As  Bcid  of  the  above  strength  is  rarely  re-
quired, and  Rs  the  distillation  is  more  easily
conducted  when  the  ingredients  are  less  con-
centrated, a  little  water  may  be  conveniently
added  cither  before  or  towards  the  end  of  the
distillation.  Hence  the  following  proportions
have  been  recommended  : —

2.  (Volckel.)  Acetate  of  lime  (as  last),  100
parts;  hydrochloric  acid  (sp.  gr.  l'I6),  90  to
95  parts ;  water,  25  parts ;  mix,  and  proceed
as  before.  Prod.  96  to  98  parts  of  an  excel-
lent acid,  well  adapted  to  trading  purposes,
having  a  sp.  gr.  about  I'OSO,  and  containing
nearly  40 J  of  hydrated  acetic  acid.  It  has
been  correctly  remarked,  that  the  acetic  acid


produced  with  hydrochloric  acid  is  ah.ays  of
better  quality  than  that  produced  with  sul.
phuric  acid  ;  being  not  only  less  coloured,  but
also  entirely  free  from  sulphurous  acid.  The
distillation  uniformly  proceeds  with  ease  and
regularity,  and  the  whole  of  the  acetic  acid
passes  over  between  212°  and  248°  Fahr. ;  by
which  the  danger  of  contamination  with  other
products,  resulting  from  a  high  degree  of  heat,
is  obviated.
3.  An  Acetic  acid  sufficiently  strong  and
pure  for  many  ordinary  purposes  may  be  ob-
tained without  distillation,  by  pouring  strong
sulphuric  acid,  60  parts,  diluted  with  water,
5  parts,  on  well-dried  acetate  of  lime,  100
parts  J  digesting,  with  occasional  agitation  in
a  close  vessel,  decanting  the  clear  liquid,  and
straining  the  remainder.
A,  Fumnce.
B  B  B  B,  Glass  receivers.
C,  Stoneware  retort.
D,  Bottle  contaiiiini^  vinegar.
B E  BE,  Basins  Gontaining  water.
I'FFF,  Supports  for  basins.
