Book of Indian Eras, with Tables for Calculating Indian Dates c22.1

c22.1

THIS era dates from the morning after the flight (*Hijra*) of Muhammad from Mekka to Medina, which took place on the night of the 15th July A.D. 622. The year 1, therefore, began on *Friday*, 16th *July* 622. The year is a simple lunar one of 12 lunations or lunar months, of 30 and 29 days alternately. The common year, therefore, consists of only 354 days. But as a month of 29½ days is somewhat less than one mean lunation, an intercalary day is added to the last month in the 2nd, 5th, 7th, 10th, 13th, 16th, 18th, 21st, 24th, 26th, and 29th years of each period of 30 years, so that the year consists of 354 11/30 days, which makes the mean lunation 29 191/360 days, or 29·5305555. This differs from the mean synodical revolution of European astronomers by only ·0000332 of a day. The Muhammadan lunar year of 354 11/30, or 354·3666 days, is, therefore, 0·970202 of the solar year of 365·25 days of the Julian reckoning.