43-  The  Opium  Assay  Method. 
iporphine  is  incurred  by  this  manipulation.  The  results  are  tabu- 
lated and  necessary  explanations  follow : 

No.  1. 
No.  2. 
No.  3» 
No.  4» 
"Mr*  c 
Hours  allowed  for  the  pre-  "| 
cipitation  of  the  mor-  [ 
phine.  j 
17 
18 
41 
41 
Quantity  (cc.)  of  wash  water") 
used.  j 
15 
20 
20 
30 
30 
Weight  of  crude  morphine  1 
on  weighed  filter.  j 
1  "6315 
1-5675 
i'5595 
1*5495 
I-5075 
VVClgJJIL    Ul     ad-UlC    Oil    WatLfl  I 
crystal.  J 
1-560 
1-526 
1-498 
1-479 
1-454 
Impurity  taken  up  by  the  \ 
weighed  filter.  j 
0'07T 
n'n/i  t  ? 
0  "0615 
u  uOOJ 
Ash  as  CaC03  from  I  gram  1 
crude  morphine.  ] 
0-052 
0-0505 
0*042 
O  0425 
0-0425 
Ash  X  2-56  =  calcium  me  | 
conate  ;  calculated  for  en-  V 
tire  weight  of  morphine.  J 
0-208 
0-197 
o*i6i 
0-161 
0-I58 
Corrected  weight  of  mor-  \ 
,  phine.  j 
I '352 
1-329 
i"337 
i'3i8 
1*296 
In  washing  the  morphine  from  Nos.  1-3  with  water,  it  was  noticed 
that  the  washings  were  turbid,  and  that  after  mixing  with  the 
mother-liquor,  a  very  distinct  and  increasing  precipitate  commenced 
to  form,  so  that  in  Nos.  4  and  5,  the  mother-liquors  and  washings 
were  collected  separately ;  this  procedure  enabled  me  to  show  that 
by  keeping  these  mother-liquors  for  about  a  month,  only  a  very 
slight  further  precipitation  took  place,  while  in  the  washings  a  very 
notable^quantity  of  a  fine  whitish  or  pale  brownish  precipitate  sepa- 
rated in  a  very  short  time,  this  apparently  was  part  of  the  precipi- 
tate collected  upon  the  filter  and  caused  to  run  through  the  filters 
after  the  mother-liquor  was  replaced  by  the  wash  water ;  the  differ- 
ences in  weight  of  the  crude  morphine  are  undoubtedly  due,  in  part 
at  least,  to  the  varying  quantities  of  water  used  in  washing,  which 
removed  not  only  more  or  less  of  the  coloring  matter,  but  also  more 
or  less  of  the  above  fine  precipitate;  attempts  to  collect  this  fine 
precipitate  upon  a  filter  were  only  partly  successful,  as  a  consider- 
able portion  ran  through  the  filter ;  it  was  afterward  obtained  by 
