Note 39 — INTRODUCTION

Three different positions of the equinox are given in three different Babylonian tablets, namely, 10°, 8° 15′, and 8° 0′ 30″ of Aries. (Kugler, Mondrechnung, p. 103; Ginzel, Klio, i. p. 205.) Given knowledge of this kind, and the practice of formulating recurrences in cycles, it is scarcely conceivable that the Babylonians should not have invented a cycle for precession. It is equally intelligible that they should only have reached a rough approximation; for the precessional period is really about 27,600 years and not 36,000. It is to be observed that Plato’s “perfect year” is also 36,000 solar years (Adam’s Republic, vol. ii. p. 302), and that it is probably connected with the precession of the equinoxes. (Cf. Tim. 39 d, a passage which is most easily interpreted if referred to precession.) This suggestion as to the origin of the “Great Year” was thrown out by Mr. Adam (op. cit. p. 305), and is now confirmed by Hilprecht, The Babylonian Expedition of the University of Pennsylvania (Philadelphia, 1906).