Asia

Ptolemy's second book divides the inhabited world into four quarters and puts each in familiarity with one of the four triplicities of signs. Asia is the only landmass in the scheme that falls across two of them.

The southeast quarter, which Ptolemy fills with India, Persia, Babylonia, Mesopotamia and Assyria, is in familiarity with the earth triplicity, Taurus, Virgo and Capricorn. The northeast quarter, which he calls Scythia and populates with the lands north and east of the Caspian, is in familiarity with the air triplicity, Gemini, Libra and Aquarius. Ptolemy assigns planetary co-rulers to each quarter as well, and those assignments are not identical to the ordinary triplicity lords, so this entry does not name them rather than report one as the other.

Splitting Asia is not a failure of the scheme. The scheme is not a map of continents. It is a division of the oikoumene, the inhabited world as a second century Alexandrian understood it, by compass quarter from a centre near the Mediterranean, and continents are simply not what it divides. Reading it as geography produces the impression of an error where there is none.

What the quarter assignment is used for is mundane astrology, the reading of eclipses, comets and great conjunctions for their effect on regions. Ptolemy's chorography is the lookup table that tells such a reading which part of the world an event in a given sign concerns.

Beyond the chorography, Asia's place in this atlas's astrological material is as the source of most of it.

The technical apparatus of horoscopic astrology is built on Mesopotamian celestial omen work and Mesopotamian mathematical astronomy, and the zodiac of twelve equal thirty degree signs is a Babylonian construction that Greek astronomy inherited rather than invented. The Hellenistic synthesis of the last centuries before the common era took that material, combined it with Egyptian and Greek elements, and produced the natal astrology this vocabulary belongs to.

The traffic then ran in several directions. Greek astrological texts were translated into Sanskrit and reworked into the Indian tradition, where the technique developed along its own line and is practised continuously to the present day. From the eighth century the Abbasid translation movement carried Greek, Persian and Sanskrit astrological material into Arabic, where it was systematised and extended before passing into Latin Europe from the twelfth century onward.

So the medieval European house catalogue this atlas records under so many entries is an Asian inheritance twice over, Babylonian in its zodiac and Arabic and Persian in the form Europe actually received. Lilly's Christian Astrology of 1647 sits at the end of that chain, and the chain is the reason a continent entry belongs in an astrological vocabulary at all. The atlas records the transmission as history, and states each attribution at the level the scholarship supports rather than more precisely.

Sources A History of Western AstrologyNicholas Campion with Christian AstrologyWilliam Lilly