Am.  Jour.  Pharru. 
Dec,  l:  86. 
A  Study  of  the  Use  of  Mayer's  Reagent. 
581 
Name  of  al- 
kaloid. 0.100 
used  in  each 
experiment. 
Aconitine 
(Merck's 
cryst.) 
Aconitine, 
crude  from 
Aconite 
root 
Atropine 
Especial 
conditions. 
Berberine 
Brucine 
(Commer- 
cial) 
Brucine 
(Commer- 
cial) 
Brucine 
(Merck's 
pure) 
Cinchoni- 
dine 
Cinehonine 
I  Modified  re- 
agent No  1 
Modified  re 
agent  No.  - 
Modified  re- 
agent No.  1 
Modified  re- 
agent No.  2 
Sol.  slightly 
acid 
Sol.  nearly 
neutral.  ' 
Sol.  quite 
neutral 
Sol  moder- 
ately acid 
Sol.  nearly 
neutral. 
Mod,  reagt. 
No.  1. 
KI,  0.8  add- 
«  e,f  , 
25  per  cent, 
j  alcohol 
i  present  f 
jSol.  faintlv 
acid 
Sol.  neutral 
25  per  cent, 
alcohol  pre- 
sent. 
Sol.  acid,  25 
per  cent,  al- 
cohol pres- 
ent 
Mod.  rea- 
gent No.  1 
Sol.  quite 
neutral 
Sol.  quite 
acid 
Propor- 
tion of  al- 
kaloid in 
solution 
titrated. 
Mayer's  Solution,  1-20  Normal. 
Required 
to  give 
apparent 
excess. 
Added, 
giving 
large  ex- 
cess. 
Produces 
only 
slight 
precipit. 
Required 
for  com- 
plete pre- 
cipitation 
Excess  at 
end  of 
titration. 
Actually 
consu  nied 
1:200 
62 
7;3f 
2-2 
5-1 
1 : 200 
3-3 
6-0 
6-25 
1  :  400 
1  :200 
1  :  200 
1:200 
1:400 
1  :600 
1 : 200 
35 
5-2  . 
5*5 
8- 
71 
7'0 
76 
5  9 
63 
131 
14-9ff 
136 
14  Of 
150 
11-2 
30 
43 
40 
3-5 
56 
2-8 
101 
109 
9-6 
105 
9  4 
8-4 
1:400 
1 :600 
1  :400 
8- 
7-2 
11  6 
10*8 
10-04- 
i-  OJ 
3-2 
2-6 
84 
8-2 
1 : 200 
1:400 
1  : 600 
1:200 
3-7 
3-8 
4-2  to  4-6 
38 
02 
3-5 
1:4  0 
1 :400 
3-8 
6-0  to  7-2 
1  :200 
7-6 
8 -Of 
1-7 
65 
1:200 
51  . 
64 
69 
0-9 
6-0 
1  :400 
1  :400 
6-0 
6-8 
84 
7-6 
8-8 
8-  to  9  2+ 
1-400 
8'0 
Q-  trw  Q  Q4- 
y  i/O  y  oj 
1:600 
60 
92f 
1  : 200 
4'8 
6' 
i  ■'-{ 
JL  O 
5'7 
1 :400 
1 : 400 
6- 
48 
7-2 
7-6 
68 
1  :400 
1  :400 
5-8 
52 
8- 
9-  to  10  f 
1:400 
1 : 400 
6-4 
10' 
96 
ll-2f 
10  0 
1  : 400 
1 : 400 
11-6 
120 
13-2f 
1 :400 
11-2 
11  6f 
1  :100 
124 
138 
10 
12-8 
1:200 
1 : 200 
1  :200 
112 
156 
135 
123* 
26 
07 
130 
128 
1:200 
7-9 
10  8 
1:200 
12-8 
14  2 
