109 
sopher, as subsequent to the Anabasis into Asia of Alex- 
ander ; it might be contended that it afforded no proof of 
their having been known at any earlier period, as at 
that of Hippocrates, though he was anterior to Theo- 
phrastus only 150 years. The Father of Medicine is 
supposed to have lived 4-50 years before the Christian era; 
but so little is known of his history, that among his works 
are thought to be included many of those of his pupils and 
successors. Sprengel was of opinion, that they embraced 
altogether a period of 250 years, and that some were there- 
fore subsequent to the time of Alexander, which he seems 
to assign as a reason for the knowledge displayed of Indian 
drugs ; but anterior even to the time of Hippocrates, some 
of these were known in Egypt, through which channel it 
is probable they first became known to the Greeks. 
Hippocrates is stated to have studied medicine under 
Herodicus, and to have embraced the philosophical hypo- 
thesis of Heraclitus ; he is therefore classed among the 
followers of Pythagoras ; and, like this philosopher, is 
described as having spent a considerable portion of his life in 
travelling in foreign countries, as Scythia, Colchis, Asia 
Minor, and perhaps Egypt, chiefly for the purpose of acqui- 
ring information, and studying the diversities of climate. 
Adopting the excellent abstract of Dr. Bostock, it appears 
that the philosophical tenets of Hippocrates were those of 
Heraclitus, " whose leading doctrine was, that fire is the 
prime origin of all matter, and that by the collision and pecu- 
liar combination of its particles, which are in perpetual 
motion, the four elements are produced. From this doctrine 
Hippocrates derived his leading principles of pathology, it 
lies at the foundation of all his medical hypotheses, and is 
brought forward in various parts of his works ;" as " the 
body itself is supposed to consist of the four elements, com- 
bined in different proportions in different individuals :"" and 
