xi INTRODUCTION. 
“the Homer of his profession.” He first made experi- 
ments with different medicinal plants (of which he enume- 
rates two hundred and thirty) on the human frame, 
which greatly tended to increase his knowledge, and by 
the observations deduced from them, he was supposed not 
only to have been able to prolong the lives of others, but 
his own; for he died at the age of one hundred and nine 
years, free from all disorders of mind and body. 
To the Philosopher of Trnth,* to him who killed himself 
rather than live when disappointed in his scientific investi- 
gations, we were first indebted to the introduction of 
botany as a philosophical science. His views and ideas were 
more fully followed out by his disciple Theophrastus, who 
gave a full account of all plants known in his time; in his 
work, xeg: Duray iorogias, he enumerates about five hundred 
species, all medicinal, but often applying the same name 
to plants totally dissimilar in their botanical and physio- 
logical characters. He paid great attention to the physio- 
logy of plants, and was aware of the difference of the 
exogenous and endogenous, or monocotyledons and dico- 
tyledons of the moderns. He was also aware that nutri- 
tion was conveyed to plants by the leaves. We next come 
to Dioscorides the Cilician, who lived in the time of Nero ; 
he enumerated about six hundred plants, and Pliny the 
elder increased the number to one thousand. He, how- 
ever, acknowledged that there were many more undescribed, 
and which probably would be found useful for medicinal 
purposes. ‘Then came the almost complete annihilation of 
the sciences by the barbarian inroads into civilized Europe. 
* Aristotle, who drowned himself because he could not discover the 
cause of the flux and reflux of the waters in the Euripus. 
