102 
Tincture  Deposits. 
Am.  Jour.  Pharm. 
Feb.,  1884. 
Tinctura  Cardamomi  Composita. — This  deposit  occurs  principally 
in  minute  crystals  of  a  dirty  white  color,  with  a  small  proportion  of  a 
flocculent  substance.  The  crystalline  form  is  well  shown  by  a  low 
power  of  the  microscope,  which  reveals  several  different  forms,  a  few 
octahedra,  while  others  are  hexagonal  prisms  with  pyramidal  apex  and 
base,  besides  others  more  difficult  to  make  out. 
The  deposit  was  first  washed  with  proof  spirit  until  the  washings 
passed  colorless  or  nearly  so,  then  boiled  with  water  and  filtered.  The 
filtrate  was  examined  for  metals,  very  carefully  for  potassium,  and  also 
for  tartaric  acid,  but  gave  no  evidence  of  the  presence  of  either,  prov- 
ing that  the  deposit  is  not  acid  tartrate  of  potassium,  as  I  think  is  the 
usual  opinion. 
The  precipitate  was  then  boiled  with  a  strong  solution  of  sodium 
carbonate  for  about  three  hours  and  filtered.  The  insoluble  portion 
was  examined  for  metals,  calcium  was  alone  found. 
Looking  at  the  constituents  of  the  tincture  I  find  that  the  deposit 
must  consist  of  one  or  more  of  the  following : — Tartrate  or  malate  of 
calcium  or  oxalate  of  calcium. 
The  alkaline  filtrate  was  therefore  divided  into  four  portions.  To 
the  first  was  added  excess  of  solution  of  acetate  of  lead,  the  precipitate 
filtered  off  and  dried  upon  a  water-bath,  ammonia  added  again  dried, 
then  a  few  more  drops  of  ammonia,  and  lastly  digested  with  alcohol, 
which  would  dissolve  any  malate  of  ammonium  if  present;  on  evapora- 
tion of  the  alcoholic  solution  no  residue  was  obtained,  proving  absence 
of  malate  of  calcium. 
To  the  second  portion  excess  of  acetic  acid  was  added,  then  solution 
of  calcium  chloride;  no  precipitate  was  formed,  showing  absence  of 
oxalate  of  calcium. 
To  the  third  portion  nitric  acid  was  added  to  exact  neutrality,  a 
slight  excess  of  nitrate  of  silver,  and  lastly  ammonia  in  slight  excess  ; 
on  boiling  for  a  short  time  a  fine  mirror  of  silver  was  obtained  on  the 
sides  of  the  tube',  giving  strong  suspicion  of  tartaric  acid. 
To  the  fourth  portion  were  added  excess  of  acetic  acid,  a  little 
potassic  hydrate,  then  more  acetic  acid  (to  ensure  acidity),  and  lastly  a 
small  quantity  of  alcohol.  On  setting  aside  for  a  short  time  a  white 
crystalline  precipitate  formed,  which  on  the  addition  of  strong  sulphuric 
acid  and  gently  warming  gave  off  the  odor  of  burnt  sugar,  indicating 
the  presence  of  tartaric  acid. 
A  small  portion  of  the  original  aqueous  solution  was  boiled  with 
