126  Ready  Test  for  Arsenical  Compounds,  {A\]™-J7Tm' 
upon  such  an  important  subject,  I  feel  it  incumbent  upon  me,  as  it 
should  be  upon  any  one,  to  speak  the  truth  and  give  expression  to  my 
honest  convictions,  "  hew  to  the  line,  let  the  chips  fly  where  they 
will." 
I  have  given  this  subject  much  thought  and  careful  consideration, 
and  have  treated  it  in  this  minute  and  thorough,  and,  I  hope,  impar- 
tial manner  which  its  importance  demands  ;  and  should  I  have,  inad- 
vertently, made  any  erroneous  statement,  I  shall  be  most  happy  to 
have  any  physician  or  pharmacist  who  may  be  more  enlightened  upon 
the  subject  than  myself,  to  correct  me. 
Philadelphia ,  Pa.,  February,  1877. 
A  READY  TEST  FOR  ARSENICAL  COMPOUNDS. 
By  Edward  Gaillard,  Ph.G. 
Read  at  the  Pharmaceutical  Meeting,  February  zoth. 
Who  is  the  pharmacist  that  has  not  been  called  upon  by  his  patrons 
or  the  physician  to  know,  at  once,  if  this  powder  or  that  liquid  did  not 
contain  ratsbane  or  arsenic,  and  often  been  obliged  to  make  some  excuse 
for  the  lack  of  knowledge,  or  felt  the  want  of  a  more  simple  and 
ready  test  for  the  detection  of  arsenic,  than  the  old,  time-honored  one 
of  Marsh's.  If  we  have  the  apparatus,  or  extemporize  one,  are  we 
positive  that  it  is  free,  at  all  time,  of  traces  of  that  metal  from  previous 
operations  ;  besides  it  labors  under  many  serious  disadvantages.  First, 
that  sulphuric  acid  ;  secondly,  that  metallic  zinc,  which  are  employed 
in  the  test,  may,  one  or  other  of  them,  or  even  both,  contain  more 
or  less  of  arsenic  as  an  impurity,  and  thus  the  indications  of  that 
substance  obtained  may  be  due  not  to  its  existing  in  the  suspected 
matter  under  investigation.  I  may  add  that  it  is  difficult  to  get,  in 
commerce,  zinc  and  sulphuric  acid  perfectly  free  from  arsenic. 
The  test  proposed  by  Edmund  W.  Davy,  professor  of  forensic 
medicine  in  the  Royal  College  of  Surgeons,  of  Ireland,  is  one  of  such 
simplicity,  and  has  proved  so  practical  in  my  hands  that  I  would 
recommend  it  to  the  pharmacist  desiring  be  to  Probus  Paratus,  always 
ready,  at  the  instant,  to  decide  at  once  when  life  and  death  depend  upon 
his  knowledge,  and  is  so  easy  of  execution  that  it  may  be  performed 
by  almost  any  one,  and  found  practical  for  the  object  stated,  especially 
to  those  who  are  not  conversant  with  the  details  of  chemical  manipula- 
