icate an advanced degree of knowledge and
civilization. We are not aware of a similar fact, with respect to the
proportionate value of iron and silver, being recorded of any other nation
of antiquity. It is not to be supposed, however, that the cheapness of
gold, measured by iron and silver, could long continue in Arabia, unless we
believe that their intercourse with other nations was very limited; because
a regular and extensive intercourse would soon assimilate, in a great
degree at least, the value of gold measured by iron and silver, as it
existed in Arabia, to its value, as measured by the same metals in those
countries with which Arabia traded.

But to return from this slight digression;--Artemidorus has been already
mentioned as a geographer subsequent to Agatharcides, who copied
Agatharcides, and from whom Diodorus Siculus and Strabo in their turns
copied. There were two ancient writers of this name born at Ephesus; the
one to whom we have alluded, is supposed to have lived in the reign of
Ptolemy Lathyrus, A.C. 169; by others he is brought down to A.C. 104.
Little is known respecting him; nor does he seem to have added much to
geographical science or knowledge: he is said by Pliny to have first
applied the terms of length and breadth, or latitude and longitude. By
comparing those parts of Diodorus Siculus and Strabo, which they avowedly
copy from him, with the track of Agatharcides: in the Red Sea, we are
enabled to discover only a few additions of importance to the geographical
knowledge supplied by the former: Agatharcides, it will be remembered,
brings his account of the African side of the Red Sea no lower down than
Ptolemais: he does not even mention the expedition of Ptolemy Euergetes to
Aduli; nor the passage of the straits, though Eratosthenes, as cited by
Strabo, proves that it was open in his time. In the time of Artemidorus,
however, the trade of Egypt on the coast of Africa had reached as low down
as the Southern Horn; that this trade was still in its infancy, is apparent
from a circumstance mentioned by Strabo, on the authority of Artemidorus;
that at the straits the cargo was transferred from ships to boats; bastard
cinnamon, perhaps casia lignea or hard cinnamon, is specified as one of the
principal articles which the Egyptians obtained from the coast of Africa,
when they passed the straits of Babelmandeb.

The next person belonging to the Alexandrian school, to whom the sciences
on which geograp