The Mayas had a calendar of 360 days, with intercalary days; this solar year was intersected by their sacred year of twenty weeks of thirteen days each, and these assembled in bewildering cycles.
It was thus an effective compromise between the solar year and the lunar month, and contrasts very favorably with the intricate and clumsy years of other ancient systems. The leap-year of the Julian and Gregorian calendars confers the immense benefit of a fixed correspondence to the seasons which the Egyptian year did not possess, but the uniform length of the Egyptian months is enviable even now.
Both festivals, of course, belong to a lunar calendar, and move through the solar year every thirty-two years.
The Lunar Year, Consisting Of Twelve Lunar Months, Contains Only 354 Days; Its Commencement Consequently Anticipates That Of The Solar Year By Eleven Days, And Passes Through The Whole Circle Of The Seasons In About Thirty Four Lunar Years.
This Differed From The Solar Year By Ten Whole Days And A Fraction; But, To Restore The Coincidence, Numa Ordered An Additional Or Intercalary Month To Be Inserted Every Second Year Between The 23Rd And 24Th Of February, Consisting Of Twenty Two And Twenty Three Days Alternately, So That Four Years Contained 1465 Days, And The Mean Length Of The Year Was Consequently 3664 Days.
The civil year commenced with the calends of January, but this did not hold a fixed place in the solar year till the time of Julius Caesar(see Calendar).
But in the course of a few years the accumulated difference between the solar year and twelve lunar months would become considerable, and have the effect of transporting the commencement of the year to a different season.
This Period Exceeds Seventy Six True Solar Years By Fourteen Hours And A Quarter Nearly, But Coincides Exactly With Seventy Six Julian Years; And In The Time Of Calippus The Length Of The Solar Year Was Almost Universally Supposed To Be Exactly 3 6 54 Days.