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SULPHATE  OF  MANGANESE. 
I  used  nitric  acid  in  the  quantity  mentioned  in  the  formula,  but 
of  deficient  strength.  Since  then  I  have  been  very  particular 
to  continue  the  heat,  and  if  necessary  add  a  small  extra  quantity 
of  acid  nitric,  (to  be  subsequently  driven  off  by  heat)  until  the 
solution  tested  with  ferrid-cyanide  of  potassium  fails  to  produce 
the  characteristic  blue,  showing  the  presence  of  protoxide  of 
iron. 
I  am  of  the  opinion  that  the  U.  S.  Formula  will  always  pro- 
duce a  good  article  of  pyrophosphate  of  iron,  when  proper  atten- 
tion is  given  to  details. 
Hoping  these  suggestions  may  prove  of  some  service,  I  remain 
yours  respectfully,  Kobt.  W.  Gardner. 
Bergen,  N.  J.,  April  Qth,  1869. 
SULPHATE  OF  MANGANESE. 
By  Dr.  0.  J.  Rademaker. 
To  the  Editor  of  the  Journal  of  Pharmacy. 
Having  occasion  to  prepare  some  sulphate  of  manganese, 
several  formulas  where  resorted  to,  as  heating  binoxide  of  man- 
ganese with  sulphuric  acid,  heating  carbon  sulphuric  acid  and 
binoxide  of  manganese,  and  Mr.  Lester's  process  of  hydro- 
chloric acid  and  binoxide  of  manganese,  and  boiling  the  result- 
ing solution  with  pure  carbonate  of  manganese,  all  of  which 
gave  very  impure  products,  with  the  exception  that  the  solution 
was  free  from  iron,  but  still  contained  copper,  cobalt  and  nickle. 
In  order  to  prepare  a  pure  salt  the  sulphate  was  decomposed 
with  carbonate  of  soda,  the  carbonate  of  manganese  redissolved 
in  ac^ic  acid,  the  solution  of  acetate  treated  with  sulphuretted 
hydrogen  ;  the  solution  filtered  and  decomposed  with  carbonate 
of  soda,  the  resulting  carbonate  of  manganese  redissolved  in 
pure  sulphuric  acid.  The  above  process  gave  a  perfectly  pure 
salt.  If  copper  only  is  present  it  is  not  necessary  to  convert  the 
manganese  into  acetate,  as  copper  is  precipitated  from  sulphate. 
Respectfully,  C.  J.  Rademaker,  M.  D. 
Louisville,  April  5,  1869. 
