is a circular masonry disc of 7 alloys, so that it remains of the same size by change of
weather. The hole in the center of the instrument is the position of the Pole Star. The
latitude of Jaipur is 27 degree. The outer circle is graduated in 24 hours of 6
fractions each. The inner circle has 360 degrees, each of 6 sub-divisions. The most
important planets are marked in outer circle at their corresponding position in the sky.
By placing a separate disc in
the hole(which is graduated from 0 degree to 180 degree), of instrument, we can claculate
the positions of various planets and dividing by time interval, the speed of rotation of a
particular planet is calculated and this wat the dates of Sun & Moon eclipses as well
as the Sun-set, Sun-rise, Moon set etc. are calculated.