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 A S T R O N O M Y. 493 account, was the 4714th year of the faid period. There(the number 6f days in a week) there will remain one fore, if to the current year of Chrift we add 4713, the day. If there had been no remainder, it is plain the fum will be the year of the Julian period. So the year year would conftantly begin on the-fame day of the week: but fince one remains, it is plain, that the year muft 1769 will be found to be the 64820! year Of that period. begin and end on the fame day of the week ; and Or, to find the year of the Julian period anfwering to any given year before the firft year of Chrift, fubtradt the therefore the next year will begin on the day follow- number of that given year from 4714, and the remainder ing. Hence, when January begins orr Sunday, A is the dominical or Sunday letter for that year: Then, becaufe will be the year of the Julian period Thus, the year the next year begins on Monday, the Sunday will fall 585 before the firft year of Chrift (which was the 584th on the feventh day, to which is annexed the feventh let-** before his birth) was the 4129th year of the faid period. ter G, which therefore will be the dominical letter for Laftly, to find the cycles of the fun, moon, and indicall that year: and as the third year will begin on Tuef- tion for any given year of this period, divide the given day, the Sunday will fall on the fixth day; therefore F year by 28 19, and 15; the three remainders will be will be the Sunday letter for that year. Whence it is the cycles fought, and the quotients the numbers of cycles evident, that the Sunday lettefs will go annually in a run fince the beginning of the period. So in the above retrograde oijler thus, G, F, E, D, C, B, A. And, ip 4714th year of. the Julian period, the cycle of the fun the courfe of feven years, if they were all common ones, was 10, the cycle ef the moon 2, and the cycle of indicthe fame days of the week and dominical letters would tion 4; the folar cycle having run thrcnigh 168 courfes, return to the fame days of the months. But becaufe there the lunar 248, and the indidtion 314. are 366 days in a leap-year, if this number be divided The vulgar asra of Chrift’s birth vas never fettled till by 7, there will remain two days oyer and above the the year 527, when Dionyfius Exiguus, a Roman abbot, 52 weeks of which the year confifts. And therefore, if fixed it to the end of the 4713th year of the Julian the leap-year begins on Sunday, it will end on Monday; period, which was four years too late. For our Saviour and the next year will begin on Tuefday, the firft Sun- was born before the death of Herod, who fought to kill day whereof mult fall on the fixth of January^ to which him as foon as-he heard of his birth. And, according to is annexed the letter F, and not G, as in common years. -the teftimony of Jofephus (/i. xvii. ch. 8.) there was an By this means, the leap-year returning every fourth eclipfe of the moon in the time of Herod’s laft illnefs ; year, the order of the dominical letters is interrupted; which eclipfe appears by our aftronomical tables to and the feries cannot retnrn to its firlt Hate till after four have been in the year of the Julian period 4710, March times feven, or 2S years; and then the fame days-of 13th, at 3 hours paft midnight, at Jerufalem. Now, the months return in order to the fame days of the week as our Saviour-muft have been born fome months before as before. Herod’s death, fince in the-interval he was carried into From the multiplication of the folar cycle of 28 years Egypt, the lateft time in which we can fix the true asra into the lunar cycle of 19 years, and the Roman indie* of his birth as about the end of the 4709th year of the tion of-15 years, arifes the great Julian period, confift- Julian period. ing of 7980 years, which had its beginning 764 years be- As there are certain fixed points in the heavens from fore Strauchius’s fuppofed year of the creation (for no which aftronomers begin their computations, fo there are later could all the three cycles begin together) and-it is certain points of time from which hiftorians begin to not yet compleated : And therefore it includes all other reckon ; and thefe points or roots of time are called (eras cycles, periods, and asras. There is but one year in or epochs. The moft remarkable seras are, thofe of the the whole period that has the fame numbers for the three Creation, the Greek Olympiads, the building of Rome, cycles of which it is made up: And therefore, if hifto- the sera of Nabonaftar, the death of Alexander, the rians had remarked in their writings the cycles of each birth of Chrift. the Arabian Hegira, and the Perfian Jefyear, there had been no difpute about the time of any degird: All which, together with feveral others of lefs addon recorded by them. note, have their beginnings to the following table fixed The Dionyfian or vulgar asra of Chrifl’s birth was a- to the years of the Julian period, to "the age of the bout the end of the year of the Julian.period 4713 ; and world at thofe times, and to the years before and after confequently the firft year of his age, according to that the year of Chrift’s birth. A Table of remarkable JEras and Events. Julian Ytofthe Before Period World, Chrift. 1. The creation of the world - . . . 4007 706 2. The deluge, or Noah’s flood - - 2362 1656 2351 3. The Aflyrian monarchy founded by Nimrod 1831 2176 2537 4. The birth of Abraham ... 2714 2608 1999 5. The deftruflion of Sodom and Gomorrah 2816 2 i”i o 6. The beginning of the kingdom of Athens by Cecrops 2451 1897 1556 3157 7. Mofes receives the ten commandments from God 3222 2516 ♦ 8. The entrance of the Tfraelites into Canaan 3262 2556 9. The deftnnftion of Troy 3529 2823 Vol. I. No. 21. 23