'*''"'Apiii'"i885^'"''}  ^"^^  Liquor-  Calcis  Saccharratus.  181 
freshly  made  liq.  calcis  sacch.,  and  after  standing  for  twelve  hours,  the 
solution  was  found  to  be  more  highly  colored  than  a  sample  of  liquor 
which  had  been  made  for  eighteen  months  and  kej)t  under  conditions 
favorable  to  the  development  of  color.  In  a  similar  experiment  with 
pure  grape  sugar,  the  liquor,  also  acquired  in  a  short  time  a  distinct 
yellow  color,  but  not  nearly  to  the  same  extent  as  with  impure  grape 
sugar.  The  next  point  to  be  determined  was  an  explanation  of  the 
relationship  between  exposure  to  air  and  the  development  of  color  in 
accordance  with  the  grape  sugar  theory.  It  was  found  that  after  boil- 
ing and  filtration  the  clear  liquid  from  which  the  lime  had  been  pre- 
cipitated by  CO2  still  contained  some  lime  in  solution  which  could  not 
be  precipitated  by  CO2,  and  was  apparently  combined  with  an  organic 
acid.  This  acid  might  be  readily  isolated  by  acidifying  with  II2SO4 
and  distilling,  but  time  would  not  allow  of  this  being  done,  and  con- 
sequently my  statements  in  regard  to  it  are  mainly  speculative  and 
suggestive. 
The  fact  that  contact  with  the  air  is  necessary  fo)  the  development 
of  color,  in  the  liquor  points  to  the  conclusion  that  it  is  due  to  some 
process  of  oxidation.  It  seems  probable  that  grape  sugar  and  an 
organic  acid  are  produced,  and  I  find  that  one  molecule  of  cane  sugar 
and  three  atoms  of  oxygen  give  one  molecule  of  grape  sugar  and  one 
molecule  of  saccharic  acid,  according  to  the  following  equation — 
C12IT22O11  -f-  O3— CgHi206 + CgHjyOg. 
Then  grape  sugar,  in  contact  with  solution  of  lime,  has  been  found  to 
be  gradually  changed  into  glucic  acid.  By  absorption  of  oxygen  from 
the  atmosphere  glucic  acid  becomes  transformed  into  aploglucic  acid, 
which  is  an  amorphous  substance  having  a  deep  brown  color,  and  this 
may  be  the  cause  of  the  coloration. 
I  have  observed  that  the  deposit  found  in  liq.  calcis  sacch.  which  has 
stood  for  some  time  does  not  effervesce,  or  only  very  slightly  on  the 
addition  of  hydrochloric  acid.  This  fact  may  be  explained  by  the 
theory  that  the  cane  sugar  is  tranformed  in  the  usual  way  into  grape 
sugar  and  levulose.  Levulose  is  known  to  form  an  insoluble  lime 
compound,  which  may  constitute  the  deposit  in  question,  the  subse- 
quent decomposition  of  the  grape  sugar  by  the  lime  producing  the 
color.  Formic  acid  is  known  to  be  produced  in  solutions  of  sugar  in 
contact  with  air  and  the  addition  of  ferric  chloride  to  the  clear  liquid 
from  which  the  lime  had  been  precipitated  certainly  gave  the  red 
