ily as far as Messina. Their course was then to be
directed along the east and south coasts of Sicily to the west point of it;
from an island off this point they took their departure for the coast of
Africa, a distance of about ninety miles.

These Itineraries undoubtedly were drawn up in as accurate a manner as
possible; but till the time of Ptolemy they were of little service to
geography or commerce, as, for a private individual to have one in his
possession was deemed a crime little short of high treason. Geography as a
science, therefore, had hitherto made little advances; indeed the discovery
and example of Hipparchus, of reducing it to astronomical basis, seems to
have been forgotten or neglected till the middle of the second century. The
first after him, who attempted to fix geography on the base of science was
Marinus, of Tyre, who lived a short time before Ptolemy; of his work we
have only extracts given by this geographer. He divided the terms latitude
and longitude, which, as we have already stated, were introduced by
Artemidorus (A.C. 104) into degrees, and these degrees into their parts,
though this improvement was not reduced generally to practice before
Ptolemy, for we are informed by him, that Marinus had the latitude of some
places and the longitude of others, but scarcely one position where he
could ascertain both.

With regard to the extent of Marinus' geographical knowledge, or the
accuracy of his details, we cannot form a fair judgment from the fragments
of his works which remain. According to Ptolemy, he had examined the
history of preceding ages, and all the information that had been collected
in his own time, comparing and rectifying them as he proceeded in his own
account.

It will be recollected that the Periplus of the Erythrean Sea did not trace
the African coast lower down than Rhapta; but Marinus mentions Prasum,
which, according to that hypothesis, which fixes it in the lowest southern
latitude, must have been seven degrees to the south of Rhapta. So far,
therefore, the knowlege of the ancients, in the time of Marinus, respecting
the east coast of Africa extended; but, as neither he nor Ptolemy mentions
a single place between Rhapta and Prasum, it is probable that the latter
was not frequently or regularly visited for the purposes of trade, but that
commercial voyages were still confined to the limit of Rhapta. We have just
stated that Prasum, according to the most moderate hypothesis, m