Indian Epigraphy c15.s1.t1.7

c15.s1.t1.7

A rule for finding out the Christian equivalent of a given Hijrī year is as follows : Multiply the Hijrī year by 970203, cut off six decimals, add 622.54 and the sum will be the year of the Christian era, and decimal of the day following, in old style. Thus Hijrī 1215 × 970203 = 1178.796645, leaving 1178+622.54=1800.54. Another system is: Multiply the Hijrī year by 2.977 (the difference between 100 solar and as many lunar years); divide the product by 100, and deduct the quotient from the Hijrī year; add to the result 621.569, and the quotient will be the Christian year from the date at which the Muhammadan year begins. Thus Hijrī 1269 × 2.977 = 37778; 37778 ÷ 100 = 37.778; 1269 - 37.778 = 1231.222 + 621.569 = 1852.791 (791 or 9 months 15 days indicating the commencement of Hijrī 1269 on the 15th October). The formula of finding the Hijrī equivalent of a given Christian year is as follows : Subtract 622 from the current year; multiply the result by 1.0307; cut off four decimals, and add 46; the sum will be the year which, when this is a surplus decimal, requires the addition of 1. Thus 1852 - 622 = 1230; 1230 × 1.0307 = 1267.7610 + 46 = 1268.22; add 1 and we have the Hijrī year 1269.³