Am.  Jour.  Pharm.\ 
April,  1890.  j 
Cod  Liver  Oil  Emulsion. 
183 
Of  all  the  excipients  suggested  by  different  authorities  as  well  as 
commending  themselves  to  one's  own  approval  for  emulsifying  cod 
liver  oil,  none,  I  think,  equals  gum  tragacanth.  Without,  therefore, 
ignoring  other  substances,  such  as  mucilage  of  gum  arabic,  white  of 
egg,  alkaline  solutions,  and  so  on,  I  have  principally  endeavored 
to  ascertain  the  conditions  most  favorable  to  produce  with  traga- 
canth an  inseparable  emulsion,  which,  at  the  same  time,  would  be 
miscible  with  water,  contain  a  reasonable  amount  of  oil,  and  be  not 
particularly  objectionable  in  appearance,  taste  or  smell.  Of  course, 
in  all  these  preparations,  much  may  be  left  to  individual  fancy  as  to 
combination ;  and  I,  therefore,  make  no  suggestion  as  to  all  the  dif- 
ferent ingredients  which  may  be  added,  further  than  this,  that  if  oil 
of  bitter  almond  be  the  flavoring  agent  used,  both  experience  and 
experiment  have  determined  that  a  half  per  cent.,  or  about  two 
drops  to  each  ounce  of  cod  liver  oil,  is  the  proper  proportion  ;  and 
that  of  the  two  oils,  namely,  an  oil  deprived  of  its  hydrocyanic  acid, 
or  an  oil  containing  it,  the  latter  is  preferable. 
As  to  the  emulsion,  let  three  drachms  of  the  finest  white  pow- 
dered tragacanth  be  rubbed  up  in  a  large  mortar  with  three  ounces 
of  glycerin,  to  this  add  as  much  boiling  water  as  will  convert  it  into 
a  thick,  transparent  jelly,  from  eight  to  ten  ounces  probably  being 
required.  After  cooling  add  the  cod  liver  oil,  which  should  first  be 
mixed  either  with  plain  water  or  lime-water,  in  the  proportion  o  f 
one  of  the  latter  to  three  of  the  oil ;  or,  if  the  emulsion  is  intended 
to  contain  the  hypophosphites  of  lime  or  soda,  let  these  be  added  to 
the  plain  water  previous  to  mixing  with  the  oil,  and  then  let  this 
primary  emulsion  be  gradually  added  to  the  mucilage  of  tragacanth 
with  constant  stirring.  In  the  process  of  mixing,  the  emulsion  not 
only  creams  but  also  thickens  up  to  a  certain  point ;  the  individual 
taste  must  settle  the  extent  to  which  the  mixture  may  be  carried. 
I  have  found  the  three  drachms  of  tragacanth  emulsify  from  fifty  to 
eighty  ounces  of  what  I  have  called  the  primary  emulsion,  the 
former  quantity  being  very  thick  and  not  easily  poured  from  the 
mortar,  the  latter  quantity  flowing  more  freely  and  forming  what  I 
consider  the  better  emulsion.  In  mixing  the  oil  with  the  mucilage 
of  tragacanth,  care  must  be  taken  not  to  add  it  too  hurriedly,  else  it 
will  not  emulsify ;  the  mixture  will  simply  break  up  into  a  clotted 
mass,  and  no  amount  of  labor,  apparently,  will  bring  it  back  to  the 
emulsified  form.    Under  these  circumstances,  the  better  way  is  at 
