454 
EMPLOYMENT  OF  FERROCYANIDE  OF  POTASSIUM. 
avoided,  but  it  appears  rather  injurious  than  otherwise.  In  the 
most  successful  experiments,  the  formation  of  organized  beings 
took  place  in  the  lowest  possible  degree. 
These  details  show  how  complex  are  the  phenomena  of  fer- 
mentation, and  how  many  unknown  and  obscure  elements  they 
include ;  nevertheless,  chemists  may  set  in  action  the  forces 
which  cause  them,  and  direct  them  upon  definite  bodies,  and  to 
the  accomplishment  of  determinate  metamorphoses.  It  is  nearly 
in  the  same  way  that  they  set  in  action  the  ordinary  affinities, 
the  intimate  nature  of  which  is  scarcely  better  known.  The 
employment  of  ferments  is  only  distinguished  therefrom  by 
the  pre-existence  of  a  peculiar  and  extremely  mobile  form  and 
constitution,  produced  without  one  intervention,  under  the  influ- 
ence of  life. 
However  this  may  be,  the  preceding  experiments  are  dis- 
tinguished by  their  synthetic  character  from  the  fermentations 
hitherto  known.  Instead  of  changing  sugar,  mannite,  or  gly- 
cerine into  alcohol,  lactic  and  butyric  acids,  more  simple  com. 
pounds,  and  more  difficult  of  decomposition,  they  lead  to  the 
conversion  of  mannite  and  glycerine,  bodies  which  are  tolerably 
stable,  deprived  of  rotatory  power,  and  approaching  those  which 
we  know  how  to  produce,  into  a  substance  endowed  with  less 
stability  and  a  higher  order  of  complication,  in  fact,  into  a  true 
sugar,  analogous  to  those  formed  under  the  vital  influence  in 
the  interior  of  the  vegetable  and  animal  tissues. — London  Chem, 
Gfaz.  from  Comptes  Bendus,  May,  1857. 
ON  THE  EMPLOYMENT  OF  FERROCYANIDE   OF  POTASSIUM 
FOR  THE  REMOVAL  OF  RUST  SPOTS  UPON  WHITE  LINEN. 
By  Prof.  Runge. 
The  employment  of  ferrocyanide  of  potassium  may  often  help 
us  out  of  great  difficulties  in  the  case  of  rust  spots  upon  linen. 
These  do  not  always  consist  of  common  hydrated  oxide  of  iron, 
but  also  frequently  of  oleate  of  iron,  which  can  only  be  removed 
with  difficulty,  and  with  the  assistance  of  heat,  by  oxalic  acid, 
or  the  binoxalate  of  potash ;  and  often  not  at  all  by  sulphuric 
or  muriatic  acid,  for  these  acids  can  only  be  applied  cold  and 
