Am.  Jour.  Pharm.  ] 
July  1, 1873.  / 
Tincture  of  Rhubarb. 
307 
by  the  disturbance  of  the  sediment  when  the  tincture  is  decanted  in 
the  hurry  of  dispensing.  I,  therefore,  thought  that  a  little  time  could 
he  profitably  spent  in  some  experiments  with  the  view  of  so  amending 
the  officinal  process  as  to  overcome  the  difficulty  referred  to;  and  as 
my  efforts  in  this  direction  have  been  quite  satisfactory,  I  have  con- 
cluded to  give  the  result  for  the  benefit  of  others,  and  here  present 
the  following  modification  of  the  officinal  formula,  which  yields  a  tinc- 
ture that  will  keep  with  but  slight  precipitation  : 
Mix  the  glycerin,  alcohol  fort,  and  water.  Moisten  the  powders,, 
previously  mixed  together,  with  the  mixture  ;  pack  the  moistened  mass 
in  a  glass  jar  or  other  close  vessel,  and  let  it  stand  for  twenty-four 
hours.  Then  rub  the  powder  through  a  No.  20  sieve,  and  pack  it  in  a 
glass  funnel  prepared  for  percolation,  and  gradually  pour  upon  it  the 
remainder  of  the  menstruum,  and  when  it  has  all  been  absorbed  con- 
tinue the  percolation  with  diluted  alcohol  until  thirty-two  fluidounces 
are  obtained. 
As  a  preventive  measure  to  obviate  the  tendency  to  deposit  in  this, 
as  well  as  in  many  other  tinctures  and  also  fluid  extracts,  it  will  be 
well  to  have  the  receiving  vessel  perfectly  dry  or  else  rinsed  out  with 
a  portion  of  the  same  menstruum  which  is  to  be  used  in  the  percola- 
tion, and  the  percolate  after  a  half  flnidounce  or  ounce  has  passed 
should  be  occasionally  agitated.  This  last  simple  precaution  will  not 
infrequently  prevent,  at  least  in  a  measure,  the  tendency  to  deposit 
which  such  concentrated  solutions  might  otherwise  have. 
If  the  percolation  is  well  managed  in  making  fluid  extracts  and 
some  tinctures,  the  first  portions  of  percolate  which  pass  are  usually 
so  dense  and  so  supersaturated  that,  if  allowed  to  remain  long  in  this 
condition,  they  will  in  a  short  time  begin  to  let  fall  a  portion  of  their 
excessive  charge,  and  after  this  process  is  once  established  there  is  no 
telling  where  it  may  end.  And  such  solutions,  when  long  exposed  in 
this  supersaturated  condition,  become  a  helpless  prey  to  oxidation 
and  other  injurious  atmospheric  influences.    More  especially  is  this 
Jfy.    Pulv.  Rhei,  No.  40,  . 
"     Cardamomi,  No.  40, 
5  °°j 
f^iv  f  .^ij, 
f  3xvij, 
gss,  " 
Glycerine,  . 
Alcohol,  fort., 
Aquae-, 
f^xij  fS.vj, 
q.  s. 
Alcohol,  dil. 
