74 
Tannin  and  Glycerin. 
j  Am.  Jour.  Phar.m.. 
t     Feb.  1, 1872. 
sallow  complexion  of  such  men,  women  and  children,  their  languid 
movements  and  their  enjoyment  of  heat,  all  alike  proclaim  that  they 
are  suffering  from  sluggish  action  of  the  liver.  The  conserve  of  Tar- 
axacum may  be  made  into  syrup  for  use.  Horses  and  valuable  dogsy 
sheep  and  poultry,  all  suffer  in  India  from  disease  of  the  liver.  A 
bolus  of  Taraxacum  conserve  to  a  horse,  and  a  pill  thereof  to  a  fowl, 
would  be  most  beneficial  and  act  as  a  curative  agent.  Rabbits  also 
suffer  greatly  from  liver  disease,  but  if  they  were  supplied  with  a  few 
(two  to  four)  green  Taraxacum  leaves  twice  or  thrice  a  week,  the 
mortality  resulting  from  this  (hitherto)  incurable  disease  would  disap- 
pear, and  rabbits  could  then  be  extensively  raised  for  the  market." — 
Pharm.  Journ.  and  Trans. ,  Dec.  30,  1871. 
TANNIN  AND  GLYCERIN. 
By  R.  Rother. 
Tannic  acid  is  frequently  prescribed  in  concentrated  solution  with 
glycerin  ;  but  tannin,  commercially  obtained,  possesses  various  im- 
purities which  either  remain  as  insoluble  turbidity  or  discolor  the  solu- 
tion. Firstly,  a  green  resinous  coloring  matter,  insoluble  in  water- 
but  soluble  in  strong  alcohol  and  glycerin,  invariably  occurs.  This 
contamination  results  from  the  solvent  action  of  the  ether  in  the 
original  process  of  extracting  the  tannin.  Secondly,  metallic  chips 
of  copper,  iron,  &c,  from  the.  vessels  in  which  the  tannin  was  dried 
are  never  absent. 
A  concentrated  solution  of  tannin  is  nearly  indispensable  among 
the  requisites  of  the  prescription  department.  An  aqueous  solution, 
however  concentrated  it  may  be,  will  spoil.  An  alcoholic  solution  is 
often  objectionable,  but  an  aqueous  solution,  containing  glycerin,  can 
be  utilized  on  most  all  occasions. 
This  solution  is  best  adjusted  by  weight ;  it  is  perfectly  stable,  clear 
and  transparent,  and  contains  one  troy  ounce  of  tannic  acid  in  two- 
troy  ounces  of  the  solution,  that  is  half  tannin  by  weight.  The  solvent 
is  the  other  half,  or  1-4  each  by  weight  glycerin  and  water.  More 
than  this  proportion  of  glycerin  cannot  be  used  to  advantage,  as  the 
liquid  becomes  too  thick  to  pour  conveniently.  This  solution  cannot 
be  prepared,  however,  by  directly  combining  the  three  ingredients,  as 
the  impurities  must  first  be  removed ;  and  the  only  preliminary  sol- 
vent for  this  purpose,  which  the  writer  has  found  to  answer  perfectly,, 
