194  PREPARATION  OF  MISTURA  FBRRI  COMPOSITA. 
acrid  emetic  substance.  What  was  there  on  the  shelves  of  the 
apothecary,  of  this  poisonous  character,  likely  to  be  substituted 
for  the  proper  ingredients  of  this  mixture  ? 
The  presence  of  myrrh  was  too  apparent  to  be  denied.  The 
spirit  of  lavender  might  be  present ;  but  liquor  potassse  arseni- 
tis,  if  substituted^  would  be  accompanied  by  its  constituent  com- 
pound spt.  of  lavender.  This,  however,  was  not  probably  the 
poisonous  article,  as,  by  calculation,  the  patient  took  less  than 
four  minims  of  this  constituent  in  a  dose,  and  the  second  dose 
was  taken  six  hours  after  the  first.  But,  if  the  arsenical  solution 
had  been  mistaken  for  the  rose-water,  fifty-six  minims  would  have 
been  swallowed  at  a  dose.  In  this,  however,  it  was  improbable 
that  the  error  lay,  for  aside  from  any  assuasive  influence,  the  car- 
bonate of  iron,  if  present  in  the  mixture,  would  have  upon  the 
arsenical  poison,  the  odor  of  the  peppermint  water,  which  was 
intentionally  used  instead  of  rose  water,  was  very  distinguisha- 
ble. 
As  to  the  solids  in  the  preparation  in  question,  (carbonate  of 
potash,  sugar,  and  sulphate  of  iron,)  one  or  more  of  the  salts  of 
antimony,  lead  and  zinc,  or  arsenious  acid,  or  corrosive  subli- 
mate, might  have  been  substituted  for  them. 
By  the  aid  of  Trommer's  test,  I  satisfactorily  determined  the 
presence  of  sugar  in  the  medical  mixture. — By  the  way,  I  will 
state  that  for  the  same  purpose  I  tried  Donaldson's  test,  which 
I  prepared  in  1852;  (Amer.  Jour,  of  Pharm.  vol.  24  ;)  but  it 
was  not  reliable ;  the  results  being  almost  precisely  the  same  in 
an  aqueous  solution  of  myrrh,  as  in  the  medical  preparation. 
Donaldson's  reagent,  though  very  active  when  recently  made,  is 
not  a  permanent  compound. — Sugar,  therefore,  being  present, 
the  apprehended  mistake  was,  in  all  probability,  in  respect  to  the 
carbonate  of  potash  or  sulphate  of  iron.  In  one  fluid  drachm  of 
the  medicine,  (the  dose  was  only  a  teaspoonful,)  there  would  be 
a  small  fraction  over  three-tenths  of  a  grain  of  the  chalybeate 
salt ;  (exactly  .3125  gr ;)  and  less  than  four-tenths  of  a  grain  of 
the  alkaline  carbonate.  The  same  quantities  of  the  salts  of  zinc, 
lead,  or  antimony,  could  hardly  produce  the  pathogenetic  effects 
which  the  patient  experienced ;  and  neither  these,  nor  arsenious 
acid,  or  corrosive  sublimate  would  produce,  by  any  reaction  with 
the  other  constituents  of  the  medical  preparation,  the  bluish 
