xiv ADDRESS. 
of any one man. It will be found a work not issued from the 
press in the exuberant pruriency to keep out of view the la- 
bours of his predecessors, after its author “ had delivered three 
courses of lectures on this science,’’ not the work of one “ very 
unexpectedly called to teach the Materia Medica in the Uni- 
versity of Pennsylvania,” who had “ entered on the ent erprize 
with none of the advantages which would have been derived 
from the previous study of the subject with this precise and 
definite view”—not the production of one who “was pressed by 
the class” (nor twenty-one classes) “ that had formerly attend- — o 
ed him, with an earnestness which he could not well resist, t to 
prepare a work on the Materia Medica, or in other ' rords t 
print his lectures”—it is not such a work, of such an one, 
_ goaded against his will to hazard his reputa i #8 Lesa 
“But it will be found a work lit 
public, i in ‘the last j years of his. life, by. oné who entertained ele- 
vated opinions ot what aman should issue from the press, who 
might derive, or expect to derive solid reputation by his work— 
of one who after six years previous devotion to the study of Bo- — 
_ tany and to teaching it in the University, devoted | up’ 
venty years study, eeagesee, and pai of his ay fe 
