Am.  Jour.  Pharm.") 
Feb.,  1884.  / 
Tincture  Deposits. 
101 
TINCTURE  DEPOSITS.1 
By  R.  A.  Cripps. 
Contribution  from  the  Research  Fund  of  the  School  of  Pharmacy  Students' 
Association. 
Every  pharmacist  must  have  noticed  the  fact  that  most  of  his  tinc- 
tures, after  having  been  filtered,  deposit  sooner  or  later  a  more  or  less 
bulky  sediment.  The  importance  of  knowing  the  nature  of  these 
deposits  at  once  suggests  itself  to  every  one.  Is  it  that  they  contain 
some  of  the  active  principles  of  the  drugs,  or  are  they  only  gummy  or 
albuminous  matter,  of  no  value  in  medicine?  It  is  with  the  view  of 
throwing  some  light  upon  this  question  that  I  have  undertaken  their 
investigation,  feeling  that  my  work,  however  imperfect,  will  be  one 
step  towards  a  deeper  knowledge  of  the  chemistry  of  some  of  the 
pharmacist's  practical  difficulties. 
1.  Tinctura  Calumbce. — The  deposit  in  this  tincture  usually  occurs 
in  flaky  pieces  of  a  light  olive-brown  color,  mixed  with  a  gummy- 
looking  substance  of  the  same  nature.  Under  the  microscope  the  sample 
under  examination  formed  a  very  interesting  object,  as  it  consisted 
principally  of  finely-formed  starch  granules,  similar  to  a  mixture  of 
arrowroot  and  wheat  starches,  showing  very  distinctly  the  hilum  and 
concentric  rings,  and  with  the  polariscope  a  fine  black  cross ;  with  the 
starch  was  mixed  a  quantity  of  matter  of  no  definite  structure,  and  a 
few  very  fine  tubular  vessels  of  a  bright  yellow  color. 
The  starch  was  confirmed  by  adding  iodine  to  the  cooled  decoction 
of  the  deposit,  when  the  usual  blue  color  was  developed. 
After  washing  well  with  proof  spirit  (until  the  washings  passed 
nearly  colorless)  the  deposit  was  boiled  with  water,  and  afterwards  with 
very  dilute  sulphuric  acid  ;  it  gave  a  brownish-yellow  solution,  which 
on  dilution  with  spirit,  boiling  and  addition  of  dilute  solution  of 
iodine  in  iodide  of  potassium,  gave  no  green  spangles  indicative  of 
berberine,  nor  did  it  possess  any  markedly  bitter  taste,  showing  the 
absence  of  more  than  traces  of  colombin  or  colombic  acid. 
The  deposit  in  tincture  of  calumba  may  therefore  be  said  to  contain 
none  of  the  active  principles  of  the  drug,  and,  except  for  the  incon- 
venience of  filtering,  is  of  no  consequence. 
1  Read  at  a  meeting  of  the  School  of  Pharmacy  Students'  Association, 
Nov.  29. 
