376  Determination  of  Hydras  tine.  {Am'illT'Jmim' 
Without  going  into  the  tiresome  details  of  many  experiments  the 
process  finally  found  to  give  the  best  results  was  the  following  : 
Into  an  Erlenmeyer  flask  of  at  least  4  ounces  capacity  is  put  25  cc. 
of  the  fluid  extract.  This  is  heated  on  the  water-bath  to  a  point 
considerably  short  of  boiling.  Ten  cubic  centimetres  of  ether  are 
now  slowly  and  carefully  added  so  as  not  to  cause  loss  by  violent 
ebullition  and  lastly  25  cc.  of  a  2  per  cent,  ammonia  solution,  or  a 
mixture  of  20  cc.  of  water  with  5  cc.  of  ammonia.  The  contents  of 
the  flask  are  rotated  briskly  for  a  few  seconds  and  the  whole  then 
set  aside  for  12  hours,  frequently  rotating  during  the  first  two  or 
three  hours.  After  12  hours  the  liquid  is  poured  off  into  a  funnel, 
into  the  heck  of  which  a  small  plug  of  cotton  has  been  loosely 
inserted  and  the  whole  dried  and  weighed.  When  the  liquid  has 
all  passed  through,  the  crystals  remaining  in  the  flask  are  carefully 
rinsed  into  the  funnel  and  washed  with  distilled  water  until  the 
washings  pass  off  free  of  color.  The  funnel  and  contents  are  now 
dried  at  a  temperature  not  exceeding  ioo°  C,  cooled  in  a  desiccator 
and  weighed.  Subtracting  from  this  weight  the  weight  of  funnel 
and  cotton  gives  the  amount  of  alkaloid  obtained. 
The  fluid  extract  operated  upon  in  all  experiments  was  made 
with  dilute  alcohol  and  consequently  after  the  addition  of  an  equal 
volume  of  ammonia  solution  the  mixture  would  contain  approxi- 
mately 25  per  cent,  by  volume  of  officinal  alcohol.  This  was  found 
to  give  the  most  satisfactory  results,  all  proportions  having  been 
tried  from  50  per  cent,  down  to  10  per  cent.  The  officinal  F.  E. 
Hydrastis  is  made  with  a  mixture  of  3  parts  of  alcohol  and  1  of 
water,  which  would  necessitate  the  preliminary  evaporation  to  19 
cc.  or  else  the  addition  of  50  cc.  of  ammonia  solution  in  order  to 
reach  the  same  proportion. 
The  addition  of  ether  to  a  hot  liquid  naturally  results  in  the  loss 
of  a  large  portion  of  it,  but  enough  remains  to  saturate  the  liquid 
which  is  all  that  is  required.  An  excess  of  ether  causing  the 
separation  of  an  ether  layer  should  be  avoided. 
Agitation  is  necessary  as  it  facilitates  the  separation  of  alkaloid 
but  violent  shaking,  especially  at  the  time  when  crystallization  is 
actively  going  on,  must  be  avoided,  as  it  results  in  the  formation  of 
many  small  crystals  that  are  apt  to  pass  through  the  cotton  and  be 
lost.  The  production  of  large  crystals  must  be  aimed  at  and  when 
the  process  is  properly  conducted  they  can  be  obtained  from  j£  to 
y%  of  an  inch  or  more  in  length. 
