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EPIGRAPHIA INDICA.
Place of the Moon. 37. Moon's Nakshatra and Rási.-Dates are frequently coupled with the name of the Nakshatra or asterism in which the moon was at the time of the date; occasionally the rabi or zodiacal sign also is mentioned. Table IX shows which part of the Hindu ecliptic is attributed to each Nakshatra, and Table V that of the single zodiacal signs, e. g. Table IX shows that the Nakshatra Vibakbå denotes 2009-2130 20 of sidereal longitude," and Table V that the sign Kumbha extends from 300° to 330° sidereal longitude. If we know the longitude of the moon, we can tell at once in which Nakshatra and zodiacal sign she stood. It will, therefore, be necessary to calculate the moon's longitude. Now the longitude of the moon=longitude of the sun + distance of sun and moon. The latter element is furnished by the tithi; for, as one tithi is equal to the time required by sun and moon to increase their distance by 120, we need only multiply the tithi for a given moment by 12, to find the distance of the sun and moon in degrees. We found above that, at the beginning of the 28th MArgabira 4319 K.Y. the true tithi was 4-86; it follows that the distance of sun and moon is 12x4.86=520-32 or 52° 19.
The true longitude of the sun for the beginning of every day of the solar year is furnished by the column headed o's longitude in Table VIII, but a correction must be applied for the interval between the beginning of the mean solar year and the beginning of the given day.
Rule.-Having found Cor.' for the year under consideration, add as many minutes to the longitude of the sun as Cor.' contains ghatikás, if .Cor.' is negative; if positive, subtract the amount from the sun's longitude.
Thus for the 28th Margasira 4819 K.Y. we must subtract 14', for Cor.' (+19 gh. 3Bp.- gh. 6p.)=+14 gh. 29p. from the longitude of the sun given in Table VIII for the day under consideration, vis. 237° 49'. The result, 287° 38', is the sun's longitude at the beginning of 28th Margasira 4319 K. Y.
To the longitude of the sun must be added the distance of sun and moon; the result, retrenching 360° if necessary, will be the true longitude of the moon. Turning with the longitude of the moon to Table IX, we find in which Nakshatra the moon was at the moment calculated. In the same way Table V shows through which zodiacal sign she was then passing through. In this example we have
Longitude of the sun . . . . . . . 287° 35' + Distance of sun and moon
. . . . 62° 19' Longitude of the moon , . . . . . . 289° 54' According to Table IX the moon stood in Sravana (280°—299* 20'), and would pass into the next Nakshatra in between 15 and 16 ghatikás, the difference 298* 20—289° 63'=8° 27'. being equal to 15gh. 43p. (the motion of the moon being supposed to be of mean amount), see Table XI. Table V shows the moon to have been in Makara, the Hindu Capricornus.
Yogas. 38. A Yoga is the period, of variable length, in which the joint motion in longitude of the sun and the moon amounts to 13° 20, being the extent of a lunar mansion. There
* The Hindus use sidereal, not tropical, longitude.
