314 
ON  THE  HYPOPHOSPHITES  OP  IKON. 
mortar  and  filter.  The  result  was,  the  commencement  of  a  cloudiness  after 
two  or  three  hours,  and  a  considerable  precipitate  after  standing  for  about 
24  hours.  I  determined  to  examine  the  nature  of  this  precipitate,  and 
accordingly  it  was  well  washed  with  cold  water  and  dissolved  in  muriatic- 
acid,  which  took  it  up  without  leaving  any  residue,  and  resulting  in  a  per- 
fectly clear  solution  with  a  decidedly  brownish  yellow  coloration.  To  a  part 
of  this  solution  was  added  sulphuric  acid,  and  afterwards,  ammonia  nearly 
to  neutralization ;  a  further  addition  of  sulphuric  acid  caused  no  precipita- 
tion. The  solution,  treated  in  the  same  way  with  oxalic  acid,  was  likewise 
not  precipitated.    These  tests  prove  the  absence  of  lime. 
The  solution  was  over-saturated  with  ammonia,  which  caused  a  brown 
precipitate.  Ferrocyanuret  of  potassium  immediately  threw  down  a  precipi- 
tate of  Prussian  blue,  thus  proving  the  presence  of  sesquioxide  of  iron. 
The  precipitate  from  the  syrup  was  insoluble  in  hypophosphorous  acid  ; 
to  ascertain  the  acid,  which  was  combined  with  the  oxide  of  iron,  I  dissolved 
another  portion  in  muriatic  acid,  supersaturated  the  solution  by  ammonia, 
filtered,  acidulated  with  muriatic  acid,  added  a  drop  of  solution  of  sesqui- 
chloride  of  iron,  and  afterwards  an  excess  of  acetate  of  potassa.  A  white 
gelatinous  precipitate  of  phosphate  of  sesquioxide  of  iron  was  the  result. 
The  filtered  solution  containing  an  excess  of  free  ammonia  was  mixed 
with  sulphate  of  magnesia ;  a  white  precipitate  of  phosphate  of  ammonia 
and  magnesia  resulted,  insoluble  in  ammonia,  but  soluble  in  acetic  acid. 
By  these  reactions  the  presence  of  phosphoric  acid  is  proven. 
The  same  solution,  neutralized  with  hydrochloric  acid,  caused  white  pre- 
cipitates with  nitrate  of  silver  and  chloride  of  mercury,  (corrosive  subli- 
mate). After  boiling,  the  color  of  both  precipitates  was  unchanged,  and 
no  silver  or  mercury  could  be  detected,  even  by  a  magnifying  glass.  This 
indicates  the  absence  of  phosphorous  acid,  and  the  precipitate  from  the 
syrup  was  phosphate  of  sesquioxide  of  iron. 
Berzelius,  in  his  "  Lehrbuch,"  says  of  the  hypophosphite  of  sesquioxide 
of  iron:  «« It  is  white  and  little  soluble  in  an  excess  of  the  acid.  At  ordinary 
temperature  the  oxide  is  not  reduced  to  the  protoxide  ;  but  on  boiling  the 
mixture,  hypophosphite  of  protoxide  of  iron  is  dissolved,  leaving  basic 
phosphate  of  sesquioxide  behind." 
Would  it,  in  consonance  with  these  facts,  not  be  better  to  treat  the  hypo- 
phosphites  with  water  at  an  ordinary  temperature,  and  perhaps  reduce  the 
amount  of  the  iron  salt  to  the  quantity  which  then  may  be  taken  up  by  the 
hypophosphorous  acid? 
I  remain  yours,  very  respectfully,  J.  M.  Maisch. 
The  suggestion  in  the  last  paragraph  had  also  been  attended 
to,  as  I  found  the  employment  of  very  hot  water  to  effect  the 
character  of  the  solution  of  the  salts,  unless  a  decided  excess  of 
acid  was  present. 
