THE PRINCIPLES 
OF 
PHARMACOGNOSY. 
THE MISSION OF PHARMACOGNOSY. 
THE substances which are employed medicinally for their 
remedial action are either the products of human skill or they 
belong directly to the two organic natural kingdoms. Among 
the medicinal substances formed through chemical operations 
we meet, indeed, with such as are produced only by certain 
definitely conducted chemical or physical processes, as, for 
example, the acids, iodine, bromine, chloral, phenol, glycerin, 
alcohol, and the alkaloids, be it that chemical industry starts 
from materials belonging to the inorganic kingdom, or that its 
first point of departure, as in the two last-named examples, falls 
within the circle of organic nature. In some rare cases only 
(mineral waters, for instance) is it sufficient to merely choose a 
- suitable form for that which nature offers ready for use; more 
frequently chemical skill is directed toward the isolation of 
active principles from plants (exceptionally also from animals 
or animal substances, or from the mineral kingdom), and to the 
separation of these principles from associated substances, or, 
in other words, to their purification. In all these cases the 
. _ object i is to ploce at the Sisppent ot ot medical science bodies Meoae oe 
