Page:English translation of the Surya Siddhanta and the Siddhanta Siromani by Sastri, 1861.djvu/21

. The diameter of the Earth is 1600. Multiply the square of the diameter by 10, the square-root of the product will be the circumference of the Earth.

. The Earth's circumference multiplied by the sine of co-latitude (of the given place) and divided by the radius is the or rectified circumference (i. e. the parallel of latitude), at that place.

Multiply the daily motion (in minutes) by the distance of the given place from the Middle Line of the Earth, and divide the product by the rectified circumference of the Earth.

. Subtract the quotient in minutes from the place of the planet (which is found at the mid-night of, as mentioned in 53,) if the given place be east of the Middle Line, but if it be west, add the quotient to it, and (you will get) the planet's place at (the mid-night of) the given place.

. (The cities named) , , &c. are at the line between and the north pole of the Earth, (this line is called the Middle Line of the Earth.)

, and. At the given place if the Moon's total darkness (in her eclipse) begins or ends after the instant when it begins or ends at the Middle Line of the Earth, then the given place is east of the Middle Line, (but if it begins or ends) before the instant (when it begins or ends at the Middle Line, then) the given place is west of the Middle Line.

Find the difference in between the times (of the beginnings or ends of the Moon's total darkness at the given place and the mid-night, which difference is called the .)