EXTEMPORANEOUS  PHARMACEUTICAL  PREPARATIONS.  205 
to  consist  of  impurities  and  particles  of  the  resin  which  had 
escaped  solution  in  the  oil. 
Exp,  2d  One  drachm  of  resin  of  guaiac  was  triturated  with 
half  a  drachm  of  carbonate  of  soda  and  a  few  drops  of  water, 
until  of  a  uniform  pasty  consistence ;  it  was  then  made  into  an 
emulsion,  with  one  drachm  each  of  sugar  and  gum  arabic  and  a 
sufficient  quantity  of  water  to  measure  one  fluid-ounce.  A  slight 
deposit  only  occurred  with  this  mixture.  The  effect  of  the  soda 
on  the  taste  was  to  give  a  flavor  strongly  resembling  that  of 
cloves. 
ON  THE  BEST  METHOD  OF  SUSPENDING  BALSAM  OF  TOLU  IN 
AQUEOUS  MIXTURES. 
Exp.  Ist. — One  scruple  of  tolu  was  dissolved  in  ether,  and 
triturated  with  one  scruple  of  sugar  and  two  of  gum  arabic, 
until  all  the  ether  was  dissipated,  and  a  dry  powder  remained  ; 
this  was  mixed  with  half  a  fluid-ounce  of  water  gradually  added, 
and  formed  at  the  time  a  very  handsome  emulsion  ;  but  the  par- 
ticles of  the  balsam  slowly  agglutinated,  and  finally  formed  a 
mass  at  the  bottom  of  the  vessel. 
Exp.  2d. — One  scruple  of  balsam  of  tolu  was  dissolved  /in 
ether,  and  mixed  with  the  white  of  an  egg,  triturated  until  ail 
the  ether  was  dissipated,  and  then  mixed  with  a  small  quantity 
of  water.    The  tolu  subsequently  precipitated. 
Exp.  3c?. — One  drachm  of  very  hard,  pulverizable  tolu  was 
partially  dissolved  in  olive  oil,  in  a  heated  mortar  ;  this  was 
readily  made  into  an  emulsion  with  two  drachms  of  gum  arabic 
and  a  sufficient  quantity  of  water  to  make  the  whole  measure 
one  fluid  ounce. 
A  deposit  which  fell  seemed  to  consist  almost  entirely  of  im- 
purities, the  emulsion  continuing  very  dense  and  possessing  the 
taste  of  the  balsam  in  a  very  marked  degree. 
Exp.  ith, — An  attempt  to  form  a  more  perfect  solution  of 
the  tolu  in  olive  oil,  by  dissolving  the  balsam  in  ether,  mixing 
with  the  oil,  and  then  triturating  until  all  the  ether  was  dissipa- 
ted, was  not  successful,  the  tolu  concreting  into  a  mass  when 
deprived  of  ether. 
Exp.  5th. — One  drachm  of  balsam  of  tolu  was  triturated  with 
half  a  drachm  of  carbonate  of  soda  and  a  few  drops  of  water, 
until  of  a  smooth  consistence ;  it  was  then  made  into  an  emul- 
