12 
Constitution  of  the  Alkaloids. 
( Am.  Jour.  Puarm. 
I    January,  1900. 
Desfosses. 
Godefroy. 
Wackenroden. 
Chevallier  and  Pelletan. 
Giesecke. 
Posselt  and  Reimann. 
Pelletier  and  Corriol. 
Dana. 
Robiquet. 
Pelletier. 
Henry  and  Delondre. 
Geiger  and  Hesse. 
1820.    Cinchonine  By  Pelletier  and  Caventou. 
Quinine  
Solanine  
1824.  Chelidonine  
1826.  Corydaline  
Berberine  
1827.  Conicine  
1828.  Nicotine  
1829.  Ariciue  
Sanguinarine   
1832.  Codeine  
Narceine   
1833.  Quinidine  
Atropine  
Hyoscyamine  
Aconitine  
Colchicine  
1835.    Thebaine  ,  .  "  Pelletier  and  Thiboumery. 
Every  drug  that  possessed  therapeutic  virtue  was  examined  for 
alkaloids,  and  as  soon  as  these  were  isolated,  they  were  examined 
by  physiologists,  who,  in  great  number,  were  as  much  interested 
as  the  chemists.  Magendie  notably  figured  in  these  physiological 
experiments,  as  his  celebrated  "  Formulaire,"  published  in  1821, 
bears  witness.  Of  these  many  publications,  perhaps  the  most 
classical  and  complete  is  that  of  Pelletier  and  Caventou,  on  "  Cin- 
chonine and  Quinine."  The  formula,  i.  e.,  the  composition  of  these 
alkaloids,  was  usually  not  determined  by  the  investigator,  but  by  the 
great  analysts  of  the  day — Liebig,  Regnault,  Laurent  and  Gerhardt. 
Knowing  what  the  empirical  formulas  of  these  substances  were, 
the  next  problem  that  naturally  engaged  the  attention  of  the 
chemists  was  their  constitution — how  were  these  many  atoms  of 
these  large  and  complex  molecules  combined  and  grouped.  Two 
theories  were  at  the  time  in  vogue,  and  both  were  distinct  and 
radically  different.  They  were  the  conjugated  theory  of  Berzelius 
and  the  amidogen  theory  of  Liebig. 
The  former  explained  the  constitution  of  the  alkaloids  by  assum- 
ing that  in  them  the  ammonia  was  contained  as  such,  and  to  it  was 
conjugated  the  various  radicals  that  caused  the  difference  in  proper- 
ties, composition,  etc.,  thus : 
NH3,  Ammonia.      .  .  , 
NH3.CH2,    Methylamine,  or  methyliak. 
NH3.C2H4,  Bthylamine,  or  ethyliak. . 
NH3.C6HU,  Nicotine. 
NH3.C6H4,  Aniline,  etc.,  etc. 
