572  New  Constituent  of  Liver  Oil,  {^"^'iow^/Jm''^' 
colorations  with  orcin^  on  which  account  such  additions  are  to  be 
avoided. 
In  the  following  table  the  color  reactions  of  orcin  with  various  sub- 
stances tested  are  described : — 
Gum  Arabic  
Gum  Tragacantli  
Gum  Senegal  
Potato  Starch  
Maranta  Starch  
Triticum  Starch  
Milk  Sugar  
Beet  Sugar  
Cane  Sagar  
Gelatin  
Pepsin  
Pancreatin  
Albumen,  fresh  
Albumen,  boiled,  dissolved 
in  Pepsin  
Albumen,  boiled,  dissolved 
in  Pancreatin  
Residue  from  alcoholic  solu- 
tion of  Liver  Oil  
Pure  Orcin  
Evaporation   I  Solution 
residue.  Alcohol. 
Green 
Green-black 
Greenish-blue 
Red 
Red 
Yellow  red 
Brown-red 
Brown 
Brown 
Red 
Yellow 
Brown 
Yellow-brown 
Yellow 
Brown 
Brown 
Red 
Green-yellow 
Green-yellow 
Green-yellow 
Light-brown 
Brown 
Light-brown 
Yellow-brown 
Yellow-brown 
Yellow-brown 
Yellow-red 
Yellow 
Light  brown 
Light-brown 
Light-brown 
Light- brown 
Light-brown 
Rose 
Addition 
of 
Ammonia. 
Green-yellow 
viofet. 
Brown. 
Green-yellow. 
Violet-yellow. 
Brown. 
Brown. 
Greenish-brown. 
Brown. 
Brown. 
Violet. 
Dark-yellow. 
Rose-violet. 
Brown. 
Brown. 
Brown-violet. 
Brown  green. 
Violet. 
According  to  this  comparison  the  residue  from  liver  oil  showed 
most  resemblance  to  pancreatin  and  albumen  that  had  been  dissolved 
by  pancreatin.  This  suggested  the  idea  of  seeking  the  new  substance 
in  fresh  pancreatic  liquor. 
Fresh  aqueous  pressings  from  pancreas  glands  were  precipitated 
with  alcohol,  the  precipitate  washed  with  alcohol,  then  dissolved  in 
water,  and  again  precipitated,  washed  and  redissolved  in  water.  The 
resulting  solution  rotated  a  polarized  ray  to  the  left  and  reduced  alka- 
line copper  solution.  By  evaporating  over  sulphuric  acid  a  non-crys- 
talline residue  was  obtained.  It  was  therefore  considered  probable 
that  the  two  substances  from  liver  oil  and  pancreatic  juice  were  iden- 
tical, and  this  assumption  was  made  tolerably  certain  by  a  comparison 
of  the  influence  of  the  two  substances  upon  fixed  oils.  A  few  cubic 
centimetres  of  the  solutions  mixed  with  any  of  the  fatty  oils  acted  so 
that  the  oil  could  be  temporarily  emulsified  with  half  its  volume  of 
