ON  METALLIC  BISMUTH. 
165 
chemical  substances  at  present  known  when  it  is  exposed  to  the 
action  of  an  oxyhydrogen  flame,  has  never  before  been  dis- 
covered, nor  has  its  property  of  being  capable  of  agglomera- 
tion and  moulding,  either  separately  or  mixed  with  a  small  por- 
tion of  an  agglutinant  substance. — Qhem.  News,  Dec,  11,  1868. 
ON  METALLIC  BISMUTH. 
By  0.  H.  Wood,  F.C.S. 
The  issue  of  the  discussion  which  has  taken  place  in  the 
Pharmaceutical  Journal,  on  the  Liquor  Bismuthi  et  Ammoniae 
Citratis  of  the  British  Pharmacopoeia,  is  dependent  on  the  nature 
and  amount  of  the  impurities  present  in  commercial  bismuth, 
and  the  efficiency  of  the  nitre  process  for  their'removal.  Although 
several  communications  from  different  contributors  have  been 
published  upon  this  subject,  no  one  has  yet  given  any  exact 
estimate  of  the  quantity  of  impurity  which  the  metal  usually 
contains,  and  the  proportion  of  this  which  can  or  cannot  be  re- 
moved by  the  Pharmacopoeia  method. 
The  officinal  process  for  the  purification  of  bismuth  is  in  accor- 
dance with  the  method  indicated  by  most  chemical  authorities. 
Gmelin,  Watts,  and  other  authors  state  that  the  impurities  of 
bismuth  are  removed  by  fusion  with  nitre.  Mr.  Schacht's  ex- 
periments sufficiently  demonstrates  the  possibility  of  removing 
the  whole  of  the  arsenic  by  this  means.  It  is  true  that,  in  some 
fusions,  Mr.  Schacht  found  a  portion  of  the  arsenic  still  re- 
mained in  the  metal,  but  we  are  not  informed  what  the  propor- 
tions were  before  or  after,  and  we  have  every  right  to  assume 
that,  by  continuing  or  repeating  the  process,  the  whole  might 
have  been  removed  in  these  as  in  the  other  cases.  My  own  experi- 
ments have  sufficiently  satisfied  me  that  the  Pharmacopoeia 
method  is  an  efficient  one  for  the  complete  removal  of  arsenic, 
antimony,  and  sulphur.  The  most  careful  application  of  Marsh's 
test  has  failed  to  detect  either  of  the  former  substances  in  any 
sample  of  the  metal  I  have  purified. 
Mr.  Schacht  and  others,  however,  have  brought  forward  ex- 
periments to  show  that  the  nitre  process  fails  to  remove  the 
copper  from  bismuth,  and  have  urged  this  point  as  one  of  the 
