Am.  Jour.  Pharm. 
Feb.,  1887. 
Ash  of  Cinchona  Bark. 
87 
In  Fluckiger  and  Hanbury's  Pharmacographia  the  following 
statement  is  made:  "The  cinchona  barks  yield  but  a  scanty  percent- 
age of  ash,  not  exceeding  3  per  cent.,  a  fact  well  according  with  the 
small  amount  they  contain  of  oxalate  and  kinate  of  calcium." 
With  regard  to  the  quantity  of  ash,  my  experience  is  that  culti- 
vated barks  yield  over  3  per  cent.;  the  average  of  three  hundred 
estimations  made  on  samples  from  this  country  was  calculated  at  3.42 
per  cent.  Renewed  and  old  natural  barks  are  the  poorer  in  mineral 
constituents,  but  they  never  fall  below  2  per  cent.  On  the  other 
hand,  young  and  branch  bark  gives  as  much  as  4  per  cent.,  and  it  is 
interesting  to  notice  that  the  leaves  afford  as  much  as  5,  and  some- 
times 6  per  cent.  With  regard  to  the  species  of  cinchona,  there  is  a 
marked  difference  in  the  amount  of  ash  yielded  by  each,  provided 
that  natural  bark  is  operated  upon.  The  crown  bark  is  richer  in  ash 
than  that  of  the  red,  and  the  red  richer  than  that  of  the  Ledger;  and 
knowing  that  crown  bark  grows  at  an  elevation  of  7,000  to  8,000 
feet,  the  red  at  5,000  to  6,000  feet,  and  the  Ledger  at  3,000  to  5,000 
feet,  the  altitude  may  have  something  to  do  with  this  gradation  of  ash 
in  the  different  species. 
When  gently  incinerated  at  a  low  red  heat  cinchona  bark  should 
always  leave  a  greyish-white  ash.  If  it  is  at  all  reddish,  it  points  to 
the  presence  of  dust  or  dirt  adhering  mechanically  to  the  sample ;  if 
weighed,  it  will  be  found  much  in  excess  of  that  obtained  from  clean 
bark.  The  two  most  dirty  samples  of  bark  I  have  met  with  came 
from  Ceylon,  leaving,  when  burnt,  a  reddish  residue  of  18.8  and  19.5 
per  cent,  respectively,  but  as  they  were  both  labelled  "  dust,"  neither 
the  vendor  would  be  blamed  for  the  impurity,  nor  could  the  pur- 
chaser rave  on  account  of  its  poverty  in  alkaloids. 
A  complete  analysis  was  made  of  the  ashes  of  the  two  species  of 
cinchona  grown  on  the  Nilgiris,  the  C.  officinalis  growing  in  the 
Dodabetta  plantation,  and  the  C.  succirubra  from  the  lower  elevation 
at  Naduvatam.  Notwithstanding  the  barks  were  from  different 
species  and  localities,  the  result  of  the  examination  shows  that 
there  is  a  great  similarity  in  the  composition  of  the  ash. 
C.  officinalis. 
C.  succirubra. 
Soluble  in  water 
Soluble  in  acid 
Residue 
27.33 
66.92 
5.75 
24.46 
69.94 
5.60 
100.00 
100.00 
