"^"nov^882^'^°'*}  Constitution  of  Albumenoids.  579 
instruments  of  life — may  be  considered  possible  and  even  probable,  as 
well  as  the  precise  definition  of  their  specific  constituents. 
Although  these  matters  do  not  crystallize  or  volatilize  or  form  well- 
defined  combinations  with  bases  or  acids,  they  possess  one  character 
which  is  constant  and  distinctive,  and  that  is  the  action  that  bodies  of 
this  nature  exercise  upon  the  plane  of  polarized  light.  In  studying 
various  albumenoid  matters  under  this  aspect  M.  Bechamp  has  suc- 
ceeded in  separating  them  into  species  which,  if  not  absolutely  defined 
and  comparable  to  those  represented  by  volatile  or  crystallizable  sub- 
stances, at  least  present  the  results  of  the  first  serious  attempt  towards 
a  regular  classification  of  these  interesting  products. 
In  order  to  appreciate  the  importance  of  this  inquiry  it  is  sufficient 
to  recall  the  fact  that  the  organs  of  all  animals  and  the  liquids  bathing 
them  are  formed  of  or  contain  such  matters,  and  that  if  they  do  not 
constitute  the  preponderating  materials  in  the  tissues  and  juices  of 
plants,  their  presence  in  them  does  not  seem  to  be  less  general  or  less 
essential,  especially  at  the  commencement  of  cell  formation.  If  it  be 
added  that  analyses  of  these  substances  and  their  interpretation  have 
led  chemists  to  admit  that  their  molecule  contains  not  less  than  from 
five  to  six  hundred  atoms  of  carbon,  hydrogen,  oxygen,  or  nitrogen,  it 
will  be  unde^tood  what  a  distance  separates  these  bodies  from  those 
much  less  complex  ones,  the  study  of  which  has  served  as  a  founda- 
tion for  the  doctrines  upon  which  systematic  organic  chemistry  rests. 
The  first  question  to  resolve  in  connection  with  this  group  of  bodies 
consists  in  breaking  up  the  mixtures  in  which  they  occur  in  nature 
nnd  isolating  those  individuals  possessing  fixed  and  sufficiently  funda- 
mental properties  to  warrant  their  being  considered  specific  and  essen- 
tial. 
White  of  egg  contains  at  least  three  bodies :  one  precipitable  by  sub- 
acetate  of  lead ;  a  second  by  ammoniacal  subacetate  of  lead ;  and  a 
third  which  is  not  coagulable  by  heat,  and  is  soluble  in  water  and 
insoluble  in  alcohol,  by  which  means  it  is  separable  from  an  aqueous 
solution.  The  first  two  of  these  substances  present  the  general  char- 
acter of  albuminoid  matters;  the  third  belongs  to  the  class  of  ferments 
and  liquefies  starch. 
The  ferment  discovered  in  the  white  of  egg  by  M.  Bechamp  explains 
some  of  the  phenomena  which  occur  during  incubation.  Its  presence 
there  caused  him  to  look  for  it  in  other  albuminoid  products,  and  a 
general  idea  of  his  work  may  be  given  by  saying  that  he  has  sue- 
