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GUMS  AND  RESINS  OF  COMMERCE. 
Freemantle,  for  <£4  per  ton,  the  ton  weight  measuring  forty-five 
cubic  feet  when  pressed.  The  quantity  of  gas  obtained  by  Capt. 
Wray's  experiments,  was  at  least  four  cubic  feet  to  the  pound  o£ 
resin  and  leaves,  but  much  more  might  be  obtained  by  a  more 
complete  apparatus. 
A  cart  load  of  the  plants,  8  in  number,  weighed  1048  pounds. 
When  the  core  was  removed  the  leaves  and  resin  weighed  628 
pounds.  This  core  is  very  good  fuel  when  mixed  with  other 
wood.  The  specific  gravity  of  the  gas  is  888.  The  products  of 
the  distillation  are  gas,  tar,  and  coke.  The  tar  obtained  was 
about  1  quart  for  every  10  lbs.,  and  this,  when  re-distilled,  gave 
8  per  cent,  fluid  ounces  of  naptha,  and  20  per  cent,  of  a  sweet 
spirituous  non-inflammable  liquor.  The  coke  remaining  was 
about  I  of  the  original  weight,  and  with  other  fuel  burns  well. 
The  coke  of  the  leaf  has  a  bright  shining  appearance,  and  when 
ground  with  oil  is  a  very  good  substitute  for  lamp  black  in  paint. 
The  gas  has  a  smell  somewhat  similar  to  coal  gas,  not  nearly  so 
offensive,  but  sufficiently  strong  to  make  any  escape  immediately 
perceptible.  Its  illumimating  power  appears  to  be  very  superior 
to  coal  gas,  and  its  light  very  white. 
Captain  Wray  is  of  opinion  that  when  the  production  of  the 
gas  from  the  resin  of  the  Xanthorrhoea  is  conducted  with  suitable 
apparatus,  the  cost  per  annum  will  be  materially  reduced,  so  far 
indeed  that  the  resin  may  become  a  large  and  profitable  export 
from  the  colony  to  places  which  are  not  lit  at  all,  or  lit  with  oil. 
Among  these  may  be  enumerated  Singapore,  Hong  Kong,  Mel- 
bourne, and  Adelaide. 
The  supply  is,  I  may  say,  unlimited,  and  even  were  it  is  not 
so,  it  would  be  advantageous  to  get  rid  of  the  plant  from  all  the 
land  fit  for  cultivation.  Should,  however,  it  be  found  that  the 
plant  was  likely  to  get  scarce,  the  resin  might  be  obtained  by 
tapping. 
The  gum  resin  of  the  New  Zealand  flax  (Phormium  tenax)  is 
admirably  adapted  for  sealing  letters,  and  when  remittances  are 
enclosed,  is  frequently  made  use  of  by  the  colonists  for  that  pur- 
pose. It  is  insoluble  either  in  water  or  spirit,  and  so  thoroughly 
penetrates  the  envelope  as  to  become  part  and  parcel  of  it,  nor  is 
it  possible  to  get  at  the  contents  of  a  letter  so  sealed. 
One  of  the  gum  trees  of  Popayan  in  Colombia  yields  a  resin  so 
