________________
JANUARY, 1984
Differentiating both sides w.r.t time t, we have
d(RMB) = d
(Radius of Meru's base on flat earth remains constant.)
Thus the rate of variation of radii of the solar mandalas is in toto the same as the rate of variation of their north polar distances (NPD) from periphery of the mount Meru's base on flat earth.
So using Eq. No. (3), we have from Eq. No. (12) that
48
Y/day (day and night)
(RMB)
Mn
61
Using Eq. No. (11), we have
&(DM2)
Mn
C
or
Mn
(13)
i.e. diameters of the solar mandalas vary as 535 yojanas per day (day
61
and night).
=
(NPD of Mn)+0........
= 2
The circumference of any solar mandala has verily been computed in an alike manner as R.C. Gupta1 has shown in his paper 'Circumference of Jambudvipa in Jaina Comography' that circumference of Jambudvipa had been computed from its diameter by using only approximate values of π. They had commonly employed the following formula
CM2
=
= 5
535Y/days
61
√ 10 D2
Jain Education International
95
Mn
= √10 D1
where CM=Circumference of Mn (nth solar mandala).
But they did not use the correct value of the square root of ten but instead, for finding out the square root of a non-square positive number N, the following bionominal approximation was frequently used during the ancient and medieval times;
..(12)
Mn
For Private & Personal Use Only
14 Gupta, R. C. (1974), 'Circumference of Jambudvipa in Jaina Cosmography', IJHS, Vol 10, No. 1, pp. 38-46.
(14)
www.jainelibrary.org
