IODIDE  OF  CADMIUM.  79 
merce  is  by  no  means  an  unfrequent  occurrence  5  and  I  think 
that  many  of  my  hearers,  if  they  examined  the  specimens  in 
their  possession,  would  find  my  statement  correct.  Whether  the 
contamination  is  intentional  or  not  on  the  part  of  the  manufac- 
turers I  have  no  means  of  ascertaining.  At  present,  I  believe, 
there  is  no  object  in  making  such  addition  as  far  as  price  is  con- 
cerned, but  I  am  informed  that  the  bromide  containing  iodine 
crystallizes  in  much  larger  crystals,  and  forms  a  better-looking 
article  than  when  free  from  such  admixture.  My  own  examina- 
tion of  different  specimens  would  lead  me  to  think  that  such  is 
the  case. 
As  I  consider  the  subject  of  the  purity  of  bromide  of  potassium 
one  of  great  importance,  seeing  that  the  drug  will  probably  be 
extensively  employed  in  medicine,  I  have  been  induced  to  bring 
it  under  the  notice  of  the  Pharmaceutical  Society,  knowing  how 
much  the  Society  has  already  done  towards  improving  the  state 
of  Pharmacy  in  this  country,  and  how  anxious  the  members  are 
to  ensure  the  dispensing  of  pure  drugs — a  desideratum  alike  im- 
portant to  the  Physician  and  Pharmacopolist. — London  Pharm. 
Jour.,  Nov.  2,  1857. 
IODIDE  OF  CADMIUM. 
By  A.  B.  Garrod,  M.  D. 
Within  the  last  three  years  I  have  made  a  somewhat  extensive 
trial  of  iodide  of  cadmium  as  an  external  remedial  agent,  and,  as 
far  as  my  experience  goes,  have  reason  to  be  fully  satisfied  with 
the  results.  I  think  also  that  it  may  prove  an  addition  of  some 
value  to  the  list  of  our  Materia  Medica.  I  had  previously  felt 
the  want  of  an  agent  containing  iodine,  and  fitted  for  external 
application,  those  usually  employed  having  many  objections.  The 
free  iodine,  or  iodine  combined  with  iodide  of  potassium,  as  occurs 
in  unguentum  iodinii  compositum,  Ph.  L.,  is  frequently  too  irri- 
tant in  its  nature,  besides  which,  its  disagreeable  odor,  and  the 
staining  of  the  cuticle  which  it  produces,  is  often  very  objection- 
able. 
The  simple  iodide  of  potassium  ointment  as  ordinarily  dis- 
pensed, is  gritty  in  character,  often  to  such  an  extent  as  to  ren- 
der its  application  to  delicate  skins  impracticable,  and  it  not 
