THE 
AMERICAN JOURNAL OF PHARMACY. 
APRIL, 1 847. 
ART I.— A REVIEW OF CERTAIN DOCTRINES ADVANCED BY 
THE CELEBRATED LIEBIG, AND SANCTIONED BY GREGORY 
AND KANE * By Robert Hare ; M. D. ; Professor of Chemistry 
in the University of Pennsylvania. 
The means by which the various ferments respectively, 
produce their appropriate changes, are involved in the 
greatest obscurity. Some important additions have been 
made to our knowledge, as respects the facts. The ferments 
have all been shown to be vegeto-animal matter in a state 
susceptible of oxidizement, and an analogy has been infer- 
red between their influence and that of some other agents, 
supposed to act by what has been called catalysis, which 
is a new name given by Berzelius, to an old mystery. It 
has long been known that there are two modes by which 
chemical changes are to be excited. In one of these, the 
presentation of one or two extraneous elements causes de- 
composition and recomposition, by the reactions between 
the elements so presented and those subjected to altera- 
tion, as in the various cases of elective affinity : in the 
other mode, substances are made to re-arrange their consti- 
tuents into one or more new combinations, by the presence 
* See " Traite," u Introduction/' p. xii. See also Kane's Elements, 
p. 31. Gregory's Outlines of Organic Chemistry. 
VOL. XIII. NO I. 1 
