'•}  Titration  as  a  Means  of  Assaying  Drugs.  477 
Gray 
IMKTRIC. 
Volumetric. 
. 
<+.< 
<+-.  d 
(4-1 
Fluid  Extract. 
O 
 ,  tn 
%\ 
0 
od  0 
urts. 
0  0 
u  ft 
0  rr 
0 
O 
O  O 
od  0 
urts. 
od  0 
lpSOl 
S  % 
~£ 
H 
.a  a 
si 
a  % 
I"5 
"SI  0 
«  H 
»=■ 
Aconite  Root,  .  . 
0-311* 
0-446 
1 '947 
0*640 
0-128 
0-437 
°'5I7 
0-599 
Belladonna  Leaves, 
0-300 
0-428 
1  "445 
0-380 
0  289 
0-3I5 
°'339 
0  310 
Belladonna  Root, 
0-338 
0-318 
1'135 
0-424 
0-338 
0*309 
O  34° 
°'335 
Bloodroot,  .... 
1-232 
1-560 
— 
t 
t 
Cinchona,  .... 
3-4i 
3 '49 
4-70 
3-21 
3-20 
Coca  L,eaves,  . 
0*969 
o-8o6 
o'68o 
0-563 
0-533 
Colchicum  Seed,  . 
0-682 
o-6oo 
— 
'  t 
t 
Conium  Fruit,  .  . 
0-567 
0-699 
— 
I 
Gelsemium,  .  .  . 
2-190 
0-836 
1-920 
0-400 
0-285 
0-277 
0*408 
C392 
Henbane,  .... 
0-265 
0-306 
0-231 
0-254 
Keller. 
Keller. 
I  015 
I  475 
2'01 
2  -90 
I'57° 
i'465 
1 '5i 
0'93 
Jaborandi,  .... 
0443 
0-884 
0-510 
0*166 
0*249 
0-266 
Beckurts. 
Beckurts. 
Nux  Vomica,    .  . 
1776 
1789 
3 '005 
i'584 
1-419 
1-419 
1-32 
I-340 
Stramonium  Seed, 
0-966 
0-3l8 
1-058 
0-296 
0*289 
0*218 
0*192 
0-295 
Veratrum  Viride,  . 
0-832 
I-030 
~~ 
0-246 
0-328 
*  These  figures  all  represent  the  percentage  of  alkaloids  in  the  fluid  extract,  which  in 
every  case  was  taken  from  the  same  bottle  for  all  the  methods.  The  fluid  extracts  were  of 
various  makes. 
f  Alkaloidal  residues  were  too  deeply  colored  to  admit  of  being  titrated. 
X  Not  titrated  because  of  the  volatility  of  the  coniine,  it  having  been  weighed  as  hydro- 
chloride. 
CONCLUSIONS. 
The  conclusions  to  be  drawn  from  these  results  have  virtually 
been  given  in  the  text  above.    Summed  up  briefly  they  are  : 
(1)  That  titration  with  volumetric  acid  solution  is  the  most  reliable 
and  trustworthy  method  of  assaying  alkaloidal  drugs  known  to  us 
to-day. 
(2)  That  gravimetric  results  as  heretofore  generally  reported  and 
made  use  of  are  in  many  cases  very  wide  of  the  truth,  and  hence 
unreliable. 
(3)  That  some  of  the  methods  employed  are  better  adapted  to 
some  drugs  than  to  others,  a  perusal  of  the  figures  best  showing  this. 
Inasmuch  as  several  of  these  methods  have  never  to  our  knowl- 
edge been  applied  to  some  of  the  fluid  extracts  examined,  it  might 
be  of  some  value  to  mention  here  some  of  the  modifications  and 
changes  made  in  them.  The  following  table  will,  we  hope,  make 
this  clear. 
