Am.  Jour.  Pharm. 
Jan.,  1889. 
Analytical  Notes. 
9 
color,  which  changes  to  a  brown  in  one  or  two  hours.  Concentrated 
nitric  acid  dissolves  it  with  a  reddish-brown  color.  Concentrated  hy- 
drochloric acid  gives  an  orange  red  color. 
With  oxidizing  agents,  like  permanganate  of  potassium,  chromic 
acid  (K2Cr207+H2S04),  or  nitric  acid,  it  is  decomposed,  with  the  pro- 
duction of  a  strong  heliotropin-like  odor,  which  is  quite  characteristic, 
being  produced  even  in  very  dilute  solutions.  A  cold  solution  of 
methysticin  in  diluted  alcohol,  on  being  boiled  for  a  few  seconds  with 
dilute  nitric  acid,  gives  a  decided  odor  of  heliotrope.  This  does  not 
occur  with  other  oxidizing  agents  in  such  dilute  solutions. 
The  color,  with  concentrated  sulphuric  acid,  is  also  quite  character- 
istic, a  bright  carmine  red  being  produced,  in  rather  dilute  solutions,  on 
adding  to  four  or  five  drops  of  the  latter  about  ten  drops  of  the  acid. 
ANALYTICAL  NOTES. 
Abstracts  from  Theses. 
Gallic  acid. — Specimens  of  gallic  acid  from  different  manufacturers 
Avere  procured  by  Fred.  Win.  Meissner,  Jr.,  Ph.  G.,  and  subjected  to 
the  pharmacopceial  tests.  The  saturated  aqueous  solutions  yielded 
no  precipitates  with  an  alkaloidal  salt,  albumen  or  gelatinized  starch, 
but  produced  heavy  white  precipitates  with  a  solution  of  tartar  emetic 
and  ammonium  chloride.  Even  in  very  dilute  solutions  of  gallic 
acid  a  distinct  precipitate  was  obtained  by  this  test,  and  previous 
continued  washing  with  cold  water  did  not  prevent  the  precipitation. 
Gallic  acid  was  then  prepared  by  Liebig's  process  from  tannin  by 
boiling  with  sulphuric  acid,  recrystallizing  and  decolorizing  with  animal 
charcoal,  remaining  traces  of  tannin  being  removed  by  solution  of 
lead  acetate,  as  suggested  by  Watt.  The  crystals  thus  obtained 
answered  all  the  pharmacopoeial  requirements ;  the  result  may,  per- 
haps, have  been  caused  by  the  presence  of  a  slight  amount  of  acetic 
acid.  The  albumen  and  alkaloid  tests  are  regarded  as  sufficiently 
delicate  for  the  detection  of  tannin  in  gallic  acid,  one  part  in  thirty 
being  easily  indicated. 
Five  samples  of  gallic  acid  on  being  heated  to  100°  C.  lost  re- 
spectively 9*5,  9'6  9-75,  9*75  and  10*5  per  cent,  of  water. 
Granular  salts  of  caffeine. — William  Kuder,  Ph.  G.,  procured  a 
sample  of  crystallized  citrate  of  caffeine,  which  was  of  neutral  reac- 
tion, and  volatilized  completely  when  heated  on  platinum  foil.    A  so- 
