8oo 
Abstracts  from  Theses. 
(  Am.  Jour.  Pharm. 
(   November,  1920. 
ABSTRACTS  FROM  THESES.* 
Presented  by  Students  of  the  PniivADEiyPHiA  CoIvIvEge  of  Pharmacy  and 
Science. 
EMULSIONS  OF  BKNZYL  BENZOATS. 
The  extensive  use  of  Benzyl  Benzoate  and  its  disagreeable  taste 
has  given  the  pharmacist  an  opportunity  to  prepare  palatable  forms 
for  use  by  physicians. 
Edwin  T.  Brown,  in  his  Thesis  prepared  in  the  Pharmacy  Labora- 
tory, has  shown  that  an  emulsion  is  readily  prepared  by  the  use  of  the 
commonly  employed  emulsifying  agents  such  as  acacia  and  traga- 
canth,  but  that  the  best  results  followed  the  use  of  tragacanth,  2 
Gm.  per  100  Cc,  in  a  20  per  cent,  emulsion  of  benzyl  benzoate. 
He  also  tried  many  flavors,  including  varying  proportions  of 
aromatic  elixir  of  eriodictyon,  "aromol,"  10  and  20  drops  per  100 
Cc. ;  methyl  salicylate  and  oil  of  cinnamon,  each  12  drops  per  100 
Cc;  oil  of  cinnamon,  12  drops,  methyl  salicylate  18  drops  per  100 
Cc.  of  emulsion;  methyl  salicylate,  10  drops,  oil  of  sassafras,  8 
drops,  and  oil  of  sweet  orange  12  drops  per  100  mils;  12  drops  each 
of  the  same  three  oils  and  8  grains  of  vanillin  per  100  Cc.  of  emulsion. 
The  conclusion  reached  by  Mr.  Brown  is  that  20  drops  of 
"aromol"  or  12  drops  each  of  methyl  salicylate,  oil  of  sassafras  and 
sweet  orange  are  the  best  flavors  tried,  although  even  these  large 
amounts  of  aromatics  fail  to  completely  cover  the  disagreeable 
taste  of  the  benzyl  benzoate. 
NOTES  ON  THE  ASSAY  OF  PHOSPHORIC  ACID. 
The  U.  S.  p.  IX  assay  for  phosphoric  acid  has  proven  unsatis- 
factory in  the  hands  of  many  chemists.  This  assay  is  inconsistent 
in  its  conclusions,  and  therefore  inaccurate  because  of  the  varying 
amounts  of  zinc  oxide,  which  may  be  added,  and  which  make  up  a 
part  of  the  final  volume  from  which  an  aliquot  portion  is  taken  for 
titration. 
Mr.  H.  L.  Cline  in  a  thesis  prepared  in  the  Chemical  Laboratory 
proposes  to  overcome  this  difficulty  by  filtering  the  liquid,  after 
neutralization  with  zinc  oxide  (using  a  Gooch  crucible)  washing  the 
precipitate  with  water  until  free  from  silver  nitrate  and  adding 
distilled  water  to  make  the  total  volume  measure  exactly  100  mils. 
An  aliquot  portion  of  this  solution  is  then  titrated  with  tenth-normal 
*  Prepared  by  K.  Fullerton  Cook.  Ph.M.  and  A.  B.  Nichols,  Phar.D. 
