Strabo And Pliny Believed That Africa Terminated Under The Torrid Zone, And
That The Atlantic And Indian Oceans Joined.
Ptolemy, as we have just seen,
rejected this idea, and following the opinion of Hipparchus, that the earth
was
Not surrounded by the ocean, but that the ocean was divided into large
basins, separated from each other by intervening land, maintained, that
while the eastern coast of Africa at Cape Prasum united with the coast of
Asia at the bay of the Golden Chersonesus, the western coast of Africa,
after forming a great gulf, which he named Hespericus, extended between the
east and south till it joined India. The promontory of Prasum was
undoubtedly the limit of Ptolemy's knowledge of the east coast of Africa:
the limit of his knowledge of the west coast is not so easily fixed: some
suppose that it did not reach beyond the river Nun; while others, with more
reason, extend it to the Gulf of St. Cyprian, because the Fortunate
Islands, which he assumed as his first meridian, will carry his knowledge
beyond the Nun; and because, at the Gulf of St. Cyprian, the coast turns
suddenly and abruptly to the east, in such a manner as may be supposed to
have led Ptolemy to believe that it stretched towards and joined the coast
of India.
Of some of the interior parts of Africa Ptolemy possessed clear and
accurate information; regarding others, he presents us with a mass of
confused notions. He clearly points out the Niger, though he fixes its
source in a wrong latitude. In the cities of Tucabath and Tagana, which he
places on its banks, may perhaps be recognized Tombuctoo and Gana. The most
striking defect in his geography of the interior of Africa is, that he does
not allow sufficient extent to the great desert of Sahara, while the
southern parts are too much expanded. He places the sources of the Nile,
and the Mountains of the Moon in south latitude thirteen, instead of north
latitude six or seven; but the error of latitude is not so remarkable and
unaccountable as the very erroneous latitude which he assigns to Cape
Aromata, on a coast which was visited every year by merchants he must have
seen at Alexandria. The most difficult point to explain in Ptolemy's
central Africa is the river Gir, which he describes as equal in length to
the Niger, and running in the same direction, till it loses itself in the
same lake. What this river is, geographers have not agreed. It is mentioned
by Claudian, as resembling the Nile in the abundance of its waters.
Agethimedorus, a geographer of the third century, regards it and the Niger
as the same river.
What then was the amount of the knowledge of the ancients, as it existed
among the Romans, in the height of their power, respecting the form,
extent, and surface of the globe? If we view a map drawn up according to
their ideas, we are immediately struck with the form they assigned the
world, and perceive with what propriety they called the extent of the world
from east to west longitude or _length_, and the extent from north to
south latitude, or _breadth_. In some maps, especially that drawn up
from the celebrated Peutingerian Tables, which contain an itinerary of the
whole Roman empire, thirty-five degrees of longitude occupy twenty-eight
feet eight inches, whereas thirteen degrees of latitude are compressed
within the space of one foot.
Enter page number
PreviousNext
Page 215 of 524
Words from 111877 to 112458
of 273188
