402 
PHARMACY  OF  THE  CINCHONAS. 
tion  nearer  to  uniformity,  the  exhaustion  by  the  thinner,  more 
mobile  menstruum  must  from  these  physical  properties  be  better. 
And  when  it  is  borne  in  mind  that  the  exhaustion  of  Cinchona, 
even  when  in  very  fine  powder,  is  not  complete  either  in  regard 
to  extract  or  alkaloids,  by  four  or  even  by  live  pints  of  percolate 
from  16|,  tne  difficulties  in  arriving  at  accuracy  will  be  easily 
understood.  The  results  are  therefore  given  as  being  useful, 
though  not  fully  established,  but  as  quite  safe  in  their  relations 
to  pharmacy,  supported  as  they  are  upon  other  good  grounds, 
hereafter  to  be  alluded  to.  The  results  of  one  good  pair  of  the 
percolations  is  as  follows  : 
TOTAL  PERCOLATE 
4  PINTS. 
PERCOLATED  WITH  OFFICINAL  ALCOHOL, 
85  P.  C. 
PERCOLATED  WITH  OFFICINAL  DILUTED 
ALCOHOL,  39  P.  C 
Divided  into  7 
successive  por- 
tions, the  first  16 
fS.,  the  others  8 
fg.  each. 
Yield  of  Extract 
dried  at  105°  C. 
Yield  of  impure 
alkaloids. 
Yield  of  Extract 
dried  at  105°  C. 
Yield   of  im- 
pure alkaloids. 
From  each  por- 
tion 30  co.  =  1  f.5. 
taken  for  drying, 
and  for  assay. 
o 
CO 
rH 
£  u 
p  o 
© 
From  the 
whole  portion 
of  percolate. 
From  the  30 
c.e,  or  1  fS. 
From  the 
whole  portion 
of  percolate. 
o 
CO 
p  o 
£  ef 
6 
From  the 
(  whole  portion 
of  percolate. 
From  the  30 
c.e,  or  1  fS. 
From  the 
whole  portion 
of  percolate. 
1st  portion  16  fS. 
2d       "         8  f5. 
3d 
4th     "  " 
5th  " 
6th  " 
7th  " 
grs. 
61-5 
27-6 
18-2 
13-4 
9-7 
7-2 
5-9 
grs. 
984-0 
220-8 
145-6 
107-2 
77-6 
57-6 
47-2 
grs. 
7-15 
4-SO 
330 
3-00 
1-50 
1-30 
0-90 
grs. 
1144 
38-4 
26-4 
24-0 
12-0 
10-4 
7-2 
grs. 
57-2 
28-3 
13-0 
7-8 
6-0 
5-0 
4-5 
grs. 
915-2 
226-4 
104  0 
62-4 
48-0 
40-0 
36-0 
grs. 
7-30 
4-60 
2-08 
1-10 
•55 
•50 
•43 
grs. 
116-80 
36-80 
16*64 
8-80 
4-40 
4-00 
3-42 
Total, 
143-5 
1640-0 
21-95 
232-8 
121-8 
1432-0 
16-56 
190.86 
This  Cinchona  had  been  previously  found  to  contain  3*4  p.  c. 
of  impure  alkaloids,  which  would  give  261  grs.  as  the  proportion 
in  16^,  or  7680  grs.  of  the  powder.  These  percolations  give 
with  alcohol  232  grs.,  with  diluted  alcohol  191  grs.  The  loss  of 
29  grs.  in  the  first  may  be  due  chiefly  to  the  seven  processes  of 
assay  instead  of  one,  and  to  a  very  small  extent  to  the  more  per- 
fect exhaustion  in  the  case  of  the  one  critical  assay.  If  this  29 
grs.  be  adopted  as  the  error  for  loss  by  these  causes,  'and  be 
applied  to  the  results  from  diluted  alcohol,  the  difference  in  the 
yield  of  impure  alkaloids  by  the  two  menstrua  would  be  41  grs., 
or  15*7  per  cent,  of  the  whole,  in  favor  of  alcohol  as  a  men- 
struum. 
The  indications  which  may  be  drawn  from  a  comparison  of 
