The True Places of the Poets 71. Sans. and its other uses are closely analogous to those of the more usual term 39. By the corrected epicycle multiply the base-sine (bhajjgd) and perpendicular-xine (oty¢) respectively, and divide by the number of degrees in a circle : then, the arc corre8 ponding to the result from the base-sible (bhajujubphol) is the cquation of the apsis (mtoc patt), in minutes, etc. All the prelirina¥y operationB having been already performe , this is the final process by which is quertained the equation of the psis U the amount by which a planet is, at any point in its revolution, drawn away from its neam place by the disturbing influence of the apsis. In motern phraseology, it is called the first inequality, due to the ellipticity of the rbit; or, the equation of the centre. ignre B, upon he next page, will serve to illustrate the nethod of the process Let AMM£ P represent a part of the orbit of any planet, which is supposed to be a true circle, having CE, the earth, for its centre. Along this orbit the planes would nove, in the direction indicated by the axow, tom A through Mi. and My to P, ७nd so on, with an equable motion. were it not for the attraction of the beings situated पt the apsis (nodoce@) and conjunction (eigroect xaspectively The general mode of action of these beings has been explained above, under verses 1-5 of this chapter we have now +o ascertain the amount of the disturb. ank produced by them at any given point in the planet's revolution . The method devised is that of an epicycle, upon the circumference of which the planet roolies with an equable motion, while the centre of the epicycle traverses the orbit with a welocity equal to that of the planet's mean motion, having always a position coincident with the mean place of the planet. At present, we have to do only with the epicycle which +opresents the disturbing effect of the apsis (axioced). The period of the planet's fevolution about the centre of the epicycle is the time which it bakes the latter to make the circuit of the orbit from the apsis axound to the apsis aggin, or the period of its anomalistic revolution. This is almost precisely equal to bhe period of sidereal Revolution in the case of all the planets excepting the moon, since theih: apsides are re. garded by the Hindus Exe stationary (see above, under i, 41-44): the noon's 3psis, however, has a forward motion of more than 40° in a year; hence the moon's anomalistic revolution 16a very perceptibly longer than its siderenl, being 27d 18 1B The age of the epieycle braversed by the planet at any meap point in its revolution is accord. ingly always equal to the age of the orbit intercepted between that
