Twelfth-Parts in Mesopotamia
Some readers may be interested in a brief passage by historian Francesca Rochberg. Twelfth-parts were popular in Hellenistic astrology. However, they are much older than Hellenistic astrology. In the passage, Rochberg discusses the pre-Hellenistic use of twelfth-parts by Babylonian astrologers. Shockingly, Babylonian twelfth-parts date back to at least the 5th century BCE.
In the passage, she notes that the Babylonians were using the twelfth-parts of the zodiac in the context of their omen lore. There is evidence of this from only a couple hundred years of the first evidence of a regularized twelve-sign zodiac (circa 700 BCE). Therefore, this important division of the signs in Hellenistic astrology is Babylonian in origin and almost as old as the zodiac itself.
You can read the entire section on Babylonian twelfth-parts in Google Books by following the link below:
More on Rochberg
For more on Rochberg’s work, please check out U.C. Berkeley’s introductory interview:
More on Twelfth-Parts
Most of the major Hellenistic astrologers made use of the twelfth-parts. They are a key technique of Hellenistic astrology and a valuable addition to the traditional astrologer’s toolbox. However, astrologers often neglect them today.