Draft proposals for calendar reform Isaac Newton c. 1,099 words The Newton Project Falmer 2009 Newton Project, University of Sussex

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 1699 and later, c. 1,270 words. 'Regulæ pro determinatione Paschæ' (draft and fair copy) [Yahuda Ms. 24e]Yahuda Ms. 24Draft proposals for rectifying the Julian calendar [Yahuda Ms. 24c] Yahuda Ms. 24d, National Library of Israel, Jerusalem, Israel IsraelJerusalemNational Library of Israel Yahuda Mss Yahuda Ms. 24d SL222

40

 1699 and later England English Latin Holograph

A number of jotted calculations at the beginning of the document have been omitted from the transcription.

 ReligionChronology Catalogue information compiled by Rob Iliffe, Peter Spargo & John Young Tagged transcription by John Young Proofed by Robert Iliffe Catalogue exported to teiHeader by Michael Hawkins
1r Annis 365 14 d. − 11′. 13″. 92 365 14 − 11′. 31″. 2 365 14 − 10′. 56. 64 365 14 − 10′. 48″Ann. Greg
10′. 48″ // 10′. 56″. 64 // 11′. ″ 13′. 92 // 11′. 31″. 2 facit in annis 5000 facit 37 12 , 38, 39, 40 dies respective. Observationes Hipparchi Anno Periodi 3 Calippi Ante Christūum Alexandriæ Temp. appar Grenovici Temp. med Grenovici Locus ☉ ex calculo si annus 36514 dies − 11′ 17 162 Sept 27 sub occas. ☉ 27.d 3.h 44′ 20 159 Sept 27 sub ort ☉ 26. 15. 44 21 158 Sept 27 in ips. merid. 26. 21. 44 232 147 Sept 26 media nocte 26. 9. 44 323 146 Sept 27 mane 26. 15. 44 32 146 Mar 24 mane et iterūum hora diei 5ta 23. 15. 44 & 23. 20. 44 36 143 Sept. 26 vesp. 26. 3. 44 43 135 Mart 23 circa med. noct 23. 9. 44 49 128 Mart 23 sub occas. ☉ 23. 3. 44 162 Sept 267. 1314 26. 22. 59 158 Sept 27. 12 12 26. 22. 14 146 Sept 27. 10 14 26. 2019. 59 159 Sept. 27. 1 34 26. 11. 29 147 Sept. 276. 23 12 26. 9. 14 143 Sept. 26 22 34 26 8. 29 17 162. Sept. 27. 00.44 27. 06. 0 − 5. 16 20 159 Sept. 276. 178.11 26. 18. 0 + 0. 11 21 158 Sept. 27. 00.00 27. 00. 0 + 0. 00 32 147 Sept. 26. 15.59 26. 12. 0 + 3. 59 33 146 Sept. 26. 21.48 26. 18. 0 + 3. 48 36 143 Sept. 26. 15.15 26. 06. 0 + 9. 15 32 146 Mar 23. 20. 1 23. 20. 30. (6) + 12. 29 (2. 5 − 0. 29 43 135 Mar 23. 12. 0 23. 12. 0 − 0. 0 49 128 Mar 23. 4.43 23. 06. 0 − 1. 17 50. 3) − 1. 46 (35 13 − 7.′ 14″ æq. t. Diff merid 2h 15′ Diff merid 2h 15′ Temp appar mediocre cor Alexand Temp appar Grenovici Alexand Temp. appar. Grenovici 27. 8. 5 26. 22. 39 26. 20. 24 26. 20. 5 26. 16. 6 26. 13. 51 27. 2. 5 26. 21. 55 26. 19.40 26. 14. 5 26. 13. 54 26. 11. 39 26. 20. 5 26. 19. 43 26. 17. 28 26. 8. 5 26. 13. 10 26. 9. 55 23. 20. 36 23 18. 21 23. 12. 35 23. 10. 20 23. 5. 18 23. 3. 3 And at yethe end of every 500 years the larger period of lunar months wchwhich shall or should be then running shall contein only 45 m lunar months & consist of the three lesser periods each of wchwhich shall of wchwhich that larger period consists shall each of them contein only 15 lunar months, the two last months of the two periods co conteining 17 months being then omitted. The advantage of this Calendar above yethe Gregorian in respect of the solar y is that in yethe Gregorian the Solar year errs a day in 5000 years in this it errs a day & by that error recedes from yethe state it had in yethe age of Christ, in this it errs a day in 10000 years & by that error approaches the state it had in yethe age of Christ so that in 30000 years it will a the equinox will fall on yethe 24th of March as it did in yethe age of Christ & in 110000 years the beginning of Ianuary will fall on yethe winter solstice as it ought to do. Also yethe recconing by 500, 1000, 1500 &c runs in rounder & fewer numbers then that by 400, 800, 1200, 1600. And tho yethe Kalendars differ yet yethe stiles they will agree in stile for 700 years to come. 1v The advantage in respect of yethe Lunar year is that much greater. For in the Gregorian Kalendar the full Moon on wchwhich Easter depends requires is not to be found wthwith out yethe help of three or four Tables, & when you have that full moon there is no rule in that Kalendar for finding yethe other full moons & yethe new moons throughout yethe year. But in this Kalendar all the new & full Moons are found perpetually without any Tables at all or any other recconing then yethe continuall addition of yethe 230 & 29 days wchwhich is so very easy a work that any Novice may perform it. And besides this rule is exacter then yethe Gregorian for that errs thre hours & t in 239 years this errs but 3 hours in five hundred years. Folio 2r is blank. A series of calculations on f. 2v is here omitted from the transcription. 3r The advantage of this Kalendar above yethe Gregorian in respect of yethe solar year is that yethe solar year in yethe Gregorian errs a day in 5000 years & by that error recedes from yethe state it had in yethe age of Christ, in this it errs a day in 10000 years & by that error approaches the state it had in yethe age of Christ so that in 30000 years the equinox will fall on yethe 24th of March as it did in yethe age of Christ & in 110000 years the beginning of Ianuary will fall on yethe winter solstice as it ought to do. Also the recconing by 500, 1000, 1500 &c runs in rounder & fewer numbers then that by 400, 800, 1200, 1600 &c. And tho yethe Kalendars differ yet they will agree in stile for 700 years to come. The advantage in respect of yethe Lunar year is much greater. For in yethe Gregorian Kalendar yethe full Moon on wchwhich Easter depends is not to be found wthwithout the help of three or four Tables, and when you have that full moon there is no rule in that Kalendar for finding the other full moons & yethe new moons throughout yethe year. But in this Kalendar all yethe new & full moons are found perpetually wthwithout any Tables or any other recconing then yethe continual addition of 30 & 29 days alternately wchwhich is so very easy a work that any Novice may perform it. And besides this rule is much exacter then the Gregorian for that errs three hours in 39 years this errs but 3 hours in 500 years, & may be corrected eveyevery 500 years to keep it exact.