EUPATORIUM PERFOLIATUM. 10 



contains, firstly, a free acid ; secondly, tannin ; 

 thirdly, extractive matter; fourthly, a o:umiiiy 

 matter ; fifthly, a resin ; sixthly, azote ; se- 

 venthly, lime, probably the acetate of lime; 

 eis^hthly, gallic acid, probably modified ; ninth- 

 ly, a resiniform matter, soluble in water and in 

 alcohol, and which seems to contain a bitter 

 principle. That the free acid may be obtain- 

 ed from all parts of the plant : that tannin is 

 obtained in much the largest quantity from 

 the leaves, and least from the roots : that the 

 extractive and gummy matter resides chiefly 

 in the roots : that the leaves and flowers also 

 contain a larger proportion of resin than the 

 roots : that azote exists in the flowers, leaves, 

 and roots. 



I have stated the presence of gallic acid ; 

 whether it depend upon the combination of 

 a free acid with tannin, or whether it is to be 

 ascribed to the existence of extractive mat- 

 ter, an opinion which Dr. Thoimson main- 

 tains, I do not pretend to determine: that 

 lime, a constituent of Peruvian bark, was also 



