IV.] DIVISION INTO CONTINENTS. 67
thus established was formally expressed on the maps, so that
Delphi became the starting-point in their construction1.
A further point which presented itself for solution at an early
time to the geographers and map-makers was the Divi8ion of
division of the world into continents. On this the world into
subject a diversity of opinion existed, both as
regards the principle of division, and the limits at which the
boundaries were to be fixed. The triple system Twofold or
of partition into Europe, Asia, and Africa, which Threefold
ultimately carried the day, was at first the least
popular, for most of the authorities divided the world into two
parts, Europe and Asia—Africa (or, as the Greeks called it,
Libya) being regarded as part of the latter. This seems to
have been the case with Hecataeus, for where he is cited by
subsequent writers as an authority for the position of places
in Africa, the part of his work thus referred to is quoted in
some instances as a treatise on Asia, in others on Libya; from
which circumstance we may infer that the latter of these was a
subdivision of the former. Now as Africa was not unknown to
the Greeks of that time, an explanation seems to be required
of its omission in the division of the world into continents: and
this we may probably discover in the view that the principle of
partition turned on the cold and heat of the regions toward the
north and the south respectively, Europe—in which all that we
now call Russia in Asia was comprehended—being the colder
section, and Asia, including Libya, the warmer. This is confirmed
by our finding that Eratosthenes, who at a later time returned to
the twofold division, did so expressly on the ground of the
difference in temperature between those parts of
the globe2. The dividing line between Europe and
Africa was clearly marked by the straits at the
Pillars of Hercules, while the geographical features which were
1 Agathemerus, Geogr. i, 3. Speaking of the early attempts at map-
making, he says—011&> ofo iraXoioi r^v olicovfj&niv Hypa,<j>ov <rrpayy6\i}», ptgyv
ft KGLffdcu r^'EXXaSa, /cal ratfn?s AeX^otfr.
2 Varro, De re rust., i. 2. 3: Primum cum orbis terrae divisus sit in duas
partes ab Eratosthene maxime secundum naturam ad meridiem versus et ad
septentriones. See Berger, Geschichie dtr Erdkundt, i. p. 53,
5-2