38o 
Tincture  of  Kino. 
fAm.  Jour.  Pharm. 
\     August,  1903. 
authorities,  as,  for  example,  the  National  Dispensatory,  in  which 
occurs-  the  following  unqualified  statement :  "  Made  with  alcohol 
and  properly  preserved,  it  will  remain  limpid,  but  if  made  with 
diluted  alcohol  it  will  gradually  lose  its  astringency  and  become 
gelatinous." 
However,  a  critical  review  of  some  of  the  previously  published 
papers  and  notes  convinces  me  that  the  favorable  results  reported 
for  some  of  these  formulas  was  largely  due  to  the  diluted  alcohol 
recommended  as  the  menstruum.  Although  the  proposers  attributed 
the  success  to  other  causes,  a  number  of  sign  boards  point  toward 
the  menstruum. 
The  use  of  strong  alcohol  was  probably  advocated  on  the  theory 
that  pectin  was  supposed  to  be  an  ingredient  of  kino  and  the  cause 
of  the  gelatinization.  Regarding  this  theory,  Mr.  Redwood 
(American  Journal  of  Pharmacy,  Vol.  XIV,  folio  259)  writes  : 
"On  the  presumption,  therefore,  that  the  gelatinization  of  this  tinc- 
ture depends  on  the  presence  of  pectin,  rectified  spirit  has  been  used 
in  its  preparation  instead  of  proof  spirit,  with  the  view  of  obviating 
this  result,  pectin  being  insoluble  in  rectified  spirit.  This  substitu- 
tion, however,  has  not  been  found  to  effect  the  intended  object,  as 
the  tincture  prepared  with  rectified  spirit  is  subject  to  the  same 
change  as  that  made  with  proof  spirit."  And  then  this  author,  at 
that  time  already  blazoned  the  path  for  a  more  satisfactory  prepara- 
tion in  the  following  sentence  :  "  The  most  effectual  means  of  pre- 
venting this  change  would  probably  be  in  preparing  the  tincture, 
to  extract  as  speedily  as  possible  the  most  soluble  part  of  the  kino, 
without  allowing  the  solution  thus  formed  to  remain  long  in  contact 
with  the  altered  and  less  soluble  constituents." 
In  a  letter  to  the  editor  of  the  American  Journal  of  Pharmacy 
(American  Journal  of  Pharmacy,  Vol  XXI,  folio  297),  Mr.  Benja- 
min Canavan  states  <(  that  by  making  the  preparation  with  proof 
spirit,  instead  of  rectified  spirit,  I  obtained  a  tincture  which  keeps 
perfectly  well,  is  more  astringent  and  less  stimulating  than  we  have 
been  before  able  to  obtain  it."  This  statement  is  subsequently  con- 
firmed by  R.  H.  Stabler  (American  Journal  of  Pharmacy,  Vol. 
XXIII,  folio  123). 
L.  Myers  Connor  (American  Journal  of  Pharmacy,  1873,  folio 
260)  ascribes  the  permanency  of  his  preparation  to  the  use  of  mag- 
nesium carbonate,  but  it  is  to  be  noted  that  the  menstruum  used  was 
diluted  alcohol. 
