FACTS  AND  THEORIES  OF  FERMENTATION.  459 
above  the  lower  cork  ;  through  the  upper  cork  was  inserted  the 
bent  limb  of  the  drying  tube  d,  containing  fragments  of  dried 
chloride  of  calcium,  the  other  end  of  the  drying  tube,  connected 
with  the  nitrogen  bulb  or  washing  apparatus  e,  containing  about 
J  ounce  of  water  ;  from  this  a  tube  passed  to  the  bell  glass  /, 
through  the  cork  at  top,  through  which  also  passed  another 
straight  tube  k,  reaching  to  the  centre  of  the  bell  glass,  for  the 
purpose  of  admitting  air.  The  bell  glass  was  closed  at  the  bottom 
by  a  plate  of  ground  glass  g,  supported  upon  a  sliding  support  h, 
kept  at  any  desired  elevation  by  a  set  screw  ;  within  the  bell 
glass  was  placed  a  beaker  glass  i,  resting  upon  the  glass  plate  g9 
so  that  it  could  be  removed  at  pleasure.  Into  this  beaker  glass 
was  poured  an  infusion  of  malt,  (wort,)  similar  to  that  in  the 
flask  a.  The  tin  cannister  6,  was  provided  with  an  opening 
through  which  it  could  be  filled,  and  capable  of  being  closed  air 
tight ;  at  the  bottom  was  a  discharge  cock  Z,  leading  into  a  situa- 
ble  receiver.  It  is  evident  that,  if  the  joints  of  the  apparatus 
are  all  closed  air  tight,  (the  cannister  being  filled  with  water,) 
and  the  cock  I  opened  to  permit  the  escape  of  the  water,  a  cur- 
rent of  air  must  enter  through  the  tube  Jc,  into  the  bell  glass  /, 
and  from  thence  pass  through  the  washing  tube  e,  the  drying 
tube  d,  the  filter  tube  e,  and  the  flask  a,  containing  the  experi- 
mental liquid,  and  finally  into  the  cannister  b,  supplying  the  void 
created  by  the  escape  of  the  water.    The  substance  selected  for 
the  filtering  medium  was  pure  white  sugar,  in  grains  of  the  size 
