# Epacts sentence example

epacts
• On This Account Lilius Thought Fit To Reject The Golden Numbers From The Calendar, And Supply Their Place By Another Set Of Numbers Called Epacts, The Use Of Which We Shall Now Proceed To Explain.
• In Like Manner The Epacts Of All The Following Years Of The Cycle Are Obtained By Successively Adding Eleven To The Epact Of The Former Year, And Rejecting Thirty As Often As The Sum Exceeds That Number.
• This Method Of Forming The Epacts Might Have Been Continued Indefinitely If The Julian Intercalation Had Been Followed Without Correction, And The Cycle Been Perfectly Exact; But As Neither Of These Suppositions Is True, Two Equations Or Corrections Must Be Applied, One Depending On The Error Of The Julian Year, Which Is Called The Solar Equation; The Other On The Error Of The Lunar Cycle, Which Is Called The Lunar Equation.
• The Solar Equation Occurs Three Times In 400 Years, Namely, In Every Secular Year Which Is Not A Leap Year; For In This Case The Omission Of The Intercalary Day Causes The New Moons To Arrive One Day Later In All The Following Months, So That The Moon'S Age At The End Of The Month Is One Day Less Than It Would Have Been If The Intercalation Had Been Made, And The Epacts Must Accordingly Be All Diminished By Unity.
• Thus The Epacts I 1, 22, 3, 14, &C., Become 10, 21, 2, 13, &C. On The Other Hand, When The Time By Which The New Moons Anticipate The Lunar Cycle Amounts To A Whole Day, Which, As We Have Seen, It Does In 308 Years, The New Moons Will Arrive One Day Earlier, And The Epacts Must Consequently Be Increased By Unity.
• Thus The Epacts 11, 22, 3, 14, &C., In Consequence Of The Lunar Equation, Become 12, 23, 4, 15, &C. In Order To Preserve The Uniformity Of The Calendar, The Epacts Are Changed Only At The Commencement Of A Century; The Correction Of The Error Of The Lunar Cycle Is Therefore Made At The End Of 300 Years.
• In The Gregorian Calendar This Error Is Assumed To Amount To One Day In 3121 Years Or Eight Days In 2500 Years, An Assumption Which Requires The Line Of Epacts To Be Changed Seven Times Successively At The End Of Each Period Of 300 Years, And Once At The End Of 400 Years; And, From The Manner In Which The Epacts Were Disposed At The Reformation, It Was Found Most Correct To Suppose One Of The Periods Of 2500 Years To Terminate With The Year 1800.
• These Are Exhibited In The Subjoined Table (Table Iii.) Called The Extended Table Of Epacts, Which Is Constructed In The Following Manner.
• The Series Of Golden Numbers Is Written In A Line At The Top Of The Table, And Under Each Golden Number Is A Column Of Thirty Epacts, Arranged In The Order Of The Natural Numbers, Beginning At The Bottom And Proceeding To The Top Of The Column.
• The Second Column, Corresponding To The Following Year In The Lunar Cycle, Must Have All Its Epacts Augmented By 11; The Lowest Number, Therefore, In The Column Is 12, Then 13, 14, 15 And So On.
• Each Of The Thirty Lines Of Epacts Is Designated By A Letter Of The Alphabet, Which Serves As Its Index Or Argument.
• In That Year The Omission Of The Intercalary Day Rendered It Necessary To Diminish The Epacts By Unity, Or To Pass To The Line C. In 1800 The Solar Equation Again Occurred, In Consequence Of Which It Was Necessary To Descend One Line To Have The Epacts Diminished By Unity; But In This Year The Lunar Equation Also Occurred, The Anticipation Of The New Moons Having Amounted To A Day; The New Moons Accordingly Happened A Day Earlier, Which Rendered It Necessary To Take The Epacts In The Next Higher Line.
• In This Manner The Line Of Epacts Belonging To Any Given Century Is Easily Found, And The Method Of Proceeding Is Obvious.
• When The Solar Equation Occurs Alone, The Line Of Epacts Is Changed To The Next Lower In The Table; When The Lunar Equation Occurs Alone, The Line Is Changed To The Next Higher; When Both Equations Occur Together, No Change Takes Place.
• In Order That It May Be Perceived At Once To What Centuries The Different Lines Of Epacts Respectively Belong, They Have Been Placed In A Column On The Left Hand Side Of The Table On Next Page.
• The Use Of The Epacts Is To Show The Days Of The New Moons, And Consequently The Moon'S Age On Any Day Of The Year.
• When The Epact Of The Year Is Known, The Days On Which The New Moons Occur Throughout The Whole Year Are Shown By Table Iv., Which Is Called The Gregorian Calendar Of Epacts.
• When 25 And 26 Occur In The Same Line Of Epacts, The 25 Is Not Accented, And In The Calendar Stands Beside 24.
• For Example, If We Observe The Line B In Table Iii., We Shall See That It Contains Both The Epacts Twenty Four And Twenty Five, So That If These Correspond To The Same Day Of The Month, Two New Moons Would Be Indicated As Happening On That Day Within Nineteen Years.
• The new moons indicated by the epacts also differ from the astronomical new moons, and even from the mean new moons, in general by one or two days.