to Dacia,
and into Armenia, Mesopotamia, and Assyria, and thus extending and
rendering more accurate the geographical knowledge of his subjects; but he
was also attentive to the improvement and commercial prosperity of the
empire. He made good roads from one end of the empire to the other; he
constructed a convenient and safe harbour at Centum Cellae (Civita Vecchia),
and another at Ancona on the Adriatic: he dug a new and navigable canal,
which conveyed the waters of the Nahar-Malcha, or royal canal of
Nebuchadnezzar, into the river Tigris; and he is supposed to have repaired
or renewed the Egyptian canal between the Nile and the Red Sea. He also
gave directions and authority to Pliny, who was appointed governor of
Pontus and Bithynia, to examine minutely into the commerce of those
provinces, and into the revenues derived from it, and other sources.

The emperor Adrian passed nearly the whole of his reign in visiting the
different parts of his dominions: he began his journey in Gaul, and thence
into Germany; he afterwards passed into Britain. On his return to Gaul, he
visited Spain; on his next journey he went to Athens, and thence into the
east; and on his second return to Rome, he visited Sicily; his third
journey comprised the African provinces; his fourth was employed in again
visiting the east; from Syria he went into Arabia, and thence into Egypt,
where he repaired and adorned the city of Alexandria, restoring to the
inhabitants their former privileges, and encouraging their commerce. On his
journey back to Rome, he visited Syria, Thrace, Macedonia, and Athens. By
his orders, an artificial port was constructed at Trebizond on a coast
destitute by nature of secure harbours, from which this city derived great
wealth and splendour.

The only writer in the time of Adrian, from whom we can derive any
additional information respecting the geography and trade of the Romans, is
Arrian. He was a native of Nicodemia, and esteemed one of the most learned
men of his age; to him we are indebted for the journal of Nearchus's
voyage, an abstract of which has been given. His accuracy as a geographer,
is sufficiently established in that work, and indeed, in almost all the
particulars respecting India, which he has detailed in his history of the
expedition of Alexander the Great; and in his Indica, which may be regarded
as an appendix to that history. He lived at Rome, under the emperors
Adrian, Antoninus, and Marcus Aurelius, and