Am.  Jour.  Pharm. 
June,  la96. 
Tannins  of  Some  Ericacece. 
317 
oak  bark  tannin.  A  further  investigation  of  the  chemical  natures  of 
the  tannins  through  their  decomposition  products  was  then  decided 
upon,  so  for  this  purpose  the  effects  of  several  methods  of  decom- 
position were  tried.  These  methods  included  fusion  of  the  tan- 
nins with  caustic  alkali,  boiling  with  hydrochloric  acid,  and  the  ap- 
plication of  sufficient  heat  to  alter  their  chemical  constitutions  ;  they 
were  conducted  as  follows  : 
Fusion  with  Caustic  Alkali. — Some  of  the  tannin  was  added  to 
potassium  hydrate,  which  had  been  liquefied  by  heat.  The  mixture 
was  thoroughly  stirred  and  the  heat  continued  for  twenty  minutes, 
after  which  time  the  fusing  substances  were  allowed  to  become  cold. 
The  solid  cold  mass  was  dissolved  in  water,  the  resulting  solution 
slightly  acidified  with  dilute  sulphuric  acid,  the  unfiltered  mixture 
shaken  with  ether  and  the  solvent  separated  and  allowed  to  evapo- 
rate spontaneously.  Residues  of  a  more  or  less  reddish-brown 
color  were  obtained  in  all  cases.  These  residues  were  dissolved  in 
water  and  tested  qualitatively,  as  indicated  by  the  following  chart : 
Potassium 
Cyanide. 
Ferric  Chloride  and 
Sodium  Carbonate. 
Ferrous 
Sulphate. 
Lead  Acetate. 
Pine  Wood 
and  Hydro- 
chloric" Acid. 
Chimaphila  .... 
No  change. 
/Red  color,  reddish 
\    yellow  ppt. 
(Reddish ) 
X    color.  j 
Yellowish  ppt. 
No  change. 
Trailing  arbutus  .  . 
No  change. 
Green  ppt.,  red  color. 
Green  color. 
Yellowish  ppt. 
No  change. 
Gaultheria  
f  Olive  green  j 
\    color.  j 
Green  ppt. ,  red  color. 
Green  color. 
Brownish  ppt. 
Red  color. 
Mountain  laurel  .  . 
j  Olive  green  ) 
I    color.  j 
Green  ppt.,  red  color. 
Green  color. 
(  Brownish-  ) 
<      yellow  > 
I  PPt.j 
Red  color. 
Manzanita  .... 
No  change. 
(  No  change,  reddish- 
\    yellow  color. 
r  slight  | 
(         color,  j 
Yellowish  ppt. 
No  change. 
Uva  Ursi  
("Reddish 
[  color. 
/Green    ppt.,  red-") 
\    dish  color.  j 
Plum  color. 
(Brownish  ] 
i     yellow  \- 
I          PPt.  ) 
No  change. 
Protocatechuic  acid 
/  Bluish-green  color,  \ 
\    red  color.  j* 
Violet  color. 
White  ppt. 
Gallic  acid  
Red  color. 
Deep  blue  ppt. 
No  reaction. 
White  ppt. 
Action  of  Acids. — To  effect  the  decomposition  of  the  tannins  by 
this  means,  a  quantity  of  each  sample  was  added  to  boiling  hydro- 
chloric acid  which  contained  2  per  cent,  of  absolute  gas.  All  of  the 
samples  dissolved  in  this  liquid.  As  the  boiling  progressed,  the 
liquids  to  which  the  tannins  from  chimaphila,  manzanita,  and  uva 
