516 
JUICE  OF  SOLANUM  LYCOPERSICUM. 
a  warm  situation  for  three  days.  The  juice  was  then  strained  off, 
with  expression,  and  filtered. 
The  filtrate  was  of  a  wine  color,  clear  and  strongly  acid.  By 
boiling  it  was  coagulated.  By  a  second  filtration  the  coagulum 
was  separated,  but  it  amounted  to  so  little  that  I  was  obliged 
to  limit  myself  to  but  a  single  experiment.  I  heated  it,  after 
washing  and  drying,  in  a  glass  tube  closed  at  one  end,  and 
noted  the  appearance  of  alkaline  vapors,  smelling  like  heated 
horny  matter,  indicating  albumen. 
The  filtered  juice  reacted  as  follows,  viz. 
Ammonia  produced,  in  the  cold,  no  change  ;  on  boiling,  a 
white  pulverulent  precipitate. 
Solution  of  potassa— a  reddish  brown  color  ;  on  boiling,  a 
flocculent  precipitate. 
Nitrate  of  silver — a  dense  cloud ;  and  on  standing,  a  light 
precipitate,  which  did  not  entirely  dissolve  in  nitric  acid. 
Chloride  of  barium — gradually  a  precipitate  not  entirely  so- 
luble in  muriatic  acid. 
Chloride  of  calcium,  chloride  of  iron,  ferrocyanide  of  potas- 
sium, produced  no  change  in  the  juice. 
Oxalate  of  ammonia  threw  down  immediately  a  dense,  firm 
precipitate — this  being  filtered  off,  phosphate  of  ammonia 
caused  a  slight  precipitate. 
Tartaric  acid  produced  a  crystalline  deposit. 
Lime  water  occasioned  gradually  a  slight  turbidity  ;  on  boil- 
ing, a  white  flocculence  separated,  which  was  partly  soluble  in 
a  solution  of  sal  ammoniac.  The  portion  not  soluble  in  sal  am- 
moniac, dissolved,  after  washing,  in  dilute  nitric  acid,  in  which 
solution  molybdate  of  ammonia  produced  a  citron  yellow  precip- 
itate. 
After  lime  water  had  thus  thrown  down  a  white  flocculent 
precipitate  by  boiling,  the  mixture  was,  upon  cooling,  immedi- 
ately filtered,  and  the  filtrate  boiled.  No  turbidity  was  pro- 
duced,— the  solution  remaining  as  clear  as  water.  I  conclude 
from  this  that  no  citric  acid  is  contained  in  the  juice. 
Neutral  acetate  of  lead  caused  a  dense  white  precipitate  : 
this  was  partially  dissolved  in  acetic  acid.  Boiled  with  water 
and  filtered  while  hot,  the  filtrate  deposited,  on  further  dilution 
with  water  and  cooling,  a  small  amount  of  a  crystalline  powder. 
