Introduction 



5 



leaves of 57 plants varied from 0-352 to 0-768 per cent., and averaged 

 0-545 per cent. In individual plants at a single picking the highest 

 alkaloid content in 1911 was 0-925 and the lowest 0-200, and in 1912 

 the highest was 0-882 and the lowest 0-292. {Jour. Agric. Res., i. 2, 

 Nov., 1913.) 



The variation in the percentage of poisonous principle was well 

 shown in several papers read at the International Congress of AppHed 

 Chemistry held at Washington and New York in 1912 (see Chemist and 

 Druggist reports). For example, Carr stated that at the Wellcome 

 Materia Medica Farm, Dartford, Kent, the efiect of manuring on medi- 

 cinal plants has been tested for some years, and the effect of the more 

 common fertiUsers on Atropa Belladonna was shown by the following 

 table: — 



In considering these results it must be remembered that the soil 

 is naturally suited to the plant, and the percentage of alkaloid obtained 

 without added fertiUsers is already high. The low figures obtained 

 in 1907 were probably due to the seasonal conditions. Atmospheric 

 conditions have a modifying influence. 



It was also shown that the Belladonna root of commerce varies 

 greatly in alkaloid strength. "In a number of analyses made of com- 

 mercial roots, variations from 0-27 to 0-69 per cent, have occurred. 

 The average of twenty-one analyses of German and Austrian commercial 

 roots was 0-40 per cent. Other observers have recorded similar results. 

 Chevalier {Compt. Rend., 1910, 150, 344) gives the following figures for 

 Continental roots: French, 0-300 to 0-450 per cent; Austrian, 0-251 to 

 0-372 per cent.; ItaUan, 0-107 to 0-187 per cent. Henderson has 



