“In the month of Sebat (January) the 1st day during the year Bel-haran-saduya (648 B.C.).”
The result of this mission was not satisfactory. The eclipse had been predicted, but although the state of the atmosphere did not allow of observation, the attesting of this failure proves the care with which every circumstance that could serve to explain the phenomenon was noted. Here is an observation which was entirely successful:
“To the director of observations my Lord, his humble servant Nabu-shum-iddin, Great Astronomer of Nineveh writes this: May Nabu and Marduk be propitious to the director of these observations, my Lord.
“The 15th day we observed the node of the moon, and the moon was eclipsed.”
Here is a more complicated observation:
“To the king, my Lord, may the Gods Nabu and Marduk be propitious, may the great gods grant to the king, my master, long life, the benefits of the flesh and satisfaction of the heart.
“The 27th day the moon disappeared; the 28th 29th and 30th day we continually observed the node of the obscuring sun. The eclipse did not take place. The 1st day (of the following month) we saw the moon during the first day of the month Tammuz (June) above the star Mercury of which I have previously sent an observation to the king my master. In its course during the day of Anu, around the shepherd star (the planet Venus), it was seen declining: on account of rain the horns were not very distinctly visible, and so it was in its whole course. The day Anu I sent the observation of its conjunction, to the king my master. It was prolonged and was visible above the star of the Chariot in its course during the day of Baal; it disappeared towards the star of the Chariot.
“To the King, my Lord, peace and happiness.”
The discovery of the precession of the equinoxes is generally attributed to Hipparchus. It was he, indeed, who taught this fact to the Greeks, and he estimated its yearly amount as from 36 to 39 seconds; but it is certain that he learned about it in Chaldea, and that he obtained the elements of his calculations from the astronomical observations made on the lower Euphrates. All the astronomical knowledge of the Ninevite savants had the same point of origin.
Two thousand years before our era, from the time of a king of Agade called Sharrukin (Shargani-shar-ali), and who is usually known as Sargon I (the Ancient), the precession of the equinoxes was an observed and calculated fact, since it had already brought sufficient disturbance into the calendar to make a corrective element necessary. Sargon had given a brilliancy to his century which the learned men of Nineveh only echoed. In his time there was a library at Agade, the importance of which we can judge by the fragments which were preserved at Nineveh. We are certain that at these remote times the great divisions of the uranographic chart were already determined upon. Fixed stars were designated according to the different groups or constellations which were known by the names they have retained to this day.