AjanuaryPih899.DU,|    Emetine  Octoiodide  and  Alkaloids.  15 
again,  the  same  filtered  solution  may  be  taken,  using  standardized 
acid  in  excess  and  estimating  the  excess  by  means  of  standardized 
alkali.  The  only  drawback  to  this  method  of  extraction  is  the 
great  difficulty  of  preventing  loss  by  evaporation  of  the  highly  vol- 
atile solvent,  by  which  loss  the  volume  of  the  aliquot  part  becomes 
reduced  and  the  final  figure  is  liable  to  be  too  high. 
A  GENERAL  METHOD  OF  EXTRACTION. 
In  order  to  avoid  this  difficulty  we  have  worked  out  an  entirely 
different  method  of  alkaloidal  extraction,  which  can  also  be  used 
with  any  one  of  the  methods  of  estimation  as  desired.  In  its  main 
features  this  method  is  the  same  as  that  which  we  proposed  for  the 
assay  of  opium.4    It  is  carried  out  in  the  following  manner : 
One  to  four  grams  of  the  finely-powdered  drug  is  weighed  into 
a  low  wide-mouthed  vessel  with  a  round  bottom,  holding  eight  or 
ten  ounces,  and  having  a  well-fitting  cork,  such  as  a  screw-top  oint- 
ment-jar.5 The  powder  is  rubbed  up  with  a  small  pestle  to  a  fine 
paste  by  adding  a  little  of  an  ethereo-ammoniacal  mixture,  com- 
posed of  stronger  ammonia  water  and  alcohol  each  5  c.c.,  chloro- 
form 10  c.c.  and  ether  20  c.c.  Then  a  few  more  cubic  centimeters 
of  this  mixture  are  added,  so  as  to  have  the  drug  well  covered  with 
the  liquid,  using  in  all  about  five  times  the  amount  of  the  drug 
taken.  The  vessel  is  corked,  with  the  pestle  inside,  and  is  set  aside 
for  about  four  or  five  hours,  taking  care  to  agitate  by  circular  move- 
ment very  frequently  during  that  interval.  After  that  time  the 
cover  is  removed  and  the  vessel  kept  in  a  current  of  air,  stirring 
frequently  till  all  odor  of  ammonia  has  disappeared.  With  a  good 
draught  and  frequent  stirring  the  powder  will  be  almost  perfectly 
dry  in  about  two  hours.  The  vessel  is  then  put  into  a  vacuum 
desiccator  over  sulphuric  acid  for  about  four  or  five  hours. 
Any  amount  of  powdered  sodium  chloride  equal  to  about  five  or 
six  times  the  amount  of  drug  employed  is  then  carefully  mixed  in, 
with  use  of  the  pestle,  and  the  whole  thrown  into  a  small  per- 
colator, one  provided  with  a  glass  stop-cock  and  having  a  plug  of 
cotton  at  the  bottom.6    The  vessel  is  then  cleaned  out  several  times 
J.  Am.  Chem.  Soc,  1898,  vol  20,  p.  724;  Pharm.  Archives,  1898,  p.  121. 
4 
5  An  ordinary  teacup  fitted  with  a  specie  cork  answers  well. 
6  A  suitable  percolator  is  easily  made  out  of  an  ordinary  piece  of  glass  tubing 
fitted  with  a  perforated  cork,  through  which  passes  a  tube  having  a  glass  stop- 
cock. 
