23< 



cycle is applied by certain aft'ronomers to all the planets • and by 

 others, is reftricled to few-; and by ibme, is altogether rejected. A'rya- 

 bhat't'a, for example, and the Surya-fidihdnta, make both epicycles 

 of all the planets oval, placing however the fhort axis of the proper 

 epicycles of Jupiter and Saturn in the line of mean coojunaion termed 

 by Hindu aftronomers their quick apogee (Sighrochcha). Brahme- 

 gupta and Bhascara, on the contrary, acknowledge only the epicycles 

 of Mars and Venus to be oval; and infift, that the reft are circular. 

 The author of the Sidd'hdnta Sdrvabkauma goes a Hep further, main* 

 taining that all are circular, and taking the mean between the numberi 

 given in the Surya-fidd'hdnta* 



DIMENSIONS OF THE EPICYCLES, IN DEGREES OF THE DEFERENT. 



© C 3 : - " > ', S % 9 h 



Epicycle of Anomaly. Brahmegupta. 1$ 40 fl" 30' 70 w ±6 40 f 38° 33° IL°&9° |j 30* 



Bhdscara, — > — - — — — — SO 



Circle described on th* 

 great axis of the oval epi- 



..ejie. - Skrja$id£banta,\t 32 7& 30 33- 12 49 



Circle deicribed on the 



less axis,. - . 13.40 31 40 72 28 32 11 . 4& 



Proper epicycle. Brabmsgnptti^ 243 40±6 40+ 132 68 258. |j 40 



&263 

 Circle on the great axis _ 



©fiheoMl epicycle. (Suya Sidd'hanla) 2S * M5 Ti 4& 



Circle on the less axis. c - . - 23S 132, 70 260 3& 



femitranevetfc axis : diff. between tranfverfe and conjugate femiaxis ; ! ordinate of the circle : a fourth 

 proportional; which is precilcly the difference between that ordinate and an ordinate of the eJlipfe forth® 

 fame abfeifs. Hindu aftronomers take it for the difference between the Radius of the circumfcribed circle 

 ard the femidiameter-of the eliipfc at an an jle with the axis equal to the propofed anomaly ; and, ie an 

 ellipfis very little excenuick, the error is fmall. 



+ The epicycles of Man, according to Bsahmig opta and Bka'sc ar a, are increafed infix figns and 

 diminifhed in fix other figsis of anomaly", by a quantity found by this proportion; fine of 45 : fine oc 

 co-fine of anomaly (whichever be the leaft) : : 6° 40': correction additive in fix firft figns, and fab* 

 tractive in fix lad. 



J] The epicyclei of Verms are oval, and the circles defcllhtd on ihz tr&afrerfe and conjugate axis (cir- 

 cle* circumfcribed and.infctibcd) are facte ftated. 



