FACTS  AND  THEORIES  OF  FERMENTATION.  463 
the  liquid  was  but  little  changed,  having  merely  a  musty  smell ; 
no  mould  was  perceptible.  The  flask  was  now  agitated,  to  expel 
the  air  contained  therein  and  replace  it  with  fresh  air ;  the  next 
day  it  was  found  covered  with  a  thick  growth  of  PenicilHum 
glaucum,  was  strongly  acid,  had  a  putrid  odor,  and  underwent 
rapid  putrefaction. 
On  the  23d  of  November,  one  week  previous  to  the  above 
mentioned  experiments,  a  portion  of  wort  was  placed  in  the  ap- 
paratus, arranged  as  just  described,  the  conditions  being  exactly 
the  same  as  in  the  last  experiment,  excepting  that  the  sugar  was 
not  heated  previously  to  being  placed  in  the  filter  tube.  On  the 
fourth  day  of  the  operation  fermentation  commenced,  alike  in 
the  beaker  glass  and  in  the  experimental  flask  a  ;  a  thick  forma- 
tion of  mould  covered  the  liquid  ;  the  process  was  then  interrupt- 
ed and  commenced  anew  as  previously  described. 
This  result  clearly  indicates  that  there  is  contained  in  the  su- 
gar, as  met  with  in  commerce,  a  substance  capable  of  being  taken 
up  by  a  current  of  air  passing  over  or  through  it,  and  pos- 
sessing the  property,  while  thus  suspended  or  dissolved  in  the  air, 
of  producing  fermentation  and  the  growth  of  mould  in  fresh  wort; 
this  property,  however,  being  destroyed  by  a  temperature  of  212° 
F.  The  author  believes  that  sugar  possesses  this  property  in 
common  with  all  matter,  organic  and  inorganic,  that  is  not  de- 
structive to  vitality.  The  action  of  cotton  is  due,  therefore, 
simply  to  its  finely  divided  condition,  and  not  to  any  peculiarity 
in  form  or  composition.  The  germs  floating  in  the  air  being  de- 
posited or  taken  up  again,  precisely  as  finely-divided  dust  would 
be  under  the  same  conditions. 
It  is  not  probable  that  the  globules  found  in  the  washing  water 
are  the  germs  of  the  plants  causing  fermentation,  etc.  It  is 
more  likely  that  they  are  the  partially-developed  globules,  having 
a  magnitude  many  times  greater  than  the  actual  germ  that  is 
suspended  in  the  air  and  distributed  through  all  nature.  The 
cryptogamia  found  in  their  full  development,  and  the  innumera- 
ble globules  present,  had  doubtless  been  nourished  and  attained 
their  present  size  by  the  volatile  matters  given  off  by  the  fer- 
menting liquids  in  the  beaker  glass  i,  and  a  portion  of  which 
must  have  been  absorbed  in  their  passage  through  the  water. 
The  true  original  germs  are  without  doubt  contained  in  the  su- 
