.018 
JUICE  OF  SOLANUM  LYCOPERSICUM. 
a  yellow  color,  and  clear  acid  taste.  Sugar  of  lead  caused  a 
yellow  flocculent  precipitate  in  it,  which  collected  together  upon 
heating  ;  and  was  entirely  soluble  in  acetic  acid.  Chloride  of 
zinc  produced  no  alteration  in  the  cold  ;  upon  heating,  a  floccu- 
lent turbidity. 
The  residue  of  the  extract  was  now  treated  with  alcohol, 
which,  however,  left  a  considerable  portion  undissolved. 
The  alcoholic  solution,  slowly  evaporated  to  dryness,  yielded 
a  mass  which,  with  the  exception  of  a  very  minute  quantity  of 
resin,  was  soluble  in  hot  water.  After  cooling  and  filtering,  the 
liquid  possessed  a  reddish  brown  color,  was  clear,  and  had  a 
sweetish  acid  taste. 
A  solution  of  sulphate  of  copper  mixed  with  tartaric  acid 
produced  in  the  filtrate  previously  rendered  alkaline,  when 
warmed,  a  considerable  yellowish  red  precipitate. 
A  portion  of  the  filtrate  was  mixed  with  a  few  drops  of 
chloride  of  iron,  heated  nearly  to  boiling,  liquor  potassa  added, 
boiled  and  again  filtered.  In  this  filtrate  the  presence  of  iron 
was  indicated  by  a  black  precipitate  with  sulphuretted  hydrogen. 
From  this  I  infer  the  presence  of  tartaric  acid  ;  there  had 
been  formed  the  tartrate  of  iron  and  potassa,  which  remained 
in  solution  by  the  presence  of  free  alkali,  and  yielded  its  iron 
only  upon  the  addition  of  sulphuretted  hydrogen.  At  least 
neither  malic  nor  citric  acid  would  have  afforded  an  alkaline  so- 
lution containing  iron  under  these  circumstances. 
Another  portion  of  the  aqueous  solution  of  the  alcoholic  ex- 
tract, mixed  with  sugar  of  lead,  gave  a  flocculent  precipitate, 
which  collected  upon  heating,  and  dissolved  with  but  a  very 
small  residue  in  acetic  acid.  The  remainder  of  the  aqueous  so- 
lution of  the  alcoholic  extract  was  evaporated  to  the  consistence 
of  an  extract,  and  heated  in  a  test  tube  with  a  few  drops  of  sul- 
phuric acid— frothing  was  produced,  and  the  disengagement  of 
pungent  acid  vapors  of  malic  acid — which  crystallized  upon  the 
cooler  part  of  the  tube. 
The  portion  of  the  ethereal  extract  insoluble  in  alcohol  dis- 
solved completely  in  water,  forming  a  clear  reddish  brown  solu- 
tion. This  solution  was  insipid  to  the  taste,  somewhat  salty, 
neither  bitter  nor  astringent.  Chloride  of  iron  produced  in  it 
no  change. 
