uT/zs^t""^'}  Tincture  of  ^iilaia  as  an  Emulsifying  Agent.  41 
have  had  cigarettes  made  with  stramonium  and  lobelia  only  ;  so  that 
altogether  I  have  three  different  kinds  for  use  :  opium  cigarettes,  con- 
taining a  small  quantity  of  opium  and  stramonium  ;  a  compound  opiated 
cigarette,  containing  the  drugs  given  in  the  formula  above,  and  a  stra- 
monium cigarette  without  opium. — Pharm.  four.^  Nov.  15,  1879. 
TINCTURE  of  QUILLAIA  as  an  EMULSIFYING  AGENT. 
Henry  Collier,  Teacher  of  Pharmacy  at  Guy's  Hospital. 
Read  before  the  British  Pharmaceutical  Conference. 
I  now  pass  on  to  a  consideration  of  the  use  of  a  tincture  of  the  bark 
of  Quillaia  saponaria  for  the  preparation  of  emulsions.  The  tincture 
which  has  been  employed  in  the  preparation  of  the  various  mixtures 
upon  the  table  has  been  made  according  to  the  following  formula,  which 
is  taken  from  Guy's  Hospital  Pharmacopoeia: 
Quillaia  bark,  in  coarse  powder,  .  .  .  4  oz. 
Rectified  spirit  of  wine,  .  .  .1  pint. 
Digest  for  three  days,  and  then  strain. 
The  bark  before  powdering  is  carefully  freed  from  all  remains  of 
outside  layer,  and  the  tincture  produced  is  of  a  pale  yellow  color. 
Into  this  bottle  I  have  put  some  meicury,  and  shaken  it  up  with  tinc- 
ture of  quillaia.  The  result  is  that  the  mercury  has  been  reduced  to  a 
very  fine  state  of  division.  It  has  very  much  the  appearance  of  hyd.  c. 
creta,  and  examined  with  a  lens  it  is  seen  to  be  composed  of  distinct 
globules  of  mercury.  So  long  as  there  is  some  tincture  present  this 
■division  of  the  metal  remains  j  if  it  be  dried,  it  at  once  runs  together 
and  appears  in  its  ordinary  liquid  state.  This  is  a  remarkable  power 
which  tinct.  quillalae  possesses  of  destroying  the  cohesion  between  the 
globules  of  mercury,  breaking  them  up  and  preventing  them  from  unit- 
ing together;  and  it  is  this  property  which  renders  it  so  valuable  an 
emulsifying  agent. 
A  true  emulsion  consists,  as  is  well  known,  of  a  number  of  oily  or 
resinous  particles  floating  about  in  a  watery  liquid  by  means  of  some 
agent  which  prevents  them  from  cohering.  To  be  perfect,  the  emul- 
sion should  have  a  milky  appearance,  and  the  suspended  particles  should 
not  subside  or  rise  too  rapidly.  In  the  British  Pharmacopoeia  there  is 
a  preparation  containing  mercury  In  a  very  fine  state  of  division,  and 
which  is,  in  fact,  an  emulsion  containing  mercury  finely  divided.  The 
