616 
Iodine  in  Cod  Liver  Oil. 
•"Am.  Jour  Pharm. 
\       Dec,  1883. 
the  quantity  of  oil  used  in  the  other  experiments.  It  contains  one 
hundred  and  eighty  seven  times  the  proj^ortion  of  iodine. 
Per  cent. 
Fulmar  oil  contains  iodine  0-000095 
Cod  liver  fresh  contains  iodine  0*000817 
Cod  liver  oil  drag6es  contain  iodine  0"056366^ 
It  will  be  noticed  that  the  fresh  cod  liver  contains  more  than  double 
as  much  iodine  as  the  mean  percentage  in  the  oil.  Mr.  Gate  has  kindly 
sent  me  an  estimate  of  the  yield  from  his  experience  of  ten  year's 
average  of  oil  from  cod  liver  ;  it  is  about  45  per  cent.,  taking  the  best 
time,  December.  The  inference  is  that  the  liver  without  the  oil 
would  contain  a  much  higher  percentage  of  iodine,  as  shown  indeed  in 
the  dry  dragees.  And  I  shall  not  be  surprised  to  find  as  much  in  the 
fish.    This  point  is  under  investigation. 
Scotch  herring  has  been  said  by  Jonas"  to  contain  iodine,  and  this 
is  also  under  investigation. 
This  morning  I  have  received  the  results  of  the  analysis  of  fresh 
cod,  herring,  and  herring  brine. 
5,000  grains  of  fresh  cod  were  treated  with  500  grains  caustic  soda. 
5,000  grains  of  salt  herrings  were  treated  with   "  " 
2  5,000  grains  of  herring  brine  were  treated  with...         "  " 
Fresh  codfish  contained  "00016  per  cent,  iodine  dry  =  '000829. 
Scotch  herring  salted  contained  '00065  per  cent,  iodine. 
"  brine        "        -00012      "  " 
The  codfish  contained  80-7  per  cent,  water. 
In  the  fresh  codfish  the  analyst  for  the  first  time  in  these  experi- 
ments was  troubled  with  a  large  quantity  of  sulphides,  and  in  this  case 
only  was  not  satisfied  wiih  the  indication  from  500  grains  measure,  and 
was  obliged  to  use  the  larger  quantity. 
It  will  be  seen  that  the  herring  contains  four  times  the  amount  of 
iodine  contained  in  the  codfish,  and  more  than  in  any  of  the  samples 
of  cod  liver  oil ;  if,  therefore,  the  iodine  be  the  medicinal  element,  you 
should  recommend  Scotch  herring  salted ,  it  is  very  cheap  at  present. 
I  find  the  subject  becoming  interesting,  and,  indeed,  alarming  to  the 
iodine  maker,  and  intend  examining  other  varieties  of  fresh  fish,  for 
^  In  the  published  analysis  of  these  by  Professor  Garreau  the  iodine  is 
estimated  at  0  154  per  cent.,  richer  than  any  other  known  organic 
substance. 
Two  determinations  were  made,  one  with  500  grains  and  another  with 
4,500  grains,  and  the  mean  taken. 
