524 
COLOR  TESTS  FOR  STRYCHNIA,  ETC. 
color  imparted  to  morphia,  followed  by  the  bleaching  of  the 
liquid.  This  same  test  divided  the  somewhat  unmanageable 
group  of  four  at  the  top  of  the  table  (cantharadine  and  aspara- 
gine,  and  caffeine  and  cinchonia)  into  two  small  groups  of  two 
each.  In  the  first  two  the  immediate  effect  of  the  permanga- 
nate was  a  red-brown  color ;  in  the  second,  a  pink.  Picrotoxia 
and  santonine  gave  the  same  color  (pink)  and  remained  undis- 
tinguished. The  last  and  ultimate  work  of  elimination  was 
effected  by  means  of  heat  applied  to  the  active  principle  in  its 
solid  state.  Cantharidine  was  found  to  be  wholly  dissipated  by 
the  heat  of  the  spirit  lamp,  while  asparagine  gave  a  bulky  car- 
bonaceous deposit.  And  caffeine  was  found  to  present  the  same 
difference  when  compared  with  cinchonia.  Lastly,  picrotoxia 
was  found  to  be  distinguished  from  santonine  by  the  bulky  car- 
bonaceous residue  with  the  first,  and  the  scanty  deposit  of  carbon 
with  the  second. 
Having  by  this  succession  of  tests  obtained  a  clue  to  the  ac- 
tive principle  with  which  we  have  been  dealing,  we  should  pro- 
ceed to  identify  the  substance  indicated  by  the  table,  through 
its  own  characteristic  tests. 
In  the  second  division  of  the  one  large  table  of  elimination, 
or  that  which  comprises  active  principles  colored  by  contact 
with  cold  sulphuric  acid,  (Table  II.,)  the  same  succession  of 
tests  is  employed.  Cold  concentrated  sulphuric  acid  at  once 
separates  this  group  of  seventeen  into  eight  smaller  groups  of 
one,  two  or  six  ;  and  the  subsequent  warming  and  heating  of 
the  colored  acid  solutions  occasions  such  marked  differences  of 
color  as  to  nearly  complete  the  work  of  elimination.  But  I 
have  added  columns  showing  the  effect  of  nitric  acid,  and  of  the 
solution  of  permanganate  of  potash.  The  application  of  heat 
to  the  alkaloids  themselves  did  not  prove  necessary  to  the  work 
of  elimination. 
I  submit  these  tables  primarily  as  specimens  of  Tables  of 
Elimination  ;  but  also  incidentally  as  tables  which  may  prove 
serviceable  to  the  Chemist.  I  am  not  certain  that  they  consti. 
tute  the  best  aid  which  could  be  devised  to  the  diagnosis  of  the 
alkaloids.  I  thought  that  they  might,  perhaps,  admit  of  being 
simplified  by  adding  to  the  three  columns  headed  "  sulphuric 
acid  "  a  fourth,  showing  the  deposit  of  carbon  resulting  from 
the  continued  application  of  heat  to  the  acid  solution  of  the  al- 
