The Length of the Year in the Original Proposal for the Gregorian Calendar

  title={The Length of the Year in the Original Proposal for the Gregorian Calendar},
  author={Noel M. Swerdlow},
  journal={Journal for the History of Astronomy},
  pages={109 - 118}
  • N. Swerdlow
  • Published 1 May 1986
  • History
  • Journal for the History of Astronomy
In a note! published in this journal in 1974 I considered the origin of the length of the year in the Gregorian Calendar, concentrating in particular on the earliest proposal by Petrus Pitatus in 1560for the year eventually adopted in the reformed calendar, the general principles of which are usually attributed to Aloysius Lilius. At the time I had not seen the proposal of 1577, the Compendium novae rationis restituendi calendarium, that preceded the adoption of the calendar in 1582,and as I… 
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