Am,  Jour  Pharm,  \ 
April,  1882.  j 
Emulsions. 
181 
that  a  certain  amount  of  knowledge  and  skill  are  required,  that 
machinery  is  a  necessity  to  the  production  of  emulsions  in  largfe  quan- 
tities, and  that  capital  and  a  good  market  are  advantageous  in  a  com- 
mercial sense,  their  production  requires  no  more  knowledge  and  not 
as  much  skill  as  does  the  compounding  of  most  of  the  prescriptions 
daily  put  up  in  our  pharmacies,  while  all  the  apparatus  necessary  are 
a  mortar  and  pestle  and  accurate  implements  of  measurement.  These, 
•with  good,  fresh  codliver  oil — which  ean  be  obtained  without  diffi- 
culty— make  the  ]:>roduction  of  an  emulsion  as  easy  an  operation  as 
the  compounding  of  the  simplest  prescription.  Moreover,  such  emul- 
sions jDOSsess  real  advantages  over  the  manufactured  article.  They  are, 
in  the  first  place,  perfect  emulsions,  which  the  commercial  products  in 
many  cases  are  not.  Then  being  ])repared  at  the  time  when  they  are 
prescribed,  they  are  al)Solutely  fresh  ;  and  there  is  perhaps  no  class  of 
preparations  in  which  this  is  more  desirable.  It  is  true  the  manufac- 
turers usually  claim  that  their  emulsions  keep  well ;  but  at  the  same 
time  they  are  very  careful  to  recommend  that  such  be  kept  in  a  cool 
place.  The  truth  is  that  notwithstanding  such  care  the  preparations 
furnished  soon  undergo  change,  become  unsightly  and  unfit  for  use ; 
and  if  it  is  further  considered  that  this  care  in  their  preservation  can- 
not always  be  observed,  and,  as  a  rule,  is  disregarded  both  by  the 
wholesaler  and  retailer,  it  cannot  be  wondered  that  manufactured 
■emulsions  are  often  dispensed  in  a  very  unfatisfactory  condition. 
These  considerations  have  suggested  to  me  the  ])ropriety  of  olfering 
some  formulas  for  emulsions,  in  the  hope  that  in  the  absence  of  author- 
itative formulas  physicians  may  find  them  of  sufficient  merit  to  adopt 
them  in  their  practice;  giving  them  at  the  same  time  the  assurance 
that  careful  pharmacists  following  them  will  succeed  as  well  as  I  have 
succeeded  in  preparing  them. 
The  successful  formation  of  emulsions,  whether  of  fixed  or  volatile 
oils,  is  dependent  upon  certain  rules,  well  understood  by  accomplished 
pharmacists,  which  when  deviated  from  will  invariably  embarrass  the 
operator,  either  by  retarding  or  completely  preventing  perfect  emulsifi- 
cation.    These  rules  are  : 
1.  That  the  water  and  gum  arable'  shall  be  in  definite  and  absolute 
^  The  writer  is  well  aware  that  other  emulsifying  agents  have  been  i^ro- 
posed  and  are  used,  but  he  is  satisfied  that  none  of  these  answer  as  well  as 
does  gum  arable. 
