398 
Comparison  of  Acetic  Ethers. 
Am.  Jour.  Pharm. 
Aug..  1891. 
of  tincture  of  litmus  were  added  and  10  drops  of  the  acetic  ether, 
then  agitated,  when  in  the  presence  of  acid,  the  liquid  would  become 
pink.  -All  the  ordinary  commercial  samples  with  this  test,  gaVe 
evidence  of  acid  reaction.  The  boiling  point  was  ascertained  by 
gradually  heating  by  means  of  a  water  bath,  about  5  cc.  of  acetic 
ether  contained  in  a  long  test  tube  in  which  a  few  fragments  of 
granulated  zinc  were  previously  placed,  the  bulb  of  the  thermometer 
being  immersed  in  the  liquid,  the  point  at  which  ebullition  com- 
menced was  noted.  The  specific  gravity  was  taken  by  means  of  a 
100  grain  specific  gravity  bottle. 
On  looking  over  the  table,  the  great  variation  in  specific  gravities 
and  boiling  points  will  be  noticed ;  in  no  instance  do  the  ordinary 
specimens  fill  the  requirements  of  the  U.  S.  P.,  which  are  :  A  sp.  g. 
of  -889--897,  and  boiling  point  of  760  C. 
None  of  the  ordinary  specimens  examined  would  form  a  clear 
solution  with  benzol,  chloroform  or  an  equal  bulk  of  bisulphide  of 
carbon  ;  this  was  due  to  the  presence  of  a  larger  or  smaller  propor- 
tion of  water.  The  8  specimens  under  comparison  showed  the  fol- 
lowing behavior  :  On  shaking  15  cc.  of  acetic  ether  in  a  graduated 
tube  with  15  cc.  of  chloroform  (which  was  previously  saturated  with 
water  by  shaking  it  with  that  liquid  and  filtering)  Nos.  I  and  2  gave 
clear  solutions. 
Nos.  3,  5  and  6,  separated,  1    cc.  or  6'6  per  cent,  water. 
No.   4,  separated  8    cc.  or  5-3       "  " 
Nos.  7  and  8,  separated,  1*5  cc.  or  10  " 
On  shaking  10  cc.  of  acetic  ether  in  a  graduated  tube  with  10  cc. 
of  water  at  a  temperature  of  15-5°  C,  the  following  separation  took 
place:  No.  1,  9-2  cc.  ;  No.  2,  8  cc. ;  No.  3,  3  cc. ;  No.  4,  7  cc. ;  No.  5, 
6- 5  cc.    Nos.  6,  7  and  8  did  not  separate. 
The  several  samples  were  also  examined  for  fusel  oil  by  carefully 
pouring  a  thin  layer  of  acetic  ether  on  some  colorless  sulphuric  acid 
(1-82)  in  a  test  tube,  and  allowing  them  to  remain  in  contact  for 
half  an  hour,  the  absence  of  any  red  or  pink  color  was  taken  as 
proof  of  the  absence  of  fusel  oil. 
Acetic  ether  is  sometimes  contaminated  with  butyric  ether  ;  this 
impurity  may  be  detected  by  the  following  method  :  1  cc.  of  acetic 
ether  is  saponified  with  3  cc.  of  a  saturated  solution  of  sodium 
hydrate,  by  the  aid  of  a  moderate  heat;  when  the  odor  of  acetic 
ether  has  disappeared,  5  cc.  of  water  are  added,  and  then  super- 
