ON  CORYDALIS  FORMOSA.  209 
such  giving  negative  indications,  in  order  to  avoid  minutiae.  To 
give  a  summary  view  of  the  last  subject,  setting  forth  its  proper- 
ties and  behaviour  towards  chemical  tests,  individually  and  in 
relation  to  other  known  organic  acids  for  the  purpose  of  estab- 
lishing its  identity,  the  following  will  perhaps  prove  how  far  the 
results  may  bo  from  being  correct : 
Malic  Acid  is  precipitated  by  barjtic  water,  while  fumaric  acid  is  no'.  A 
neutral  alkaline  raalate  forms  a  precipitate  with  nitrate  of  silver,  which  changes 
after  a  time  into  colorless  transparant  crystals.  Fumaric  acid  forms,  under  similar 
circumstances,  a  white  precipitate  which  does  not  change. 
Malic  Acid  resembles  fumaric  in  the  behaviour  of  alkaline  fumarates  towards 
chloride  of  calcium,  both  heated  on  mixing  to  ebullition.  But  differs  from  it  in 
its  compound  of  oxide  of  lead,  which,  in  the  former,  melts  in  hot  water,  forming  a 
mass  of  a  pitchy  consistence;  while  the  latter  does  not  change  or  melt.  Again> 
the  fumarate  of  copper  is  insoluble,  while  the  malate  crystallizes. 
Citric  acid.  An  alkaline  citrate  is  immediately  precipitated  in  the  cold  by 
chloride  of  barium  and  calcium,  while  an  alkaline  fumarate  gives  no  precipitate 
with  the  same  reagent  under  similar  circumstances. 
Tartaric,  racemic  and  oxalic  acids  resemble  fumaric  in  its  behaviour  toward 
solution  of  gypsum,  but  differ  from  fumaric  acid  in  their  action  upon  lime 
water. 
Succinic  acid  differs  from  fumaric  acid  by  its  salt  of  protoxide  of  manganese, 
which  crystallizes,  while  the  fumarate  is  insoluble.  In  its  salt  of  zinc,  which  is 
very  insoluble  while  the  fumarate  crystallizes.  It  resembles  fumaric  acid  by  an 
alkaline  succinate  producing  an  insoluble  precipitate  with  persalts  of  iron,  some- 
what similar  to  that  obtained  by  an  alkaline  fumarate. 
Formic  acid  differs  from  fumaric  by  its  behaviour  towards  persalts  of  mercury 
and  silver  which  are  reduced. 
Acetic  acid  differs  from  fumaric  acid  by  its  salts  of  protoxide  of  copper  and 
manganese,  which  are  very  soluble. 
VII.  Determination  of  inorganic  constituents.  The  remain- 
ing liquid  after  the  precipitation  of  the  organic  acid,  and  the 
solution  deprived  of  its  excess  of  lead  by  hydro-sulphuric  acid 
gas  was  concentrated  and  filtered.  The  solution  gave  with 
tartaric  acid  in  excess,  a  precipitate  of  bi-tartrate  of  potassa. 
Oxalate  of  ammonia,  the  white  pulverulent  precipitate  of  oxalate 
of  lime.  The  powdered  root,  after  exhaustion  with  dilute  alcohol 
on  incineration,  gave  a  considerable  amount  of  ashes,  which 
effervesced  strongly  on  dissolving  in  hydrochloric  acid.  Evapo- 
rated to  dryness  and  dissolved  in  distilled  water,  the  filtered  solu- 
tion gave,  with  oxalate  of  ammonia,  a  precipitate  of  oxalate  of 
lime  ;  by  the  addition  of  ammonia,  the  gelatinous  hydrate  of 
alumina :  with  ferrocyanide  of  potassium,  a  blue  precipitate.  A 
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