ADULTERATED  POWDERED  SOCOTRINE  ALOES. 
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duced  a  white  precipitate;  sulphate  of  copper  a  blueish  white, 
and  nitrate  of  silver  a  dense  white  precipitate,  which  were  all 
soluble  in  nitric  acid.  These  experiments  prove  that  the  pre- 
cipitated matter  found  in  the  vials  was  oxalate  of  iron ;  a  result 
not  at  all  surprising,  when  we  reflect  that  the  solution  of  ter- 
sesqui-nitrate  of  iron,  as  suggested  by  Prof.  Procter,  contains, 
in  order  to  preserve  it,  a  small  excess  of  acid,  which  in  the  syrup 
reacts  with  the  sugar  and  forms  saccharic  and  oxalic  acids,  and 
nitric  oxide:  the  first  two  unite  with  the  sesqui-oxide  of  iron, 
forming  saccharate  and  oxalate  of  that  metal  ;  the  nitric  oxide 
being  set  free  occasions  the  expulsion  of  the  corks  and  bursting 
of  the  vials,  already  referred  to. 
Some  syrup  of  the  pro/o-nitrate  of  iron  prepared  by  Prof.  Proc- 
ter's formula  at  the  same  time  that  the  preparations  of  the  sesqui- 
salt  were  made,  continue  unaltered  and  perfectly  good  up  to  this 
time. 
The  conclusions  then  to  be  drawn  from  these  facts  are,  that  the 
syrup  of  sesqui-nitrate  of  iron,  although  in  many  localities  an  oft 
prescribed  remedy,  is  an  unscientific  and  ineligible  preparation ; 
for,  without  an  excess  of  acid,  it  is  a  mixture  of  proto  and  per 
nitrate,  and  with  that  excess  the  acid  generates  oxalic  acid.  It  is  a 
superfluous  and  unnecessary  preparation,  for  as  the  simple  solution 
prepared  by  Prof.  Procter's  formula  keeps  perfectly  well,  there  can 
be  nothing  gained  by  adding  sugar  to  the  medicine,  the  dose  of 
which  is  so  small  that  it  cannot  sensibly  improve  the  flavor,  and 
as  the  iron  salt  is  already  per  oxidized  ;  sugar  is  of  no  use  for  pre- 
venting what  would  not  occur — the  further  absorption  of  oxygen 
from  the  atmosphere. 
When  a  syrup  of  nitrate  of  iron  is  wanted,  the  jorofo-nitrate 
should  be  employed ;  in  it  there  is  no  excess  of  acid  to  act  on  the 
sugar,  which  is  employed  to  prevent  peroxidation  of  the  iron,  and 
it  is  not  only  permanent  but  pleasant  to  the  palate. 
NOTE  ON  ADULTERATED  POWDERED  SOCOTRINE  ALOES. 
By  William  Procter,  Jr. 
Having  been  recently  called  upon  to  examine  two  specimens  of 
aloes  in  reference  to  their  purity,  it  has  been  thought  that  a  few 
remarks  relative  to  the  result  will  not  be  without  use* 
