two  men  experienced  in  th^ 
work  takes  a very  short  time. 
We  found  that  the  latex  here  coagulates  more  quickly  than  it 
does  in  the  Amazons,  probably  on  account  of  the  greater  heat  dur- 
ing our  late  experiments,  and  to  prevent  this  the  man  who  fixes  the 
cup  puts  a few  drops  of  water  in  the  bottom,  which  prevents  its 
coagulating  at  once.  The  addition  of  water  does  not  give  much 
trouble  in  recovering  the  rubber  even  if  by  accident,  as  during  a 
heavy  rain  storm,  the  cups  are  filled.  This  occurred  on  one  afternoon 
when  during  the  tapping  a violent  shower,  diluted  the  milk  to 
overflowing.  The  milk  was  strained  and  acidified  by  acetic  acid, 
and  though  the  water  was  in  excessive  proportion,  on  re-straining 
the  liquid,  it  was  found  quite  easy  to  recover  the  whole  of  the 
rubber. 
One  attempt  was  made  to  prepare  the  rubber  by  smoking  it  in 
the  Brazilian  method,  but  as  the  apparatus  was  not  satisfactory  the 
result  was  not  successful.  In  the  later  experiments  the  rubber 
was  coagulated  in  enamelled  plates  with  acetic  acid  as  described 
in  Mr.  ArdE.n’s  paper. 
After  M.  Bunnkchaux  left,  Mr.  Mach.ado  continued  experi- 
ments on  a hundred  trees  tapping  them  each  day,  using  sometimes 
the  little  axe,  at  others  a chisel  and  mallet.  The  former  is  un- 
doubtedly the  quicker  instrument,  but  is  apt  to  start  the  bark  on 
either  side  of  the  cut;  whether  this  will  prove  injurious  to  the  tree 
or  not  remains  to  be  seen.  At  the  same  time  the  axe  makes  a 
wound  of  the  same  size  and  shape  each  time  and  by  getting  an  axe 
made  of  suitable  size  and  with  a cutting  edge  of  the  right  form,  a 
coolie  can  make  fewer  blunders  in  cutting,  while  with  the  mallet 
and  chisel  he  is  very  apt  to  cut  out  too  large  a piece  of  bark,  and 
so  make  a wound  which  takes  longer  to  heal. 
It  was  observed  that  when  thi‘  tree  was  beaten  witli  the  mallet 
in  the  vicinity  of  the  cut  but  not  hard  enough  to  bruise  the  bark, 
the  flow  of  latex  appeared  distinctly  to  increase. 
On  March  qth,  Mr.  MachaijO  commenced  experimental  tapping 
on  lOO  trees  in  a triangular  plot  of  ground  near  the  entrance  of 
the  Economic  (iardens.  d'he  circumft'rence  of  all  the  trees  at  four  | 
feet  from  the  ground  was  281  feet  7 inches.  Average  circumfer- 
ence per  tree  2 feet  10  inches.  The  largest  tree  was  5 feet  i inch  ; 
in  circumference,  the  smallest  one  foot  3 inches,  ddie  oldest  trees 
here  are  about  15  years  old,  but  many  are  seedlings  of  later  date. 
At  least  25  were  under  two  feet  in  circumference  and  obviously 
young  plants  of  6 or  8 years,  ddie  trees  are  not  quite  ten  feet  apart. 
The  soil  is  damp  and  low-lying  and  occasionally  flooded. 
The  trees  were  tapped  at  6 o’clock  in  the  mornings  every  day 
e.xcept  Sunday,  and  one  other  day,  and  twice  when  the  tapping 
was  done  in  the  afternoon.  For  the  first  five  days  each  tree  re- 
ceived one  tap,  i.c.  a single  cut,  on  the  ne.xt  four  two  each,  and 
on  two  days  20  trees  received  ten  cuts  each.  In  the  table  append-  ' 
ed  it  will  be  noticed  that  it  took  two  days  to  call  the  latex,  only 
