The Ancient year of the Latines was also Luni-solar; for Plutarch [57] tells us, that the year of Numa consisted of twelve Lunar months, with intercalary months to make up what the twelve Lunar months wanted of the Solar year. The Ancient year of the Egyptians was also Luni-solar, and continued to be so 'till the days of Hyperion, or Osiris, a King of Egypt, the father of Helius and Selene, or Orus and Bubaste: For the Israelites brought this year out of Egypt; and Diodorus tells [58] us that Ouranus the father of Hyperion used this year, and [59] that in the Temple of Osiris the Priests appointed thereunto filled 360 Milk Bowls every day: I think he means one Bowl every day, in all 360, to count the number of days in the Calendar year, and thereby to find out the difference between this and the true Solar year: for the year of 360 days was the year, to the end of which they added five days.
That the Israelites used the Luni-solar year is beyond question. Their months began with their new Moons. Their first month was called Abib, from the earing of Corn in that month. Their Passover was kept upon the fourteenth day of the first month, the Moon being then in the full: and if the Corn was not then ripe enough for offering the first Fruits, the Festival was put off, by adding an intercalary month to the end of the year; and the harvest was got in before the Pentecost, and the other Fruits gathered before the Feast of the seventh month.
Simplicius in his commentary [60] on the first of Aristotle's Physical Acroasis, tells us, that some begin the year upon the Summer Solstice, as the People of Attica; or upon the Autumnal Equinox, as the People of Asia; or in Winter, as the Romans; or about the Vernal Equinox, as the Arabians and People of Damascus: and the month began, according to some, upon the Full Moon, or upon the New. The years of all these Nations were therefore Luni-solar, and kept to the four Seasons: and the Roman year began at first in Spring, as I seem to gather from the Names of their Months, Quintilis, Sextilis, September, October, November, December: and the beginning was afterwards removed to Winter. The ancient civil year of the Assyrians and Babylonians was also Luni-solar: for this year was also used by the Samaritans, who came from several parts of the Assyrian Empire; and the Jews who came from Babylon called the months of their Luni-solar year after the Names of the months of the Babylonian year: and Berosus [61] tells us that the Babylonians celebrated the Feast Sacæa upon the 16th day of the month Lous, which was a Lunar month of the Macedonians, and kept to one and the same Season of the year: and the Arabians, a Nation who peopled Babylon, use Lunar months to this day. Suidas [62] tells us, that the Sarus of the Chaldeans contains 222 Lunar months, which are eighteen years, consisting each of twelve Lunar months, besides six intercalary months: and when [63] Cyrus cut the River Gindus into 360 Channels, he seems to have alluded unto the number of days in the Calendar year of the Medes and Persians: and the Emperor Julian [64] writes, For when all other People, that I may say it in one word, accommodate their months to the course of the Moon, we alone with the Egyptians measure the days of the year by the course of the Sun.
At length the Egyptians, for the sake of Navigation, applied themselves to observe the Stars; and by their Heliacal Risings and Settings found the true Solar year to be five days longer than the Calendar year, and therefore added five days to the twelve Calendar months; making the Solar year to consist of twelve months and five days. Strabo [65] and [66] Diodorus ascribe this invention to the Egyptians of Thebes. The Theban Priests, saith Strabo, are above others said to be Astronomers and Philosophers. They invented the reckoning of days not by the course of the Moon, but by the course of the Sun. To twelve months each of thirty days they add yearly five days. In memory of this Emendation of the year they dedicated the [67] five additional days to Osiris, Isis, Orus senior, Typhon, and Nephthe the wife of Typhon, feigning that those days were added to the year when these five Princes were born, that is, in the Reign of Ouranus, or Ammon, the father of Sesac: and in [68] the Sepulchre of Amenophis, who Reigned soon after, they placed a Golden Circle of 365 cubits in compass, and divided it into 365 equal parts, to represent all the days in the year, and noted upon each part the Heliacal Risings and Settings of the Stars on that day; which Circle remained there 'till the invasion of Egypt by Cambyses King of Persia. 'Till the Reign of Ouranus, the father of Hyperion, and grandfather of Helius and Selene, the Egyptians used the old Lunisolar year: but in his Reign, that is, in the Reign of Ammon, the father of Osiris or Sesac, and grandfather of Orus and Bubaste, the Thebans began to apply themselves to Navigation and Astronomy, and by the Heliacal Risings and Settings of the Stars determined the length of the Solar year; and to the old Calendar year added five days, and dedicated them to his five children above mentioned, as their birth days: and in the Reign of Amenophis, when by further Observations they had sufficiently determined the time of the Solstices, they might place the beginning of this new year upon the Vernal Equinox. This year being at length propagated into Chaldæa, gave occasion to the year of Nabonassar; for the years of Nabonassar and those of Egypt began on one and the same day, called by them Thoth, and were equal and in all respects the same: and the first year of Nabonassar began on the 26th day of February of the old Roman year, seven hundred forty and seven years before the Vulgar Æra of Christ, and thirty and three days and five hours before the Vernal Equinox, according to the Sun's mean motion; for it is not likely that the Equation of the Sun's motion should be known in the infancy of Astronomy. Now reckoning that the year of 365 days wants five hours and 49 minutes of the Equinoctial year; the beginning of this year will move backwards thirty and three days and five hours in 137 years: and by consequence this year began at first in Egypt upon the Vernal Equinox, according to the Sun's mean motion, 137 years before the Æra of Nabonassar began; that is, in the year of the Julian Period 3830, or 96 years after the death of Solomon: and if it began upon the next day after the Vernal Equinox, it might begin four years earlier; and about that time ended the Reign of Amenophis: for he came not from Susa to the Trojan war, but died afterwards in Egypt. This year was received by the Persian Empire from the Babylonian; and the Greeks also used it in the Æra Philippæa, dated from the Death of Alexander the great; and Julius Cæsar corrected it, by adding a day in every four years, and made it the year of the Romans.
Syncellus tells us, that the five days were added to the old year by the last King of the Shepherds: and the difference in time between the Reign of this King, and that of Ammon, is but small; for the Reign of the Shepherds ended but one Generation, or two, before Ammon began to add those days. But the Shepherds minded not Arts and Sciences.
The first month of the Luni-solar year, by reason of the Intercalary month, began sometimes a week or a fortnight before the Equinox or Solstice, and sometimes as much after it. And this year gave occasion to the first Astronomers, who formed the Asterisms, to place the Equinoxes and Solstices in the middles of the Constellations of Aries, Cancer, Chelæ, and Capricorn. Achilles Tatius [69] tells us, that some antiently placed the Solstice in the beginning of Cancer, others in the eighth degree of Cancer, others about the twelfth degree, and others about the fifteenth degree thereof. This variety of opinions proceeded from the precession of the Equinox, then not known to the Greeks. When the Sphere was first formed, the Solstice was in the fifteenth degree or middle of the Constellation of Cancer: then it came into the twelfth, eighth, fourth, and first degree successively. Eudoxus, who flourished about