418  New  Zealand  Kauri  Gum.  { ^°'Ai?r  ^sr""* 
cent.,  and  that  in  no  case  can  it  be  used  in  solutions  as  dilute  as  1  part 
in  250. 
Secondly — That  the  color  is  not  due  to  aloin,  and  if  due  to  a  tannin- 
like substance  it  must  be  a  variety  which  is  soluble  in  benzin. 
Thirdly — That  extreme  care  must  be  taken  when  employing  this 
test  for  the  detection  of  aloes,  that  the  benzin  layer  is  perfectly  clear 
before  decanting  from  the  underlying  liquor. 
The  foregoing  experiments  were  carried  out  in  the  laboratories  of 
the  Society's  School  of  Pharmacy. — Phar.  Jour,  and  Trans.,  June  18, 
1881. 
ON  NEW  ZEALAND  KAURI  GUM. 
By  Edwakb  H.  Rennie,  M.A.  (Sydney),  B.Sc.  (Loud.) 
This  resin,  which  is  the  product  of  a  coniferous  tree  {Dammara 
australis)  growing  in  New  Zealand,  seems  to  have  been  first  examined 
in  1843,  by  R.  D.  Thomson  (^'Ann.  Cliim.  Phys.''  [3],  9,  p.  499), 
who  obtained  from  it,  by  distillation  at  a  gentle  heat,  an  amber- 
colored  oil  containing  82*2  per  cent,  carbon  and  IIT  per  cent,  hydro- 
gen, to  which  he  gave  the  name  Dammarol. 
It  was  again  examined  in  1874  by  M.  M.  P.  Muir  (this  Journal, 
1874,  p.  472),  who  obtained  from  it,  by  dry  distillation,  an  oil 
boiling  between  155°  and  156°,  which  contained  79*07  per  cent,  car- 
bon and  10*90  per  cent,  hydrogen,  to  which  he  ascribed  ])rovisionally 
the  formula  C10H20O7,  stating,  howe\'er,  that  the  quantity  at  his  dis- 
2)osal  was  too  small  to  make  certain  of  the  purity  of  his  product. 
Having  a  considerable  quantity  of  the  Kauri  gum  at  my  disposal,  I 
have  thought  it  worth  Avhile  to  re-examine  it,  especially  with  regard 
to  the  volatile  oil  above  mentioned. 
The  resin  exhibited  physical  properties  very  similar  to  those 
described  by  previous  observers.  It  was  thought  better,  instead  of 
subjecting  it  to  dry  distillation,  to  place  it  in  a  copper  vessel  which 
was  heated  by  a  gas  flame,  and  through  which  a  rapid  current  of  steam 
was  kept  passing.  The  distillation  was  continued  until  a  semi-solid 
sticky  product  began  to  form  in  the  condenser.  In  this  way  15  lbs. 
of  the  resin  yielded  about  750  cc.  of  oil.  The  latter,  having  been  sep- 
arated from  the  water,  was  fractionally  distilled.  A  very  small 
quantity  came  over  below  156°,  the  greater  part  coming  over  between 
this  temperature  and  160°.    A  small  quantity  came  over  between 
