10. A King List
The astronomical observations recorded in the Diaries provide strong support for conventional chronology, but their scope is limited. Of the 180 Diaries preserved and dated, only six tablets record observations prior to 400 BC - four from the 5th century and one each from the 6th and 7th.
The 6th century tablet, Diary No.-567, records more than 40 observations that were shown in Feat of Clay to corroborate the date -567. (See Caeno homepage)
A similar study can be carried out on the oldest Diary, No.-651. A transliteration of the cuneiform text along with an English translation is provided for hardy souls who wish to evaluate the evidence.
12. Double dating
One Babylonian eclipse quoted in the Almagest is also known directly from a cuneiform tablet. The date inscribed on the tablet is Cambyses Year VII Month IV (Duzu), night of the 14th; the Almagest writes 7th year of Kambyses, which is the 225th year from Nabonassar, Phamenoth 17/18.
Modern computation agrees with the Cambyses tablet and the Almagest about the date of the eclipse, -522 July 17, but not much else. The three descriptions of the eclipse - Ptolemy's report in the Almagest, the account inscribed on the tablet and the computed one - do not match.13. Defamed
Lunar eclipses were the only Babylonian observations that entered Ptolemy's calculations. He judged their regular observations unreliable and argued convincingly for excluding them. Nevertheless, modern investigators find the Babylonians accurately observed and recorded many celestial events.
Presumably Ptolemy was aware that his calculations were incompatible with Babylonian observations, and he reacted as theorists often do - he focused on compliant evidence. Experimental results in complex studies are often contradictory. Hence the incongruous Babylonian data did not deter Ptolemy from the belief that celestial bodies move in perfect circles and have done so since time immemorial.