History of Dharmashastra (Ancient and Mediaeval Religious and Civil Law in India) v6.c81.255

v6.c81.255

Tithi is defined as the time or period required by the moon to gain twelve degrees on the sun As the Sūryasiddhānta states 'tithi is the lunar day in which the moon leaving the sun (at the last moment of Amāvāsyā), traverses twelve degrees (*bhāgas*) towards the east every day.'¹⁷¹ The moon's motion is irregular and therefore the moon traverses twelve degrees sometimes in 60 ghaṭikās, sometimes in more (up to about 65) and sometimes in less ghaṭikās up to about 54 The result is that one unit day may be co-terminous with one tithi, but often a unit day has two tithis i e in the morning it may be the 6th tithi, but in the afternoon, evening and night it may be the 7th It is possible that in a single civil day (from sunrise to sunrise) there may be three tithis e g. on Monday morning there may be only two ghaṭikās left of the 6th tithi, then the 7th tithi may be only 56 ghaṭikās in duration and then the 8th may follow for the last two ghaṭikās of that unit day Conversely, a single tithi may touch three days For example, the last two ghaṭikās of Monday may be the first two ghaṭikās of the 6th tithi, then the 60 ghaṭikās of Tuesday may be occupied by the 6th tithi and two more ghaṭikās (the last) of the 6th tithi may spread on to Wednesday morning A unit day which spreads over three tithis is declared by the Rājamārtanda to be very holy¹⁷² (or auspicious), while on the other hand a tithi touching three days is said to be inauspicious for marriage, for marching on an invasion, for an auspicious religious act or an act meant to advance prosperity.¹⁷³ If a tithi begins immediately before sunrise or its beginning coincides with sunrise and ends after the following sunrise the name of the tithi (as pratipad, dvitīyā or so on as the case may be) is coupled with both divasas (civil days) involved, so that two tithis of the same denomination appear one after another This is called vr̥ddhi of the particular tithi. If a tithi begins sometime after sunrise on one morning and ends before sunrise on the following day it cannot be coupled with any day and is therefore deleted or omitted in the pañcāṅga (almanac) and there is *tithi-kṣaya*. As a tithi is normally shorter than the civil day kṣaya occurs more frequently than *vr̥ddhi*.