142 
NOTES  ON  LIQUOR  BISMUTHI. 
The  writer  has  used  Mr.  Bartlett's  process  many  times,  and 
always  with  good  results,  but  considers  the  modifications  sug- 
gested by  Mr.  A.  E.  Ebert,  published  in  the  Am.  Jour.  Pharm., 
Jan.,  1866,  of  much  practical  advantage,  as  it  shortens  the  pro- 
cess, especially  the  washing  of  the  citrate  of  bismuth  on  the  filter, 
which  is  at  best  a  tedious  operation. 
The  writer  has  but  one  new  point  to  suggest,  and  that  is  with 
regard  to  an  improved  method  of  assaying  the  bismuth  solution. 
Sulphide  of  ammonium  and  sulphydric  acid  are  the  reagents 
usually  employed  in  the  assay  of  bismuth  solutions  and  give  very 
good  results,  but  they  both  possess  a  most  disgusting  odor.  The 
writer  has  found  that  sulphide  of  sodium,  while  it  gives  excellent 
results,  equal  in  accuracy  to  those  obtained  by  the  use  of  the  first 
named  reagents,  has  the  advantage  of  giving  a  denser  and  hence 
a  more  easily  washed  precipitate  of  ter-sulphide  of  bismuth.  It 
has  but  little  odor  and  can  be  used  in  the  shop  or  laboratory  with- 
out filling  the  atmosphere  of  the  room  with  the  smell  of  sulphu- 
retted hydrogen.  The  point  of  saturation  is  readily  determined, 
and  the  sulphide  of  bismuth  formed  is  absolutely  insoluble  in  an 
excess  of  the  precipitant. 
Sulphide  of  sodium  may  be  prepared  by  the  following  formula  : 
Take  of  solution  of  soda  three  parts,  and  conduct  sulphydric 
acid  gas  into  the  solution  as  long  as  it  is  absorbed,  and  when  the 
saturation  is  complete  add  two  more  parts  of  solution  of  soda 
and  keep  the  sulphide  of  sodium  in  well  stopped  bottles. 
With  a  view  to  test  the  value  of  sulphide  of  sodium  as  a  reagent 
a  number  of  assays  of  commercial  samples  of  liquor  bismuthi 
were  made.  Both  of  the  samples  were  of  New  York  make,  and 
are  furnished  to  the  trade  in  pound  bottles. 
No.  1.  A  colorless  liquid  with  a  sweet  taste  and  the  flavor  of 
caraway,  leaving  an  after- taste  of  metallic  character.  The  specific 
gravity  at  60°  was  1*45.  Four  assays  of  this  solution  were  made 
by  precipitating  the  bismuth  as  ter-sulphide  by  means  of  an  ex- 
cess of  sulphide  of  sodium,  and  the  average  results  of  these  assays 
were  eight  and  one-half  grains  of  ter-sulphide  of  bismuth  from 
each  fluid-ounce,  equal  to  seven  and  seven-tenths  grains  of  ter- 
oxide  of  bismuth,  or  fifteen  and  four-tenths  grains  of  ammonio- 
citrate  of  bismuth.    This  solution,  then,  is  just  what  it  purports 
