4  Mayer's  Reagent  for  Estimating  Alkaloids.  {Am'ji0n^if87arm' 
The  following  table  gives  the  results  of  the  experiments  made  with 
reference  to  the  composition  of  the  precipitate: 
6  . 
go 
sis 
6 
<u 
6  . 
be 
W 
zed. 
I 
Ph->  • 
«M  ^ 
verage  wei 
alkaloid  in 
prec.  2  app 
8* 
aly 
Name  of  alkaloid. 
Bight  o 
ontainii 
alkalo 
Weight  o 
analy: 
Hg.  in 
analy: 
Atoms 
i. 
prec.  an 
Atom 
jleculai 
of  pre 
*° 
O  O 
a 
3 
Aconitine  
179-188 
54-8 
182-5 
27-5 
0-73 
55 
235 
954-1002 
216-245 
54-4 
220 
51 
073 
69 
1-6 
624-708 
2003 
550 
253 
042 
75? 
2-0 
6703 
190-214 
48  9 
'205' 
30 
059 
75 
233 
749-843 
Cinchonidine  .... 
348-870 
28-5 
352 
603 
0-92 
192 
4-65 
1072-1140 
Cinchonine  
324-348 
300 
339 
625 
0'96 
176-5 
4-28 
988-1072 
Cocaine  
210-270 
40-7 
246 
50 
0-76 
94 
2-25 
Colchicine  
155-180 
159 
34 
0-58 
25? 
?4 
'491-571 
240-256 
'  40-8  ' 
245 
44 
109 
105 
410 
1190-1270 
Gelsemine  
185-200 
524 
503 
1-02 
50  3 
1-61 
8163 
Hydrastine  
200-210 
47-6 
'2LO' 
37 
073 
73 
2  28 
8343 
Hyoscyamine  .... 
222-250 
435 
228 
46 
066 
82 
1-87 
642-7  3? 
Morphine  
190-204 
486 
202 
42 
0-60 
60 
1-35 
541-5821 
295-340 
308 
81 
0-84 
127? 
2-084 
614-707 
3L0-335 
'  30-8  ' 
325 
64 
1-04 
161 
411 
1004-1085 
258-274 
379 
264 
57 
0  95 
107 
2-81 
860-913 
What  I  desire  to  show  by  these  tabulated  results  is  that,  making 
all  allowance  for  such  deviation  from  the  normal  composition  as  we 
may  look  for  in  complex  compounds  formed  under  such  circumstances 
as  those  of  my  experiments,  a  few  only  of  the  precipitates  appproxi- 
mate  a  composition  corresponding  with  the  formulae  assigned  them 
by  Prof.  Mayer.  From  the  data  here  presented,  it  would  appear 
that  in  the  case  of  the  cinchona  alkaloids,  emetine,  gelsemine  (?)  and 
strychnine,  the  precipitate  contains  one  atom  of  mercury  for  each 
alkaloidal  molecular  group.  For  the  cinchona  alkaloids  and  emetine, 
at  least,  the  normal  formula  is  probably  B/'J^Hglg,  R  representing 
the  alkaloidal  radical.  There  is  some  uncertainty  about  the  record  I 
have  of  the  single  experiment  made  with  gelsemine.  If  there  is  not 
some  mistake  in  the  recorded  figures,  the  composition  of  the  precipi- 
tate is  quite  anomalous,  but  'the  formula  of  gelsemine  cannot  be  con- 
sidered to  be  as  yet  positively  fixed.5 
1  The  higher  figures  in  this  column  were  generally  obtained  only  when  the  precipitate  was 
left  some  hours  before  filtering. 
2  Precipitate  collected  soon  after  it  is  formed. 
3  Assuming  that  it  contains  one  equivalent  of  alkaloid. 
4  The  precipitate  seems  to  contain  CI  as  well  as  L 
5  My  associate  in  analytical  work,  Mr.  F.  A.  Thompson,  is  making'a  new  study  of  the  alka- 
loids of  gelsemium,  which  will  shortly  be  published 
