RISHI, an important term in Hindu astronomy, hich, in its scientific sense, means a line or great circle passing through the poles of the ecliptic, and the beginning of the first solar sidereal sign a.nd first fixed lunar mansion of the respective zcxliacs, and which said circle is supposed to cut some of the stars in the Great Bear, which most com mentators take to be Dhube, or TJrsa! Majoris, and Piscium, although in reality no such circle could be made t,o intersect exactly these three points. This line or circle being thus invariably fixed, and tbe four (fixed and moveable) zodiacs conceived to coincide at a particular epoch, the variation of the moveable ones may easily be reckoned by its means, as if it were an •index. Thus, suppose that the line of the Rishi should have intersected the beginning of the fixed lunar mansion Magha, as was supposed to be the case in the 1910th year of the Caliyug (1192 n.c.), and that at the beginning of the said year the line of the Rishi was found by observation to intersect the middle of the moveable niansion Magha, then it would be said truly that the Rishis had got into 20'N 6° 40' k 2 ) of the moveable Magha, and these 6° 40' would mark the absolute precessional varia tion which had accumulated at that epoch since the time that the fixed and moveable Maghas coin cided. The above explanation of the term Rishi is clearly justified by all the Hindu treatises of any weight which have hitherto fallen into the hands of Europeans ; and here it may not be out of the purpose to observe that when Hipparchus (later than the 135th year n.c.), on comparing his
observations of Spic Virginis (the Harshana of the Indians) -with those that Simocharis had made at Alexandria about a century before, and per ceived by the results that the stars appeared to have advanced (though slowly) from west to east relatively to the equinoctial points, he was far from imagining that Indian astronomers (perhaps several centuries before his time, and in all pro bability by observations of the same star) had already noticed the same variation, on which, in after ages, Sir Isaac Newton resolved and estab lished the great problem of the equinoctial pre cession. The celebrated Indian astronomer Aryabhatta, probably puzzled how to account for the change of the position of the line of the Rishis, which, he admitted, had intersected the middle of the moveable lunar mansion Magha in the year of the Caliyug 1910, and which he pretended to cut (when he wrote) the beginning of Aswini, imagined a curious system on the seven stars of the Great Bear, to which he supposed a proper motion to the eastward, at the rate of 13° 20' (a lunar mansion) in 100 years, which amounted to 159,999 revolutions in a calpa, and which squared his account. But this absurd doctrine has long since been abandoned by- all manner of Indian astronomers, many of whom in existence in 1810 had never heard of it.—Lt.-Cel. J. Warren, Kala Sankalita, pp. 85, 245.