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Accompanied by the Paramesvara Commentary - [Chapter on True Motion]

As it is said: "The sine-arc converted to minutes and divided by the divisor gives the degrees of the planet's correction." The Sun and Moon become "true" (accurate) through the Manda-sphuta the first correction or "slow" correction relating to the apsis process alone. This is also the case for Mars and the other planets. Having calculated the first corrected position, one should keep that position and the true divisor sphuta-cheda together in one place.

Now he describes the method for bringing out the velocity of the first correction: "The cosine..." Multiply the previously calculated cosine-sine kotijya by the planet's own mean velocity and divide by the true divisor. The resulting minutes lipta should be applied to the mean velocity by reversing the signs of addition and subtraction. If the cosine is negative, make it an addition; if the cosine is positive, make it a subtraction. That becomes the velocity of the first correction manda-sphuta-gati. For the Sun and Moon, that itself is the true velocity. To understand the mean velocity, one should calculate the mean position of a planet on two consecutive days and find the difference between them. That difference is the mean velocity. || 4 ||

Now, for the sake of calculating the second correction shighra-phala; the "fast" correction relating to the conjunction of Mars and the others, he describes the method for finding their diameters: "Mars, Jupiter..." Multiply the previously calculated first-correction divisors of Mars, Jupiter, and Saturn by the numbers starting with "Yuga" 4 and divide by the numbers starting with "Tithi" 15 to get the diameters. Specifically: multiply the first-correction divisor of Mars by four (Yuga) and divide by fifteen (Tithi). Take the resulting degrees and, if there is a remainder, divide it to get the minutes. These constitute the diameter of Mars. For Jupiter, multiply its own first-correction divisor by three (Agni) and divide by seven (Shaila); the result, including fractions, is the diameter of Jupiter. For Saturn (Manda), multiply its own first-correction divisor by seven (Agra) and divide by six (Ritu); the result, including fractions, is the diameter of Saturn. These are the "mean" diameters, not yet the "true" ones. For Mercury and Venus: the mean diameter of Mercury (Jna) is twenty-one (Murchana). The mean diameter of Venus (Shukra) is eleven (Isha). For these two, the mean diameter is always this way; no variation arises from the first-correction divisor. || 5 ||

He now describes the "truing" of these diameters and the calculation of the second-correction divisors shighra-cheda from them: "These, increased by one-third of the sine-arc..." These diameters become "true" when increased by one-third of the sine-arc of the second correction. These true diameters...