PARAFFIN  AND  PURE  ACETIC  ACID. 
235 
There  is  apparently  no  doubt  that  the  presence  of  caustic  pot- 
ash facilitates  the  conversion  of  cyanide  of  potassium  into  ferro- 
cyanide. — London  Pharm.  Journ.,  March,  1854. 
PREPARATION  OF  PARAFFIN  AND  PURE  ACETIC  ACID  UPON 
A  LARGE  SCALE  FROM  THE  DISTILLATION  PRODUCTS  OF 
WOOD. 
By  Reinhold  V.  Reichenbach. 
The  author  having  had  occasion  to  prepare  a  large  quantity  of 
pure  paraffin,  was  desirous  of  adopting  some  less  tedious  process 
than  that  by  which  his  father  obtained  this  substance  in  the  first 
instance.  Under  these  circumstances  he  was  induced  to  try  the 
action  of  sulphuric  acid  at  a  high  temperature,  supposing  that  it 
would  then  be  more  efficacious  in  destroying  the  empyreumatic 
substance  mixed  with  the  paraffin.  For  this  purpose  he  half-filled 
a  large  glass  retort  with  fuming  sulphuric  acid,  and  added  one- 
third  its  weight  of  well  pressed  raw  paraffin.  The  temperature 
was  gradually  raised  in  a  sand  bath  until  distillation  began,  and 
after  a  tinie  he  found  that  the  whole  of  the  paraffin  had  passed 
over  and  presented  an  appearance  of  perfect  whiteness  and  purity. 
From  the  success  of  this  operation,  he  applied  the  method  to 
the  preparation  of  pure  acetic  acid.  The  substance  employed 
was  the  ordinary  raw  acetate  of  soda.  This  salt,  containing  a 
large  quantity  of  empyreumatic  resin,  yielded,  when  distilled 
with  concentrated  sulphuric  acid,  about  half  its  quantity  of  very 
strong  acetic  acid,  which  was  clear,  perfectly  colorless,  and  free 
from  any  empyreumatic  odour.  It  was  not  until  the  temperature 
was  ra^ed,  in  order  to  continue  the  distillation,  that  the  distil- 
late began  to  present  a  brownish-yellow  color,  and  at  the  same 
time  a  peculiar  turbidity.  Both  these  circumstances  appeared 
to  be  owing  to  some  other  cause  than  the  presence  of  empyreu- 
matic admixtures,  and  they  were  found  to  result  from  a  decom- 
position of  sulphuric  acid,  by  the  carbonaceous  matter  in  the  re- 
tort, and  a  consequent  distillation  of  sulphur  with  the  acetic  acid. 
The  turbid  and  somewhat  colored  acid  was  rendered  perfectly 
pure  by  redistillation. 
The  author  then  endeavored  to  conduct  the  distillation  in  such 
a  manner  as  to  prevent  this  inconvenience.  The  layer  of  acetate 
and  sulphuric  acid  next  to  the  heated  wall  of  the  retort  would 
