LIQUOR  BISMUTHI. 
151 
from  the  recent  and  dried  root.  My  opinion  is  that  the  prepara- 
tion from  the  dried  root  contains  all  or  nearly  all  the  active 
matter  of  the  drug,  and  that  there  is  no  necessity  for  recom- 
mending the  fresh  root  to  be  used  in  this  case.  All  such  in- 
structions should,  I  believe,  be  avoided  where  possible,  since 
their  tendency  is  to  confine  the  manufacture  of  the  article  chiefly 
to  the  localities  where  the  root  grows  most  abundant — an  ar- 
rangement for  many  reasons  not  desirable. 
Samples  are  herewith  submitted.  No.  1,  is  the  oil  of  my  own 
preparation.  No.  2,  that  purchased  in  Cincinnati.  No.  3, 
contains  the  product  remaining  after  the  exposure  of  the  Cincin- 
nati oil  to  the  action  of  the  air. — Proc.  Am.  PJiar.  Assoc.  1868. 
LIQUOR  BISMUTHI. 
By  George  F.  H.  Markoe. 
The  writer  has  been  called  upon  to  prepare  this  solution  quite 
frequently,  and  in  considerable  quantities,  and  after  a  careful 
trial  of  all  the  published  formulas  for  its  manufacture  has  found 
some  objection  to  all  of  them.  The  writer  cheerfully  acknowl- 
edges his  indebtedness  to  Mr.  N.  Gray  Bartlett,  to  whom  we 
owe  the  first  good  working  formula  given  in  the  Am.  Jour. 
Pharm.^  Jan.,  1865.  Mr.  Albert  E.  Ebert,  in  the  same  jour- 
nal, Jan.,  1866,  gives  an  improvement  on  Mr.  Bartlett's  process 
by  which  he  avoids  the  use  of  crystallized  citrate  of  potassa, 
and  forms  the  citrate  of  bismuth  by  adding  citric  acid  to  the 
nitrate  of  bismuth  and  then  adding  hydrate  of  potassa,  by 
which  means  citrate  of  bismuth  is  precipitated  and  nitrate  of 
potassa  is  obtained  in  solution,  and  is  got  rid  of  by  washing  the 
bismuth  salt  on  a  filter.  Ebert's  process  is  a  good  one,  indeed 
the  best  that  has  been  published,  and  the  only  objection  the 
writer  has  to  it  is  the  use  of  caustic  potassa  to  neutralize  the 
nitric  acid.  The  idea  of  adding  the  citric  acid  to  the  solution 
of  nitrate  of  bismuth,  must  in  justice  be  credited  to  Mr.  Thos. 
P.  Blunt,  who  first  suggested  it  in  the  Lond.  Pharm.  Journ.^ 
May,  1865. 
The  objections  to  caustic  potassa  are,  that  great  care  must  be 
used  to  avoid  an  excess,  from  the  fact  that  citrate  of  bismuth  is 
