Am.  Tour.  Pharm.  "I 
Dec,  1918.  > 
Determination  of  Morphine. 
853 
product  was  reputed  to  be  stronger  and  purer  than  that  of  the  shops 
licensed  by  the  Chinese  government. 
It  is  not  easy  to  see  why  such  a  state  of  affairs  with  respect  to  the 
assay  of  opium  and  the  determination  of  morphine  in  opium  products 
has  been  allowed  to  continue.  That  existing  methods  are  intended 
for  trade  purposes  only  is  not  an  answer,  since  it  is  for  trade  purposes 
that  some  of  our  most  accurate  analytical  methods  in  other  fields 
have  been  designed.  Morphine  has  so  high  a  value  commercially 
that  its  accurate  determination  must  be  financially  important.  Yet 
it  seems  as  though  a  lower  standard  than  should  be  allowed  has 
hitherto  been  set.  Betterment  is  demanded  both  in  the  interests  of 
business  enterprise  and  by  scientific  pride. 
In  the  present  work  the  writer  has  been  urged  by  necessities 
rising  from  successive  official  positions  which  he  has  held.  The 
results  here  presented  do  not  constitute  a  complete  solution  of  the 
problem,  but  they  appear  to  approach  nearer  to  that  end  than  any 
yet  brought  forward. 
Principles  of  the  Proposed  Method. 
The  manner  of  determining  morphine  described  in  Part  II  of 
this  communication  cannot  be  applied  to  opium  and  its  preparations, 
since  the  extraction  by  a  chloroform-alcohol  mixture  would  separate 
resinous  matter,  some  of  which  has  a  basic  character,  with  the 
morphine.  This  resinous  matter  also  accompanies  the  morphine 
when  the  latter  is  precipitated  from  alkaline  solution  by  the  addition 
of  an  ammonium  salt,  unless  alcohol  be  present,  in  which  case  a 
serious  loss  of  morphine  occurs.  But  a  great  part  of  this  resin  is 
precipitated  on  cooling  after  the  aqueous  solution  containing  it  has 
been  digested  with  salicylic  acid.  This  procedure  does  not  affect 
the  morphine,  but  is  not  in  itself  a  complete  purification.  The 
alkaloid  must  be  precipitated  from  a  concentrated  solution  in  the 
presence  of  chloroform,  no  alcohol  being  used;  it  is  then  further 
purified  by  re-solution  and  extraction  with  a  chloroform-alcohol 
mixture. 
The  only  necessary  cause  of  loss  in  the  whole  process  is  the  pre- 
cipitation, and  the  extent  of  such  loss  is  much  less  than  in  other 
methods.  The  chemical  justifiability  of  each  step  can  be  seen  by 
reference  to  the  data  collected  in  Part  I  of  this  communication. 
The  method  now  to  be  set  forth  can  be  applied  equally  well  to 
