COCAINA,  THE  ACTIVE  PRINCIPLE  OF  COCA. 
407 
ence  of  much  alcohol ;  the  double  salt  separates  then  little  by 
little  in  long  orange  yellow  prisms. 
This  mutability  of  cocain  offers  an  explanation  of  the  fact  that 
attempts  to  obtain  that  principle  by  operating  on  coca  with  acid 
liquids  have  failed.  Perhaps,  also,  this  alkaloid  is  subjected  to 
an  injurious  transformation  in  old  leaves.  From  this  action  of 
chlorohydric  acid  it  can  in  all  cases  be  inferred  that  it  is  neces- 
sary to  avoid  the  presence  of  free  acids  in  preparing  cocaina 
from  coca  leaves. 
The  following  is  the  process  recommended  by  M.  Lossen : 
The  leaves  having  been  digested  several  times  at  140°  to  176°, 
the  aqueous  infusions  are  united,  precipitated  by  acetate  of  lead, 
filtered,  and  the  lead  removed  by  means  of  sulphate  of  soda,  and 
the  liquid  concentrated  in  a  water  bath.  Then  carbonate  of  soda 
is  added,  and  the  whole  shaken  with  ether.  This  is  decanted, 
and  the  ether  renewed  five  or  six  times  ;  the  alkaloid  is  dissolved 
in  the  ether,  which  is  regained  by  distillation.  The  residue  on 
standing  yields  crude  cocaina,  which  is  purified  by  first  triturat- 
ing it  with  cold  water  to  remove  the  coloring  matter,  and  in  sub- 
mitting it  afterwards  to  the  treatment  already  described  by  M. 
Niemann.  The  purer  the  cocaina  is,  the  more  easily  it  crystal- 
lizes in  ether,  and  gives  at  the  same  time  very  handsome  rhom- 
boidal  prisms. 
Amylic  alcohol  is  less  favorable  to  this  extraction,  but  its  em- 
ployment has  conducted  to  the  discovery  of  a  new  liquid  alka- 
loid, hygrina*  volatile,  and  capable  of  being  distilled  with  water. 
Its  odor  recalls  that  of  trimethylamin.  It  has  a  strong  alkaline 
reaction,  and  gives  white  fumes  with  volatile  acids. 
The  muriate  of  hygrina  is  crystallizable,  but  very  deliquescent ; 
the  chloroplatinate  is  a  yellow  flocculent  uncrystallizable  pre- 
cipitate which  decomposes  at  ebullition. 
With  bichloride  of  mercury  this  alkaloid  produces  a  milky  dis- 
coloration occasioned  by  oily  drops. 
It  appears  also  to  be  evolved  when  coca  is  heated  with  caustic 
lye  in  milk  of  lime. 
Hygrina  is  not  poisonous. — Jour,  de  Pharm.,  Juin,  1862, 
from  Ann.  der  Chem.  und  Pharm.,  t.  cxxi.,  p.  372. 
*  From  uypoc,  liquid. 
