174 
Emulsions. 
f  Am.  Joer.  Pharkl 
\    April  1,  1873„ 
it  exhibited  a  distinct  iodoform  reaction,  but  with  freshly-ignited  car- 
bonate of  potassa  no  such  reaction  was  obtained  after  the  same  lapse 
of  time. 
Ether  and  Anhydrous  Sulphate  of  Copper. — When  sharply  dried 
(dehydrated)  sulphate  of  copper  and  pure  ether  are  kept  for  six 
months  in  a  well-stoppered  bottle  the  ether  exhibits  no  physical  ap- 
pearance of  change,  but  on  testing  the  ether  it  exhibits  distinctly  the 
iodoform  reaction.  A  portion  of  the  same  ether  employed  in  these 
experiments  was  kept  alone,  and  having  been  tested  after  six  month® 
did  not  then  exhibit  any  trace  even  of  formation  of  iodoform.  I  can- 
not explain  the  reason  why  certain  neutral  and  anhydrous  substances- 
(CaCl2,NaCl,CuS04)  should  have  any  peculiar  effect  on  ether  without 
entering  into  hypotheses  which  are  not  proved  ;  it  appears  that  basic; 
substances  do  not  act  upon  ether,  while  acids  and  salts  affect  it.  We- 
might  suppose  that  ethylates  are  formed,  for  instance  : 
CuS04+CsH5OC2H6=Cu-OW_OC2H55 
and  that  by  the  operation  of  testing  for  iodoform  alcohol  is  formed 
by  the  action  of  water ;  but  it  is  also  possible  that  a  small  portion  of 
the  ether  is  converted  into  alcohol  and  ethylen.  The  main  point  of 
interest  in  these  researches  is  that  perfectly  pure  ether  can  be  kept 
by  itself  in  well-stoppered  bottles  without  alteration,  and  also  when* 
in  contact  with  perfectly  dry  and  previously  thoroughly  ignited 
KHO,CaO,K2C03,  and  also  with  pure  sodium,  but  the  ether  cannot 
be  kept  with  water,  CaCl2,NaCl,  or  CuS04,  because  when  in  contact 
with  these  substances  it  is  gradually  altered. — London  Chem.  New**. 
Jan.  24,  1873,  from  Annalen  der  Chemie  und  Pharmaeie. 
EMULSIONS. 
By  Herbert  G.  Rogerson. 
A  paper  on  emulsions,  recently  published  in  the  Druggists  Circu- 
lar, by  Mr.  P.  W.  Bedford,  was  mainly  devoted  to  a  consideration  of 
the  merits  of  a  combination  of  gum  acacia  and  glycerin,  in  the  pre- 
paration of  emulsions  of  various  kinds.  Believing,  however,  that  gum* 
tragacanth  affords  us  a  mucilage  which,  when  prepared  under  certain 
conditions,  is  capable  of  giving  results  in  every  respect  superior  te> 
any  producible  by  the  combination  recommended  in  the  paper,  I  pro- 
pose briefly  to  outline  its  more  advantageous  applications  and  ex- 
