554  TANNIC  ACID  IN  PLANTS. 
soluble  in  excess  of  sulphuric  acid,  sparingly  soluble  in  alcohol 
and  in  ether.  The  hydrochlorate  is  copiously  soluble,  crystal- 
lizes in  large  clear  prisms  of  a  very  bitter  taste. 
The  double  salt  with  chloride  of  platinum  is  a  pale  yellow  crys- 
talline powder,  sparingly  soluble  in  hot  water,  alcohol,  or  ether, 
but  more  soluble  in  excess  of  chloride  of  platinum,  from  which 
solution  it  may  be  obtained  in  well-developed  crystals. 
The  soluble  salts  of  this  base  give  with  caustic  and  carbonated 
alkalies,  white  precipitates ;  with  infusion  of  galls,  a  white  pre- 
cipitate ;  with  chloride  of  gold,  a  yellow  precipitate  ;  with  per- 
chloride  of  iron,  potassio-tartrate  of  antimony,  sulphate  of  cop- 
per, iodide  of  potassium,  and  oxalate  of  potash,  they  do  not  give 
precipitates.  Chloride  of  mercury  forms  with  it  a  white  insoluble 
double  salt. 
The  analysis  of  this  base  and  of  its  hydrochlorate  and  the  dou- 
ble salt  with  chloride  of  platinum  gave  the  following  results  for 
100  parts  : — 
Calculated. 
C.  77.54      77.68         —    77.92 
H.    7.73        7.76      7.71    7.79 
N.    8.81         —         —    9.09 
0.     —  —         —    5.15 
100.00 
The  hydrochlorate  gave  19.30  per  cent,  of  chlorine,  and  the 
platinum  compound  27.81  and  27.80  per  cent,  platinum. 
These  members  agree  with  the  formula  C20  H12  NO,  which  re- 
quires 18.63  per  cent,  chlorine,  and  27.50  platinum.  This  base 
is  therefore  isomeric  with  quinine. 
The  therapeutic  value  of  the  hydrochlorate  of  this  base  has 
been  tried  by  Drs.  Homeier  and  Schmidt,  both  of  whom  consider 
that  it  is  an  efficient  remedy  for  intermittent  fever. 
OCCURRENCE  OF  TANNIC  ACID  IN  PLANTS. 
By  B.  H.  Paul,  Ph.  D. 
It  has  been  thought  that  tannic  acid  is  not  one  of  the  earliest 
products  of  assimilation  in  the  plant  organism,  but  rather  among 
the  number  of  substances  which  are  not  included  within  the  circle 
of  vital  action  ;  that  it  is  a  product  of  the  oxidation  of  cells  that 
have  lost  vitality.  Dr.  Karsten  has  been  led  to  question  the  cor- 
