THE  AMERICAN 
JOURNAL  OF  PHARMACY. 
MAY,  1883, 
NOTES  ON  THE  PREPAKATION  OF  ARSENIC  TEIBRO- 
MIDE  AND  ITS  ADMINISTRATION. 
By  Frank  L.  Slocum. 
As  the  preparation  of  arsenious  bromide  (AsBrg),  and  more  espe- 
cially its  supposed  aqueous  solution  for  administration,  as  given  by  R. 
F.  Fairthorne/  is  wrong,  and  may  lead  to  very  erroneous  conclusions 
on  the  physiological  action  of  AsBrg,  a  correction  on  such  a  delicate 
compound  is  thought  to  not  be  out  of  place  here. 
AsBrg  was  prepared  by  J.  Nickles  in  1859.^  He  gave  complete 
directions  for  its  preparation  in  1862,^  as  follows :  To  one  part  bro- 
mine, dissolved  in  two  parts  of  carbon  disulphide,  finely  powdered 
metallic  arsenic  is  added  in  small  quantities,  each  time  shaking  till 
dissolved.  This  is  continued  until  no  further  decoloration  takes 
place,  when  the  solution  is  immediately  filtered  and  allowed  to  crys- 
tallize. Pure  AsBrg  forms  colorless  hygroscopic  crystals,  having  the 
specific  gravity  3*66  (Boedecker)  f  melting  point,  20°  to  25°C. ;  boil- 
ing point,  220°C.  It  distils  without  decomposition  and  sublimes  in 
crystals. 
The  precaution  to  be  used  in  this  method  is  to  have  the  bromine  and 
carbon  disulphide  perfectly  dry.  We  know  that  commercial  bromine 
contains  water,  chlorine,  iodine,  tetrabromide  of  carbon  and,  undoubt- 
edly, bromoform.  The  presence  of  these  last  two  are  probably  what 
gave  Mr.  Fairthorne's  aqueous  preparation  its  smell  of  chloral.  Fur- 
ther, commercial  arsenic  contains  at  least  arsenious  anhydride  (AsgOg) 
and  a  sub-oxide  (AsgO?).  Each  of  these  impurities  by  Mr.  Fair- 
thorne's process  leads  to  a  product  of  a  different  composition  than  • 
AsBrg,  as  we  will  see  farther  on,  and  also  gives  a  finished  product 
which  must  invariably  contain  either  an  excess  of  free  bromine  or 
1  'Am.  .Tour.  Phar      1883,  p.  143. 
2 "  Compt.  Rend.,"  48,  p.  837. 
"Jour.  Phar.  et  Chim."  [3],  41,  p.  142. 
*  "  Jahrebbericht  Chem.,''  1860,  p.  17. 
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