172 Journal of the Asiatic Society of Bengal. [N.S., XV, 
any tim 
The ‘Hindu system involves the use of two different and 
independent epicycles for each planet (except the sun and 
moon) and four sets of calculations, and the epicycles, at least 
in the later works, vary i n dimensions with reference to their 
positions on the deferent. In the Stirya Siddhanta these epi- 
cycles are termed manda paridhi, or ‘epicycle of the apsis, 
and sighra paridhi, or ‘epicycle of yee asal and their 
dimensions as given in that work are as follows * 
DIMENSIONS Or EPIcycies. 
Circumference of manda | Circumference of sighra 
paridhi = Ey. idhi = Ee. 
Anomaly | Anomaly Anomaly | Anomaly 
0° or 180”. | 90° or 270’. | 0° or 180”. 90° or 270”. 
eel asst eee | eS Federal 
41 ae a 14° 0’ | 13° 40’ 
Moon .. ..{ 32° 0° | 31° 40 
Mars a | ke 235° 0’ 232° 0’ 
MERCURY Boe Ae 28° 0" 133° 0’ 132° 0’ 
JUPITER 33° 0’ 32° 0’ a ow =. 
VENUS igo” 1 262° 0’ | 260° 0” 
SaTURN 49° 0’ 48° 0’ ai | 40° 0’ 
The change in ae dimension of the epicycle is proportional 
to the sine of the anomaly. If aZ is the difference as given 
in the table and 9 the anomaly then the dimension at 6 i 8 given 
y £— aE. sin 4, or, if the Hindu sine function is used, by 
E- aE.sin6/r. This result is based upon the proportion 
Ms sin 6 
AE - sin 90° 
where zx is the diminution at 6. If 
pee 
e. 360° =F — AE sin 6, or E — ~~ sin 0 
we may term ‘e’ the reduced epicyele. 
* Brahmagupta gives: Sun 14° to 13° 40’; Moon 36° 31’ to 30° 44’. 
