542 
EXAMINATION  OF  KINO. 
alcohol.  But  neither  boiling  water  or  alcohol  dissolve  kino  com 
pletely,  a  more  or  less  swollen  skeleton  of  each  individual  frag 
merit  always  remaining.  The  addition  of  distilled  water  to  the 
tincture  causes  a  faint  cloudiness,  which  disappears  again  sponta- 
neously. Ether  produces  a  precipitate  in  both  aqueous  and  alco- 
holic extracts,  but  both  become  clear  on  standing.  When  the 
tincture,  containing  ether,  is  evaporated,  it  becomes  turbid  at 
the  boiling  point,  from  the  separation  of  cinnamon-colored  flocks, 
which  subsequently  redissolve  with  violent  agitation  of  the  li- 
quid. Ether  does  not  take  up  anything  even  from  finely-powdered 
kino. 
Tincture  of  kino  reddens  litmus  somewhat  more  distinctly  than 
the  aqueous  infusion.  The  former  is  precipitated  by  alkalies  ;  the 
latter  only  by  carbonate  of  ammonia  ;  neither  give  any  precipitate 
with  lime  water  or  tartrate  of  potash  and  antimony.  Protocblo- 
ride  of  iron  gives  with  the  aqueous  infusion  a  deep  green  color, 
and  green  flocks  separate  after  some  time.  Percholoride  of  iron 
gives  a  greyish  or  yellowish-green  bulky  precipitate ;  lead  salts 
give  various  precipitates  according  as  the  infusion  is  prepared  with 
hot  water  or  cold,  wThen  air  has  access  or  the  contrary. 
African  kino  burnt  in  a  porcelain  crucible  leaves  about  two  per 
cent,  of  ash,  consisting  of  phosphate  of  soda,  carbonate  of  lime, 
and  silicate  of  iron.  When  submitted  to  dry  distillation  it  gives 
off  an  odor  resembling  vanilla,  acid  water  then  passes  over  (per- 
haps formic  acid)  and  some  empyreumatic  substances  not  exam- 
ined ;  pyrogallic  acid  could  not  be  detected.  Heated  upon  platinum 
foil  it  swells  up,  evolving  first  agreeable  and  then  acid  vapors. 
As  the  author  could  not  succeed  in  affecting  a  simple  separation 
of  the  astringent  principle  of  kino,  the  behavior  of  various  rea- 
gents with  aqueous  and  alcoholic  infusions  was  more  carefully  ex- 
amined. The  separation  of  the  tannic  acid  by  means  of  a  solution 
of  gelatine  recommended  by  Gerding,  is  imperfect;  but  if,  on  the 
other  hand,  a  prepared  animal  skin  is  employed,  only  a  little  gal- 
lic acid  is  left  in  the  liquid,  inasmuch  as  the  red  coloring  matter 
enters  into  combination  together  with  the  tannic  acid,  forming  a 
red  leather.  The  contact  of  oxygen  with  Gerding's  coccotannic 
acid,  gave  a  different  result ;  a  stream  of  oxygen  passed  through 
the  aqueous  infusion  of  kino  does  not  cause  any  perceptible  altera- 
tion of  the  tannin  even  after  long  warming,  the  coloring  matter 
