560 
Emulsions, 
Am.  Jour.  Pharm. 
Nov.,  1880. 
regard  the  intercellular  substance  of  this  bast  fibre  as  a  ^'  cellulide,"  or 
more  specifically  a  celluloquinone.  Upon  this  constituent  depends  the 
integrity  and  remarkable  dyeing  capacity  of  the  fibre  :  pari  passu  with 
its  removal  these  disappear  until  in  the  isolated  cellulose  there  is 
obtained  a  mass  of  disintegrated  cells,  having  no  afl&nity  for  coloring 
matters. 
By  the  action  of  nitric  acid  (5  per  cent.)  this  celluloquinone  is 
entirely  converted  into  soluble  products.  The  aromatic  portion  of 
these  are  more  conveniently  studied  in  the  analogous  esparto  derivative. 
From  the  solution  obtained  by  digesting  the  acid  on  the  resinous  pre- 
cipitate before  described,  a  peculiar  nitro-derivative  was  obtained.  Con- 
cordant analyses  of  this  body,  in  the  form  both  of  its  barium  and  cal- 
cium compound,  established  the  formula  as  CggHg^NOgglVI^^^.  In  the 
free  state  it  is  a  powerful  acid  ;  it  has  an  intensely  bitter  taste,  and  dyes 
animal  fibres  a  brilliant  yellow. — your.  Chem.  Soc.^  Sept.^  1880,  p.  667. 
EMULSION  S. 
By  a.  W.  Gerrard,  F.C.S. 
Demonstrator  of  Pharmacy  and  Materia  Medica  to  University  College. 
This  communication  is  the  result  of  some  experiments  made  with 
the  view  of  determining  what  would  prove  the  most  valuable  agents 
for  general  use  to  render  oils,  balsams,  resins  and  oleo-resins  in  the  form 
of  emulsions.  Also  to  arrange  formulae  practical  and  reliable,  for  the 
most  commonly  prescribed  substances  required  to  be  dispensed  in  the 
emulsion  form. 
The  subject,  I  know,  is  one  upon  which  much  has  been  already  said 
and  written,  and  yet,  withal,  there  exists  amongst  pharmaci  ts  a  wide 
diff'erence  of  opinion  and  practice  as  to  the  material  or  process  which 
shall  best  emulsify  any  given  oil.  The  truth  of  this  observation  may 
be  demonstrated  by  giving  the  same  prescription,  say  for  J  an  ounce  of 
castor  oil  to  be  rendered  into  2  ounces  of  emulsion,  according  to  art^ 
to  six  diff^erent  chemists  to  prepare,  the  products  will  vary  most 
astonishingly,  no  two  being  alike  either  in  color  or  fluidity,  and  some 
not  even  emulsified  at  all.  This  want  of  uniformity  in  our  art  applies 
not  only  to  emulsions,  but  various  other  preparations,  and  although 
some  slight  variations  may  be  expected  in  preparations  obtained  from 
products  themselves  subject  to  natural  variation,  the  difference  is  gen- 
rally  far  too  great  to  be  explained  on  these  grounds,  and  is  often  suffi- 
