31 
of the Romans. Prior to Dioscorides, we have only 
Theophrastus, who, having died 284 years before the 
Christian era, gives us, in his works on Plants and Mine- 
rals, some of the earliest accounts of two of the kingdoms 
of nature, as Aristotle, who shortly preceded him, does of 
the third. This age is subsequent only by a century to 
that of the " Father of Medicine, 11 whose Materia Medica 
can, I believe, be best ascertained, by first identifying that 
of his successors. 
In this long enumeration of authors, who, in conjunction 
with medicine, have treated also of Materia Medica, 
the chain of connexion is upon the whole so complete, 
that I have found it impossible to fix upon an appropriate 
place for treating of the Hindoo Materia Medica 
authors ; as these, like the writers on every other subject 
among this extraordinary people, are without any other 
than their fabulous chronology by which we may even 
approximatively ascertain the age in which they lived. We 
have, however, seen that the Persian authors at present in 
use in India, acknowledge having derived their information 
both from Indian and Arabian sources ; and the latter we 
know have copied or appropriated what they possessed in 
translation from the Greeks. The Persian Materia Medica, 
we shall not, therefore, be surprised at finding is one of the 
most copious ; as it is one of the most valuable, for tracing 
the history of the several drugs which have been in use in 
the Old World, from the most ancient to the present times: 
of these many still form some of the most important articles 
of our Materia Medica. Having, in the course of my 
investigations, referred what I found described as much as 
possible to both their Greek and Arabian originals, I have 
been able to form almost a complete circle of reference 
from one to the other, and thus, in a great measure, to 
ascertain what was original and what was copied in each. 
