fooner than March 22, nor later than April 25th; because those two Days are the earliest and latest Sundays that can poffibly fall next after the first full Moon on or after the 21st of March. Thefe Numbers fo placed will mark the Day of the Pafchal Limit, 'till the Year 1900, when they will need fome Alteration, as may be feen in The Earl of Macclesfield's Remarks upon the Solar and the Lunar Years, in Philof. Transact. N° 495,

3. The Cycle of the Roman Indiction is a Period of 15 Years, which was used by the ancient Romans, but for what Purpose is not now known. It is however used by the Popes, who date their Acts by the Years of the Indiction.

The Golden Number, Cycle of the Sun, and Indiction are found for any Year by this Canon,

When 1, 9, 3, to the Year have added been, Divide by Nineteen, Twenty-eight, Fifteen: By what remains each Cycle's Year is feen +.

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The Reason of adding thefe Numbers, viz. 1 for the Golden Number, 9 for the Cycle of the Sun, and 3 for the Indiction, to the Date of the Chriftian Era, is because fo many Years of the refpective Cycles were elapfed when the Christian Era began. If then you divide the current Year of Chrift, with the Addition of the refpective Number, by the whole Number of the Cycle,

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These three Cycles, multiplied into one another; that is, 28x19x15, amount to 7980, which is called the Julian Period, after which the three foregoing Cycles will begin again together. This Period had its imaginary Beginning 710 Years before the Creation, and is not yet complete. It is much used in Chronological Tables.

the Quotient fhews how many compleat Cycles have run out, fince the beginning of that in which the Christian Era commenced, and the Remainder, if any; fhews the prefent year of the Cycle; if there be no Remainder it is the laft Year, which compleats the Cycle.

С НА Р.

TH

CHA P. IV.

Of the EPACT.

HE Epact is a Number arifing from the Excess of the Solar Year above the Lunar, of 12 fynodical Months, which Excess is 11 Days; or the Epact of any Year expreffes the Number of Days, from the last new Moon of the old Year, (which was the beginning of the prefent Lunar Year) to the 1ft of January. The first Year of the Cycle of the Moon the Epact is o, because the Lunar Year begins with the Solar. On the fecond, the Lunar Year has begun 11 Days before the Solar Year, therefore the Epact is 11. On the third it has begun twice 11 Days before the Solar Year, therefore the Epact is 22. On the fourth it begins three times II Days fooner than the Solar Year; the Epact would therefore be 33, but 30, being an intire Synodical Month, muft that Year be intercalated; or that Year must be reckoned to confift of 13 Synodical Months, and there remains 3, which is the true Epact of the Year; and fo on to the End of the Cycle, adding 11 to the Epact of the last Year, and always rejecting 30, gives

3

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