Ancient calendars and constellations

ANCIENT CALENDARS AND CONSTELLATIONS
By the Hon. EMMELINE M. PLUNKET
WITH ILLUSTRATIONS
LONDON JOHN MURRAY, ALBEMARLE STREET, W. 1903
The Papers here collected and reprinted, with some alterations, were not originally written as a series; but they do, in fact, form one, inasmuch as the opinions put forward in each Paper were arrived at, one after the other, simply by following one leading clue.
This clue was furnished by a consideration of statements made by Professor Sayce in an article contributed by him in 1874 to the Transactions of the Society of Biblical Archæology .
At page 150 he thus wrote:—
“The standard astrological work of the Babylonians and Assyrians was one consisting of seventy tablets, drawn up for the Library of Sargon, king of Agane, in the 16th century B.C.”
And again at page 237:—
“The Accadian Calendar was arranged so as to suit the order of the Zodiacal signs; and Nisan, the first month, answered to the first Zodiacal sign. Now the sun still entered the first point of Aries at the vernal equinox in the time of Hipparkhus, and it would have done so since 2540 B.C. From that epoch backwards to 4698 B.C. Taurus, the second sign of the Accadian Zodiac, and the second month of the Accadian year, would have introduced the spring. The precession of the equinoxes thus enables us to fix the extreme limit of the antiquity of the ancient Babylonian Calendar, and of the origin of the Zodiacal signs in that country.”
Not many years after this sentence had been penned, archæologists, as the result of much evidence, came to the firm conviction that the date of Sargon of Agane was far earlier than had been at first supposed; and it was placed by them, not “in the 16th century B.C.,” but at the high date of 3800 B.C.
It was in endeavouring to account for the choice by Accadian astronomers of Nisan as first month of the year, and of Aries as first constellation of the Zodiac, at a date when that month and constellation could not have “introduced the spring,” that a possible solution of the difficulty presented itself to my mind—namely, the supposition that the Accadian calendar had been originated when the winter solstice , not the spring equinox , coincided with the sun’s entry into the constellation Aries. This coincidence took place, as astronomy teaches us, at the date, in round numbers, of 6000 B.C.