Am.  Jour.  Pharm. ) 
July,  1890.  J 
Cod  Liver  Oil. 
367 
ciples  from  cod  liver  oil,  the  authors  treated  100  kilograms  of  oil 
methodically  with  an  equal  volume  of  350  alcohol,  containing  3 
grams  of  oxalic  acid  per  litre.  The  oil  was  shaken  with  the  alcohol 
in  twenty  glass  bottles  each  of  fifteen  litres  capacity,  the  free  part  of 
which  was  filled  with  carbonic  acid  to  avoid  the  action  of  air  upon 
the  oil.  After  standing,  the  alcoholic  liquid  was  siphoned  off, 
exactly  neutralized  with  milk  of  lime  and  evaporated  in  vacuo  at  a 
temperature  not  exceeding  400  C.  Under  these  conditions  the 
mixture  remained  limpid  and  nearly  colorless.  When  it  had  been 
reduced  to  one  hundredth  of  its  original  volume  it  was  neutralized 
by  precipitated  calcium  carbonate,  filtered,  and  the  desiccation 
finished  in  vacuo. 
If  it  be  desired  simply  to  extract  from  this  residue  the  total  basic 
substances  it  contains,  without  regard  as  to  the  manner  in  which 
they  are  combined,  the  product  of  the  evaporation  is  treated  with 
So°  alcohol,  and  the  extract  is  filtered  or  distilled  until  all  the 
alcohol  has  passed  over  and  concentrated  in  vacuo.  In  this  way  a 
syrupy  extract  is  obtained  to  which  caustic  potash  is  added  in  frag- 
ments to  liberate  the  bases.  These  are  separated  by  shaking  the 
mixture  with  ether,  then  precipitating  the  bases  from  the  ethereal 
solution  by  means  of  an  ethereal  solution  of  oxalic  acid,  washing 
the  precipitate  with  ether  and  drying.  The  scarcely  colored  dry 
oxalates  obtained  from  100  kilograms  of  oil  weighed  52  grams. 
In  order  to  obtain  the  bases  free,  the  salt  is  dissolved  in  the 
smallest  quantity  of  water  and  the  solution  is  treated  with  caustic 
potash.  Under  this  treatment  the  alkaloids  usually  rise  to  the  sur- 
face like  a  thick  brown  oil,  which  is  due  to  the  solution  of  two  fixed 
bases  in  the  oily  bases. 
The  treatment  with  alcohol,  acidulated  with  oxalic  acid,  removes 
from  the  oil  nearly  the  whole  of  the  bases.  In  the  authors'  experi- 
ments the  quantity  obtained  varied  between  0  380  gram  and  0-485 
gram  per  kilogram  of  the  brown  oils ;  but  from  the  pale  oils  the 
yield  was  inappreciable,  even  when  operating  upon  ten  kilograms. 
If  account  be  taken  of  the  fact  that  a  trace  of  basic  substances 
remain  in  the  oil  after  treatment  with  acidulated  alcohol,  it  will  be 
seen  that  the  total  bases  contained  in  a  kilogram  of  brown  oil 
amounts  to  about  half  a  gram.  That  would  be  about  6-5  milligrams 
of  base,  or  10  milligrams  of  the  sulphates  in  each  tablespoonful 
\l3  grams)  of  oil,  a  quantity  that,  considering  the  powerful  action  of 
these  bases,  cannot  be  without  effect  on  the  economy. 
